[show abstract][hide abstract] ABSTRACT: Identification of secreted proteins of lung cancer could provide new candidates of serum biomarkers for cancer diagnosis or targets for therapeutic intervention. In this study, we developed a novel strategy that combined functional monoclonal antibody library screening technique and mass spectrometry to identify functional secreted proteins. BALB/c mice were immunized with cancer cells isolated from fresh human lung cancer tissues. The monoclonal antibody library containing 1160 mAbs was established with the mouse spleen cells, whose serum had most anti-proliferative effect on lung cancer cells. Monoclonal antibodies were subjected to an immunoreactive and functional screen and monoclonal antibodies that reacted strongly with secreted proteins in condition medium and lung cancer tissues with high inhibotion of cell proliferation were selected. Antigens that recognized by antibodies were obtained by immunoprecipitation and then identified by mass spectrometry. Mac-2-binding protein (Mac-2BP), the antigen of 13H3 antibody was identified using this approach. Functional studies demonstrated that the 13H3 antibody suppressed lung cancer cell lines ANIP-973 and A549 proliferation in vitro and inhibit ANIP973 xenograft tumors growth in vivo by inducing cell-cycle arrest at G1 phase, with up-regulation of p21and downregulation of cyclin D1. Moreover, the serum level of Mac-2BP was significantly higher in lung cancer patients than healthy controls. At a cutoff value of 6ug/ml, Mac-2BP might be a diagnostic biomarker of lung cancer, especially for SCLC. Mac-2BP concentrations of 6ug/ml or higher was associated with poor overall survival in univariate analysis, and was an independent predictor in the multivariate COX analysis. Together, these results firstly demonstrated that Mac-2BP can be used as a therapeutic target and potential biomarker for lung cancer. Our strategy is feasible, which may facilitate the identification of novel secreted biomarkers of lung cancer.
[show abstract][hide abstract] ABSTRACT: This study aimed to identify novel molecular markers for the early detection of colorectal cancer liver metastasis.
Genes related to hepatic metastasis were screened from the Oncomine database. The candidate markers were tested by immunohistochemistry, and their predictive accuracy was assessed by the cross-validation method and an independent test set.
We got three datasets containing 2,973 genes that were highly expressed in primary colon cancer tissues compared with non-metastatic colon cancer tissues and identified 7 candidate molecules for immunohistochemical validation. A total of 213 colorectal cancer samples were randomly divided into a training set (113 cases) and a blind testing set (100 cases). In the training set, immunohistochemical analysis showed that HP, OPN, and PTGIS expression were significantly higher in the hepatic metastasis group than in the non-metastasis group. Logistic regression analysis showed that HP and OPN levels in primary tumors and lymph node metastasis status were the only significant (P<0.05) parameters for detecting liver metastasis. The predictive accuracy of markers was assessed by the cross-validation method and an independent test set. In leave-one-out cross-validation, the two markers combined with clinicopathologic features resulted in 91.2% sensitivity and 96.4% specificity for hepatic metastasis detection. In an independent test set, the combination achieved 94.5% sensitivity and 88.9% specificity for predicting the hepatic metastasis of colorectal cancer.
Our results suggest that combined HP and OPN expression levels are significantly related to liver metastasis and prognosis, and, if this is validated, they could be used as accurate predictors of liver metastasis in colorectal cancer.
Annals of Surgical Oncology 01/2012; 19(7):2411-9. · 4.12 Impact Factor
[show abstract][hide abstract] ABSTRACT: P-cadherin belongs to the family of classic cadherins, which is important for maintaining cellular localization and tissue integrity. Recently, it has become evident that P-cadherin contributes to the oncogenesis of many tumor types, including melanoma, prostate, breast, and colon carcinomas. Although cadherin switching is a crucial step in metastasis, the role of P-cadherin in colon cancer metastasis to the liver is unknown. In this study, we performed gene expression analysis and found that the level of P-cadherin was higher in tissue from liver metastases of colon cancer than in the corresponding primary colon cancer tissues. IHC analysis also showed that P-cadherin expression was significantly higher in liver metastases than in paired primary colorectal cancer tumors. Knockdown of P-cadherin in colon cancer cells inhibited wound healing, proliferation, and colony formation and resulted in developing fewer liver metastatic foci and reducing the tumor burden in vivo. Inhibition of P-cadherin expression also induced the up-regulation of E-cadherin and the down-regulation of β-catenin and its downstream target molecules, including survivin and c-Myc. In summary, these results uncover a novel function of P-cadherin in the regulation of colon cancer metastasis to the liver, suggesting that blocking the activity of P-cadherin or its associated signaling may be a valuable target for the treatment of hepatic metastases of colon carcinomas.
American Journal Of Pathology 07/2011; 179(1):380-90. · 4.52 Impact Factor
[show abstract][hide abstract] ABSTRACT: Increasing evidence suggests that microRNAs are involved in human carcinogenesis as tumor suppressors or oncogenes. A growing number of reports has shown that an interest has been sparked in aberrant microRNA expression and how they can be used to treat human diseases, including cancer. However, their precise biological role remains largely unknown. In the present study, we aimed to identify micro-RNA species involved in the regulation of tumor growth. By performing quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis, we demonstrated that mir-663 was downregulated in human gastric cancer cell lines unlike in normal cells. A transient introduction of mir-663 into the human gastric cancer cell lines BGC823 and SNU5 induced morphology changes and suppression of proliferation of these cells. In addition, mir-663 alters the DNA content and induces phenotypes of mitotic catastrophe in tumor cells. Moreover, the liposome-mediated delivery of mir-663 suppressed the in vivo growth of the BGC823 and SNU5 cells. Western blot analyses performed after the introduction of mir-663 revealed upregulation of cyclin B following transfection with mir-663. Our results provide evidence that downregulation of mir-663 in tumor cells may contribute to aberrant cell hyperplasia, leading to the development of gastric cancer. Therefore, mir-663 might function as a potent suppressor of tumor growth.
[show abstract][hide abstract] ABSTRACT: This study aimed to identify novel biological markers for the prediction of colorectal cancer liver metastasis.
We established two models that mimicked the interactions between colorectal tumor cells and the liver microenvironment. From these models we established subcell lines that had an enhanced ability to metastasize to the liver. Genes that related to hepatic metastasis were screened by microarray. The candidate markers were tested by immunohistochemistry, and their predictive accuracy was assessed by the cross-validation method and an independent test set.
Highly metastatic colon cancer cell sublines SW1116p21 and SW1116v3 were established from the tumor cell-microenvironment interaction models. Seven of the up-regulated genes in the sublines were selected as candidate markers for predicting metastatic potential. A total of 245 colorectal cancer samples were divided into a training set containing 117 cases and a test set containing 128 cases. In the training set, immunohistochemical analysis showed CCL2 and SNCG expression was higher in the hepatic metastasis group than in the nonmetastasis group, and was correlated with poor survival. Logistic regression analysis revealed that CCL2 and SNCG levels in primary tumors, serum carcinoembryonic antigen level, and lymph node metastasis status were the only significant (P < 0.05) parameters for detecting liver metastasis. In leave-one-out-cross-validation, the two markers, when combined with clinicopathologic features, resulted in 90.5% sensitivity and 90.7% specificity for hepatic metastasis detection. In an independent test set, the combination achieved 87.5% sensitivity and 82% specificity for predicting the future hepatic metastasis of colorectal cancer.
Our results suggest that these models are able to mimic the interactions between colorectal cancer cells and the liver microenvironment, and may represent a promising strategy to identify metastasis-related genes. CCL2 and SNCG, combined with clinicopathologic features, may be used as accurate predictors of liver metastasis in colorectal cancer.
Clinical Cancer Research 08/2009; 15(17):5485-93. · 7.84 Impact Factor
[show abstract][hide abstract] ABSTRACT: Esophageal cancer is characterized by rapid clinical progression and poor prognosis, due to early-stage invasion of adjacent tissues and metastasis. Tissue factor pathway inhibitor-2 (TFPI-2) has been implicated as a metastasis-associated gene in many types of tumors. Here we describe the potential involvement of TFPI-2 in the development of esophageal carcinoma. Western blotting revealed that TFPI-2 was downregulated in 75% of esophageal carcinomas and in most esophageal carcinoma cell lines. Immunohistochemistry revealed that TFPI-2 was significantly downregulated in tumor tissues and in lymph node metastases. Experimental overexpression of TFPI-2 in KYSE450, KYSE510, YES2, and EC9706 cells significantly inhibited their invasive ability. Overexpression of TFPI-2 in EC9706 cells inhibited xenograft tumor growth and invasion into surrounding tissues, as well as reduced lung metastasis. Further studies demonstrated that recombinant TFPI-2 protein significantly inhibited the activity of matrix metalloproteinases and tumor-related angiogenesis. Parenteral treatment with recombinant TFPI-2 protein significantly suppressed xenograft growth and metastasis. Together, these data indicate that TFPI-2 inhibits tumor invasion and angiogenesis both in vitro and in vivo, and suggest a potentially important therapeutic role for recombinant TFPI-2 in the treatment of malignant esophageal carcinomas.
Human gene therapy 01/2009; 20(1):41-9. · 4.20 Impact Factor