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Kong R.,Clinical Medical Examination Center | Kong R.,Nanjing Medical University | Zhang E.-B.,Nanjing Medical University | Yin D.-D.,Cancer Therapy and Research Center | And 9 more authors.
Molecular Cancer | Year: 2015

Background: Mounting evidence indicates that long noncoding RNAs (lncRNAs) could play a pivotal role in cancer biology. However, the overall biological role and clinical significance of PVT1 in gastric carcinogenesis remains largely unknown. Methods: Expression of PVT1 was analyzed in 80 GC tissues and cell lines by qRT-PCR. The effect of PVT1 on proliferation was evaluated by MTT and colony formation assays, and cell apoptosis was evaluated by Flow-cytometric analysis. GC cells transfected with shPVT1 were injected into nude mice to study the effect of PVT1 on tumorigenesis in vivo. RIP was performed to confirm the interaction between PVT1 and EZH2. ChIP was used to study the promoter region of related genes. Results: The higher expression of PVT1 was significantly correlated with deeper invasion depth and advanced TNM stage. Multivariate analyses revealed that PVT1 expression served as an independent predictor for overall survival (p=0.031). Further experiments demonstrated that PVT1 knockdown significantly inhibited the proliferation both in vitro and in vivo. Importantly, we also showed that PVT1 played a key role in G1 arrest. Moreover, we further confirmed that PVT1 was associated with enhancer of zeste homolog 2 (EZH2) and that this association was required for the repression of p15 and p16. To our knowledge, this is the first report showed that the role and the mechanism of PVT1 in the progression of gastric cancer. Conclusions: Together, these results suggest that lncRNA PVT1 may serve as a candidate prognostic biomarker and target for new therapies in human gastric cancer. © Kong et al. Source

Xu T.-P.,Nanjing Medical University | Liu X.-X.,Yangzhou University | Xia R.,Nanjing Medical University | Yin L.,Nanjing Medical University | And 4 more authors.
Oncogene | Year: 2015

The long noncoding RNA TINCR shows aberrant expression in human squamous carcinomas. However, its expression and function in gastric cancer remain unclear. We report that TINCR is strongly upregulated in human gastric carcinoma (GC), where it was found to contribute to oncogenesis and cancer progression. We also revealed that TINCR overexpression is induced by nuclear transcription factor SP1. Silencing TINCR expression inhibited cell proliferation, colony formation, tumorigenicity and apoptosis promotion, whereas TINCR overexpression promoted cell growth, as documented in the SGC7901 and BGC823 cell lines. Mechanistic analyses indicated that TINCR could bind to STAU1 (staufen1) protein, and influence KLF2 mRNA stability and expression, then KLF2 regulated cyclin-dependent kinase genes CDKN1A/P21 and CDKN2B/P15 transcription and expression, thereby affecting the proliferation and apoptosis of GC cells. Together, our findings suggest that TINCR contributes to the oncogenic potential of GC and may constitute a potential therapeutic target in this disease. © 2015 Macmillan Publishers Limited. Source

Han D.,Clinical Medical Examination Center | Tang H.,Northern Jiangsu Peoples Hospital | Ren C.,Clinical Medical Examination Center | Wang G.,Clinical Medical Examination Center | And 2 more authors.
Frontiers in Microbiology | Year: 2015

The population structure of clinical Vibrio parahaemolyticus isolates spreading in China remains undefined. We brought 218 clinical isolates from the pubMLST database originating from different regions of China collected since the year of 1990, analyzed by multilocus sequence typing (MLST), to elucidate the prevalence and genetic diversity of V. parahaemolyticus circulating in Chinese population. The MLST scheme produced 137 sequence types (STs). These STs were clustered into six clonal complexes (CCs), six doublets, and 91 singletons, exhibiting a high level of genetic diversity. However, less diversity was displayed on the peptide level: only 46 different peptide sequence type (pST) were generated, with pST2 (44.0%, 96/218) and pST1 (15.1%, 33/218) the predominant. Further analysis confirmed all the pSTs belong to a single complex founded by pST1, pST2, pST3, and pST4. recA presented the highest degree of nucleotide diversity (0.026) and the largest number of variable sites (176) on the nucleotide level. pyrC was the most diverse locus on the peptide level, possessing the highest percentage of variable sites (9.2%, 15/163). Significant linkage disequilibrium with the alleles was detected when the Standardized Index of Association (IS A) was calculated both for the entire isolates collection (0.7169, P < 0.01) and for the 137 STs (IS A = 0.2648, P < 0.01). In conclusion, we provide an overview of prevalence and genetic diversity of clinical V. parahaemolyticus spreading in Chinese population using MLST analysis. The results would offer genetic evidences for uncovering the microevolution relationship of V. parahaemolyticus populations. © 2015 Han, Tang, Ren, Wang, Zhou and Han. Source

Han C.,Clinical Medical Examination Center | Tang H.,Experimental Research Center | Ren C.,Clinical Medical Examination Center | Zhu X.,Clinical Medical Examination Center | Han D.,Clinical Medical Examination Center
Frontiers in Microbiology | Year: 2016

Pandemic Vibrio parahaemolyticus is an emerging public health concern as it has caused numerous gastroenteritis outbreaks worldwide. Currently, the absence of a global overview of the phenotypic and molecular characteristics of pandemic strains restricts our overall understanding of these strains, especially for environmental strains. To generate a global picture of the sero-prevalence and genetic diversity of pandemic V. parahaemolyticus, pandemic isolates from worldwide collections were selected and analyzed in this study. After a thorough analysis, we found that the pandemic isolates represented 49 serotypes, which are widely distributed in 22 countries across four continents (Asia, Europe, America and Africa). All of these serotypes were detected in clinical isolates but only nine in environmental isolates. O3:K6 was the most widely disseminated serotype, followed by O3:KUT, while the others were largely restricted to certain countries. The countries with the most abundant pandemic serotypes were China (26 serotypes), India (24 serotypes), Thailand (15 serotypes) and Vietnam (10 serotypes). Based on MLST analysis, 14 sequence types (STs) were identified among the pandemic strains, nine of which fell within clonal complex (CC) 3. ST3 and ST305 were the only two STs that have been reported in environmental pandemic strains. Pandemic ST3 has caused a wide range of infections in as many as 16 countries. Substantial serotypic diversity was mainly observed among isolates within pandemic ST3, including as many as 12 combinations of O/K serotypes. At the allele level, the dtdS and pntA, two loci that perfectly conserved in CC3, displayed a degree of polymorphism in some pandemic strains. In conclusion, we provide a comprehensive understanding of sero-prevalence and genetic differentiation of clinical and environmental pandemic isolates collected from around the world. Although, further studies are needed to delineate the specific mechanisms by which the pandemic strains evolve and spread, the findings in this study are helpful when seeking countermeasures to reduce the spread of V. parahaemolyticus in endemic areas. © 2016 Han, Tang, Ren, Zhu and Han. Source

Han D.,Clinical Medical Examination Center | Tang H.,Northern Jiangsu Peoples Hospital | Lu J.,Northern Jiangsu Peoples Hospital | Wang G.,Clinical Medical Examination Center | And 3 more authors.
PLoS ONE | Year: 2014

Vibrio parahaemolyticus is a leading cause of food-borne gastroenteritis worldwide. Although this bacterium has been the subject of much research, the population structure of clinical strains from worldwide collections remains largely undescribed, and the recorded outbreaks of V. parahaemolyticus gastroenteritis highlight the need for the subtyping of this species. We present a broad phylogenetic analysis of 490 clinical V. parahaemolyticus isolates from 17 coastal countries through multilocus sequence analysis (MLST). The 490 tested isolates fell into 161 sequence types (STs). The eBURST algorithm revealed that the 161 clinically relevant STs belonged to 8 clonal complexes, 11 doublets, and 94 singletons, showing a high level of genetic diversity. CC3 was found to be a global epidemic clone of V. parahaemolyticus, and ST-3 was the only ST with an international distribution. recA was observed to be evolving more rapidly, exhibiting the highest degree of nucleotide diversity (0.028) and the largest number of polymorphic nucleotide sites (177). We also found that the high variability of recA was an important cause of differences between the results of the eBURST and ME tree analyses, suggesting that recA has a much greater influence on the apparent evolutionary classification of V. parahaemolyticus based on the current MLST scheme. In conclusion, it is evident that a high degree of genetic diversity within the V. parahaemolyticus population and multiple sequence types are contributing to the burden of disease around the world. MLST, with a fully extractable database, is a powerful system for analysis of the clonal relationships of strains at a global scale. With the addition of more strains, the pubMLST database will provide more detailed and accurate information, which will be conducive to our future research on the population structure of V. parahaemolyticus. © PLOS ONE 2014. Source

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