Hai Xia Deng

EZH2 supports ovarian carcinoma cell invasion and/or metastasis via regulation of TGF-β1 and is a predictor of outcome in ovarian carcinoma patients

It was suggested that the enhancer of zeste homolog 2 (EZH2) gene is a putative candidate oncogene in several types of human cancer. The potential oncogenic role of EZH2 and its clinical/prognostic significance, however, in ovarian carcinoma are unclear. In this study, EZH2 expression was examined by immunohistochemistry (IHC) in cohorts of normal and tumorous ovarian tissues. High expression of EZH2 was examined in none of the normal ovaries, in 3% of the cystadenomas, in 23% of the borderline tumors and in 50% of the ovarian carcinomas, respectively. In the ovarian carcinomas, high expression of EZH2 was positively correlated with an ascending histological grade and/or advanced stage of the disease (P < 0.05). Moreover, high expression of EZH2 in ovarian carcinoma was determined to be a strong and an independent predictor of short overall survival (P < 0.05). In ovarian carcinoma HO-8910 and UACC-326 cell lines, EZH2 knockdown by RNA interference led to a G(1) phase cell cycle arrest, reduced cell growth/proliferation and inhibited cell migration and/or invasion in vitro. In addition, EZH2 knockdown was found to reduce transforming growth factor-beta1 (TGF-beta1) expression and increase E-cadherin expression either in the transcript or in the protein levels. Furthermore, a significant positive correlation between overexpression of EZH2 and TGF-beta1 in ovarian carcinoma tissues was observed (P < 0.001). These findings suggest a potential important role of EZH2 in the control of cell migration and/or invasion via the regulation of TGF-beta1 expression, and the high expression of EZH2, as detected by IHC, is an independent molecular marker for shortened survival time of patients with ovarian carcinoma.

MicroRNA-29c enhances the sensitivities of human nasopharyngeal carcinoma to cisplatin-based chemotherapy and radiotherapy

This study was aimed to investigate the potential role of microRNA-29c (miR-29c) in regulating the sensitivities of nasopharyngeal carcinoma (NPC) to ionizing radiation (IR) and cisplatin. Low expression of miR-29c was positively associated with therapeutic resistance in 159 NPC cases. Our further in vitro and in vivo studies illustrated ectopic restoration of miR-29c substantially enhanced the sensitivity of NPC cells to IR and cisplatin treatment by promoting apoptosis. Furthermore, we detected miR-29c repressed expression of anti-apoptotic factors, Mcl-1 and Bcl-2 in NPC tissues and cell lines. These data indicate miR-29c might serve as a potential therapeutic sensitizer in NPC treatment.

Anthracyclines disrupt telomere maintenance by telomerase through inducing PinX1 ubiquitination and degradation

Telomere maintenance is essential for cancer growth. Induction of telomere dysfunction, for example, by inhibition of telomeric proteins or telomerase, has been shown to strongly enhance cancer cells’ sensitivity to chemotherapies. However, it is not clear whether modulations of telomere maintenance constitute cancer cellular responses to chemotherapies. Furthermore, the manner in which anti-cancer drugs affect telomere function remains unknown. In this study, we show that anthracyclines, a class of anti-cancer drugs widely used in clinical cancer treatments, have an active role in triggering telomere dysfunction specifically in telomerase-positive cancer cells. Anthracyclines interrupt telomere maintenance by telomerase through the downregulation of PinX1, a protein factor responsible for targeting telomerase onto telomeres, thereby inhibiting telomerase association with telomeres. We further demonstrate that anthracyclines downregulate PinX1 by inducing this protein degradation through the ubiquitin–proteasome-dependent pathway. Our data not only reveal a novel action for anthracyclines as telomerase functional inhibitors but also provide a clue for the development of novel anti-cancer drugs based on telomerase/telomere targeting, which is actively investigated by many current studies.

Intensive expression of Bmi-1 is a new independent predictor of poor outcome in patients with ovarian carcinoma

BackgroundIt has been suggested that the B-cell specific moloney leukemia virus insertion site 1 (Bmi-1) gene plays an oncogenic role in several types of human cancer, but the status of Bmi-1 amplification and expression in ovarian cancer and its clinical/prognostic significance are unclear.MethodsThe methods of immunohistochemistry and fluorescence in situ hybridization were utilized to examine protein expression and amplification of Bmi-1 in 30 normal ovaries, 30 ovarian cystadenomas, 40 borderline ovarian tumors and 179 ovarian carcinomas.ResultsIntensive expression of Bmi-1 was detected in none of the normal ovaries, 3% cystadenomas, 10% borderline tumors, and 37% ovarian carcinomas, respectively. Amplification of Bmi-1 was detected in 8% of ovarian carcinomas. In ovarian carcinomas, significant positive associations were found between intensive expression of Bmi-1 and the tumors ascending histological grade, later pT/pN/pM and FIGO stages (P < 0.05). In univariate survival analysis of the ovarian carcinoma cohorts, a significant association of intensive expression of Bmi-1 with shortened patient survival (mean 49.3 months versus 100.3 months, p < 0.001) was demonstrated. Importantly, Bmi-1 expression provided significant independent prognostic parameters in multivariate analysis (p = 0.005).ConclusionsThese findings provide evidence that intensive expression of Bmi-1 might be important in the acquisition of an invasive and/or aggressive phenotype of ovarian carcinoma, and serve as a independent biomarker for shortened survival time of patients.

Expression of immune-related molecules in primary EBV positive chinese nasopharyngeal carcinoma: Associated with latent membrane protein 1 (LMP1) expression

To understand the role of Epstein-Barr virus (EBV) and viral products in associated with immunophenotype and clinical outcome of primary nasopharyngeal carcinoma (NPC), the expression levels of chemokines IFN-γ-induced protein 10 (IP-10, CXCL10), stromal-derived factor-1 (SDF-1, CXCL12) and its receptor CXCR4 was investigated in 56 primary NPC biopsy specimens from Chinese NPC patients in parallels with LMP1 antigen and EBER1 by immunohistochemisty (IHC) and in situ hybridization (ISH). Moreover, the expression levels of HLA class I (β-microglobulin) and II antigen (HLA-DR), and co-stimulatory molecule CD54 were also evaluated in 31 out of these 56 patients using immunohistochemisty (IHC). Our results showed that (a) the elevated expression levels of IP10, SDF-1, CXCR4, β-microglobulin, HLA-DR, and CD54 in NPC lesions was 66%, 36%, 30%, 42%, 55% and 69%, respectively. (b) High expression of SDF-1 was observed in advanced NPC (N stage, P

Overexpression of AIB1 predicts resistance to chemoradiotherapy and poor prognosis in patients with primary esophageal squamous cell carcinoma

AIB1 (amplified in breast cancer 1) is frequently overexpressed in esophageal squamous cell carcinoma (ESCC), but the significance of AIB1 expression in chemoradiotherapy (CRT) sensitivity and its effect on prognosis are still unclear. In this study, the expression of AIB1 was examined by immunohistochemistry in 98 biopsy specimens of primary ESCC patients treated with definitive CRT. AIB1 overexpression was found in 63/98 (64.3%) of the ESCCs. There was a significant association between AIB1 overexpression and distant lymph node metastases (P = 0.011), but not regional lymph node metastases. In the M0 subgroup, overexpression of AIB1 was observed more frequently in stage T4 than in stage T2–3 (66.7%vs 38.5%, P = 0.031). In addition, AIB1 expression was the only factor that showed a significant correlation with CRT response, in which overexpression of AIB1 was observed more frequently in the CRT resistant group than in the CRT effective group (86.5%vs 50.8%, P < 0.001). Univariate analysis revealed that AIB1 overexpression was associated with poor progression‐free survival (PFS) (P < 0.001) and poor disease‐specific survival (DSS) (P <0.001). Furthermore, AIB1 expression could stratify patient survival in stages T2–3, T4, N1, and M0 (P < 0.05), as well as in the CRT effective group (P < 0.05), and AIB1 overexpression and CRT resistance were evaluated as significant independent prognostic factors for both PFS and DSS in multivariate analysis. These findings suggest that overexpression of AIB1 is a useful predictor of CRT resistance and an independent molecular marker of poor prognosis for ESCC patients. (Cancer Sci 2009; 100: 1591–1596)

Cell cycle-related kinase supports ovarian carcinoma cell proliferation via regulation of cyclin D1 and is a predictor of outcome in patients with ovarian carcinoma

Our previous study has suggested that the cell cycle‐related kinase (CCRK) is a putative candidate oncogene in glioblastoma tumorigenesis. The potential oncogenic role of CCRK and its clinical/prognostic significance, however, in ovarian carcinoma are unclear. In this study, CCRK expression was examined by immunohistochemistry in a series of ovarian carcinoma tissues. Overexpression of CCRK was detected in 53% of the ovarian carcinomas, and it was positively correlated with an ascending histological grade and/or advanced clinical stage of the disease (p < 0.05). In addition, overexpression of CCRK in ovarian carcinoma was determined to be a strong and an independent predictor of short overall survival (p < 0.05). In ovarian carcinoma cells, CCRK knockdown by RNAi led to a G1 phase cell cycle arrest, while CCRK overexpression by stable transfection of CCRK‐containing plasmid pcDNA‐CCRK promoted cell proliferation in vitro and tumor growth in vivo. In addition, CCRK knockdown was found to reduce cyclin D1 expression. Consistently, CCRK overexpression increased cyclin D1 expression, and furthermore, a significant correlation between expression of CCRK and cyclin D1 in ovarian carcinomas was observed (p < 0.001). These findings suggest a potential important role of CCRK in the control of cell proliferation via regulation of cyclin D1 expression, and the overexpression of CCRK, as detected by immunohistochemistry, is an independent molecular marker for shortened survival time of patients with ovarian carcinoma.

Overexpression of the secretory small GTPase Rab27B in human breast cancer correlates closely with lymph node metastasis and predicts poor prognosis

BackgroundThe secretory small GTPase Rab27b was recently identified as an oncogene in breast cancer (BC) in vivo and in vitro studies. This research was designed to further explore the clinical and prognostic significance of Rab27B in BC patients.MethodsThe mRNA/protein expression level of Rab27B was examined by performing Real-time PCR, western blot, and immunohistochemistry (IHC) assays in 12 paired BC tissues and matched adjacent noncancerous tissues (NAT). Then we carried out IHC assay in a large cohort of 221 invasive BC tissues, 22 normal breast tissues, 40 fibroadenoma (FA), 30 ductual carcinoma in situ (DCIS) and 40 metastatic lymph nodes (LNs). The receiver operating characteristic curve method was applied to obtain the optimal cutoff value for high Rab27B expression. Epithelial-mesenchymal transition (EMT) marker expression levels were detected in relation to Rab27B expression.ResultsWe observed that the increased expression of Rab27B was dependent upon the magnitude of cancer progression (P < 0.001). The elevated expression of Rab27B was closely correlated with lymph node metastasis, advanced clinical stage, ascending pathology classification, and positive ER status. Furthermore, patients with high expression of Rab27B had inferior survival outcomes. Multivariate Cox regression analysis proved that Rab27B was a significantly independent risk factor for patients’ survival (P < 0.001). Furthermore, a significant positive relationship was observed between Rab27B expression and elevated mesenchymal EMT markers.ConclusionOur findings suggest that overexpression of Rab27B in BC coincides with lymph node metastasis and acquisition of a poor prognostic phenotype.

Evaluation of serum clusterin as a surveillance tool for human hepatocellular carcinoma with hepatitis B virus related cirrhosis

Background and Aim:  Hepatocellular carcinoma (HCC) is a common human cancer worldwide. The levels of serum clusterin in HCC patients and its potential diagnostic significance is not clear. We aimed to evaluate the clinical use of serum clusterin levels as a surveillance tool for HCC with hepatitis B virus (HBV) related cirrhosis.

Low expression of BARX2 in human primary hepatocellular carcinoma correlates with metastasis and predicts poor prognosis

The homeobox gene Barx2 was recently identified as a regulator of ovarian and breast cancer; however, the expression level of BARX2 and its significance in hepatocellular carcinoma (HCC) remain unknown.