TENT5B上调PRKAA2表达促进胃癌铁死亡的作用与机制研究

The role and mechanism of TENT5B in upregulating PRKAA2 expression to promote ferroptosis in gastric cancer

摘要:

背景与目的 胃癌是全球高发且预后不良的恶性肿瘤，现有治疗手段疗效有限。铁死亡作为一种新型细胞死亡方式，在肿瘤治疗中具有重要潜力。末端核苷酸转移酶5B（TENT5B）在多种肿瘤中低表达，但其在胃癌中的作用尚未明确。本研究旨在探讨TENT5B在胃癌中的表达特征及其通过调控铁死亡抑制肿瘤进展的机制。方法 通过TCGA和GEO数据库分析TENT5B在胃癌中的表达情况，并采用qRT-PCR和Western blot检测其在胃癌组织及细胞中的表达水平；利用CCK-8、克隆形成、划痕愈合和Transwell实验评估TENT5B过表达对胃癌细胞增殖和迁移的影响；通过细胞活力、脂质活性氧化物和丙二醛水平分析铁死亡情况；结合生物信息学、mRNA稳定性检测和功能挽救实验探讨其分子机制；并通过小鼠皮下成瘤实验验证其体内作用。结果 TENT5B在胃癌组织和细胞中明显下调。过表达TENT5B可抑制胃癌细胞增殖和迁移，并促进铁死亡。机制研究表明，TENT5B通过增强PRKAA2 mRNA稳定性上调其表达，进而介导铁死亡的发生。体内实验进一步证实TENT5B过表达可抑制肿瘤生长并提高PRKAA2水平。结论 TENT5B作为潜在的抑癌基因，可通过增强PRKAA2 mRNA稳定性促进铁死亡，从而抑制胃癌进展。本研究为胃癌铁死亡靶向治疗提供了新的分子依据和潜在治疗策略。

Abstract:

Background and Aims Gastric cancer remains a common malignancy worldwide with a poor prognosis and limited response to current therapies. Ferroptosis, a novel form of regulated cell death, has emerged as a promising therapeutic target in cancer. Terminal nucleotidyltransferase 5B (TENT5B) is downregulated in various tumors, but its role in gastric cancer and ferroptosis remains unclear. This study aimed to investigate the expression pattern and biological function of TENT5B in gastric cancer and to elucidate its underlying mechanisms in regulating ferroptosis.Methods The expression of TENT5B in gastric cancer was analyzed using TCGA and GEO datasets, and further validated in gastric cancer tissues and cell lines by qRT-PCR and Western blotting. CCK-8, colony formation, wound healing, and Transwell assays were performed to evaluate the effects of TENT5B overexpression on cell proliferation and migration. Ferroptosis was assessed by measuring cell viability, lipid ROS, and MDA levels. Bioinformatics analysis, mRNA stability assays, and rescue experiments were conducted to explore the molecular mechanisms. A subcutaneous xenograft mouse model was used to validate the in vivo effects.Results TENT5B was significantly downregulated in gastric cancer tissues and cells. Overexpression of TENT5B inhibited cell proliferation and migration while promoting ferroptosis. Mechanistically, TENT5B enhanced PRKAA2 mRNA stability and upregulated its expression, thereby exerting tumor-suppressive effects. In vivo, TENT5B overexpression suppressed tumor growth and elevated PRKAA2 expression.Conclusion TENT5B functions as a tumor suppressor in gastric cancer by stabilizing PRKAA2 mRNA, promoting ferroptosis, and inhibiting cancer progression. These findings suggest that TENT5B may serve as a promising molecular target for ferroptosis-based therapeutic strategies in gastric cancer.