MicroRNAs （miRNAs） play an important role in carcinogenesis in various solid cancers including breast can-cer. Down-regulation of microRNA-148a （miR-148a） has been reported in certain cancer types. However, the bi...MicroRNAs （miRNAs） play an important role in carcinogenesis in various solid cancers including breast can-cer. Down-regulation of microRNA-148a （miR-148a） has been reported in certain cancer types. However, the biological role of miR-148a and its related targets in breast cancer are unknown yet. In this study, we showed that the level of miR-148a was lower in MCF7 cells than that in MCF10A cells. V-erb-b2 erythroblastic leukemia viral oncogene homolog 3 （ERBB3） is a direct target of miR-148a in human breast cancer cells through direct binding of miR-148a to ERBB3 3’-UTR region. Overexpression of miR-148a in MCF7 cells inhibited ERBB3 expression, blocked the downstream pathway activation including activation of AKT, ERK1/2, and p70S6K1, and decreased HIF-1α expression. Furthermore, forced expression of miR-148a attenuated tumor angiogenesis in vivo. Our re-sults identify ERBB3 as a direct target of miR-148a, and provide direct evidence that miR-148a inhibits tumor an-giogenesis through ERBB3 and its downstream signaling molecules. This information would be helpful for target-ing the miR-148a/ERBB3 pathway for breast cancer prevention and treatment in the future.展开更多
基金supported by grants of the National Natural Science Foundation of China (No.30871296 and No.81071642)
文摘MicroRNAs （miRNAs） play an important role in carcinogenesis in various solid cancers including breast can-cer. Down-regulation of microRNA-148a （miR-148a） has been reported in certain cancer types. However, the biological role of miR-148a and its related targets in breast cancer are unknown yet. In this study, we showed that the level of miR-148a was lower in MCF7 cells than that in MCF10A cells. V-erb-b2 erythroblastic leukemia viral oncogene homolog 3 （ERBB3） is a direct target of miR-148a in human breast cancer cells through direct binding of miR-148a to ERBB3 3’-UTR region. Overexpression of miR-148a in MCF7 cells inhibited ERBB3 expression, blocked the downstream pathway activation including activation of AKT, ERK1/2, and p70S6K1, and decreased HIF-1α expression. Furthermore, forced expression of miR-148a attenuated tumor angiogenesis in vivo. Our re-sults identify ERBB3 as a direct target of miR-148a, and provide direct evidence that miR-148a inhibits tumor an-giogenesis through ERBB3 and its downstream signaling molecules. This information would be helpful for target-ing the miR-148a/ERBB3 pathway for breast cancer prevention and treatment in the future.
