[Effects of a novel spermine oxidase inhibitor SI-4650 on proliferation and EMT of human ovarian cancer SKVO-3 cells].

Objective: To investigate the effects of SI-4650, a novel small molecule inhibitor of spermine oxidase (SMO), on the proliferation and epithelial mesenchymal transformation (EMT) of human ovarian cancer SKVO-3 cells as well as its underlying molecular mechanisms. Methods: SKVO-3 cells treated with 0 μmol/L SI-4650 were used as control group, SKVO-3 cells treated with 30, 60 μmol/L SI-4650 were used as experimental group. The effects of SI-4650 on the activity of SMO, the polyamine contents and the cellular reactive oxygen species (ROS) were detected. Cell proliferation, cell cycle and mitochondrial membrane potential change of SKVO-3 cells were tested. The effects of SI-4650 on apoptosis, migration and invasion were investigated. The effects of SI-4650 on Bax, Bcl-2, Caspase3, E-cadherin, N-cadherin, Vimentin, matrix metalloproteinase 2 ( MMP2) and MMP 9 expression levels in SKVO-3 cells were detected. Results: Comparison between blank control group and experimental groups,SI-4650 could improve the content of SI-4650 in SKVO-3 cells. SI-4650 could inhibit the activity of SMO (P＜0.01), reduce the ROS (P＜0.01)and polyamine content in SKVO-3 cells (P＜0.01). Treatment of SKVO-3 cells with SI-4650 inhibited the proliferation (the inhibition rate was 32.27% and 47.31% in experimental groups), caused S-phase cell cycle arrest (P＜0.01) and induced apoptosis (P＜0.01). The expressions of Bax and c-Caspase3 in SKVO-3 cells were increased (P＜0.01),the content of Bcl-2 was decreased (P＜0.01), and the mitochondrial membrane potential was decreased (P＜0.01), and the number of apoptotic cells was increased(31.41% and 43.51% in experimental groups). At the same time, SI-4650 could change the expression levels of EMT-related factors, increased the expression level of E-cad , decreased the expression levels of N-cad, Vimentin, MMP-2 and MMP-9, and inhibited the migration and invasion of SKVO-3 cells. Conclusion: SI-4650 can effectively inhibit proliferation, invasion and metastasis of human ovarian cancer SKVO-3 cells, and the mechanism may be related to its ability to depress the activity of SMO, interfere polyamine metabolism and induce cell cycle arrest, mitochondrial apoptosis and inhibit EMT. This study reveals potential application of SI-4650 in the treatment of ovarian cancer.目的: 研究新型精胺氧化酶(SMO)小分子抑制剂SI-4650对人卵巢癌SKVO-3细胞增殖和上皮细胞间质化影响及其分子机制。方法: 体外培养SKVO-3细胞,以未加药作为对照组,30、60 μmol/L SI-4650处理48 h细胞为实验组,每组设3个复孔,检测SI-4650对SKVO-3细胞内SMO的酶活性及多胺含量、酶促反应产物活性氧水平的影响,对细胞增值、周期、线粒体膜电位的作用,以及对细胞凋亡、侵袭和迁移能力的影响,同时检测凋亡相关蛋白Bax、Bcl-2、Caspase3以及上皮细胞间质化(EMT)相关蛋白E-Cad、N-Cad、Vimentin、MMP-2、MMP-9表达。结果: 与对照组相比,实验组SKVO-3细胞中SI-4650浓度增加,明显抑制SKVO-3细胞内SMO酶活性(P＜0.01)、减少SMO酶促反应产物活性氧水平(P＜0.01)、降低细胞内总多胺含量(P＜0.01)。SI-4650高效抑制SKVO-3细胞生长(P＜0.01),实验组细胞生长抑制率分别为32.27%、47.31%;将SKVO-3细胞阻滞在S期(P＜0.01),实验组细胞 Bax表达和Caspase3活化剪切增加,Bcl-2表达减少,线粒体膜电位下降,凋亡细胞比率增加至31.41%、43.51%;同时,实验组E-cad表达显著增加,N-cad、Vimentin表达均明显减少,合成分泌MMP-2、MMP-9减少,干扰了SKVO3细胞EMT进程,降低肿瘤细胞侵袭、迁移能力(P＜0.01)。结论: SI-4650对人卵巢癌SKVO-3 细胞具有杀伤和抑制肿瘤细胞侵袭、迁移的抗肿瘤活性,其机制可能与干扰多胺代谢、诱导细胞S周期阻滞和线粒体途径细胞凋亡以及干扰细胞EMT进程相关。.