Limits...
MicroRNA-519a promotes proliferation and inhibits apoptosis of hepatocellular carcinoma cells by targeting FOXF2.

Shao J, Cao J, Liu Y, Mei H, Zhang Y, Xu W - FEBS Open Bio (2015)

Bottom Line: Importantly, up-regulation of miR-519a reduced the expression of FOXF2 mRNA and protein in Huh7 cells, while down-regulation of miR-519a resulted in increased expression of FOXF2 in SMMC-7721 cells.Mechanistically, the effects of miR-519a knockdown on SMMC-7721 cells were abrogated by FOXF2 repression.In conclusion, miR-519a is a novel prognostic predictor for HCC patients and it may potentiate proliferation and inhibits apoptosis of HCC cells by targeting FOXF2.

View Article: PubMed Central - PubMed

Affiliation: Department of General Surgery, Wuhan General Hospital of Guangzhou Military Command, Wuhan 430070, China.

ABSTRACT
Recent studies report that microRNA-519a (miR-519a) is a novel oncomir, which facilitates the onset and progression of human cancers. However, the clinical significance of miR-519a and its functional role and underlying mechanisms in hepatocellular carcinoma (HCC) are poorly investigated. In the present study, elevated expression of miR-519a was observed in HCC tissues compared with adjacent non-tumor tissues. The increased level of miR-519a expression was significantly correlated with adverse clinical features of HCC including hepatitis B virus (HBV) infection, large tumor size, cirrhosis and advanced tumor-node-metastasis tumor stage. Furthermore, high expression of miR-519a was prominently associated with a poorer 5-year overall survival and recurrence-free survival of HCC patients. Gain- and loss-of function experiments showed that miR-519a overexpression enhanced proliferation and reduced apoptosis of Huh7 cells. By contrast, miR-519a knockdown inhibited SMMC-7721 cell proliferation and induced apoptosis. Importantly, up-regulation of miR-519a reduced the expression of FOXF2 mRNA and protein in Huh7 cells, while down-regulation of miR-519a resulted in increased expression of FOXF2 in SMMC-7721 cells. An inverse correlation between mRNA levels of miR-519a and FOXF2 was observed in HCC tissues. Thus, Forkhead box F2 (FOXF2) was identified as a downstream target of miR-519a in HCC. Mechanistically, the effects of miR-519a knockdown on SMMC-7721 cells were abrogated by FOXF2 repression. In conclusion, miR-519a is a novel prognostic predictor for HCC patients and it may potentiate proliferation and inhibits apoptosis of HCC cells by targeting FOXF2.

No MeSH data available.


Related in: MedlinePlus

FOXF2 is a downstream target of miR-519a in HCC cells. (A) The 3′-UTR of FOXF2 mRNA was found to contain the complementary sequence of miR-519a. (B) Overexpression of miR-519a significantly suppressed the luciferase activity of wt 3′-UTR of FOXF2 but not mt 3′-UTR of FOXF2. Down-regulation of miR-519a resulted in an obvious increase in luciferase activity of wt 3′-UTR of FOXF2. n = 3 repeats with similar results; ∗P < 0.05.
© Copyright Policy - CC BY-NC-ND
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4660191&req=5

f0025: FOXF2 is a downstream target of miR-519a in HCC cells. (A) The 3′-UTR of FOXF2 mRNA was found to contain the complementary sequence of miR-519a. (B) Overexpression of miR-519a significantly suppressed the luciferase activity of wt 3′-UTR of FOXF2 but not mt 3′-UTR of FOXF2. Down-regulation of miR-519a resulted in an obvious increase in luciferase activity of wt 3′-UTR of FOXF2. n = 3 repeats with similar results; ∗P < 0.05.

Mentions: To further dig out the molecular mechanisms by which miR-519a exerts its functional role in HCC cells, we used the publicly available databases (TargetScan 6.2 and MiRanDa) to search for potential downstream target of miR-519a. FOXF2, which was recently identified as an important regulator of the proliferation and apoptosis of HCC cells, was predicted to be a downstream target of miR-519a. As shown in Fig. 4A, overexpression of miR-519a in Huh7 cells significantly decreased the level of FOXF2 mRNA (P < 0.05). And the results of Western blot analysis showed that the level of FOXF2 protein was also significantly reduced after forced expression of miR-519a (P < 0.05, Fig. 4B). In contrast, inhibition of miR-519a in SMMC-7721 cells led to an obvious increased expression level of FOXF2 mRNA (P < 0.05, Fig. 4C) and protein (P < 0.05, Fig. 4D). Furthermore, HCC specimens were subjected to qRT-PCR for FOXF2 mRNA. A statistically significant inverse correlation was revealed by Spearman’s correlation analysis between mRNA levels of miR-519a and FOXF2 (r = −0.683, P < 0.001, Fig. 4E). Next, the complementary sequence of miR-519a was found in the 3′-UTR of FOXF2 mRNA (Fig. 5A), suggesting that miR-519a could bind to the 3′-UTR of FOXF2 mRNA. Then, we determined whether miR-519a could directly interact with the 3′-UTR of FOXF2 mRNA as predicted. The results of luciferase reporter assays demonstrated that overexpression of miR-519a in SMMC-7721 cells significantly inhibited the luciferase activity of FOXF2 with the wild-type (wt) 3′-UTR (P < 0.05, Fig. 5B). No obvious effect was observed in the context of mutant-type (mt) 3′-UTR. Accordingly, down-regulation of miR-519a in SMMC-7721 led to significant elevated luciferase activity of wt FOXF2 3′-UTR (P < 0.05, Fig. 5B) and had no influence on that of mt FOXF2 3′-UTR. Taken together, these results indicate that FOXF2 is a direct downstream target of miR-519a in HCC.


MicroRNA-519a promotes proliferation and inhibits apoptosis of hepatocellular carcinoma cells by targeting FOXF2.

Shao J, Cao J, Liu Y, Mei H, Zhang Y, Xu W - FEBS Open Bio (2015)

FOXF2 is a downstream target of miR-519a in HCC cells. (A) The 3′-UTR of FOXF2 mRNA was found to contain the complementary sequence of miR-519a. (B) Overexpression of miR-519a significantly suppressed the luciferase activity of wt 3′-UTR of FOXF2 but not mt 3′-UTR of FOXF2. Down-regulation of miR-519a resulted in an obvious increase in luciferase activity of wt 3′-UTR of FOXF2. n = 3 repeats with similar results; ∗P < 0.05.
© Copyright Policy - CC BY-NC-ND
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4660191&req=5

f0025: FOXF2 is a downstream target of miR-519a in HCC cells. (A) The 3′-UTR of FOXF2 mRNA was found to contain the complementary sequence of miR-519a. (B) Overexpression of miR-519a significantly suppressed the luciferase activity of wt 3′-UTR of FOXF2 but not mt 3′-UTR of FOXF2. Down-regulation of miR-519a resulted in an obvious increase in luciferase activity of wt 3′-UTR of FOXF2. n = 3 repeats with similar results; ∗P < 0.05.
Mentions: To further dig out the molecular mechanisms by which miR-519a exerts its functional role in HCC cells, we used the publicly available databases (TargetScan 6.2 and MiRanDa) to search for potential downstream target of miR-519a. FOXF2, which was recently identified as an important regulator of the proliferation and apoptosis of HCC cells, was predicted to be a downstream target of miR-519a. As shown in Fig. 4A, overexpression of miR-519a in Huh7 cells significantly decreased the level of FOXF2 mRNA (P < 0.05). And the results of Western blot analysis showed that the level of FOXF2 protein was also significantly reduced after forced expression of miR-519a (P < 0.05, Fig. 4B). In contrast, inhibition of miR-519a in SMMC-7721 cells led to an obvious increased expression level of FOXF2 mRNA (P < 0.05, Fig. 4C) and protein (P < 0.05, Fig. 4D). Furthermore, HCC specimens were subjected to qRT-PCR for FOXF2 mRNA. A statistically significant inverse correlation was revealed by Spearman’s correlation analysis between mRNA levels of miR-519a and FOXF2 (r = −0.683, P < 0.001, Fig. 4E). Next, the complementary sequence of miR-519a was found in the 3′-UTR of FOXF2 mRNA (Fig. 5A), suggesting that miR-519a could bind to the 3′-UTR of FOXF2 mRNA. Then, we determined whether miR-519a could directly interact with the 3′-UTR of FOXF2 mRNA as predicted. The results of luciferase reporter assays demonstrated that overexpression of miR-519a in SMMC-7721 cells significantly inhibited the luciferase activity of FOXF2 with the wild-type (wt) 3′-UTR (P < 0.05, Fig. 5B). No obvious effect was observed in the context of mutant-type (mt) 3′-UTR. Accordingly, down-regulation of miR-519a in SMMC-7721 led to significant elevated luciferase activity of wt FOXF2 3′-UTR (P < 0.05, Fig. 5B) and had no influence on that of mt FOXF2 3′-UTR. Taken together, these results indicate that FOXF2 is a direct downstream target of miR-519a in HCC.

Bottom Line: Importantly, up-regulation of miR-519a reduced the expression of FOXF2 mRNA and protein in Huh7 cells, while down-regulation of miR-519a resulted in increased expression of FOXF2 in SMMC-7721 cells.Mechanistically, the effects of miR-519a knockdown on SMMC-7721 cells were abrogated by FOXF2 repression.In conclusion, miR-519a is a novel prognostic predictor for HCC patients and it may potentiate proliferation and inhibits apoptosis of HCC cells by targeting FOXF2.

View Article: PubMed Central - PubMed

Affiliation: Department of General Surgery, Wuhan General Hospital of Guangzhou Military Command, Wuhan 430070, China.

ABSTRACT
Recent studies report that microRNA-519a (miR-519a) is a novel oncomir, which facilitates the onset and progression of human cancers. However, the clinical significance of miR-519a and its functional role and underlying mechanisms in hepatocellular carcinoma (HCC) are poorly investigated. In the present study, elevated expression of miR-519a was observed in HCC tissues compared with adjacent non-tumor tissues. The increased level of miR-519a expression was significantly correlated with adverse clinical features of HCC including hepatitis B virus (HBV) infection, large tumor size, cirrhosis and advanced tumor-node-metastasis tumor stage. Furthermore, high expression of miR-519a was prominently associated with a poorer 5-year overall survival and recurrence-free survival of HCC patients. Gain- and loss-of function experiments showed that miR-519a overexpression enhanced proliferation and reduced apoptosis of Huh7 cells. By contrast, miR-519a knockdown inhibited SMMC-7721 cell proliferation and induced apoptosis. Importantly, up-regulation of miR-519a reduced the expression of FOXF2 mRNA and protein in Huh7 cells, while down-regulation of miR-519a resulted in increased expression of FOXF2 in SMMC-7721 cells. An inverse correlation between mRNA levels of miR-519a and FOXF2 was observed in HCC tissues. Thus, Forkhead box F2 (FOXF2) was identified as a downstream target of miR-519a in HCC. Mechanistically, the effects of miR-519a knockdown on SMMC-7721 cells were abrogated by FOXF2 repression. In conclusion, miR-519a is a novel prognostic predictor for HCC patients and it may potentiate proliferation and inhibits apoptosis of HCC cells by targeting FOXF2.

No MeSH data available.


Related in: MedlinePlus