Down-Regulation of miR-141 Induced by Helicobacter Pylori Promotes the Invasion of Gastric Cancer by Targeting STAT4

Self Cite

201

148

Background/Aims: Non-coding RNAs including miRNA and lncRNA had been reported to regulate gene expression and were both related to cancer progression. MicroRNA-141 (miR-141) has been reported to play a role in the epithelial to mesenchymal transition (EMT) process and H19 has also been demonstrated to promote malignancy in various cancers. We aimed to determine the correlation between miR-141 and H19 and their roles in gastric cancer in this study. Methods: H19 and miR-141 expression were detected by qRT-PCR. By bioinformatic analysis and luciferase assay we examined the correlation between H19 and miR-141 in vitro. Results: H19 expression was found to be inversely correlated to miR-141 expression in gastric cancer cells and tissues. H19 promotes malignancy including proliferation and invasion whereas miR-141 suppresses malignancy in human cancer cells. MiR-141 binds to H19 in a sequence specific manner, and suppresses H19 expression and functions including proliferation and invasion. MiR-141 could also regulate H19 target genes and miR-141 inhibitor restores H19 siRNA function, while H19 regulates miR-141 target gene ZEB1. Conclusion: These results were the first to demonstrate that H19 and miR-141 could compete with each other and affect their target genes in gastric cancer, which provide important clues for understanding the key roles of lncRNA-miRNA functional network in cancer.

Section: Discussionmentioning

confidence: 99%

The Interaction Between MiR-141 and lncRNA-H19 in Regulating Cell Proliferation and Migration in Gastric Cancer

Zhou

Feng

Yin

et al. 2015

Self Cite

201

148

“…The nucleotide sequences of specific primers for the selected genes were as follows: RNF43 forward primer: (5-AGCATGAGTGGTGGCCACCAG-3), reverse primer (5-ATCTCACACAGCCTGTTCAC-3); and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) forward primer: (5-CCACCCATGGCAAAATTCCATGGCA-3), reverse primer: (5-TCTAGACGGCAGGTCAGGTCCACC-3). The relative values of the expressions of the transcripts were calculated using the 2 - ∆∆ C (T) method [11,12]. The mRNA expression level of RNF43 was normalized to that of GAPDH.…”

Section: Methodsmentioning

confidence: 99%

RNF43 Inhibits Cancer Cell Proliferation and Could be a Potential Prognostic Factor for Human Gastric Carcinoma

Niu

Qin

et al. 2015

Background/Aims: RNF43 is a member of transmembrane E3 ubiquitin ligases and plays important roles in tumor formation progression. In current study, we aimed to explore RNF43 expression and analyze its role in gastric carcinoma. Methods and Results: The level of RNF43 was detected in 77 cases of gastric carcinoma and matched normal tissues by real-time PCR, western blotting and immunohistochemistry. We found that the expression of RNF43 was significantly down-regulated in the gastric carcinoma tissues compared to the normal mucosae (all P<0.001). In addition, RNF43 was significantly correlated with histological differentiation (P = 0.001), T-stage cancer (P<0.001), depth of invasion (P<0.001), metastasis of regional lymph nodes (P<0.001), pTNM stage (P<0.001) and survival (P = 0.021). We further explored the biological functions of RNF43 in gastric carcinoma cell lines. Both gain- and loss-function assays show that RNF43 could suppress cell proliferation while promotes cell apoptosis. Further, we found that RNF43 was positively correlated with p53 and cleaved-caspase3 and negatively correlated with Ki67 and Lgr5. Concolusion: In conclusion, RNF43 might act as a tumor suppressor in gastric carcinoma and might be a potential indicator for the clinical assessment of gastric cancer prognosis

“…For instance, miR-21 has been found to be overexpressed in GC and to promote tumor proliferation and invasion by negatively regulating important tumor suppressor genes such as PTEN, PDCD4, and RECK [19,20,21]. By contrast, overexpression of miR-141 could suppress GC cell invasion by directly repressing STAT4 [22]. However, it remains unclear whether miRNAs can regulate the expression of FOXQ1 in GC; therefore, we aimed to determine the target miRNAs of FOXQ1.…”

Section: Introductionmentioning

confidence: 99%

MiR-1271 Inhibits Cell Proliferation, Invasion and EMT in Gastric Cancer by Targeting FOXQ1

Xiang

Deng

Liu

et al. 2015

Background/Aims: FOXQ1 overexpression has been reported to enhance tumor growth and invasion. However, the biological function of FOXQ1 and the mechanism underlying its upregulation in gastric cancer (GC) remain unknown. Methods: QPCR was used to detect the expression of miR-1271 and FOXQ1 in specimens from GC patients. FOXQ1-siRNA, and miR-1271 mimics and inhibitor were transfected into human MGC-803 and SGC-7901 cells. The transwell assay was used to examine the cell invasive ability. The regulation mechanism was confirmed by luciferase reporter assay. Markers of epithelial-mesenchymal transition (EMT) were detected by western blot analysis. Results: MiR-1271 was downregulated in both GC tissues and GC cell lines. The expression of miR-1271 was inversely correlated with tumor size (P = 0.017), tumor stage (P = 0.035), lymph node metastasis (P = 0.018), and TNM stage (P = 0.025). Ectopic expression of miR-1271 dramatically suppressed GC cell proliferation, invasion, and EMT. Furthermore, FOXQ1 was identified as a direct target of miR-1271. Knockdown of FOXQ1 inhibited GC cell malignant behavior, whereas FOXQ1 overexpression partially restored the suppression effects of miR-1271. Additionally, miR-1271 expression was negatively correlated with FOXQ1 in GC tissues. Conclusions: MiR-1271 inhibits cell proliferation, invasion, and EMT in GC by directly suppressing FOXQ1 expression.