Dataset Information

MicroRNA-26a inhibits angiogenesis by down-regulating VEGFA through the PIK3C2?/Akt/HIF-1? pathway in hepatocellular carcinoma.

ABSTRACT:

Background & aims

microRNAs (miRNAs) have been reported to regulate angiogenesis by down-regulating the expression of pro-angiogenic or anti-angiogenic factors. The aims of this study were to investigate whether miR-26a inhibited angiogenesis by down-regulating vascular endothelial growth factor A (VEGFA) and its clinical relevance in hepatocellular carcinoma (HCC).

Methods

The expression of miR-26a was modified in HepG2 and HCCLM3 cell lines respectively, and a panel of angiogenic factors was measured by real-time PCR in the cells. A luciferase reporter assay was used to validate the target gene of miR-26a. Specific inhibitors of signal transduction pathway and siRNA approaches were used to explore the regulatory mechanism of miR-26a. Migration and tube forming assays were conducted to show the changes of angiogenesis induced by miR-26a and its target genes. Finally animal studies were used to further validate those findings.

Results

Ectopic expression of miR-26a exhibited decreased levels of VEGFA in HepG2 cells. Migration and tube forming of human umbilical vein endothelial cells (HUVECs) were decreased in the conditioned medium from ectopic expression of miR-26a in HepG2 cells compared to control HepG2 cells. The pro-angiogenic effects of the conditioned medium of HepG2 cells on HUVECs were specifically decreased by LY294002, YC-1, and bevacizumab. Integrated analysis disclosed PIK3C2? as a downstream target gene of miR-26a. Ectopic expression of miR-26a suppressed ectopic and orthotopic tumor growth and vascularity in nude mice. The results in HCCLM3 were consistent with those in HepG2. miR-26a expression was inversely correlated with VEGFA expression in HCC patients.

Conclusions

miR-26a modulated angiogenesis of HCC through the PIK3C2?/Akt/HIF-1?/VEGFA pathway. The expression of VEGFA was inversely correlated with miR-26a expression in HCC tumors.

SUBMITTER: Chai ZT

PROVIDER: S-EPMC3806796 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Publications

MicroRNA-26a inhibits angiogenesis by down-regulating VEGFA through the PIK3C2α/Akt/HIF-1α pathway in hepatocellular carcinoma.

Chai Zong-Tao ZT Kong Jian J Zhu Xiao-Dong XD Zhang Yuan-Yuan YY Lu Lu L Zhou Jia-Min JM Wang Long-Rong LR Zhang Ke-Zhi KZ Zhang Qiang-Bo QB Ao Jian-Yang JY Wang Miao M Wu Wei-Zhong WZ Wang Lu L Tang Zhao-You ZY Sun Hui-Chuan HC

PloS one 20131023 10

<h4>Background & aims</h4>microRNAs (miRNAs) have been reported to regulate angiogenesis by down-regulating the expression of pro-angiogenic or anti-angiogenic factors. The aims of this study were to investigate whether miR-26a inhibited angiogenesis by down-regulating vascular endothelial growth factor A (VEGFA) and its clinical relevance in hepatocellular carcinoma (HCC).<h4>Methods</h4>The expression of miR-26a was modified in HepG2 and HCCLM3 cell lines respectively, and a panel of angiogeni ...[more]

PMID: 24194905

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