Synaptic acetylcholinesterase targeted by microRNA-212 functions as a tumor suppressor in non-small cell lung cancer.

Acetylcholinesterase expression is modulated in various types of tumor, which suggests it is associated with tumor development; however, the mechanism of acetylcholinesterase gene regulation in tumors remains unclear. Here, we report that acetylcholinesterase is aberrantly expressed in non-small cell lung cancer and is an evolutionarily conserved functional target of miR-212. Acetylcholinesterase expression was negatively regulated by miR-212 in vitro and was inversely correlated with miR-212 expression in vivo. In addition, acetylcholinesterase levels were increased, and miR-212 levels decreased, in non-small cell lung cancer cells during cisplatin-induced apoptosis. We further determined that acetylcholinesterase acted as a pro-apoptotic gene in non-small cell lung cells; and attenuated the growth of xenografts in nude mice when upregulated. In contrast, elevated miR-212 levels preserved the protective effect of acetylcholinesterase silencing by RNA interference against cisplatin-induced apoptosis, whereas restoration of miR-212-resistant synaptic acetylcholinesterase expression inhibited the miR-212 anti-apoptotic function. The results demonstrated that miR-212 exerted an anti-apoptotic effect through direct repression of synaptic acetylcholinesterase expression in non-small cell lung cancer cells. Taken together, our study revealed that synaptic acetylcholinesterase may be a tumor suppressor and is modulated by miR-212 in non-small cell lung cancer.