Liyan Xue

Barts Cancer Institute, London, ENG, United Kingdom

Are you Liyan Xue?

Claim your profile

Publications (21)93.08 Total impact

  • Source
    Dataset: Accumulation of cytoplasmic β-catenin correlates with reduced expression of E-cadherin, but not with phosphorylated Akt in esophageal squamous cell carcinoma; Immunohistochemical study Corrigendum
  • Article: Pulmonary metastasis of a papillary thyroid carcinoma and primary lung adenocarcinoma: two coincident carcinomas at the same location.
    [show abstract] [hide abstract]
    ABSTRACT: Tumor-to-tumor metastasis is a fairly rare phenomenon. The lung cancers are the most common donors, but are exceedingly rare as recipients. Here we report a case of a lung adenocarcinoma acting as the recipient of papillary thyroid carcinoma, with multiple spreading foci of the two cancers in the lung simultaneously. The morphology and immunohistochemisty (Napsin-A, Thyroglobulin) are very important in differential diagnosis of lung primary adenocarcinoma and metastatic papillary thyroid carcinoma. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2069496615891134.
    Diagnostic Pathology 02/2013; 8(1):26. · 1.64 Impact Factor
  • Article: Parameters predicting lymph node metastasis in patients with superficial esophageal squamous cell carcinoma.
    [show abstract] [hide abstract]
    ABSTRACT: Endoscopic resection is a less invasive treatment than esophagectomy for superficial esophageal squamous cell carcinoma, but patients with lymph node metastasis need additional treatment after endoscopic resection. The purpose of this study was to establish a set of indicators to identify superficial esophageal squamous cell carcinoma patients at a high risk of metastasis. In all, 271 superficial esophageal squamous cell carcinoma esophagectomy cases were reviewed retrospectively. The relationships between clinicopathological parameters and immunohistochemical findings (p53, cyclin D1, EGFR and VEGF) on tissue microarrays, on the one hand, and lymph node metastasis were assessed by univariate and multivariate logistic regression analyses. Patients with intraluminal masses and ulcerated masses had a high risk of lymph node metastasis. Patients with superficial esophageal squamous cell carcinoma (1) thinner than 1200 μm; (2) confined to the mucosa; (3) with submucosal invasion <250 μm; (4) with submucosal invasion ≥250 μm but with negative VEGF expression and well/moderately differentiated or basaloid histology; or (5) with submucosal invasion ≥250 μm but with weak VEGF expression and well-differentiated histology had almost no risk of lymph node metastasis. We recommend endoscopic resection for all erosive, papillary and plaque-like superficial esophageal squamous cell carcinomas where endoscopic resection is clinically feasible, and esophagectomy for all other erosive, papillary and plaque-like cases and all intraluminal masses and ulcerated tumors. No additional treatment is needed for endoscopic resection cases with superficial esophageal squamous cell carcinoma (1) thinner than 1200 μm; (2) confined to the mucosa; (3) with submucosal invasion <250 μm; (4) with submucosal invasion ≥250 μm but with negative VEGF expression and well/moderately differentiated or basaloid histology; or (5) with submucosal invasion ≥250 μm but with weak VEGF expression and well-differentiated histology. These clinical and pathological criteria should enable more accurate selection of patients for these procedures.
    Modern Pathology 05/2012; 25(10):1364-77. · 4.79 Impact Factor
  • Article: High-resolution genome-wide copy-number analysis suggests a monoclonal origin of multifocal prostate cancer.
    [show abstract] [hide abstract]
    ABSTRACT: Many human cancers present as multifocal lesions. Understanding the clonal origin of multifocal cancers is of both etiological and clinical importance. The molecular basis of multifocal prostate cancer has previously been explored using a limited number of isolated markers and, although independent origin is widely believed, the clonal origin of multifocal prostate cancer is still debatable. We attempted to address clonal origin using a genome-wide copy-number analysis of individual cancer and high-grade prostatic intraepithelial neoplasia (HGPIN) lesions. Using Affymetrix array 6.0 copy-number analysis, we compared the genomic changes detected in 48 individual cancer and HGPIN lesions, isolated from 18 clinically localized prostate cancer cases. Identical genomic copy-number changes, shared by all same-case cancer foci, were detected in all 13 informative cases displaying multiple tumor foci. In addition, individual HGPIN lesions in the two multifocal-HGPIN cases available shared identical genomic changes. Commonly known genomic alterations, including losses at 6q15, 8p21.3-8p21.2, 10q23.2-10q23.31, 16q22.3, 16q23.2-16q23.3 and 21q22.2-21q22.3 regions and gain of 8q24.3 were the most frequently detected changes in this study and each was detected in all same-case foci in at least one case. Microarray data were confirmed by fluorescence in situ hybridization in selected foci. Our high-resolution genome-wide copy-number data suggest that many multifocal cases derive from a single prostate cancer precursor clone and that this precursor may give rise to separate HGPIN foci and may further progress to multifocal invasive prostate cancer. These findings, which demonstrate the monoclonal origin of multifocal prostate cancer, should significantly enhance our understanding of prostate carcinogenesis.
    Genes Chromosomes and Cancer 02/2012; 51(6):579-89. · 3.31 Impact Factor
  • Source
    Article: Genome-wide screening for genetic alterations in esophageal cancer by aCGH identifies 11q13 amplification oncogenes associated with nodal metastasis.
    [show abstract] [hide abstract]
    ABSTRACT: Esophageal squamous cell carcinoma (ESCC) is highly prevalent in China and other Asian countries, as a major cause of cancer-related mortality. ESCC displays complex chromosomal abnormalities, including multiple structural and numerical aberrations. Chromosomal abnormalities, such as recurrent amplifications and homozygous deletions, directly contribute to tumorigenesis through altering the expression of key oncogenes and tumor suppressor genes. To understand the role of genetic alterations in ESCC pathogenesis and identify critical amplification/deletion targets, we performed genome-wide 1-Mb array comparative genomic hybridization (aCGH) analysis for 10 commonly used ESCC cell lines. Recurrent chromosomal gains were frequently detected on 3q26-27, 5p15-14, 8p12, 8p22-24, 11q13, 13q21-31, 18p11 and 20q11-13, with frequent losses also found on 8p23-22, 11q22, 14q32 and 18q11-23. Gain of 11q13.3-13.4 was the most frequent alteration in ESCC. Within this region, CCND1 oncogene was identified with high level of amplification and overexpression in ESCC, while FGF19 and SHANK2 was also remarkably over-expressed. Moreover, a high concordance (91.5%) of gene amplification and protein overexpression of CCND1 was observed in primary ESCC tumors. CCND1 amplification/overexpression was also significantly correlated with the lymph node metastasis of ESCC. These findings suggest that genomic gain of 11q13 is the major mechanism contributing to the amplification. Novel oncogenes identified within the 11q13 amplicon including FGF19 and SHANK2 may play important roles in ESCC tumorigenesis.
    PLoS ONE 01/2012; 7(6):e39797. · 4.09 Impact Factor
  • Source
    Article: Overexpression of the DEC1 protein induces senescence in vitro and is related to better survival in esophageal squamous cell carcinoma.
    [show abstract] [hide abstract]
    ABSTRACT: Esophageal squamous cell carcinoma (ESCC) is a leading cause of cancer-related death in China and has limited effective therapeutic options except for early surgery, since the underlying molecular mechanism driving its precursor lesions towards invasive ESCC is not fully understood. Cellular senescence is the state of the permanent growth arrest of a cell, and is considered as the initial barrier of tumor development. Human differentiated embryo chondrocyte expressed gene 1 (Dec1) is an important transcription factor that related to senescence. In this study, DEC1 immunohistochemical analysis was performed on tissue microarray blocks constructed from ESCC combined with adjacent precursor tissues of 241 patients. Compared with normal epithelia, DEC1 expression was significantly increased in intraepithelial neoplasia and DEC1 expression was significantly decreased in ESCC in comparison with intraepithelial neoplasia. In vitro, DEC1 overexpression induced cellular senescence, and it inhibited cell growth and colony formation in ESCC cell line EC9706. Fresh esophagectomy tissue sections from five ESCC patients were detected by immunohistochemistry of DEC1 and senescence-associated β-galactosidase (SA-β-Gal) activity, and strongly positive expression of DEC1 was correlated to more senescent cells in these fresh tissue sections. Kaplan-Meier method analysis of the 241 patients revealed that DEC1 expression levels were significantly correlated with the survival of ESCC patients after surgery. The expression levels of DEC1 were also correlated with age, tumor embolus, depth of invasion of ESCC, lymph metastasis status and pTNMs. These results suggest that DEC1 overexpression in precursor lesions of ESCC is a protective mechanism by inducing cellular senescence in ESCC initiation, and DEC1 may be a potential prognostic marker of ESCC.
    PLoS ONE 01/2012; 7(7):e41862. · 4.09 Impact Factor
  • Article: Chinese and Western prostate cancers show alternate pathogenetic pathways in association with ERG status.
    [show abstract] [hide abstract]
    ABSTRACT: We have previously reported genetic differences between Western and Chinese prostate cancers, including different frequencies of ERG rearrangements. We investigated further ERG expression and rearrangements in prostate cancers and high-grade prostatic intraepithelial neoplasia (HGPIN) from the UK and China to determine differences between these two populations by tissue microarray based immunohistochemistry and fluorescence in situ hybridization. In keeping with our previous observation, that ERG was rearranged at a higher frequency in UK prostate cancer samples (38%, 58/155) than Chinese ones (8%, 7/93), ERG rearrangements were also found in 21% (4/19) and 0% (0/19) foci of HGPIN in UK and Chinese samples respectively. ERG nuclear expression in UK cancers (34%, 54/160) was significantly higher than that in Chinese ones (10%, 9/88) (p<0.001). ERG nuclear expression in UK HGPIN (28%, 11/39) was higher than that in Chinese HGPIN (0%, 0/9), but without statistical significance (p=0.193). ERG nuclear expression was correlated to ERG rearrangements in both UK (Kappa=0.686) and Chinese (Kappa=0.565) cancers. These data demonstrate that ERG rearrangement and expression frequencies are different in prostate cancers from UK and China as early as the precursor lesion, HGPIN. The nuclear expression is associated with ERG rearrangements which mainly occur in the Western samples. UK and Chinese prostate cancers may be the result of different genetic mechanisms.
    American journal of cancer research. 01/2012; 2(6):736-44.
  • Article: Outcomes from a prospective trial of endoscopic radiofrequency ablation of early squamous cell neoplasia of the esophagus.
    [show abstract] [hide abstract]
    ABSTRACT: Radiofrequency ablation (RFA) is safe and effective for eradicating neoplasia in Barrett's esophagus. To evaluate RFA for eradicating early esophageal squamous cell neoplasia (ESCN) defined as moderate-grade squamous intraepithelial neoplasia (MGIN) and high-grade squamous intraepithelial neoplasia (HGIN) and early flat-type esophageal squamous cell carcinoma (ESCC). Prospective cohort study. Tertiary referral center. Esophageal unstained lesions (USLs) were identified using Lugol's chromoendoscopy. Inclusion criteria were at least 1 flat (type 0-IIb) USL 3 cm or larger, USL-bearing esophagus 12 cm or less, and a consensus diagnosis of MGIN, HGIN, or ESCC by 2 expert GI pathologists. Exclusion criteria were previous endoscopic resection or ablation, stricture, or any nonflat mucosa. Circumferential RFA creating a continuous treatment area (TA) including all USLs. At 3-month intervals thereafter, chromoendoscopy with biopsies followed by focal RFA of USLs, if present. Complete response (CR) at 12 months defined as absence of MGIN, HGIN, or ESCC in the TA, CR after 1 RFA session, neoplastic progression from baseline, and adverse events. Twenty-nine patients (14 male, mean age 60.3 years) with MGIN (n = 18), HGIN (n = 10), or ESCC (n = 1) participated. Mean USL length was 6.2 cm (TA 8.2 cm). At 3 months after 1 RFA session, 86% of patients (25/29) had a CR. At 12 months, 97% of patients (28/29) had a CR. There was no neoplastic progression. There were 4 strictures, all dilated to resolution. Single-center study with limited number of patients. In patients with early ESCN (MGIN, HGIN, flat-type ESCC), RFA was associated with a high rate of histological complete response (97% of patients), no neoplastic progression, and an acceptable adverse event profile.
    Gastrointestinal endoscopy 08/2011; 74(6):1181-90. · 6.71 Impact Factor
  • Article: Chromosome rearrangement associated inactivation of tumour suppressor genes in prostate cancer.
    [show abstract] [hide abstract]
    ABSTRACT: Prostate cancer, the most common male cancer in Western countries, is commonly detected with complex chromosomal rearrangements. Following the discovery of the recurrent TMPRSS2:ETS fusions in prostate cancer and EML4:ALK in non-small-cell lung cancer, it is now accepted that fusion genes not only are the hallmark of haematological malignancies and sarcomas, but also play an important role in epithelial cell carcinogenesis. However, previous studies aiming to identify fusion genes in prostate cancer were mainly focused on expression changes and fusion transcripts. To investigate the genes recurrently affected by the chromosome breakpoints in prostate cancer, we analysed Affymetrix array 6.0 and 500K SNP microarray data from 77 prostate cancer samples. While the two genes most frequently affected by genomic breakpoints were, as expected, ERG and TMPRSS2, surprisingly more known tumour suppressor genes (TSGs) than known oncogenes were identified at recurrent chromosome breakpoints. Certain well-characterised TSGs, including p53, PTEN, BRCA1 and BRCA2 are recurrently truncated as a result of chromosome rearrangements in prostate cancer. Interestingly, many of the genes residing at recurrent breakpoint sites have not yet been implicated in prostate carcinogenesis such as HOOK3, PPP2R2A and TCBA1. We have confirmed the generally reduced expression of selected genes in clinical samples using quantitative RT-PCR analysis. Subsequently, we further investigated the genes associated with the t(4:6) translocation in LNCaP cells and reveal the genomic fusion of SNX9 and putative TSG UNC5C, which led to the reduced expression of both genes. This study reveals another common mechanism that leads to the inactivation of TSGs in prostate cancer and the identification of multiple TSGs inactivated by chromosome rearrangements will lead to new direction of research for the molecular basis of prostate carcinogenesis.
    American journal of cancer research. 01/2011; 1(5):604-17.
  • Article: Absolute quantitation of DNA methylation of 28 candidate genes in prostate cancer using pyrosequencing.
    [show abstract] [hide abstract]
    ABSTRACT: Aberrant DNA methylation plays a pivotal role in carcinogenesis and its mapping is likely to provide biomarkers for improved diagnostic and risk assessment in prostate cancer (PCa). We quantified and compared absolute methylation levels among 28 candidate genes in 48 PCa and 29 benign prostate hyperplasia (BPH) samples using the pyrosequencing (PSQ) method to identify genes with diagnostic and prognostic potential. RARB, HIN1, BCL2, GSTP1, CCND2, EGFR5, APC, RASSF1A, MDR1, NKX2-5, CDH13, DPYS, PTGS2, EDNRB, MAL, PDLIM4, HLAa, ESR1 and TIG1 were highly methylated in PCa compared to BPH (p < 0.001), while SERPINB5, CDH1, TWIST1, DAPK1, THRB, MCAM, SLIT2, CDKN2a and SFN were not. RARB methylation above 21% completely distinguished PCa Separation based on methylation level of SFN, SLIT2 and SERPINB5 distinguished low and high Gleason score cancers, e.g. SFN and SERPINB5 together correctly classified 81% and 77% of high and low Gleason score cancers respectively. Several genes including CDH1 previously reported as methylation markers in PCa were not confirmed in our study. Increasing age was positively associated with gene methylation (p < 0.0001).Accurate quantitative measurement of gene methylation in PCa appears promising and further validation of genes like RARB, HIN1, BCL2, APC and GSTP1 is warranted for diagnostic potential and SFN, SLIT2 and SERPINB5 for prognostic potential.
    Disease markers 01/2011; 30(4):151-61. · 1.64 Impact Factor
  • Article: Distinct genomic alterations in prostate cancers in Chinese and Western populations suggest alternative pathways of prostate carcinogenesis.
    [show abstract] [hide abstract]
    ABSTRACT: Prostate cancer is significantly more common in Western men than in Asian men, but the basis for this difference remains unknown. Because genomic studies of Asian prostate cancer are very limited, we used a genome-wide approach to reveal the genomic alterations in Chinese prostate cancers. We found a significant reduction in the frequency of certain somatic genomic changes that are commonly found in Western prostate cancers, including the 21q22.2-22.3 deletion, which involves the TMPRSS2:ERG fusion gene, and 10q deletion, which causes PTEN inactivation. Array results were confirmed by PCR-based molecular copy-number counting in selected samples. The different frequencies of these genomic changes were further evaluated by fluorescent in situ hybridization and immunohistochemistry analyses of tissue microarray samples. These alterations might be key genetic changes underlying the regional/ethnic difference in clinical incidence and might be induced by specific environmental and/or genetic risk factors that Western men are exposed to. Our findings suggest that tumors arise in Western and Chinese populations by alternative pathogenetic mechanisms.
    Cancer Research 07/2010; 70(13):5207-12. · 7.86 Impact Factor
  • Article: The association of CCND1 overexpression and cisplatin resistance in testicular germ cell tumors and other cancers.
    [show abstract] [hide abstract]
    ABSTRACT: Development of chemoresistance limits the clinical efficiency of platinum-based therapy. Although many resistance mechanisms have been demonstrated, genetic/molecular alterations responsible for drug resistance in the majority of clinical cases have not been identified. We analyzed three pairs of testicular germ cell tumor cell lines using Affymetrix expression microarrays and revealed a limited number of differentially expressed genes across the cell lines when comparing the parental and resistant cells. Among them, CCND1 was the most significantly differentially expressed gene. Analysis of testicular germ cell tumor clinical samples by quantitative reverse transcription PCR analysis revealed that overall expression of CCND1 was significantly higher in resistant cases compared with sensitive samples (P < 0.0001). We also found that CCND1 was dramatically overexpressed both in induced and intrinsically resistant samples of ovarian and prostate cancer. Finally combined CCND1 knockdown using small-interfering RNA and cisplatin treatment inhibited cell growth in vitro significantly more effectively than any of these single treatments. Therefore, deregulation of CCND1 may be a major cause of cisplatin resistance in testicular germ cell tumors and may also be implicated in ovarian and prostate cancers. CCND1 could be potentially used as a marker for treatment stratification and as a molecular target to improve the treatment of platinum-resistant tumors.
    American Journal Of Pathology 06/2010; 176(6):2607-15. · 4.89 Impact Factor
  • Article: Centrosomal Nlp is an oncogenic protein that is gene-amplified in human tumors and causes spontaneous tumorigenesis in transgenic mice.
    [show abstract] [hide abstract]
    ABSTRACT: Disruption of mitotic events contributes greatly to genomic instability and results in mutator phenotypes. Indeed, abnormalities of mitotic components are closely associated with malignant transformation and tumorigenesis. Here we show that ninein-like protein (Nlp), a recently identified BRCA1-associated centrosomal protein involved in microtubule nucleation and spindle formation, is an oncogenic protein. Nlp was found to be overexpressed in approximately 80% of human breast and lung carcinomas analyzed. In human lung cancers, this deregulated expression was associated with NLP gene amplification. Further analysis revealed that Nlp exhibited strong oncogenic properties; for example, it conferred to NIH3T3 rodent fibroblasts the capacity for anchorage-independent growth in vitro and tumor formation in nude mice. Consistent with these data, transgenic mice overexpressing Nlp displayed spontaneous tumorigenesis in the breast, ovary, and testicle within 60 weeks. In addition, Nlp overexpression induced more rapid onset of radiation-induced lymphoma. Furthermore, mouse embryonic fibroblasts (MEFs) derived from Nlp transgenic mice showed centrosome amplification, suggesting that Nlp overexpression mimics BRCA1 loss. These findings demonstrate that Nlp abnormalities may contribute to genomic instability and tumorigenesis and suggest that Nlp might serve as a potential biomarker for clinical diagnosis and therapeutic target.
    The Journal of clinical investigation 02/2010; 120(2):498-507. · 15.39 Impact Factor
  • Article: Aurora-A interacts with Cyclin B1 and enhances its stability.
    [show abstract] [hide abstract]
    ABSTRACT: The mitotic regulator Aurora-A is an oncogenic protein that is over-expressed in many types of human tumors. However, the underlying mechanism through which Aurora-A promotes tumorigenesis remains unclear. Here, we show that overexpression of Aurora-A causes an elevation of Cyclin B1 expression. Cyclin B1 degradation is delayed in Aurora-A over-expressing cells, which depends on Aurora-A kinase activity. In contrast, Aurora-A RNAi enhances Cyclin B1 degradation. Furthermore, we found that Aurora-A interacts with Cyclin B1, and that Aurora-A overexpression reduces the interaction of Cyclin B1 with APC subunits. In human esophageal squamous cell carcinomas (ESCC), overexpression of Aurora-A was correlated with deregulated expression of Cyclin B1. Taken together, these findings suggest that overexpression of Aurora-A may stabilize Cyclin B1 through inhibiting its degradation. These results provide new insight into the mechanism of how deregulated Aurora-A contributes to genomic instability and carcinogenesis.
    Cancer letters 12/2008; 275(1):77-85. · 4.86 Impact Factor
  • Article: FRAT1 overexpression leads to aberrant activation of beta-catenin/TCF pathway in esophageal squamous cell carcinoma.
    [show abstract] [hide abstract]
    ABSTRACT: Esophageal squamous cell carcinoma (ESCC) is an aggressive tumor with a poor prognosis. Although aberrant activation of beta-catenin/T-cell factor (TCF) pathway has been observed in ESCC, mechanisms underlying this phenomenon remain unknown. Frequently rearranged in advanced T-cell lymphomas-1 (FRAT1), overexpressed in some ESCC lines, is a positive regulator of beta-catenin/TCF pathway. However, little is known about the molecular relationship between FRAT1 and beta-catenin/TCF in ESCC. In this study, we analyzed freshly resected ESCC specimens and demonstrated that FRAT1 was overexpressed in approximately 74% of tumor samples compared with matched normal tissue. Overexpression of FRAT1 significantly promoted esophageal cancer cells growth, whereas suppression of FRAT1 level by RNAi markedly inhibited their growth. In addition, FRAT1 overexpression induced the nuclear accumulation of beta-catenin and promoted the transcriptional activity of beta-catenin/TCF. These effects were reversed by coexpression of GSK 3beta or DeltaN TCF4. Furthermore, accumulation of beta-catenin was correlated with FRAT1 overexpression in ESCC and the basal layer of normal esophageal epithelium. Finally, continued expression of c-Myc is necessary and sufficient for maintenance of the growth state in cells expressing FRAT1. Taken together, these results support the novel hypothesis that aberrant activation of beta-catenin/TCF pathway in esophageal cancer appears to be due to upstream events such as FRAT1 overexpression, and c-Myc may be an important element in oncogenesis of human ESCC induced by FRAT1.
    International Journal of Cancer 09/2008; 123(3):561-8. · 5.44 Impact Factor
  • Article: Overexpression of cyclin B1 in human esophageal squamous cell carcinoma cells induces tumor cell invasive growth and metastasis.
    [show abstract] [hide abstract]
    ABSTRACT: Cyclin B1, a key component in the control of cell cycle progression from G(2) to M phase, has been implicated in tumorigenesis and the development of malignancy. However, the underlying mechanism by which cyclin B1 acts as an important oncogenic molecule remains largely unknown. Here we show that ectopic expression of cyclin B1 promotes cell proliferation, enhances cell motility and migration and results in increased ability of cells extravasating through the capillary endothelium. Interestingly, isogenic esophageal squamous cell carcinoma (ESCC) cells overexpressing cyclin B1 reveal strong invasive growth and high potential of metastasis to lung in xenograft mice. Suppression of cyclin B1 expression via small interfering RNA approach in high-metastatic esophagus carcinoma cells specifically inhibits their ability to metastasize from the primary ESCC to lung. Notably, altered expression of epithelial markers and mesenchymal markers were observed in the cells overexpressing cyclin B1, suggesting that cyclin B1 contributes to metastasis probably by promoting an epithelial-mesenchymal transition. These results establish a mechanistic link between cyclin B1 and ESCC metastasis and provide novel insight into understanding of cyclin B1 in the development of ESCC malignancy.
    Carcinogenesis 03/2008; 29(2):307-15. · 5.70 Impact Factor
  • Article: Functional polymorphisms in FAS and FASL contribute to increased apoptosis of tumor infiltration lymphocytes and risk of breast cancer.
    [show abstract] [hide abstract]
    ABSTRACT: The FAS-FASL system plays crucial role in counterattack of cancer cell against immune system. This study examined the effects of FAS (-1377G/A and -670A/G) and FASL (-844T/C and 7896G/C) polymorphisms on breast cancer risk and apoptosis of T lymphocytes. The effect on breast cancer risk was determined by case-control analysis of 840 patients and 840 controls. The effects on T-lymphocyte apoptosis were determined by activation-induced cell death (AICD) of T cells ex vivo and by analyzing apoptotic tumor-infiltrating lymphocytes (TILs) in breast cancer tissue. We found moderately increased risk associated with FAS -1377AG [odds ratio (OR), 1.29; 95% confidence interval (CI), 1.05-1.59] and -1377AA (OR, 1.36; 95% CI, 1.01-1.82) genotypes compared with the -1377GG genotype and decreased risk associated with FASL -844CT (OR, 0.76; 95% CI, 0.62-0.94) and -844TT (OR, 0.66; 95% CI, 0.43-1.00) genotypes compared with the -844CC genotype. T lymphocytes with the FASL -844CC genotype had heightened FASL expression that is associated with increased AICD of the T cells stimulated by MCF-7 cells or phytohemagglutinin compared with the FASL -844TT genotype (10.38 +/- 4.09% and 24.29 +/- 1.50% versus 6.03 +/- 0.41% and 17.96 +/- 3.66%; P < 0.05 and 0.001). Breast cancer patients with the FASL -844CC genotype had higher apoptotic TILs in their cancer tissues than those with the FASL -844TT genotype (33.7 +/- 1.2% versus 19.1 +/- 2.0%; P = 0.007). These findings indicate that functional polymorphisms in FAS and FASL contribute to increased apoptosis of tumor infiltration lymphocytes and risk of breast cancer.
    Carcinogenesis 05/2007; 28(5):1067-73. · 5.70 Impact Factor
  • Article: Overexpression of EB1 in human esophageal squamous cell carcinoma (ESCC) may promote cellular growth by activating beta-catenin/TCF pathway.
    [show abstract] [hide abstract]
    ABSTRACT: Esophageal squamous cell carcinoma (ESCC) has a multifactorial etiology involving environmental and/or genetic factors. End-binding protein 1 (EB1), which was cloned as an interacting partner of the adenomatous polyposis coli (APC) tumor suppressor protein, was previously found overexpressed in ESCC. However, the precise role of EB1 in the development of this malignancy has not yet been elucidated. In this study, we analysed freshly resected ESCC specimens and demonstrated that EB1 was overexpressed in approximately 63% of tumor samples compared to matched normal tissue. We report that overexpression of EB1 in the ESCC line EC9706 significantly promotes cell growth, whereas suppression of EB1 protein level by RNA interference significantly inhibited growth of esophageal tumor cells. In addition, EB1 overexpression induced nuclear accumulation of beta-catenin and promoted the transcriptional activity of beta-catenin/T-cell factor (TCF). These effects were partially or completely abolished by coexpression of APC or DeltaN TCF4, respectively. Also, we found that EB1 affected the interaction between beta-catenin and APC. Furthermore, EB1 overexpression was correlated with cytoplasmic/nuclear accumulation of beta-catenin in primary human ESCC. Taken together, these results support the novel hypothesis that EB1 overexpression may play a role in the development of ESCC by affecting APC function and activating the beta-catenin/TCF pathway.
    Oncogene 11/2005; 24(44):6637-45. · 6.37 Impact Factor
  • Source
    Article: Accumulation of cytoplasmic beta-catenin correlates with reduced expression of E-cadherin, but not with phosphorylated Akt in esophageal squamous cell carcinoma: immunohistochemical study.
    [show abstract] [hide abstract]
    ABSTRACT: Accumulation of beta-catenin in cytoplasm occurs frequently during the pathogenesis of esophageal squamous cell carcinoma (ESCC). The mechanism leading to this alteration, however, is largely unknown. In the present study, immunohistochemistry was performed for beta-catenin, E-cadherin and Ser473 phosphorylated Akt (P-Akt) in 44 tissue samples of ESCC and corresponding normal esophageal epithelium. Exon 3 of the beta-catenin gene was analyzed by using single-strand conformation polymorphism and direct sequencing. In addition to the reduced expression of E-cadherin and membranous beta-catenin observed in 65.9% and 68% of ESCC tested, respectively, cytoplasmic accumulation of beta-catenin was also detected in 68% (30/44) cases. However, only two cases were found to have the same beta-catenin gene mutation. The data showed that cytoplasmic accumulation of beta-catenin was significantly associated with reduced expression of E-cadherin (P < 0.05) and that of membranous beta-catenin (P < 0.05). Furthermore, cytoplasmic beta-catenin was correlated significantly with lymph node metastasis (P < 0.05). In contrast, although strong staining of P-Akt occurred in 14 of 44 cases (32%), there was no significant correlation between the positive staining of P-Akt and cytoplasmic beta-catenin. Taken together these results suggest that the lost membranous beta-catenin might translocate to cytoplasm depending on reduced expression of E-cadherin, while Akt seems unlikely to play a role in this process.
    Pathology International 06/2005; 55(6):310-7. · 1.62 Impact Factor
  • Article: Overexpression of human pituitary tumor transforming gene (hPTTG), is regulated by beta-catenin /TCF pathway in human esophageal squamous cell carcinoma.
    [show abstract] [hide abstract]
    ABSTRACT: Overexpression of human pituitary tumor transforming gene (PTTG) is wildly detected in many tumors, including esophageal cancer. Besides overexpression of PTTG in esophageal squamous cell carcinoma (ESCC) tissues and cells, we detected accumulation of cytoplasmic beta-catenin in ESCC. In our study, a putative TCF4-binding element (TBE) was identified in PTTG promoter region. The activity of PTTG promoter containing the TBE was activated by S37Abeta-catenin and inhibited by dominant-negative TCF. Furthermore, the activation by S37Abeta-catenin was mostly abrogated among PTTG promoter region without the TBE or with a mutant one. By using biotin-streptavidin pull-down assay, we also found that the TBE among PTTG promoter bound to TCF-4 protein. Moreover, levels of PTTG mRNA and protein were increased by S37Abeta-catenin. Finally, it is noticeable that we detected a correlation between beta-catenin localization and PTTG expression in 69 primary ESCC (p<0.01). In brief, our study shows that overexpression of PTTG in ESCC is likely due to the activation of beta-catenin/WNT signaling. As a target gene of beta-catenin/TCF pathway, PTTG may play an important role in tumorigenesis of human ESCC.
    International Journal of Cancer 04/2005; 113(6):891-8. · 5.44 Impact Factor

Institutions

  • 2012
    • Barts Cancer Institute
      London, ENG, United Kingdom
  • 2010–2012
    • Queen Mary, University of London
      • Centre for Molecular Oncology
      London, ENG, United Kingdom
    • University of London
      London, ENG, United Kingdom
  • 2005–2010
    • Peking Union Medical College Hospital
      Beijing, Beijing Shi, China