Experimental study of the effect of GOLPH3 on proliferation, apoptosis and radiosensitivity of OE33 esophageal cancer cell line

Abstract

Objective To evaluate the effect of GOLPH3 on the proliferation, apoptosis and radiosensitivity of OE33 esophageal cancer cell line. Methods The expression levels of GOLPH3 mRNA and protein in the esophageal cancer cells and normal esophageal epithelial cells were detected by qRT-PCR and Western blot, respectively. The OE33 esophageal cancer cells were transfected with GOLPH3 siRNA and subject to irradiation treatment simultaneously. The cell proliferation was detected by MTT assay. The cell apoptosis was detected by flow cytometry. The radiosensitivity was assessed by cell cloning test. The expression levels of cleaved Caspase-3, Bax and cleaved Caspase-9 protein levels were quantitatively measured by Western blot. Results The expression levels of GOLPH3 mRNA and protein in the esophageal cancer cells were significantly higher than those in the normal esophageal epithelial cells (both P<0.05). GOLPH3 siRNA could obviously down-regulate the expression levels of GOLPH3 mRNA and protein in the OE33 esophageal cancer cells. The proliferation activity of esophageal cancer cells was decreased, whereas the apoptosis rate was increased and the expression levels of cleaved Caspase-3, Bax and cleaved Caspase-9 were up-regulated after down-regulating the expression of GOLPH3 or irradiation treatment (all P<0.05). After down-regulating the expression of GOLPH3 in the esophageal cancer cells treated with irradiation, the cell proliferation activity was more significantly decreased, whereas the apoptosis rate was elevated and the expression levels of cleaved Caspase-3, Bax and cleaved Caspase-9 were more evidently up-regulated (all P<0.05). In the irradiated OE33 esophageal cancer cells after down-regulating the expression of GOLPH3, the radiosensitization ratio of the cells was 1.673. Conclusions GOLPH3 is highly expressed in the esophageal cancer cells. Down-regulating the expression of GOLPH3 can increase the radiosensitivity, induce the apoptosis and inhibit the proliferation of OE33 esophageal cancer cells. Key words: Esophageal cancer cell line; Apoptosis; Radiosensitivity; GOLPH3 gene