A novel long non-coding RNA LSAMP-1 is down-regulated in non-small cell lung cancer and predicts a poor prognosis

Abstract

Background There is very little known about how long non-coding RNAs (lncRNAs) are associated with membrane proteins in lung cancer. The limbic system-associated membrane protein ( LSAMP ) has been reported to play a tumor suppressor role in a variety of cancers.Methods We aimed to explore the lncRNA associated with LSAMP and explore its effects on lung cancer.Results We found that Lnc-LSAMP-1 was significantly down-regulated in 170 cases of lung tumor tissues when compared to the adjacent non-cancerous tissues (p<0.001). Our results indicated that low expression of Lnc-LSAMP-1 was significantly correlated with stage (TNM)(p=0.006), N status (p=0.009) and poor prognosis (p=0.004). Further investigation showed that overexpression of Lnc-LSAMP-1 significantly inhibited lung cancer cell proliferation, viability, invasion and migration ability, arrested cell cycle and facilitated apoptosis. Meanwhile, the expression of Lnc-LSAMP-1 is highly correlated with the expression of nearby tumor suppressor gene LSAMP in our samples (r=0.7074, p<0.001) and TCGA database (r=0.78, p<0.001). It was found that overexpression of Lnc-LSAMP-1 can slow down the degradation rate of LSAMP gene by mRNA protection experiments. By knocking down of LSAMP gene, it was found that overexpressed Lnc-LSAMP-1 cells showed a high proliferation rate. Chemotherapy sensitization experiments showed that overexpression of Lnc-LSAMP-1 enhanced TKI inhibition of lung cancer cell proliferation, which is probably related to affecting the prognosis of patients.Conclusions Consequently, the above data suggested that Lnc-LSAMP-1 functions as a tumor suppressor and provides a new potentially therapeutic and prognostic target for non-small cell lung cancer.