信号转导和转录活化因子(signal transducers and activators of transcription, STATs)家族是一种存在于胞浆并在激活后能够转入核内与DNA结合的蛋白家族,具有信号转导和转录调控双重功能[5]。STATs蛋白广泛表达于机体不同类型的细胞和组织中,参与细胞生长、分化、凋亡等多种生理功能的调控,并与炎症、肿瘤和免疫反应关系密切。STATs家族成员中,STAT3与肿瘤的关系最为密切[6~7]。
信号转导和转录活化因子(STAT3)是STATs家族的重要成员,已被认为是一种癌基因,与肿瘤的发生、发展有密切关系,其过度激活将导致细胞的异常增殖和凋亡障碍,促进肿瘤细胞的形成[11~13]。STATs家族是一种存在于细胞浆并在激活后能够转入核内与DNA结合的独特的蛋白家族,它与酪氨酸磷酸化信号通道偶联,发挥信号转导和转录调控的作用[14]。JAK/sTAT代表的是一条极其快速的从细胞外到细胞核的信号转导通路。近年来发现JAK/sTAT途径的激活,特别是STAT3的激活,对于细胞的生长、增殖和转化产生重要影响。已有研究证实STAT3的酪氨酸磷酸化,即信号依赖的活化形式,在多种肿瘤中普遍存在,并在某些肿瘤中发挥重要作用[15]。信号转导子和转录激活子3( signal transducerand activator of transcription 3,STAT3)是一种存在于细胞浆与酪氨酸磷酸化信号通道偶联的双功能蛋白。STAT3过度激活将导致细胞的异常增殖和凋亡障碍,促进肿瘤的形成、发展。其致癌机制为促进细胞增殖、抑制细胞凋亡、促血管生成而加快转移[16~19]。
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