Department of Biochemical Sciences "A. Rossi Fanelli", Sapienza University of Rome, P. le Aldo Moro 5, 00185 Rome, Italy.
Int J Mol Sci. 2023 Aug 26;24(17):13279. doi: 10.3390/ijms241713279.
The protein disulfide isomerase A3 (PDIA3) is directly or indirectly involved in various physiopathological processes and participates in cancer initiation, progression and chemosensitivity. However, little is known about its involvement in glioblastoma. To obtain specific information, we performed cellular experiments in the T98G and U-87 MG glioblastoma cell lines to evaluate the role of PDIA3. The loss of PDIA3 functions, either through inhibition or silencing, reduced glioblastoma cells spreading by triggering cytotoxic phenomena. PDIA3 inhibition led to a redistribution of PDIA3, resulting in the formation of protein aggregates visualized through immunofluorescence staining. Concurrently, cell cycle progression underwent arrest at the G/S checkpoint. After PDIA3 inhibition, ROS-independent DNA damage and the activation of the repair system occurred, as evidenced by the phosphorylation of H2A.X and the overexpression of the Ku70 protein. We also demonstrated through a clonogenic assay that PDIA3 inhibition could increase the chemosensitivity of T98G and U-87 MG cells to the approved glioblastoma drug temozolomide (TMZ). Overall, PDIA3 inhibition induced cytotoxic effects in the analyzed glioblastoma cell lines. Although further in vivo studies are needed, the results suggested PDIA3 as a novel therapeutic target that could also be included in already approved therapies.
蛋白质二硫键异构酶 A3（PDIA3）直接或间接地参与各种生理病理过程，并参与癌症的发生、发展和化疗敏感性。然而，关于其在神经胶质瘤中的作用知之甚少。为了获得具体信息，我们在 T98G 和 U-87 MG 神经胶质瘤细胞系中进行了细胞实验，以评估 PDIA3 的作用。通过抑制或沉默 PDIA3 的功能，减少神经胶质瘤细胞的扩散，触发细胞毒性现象。PDIA3 抑制导致 PDIA3 的重新分布，导致通过免疫荧光染色可视化的蛋白质聚集体的形成。同时，细胞周期进程在 G/S 检查点停滞。PDIA3 抑制后，发生 ROS 非依赖性 DNA 损伤和修复系统的激活，这表现为 H2A.X 的磷酸化和 Ku70 蛋白的过表达。我们还通过集落形成实验证明，PDIA3 抑制可以增加 T98G 和 U-87 MG 细胞对已批准的神经胶质瘤药物替莫唑胺（TMZ）的化疗敏感性。总体而言，PDIA3 抑制在分析的神经胶质瘤细胞系中诱导细胞毒性作用。尽管还需要进一步的体内研究，但结果表明 PDIA3 是一个新的治疗靶点，也可以包含在已批准的治疗方法中。
