The role of ATP8A1 in non-small cell lung cancer.

The study objective was to investigate the expression of ATP8A1 in non-small cell lung cancer (NSCLC) and to discover the role of ATP8A1 in the carcinogenesis of NSCLC. We collected 25 cases of tumor tissues and the adjacent normal tissues from surgeries of NSCLC patients in our hospital, among which 15 cases were found with lymph node metastasis while the other 10 were not. Immunohistochemical staining was performed to compare the expression level of TAP8A1 protein in NSCLC tissues with or without lymph node metastasis and the adjacent normal tissues. Transwell and scratch assay were used to test the invasion/migration capacity of different types of NSCLC. PCR and Western Blots were performed to detect the expression of ATP8A1 and epithelial-mesenchymal transition (EMT) markers in different cells. The percentage of ATP8A1 positive cells was (39.2±8.6)% in NSCLC tissues without lymph node metastasis, which was significantly lower than that in NSCLC tissues with lymph node metastasis ((74.7±11.0)%, P<0.05) as wells as remarkably higher than that in adjacent normal tissues with no ATP8A1 expression (P<0.05). When compared with normal H1299 cells, the invasion ability of ATP8A1 knock-down cells (si-H1299) was down-regulated by (31.2±5.7)%, the migration ability was down-regulated by (23.4±7.1)%, and the gene expression level of MMP and Vimentin was significantly reduced (P<0.05) while the expression of E-cadherin was remarkably increased (P<0.05). ATP8A1 was overexpressed in NSCLC tissues which promoted the expression of MMP-9 and Vimentin as well as suppressed the expression of E-cadherin thus resulting in the elevated invasion/migration ability of NSCLC cells.