Long non-coding RNA LSAMP-1 is down-regulated in non-small cell lung cancer and predicts a poor prognosis.

Background: Long noncoding RNAs (lncRNAs) are emerging as master regulators for gene expression and thus play a vital role in human tumorigenesis and progression. But the involvement of novel lncRNAs in non-small cell lung cancer (NSCLC) remains largely unelucidated.

Methods: A total of 170 NSCLC and their adjacent non-tumor tissues were enrolled to detect the expression of Lnc-LSAMP-1 by RT-qPCR. The effects of Lnc-LSAMP-1 on cell proliferation, migration, invasion and drug-sensitivity were determined by in vitro and in vivo experiments. The proteins that interact with Lnc-LSAMP-1were confirmed by RNA pull-down assay. RNA-sequencing were used to identify the potential targets of Lnc-LSAMP-1 in NSCLC.

Results: We found that Lnc-LSAMP-1 was significantly down-regulated in 170 cases of NSCLC tissues when compared to their adjacent non-cancerous tissues. Loss expression of Lnc-LSAMP-1 was notably correlated with unfavorable prognosis of NSCLC patients. The ectopic expression of Lnc-LSAMP-1 drastically inhibited lung cancer cell proliferation, viability, invasion and migration ability, arrested cell cycle and facilitated apoptosis. Chemotherapy sensitization experiments showed that over-expressed Lnc-LSAMP-1 enhanced the inhibition of cell proliferation induced by TKI. Mechanistically, Lnc-LSAMP-1-LSAMP formed a complex which could protect the degradation of LSAMP gene, and thus exerted crucial roles in NSCLC progression and TKI targeted treatment.

Conclusions: Consequently, our findings highlight the function and prognostic value of Lnc-LSAMP-1 in NSCLC and provide potential novel therapeutic targets and prognostic biomarkers for patients with NSCLC.