Long noncoding RNA NBAT1 inhibits autophagy via suppression of ATG7 in non-small cell lung cancer.

Autophagy is critical for the survival of cancer cells. It has been reported that long noncoding RNA (lncRNA) neuroblastoma associated transcript 1 (NBAT1) exerts as a tumor suppressor in some cancers. However, the role of NBAT1 in autophagy of non-small cell lung cancer (NSCLC) remains unknown. Here, it was reported that NBAT1 overexpression inhibited autophagy, while knockdown of NBAT1 induced autophagy in NSCLC cells. Further mechanistic study showed that NBAT1 interacted with PSMD10 and promoted its degradation, and then inhibited the occupancy of PSMD10 and HSF1 in the ATG7 promoter to suppress ATG7 transcription. A significantly negative correlation between NBAT1 and ATG7 levels was observed in NSCLC tissue. The prognoses of NSCLC patients with low expression of NBAT1 were much worse than those with high-level NBAT1. Moreover, NBAT1 negatively regulated cell viability, clonogenicity, and chemoresistance through inhibition of autophagy. Our findings suggest that the NBAT1-PSMD10-ATG7 axis may be an attractive strategy in NSCLC treatment by suppressing autophagy and chemoresistance.