ABSTRACT
@#磷脂酰肌醇蛋白聚糖3(glypican-3，GPC3)是一种锚定在细胞膜上的硫酸乙酰肝素(heparan sulfate，HS)蛋白多糖的家族成 员之一。GPC3激活经典的Wnt/β-连环蛋白(β-catenin)途径在肝癌(hepatocellular carcinoma，HCC)中表现出促癌基因的作用。尽 管GPC3在胎肝中含量丰富，在多种实体肿瘤中高表达，然而在成人正常组织中含量极少。选择靶点是肿瘤免疫治疗的关键。迄 今为止靶向GPC3的MRI、PET和近红外成像已被用于早期HCC检测。针对GPC3+实体瘤也已经开发了各种免疫治疗方案，一种 是基于抗GPC3抗体包括单克隆抗体、多肽疫苗、免疫毒素、双特异性抗体等，一种是靶向GPC3的CAR-T/NK疗法，其中部分已 进入I/II期临床试验。靶向GPC3有可能为实体瘤治疗提供新的工具。本文概述GPC3的结构、功能等生物学特性，介绍基于抗 GPC3抗体、CAR-T细胞开发的新策略，提供GPC3免疫疗法靶向实体瘤的证据。
ABSTRACT
Rhein is a primary anthraquinone found in the roots of a traditional Chinese herb, rhubarb, and has been shown to have some anticancer effects. The aim of the present study was to investigate the effect of rhein on the apoptosis of the human gastric cancer line SGC-7901 and to identify the mechanism involved. SGC-7901 cells were cultured and treated with rhein (0, 50, 100, 150, and 200 µM) for 24, 48, or 72 h. Relative cell viability assessed by the MTT assay after treatment was 100, 99, 85, 79, 63% for 24 h; 100, 98, 80, 51, 37% for 48 h, and 100, 97, 60, 36, 15% for 72 h, respectively. Cell apoptosis was detected with TUNEL staining and quantified with flow cytometry using annexin FITC-PI staining at 48 h after 100, 200 and 300 µm rhein. The percentage of apoptotic cells was 7.3, 21.9, 43.5%, respectively. We also measured the mRNA levels of caspase-3 and -9 using real-time PCR. Treatment with 100 µM rhein for 48 h significantly increased mRNA expression of caspase-3 and -9. The levels of apoptosis-related proteins including Bcl-2, Bax, Bcl-xL, and pro-caspase-3 were evaluated in rhein-treated cells. Rhein increased the Bax:Bcl-2 ratio but decreased the protein levels of Bcl-xL and pro-caspase-3. Moreover, rhein significantly increased the expression of cytochrome c and apoptotic protease activating factor 1, two critical components involved in mitochondrial pathway-mediated apoptosis. We conclude that rhein inhibits SGC-7901 proliferation by inducing apoptosis and this antitumor effect of rhein is mediated in part by an intrinsic mitochondrial pathway.