SMYD3对氯化钴诱导T47D乳腺癌细胞缺氧的影响分析

Effects of SMYD3 on CoCl_2-induced Hypoxia in T47D Breast Cancer Cells

为了探究组蛋白甲基化酶SMYD3是否会对氯化钴(CoCl_2)诱导乳腺癌细胞缺氧损伤作用产生影响,采用MTT法和流式细胞术检测不同浓度的CoCl_2(0、50、100、200、400,μmol/L)给药24,h以及联合转染过表达质粒使SMYD3过表达后对T47D细胞的增殖及细胞周期的影响;实时荧光定量PCR法(Real-time PCR)检测其对SMYD3转录表达的影响情况.MTT和流式细胞术结果显示:CoCl_2可剂量依赖性地对T47D乳腺癌细胞的增殖产生抑制作用(P<0.01),并诱导产生G0/G1期细胞周期阻滞(P<0.05).CoCl_2可以抑制SMYD3的转录(P<0.01).利用siRNA抑制内源性SMYD3表达后同样可诱导细胞发生G0/G1期阻滞(P<0.05),而转染外源质粒使SMYD3过表达则可明显拮抗CoCl_2所诱导的G0/G1期阻滞及对细胞的杀伤作用.CoCl_2对T47D细胞的周期调控作用可能与抑制SMYD3的表达有关,SMYD3的过表达可提升肿瘤细胞在缺氧环境下的存活能力.

This research investigated whether histone methylase SMYD3 could affect hypoxia induced by cobalt chloride(CoCl2)in breast cancer cells.Effects of different concentration of CoCl2(0,50,100,200,400μmol/L)for 24 h and cotransfection of overexpression plasmid on the proliferation and cell cycle of T47D cells after overexpression of SMYD3 were determined with MTT and Flow Cytometry.The effect of CoCl2 on the transcriptional level of SMYD3 was analyzed with Real-time PCR.CoCl2 significantly inhibited the proliferation of T47D cells(P<0.01),and induced cell arrest in the G0/G1 phase(P<0.05),which was consistent with the results of siRNAs-mediated absence of SMYD3(P<0.05).Furthermore,CoCl2 could down-regulate the transcription of SMYD3(P<0.01),and the overexpression of SMYD3 could abolish the effects of CoCl2 on the proliferation and cell cycle of T47D cells.The regulation of CoCl2 on cell cycle distribution was correlated with the transcription suppressing of SMYD3.Overexpression of SMYD3 might enhance the ability of cells to adapt to hypoxic environment.