Effects on human leukocyte antigen-G on proliferation and invasion of JEG-3 cell line

Abstract

To investigate the effect of human leukocyte antigen-G (HLA-G) on the growth and invasion of JEG-3 cell line and the role of HLA-G in the onset and development of pre-eclampsia. The experiment was composed of three groups: groups of transfection, negative control and blank control, which corresponded to groups of HLA-G siRNA transfection, negative siRNA transfection and no transfection. HLA-G overexpressed choriocarcinoma cell line JEG-3 was used. The role of HLA-G in JEG-3 cell monolayer was examined by RNA interference technology using HLA-G specific small interfering RNA (siRNA). Expression of HLA-G was detected by reverse transcriptase-polymerase chain reaction and western blot analysis. Changes of cell cycle, apoptosis, proliferation and invasion were respectively detected by methyl thiazolyl tetrazolium (MTT), flow cytometry assay and transwell test. (1) The mRNA and protein levels of HLA-G control group and blank control group were 0.0013 +/- 0.0014, 0.0163 +/- 0.0007 and 0.1923 +/- 0.0384, 0.2184 +/- 0.0153, respectively, which were both significantly different (P<0.05); the number of negative transfection group was 0.1606 +/- 0.0133 and 0.2020 +/- 0.0132, which had no significant difference compared with blank control group (P>0.05). (2) The integral absorbance (IA) values of the HLA-G transfection group and blank control group were 0.44 +/- 0.04 and 0.75 +/- 0.13 respectively, which was significantly different (P<0.01); the IA value of negative control group was 0.69 +/- 0.10, which was not significantly different compared with blank group (P>0.05). (3) The ratios of G2/M and S phase cells in transfection group were (10.9 +/- 2.2)% and (58.6 +/- 0.8)% respectively, significantly different compared with the blank control group [(15.4 +/- 1.9)% and (52.9 +/- 2.3)% respectively; P<0.01]. (4) The ratio of early apoptosis cells in transfection group [(14.5 +/- 2.7)%] was significantly increased compared with negative [(5.3 +/- 1.1)%] and blank control group [(4.7 +/- 0.6)% ; P<0.01]. (5) The invasion number of transfection group and blank control group were 121+/- 12 and 452 +/- 17 respectively, with a significant difference between them (P<0.01). HLA-G is probably involved in the onset of preeclampsia by regulating proliferation and invasion of trophoblast.