Hospital for Children and Adolescents, University of Leipzig, Leipzig, Germany.
Gastroenterology. 2012 May;142(5):1093-1096.e6. doi: 10.1053/j.gastro.2012.01.011. Epub 2012 Jan 20.
The Phosphatase And Tensin Homolog Deleted On Chromosome 10 (PTEN) regulates the phosphoinositol-3-kinase (PI3K)-AKT signaling pathway. In a series of 34 patients with PTEN mutations, we described gastrointestinal lymphoid hyperplasia, extensive hyperplastic tonsils, thymus hyperplasia, autoimmune lymphocytic thyroiditis, autoimmune hemolytic anemia, and colitis. Functional analysis of the gastrointestinal mucosa-associated lymphoid tissue revealed increased signaling via the PI3K-AKT pathway, including phosphorylation of S6 and increased cell proliferation, but also reduced apoptosis of CD20(+)CD10(+) B cells. Reduced activity of PTEN therefore affects homeostasis of human germinal center B cells by increasing PI3K-AKT signaling via mammalian target of rapamycin as well as antiapoptotic signals.
磷酸酶和张力蛋白同源物缺失于第 10 号染色体（PTEN）调节磷酸肌醇-3-激酶（PI3K）-AKT 信号通路。在一系列 34 名患有 PTEN 突变的患者中，我们描述了胃肠道淋巴组织增生、广泛的扁桃体增生、胸腺增生、自身免疫性淋巴细胞性甲状腺炎、自身免疫性溶血性贫血和结肠炎。对胃肠黏膜相关淋巴组织的功能分析显示，PI3K-AKT 通路的信号传递增加，包括 S6 的磷酸化和细胞增殖增加，但 CD20(+)CD10(+)B 细胞的凋亡减少。因此，PTEN 的活性降低通过增加雷帕霉素靶蛋白以及抗凋亡信号的 PI3K-AKT 信号，影响人类生发中心 B 细胞的体内平衡。
