Expression of death receptor 5 upreguleted by chloroquine enhances the sensitivity of Huh7 cells to tumor necrosis factor related apoptosis-inducing ligand

Abstract

Objective To explore the effect of chloroquine on death receptor 5 (DR5) expression of hepatocellular carcinoma Huh7 cells and cell proliferation and apoptosis induced by tumor necrosis factor related apoptosis-inducing ligand (TRAIL). Methods Huh7 cells were divided into four groups: the control group (1:1 000 dimethyl sulfoxide), TRAIL group (50 μg/L), chloroquine group (10 μmol/L) and TRAIL+ chloroquine group (TRAIL 50 μg/L+ chloroquine 10 μmol/L). Thiazolyl blue tetrazolium bromide (MTT) assay was used to determine the proliferation activity of cells, immunofluorescence was used to detect the expression of DR5, 4', 6-diamidino-2-phenylindole (DAPI) staining was used to observe cell apoptosis and Western blot was used to detect the expression of cleaved poly ADP-ribose polymerase (PARP). Results TRAIL treatment could decrease Huh7 cells proliferation activity; when compared with the cell viability in the control group, the cell proliferation inhibition rate of chloroquine group, TRAIL group and TRAIL+ chloroquine group was (89±8)%, (53±10)% and (27±7)%, respectively; compared with TRAIL group alone, cell proliferation activity was decreased in TRAIL+ chloroquine group (t= 3.922, P= 0.017). The expression of DR5 was upregulated in chloroquine group, and the cell apoptosis signaling was activated in TRAIL+ chloroquine group. The cell apoptosis rate of TRAIL group and TRAIL+ chloroquine group was (10.0±2.3)% and (20.4±4.0)%, respectively, and there was a statistical difference (t= 3.894, P= 0.018). Conclusion Chloroquine can enhance the cell chemosensitivity to TRAIL treatment by upregulating the expression of DR5 in Huh7 cells. Key words: Carcinoma, hepatocellular; Chloroquine; Death receptor 5; Tumor necrosis factor-related apoptosis inducing ligand