Jing Ping Yun

Prognostic value of a microRNA signature in nasopharyngeal carcinoma: a microRNA expression analysis

BACKGROUND MicroRNAs (miRNAs) can be used as prognostic biomarkers in many types of cancer. We aimed to identify miRNAs that were prognostic in patients with nasopharyngeal carcinoma. METHODS We retrospectively analysed miRNA expression profiles in 312 paraffin-embedded specimens of nasopharyngeal carcinoma from Sun Yat-sen University Cancer Center (Guangzhou, China) and 18 specimens of non-cancer nasopharyngitis. Using an 873 probe microarray, we assessed associations between miRNA signatures and clinical outcome in a randomly selected 156 samples (training set) and validated findings in the remaining 156 samples (internal validation set). We confirmed the miRNAs signature using quantitative RT-PCR analysis in 156 samples from a second randomisation of the 312 samples, and validated the miRNA signature in 153 samples from the West China Hospital of Sichuan University in Chengdu, China (independent set). We used the Kaplan-Meier method and log-rank tests to estimate correlations of the miRNA signature with disease-free survival (DFS), distant metastasis-free survival (DMFS), and overall survival. FINDINGS 41 miRNAs were differentially expressed between nasopharyngeal carcinoma and non-cancer nasopharyngitis tissues. A signature of five miRNAs, each significantly associated with DFS, was identified in the training set. We calculated a risk score from the signature and classified patients as high risk or low risk. Compared with patients with low-risk scores, patients with high risk scores in the training set had shorter DFS (hazard ratio [HR] 2·73, 95% CI 1·46-5·11; p=0·0019), DMFS (3·48, 1·57-7·75; p=0·0020), and overall survival (2·48, 1·24-4·96; p=0·010). We noted equivalent findings in the internal validation set for DFS (2·47, 1·32-4·61; p=0·0052), DMFS (2·28, 1·09-4·80; p=0·030), and overall survival (2·87, 1·38-5·96; p=0·0051) and in the independent set for DFS (3·16, 1·65-6·04; p=0·0011), DMFS (2·39, 1·05-5·42; p=0·037), and overall survival (3·07, 1·34-7·01; p=0·0082). The five-miRNA signature was an independent prognostic factor. A combination of this signature and TNM stage had better prognostic value than did TNM stage alone in the training set (area under receiver operating characteristics 0·68 [95% CI 0·60-0·76] vs 0·60 [0·52-0·67]; p=0·013), the internal validation set (0·70 [0·61-0·78] vs 0·61 [0·54-0·68]; p=0·012), and the independent set (0·70 [0·62-0·78] vs 0·63 [0·56-0·69]; p=0·032). INTERPRETATION Identification of patients with the five-miRNA signature might add prognostic value to the TNM staging system and inform treatment decisions for patients at high risk of progression. FUNDING Science Foundation of Chinese Ministry of Health, National Natural Science Foundation of China, Pearl River Scholar Funded Scheme, Guangdong Key Scientific and Technological Innovation Program, Guangdong Natural Science Foundation, Fundamental Research Funds for the Central Universities.

Nucleophosmin/B23 is a proliferate shuttle protein associated with nuclear matrix.

It has become obvious that a better understanding and potential elucidation of the nucleolar phosphoprotein B23 involving in functional interrelationship between nuclear organization and gene expression. In present study, protein B23 expression were investigated in the regenerative hepatocytes at different periods (at days 0, 1, 2, 3, 4, 7) during liver regeneration after partial hepatectomy on the rats with immunohistochemistry and Western blot analysis. Another experiment was done with immunolabeling methods and two‐dimensional (2‐D) gel electrophoresis for identification of B23 in the regenerating hepatocytes and HepG2 cells (hepatoblastoma cell line) after sequential extraction with detergents, nuclease, and salt. The results showed that its expression in the hepatocytes had a locative move and quantitative change during the process of liver regeneration post‐operation. Its immunochemical localization in the hepatocytes during the process showed that it moved from nucleoli of the hepatocytes in the stationary stage to nucleoplasm, cytoplasm, mitotic spindles, and mitotic chromosomes of the hepatocytes in the regenerating livers. It was quantitatively increased progressively to peak level at day 3 post‐operation and declined gradually to normal level at day 7. It was detected in nuclear matrix protein (NMP) composition extracted from the regenerating hepatocytes and HepG2 cells and identified with isoelectric point (pI) value of 5.1 and molecular weight of 40 kDa. These results indicated that B23 was a proliferate shuttle protein involving in cell cycle and cell proliferation associated with nuclear matrix.

Correlation between expression of p53, p21/WAF1, and MDM2 proteins and their prognostic significance in primary hepatocellular carcinoma

BackgroundTumor Protein p53 (p53), cyclin-dependent kinase inhibitor 1A (p21/WAF1), and murine double minute 2 (MDM2) participate in the regulation of cell growth. Altered expression of these gene products has been found in malignant tumors and has been associated with poor prognosis. Our aim was to investigate the expression of the 3 proteins in hepatocellular carcinoma (HCC) and their prognostic significance.MethodsWe examined p53, p21/WAF1, and MDM2 expression in 181 pairs of HCC tissues and the adjacent hepatic tissues by performing immunohistochemistry and examined the expression of the 3 proteins in 7 pairs of HCC tissues and the adjacent hepatic tissues by using western blot analysis.ResultsThe expression of p53, p21/WAF1, and MDM2 in the HCC tissues was significantly higher than those in the adjacent hepatic tissues (P < 0.05). A statistical correlation was observed between p53 and p21/WAF1 expression in HCC tissues (R = 0.195, P = 0.008). A statistical correlation was observed between expression of p53 and p21/WAF1 (R = 0.380, P = 0.000), p53 and MDM2 (R = 0.299, P = 0.000), p21/WAF1 and MDM2 (R = 0.285, P = 0.000) in 181 liver tissues adjacent to the tumor. Patients with a low pathologic grade HCC (I+II) had a higher tendency to express p53 on tumor cells than the patients with high pathologic grade HCC (III+IV) (P = 0.007). Survival analysis showed that positive p21/WAF1 expression or/and negative MDM2 expression in HCC was a predictor of better survival of patients after tumor resection (P < 0.05).ConclusionsThe proteins p53, p21/WAF1, and MDM2 were overexpressed in all the HCC cases in this study, and p53 and p21/WAF1 overexpression were positively correlated. The expression of p21/WAF1 and MDM2 can be considered as 2 useful indicators for predicting the prognosis of HCC.

Prognostic Significance of SOX2 Expression in Nasopharyngeal Carcinoma

The significance of SOX2 in nasopharyngeal carcinoma (NPC), a tumor associated with Epstein–Barr virus (EBV), remains unclear. Here, we reported that, in the univariate analysis, SOX2 expression was correlated with a poorer distant metastasis-free survival (DMFS). The EBV-VCA/IgA titers in patients with NPC were also associated with a poorer overall survival (OS). Patients with NPC, who had both strong staining of SOX2 and high titers of EBV-VCA/IgA, had the poorest prognoses. Therefore, SOX2 or the combination of the SOX2 expression level and EBV-VCA/IgA titers could be valuable to predict distant metastasis or the prognosis of NPC.

Low BRMS1 expression promotes nasopharyngeal carcinoma metastasis in vitro and in vivo and is associated with poor patient survival

BackgroundBreast cancer metastasis suppressor 1 (BRMS1) is a metastasis suppressor gene. This study aimed to investigate the impact of BRMS1 on metastasis in nasopharyngeal carcinoma (NPC) and to evaluate the prognostic significance of BRMS1 in NPC patients.MethodsBRMS1 expression was examined in NPC cell lines using quantitative reverse transcription-polymerase chain reaction and Western blotting. NPC cells stably expressing BRMS1 were used to perform wound healing and invasion assays in vitro and a murine xenograft assay in vivo. Immunohistochemical staining was performed in 274 paraffin-embedded NPC specimens divided into a training set (n = 120) and a testing set (n = 154).ResultsBRMS1 expression was down-regulated in NPC cell lines. Overexpression of BRMS1 significantly reversed the metastatic phenotype of NPC cells in vitro and in vivo. Importantly, low BRMS1 expression was associated with poor distant metastasis-free survival (DMFS, P < 0.001) and poor overall survival (OS, P < 0.001) in the training set; these results were validated in the testing set and overall patient population. Cox regression analysis demonstrated that low BRMS1 expression was an independent prognostic factor for DMFS and OS in NPC.ConclusionsLow expression of the metastasis suppressor BRMS1 may be an independent prognostic factor for poor prognosis in NPC patients.