Xu Xiulian, Yuan Huayan, Lv Qijun, Wu Zhenjiang, Fan Wenhai, Liu Jianjun
Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, China.
North Sichuan Medical College, Nanchong, Sichuan, China.
Cell Biochem Biophys. 2025 Jun;83(2):2289-2299. doi: 10.1007/s12013-024-01641-x. Epub 2024 Dec 18.
To investigate the regulatory mechanism of indoleamine 2, 3-dioxygenase (IDO) in T lymphocyte differentiation and its role in promoting the growth of gastric cancer (GC) cells through the PI3K/Akt/mTOR pathway. GC cell lines (MFC and NCI-N87) and PBMC cells were co-cultured and IDO inhibitor 1-methyl-tryptophan (1-MT) was added. The proliferation was detected by CCK-8, the apoptosis was detected by flow cytometry, and the contents of TNF-α, IL-1β, IL-6, IL-8, and INF-γ were detected by ELISA. The expression levels of PI3K, p-PI3K, Akt, p-Akt, mTOR, and p-mTOR were tested using Western blot, and the proportion of CD4/CD8, CD4CD25Foxp3Treg cells was detected by flow cytometry. C57BL/6 mice were used to establish the MFC GC mouse model and treated with 1-MT. The changes in body weight and tumor diameter were measured. Ki-67, CD4, CD8, and CD25 expressions were detected by immunohistochemistry. IDO promoted the proliferation of MFC and NCI-N87 cells, inhibited apoptosis, and decreased the levels of TNF-α, IL-1β, IL-6, IL-8, and INF-γ in the supernatant after co-culture with BPMC. The expressions of p-AKT, p-mTOR, and p-PI3K increased after 1-MT treatment. The proportion of CD4/CD8 cells was increased and the proportion of Treg cells was decreased in PBMC cells after the addition of 1-MT. Overexpression of IDO suppressed T cells differentiation by inhibiting the PI3K/Akt/mTOR pathway. In vivo, 1-MT treatment reduced the tumor size and weight, increased CD4 and CD8 positive area proportion, and decreased Ki-67 and CD25 positive area proportion. Co-culture of GC cells and immune cells promotes the proliferation of GC cells and inhibits apoptosis, which can be reversed by 1-MT. IDO may suppress the proliferation of T lymphocyte through inhibiting the PI3K/Akt/mTOR signaling pathway. This provides new evidence for the potential of exploiting IDO inhibitors for GC treatment.
探讨吲哚胺2,3-双加氧酶（IDO）在T淋巴细胞分化中的调控机制及其通过PI3K/Akt/mTOR途径促进胃癌（GC）细胞生长的作用。将GC细胞系（MFC和NCI-N87）与外周血单个核细胞（PBMC）共培养，并添加IDO抑制剂1-甲基色氨酸（1-MT）。采用CCK-8检测细胞增殖，流式细胞术检测细胞凋亡，ELISA检测上清液中TNF-α、IL-1β、IL-6、IL-8和INF-γ的含量。用蛋白质免疫印迹法检测PI3K、p-PI3K、Akt、p-Akt、mTOR和p-mTOR的表达水平，流式细胞术检测CD4/CD8、CD4⁺CD25⁺Foxp3⁺调节性T细胞（Treg）的比例。用C57BL/6小鼠建立MFC胃癌小鼠模型并给予1-MT治疗。测量体重和肿瘤直径的变化。采用免疫组织化学法检测Ki-67、CD4、CD8和CD25的表达。IDO促进MFC和NCI-N87细胞增殖，抑制细胞凋亡，并降低与BPMC共培养后上清液中TNF-α、IL-1β、IL-6、IL-8和INF-γ的水平。1-MT处理后p-AKT、p-mTOR和p-PI3K的表达增加。添加1-MT后PBMC细胞中CD4/CD8细胞比例增加，Treg细胞比例降低。IDO过表达通过抑制PI3K/Akt/mTOR途径抑制T细胞分化。在体内，1-MT治疗可减小肿瘤大小和重量，增加CD4和CD8阳性面积比例，降低Ki-67和CD25阳性面积比例。GC细胞与免疫细胞共培养促进GC细胞增殖并抑制细胞凋亡，1-MT可逆转这一过程。IDO可能通过抑制PI3K/Akt/mTOR信号通路抑制T淋巴细胞增殖。这为开发IDO抑制剂用于GC治疗的潜力提供了新证据。
