The role of lncRNA MALAT1 in bone metastasis in patients with non-small cell lung cancer.

lncRNA metastasis-associated lung adencarcinoma transcript 1 (MALAT1) plays an important role in the metastasis of lung cancer. Yet, its role in bone metastasis and the related mechanism remain unknown. The present study aimed to investigate the role of lncRNA MALAT1 in the bone metastasis of non-small cell lung cancer (NSCLC), including the expression pattern in tumor tissues, and the effect on the apoptosis, proliferation, migration and invasion of NSCLC cells. The expression level of MALAT1 in NSCLC tissues with/without bone metastasis and in NSCLC cell lines with (ACC-LC-319/bone2)/without (SPC‑A1) bone metastatic ability was determined with qRT-PCR and compared with t-test. si-MALAT1 was used to downregulate the expression of MALAT1 in ACC-LC-319/bone2 cells. The proliferation ability was assessed by MTT assay, and the apoptosis, migration, invasion and tumorigenesis in vivo were also assessed to detect the effect of MALAT1 expression on NSCLC cells. In conclusion, the present study found that MALAT1 was significantly highly expressed in NSCLC tissues with bone metastasis and in NSCLC cell lines with high bone metastatic ability (P<0.0001). Downregulation of MALAT1 expression significantly inhibited proliferation and induced cell apoptosis in comparing with the negative controls. Our results also revealed that MALAT1 significantly increased the migration, invasion and tumorigenesis in vivo, which suggests its important role in the bone metastasis of NSCLC.