水通道蛋白4调控恶性胶质瘤细胞凋亡的研究

Objective To investigate the effects of apuaporin 4 (AQP4) on apoposis of LN229 glioblastoma cells by AQP4 small RNA interference (siRNA) technology and the molecular mechanism.Methods AQP4 expression was knocked down in LN229 glioblastoma cells by AQP4 siRNA (scr/LN229 and siAQP4/LN229 cells). The expression level of AQP4 protein in LN229 cells was detected by Western blotting. Stable clones were used to measure cells survival ratio (6 days) by methyl thiazol tetrazolium ( MTT) assay. Flow cytometry (FCM) was used to examine the content of cytochrome C in siAQP4/LN229 and scr/LN229. Western blotting was used to measure the levels of cytochrome C, bcl-2 and Bad. Nu/Nu mice were subcutaneously injected with siAQP4/LN229 and scr/LN229 cells to study the growth of tumor in the two groups (20 mice in each group). Results Western blotting showed that the expression of AQP4 was decreased significantly; MTT assay suggested that the survival ratio was decreased with deficiency of AQP4: the survival ratio of scr/LN229 was (587.00 ±4.68)%, and the ratio of siAQP4/N229 was (317. 00 ± 26. 30)% at sixth day (P＜0. 05). The mean fluorescence density of cytochrome C in scr/LN229 and siAQP4/LN229 by FCM was (57.2 ± 16.64) and (468.8 ±46.9) respectively (P＜0.05). The relative intensity of cytochrome C and Bad in siAQP4/N229 cells was ( 1. 62 ±0. 16) and (1. 30 ±0. 24) respectively, and that in scr/LN229 cells was (0. 83 ±0. 29) and (0. 56 ±0. 21) respectively (P＜0. 05). The intensity of bcl-2 in siAQP4/N229 cells (0.53 ±0.03) was decreased compared to scr/LN229 cells (0. 73 ± 0. 12) ( P ＜ 0. 05). The subcutaneous mouse xenograft model showed that the mean tumor volume of scr/LN229 group was (402. 67 ±34. 27) mm3, and that of siAQP4/N229 group was (65. 15 ±32. 12) mm3 at the 6th week. Conclusion AQP4 can regulate apoptosis of glioblastoma cell line LN229, which may be related with the release of cytocherome C, Bad and bcl-2.

Effect of apuaporin 4 on apoptosis of human glioblastoma cells