Liver kinase B1 gene enhances radiosensitivity of lung cancer H460 cells: an in vivo study

Abstract

Objective To investigate the effect of liver kinase B1(LKB1) on the radiosensitivity of subcutaneous xenograft tumor of lung cancer H460 cells in nude mice. Methods Human lung cancer H460 cells were implanted into female nude mice (BALB/c-nu) to establish a subcutaneous xenograft tumor model of lung cancer. A total of 24 female nude mice in which the model was successfully established were equally and randomly divided into four groups: pEGFP-Ctrl plasmid (empty vector plasmid) group, irradiation (IR)+ pEGFP-Ctrl plasmid group, pEGFP-LKB1 plasmid (overexpressing LKB1) group, and IR+ pEGFP-LKB1 plasmid group. The growth of xenograft tumors was observed and the tumor inhibition rate and enhancement factor (EF) were calculated. The expression of LKB1 in each group was measured by immunohistochemistry and Western blot to analyze the relationship between LKB1 and radiosensitivity. Results Compared with the pEGFP-Ctrl plasmid group, the IR+ pEGFP-Ctrl plasmid group, pEGFP-LKB1 plasmid group, and IR+ pEGFP-LKB1 plasmid group showed varying degrees of inhibition of tumor growth, particularly in the IR+ pEGFP-LKB1 plasmid group, and the tumor inhibition rates were 31.30%, 14.78%, and 43.48%, respectively. The EF of LKB1 in the IR+ pEGFP-LKB1 plasmid group was 1.18.The immunohistochemistry and Western blot showed that LKB1 could be effectively expressed in the pEGFP-LKB1 plasmid group and IR+ pEGFP-LKB1 plasmid group, but not in the other two groups. Conclusions The subcutaneous xenograft tumor model of human lung cancer H460 cells has been successfully established in nude mice. LKB1 has a radiosensitizing effect on the subcutaneous xenograft tumor of lung cancer H460 cells in nude mice. Key words: Lung cancer cell line; Liver kinase B1; Radiosensitivity; Xenograft