Effects of lysyl oxidase down-regulation on invasion, migration and E-cadherin protein expression of hypoxic lung cancer cells

Abstract

To observe the effects of lysyl oxidase (LOX) down-regulation on invasion, migration and epithelial-mesenchymal transition phenotype molecule E-cadherin protein expression, induced by hypoxia in lung cancer NCI-H460 cells. Small interfering RNA against human LOX gene (LOX siRNA) was used to transfect lung cancer cells under normoxia (19%O2). After a 24 h incubation, the cells were plated for 24 h in hypoxic incubator (0.5%O2). Real-time polymerase chain reaction (PCR) was performed to detect the LOX mRNA expression. The protein levels of LOX and E-cadherin were determined by Western blot. And invasion and migration capacities were detected by transwell chamber. Compared with NCI-H460 cells under normoxia (set to 1), hypoxia increased to the levels of LOX mRNA and protein expression up to 26.04 ± 1.78 and 5.57 ± 1.27 respectively (both P < 0.05). Compared with control siRNA group (set to 1), LOX mRNA and protein expression after LOX siRNA transfection were 0.24 ± 0.03 and 0.29 ± 0.03 respectively, cellular invasive and migratory capacities were 0.57 ± 0.03 and 0.49 ± 0.02 respectively, the protein expression of E-cadherin was 2.17 ± 0.21 (all P < 0.05). LOX down-regulation reduces invasion and migration potentials of hypoxic human lung cancer cell and potentiates the protein expression of E-cadherin.