LncRNA MAGI2‐AS3 inhibits hepatocellular carcinoma cell proliferation and migration by targeting the miR‐374b‐5p/SMG1 signaling pathway

Abstract Long noncoding RNAs (lncRNAs) have been proven to play critical roles in cancer progression. Recently, lncRNA MAGI2‐AS3 has been revealed to be a tumor suppressor and inhibit cell growth by targeting the Fas/FasL signalling pathway in breast cancer. However, the role and underlying mechanism of MAGI2‐AS3 in hepatocellular carcinoma (HCC) remain largely unknown. In the current study, we found that MAGI2‐AS3 expression is downregulated in HCC tissues and closely associated with some clinical characteristics (tumor size, lymph node metastasis, and TNM stage) and poor overall survival. Overexpression of MAGI2‐AS3 inhibits HCC cell proliferation and migration in vitro, while impedes tumor growth in vivo accordantly. In addition, our data suggest that MAGI2‐AS3 could function as an endogenous sponge of miR‐374b‐5p by directly binding to it and suppressing its expression. Furthermore, miR‐374b‐5p upregulation could restore the inhibitory effect of MAGI2‐AS3 on HCC cells processes. Moreover, suppressor with morphogenetic effect on genitalia family member 1 (SMG1) is positively regulated by MAGI2‐AS3 via absorbing miR‐374b‐5p in HCC cells. More important, SMG1 knockdown reverses the suppressive function of MAGI2‐AS3 in HCC cell processes. Taken together, we reveal a functional MAGI2‐AS3/miR‐374b‐5p/SMG1 axis that suppresses HCC progression, potently suggesting a new road for HCC treatment.