Hui Yun Wang

Genome-wide scan for familial nasopharyngeal carcinoma reveals evidence of linkage to chromosome 4.

Nasopharyngeal carcinoma (NPC) occurs with high frequency in Asian populations, especially among people of Cantonese ancestry. In areas with high incidence, NPC clusters in families, which suggests that both geography and genetics may influence disease risk. Although the HLA-Bw46 locus is associated with increased risk of NPC, no predisposing genes have been identified so far. Here we report the results of a genome-wide search carried out in families at high risk of NPC from Guangdong Province, China. Parametric analyses provide evidence of linkage to the D4S405 marker on chromosome 4 with a logarithm of odds for linkage (lod) score of 3.06 and a heterogeneity-adjusted lod (hlod) score of 3.21. Fine mapping with additional markers flanking D4S405 resulted in a lod score of 3.54 and hlod score of 3.67 for the region 4p15.1–q12. Multipoint nonparametric linkage analysis gives lod scores of 3.54 at D4S405 (P = 5.4 × 10−5) and 4.2 at D4S3002 (P = 1.1 × 10−5), which is positioned 4.5 cM away from D4S405. When Epstein–Barr virus antibody titer was included as a covariate, the lod scores reached 4.70 (P = 2.0 × 10−5) and 5.36 (P = 4.36 × 10−6) for D4S405 and D4S3002, respectively. Our findings provide evidence of a major susceptibility locus for NPC on chromosome 4 in a subset of families.

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.

Downregulation of Six MicroRNAs Is Associated with Advanced Stage, Lymph Node Metastasis and Poor Prognosis in Small Cell Carcinoma of the Cervix

Background Small cell carcinoma of the cervix (SCCC) is very rare, and due to the long time period required to recruit sufficient numbers of patients, there is a paucity of information regarding the prognostic factors associated with survival. MicroRNAs (miRNAs) have been used as cancer-related biomarkers in a variety of tumor types, and the objective of this study was to determine whether microRNA expression profiles can predict clinical outcome in SCCC. Methodology/Principal Findings Forty-four patients with SCCC who underwent radical hysterectomy between January 2000 and October 2009 were enrolled. Using the GeneCopoeia All-in-One™ Customized Human qPCR Primer Array, the expression profiles of 30 miRNAs associated with tumor metastasis was obtained from the formalin-fixed paraffin embedded samples of all 44 patients. Seven miRNAs, has-let-7c, has-miR-10b, has-miR-100, has-miR-125b, has-miR-143, has-miR-145 and has-miR-199a-5p were significantly down-regulated in advanced stage SCCCpatients (FIGO IB2-IV) compared to early stage SCCC patients (FIGOIB1). Among, downregulation of six miRNAs, has-let-7c, has-miR-100, has-miR-125b, has-miR-143, has-miR-145 and has-miR-199a-5p were significantly associated with lymph node metastasis and reduced survival in SCCC. Kaplan–Meier survival analyses revealed that SCCC patients with low expression of has-miR-100 (P = 0.019) and has-miR-125b (P = 0.020) projected a significant tendency towards poorer prognosis. Conclusions/Significance This study demonstrates that downregulation of 7 miRNA associated with advanced stage, 6 miRNAs with metastasis and 2 with poor prognosis in SCCC. Functional analysis of these miRNAs may enhance our understanding of SCCC, as altered expression of specific miRNAs may regulate the metastatic pathway and provide novel targets for therapy.

Clinical Significance and Prognostic Value of microRNA Expression Signatures in Hepatocellular Carcinoma

Purpose: MicroRNAs (miRNAs) play important roles in the development and progression of cancer. The aim of this study is to identify miRNA expression signatures in hepatocellular carcinoma and delineate their clinical significance for hepatocellular carcinoma. Experimental Design: Patients with hepatocellular carcinoma, undergoing hepatectomy were randomly divided into training set (60 patients) and test set (50 patients). Other 56 patients were used as an independent cohort. The miRNA expression levels were detected by microarray and verified by quantitative real-time reverse transcription-PCR (qRT-PCR). Results: A 30-miRNA signature consisting of 10 downregulated and 20 upregulated miRNAs was established for distinguishing hepatocellular carcinoma from noncancerous liver tissues in the training set with 99.2% accuracy. The classification accuracies of this signature were 97% and 90% in the test set and independent cohort, respectively. The expression level of four miRNAs in the 30-miRNA signature was verified by qRT-PCR in the training set. Twenty miRNAs were then selected to construct prognostic signature in the training set. Of the 20 miRNAs, six were risk factors and 14 were protective factors. A formula based on the 20 miRNAs was built to compute prognostic index. Kaplan–Meier analysis showed that patients with a higher prognostic index had a significantly lower survival than those with a low index. This was verified in the test and independent sets. Multivariate analysis indicated that the 20-miRNA signature was an independent prognostic predictor. Conclusions: The 30- and 20-miRNA signatures identified in this study should provide new molecular approaches for diagnosis and prognosis of patients with hepatocellular carcinoma and clues for elucidating molecular mechanism of hepatocarcinogenesis. Clin Cancer Res; 19(17); 4780–91. ©2013 AACR.

Overexpression of karyopherin-2 in epithelial ovarian cancer and correlation with poor prognosis

OBJECTIVES: To evaluate karyopherin 2 (KPNA2) as a biomarker for epithelial ovarian cancer. METHODS: A candidate oncogene, KPNA2, was identified in gene microarray assays of epithelial ovarian cancer tissues compared with normal human ovarian surface epithelial tissues. Differences in expression were further validated by real-time polymerase chain reaction and Western blotting. KPNA2 expression patterns in epithelial ovarian cancer tissues were determined using immunohistochemistry and were compared with specific clinicopathologic features of the patient specimens analyzed. Factors associated with patient survival were also statistically analyzed. RESULTS: KPNA2 was found to be upregulated approximately eightfold in epithelial ovarian cancer tissues compared with human ovarian surface epithelial tissues, and overexpression was detected at the level of both transcription and translation. Immunohistochemical assays detected positive KPNA2 expression (++ or +++) in 50 of 102 (49.0%) epithelial ovarian cancer specimens, whereas negative KPNA2 expression (− or +) was observed in all of the human ovarian surface epithelial tissues analyzed. KPNA2 overexpression was also found to be significantly associated with specific histologic type, an advanced stage, a high histologic grade, and tumor recurrence (P<.05). The 5-year overall survival rate for KPNA2-negative compared with KPNA2-positive patients was 73.1% and 60.5%, respectively (P<.05). CONCLUSION: KPNA2 may play an important role in the development, differentiation, and carcinogenesis of epithelial ovarian cancer and therefore could be an indicator of poor prognosis for patients with epithelial ovarian cancer. LEVEL OF EVIDENCE: II

Identification of a gene-expression signature for predicting lymph node metastasis in patients with early stage cervical carcinoma.

Pelvic lymph node metastasis (PLNM) is an important prognostic factor for patients with cervical carcinoma. The objective of this study was to identify a gene‐expression signature that could predict PLNM in cervical carcinoma.

The Novel Gene Locus for Agenesis of Permanent Teeth (He-Zhao deficiency) Maps to Chromosome 10q11.2

He-Zhao deficiency has been recently characterized with a distinct form of agenesis of permanent teeth that is different from other previously reported disorders of tooth agenesis. This inherited abnormality suggests that some gene(s) associated with the development of permanent teeth may mutate. In this study, we map the gene locus to chromosome 10q11.2. The DNA pooling method combined with two-point and multi-point linkage analysis has been successfully applied. The maximum LOD (Zmax) scores for two-point and multi-point analyses are 13.29 (on marker D10S196) at recombination fraction (θ) = 0 and 18.09 (between markers D10S1772 and D10S1766), respectively. Haplotype analysis confined the locus within an interval of 5.5 cM flanked by markers D10S604 and D10S568. This study has demonstrated a novel gene locus responsible for He-Zhao deficiency and provides a good likelihood for the discovery of one of the genes determining permanent tooth formation and development.

miR-29b suppresses tumor growth and metastasis in colorectal cancer via downregulating Tiam1 expression and inhibiting epithelial-mesenchymal transition.

Recently, the role of miR-29b in colorectal carcinoma (CRC) development appears to be controversial. Until now, the expression and function of miR-29b in CRC have not been clarified clearly. We showed that decreased expression of miR-29b usually occurred in CRC cell lines and tissue samples. Loss- and gain-of-function assays in vitro revealed suppressive effects of miR-29b on cell proliferation and migration. Endogenous overexpression of miR-29b was sufficient to suppress aggressive behavioral phenotypes in mice. Proteomic analysis showed that miR-29b involved in integrate several key biological processes. In addition, miR-29b mediated the inhibition of epithelial–mesenchymal transition (EMT) and the inactivation of mitogen-activated protein kinase and phosphatidylinositol-4,5-bisphosphate 3-kinase/AKT signal transduction pathway. Further studies found that T lymphoma invasion and metastasis 1 (Tiam1) was identified as a direct target of miR-29b. In contrast to the phenotypes induced by miR-29b restoration, Tiam1-induced cell proliferation and migration partly rescued miR-29b-mediated biological behaviors. Our results illustrated that miR-29b as a suppressor has a critical role in CRC progression, which suggests its potential role in the molecular therapy of patients with advanced CRC.

Sevoflurane induces short-term changes in proteins in the cerebral cortices of developing rats.

Exposure to intravenous or inhaled anesthetic agents has potential deleterious effects on the developing brain. However, the mechanisms are not clear. Herein, we investigated protein expression changes in neonatal rat brains after exposure to sevoflurane, an inhalational anesthetic commonly used for pediatric patients.

Prognostic significance of low DICER expression regulated by miR-130a in cervical cancer

Dicer is crucial for the maturation of microRNAs (miRNAs) and its dysregulation may contribute to tumor initiation and progression. The study explored the clinical implications of Dicer and its post-transcriptional regulation by microRNAs in cervical cancer. qRT-PCR and immunohistochemistry investigated Dicer mRNA and protein levels in cervical cancer tissues. The relationship between Dicer expression and survival was analyzed. MiRNA target prediction identified miRNAs that might target Dicer. Luciferase reporter and gain- or loss-of-function assays were performed. The results showed that 36.7% of cervical cancer cases showed low expression of Dicer mRNA and 63.3% cases showed high expression. At the protein level, 51% cases showed negative expression and 49% cases showed positive expression. Dicer mRNA and protein expressions were significantly associated with distant metastasis and recurrence in cervical cancer (P=0.002 and P=0.012, respectively). Multivariate Cox analysis indicated that low Dicer expression (P=0.016) and tumor stage (P=0.047) were independent predictors. Among the miRNAs predicted to target Dicer, 10 were detected by RT-PCR; their expressions were significantly higher in cervical cancers with lower Dicer expression than in those with higher Dicer expression and were negatively correlated with Dicer expression level (P<0.05). In vitro experiments demonstrated that miR-130a directly targeted Dicer mRNA to enhance migration and invasion in SiHa cells. Finally, survival analysis indicated that higher expression of miR-130a was significantly associated with poor disease-free survival. Taken together, Dicer expression regulated by miR-130a is an important potential prognostic factor in cervical cancer.