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Prognostic significance of beta-catenin in colorectal cancer with liver metastasis
Abstract
A decreased expression of beta-catenin has been known to be associated with tumour metastasis. The prognostic value of beta-catenin expression in colorectal cancer (CRC) patients with liver metastasis was evaluated.
Seventy patients who underwent curative resection for CRC with liver metastasis were included. Tissue samples from normal colon mucosa, primary CRC and metastatic liver lesions were prepared in tissue microarrays, and were stained by immunohistochemistry with beta-catenin antibody. The beta-catenin expression of primary CRC tissues and metastatic liver tissues was analysed.
A high expression of beta-catenin (score > 6) was observed in 42.0% and 21.9% of primary colorectal tissues and metastatic liver tissues, respectively. The beta-catenin expression in metastatic liver tissues was significantly lower than in primary CRC tissues (P = 0.022). The patients were classified into two groups according to the difference in the beta-catenin expression score between the primary CRC and the liver metastasis. Group A was defined as patients showing a remarkably decreased expression of beta-catenin in their metastatic liver tissue and group B was defined as patients showing a maintained or increased beta-catenin expression in their metastatic liver tissue in comparison with their primary CRC. The overall survival and disease-free survival rates were better in group B than in group A, and this was statistically significant (P = 0.02, P = 0.002).
The decreased expression of beta-catenin in a metastatic liver lesion may be a poor prognostic marker in CRC with liver metastasis and further investigation is necessary.
... ß-catenin and E-cadherin is important for cell-cell adhesion and breakdown of the E-cadherin/ß-catenin complex results in loss of the 'invasion suppressor system.' Thus, decreased expression of ß-catenin has been observed in many tumors (24)(25)(26). In patients with colorectal carcinoma, decreased or absent membrane expression of ß-catenin has been reported to play a key role in tumor progression and metastasis (27,28). The present study also revealed a significant relation of such expression to a worse prognosis. ...
... only 61.0% for those with decreased ß-catenin expression ( Fig. 2A). This result is consistent with the conclusion that primary colorectal carcinoma with a decreased level of membrane ß-catenin expression is associated with a lower overall survival rate (27,28). Nuclear ß-catenin expression is frequently detected in colorectal carcinoma (29)(30)(31), but its significance as a prognostic indicator is still controversial. ...
Interaction of MUC1 with beta-catenin plays a significant role in tumor progression and invasion. However, the clinical significance of coexpression of MUC1 and subcellular beta-catenin expression in colorectal carcinoma remains unclear. The present study evaluated the clinicopathological significance of their combined expression for predicting prognosis. Seventy-seven colorectal carcinomas were subjected to immunohistochemical staining with anti-MUC1 KL-6 mucin and anti-beta-catenin monoclonal antibody. Positive KL-6 mucin expression was correlated with decreased membranous beta-catenin expression (P=0.022), while no correlation was found between positive KL-6 expression and nuclear beta-catenin expression (P=0.142). Preservation of membranous beta-catenin expression was detected in 35 cases (45.5%) and decreased membranous beta-catenin expression was found in 42 cases (54.5%). Negative KL-6 expression was detected in 31 cases (41.3%) and positive expression was seen in 46 cases (59.7%). Combined positive KL-6 expression and decreased membranous beta-catenin expression was found in 30 patients (39.0%), whose survival was significantly worse than that of patients with other expression patterns for these two molecules (53.3 vs. 84.4%, P=0.005). Multivariate analysis showed that this combination was as an independent predictor of survival. We concluded that the combined pattern of positive KL-6 expression and decreased membranous beta-catenin expression by colorectal carcinoma is a useful biomarker for distinguishing a subgroup of patients with a worse prognosis.
... Extensive cell proliferation occurs in the liver after birth, in conjunction with a substantial increase in β-catenin protein and its nuclear translocation [18]. In fact liver metastasis is often supported by abnormal β-catenin expression and localization [19]. β-catenin accumulation within the nucleus or cytoplasm has been found remarkably in more than half of all cancers and is related to increased tumorigenicity [20]. ...
Background:
Angiogenesis, the formation of new blood vessels from pre-existing vasculature is essential in a number of physiological processes such as embryonic development, wound healing as well as pathological conditions like, tumor growth and metastasis. Hyaluronic acid (HA), a high molecular weight polysaccharide, major component of extracellular matrix is known to associate with malignant phenotypes in melanomas and various other carcinomas. Hyaluronic acid binding protein 1 (HABP1) has been previously reported to trigger enhanced cellular proliferation in human liver cancer cells upon its over-expression. In the present study, we have identified the HA mediated cellular behaviour of liver endothelial cells during angiogenesis.
Methods:
Endothelial cells have been isolated from perfused liver of mice. Cell proliferation was studied using microwell plates with tetrazole dye. Cell migration was evaluated by measuring endothelial monolayer wound repair as well as through transwell migration assay. Alterations in proteins and mRNA expression were estimated by immunobloting and quantitative real time PCR using Applied Biosystems. The paraformaldehyde fixed endothelial cells were used for immuno- florescence staining and F-actin detection with conjugated antibodies. The images were captured by using Olympus florescence microscope (IX71).
Results:
We observed that administration of HA enhanced cell proliferation, adhesion, tubular sprout formation as well as migration of liver endothelial cells (ECs). The effect of HA in the rearrangement of the actins confirmed HA -mediated cytoskeleton re-organization and cell migration. Further, we confirmed enhanced expression of angiogenic factors like VEGF-A and VEGFR1 in endothelial cells upon HA treatment. HA supplementation led to elevated expression of HABP1 in murine endothelial cells. It was interesting to note that, although protein levels of β- catenin remained unaltered, but translocation of this protein from membrane to nucleus was observed upon HA treatment, suggesting its role not only in vessel formation but also its involvement in angiogenesis signalling.
Conclusions:
The elucidation of molecular mechanism (s) responsible for HA mediated regulation of endothelial cells and angiogenesis contributes not only to our understanding the mechanism of disease progression but also offer new avenues for therapeutic intervention.
... The study by Han et al. in 2006 validated tissue microarrays analysis for expression of β-catenin on tissue samples from normal colon mucosa, primary CRC and metastatic liver lesions. This study showed that decreased expression of β-catenin in a metastatic liver lesion may be a poor prognostic marker for CRC patients with liver metastasis (14). ...
Background:
Beta catenin plays a key role in cancer tumorigenesis. However, its prognostic significance in patients with colorectal cancer (CRC) remains controversial. It has been demonstrated that 90% of all tumors have a mutation in individual components of multiple oncogenes in Wnt/β-catenin pathway. Accumulation of nuclear β-catenin in cytoplasm leads to uncontrolled cell proliferation. Thus, nuclear β-catenin accumulation may be a valuable biomarker associated with invasion, metastasis and poor prognosis of CRC.
Objectives:
In this study the prognostic value of beta catenin expression in 165 Iranian CRC patients was evaluated.
Patients and methods:
In this cross sectional retrospective study immunohistochemistry analyses of formalin-fixed paraffin-embedded (FFPE) tumor tissues were performed to characterize the expression of nuclear β-catenin in a series of 165 Iranian patients with colorectal carcinoma. Heat-induced antigen retrieval using the microwave method was applied for all staining procedures. Staining was scored independently by two observers, and a high level of concordance (90%) was achieved. Statistical analysis was done using the SPSS software for Windows, version 13.0.0 (SPSS Inc., Chicago, IL). Two-tailed P < 0.05 was considered statistically significant.
Results:
The patients consisted of 85 males and 80 females. Eighty-eight patients had primary tumor of the rectum and sigmoid, while 77 patients had primary tumor of the colon. The mean period of follow-up was 47.2 ± 10 months and the median period of follow-up was 38 months (range 6 - 58) for each patient. Of 165 tumors, 32 tumors (19.39 %) showed expression of β-catenin and 133 (80.6 %) were negative for β-catenin expression. Based on our findings the distribution of Microsatellite Instability (MSI) status differed between patients with nuclear β-catenin positive and negative tumors and this difference was significant (P = 0.001). Patients with nuclear β-catenin positive expression profile were found to be younger than patients with negative nuclear β-catenin expression (P = 0.010). Univariate and multivariate analysis showed that tumors with β-catenin expression had a poorer prognosis compared to tumors without β-catenin expression.
Conclusions:
According to our findings, the distribution of nuclear b-catenin expression is a poor prognostic marker in patients with colon cancer.
... Inactivating APC mutations as well as changes in β-catenin gene (CTNNB1) often occur in colorectal tumors [13][14][15]. Additionally, changes of β-catenin and E-cadherin expression were observed in colorectal carcinoma [16][17][18]. ...
s: AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics--Nov 15-19, 2009; Boston, MA
Introduction: Beta‐catenin is a member of a cadherin‐catenin complex mediating cell adhesion. It is also a key protein of Wnt/Beta‐catenin pathway responsible for cell cycle and proliferation. This is important for initiation and progression of colorectal cancer. The aim of this study was to determine expression and localization of E‐cadherin, Beta‐catenin and Wnt‐1 proteins in colorectal tumors.
Description: Forty‐four unrelated patients with advanced colorectal carcinoma (CRC) were enrolled consecutively from CRC patients attending palliative care. Expression of Beta‐catenin, E‐cadherin and Wnt‐1 was determined by immunohistochemistry on formalin‐fixed, paraffin‐embedded primary colorectal tissue. The expression was scored by two independent observers who had no knowledge of the clinical data. Correlation was measured with Spearman test, overall survival were analyzed with Kaplan‐Meier method. Log‐rank test was used for univariate analysis, while Cox regression model for multivariate analysis. A value of p < 0,05 was considered significant.
Results: Decreased expression of membrane E‐cadherin and Beta‐catenin was observed in 34% and 27% of patients, respectively. Abnormal cytoplasmic E‐cadherin was detected in 32% of cases and abnormal cytoplasmic and nuclear Beta‐catenin was detected in 50% and 25% of patients, respectively. 60% of patients had decreased cytoplasmic Wnt‐1 expression. Correlation was seen between cytoplasmic E‐cadherin and cytoplasmic Beta‐catenin (R 0,35; p=0,019). Nuclear localization of Betacatenin was correlated with localization of primary tumor (the highest expression in rectum) (R 0,48; p=0,001) and tumor size (R 0,32; p=0,035). Lower Wnt‐1 expression was correlated with higher nodal stage (R ‐0,31; p=0,047). Nuclear Beta‐catenin was an adverse prognostic factor in univariate analysis (log‐rank test p=0,034) which was confirmed in multivariate analysis (HR 4,27 95% CI 1,70–10,72; p=0,002). Higher CEA serum level before treatment (HR 4,30 95% CI 1,35–13,66; p=0,013) and female sex (HR 2,75 95% CI 1,24–6,10; p=0,013) were also independent prognostic factors.
Conclusions: This finding supports that Beta‐catenin is an independent prognostic factor for colorectal carcinoma.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B33.
... Inactivating APC mutations as well as changes in β-catenin gene (CTNNB1) often occur in colorectal tumors131415. Additionally, changes of β-catenin and E-cadherin expression were observed in colorectal carcinoma161718. The aim of this study was to determine the expression and localization of β-catenin, E-cadherin and Wnt-1 in colorectal tumors and to assess the impact of expression of studied proteins on patients survival. ...
Wnt/β-catenin pathway plays an important role in initiation and progression of colorectal oncogenesis. The aim of this study was to determine expression and localization of E-cadherin, β-catenin and Wnt-1 proteins in colorectal tumors. Expression of β-catenin, E-cadherin and Wnt-1 was determined by immunohistochemistry on advanced colorectal cancers. Abnormal expression of E-cadherin, β-catenin, Wnt-1 was observed. Additionally, we revealed correlations between levels of studied proteins and histoclinical data. In multivariate analysis nuclear β-catenin, higher carcinoembryonic antigen serum level before treatment, female sex and tumor localized in colon or rectum were independent unfavorable prognostic factors. These findings support the hypothesis that Wnt/β-catenin pathway plays an important role in advanced colorectal carcinoma.
... With reg ard to the relationship between the E-cadherin/catenin complex expression and patients' sur vival in HCC, we found that patients with low expression of these five molecules had poorer prognosis than those with normal expression. Unlike most previous reports38394041 , which revealed only one or a few members of this complex were associated with patients' survival, our result demonstrated that all molecules of E-cadherin/catenin complex were significantly correlated with HCC patients' survival. However, when E-cadherin/catenin complex status and other clinicopathological parameters were analyzed by the Cox regression model, abnormal expression of the E-cadherin/catenin complex was not found to be an independent prognostic factor. ...
To examine the immunoreactivity of E-cadherin and four subtypes of catenin family in human hepatocellular carcinomas (HCCs) and to investigate the correlation between expression of E-cadherin/catenin complex and clinicopathologic parameters of HCC patients.
An immunohistochemical study for E-cadherin and catenins was performed on 97 formalin-fixed, paraffin-embedded specimens of HCC.
Reduced expression of E-cadherin, alpha-, beta-, gamma-catenin and p120 was observed in 69%, 76%, 63%, 71% and 73%, respectively. Both expressions of E-cadherin and catenin components were significantly correlated with tumor grade (P = 0.000). It showed significant difference between expression of catenin members and tumor stage (P = 0.003, P = 0.017, P = 0.007 and P = 0.000, respectively). The reduced expression of E-cadherin in HCCs was significantly correlated with intrahepatic metastasis (IM) and capsular invasion (P = 0.008, P = 0.03, respectively). A close correlation was also observed between the expression of catenins and the tumor size (P = 0.002, P = 0.034, P = 0.016 and P = 0.000, respectively). In addition, the expression of each catenin was found correlated with IM (P = 0.012, P = 0.049, P = 0.026 and P = 0.014, respectively). No statistically significant difference was observed between the expression level of E-cadherin/catenin complex and lymph node permission, vascular invasion and satellite nodules. Interestingly, only expression of p120 showed correlation with AFP value (P = 0.035). The expression of E-cadherin was consistent with alpha-, beta-, gamma-catenin and p120 expression (P = 0.000). Finally, the abnormal expression of E-cadherin/catenin complex was significantly associated with patients' survival (P = 0.0253, P = 0.0052, P = 0.003, P = 0.0105 and P = 0.0016, respectively). Nevertheless, no component of E-cadherin/catenin complex was the independent prognostic factor of HCC patients.
Down-regulated expressions of E-cadherin, catenins and p120 occur frequently in HCCs and contribute to the progression and development of tumor. It may be more exact and valuable to detect the co-expression of E-cadherin/catenin complex than to explore one of them in predicting tumor invasion, metastasis and patient's survival.
The samples of colon adenocarcinomas (CAC) and their lymph node metastases from 22 patients were studied. The expression of thymidylate synthase (TS), vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), E-cadherin, beta-catenin, tenascin C (TN), and KAI-1/CD82 in primary CAC and their lymph node metastases was compared using an immunohistochemical method. The expression of TS, VEGF, EGFR, E-cadherin, TNC, and KAI-1 was statistically significant different in primary CAC and involved lymph nodes. Comparison of the expression of the markers in the pairs of primary CAC and metastasis revealed equal values for TNC and EFGR in 45.5 and 41% of cases, respectively; the number of coincidences in the expression of the other markers was insignificant. Determination of the expression of molecular biological markers in primary CAC and their lymph nodes may serve as a predictor of therapy response and have a prognostic value.
Purpose
The clinical availability of 2-deoxy-2-[18F] fluoro-D-glucose (FDG) dual-time point positron emission tomography/computerized tomography (DTPP) has been investigated in diverse oncologic fields. The aim of this preliminary study was to evaluate the relationship between various immunohistopathologic markers reflecting disease progression of colorectal cancer and parameters extracted from FDG DTPP in colorectal cancer patients.
Materials and Methods
Forty-seven patients with histologically confirmed colorectal cancer were analyzed in this preliminary study. FDG DTPP consisted of an early scan 1 h after FDG injection and a delayed scan 1.5 h after the early scan. Based on an analysis of FDG DTPP, we estimated the maximum standardized uptake value (SUV) of tumors on the early and delayed scans (SUVearly and SUVdelayed, respectively). The retention index (RI) was calculated as follows: (SUVdelayed - SUVearly) × 100/ SUVearly. The clinicopathological findings (size and T and N stages) and immunohistochemical factors [glucose transporter 1 (GLUT-1), hexokinase 2 (HK-2), p53, P504S, and β-catenin] were analyzed by visual analysis.
Results
The RIs calculated from the SUVs ranged from -1.8 to 73.4 (31.8 ± 15.5). The RIs were significantly higher in patients with high T stages (T3 and T4) than with low T stages (T1 and T2; p < 0.05). Among the immunohistochemical analytic markers, GLUT-1 had the highest positive staining rate (93.6%) compared to other markers. Based on univariable analysis, it was shown that the RI of high-level GLUT-1 expression was significantly higher than low-level GLUT-1 expression (p = 0.01), and the RI of high-level p53 expression was slightly higher than low-level p53 expression (p = 0.08). Multivariate analysis to investigate a link between RI and clinicopathologic parameters of colorectal carcinoma showed that GLUT-1, p53, and T staging were independently connected with increased RIs (p < 0.05, total) using backward selection methods. There was no significant statistical relationship between SUVearly and SUVdelayed and clinicopathologic parameters in this study.
Conclusion
The RIs obtained from preoperative colorectal cancers had a significant relationship to tumor size, T staging, GLUT-1, and p53, in contrast to SUVearly or SUVdelayed. Compared with previous reports, our results showed that RI can better predict GLUT-1 expression than HK-2 and other immunohistochemical markers. This study demonstrated that the RI might have the potential to be applied as a prognostic marker in preoperative colorectal cancer.
Objective
The aim of our study was to investigate if common toxicities are correlated to objective response rate (ORR) in metastatic colorectal cancer (mCRC) patients treated by irinotecan based regimens.
Methods
Univariate and multivariate logistic regression analyses were performed to evaluate correlations between common toxicities and binary ORR in 106 mCRC patients from a prospective cohort treated with irinotecan based regimens.
Results
The most frequent severe toxicities (Grade 3/4) were as follows: neutropenia (27.4%), diarrhea (16.9%), leucopenia (12.6%), vomiting (3.2%) and thrombocytopenia (2.1%). Thrombocytosis was observed in 25 (26.3%) patients. ORR was 25.3%. Thrombocytopenia (P = 0.014), line of chemotherapy (P = 0.028) and thrombocytosis (P = 0.033) were correlated with ORR in univariate analysis. In multivariate analysis, thrombocytopenia (odds ratio [OR] = 8.600, 95% confidence interval [CI] = 1.705–43.385, P = 0.009) and first line chemotherapy (OR = 5.155, 95% CI = 1.153–23.256, P = 0.032) positively related to ORR.
Conclusion
Thrombocytopenia may be an indicator of ORR in mCRC patients treated by irinotecan plus 5-fluorouracil/capecitabine. Evidence is not strong enough to prove that irinotecan based regimens-induced diarrhea, leucopenia, neutropenia or vomiting is associated with ORR.
An overview of colorectal cancer discussed (Philip Paty) the good outcome after primary management with local control in 90-95 % of colon and 85 % in rectal cancer patients with major progression to metastases and to death related to hematogenous dissemination. The major disease pathways include the APC, aneuploid pathway involving mutations of P53, KRAS, SMAD 4, or the CMP/MSI pathway, mismatched repair defect as characterized by Lynch syndrome, the major hereditary form which may also have KRAS and P53 mutations. The common sporadic colorectal cancers are MS1 high, with many patients having BRAF and KRAS mutations. The sentinel node biopsy in colorectal cancer surgery may provide more definitive staging and perhaps modification of the extent of resection with better outcome as suggested by Dr. Saha. The identification of sentinel lymph nodes outside of the planned bowel resection may increase the resection biologically indicated by the sentinel lymph node location leading to better outcome. In a small study by Dr. Saha, the operation was enhanced in 21 % by extending the length of bowel resection, which increased node recovery to 18.5 nodes versus 12 nodes with the more conventional resection, increasing nodal recovery, and positivity to 60 % with reduction to five year recurrence rate to 9 % versus 27 % with the conventional resection. A new (Swiss) technique for pathologic node examination, the OSNA (the One Step Nucleic Acid diagnostic system), was presented which demonstrated increased detection of micro-metastases in a focused pathology study of 22 patients (Zuber) to 11 out of 15 patients versus the 7 micro-metastases identified by the standard single slide per node, and compared to 14 out of 15 with an intensive multi-slide technique. This suggests value in pursuing OSNA study by other centers with relevant clinical trials to establish its true value. An analysis of liver resection for metastatic colorectal cancer (CRC) emphasized the value of 10-year follow-up (DeAngelica). The 10-year survival of 102 patients among 612 patients was 17 % (Memorial Sloan Kettering data). At the five-year point 99 of 102 survivors were NED and 86 have been free of disease since the resection. The usual five-year figure after hepatic resection reveals that one-third of five-year survivors die from recurrence of distant disease suggesting the value of longer term follow-up in these patients. An additional question reviewed related to the role of neoadjuvant systemic chemotherapy (with response rates in the 50 % range) to produce down staging of the hepatic metastases and allow one to retrieve these patients with possible residual disease. In a series of 116 patients who had hepatic resection of CRC metastases in presence of regional node metastases, post neoadjuvant chemotherapy (normally not candidates for resection) these patients were demonstrated to have a 95 % recurrence at median time of 9 months. This raises a cautionary note to the literature report of five-year survivals in the 20-30 % range for hepatic metastases in presence of extra hepatic disease. Such may reflect patient selection rather than a true measure of the biology of disease, and warrant clinical trial evaluation. Lastly, regional therapy and overall systemic therapy were addressed by Dr. Kemeny. The CALGB study of hepatic artery infusion (HAI) with FUDR, dexamethasone versus 5FU leucovorin showed an overall survival of 24.4 months with HAI versus 20 months with systemic therapy (P = 0.0034). An adjuvant trial of HAI at MSK in 156 patients showed an overall survival benefit at 2 year and recent long term 10yr follow-up showing a significant overall survival of 41 % with HAI versus 27 % with systemic therapy (5FU leucovorin). In the neoadjuvant Nordlinger trial for hepatic metastases, there was a significant outcome differences-the preoperative therapy group had 9.2 % increase of progression free survival versus the surgery alone group which suggests the value of combining neoadjuvant surgery in good risk liver resection candidates. Conclude the final lesson from this well presented mini symposium confirms the need for continued evaluation of the numerous discussion points by clinical trial.
Cell adhesion molecules (CAMs) play a significant role in the metastatic potential of colorectal cancer and thus mediate the prognosis of this common malignancy. The downregulation of cadherins and catenins facilitates tumour cell detachment from the primary site, while the expression of selectins, integrins and members of the immunoglobulin superfamily may support neoplastic progression, intravasation and malignant cell attachment to foreign tissue, leading to the development of metastases. The liver is the main host organ of colorectal metastatic lesions. The process of hepatic invasion originates in the sinusoids, where non-parenchymal cells interact with metastasising ones, through the expression of numerous CAMs, following complex molecular pathways. Concurrently, the selective expression of cell adhesion molecules on different organs and endothelia, in conjunction with the presence of dissimilar adhesion ligands on various colorectal cancer cell lines, suggest that CAMs may also mediate the selection of the host organ, for the development of distant colorectal metastases.
Aldehyde dehydrogenase-1 (ALDH1) is involved in the regulation of cell proliferation and differentiation. Moreover, it is a marker for cancer stem cells (CSC). As CSCs were shown to be the driving force of tumor progression and metastases we suspected that the expression of ALDH1 correlated with the prognostic 5 year survival of colorectal cancer.
ALDH1 expression was analyzed in a highly stratified collective of 186 T3 N0 M0 G2 primary colorectal cancer specimens applying immunohistochemistry. For the analysis a scoring system for the expression of ALDH1 was developed that was aided by the pattern of the subcellular expression of beta-catenin which is a well known indicator for colorectal CSCs.
First, ALDH1 expression could be assigned to two groups which correlated with the absence or presence of nuclear beta-catenin expression. Second, ALDH1 group 2 expression patterning correlated highly significantly with low long term survival (p=0.010) of patients with T3 N0 M0 G2 colorectal cancer. This correlation was found univariately and when applying the multivariate Cox-model.
ALDH1 expression pattern is an independent prognostic marker for survival of T3 N0 M0 G2 colorectal cancer patients.
β-catenin and E cadherin are both membrane-associated proteins which are essential regulators and providers of cellular adhesion. In the metastatic cascade of malignant tumours, detachment of tumour cells from each other is a very important step. It has been shown in several tumour types, that reduced expression of these proteins is important. The aim of our study was to clarify the expression profile of these proteins, and correlate the findings with the metastasizing potential of early stage colon and rectal cancers. Formalin fixed and paraffin embedded samples from 79 Dukes B2 stage colorectal cancer were examined using a tissue microarray approach. The expression of β-catenin and E-cadherin proteins was determined immunohistochemically. Our findings indicated that there is a tendency for metastatic spread in cases when membranous expression of β-catenin is lost (p = 0.062). Similarly metastases in negative cases developed more rapidly, than in positive ones (p = 0.05). Survival rate was worse in the negative cases. The risk of metastasis in rectal cancer was significantly higher in the β-catenin membranously negative than positive groups (p = 0.024) and in case of β-catenin nuclear expression the risk was also higher (p = 0.047). Reduced E-cadherin expression also correlated with development of metastatic disease, but this association was statistically not significant. The immunohistochemical analysis of 79 cases shows that in Dukes B2 stage colorectal tumours clarification of β-catenin and E-cadherin expression patterns is reliable for predicting the metastatic potential of early stage rectal cancer and hence the method may have relevant implications in the therapeutic management of these cancers.
Colorectal cancer is the second leading cause of cancer related death in the United States. The majority of these deaths are due to metastasis, with the liver easily accounting as the most common site of deposit. While there are multiple steps in the CRC hepatic metastatic cascade, this review attempts to summarize the different processes involved, focusing on the most recent discoveries, as well as the associated effects in relation to prognosis. J. Surg. Oncol. 2010; 102: 898-908. (C) 2010 Wiley-Liss, Inc.
Metastasis is recently the most fearsome of cancer. Pancreatic cancer is the fourth leading cause of cancer death. Morbidity and mortality from pancreatic cancer is conspicuously associated with metastasis. However, the mechanism of metastasis is not well described. Early studies mostly focus on the "soil and seed" hypothesis. Recently, the chemotaxis hypothesis has been paid more attention. Cancer cell with high expression of chemokine receptor will spread to the specific sites where the ligand is highly secreted. It has been demonstrated that SDF-1/CXCR4 signaling, one of the most important chemokine receptor-ligand complexes, was considered to play a critical role in pancreatic cancer organ-specific metastasis through some possible pathways. However, studies do not clarify the mechanism of SDF-1/CXCR4 signaling on pancreatic cancer progression. Beta-catenin, an important factor in canonical Wnt signaling pathway, also makes great contributions on cancer invasion and metastasis. It seems that Wnt/beta-catenin has a significant role in pancreatic cancer progression through interactions with different protein complexes. In the previous study of neural development, the relationship between SDF-1/CXCR4 signaling and beta-catenin has been described. It gave a clue to describe the correlation between SDF-1/CXCR4 signaling and Wnt/beta-catenin pathway. According to this, we postulate that beta-catenin is a promising key factor of SDF-1/CXCR4 signaling to regulate the metastasis of pancreatic cancer. With the stimulation of SDF-1 on highly metastatic pancreatic cancer cells, beta-catenin will separate from different complexes, translocate into the nucleus, trigger the expression of target genes and finally promote the migration of pancreatic cancer cells to specific sites. Through the observation of this crosstalk, it is possible to understand more clearly about the pancreatic cancer specific metastasis and to make some contributions on gene therapy of pancreatic cancer.
The azoxymethane (AOM) model recapitulates many features of human colon cancer, lacking an inflammatory component. Dextran sulfate sodium (DSS) induces colitis and promotes AOM-induced colon cancer in mice. Vitamin D analogues are anti-inflammatory and chemopreventive in models of colon cancer. Our aim was to evaluate the anti-inflammatory and chemopreventive efficacy of the vitamin D analogue Ro26-2198 in the AOM/DSS model and in vitro in HCA-7 colon cancer cells.
A/J mice received Ro26-2198 (0.01 microg/kg body wt/day x 28 days) or vehicle by mini-osmotic pump. Animals were treated with a single dose of AOM (5 mg/kg body wt) or vehicle 1 week after pump insertion. Mice received 3% DSS or water x 7 days beginning week 3. Animals were sacrificed after 8 weeks and colon segments were fixed in formalin or flash-frozen. Hematoxylin and eosin colonic sections were examined for dysplasia and colonic lysates were assessed for c-Myc, cyclooxygenase 2, and phospho-(active) extracellular signal regulated kinase (ERK) by Western blotting. For in vitro studies, HCA-7 cells were treated with Ro26-2198 followed by interleukin-1beta (IL-1beta). Proliferation was measured by WST-1 assay.
Ro26-2198 delayed the onset of clinical colitis. Several dysplastic foci were present in the AOM/DSS group; none were found in the Ro26-2198 group. Compared with control, AOM/DSS significantly increased c-Myc (15-fold), cyclooxygenase 2 (COX-2) (2.5-fold), and pERK (10-fold), and Ro26-2198 abolished these increases. In vitro, Ro26-2198 inhibited IL-1beta-induced ERK activation and COX-2 induction and decreased HCA-7 cell proliferation.
Ro26-2198 inhibited proliferative (ERK, c-Myc) and pro-inflammatory (COX-2) signals and progression to dysplasia, suggesting chemopreventive efficacy in this model of colitis-associated carcinogenesis.
Although beta-catenin cytoplasmic stabilization and nuclear translocation play a key role in initiation of colorectal cancer (CRC), the mechanisms are far from clear. The aim of this study was to investigate the relation of expressions of cyclooxygenase (COX)-2 and E-cadherin, and the beta-catenin gene exon 3 mutation to the altered distribution of beta-catenin, and their roles in CRC progression and prognosis.
Expressions of beta-catenin, COX-2 and E-cadherin in 96 tissue specimens were detected by immunohistochemistry, and mutation of beta-catenin gene exon 3 was screened by polymerase chain reaction (PCR) and denaturing high-performance liquid chromatography (DHPLC).
Cytoplasmic/nuclear expression of beta-catenin and reduced membranous expression of E-cadherin were associated, respectively, with the earlier and later stages of sequential colorectal carcinogenesis (p<0.05). The altered distribution of beta-catenin was significantly associated with both high Dukes' stages and poor differentiation of CRC (p<0.05). It also had a parallel relationship with COX-2 overexpression (p<0.05, Spearman's rank analysis), but not with reduced E-cadherin expression. Kaplan-Meier analysis showed a significantly worse survival rate for CRC patients with altered expression of beta-catenin (p<0.05, log-rank test). Nevertheless, we failed to find any exon 3 mutation of beta-catenin gene in all 60 cases of CRC.
Altered distribution of beta-catenin occurs in the early stage of colorectal carcinogenesis and has a parallel relationship with COX-2 overexpression. It may serve as a potential marker for the progression and prognosis of CRC. The exon 3 mutation did not appear contributive to the abnormal expression of beta-catenin in CRCs in a Chinese population.
Cadherins form complexes with groups of cytoplasmic proteins, such as α-, β-, and γ-catenins, that link the cadherin molecule to the cytoskeleton. In this study, we conducted an immunohistochemical investigation of E-cadherin and α-catenin expression in 100 tissue samples obtained from colorectal cancer patients undergoing surgical treatment. Reduced expression of α-catenin was observed in 56 (56%) of the cases and found to be significantly correlated with the depth of invasion of the patients’ colorectal cancer and its metastasis to lymph nodes and liver. In contrast, E-cadherin expression was reduced in 29 (29%) of the cases and was not significantly correlated with either depth of invasion or metastasis. Although the levels of expression of these proteins were positively correlated, coexpression pattern analysis showed that invasion and metastasis were correlated with a reduction of α-catenin expression regardless of the status of E-cadherin staining. Thus, to predict tumor invasion and metastasis in colorectal adenocarcinoma, it is useful to investigate not just the expression of E-cadherin but also the expression of α-catenin.
Axin antagonizes the developmental effects of Wnt in vertebrates. We show here that Axin simultaneously binds two components of the Wnt pathway, beta-catenin and its negative regulator glycogen synthase kinase-3beta. In mammalian cells, Axin inhibits Wnt-1 stimulation of beta-catenin/lymphoid enhancer factor 1-dependent transcription. Axin also blocks beta-catenin-mediated transcription in colon cancer cells that have a mutation in the adenomatous polyposis coli gene. These findings suggest that Axin, by forming a complex with beta-catenin and glycogen synthase kinase-3beta, can block signaling stimulated by Wnt or by adenomatous polyposis coli mutations.
β-Catenin plays a dual role in the cell: one in linking the cytoplasmic side of cadherin-mediated cell–cell contacts to the actin cytoskeleton and an additional role in signaling that involves transactivation in complex with transcription factors of the lymphoid enhancing factor (LEF-1) family. Elevated β-catenin levels in colorectal cancer caused by mutations in β-catenin or by the adenomatous polyposis coli molecule, which regulates β-catenin degradation, result in the binding of β-catenin to LEF-1 and increased transcriptional activation of mostly unknown target genes. Here, we show that the cyclin D1 gene is a direct target for transactivation by the β-catenin/LEF-1 pathway through a LEF-1 binding site in the cyclin D1 promoter. Inhibitors of β-catenin activation, wild-type adenomatous polyposis coli, axin, and the cytoplasmic tail of cadherin suppressed cyclin D1 promoter activity in colon cancer cells. Cyclin D1 protein levels were induced by β-catenin overexpression and reduced in cells overexpressing the cadherin cytoplasmic domain. Increased β-catenin levels may thus promote neoplastic conversion by triggering cyclin D1 gene expression and, consequently, uncontrolled progression into the cell cycle.
The Ca(2+)-dependent cell adhesion molecule uvomorulin is a member of the cadherin gene family. Its cytoplasmic region complexes with structurally defined proteins termed alpha-, beta-, and gamma-catenins. Here we show that A-CAM (N-cadherin), another member of this gene family, also associates with catenins suggesting that this complex formation may be a general property of the cadherins. For uvomorulin it has been found that this association with catenins is of crucial importance for the adhesive function, but little is known about the molecular organization of the uvomorulin-catenin complex. Using a combination of biochemical analyses we show that a single complex is composed of one molecule of uvomorulin, one or two molecules of beta-catenin, and one molecule of alpha-catenin. Furthermore, beta-catenin seems to interact more directly with uvomorulin. In pulse-chase experiments beta-catenin is already associated with the 135-kD uvomorulin precursor molecule but the assembly of the newly synthesized alpha-catenin into the complex is only detected around the time of endoproteolytic processing.
The adenomatous polyposis coli gene (APC) is a tumor suppressor gene that is inactivated in most colorectal cancers. Mutations of APC cause aberrant accumulation of beta-catenin, which then binds T cell factor-4 (Tcf-4), causing increased transcriptional activation of unknown genes. Here, the c-MYC oncogene is identified as a target gene in this signaling pathway. Expression of c-MYC was shown to be repressed by wild-type APC and activated by beta-catenin, and these effects were mediated through Tcf-4 binding sites in the c-MYC promoter. These results provide a molecular framework for understanding the previously enigmatic overexpression of c-MYC in colorectal cancers.
Mutations in the adenomatous polyposis coli or beta-catenin gene lead to cytosolic accumulation of beta-catenin and, subsequently, to increased transcriptional activity of the beta-catenin-T cell-factor/lymphoid-enhancer-factor complex. This process seems to play an essential role in the development of most colorectal carcinomas. To identify genes activated by beta-catenin overexpression, we used colorectal cell lines for transfection with the beta-catenin gene and searched for genes differentially expressed in the transfectants. There are four genes affected by beta-catenin overexpression; three overexpressed genes code for two components of the AP-1 transcription complex, c-jun and fra-1, and for the urokinase-type plasminogen activator receptor (uPAR), whose transcription is activated by AP-1. The direct interaction of the beta-catenin-T cell-factor/lymphoid-enhancer-factor complex with the promoter region of c-jun and fra-1 was shown in a gel shift assay. The concomitant increase in beta-catenin expression and the amount of uPAR was confirmed in primary colon carcinomas and their liver metastases at both the mRNA and the protein levels. High expression of beta-catenin in transfectants, as well as in additionally analyzed colorectal cell lines, was associated with decreased expression of ZO-1, which is involved in epithelial polarization. Thus, accumulation of beta-catenin indirectly affects the expression of uPAR in vitro and in vivo. Together with the other alterations, beta-catenin accumulation may contribute to the development and progression of colon carcinoma both by dedifferentiation and through proteolytic activity.
beta-Catenin plays a dual role in the cell: one in linking the cytoplasmic side of cadherin-mediated cell-cell contacts to the actin cytoskeleton and an additional role in signaling that involves transactivation in complex with transcription factors of the lymphoid enhancing factor (LEF-1) family. Elevated beta-catenin levels in colorectal cancer caused by mutations in beta-catenin or by the adenomatous polyposis coli molecule, which regulates beta-catenin degradation, result in the binding of beta-catenin to LEF-1 and increased transcriptional activation of mostly unknown target genes. Here, we show that the cyclin D1 gene is a direct target for transactivation by the beta-catenin/LEF-1 pathway through a LEF-1 binding site in the cyclin D1 promoter. Inhibitors of beta-catenin activation, wild-type adenomatous polyposis coli, axin, and the cytoplasmic tail of cadherin suppressed cyclin D1 promoter activity in colon cancer cells. Cyclin D1 protein levels were induced by beta-catenin overexpression and reduced in cells overexpressing the cadherin cytoplasmic domain. Increased beta-catenin levels may thus promote neoplastic conversion by triggering cyclin D1 gene expression and, consequently, uncontrolled progression into the cell cycle.
Tissue microarrays allow high-throughput molecular profiling of cancer specimens by immunohistochemistry. Phenotype information of sections from arrayed biopsies on a multitissue block needs to be representative of full sections, as protein expression varies throughout the entire tumor specimen. To validate the use of tissue microarrays for immunophenotyping, we studied a group of 59 fibroblastic tumors with variable protein expression patterns by immunohistochemistry for Ki-67, p53, and the retinoblastoma protein (pRB). Data on full tissue sections were compared to the results of one, two, and three 0.6-mm core biopsies per tumor on a tissue array. Ki-67 and p53 staining was read as two categories (positive or negative). Concordance for this staining between tissue arrays with triplicate cores per tumor and full sections were 96 and 98%, respectively. For pRB staining was read as three categories (high, moderate, or negative), where concordance was 91%. The use of three cores per tumor resulted in lower numbers of lost cases and lower nonconcordance with standard full sections as compared to one or two cores per tumor. Correlations between phenotypes and clinical outcome were not significantly different between full section and array-based analysis. Triplicate 0.6-mm core biopsies sampled on tissue arrays provide a reliable system for high-throughput expression profiling by immunohistochemistry when compared to standard full sections. Triplicate cores offer a higher rate of assessable cases and a lower rate of nonconcordant readings than one or two cores. Concordance of triplicate cores is high (96 to 98%) for two category distinction and decreases with the complexity of the phenotypes being analyzed (91%).
Two distinct calcium-sensitive cell-cell adhesion molecules were identified in human epithelial tissues and carcinomas using two monoclonal antibodies raised against vulvar epidermoid carcinoma A-431 and human mammary carcinoma MCF-7 and selected on the basis of their activities to disrupt cell-cell adhesion. In immunoblot analysis, these antibodies, designated NCC-CAD-299 and HECD-1, detected main bands of Mr 118,000 and 124,000, respectively. Purified tryptic fragments of the antigen recognized by NCC-CAD-299 showed cross-reactivity with a rabbit antiserum against mouse P-cadherin, indicating that this molecule was the human homologue of P-cadherin. On the other hand, the antigen recognized by HECD-1 showed essentially the same tissue distribution pattern as E-cadherin in the mouse, suggesting that this molecule is the human homologue of E-cadherin. Availability of these monoclonal antibodies to human P- and E-cadherin allowed us to examine their distributions in human tissues immunohistochemically. Both antigens were detected in epithelial tissues, but they showed distributions that were distinct from each other. The antigen recognized by HECD-1 was expressed in almost all epithelial tissues, while distribution of the other one recognized by NCC-CAD-299 was restricted to the basal or lower layers of stratified epithelia in which both antigens were coexpressed. Moreover, immunohistochemical examination of 44 lung carcinomas showed that both molecules were coexpressed in all of them, and suggested that expression of P-cadherin was closely related to the differentiation of carcinoma cells.
Background:
Five-year survival rates after resection of liver metastases from colorectal carcinoma are close to 25%. Recurrences occur in two-thirds of the patients after surgery. Selection of patients likely to benefit from surgery remains controversial and subjective.
Methods:
Data from 1568 patients with resected liver metastases from colorectal carcinoma were collected. The prognostic value of different factors was studied through uni- and multivariate analyses. A scoring system was developed including the most relevant factors.
Results:
Two- and 5-year survival rates were 64% and 28%, respectively, and were affected by: age; size of largest metastasis or CEA level; stage of the primary tumor; disease free interval; number of liver nodules; and resection margin. Giving one point to each factor, the population was divided into three risk groups three risk groups with different 2-year survival rates: 0-2 (79%), 3-4 (60%), 5-7 (43%).
Conclusions:
A simple prognostic scoring system was proposed to evaluate the chances for cure of patients after resection of liver metastases from colorectal carcinoma. The comparison between expected survival and estimated operative risk can help determine on an objective basis whether surgery is worthwhile. This system needs further prospective validation.
Inactivation of the adenomatous polyposis coli (APC) tumor suppressor protein is responsible for both inherited and sporadic forms of colon cancer. Growth control by APC may relate to its ability to downregulate beta-catenin post-translationally. In cancer, mutations in APC ablate its ability to regulate beta-catenin, and mutations in beta-catenin prevent its downregulation by wild-type APC. Moreover, signaling by the protein product of the wnt-1 proto-oncogene upregulates beta-catenin and promotes tumorigenesis in mice. In a Xenopus developmental system, Wnt-1 signaling was inhibited by Axin, the product of the murine fused gene. This suggests a possible link between Axin, the Wnt-1 signaling components beta-catenin and glycogen synthase kinase 3 beta (GSK3 beta), and APC.
Human Axin (hAxin) binds directly to beta-catenin, GSK3 beta, and APC in vitro, and the endogenous proteins are found in a complex in cells. Binding sites for Axin were mapped to a region of APC that is typically deleted due to cancer-associated mutations in the APC gene. Overexpression of hAxin strongly promoted the downregulation of wild-type beta-catenin in colon cancer cells, whereas mutant oncogenic beta-catenin was unaffected. The downregulation was increased by deletion of the APC-binding domain from Axin, suggesting that APC may function to derepress Axin activity. In addition, hAxin dramatically facilitated the phosphorylation of APC and beta-catenin by GSK3 beta in vitro.
Axin acts as a scaffold upon which APC, beta-catenin and GSK3 beta assemble to coordinate the regulation of beta-catenin signaling.
E-cadherin and the associated catenin complex have been recognised as performing a key role in cell adhesion. Loss of cell adhesion is seen as a key step in the cascade leading to tumour metastasis. The ability of both extra- and intracellular factors to regulate E-cadherin-mediated cell adhesion in physiological processes has provided insight into both the interactions of the E-cadherin–catenin complex, and possible mechanisms utilised by tumours in the process of metastasis. The interaction of the E-cadherin–catenin complex with various regulating factors, their effect on cell signalling pathways, and the relationship with the metastatic potential of tumours are reviewed.
Intercellular adhesion mediated by the E-cadherin/catenin complex is a prerequisite for epithelial integrity and differentiation. In carcinomas, E-cadherin function is frequently disturbed, and has been suggested to increase invasion and metastasis of tumour cells. β-catenin has also been implicated in signaling pathways essential for tumour formation. We analysed the E-cadherin/catenin adhesion system of colorectal tumours at different clinical stages. In primary carcinomas (n=91), there was a frequent reduction in E-cadherin (44%) and α-catenin expression (36%). In contrast, β-catenin and γ-catenin expression were seldom reduced (4% and 15%, respectively). Similar expression patterns were observed in liver metastases from unrelated colorectal tumours (n=27). There was a significant relationship between loss of E-cadherin and α-catenin expression and poorly differentiated (G3–4) tumours. Our results suggest that reduction of E-cadherin/α-catenin expression is a frequent event in primary and metastatic colorectal carcinomas. Furthermore, β-catenin expression remains normal in colorectal cancer, suggesting the essential role of β-catenin in signaling pathways
Background: Local recurrence after resection of rectal carcinoma is a difficult clinical problem that adversely affects both survival and quality of life. Surgical resection is possible for a subset of patients with localized recurrences. We reviewed our experience with surgical salvage of recurrent rectal carcinoma, to determine predictors of resectability and postsalvage survival rates.
Methods: A 10-year, retrospective analysis of 131 patients who underwent exploration with curative intent for local recurrence after radical resection of rectal carcinomas, in a single referral institution, was performed. Preoperative and pathological factors were examined for their ability to predict postresection survival rates and resectability.
Results: The overall 5-year survival rate for patients who underwent exploration with curative intent was 24%. Resection of recurrent disease was possible for 103 of 131 (79%) patients, with a resulting 5-year survival rate of 31%. Patients who were treated initially with abdomino-perineal resection (n = 35) presented later and were less likely to have resectable tumors than were those treated initially with some form of sphincter-preserving resection (n = 96). Among patients who could undergo resection, normal carcinoembryonic antigen levels and recurrent disease limited to the bowel wall were both favorable features.
Conclusions: Surgical salvage of local recurrence after radical resection of rectal carcinoma can be performed safely and can result in substantial long-term survival benefits for selected patients.
Mutations in the adenomatous polyposis coli or beta-catenin gene lead to cytosolic accumulation of beta-catenin and, subsequently, to increased transcriptional activity of the beta-catenin-T cell-factor/lymphoid-enhancer-factor complex. This process seems to play an essential role in the development of most colorectal carcinomas. To identify genes activated by beta-catenin overexpression, we used colorectal cell lines for transfection with the beta-catenin gene and searched for genes differentially expressed in the transfectants. There are four genes affected by beta-catenin overexpression; three overexpressed genes code for two components of the AP-1 transcription complex, c-jun and fra-1, and for the urokinase-type plasminogen activator receptor (uPAR), whose transcription is activated by AP-1. The direct interaction of the beta-catenin-T cell-factor/lymphoid-enhancer-factor complex with the promoter region of c-jun and fra-1 was shown in a gel shift assay. The concomitant increase in beta-catenin expression and the amount of uPAR was confirmed in primary colon carcinomas and their liver metastases at both the mRNA and the protein levels. High expression of beta-catenin in transfectants, as well as in additionally analyzed colorectal cell lines, was associated with decreased expression of ZO-1, which is involved in epithelial polarization. Thus, accumulation of beta-catenin indirectly affects the expression of uPAR in vitro and in vivo. Together with the other alterations, beta-catenin accumulation may contribute to the development and progression of colon carcinoma both by dedifferentiation and through proteolytic activity.
Control of stability of β-catenin is central in the wnt signaling pathway. Here, the protein conductin was found to form a
complex with both β-catenin and the tumor suppressor gene product adenomatous polyposis coli (APC). Conductin induced β-catenin
degradation, whereas mutants of conductin that were deficient in complex formation stabilized β-catenin. Fragments of APC
that contained a conductin-binding domain also blocked β-catenin degradation. Thus, conductin is a component of the multiprotein
complex that directs β-catenin to degradation and is located downstream of APC. InXenopus embryos, conductin interfered with wnt-induced axis formation.
β-catenin plays a fundamental role in the regulation of the E-cadherin-catenin cell adhesion complex. It also functions in growth signalling events, independently of the cadherin-catenin complex, and these signalling pathways are disturbed in colorectal cancer. Mutations in either the APC or β-catenin genes in colorectal cancer cells result in up-regulation of protein expression and subsequent cytoplasmic and nuclear distribution of β-catenin. In this study, we examined β-catenin expression in 47 primary colorectal tumors and the corresponding liver metastases. Immunohistochemical studies demonstrated loss of membranous β-catenin expression in 26% of primary tumors and 60% of liver metastases and a concomitant increase in cytoplasmic and nuclear staining. Widespread nuclear expression of β-catenin was found in 64% of primary tumors and 21% of liver metastases. No associations were found between any form of β-catenin expression and either tumor stage or tumor grade. Cellular distribution of β-catenin was also examined by detergent extraction and Western blot analysis in 16 primary tumors and 23 liver metastases. This analysis showed that most tumors demonstrated reduced β-catenin in the cytoskeletal fraction and increased β-catenin in the cytosolic fraction. Furthermore, 3 liver metastases were found to contain a truncated β-catenin protein of approximately Mr 80,000. Immunoprecipitation studies showed that the truncated β-catenin proteins only bound weakly to E-cadherin and β-catenin compared with non-truncated β-catenin. These results demonstrate gross alterations in the cellular distribution of β-catenin in primary colorectal cancers with metastatic potential, as well as in the metastatic tumors. These changes may be the consequence of APC or β-catenin gene mutations, or possibly result from a post-translational modification of the E-cadherin-catenin complex. Int. J. Cancer 82:504–511, 1999. © 1999 Wiley-Liss, Inc.
E-cadherin (E-CD), a Ca(2+)-dependent adhesion molecule, plays a major role in the maintenance of intercellular junctions in normal epithelial cells in most organs. The expression of E-CD in human carcinoma samples (esophagus, stomach, and breast) was investigated using immunohistochemical staining, which was performed on surgical specimens using a monoclonal antibody for human E-CD. E-cadherin was strongly expressed in all normal epithelium examined. However E-CD expression in primary tumors of esophagus (11 of 15: 73%), stomach (5 of 20: 25%), and breast (9 of 20: 45%) was reduced, and 68% of these (esophagus: 8 of 11, stomach: 4 of 5, breast: 5 of 9) displayed heterogeneous E-CD expression. In some tumor cells with reduced E-CD expression, E-CD molecules were located in the cell cytoplasm. These results indicate that there are human cancer cells in which E-CD-related intercellular adhesion is impaired.
From 1960 to 1988, 266 patients underwent resection of colorectal secondaries to the liver with curative intent. All patients were followed until April 1, 1990, or death, with a median follow-up time of 52 months. Nine patients with minimal macroscopic residual disease and 38 patients with all gross tumor removed but positive margins showed a poor prognosis with a median survival time of 13.3 months, the longest being 42 months. Of the 219 patients having potentially curative resection, 12 patients died postoperatively (5.5%). Actuarial 5, 10 and 20-year survival for the remaining 207 patients was 39%, 28%, and 18%, respectively. At April 1, 1990, 77 patients were alive with no evidence of disease for up to 24 years, and 12 patients had died without recurrence. The following factors were associated with less favorable crude survival: presence and extent of mesenteric lymph node involvement (p = 0.0003), grade III/IV primary tumor (p = 0.035), synchronous diagnosis of metastases (p = 0.017), satellite metastases (p = 0.0003), limited resection margins (p = 0.019), and nonanatomic procedures (p = 0.013). With respect to disease-free survival, grading of the primary (p = 0.055) and the extent of clear margins (p = 0.019) failed to achieve statistical significance. Two other criteria are commonly recommended as absolute contraindications to hepatic resection: extrahepatic disease and the presence of four or more independent metastases. A radical excision of all detectable disease may rarely be possible in these circumstances. Nevertheless, within the curative settings, no significant predictive value regarding either overall or disease-free survival was found in this series. Three corresponding "high risk" patients are alive without disease at 5 to 11 years from hepatic resection. These patients with more advanced intrahepatic or concomitant limited extrahepatic disease require a particularly thorough diagnostic work up. As no superior therapeutic alternative is currently available, an aggressive surgical approach may occasionally be justified, and may, in a small portion, result in definite tumor control.
The expression pattern of two Ca2(+)-dependent intercellular adhesion molecules, E- and P-cadherin, in 54 surgically resected gastric adenocarcinomas was examined immunohistochemically. E-cadherin was expressed uniformly at the cell-cell borders of most of the differentiated and adherent-type undifferentiated gastric adenocarcinomas, showing that E-cadherin serves as the main cadherin molecule responsible for intercellular binding in these carcinomas. Scattered-type undifferentiated gastric adenocarcinomas which apparently lacked this tight intercellular adhesion were divisible into two groups on the basis of E-cadherin expression. In a minor group composed of 4 carcinomas, E-cadherin could not be detected, suggesting that the absence of E-cadherin made the cancer cells separate. In contrast, cancer cells of 19 carcinomas which belonged to the major group showed similar scattering but had definite expression of E-cadherin on their cell surfaces, suggesting that there was some mechanism(s) disturbing the function of E-cadherin in these carcinomas. However, immunoblotting showed no evidence of gross alterations of the E-cadherin molecule, such as partial deletion, in these carcinomas. P-cadherin was expressed in 29 (54%) of the examined gastric carcinomas, and the expression was unstable in most of them, a characteristic feature compared with the stable expression of E-cadherin. Since P-cadherin is known to be expressed temporarily in the foregut during embryogenesis and was proved to be occasionally expressed, although weakly, in the proliferative zone of noncancerous gastric epithelia in this study, expression of P-cadherin in gastric carcinomas may be an oncofetal phenomenon and/or may reflect their marked proliferative potential.
Current data indicate that liver resection is the only available treatment that regularly produces long-term survival with possible cure in patients with metastatic colorectal carcinoma to the liver. Although a number of clinical or pathologic factors predicts a poor outcome, the only absolute contraindications to liver resection are general health incompatible with recovery from major hepatic resection or clear evidence of wide dissemination of disease. Important areas for future study include the potential role of adjuvant regional chemotherapy after resection and cryoablation of "close" margins. For patients with unresectable disease, operative therapy also plays an important role. Multiple operative modalities hold promise in palliative treatment in the setting of clinically incurable disease. It is imperative that a large randomized trial of regional chemotherapy be performed allowing no crossover and with mortality as an endpoint. Additionally, the role of cryoablation begs systematic investigation to ensure proper use of this modality.
Classical cadherins are complexed via their cytoplasmic domains with alpha-, beta- and gamma-catenin. This complex formation links cadherins to the actin filament network and to other transmembrane and cytoplasmic proteins. alpha-Catenin is homologous to vinculin, and beta-catenin to the product of the Drosophila gene armadillo, while gamma-catenin seems to be identical to plakoglobin. Catenins are part of a higher order protein structure that is of crucial importance for the adhesive function of cadherins. A working model of the construction and regulation of this multiprotein interaction is proposed.
To determine the major factors governing patient outcome after hepatic resection of metastatic colorectal cancer and to formulate criteria for optimal resection.
We reviewed records of 74 patients (44 men, 30 women) who underwent resection of colorectal liver metastases.
Sex, age, primary tumor location; Dukes tumor stage; disease-free interval after primary resection (synchronous vs metachronous); location, number, size, and distribution of liver metastases; operative complications; and mortality.
The primary tumor location was rectosigmoid in 46 patients and the colon in the others. The tumor stage was Dukes A in one patient, Dukes B in 16, Dukes C in 31, and Dukes D (synchronous metastases) in 26. The disease-free interval was less than 12 months in 38 patients and 12 months or more in 36. The location of the metastases was the right lobe in 42 patients, left lobe in 22, and bilateral in seven. The cancer was unilobar in 55 patients and bilobar in 18. Surgical resection included wedge resection in 23 patients, segmentectomy in 30, lobectomy in seven, and trisegmentectomy in 12. The number of lesions resected was one in 50 patients, two or three in 18, and four or more in five. Nine patients had repeated liver resections because of recurrence. There were five postoperative deaths within 60 days (7%), four of which occurred after extended resection and were complicated by delayed liver failure and multisystem failure. An additional death occurred at 65 days after an apparently uneventful initial convalescence. Overall median survival was 35 months; actuarial 5- and 10-year survival rates were 24% and 12% respectively. There were significant relationships with survival (P<.05) for the number of metastases (three or fewer vs four or more), bilobar vs unilobar metastases, and extent of liver resection (wedge and segmental vs lobectomy and trisegmentectomy). A multiple logistic regression model (multivariate analysis) showed a significant correlation with survival (P<.05) for distribution of metastases (bilobar vs unilobar) and extent of resection (wedge and segmental vs lobectomy and trisegmentectomy).
Patient selection for hepatic resection of colorectal cancer metastases based on standard clinical and tumor outcome variables should be expected to achieve long-term survival with low morbidity and mortality in bilobar disease or extended resection should generally be avoided, especially in medically compromised patients.
E-cadherin is crucial to the intercellular adherens junctions which are involved in the organisation and maintenance of epithelial structure and suppression of tumour invasion. E-cadherin is associated with the actin cytoskeleton via cytoplasmic proteins, including alpha-, beta- and gamma-catenins, which together form the cadherin/catenin complex. To evaluate changes of the molecules of the cadherin/catenin complex in colorectal carcinogenesis, seventy-four sporadic adenomas, samples of histologically normal epithelium adjacent to 65 adenomas, and 52 carcinomas arising in adenomas were investigated by immunohistochemistry. All normal epithelial cells showed a uniform membranous staining pattern for E-cadherin, alpha-, beta-, and gamma-catenin. Decreased expression of all 4 proteins occurred in parallel in adenomas and carcinomas (in all cases, p < 10(-5). Decreased expression of the cadherin/catenin complex in adenomas was associated with increasing severity of dysplasia (p < 0.001, for E-cadherin, alpha-, and gamma-catenin, p < 0.005 for beta-catenin). Carcinomas displayed significantly reduced expression of the cadherin/catenin complex compared with their associated adenomas (all p < 0.001). The results directly confirm that colorectal tumour progression and invasion is associated with disruption of the cadherin/catenin complex and suggest that the genetic changes and transcriptional modulation of catenins underlying this progression may affect all members of the complex.
Cadherins form complexes with groups of cytoplasmic proteins, such as alpha-, beta-, and gamma-catenins, that link the cadherin molecule to the cytoskeleton. In this study, we conducted an immunohistochemical investigation of E-cadherin and alpha-catenin expression in 100 tissue samples obtained from colorectal cancer patients undergoing surgical treatment. Reduced expression of alpha-catenin was observed in 56 (56%) of the cases and found to be significantly correlated with the depth of invasion of the patients' colorectal cancer and its metastasis to lymph nodes and liver. In contrast, E-cadherin expression was reduced in 29 (29%) of the cases and was not significantly correlated with either depth of invasion or metastasis. Although the levels of expression of these proteins were positively correlated, coexpression pattern analysis showed that invasion and metastasis were correlated with a reduction of alpha-catenin expression regardless of the status of E-cadherin staining. Thus, to predict tumor invasion and metastasis in colorectal adenocarcinoma, it is useful to investigate not just the expression of E-cadherin but also the expression of alpha-catenin.
The interaction of the adenomatous polyposis coli (APC) tumor-suppressor protein and the intracellular cell-adhesion protein beta-catenin is crucial for the development of colorectal tumors. Since functional nuclear complexes of beta-catenin with transcription factors have been identified recently, the knowledge of level and distribution of beta-catenin in sporadic colorectal tumors will give important insights into the intracellular mechanism of sporadic colorectal tumor initiation and progression. In contrast to the familiar adenomatous polyposis syndrome and to the majority of sporadic colorectal tumors, Peutz-Jeghers (PJ) syndrome is not caused by mutations in the APC gene. Since PJ syndrome is an inherited disease with an increased risk for gastrointestinal adenocarcinoma, whether beta-catenin plays a similarly important role for the development of PJ polyps should be further investigated. For these reasons we analyzed the distribution of beta-catenin in a total of 60 sporadic colorectal tumors at different stages of progression and in 6 PJ polyps. In addition to the localization at the cell-to-cell border membranes, fluorescence immunohistochemistry revealed a nuclear accumulation of beta-catenin in single tumor cells of 10/14 small adenomas with mild dysplasia and in 14/16 adenomas with moderate dysplasia. Further tumor progression is accompanied by an expansion of cells with increased level of nuclear and cytoplasmic beta-catenin. These cells were observed in 5/16 adenomas with moderate dysplasia and in 15/15 adenomas with severe dysplasia. In all adenocarcinomas investigated, as well as in the corresponding lymph node metastases, a sub-population of tumor cells exhibited a remarkably increased level of beta-catenin within the entire cytoplasm and the nucleus. In contrast to the situation in sporadic colorectal tumors, nuclear and cytoplasmic beta-catenin was not increased in PJ polyps. These results point to an extensive redistribution of beta-catenin, which starts early in colorectal tumorigenesis. The nuclear accumulation in single cells of small adenomas can be considered as the first visible sign of the loss of APC function. Thus the immunohistochemical detection of beta-catenin distribution could serve as a criterion for estimating the malignant potential in the clinico-pathological evaluation of colon tumors during their early progression.
Most colorectal cancers have loss-of-function mutations in the adenomatosis polyposis coli (APC) tumor suppressor gene. This leads to the accumulation of nuclear beta-catenin, which, together with the DNA-binding protein TCF-4, functions as a transcriptional activator. The recently defined target genes c-myc, cyclin D1, and matrilysin are responsible for tumor proliferation or malignant progression and explain the oncogenic potential of nuclear beta-catenin. To investigate its role in early colon carcinogenesis, we analyzed the expression of beta-catenin, its target gene c-myc, and the proliferative activity in 88 colorectal adenomas of varying size and grade of dysplasia. The results revealed i) the most significant correlation of nuclear beta-catenin and c-myc expression was not with the grade of dysplasia but with the size of the colon adenoma; ii) perfect correlation of nuclear beta-catenin and c-myc expression; iii) no significant correlation of adenoma size with the proliferative activity; and iv) no significant correlation of proliferative activity and the nuclear expression of beta-catenin and c-myc. These results imply that APC mutations have additional beta-catenin-independent functions; APC mutations alone are not sufficient for nuclear overexpression of beta-catenin; and nuclear beta-catenin has additional important functions for exceeding a threshold tumor size.
The adenomatous polpyposis coli (APC) protein is mutated in most colorectal tumours. Nearly all APC mutations are truncations, and many of these terminate in the mutation cluster region located halfway through the protein. In cancer cells expressing mutant APC, beta-catenin is stabilized and translocates into the nucleus to act as a transcriptional co-activator of T-cell factor. During normal development, APC also promotes the destabilization of beta-catenin and Drosophila Armadillo. It does so by binding to the Axin complex which earmarks beta-catenin/Armadillo for degradation by the proteasome pathway. APC has a regulatory role in this process, which is poorly understood. Here we show that APC contains highly conserved nuclear export signals 3' adjacent to the mutation cluster region that enable it to exit from the nucleus. This ability is lost in APC mutant cancer cells, and we provide evidence that beta-catenin accumulates in the nucleus as a result. Thus, the ability of APC to exit from the nucleus appears to be critical for its tumour suppressor function.
Reduced expressions of cell adhesion molecules (E-cadherin, alpha-catenin, and beta-catenin) has been reported to be associated with tumor metastasis. However, the clinical significance of such adhesion molecules in the metastatic foci remains unclear. In this study, we evaluated the prognostic significance of E-cadherin, alpha-catenin, and beta-catenin expressions in the metastatic foci of patients with colorectal carcinoma.
The expressions of E-cadherin, alpha-catenin, and beta-catenin were detected immunohistochemically in 105 primary tumors, in 30 metastatic lymph nodes, and 13 metastatic liver tumors from consecutive patients with colorectal carcinoma.
Reduced normal expression of E-cadherin, alpha-catenin, and beta-catenin in comparison with normal epithelium was detected in 78 primary tumors, respectively. Patients who had tumors with reduced expression of adhesion molecules showed unfavorable prognosis and the reduced expression of adhesion molecules was detected as one of the independent prognostic factors for patients with colorectal carcinoma. In 30 patients with lymph node metastasis, the increased expression of adhesion molecules in metastatic lymph nodes compared with primary tumors was detected in 13 patients. The prognosis of these 13 patients was poorer than that of remaining 17 patients (P = 0.0296). Also, in 13 patients with liver metastasis, even no significant difference was observed, the mean survival time of 6 patients who had metastatic liver tumors with increased expression of adhesion molecules (10 months) was shorter than that of the remaining 7 patients (16 months; P = 0.1718).
These results suggest that increased expression of the cadherin-catenin cell-cell adhesion system in metastatic foci may play an important role in progression of metastatic colorectal carcinomas.
Tissue microarray technology enables the analysis of hundreds of specimens by arranging numerous 0.6-mm tissue core biopsy specimens into a single paraffin block. Validation studies are necessary to evaluate the representativeness of small disks taken from the original tissue. We validated the tissue microarray technology in colorectal carcinoma by analyzing the immunohistochemical expression of proteins involved in the two main pathways of colorectal carcinogenesis: p53 protein for loss of heterozygosity tumors, hMLH1 and hMSH2 proteins for microsatellite instability (MSI) tumors. We compared in 30 colorectal carcinomas (15 MSI(-) and 15 MSI(+)), 8 microarrays disks, and the whole section of the block from which they were derived. Tumoral tissue was present in 95.7% of the microarray disks. The analysis of three disks per case was comparable to the analysis of the whole section in 99.6% (p53), 98.8% (hMLH1), and 99.2% (hMSH2) of cases. In the second part we applied the tissue microarray technology to 263 consecutive cases of colorectal carcinoma, sampled by three cores. We showed that 48.5% overexpressed p53 and 8.7% lost hMLH1 or hMSH2. Tissue microarray technology, validated in colorectal carcinoma, appears as a useful research tool for rapid analysis of the clinical interest of molecular alterations.
E-cadherin and its associated intracellular molecules, catenins, are important for cell-cell adhesion. Impaired expression of these molecules are frequently observed in several cancers. E-cadherin and beta-catenin are often expressed in non-small cell lung cancers. The aim of this study was to investigate the expressions of E-cadherin and beta-catenin and their significance as prognostic markers in pathological stage I non-small cell lung cancer.
Paraffin embedded tumor tissue blocks were obtained from 141 patients who underwent resection without preoperative radiotherapy or chemotherapy with pathological stage I non-small cell lung cancer. Tumor samples were prepared in tissue microarrays and they were stained by immunohistochemistry with antibodies against E-cadherin and beta-catenin. The expressions of E-cadherin and beta-catenin were analyzed with relation to the clinico-pathological data. The median follow-up period of the patients was 41 months (range, 2-88 months).
Preserved expressions of E-cadherin and beta-catenin were observed in the membrane and the cytoplasm of normal epithelial cells and tumor cells. Absent or reduced expression for E-cadherin and beta-catenin were observed in 60% and 45% of all the patients, respectively. There was a significant positive correlation between E-cadherin and beta-catenin expression (P<0.01). Absent or reduced expression of E-cadherin was observed in 72.5%, 36.6%, and 60.0% of squamous cell carcinoma, adenocarcinoma, and bronchioloalveolar carcinoma, respectively. There was a significant decrease of E-cadherin expression in squamous cell carcinoma compared to adenocarcinoma (P<0.01). Patients with reduced expression of beta-catenin had poor recurrence free survival in adenocarcinoma, but not in squamous cell carcinoma.
Decreased expressions of E-cadherin and beta-catenin were closely correlated in resected stage I non-small cell lung cancer. Reduced expression of E-cadherin and beta-catenin indicates tumor cell dedifferentiation and reduced expression of beta-catenin had poor recurrence free survival in adenocarcinoma of the resected stage I non-small cell lung cancer.
Through the use of molecular markers, it may be possible to identify aggressive tumor phenotypes and tailor therapies to treat them. This approach would be particularly useful for stage II colon cancer. The purpose of this study was to define the prognostic value of epidermal growth factor receptor (EGFR), c-MET, beta-catenin, and p53 protein expression in TNM stage II colon cancer using tissue microarray technology.
In this study, we retrospectively analyzed, resected, and otherwise untreated paraffin-embedded specimens from 134 consecutive patients with Tumor-Node-Metastasis stage II colonic carcinomas for EGFR, c-MET, beta-catenin, and p53 protein expression by immunohistochemistry.
Thirty-five percent, 77, and 65% of tumors exhibited strong (+2 and +3 immunopositivity) expression of EGFR, c-MET, and beta-catenin, respectively. Fifty-four percent exhibited nuclear staining for p53 in >10% of the tumor cells. Univariate analysis revealed that increased nuclear p53 expression (P = 0.001), strong membranous EGFR expression (P = 0.04), and lymphovascular invasion (P = 0.01) were significantly related to disease recurrence and that p53 (P = 0.02) and EGFR (P = 0.05) expression were associated with decreased survival. Increased nuclear p53 expression also correlated with the presence of distal metastasis (P = 0.027). No significant association was seen between c-MET expression and prognosis, whereas a strong trend was detected between loss of beta-catenin (P = 0.065) expression and poor outcome. Multivariate analysis indicated that p53 (P = 0.04), EGFR (P = 0.05), and lymphovascular invasion (P = 0.03) were independent predictors of recurrence and that p53 (P = 0.02) and EGFR (P = 0.01) expression were both associated with poor survival.
This retrospective tumor microarray study, restricted to Tumor-Node-Metastasis stage II colon cancer patients who did not undergo adjuvant therapy, supports the use of EGFR and p53 as biological markers, which may assist in predicting disease recurrence and survival.
We utilized the high-throughput tissue microarray method to characterize immunohistochemical expression patterns with correlations to prognosis in rectal cancer. Immunostaining for the markers Ki-67, Bcl-2, p53, EGFR, E-cadherin, beta-catenin, MLH1 and MSH2 was performed in 269 rectal cancers. Expression profiles were correlated to metastasis-free survival. Immunostaining revealed frequent upregulation and/or aberrant staining patterns for several of the markers, but Ki-67, p53, Bcl-2 and EGFR did not show any correlation to prognosis. However, reduced membranous staining for beta-catenin (p = 0.04), lack of cytoplasmic staining for beta-catenin (p = 0.04), reduced membranous staining for E-cadherin (p = 0.02) and lack of cytoplasmic staining for E-cadherin (p = 0.02) correlated with metastatic disease. Multivariate analysis including the factors Dukes' stage and tumor differentiation grade demonstrated increased risk of metastatic disease in tumors with lack of cytoplasmic staining for beta-catenin (HR = 3.1, p = 0.02), reduced membranous staining for beta-catenin (HR = 1.7, p = 0.06) and reduced membranous staining for E-cadherin (HR = 2.1, p = 0.06). Loss of MMR protein expression was confirmed to be a rare event in rectal cancer with loss of MLH1 staining in 3% and MSH2 in 1% of the tumors. The lack of prognostic information contributed by most of these markers suggests that single markers for prognosis may be of limited value in rectal cancer. However, altered expression of beta-catenin and E-cadherin correlated with metastatic disease, and these markers may have prognostic importance in rectal cancer.
Indicators of prognosis after hepatic resection for colorectal secondaries
- Scheele
Expression of E- and P-cadherin in gastric carcinoma
- Shimoyama
Molecular organization of the uvomorulin–catenin complex
- Ozawa