Xue Lingli, Zeng Yan, Fang Chuan, Cheng Wei, Li Yadong
Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
Oncol Lett. 2020 Dec;20(6):340. doi: 10.3892/ol.2020.12203. Epub 2020 Oct 8.
Nitrotyrosine, a structural analogue of tyrosine, is present in cells in pathological conditions and is incorporated into tubulin to form tubulin tyrosine nitration, which disrupts the normal function of microtubules. There is limited research on the functional aspects of tubulin tyrosine nitration in different types of tumor. In the present study, the effect of tubulin tyrosine nitration and tubulin tyrosine ligase like 12 (TTLL12) on the proliferation of SCC-25 cells was investigated. TTLL12-overexpressing cell lines were constructed and used to assess the effect of tubulin tyrosine nitration and TTLL12 on the proliferation of SCC-25 cells via western blotting, immunofluorescent and MTT assays. An TTLL12-stably overexpressing SCC-25 cell line and the enzyme-linked immunosorbent assay were used to establish a novel experiment for screening anticancer drugs targeting tubulin tyrosine nitration by assessing its sensitivity, specificity and repeatability, and using it to find an effective drug. The results demonstrated that the proliferative rate of the control cells was notably inhibited in the presence of nitrotyrosine compared with that of TTLL12-overexpressing cells. The results of the MTT assay revealed that the proliferation of TTLL12-silenced cells was significantly inhibited compared with that of the control group. The sensitivity, specificity and repeatability of the experiment were positive. It was found that nocodazole could have better anticancer effect than paclitaxel. Taken together, the results of the present study suggest that TTLL12 enhances SCC-25 cell survival in the presence of nitrotyrosine by disrupting nitration of the tyrosine residues of tubulin, and tubulin tyrosine nitration may be developed for the basic research of anticancer drugs.
硝基酪氨酸是酪氨酸的结构类似物,在病理条件下存在于细胞中,并被整合到微管蛋白中形成微管蛋白酪氨酸硝化,这会破坏微管的正常功能。关于不同类型肿瘤中微管蛋白酪氨酸硝化的功能方面的研究有限。在本研究中,研究了微管蛋白酪氨酸硝化和微管蛋白酪氨酸连接酶样12(TTLL12)对SCC - 25细胞增殖的影响。构建了过表达TTLL12的细胞系,并通过蛋白质印迹、免疫荧光和MTT试验评估微管蛋白酪氨酸硝化和TTLL12对SCC - 25细胞增殖的影响。使用稳定过表达TTLL12的SCC - 25细胞系和酶联免疫吸附测定法,通过评估其敏感性、特异性和重复性,并利用其寻找有效药物,建立了一种用于筛选靶向微管蛋白酪氨酸硝化的抗癌药物的新实验。结果表明,与过表达TTLL12的细胞相比,在存在硝基酪氨酸的情况下,对照细胞的增殖速率受到显著抑制。MTT试验结果显示,与对照组相比,沉默TTLL12的细胞的增殖受到显著抑制。该实验的敏感性、特异性和重复性均为阳性。发现诺考达唑比紫杉醇具有更好的抗癌效果。综上所述,本研究结果表明,TTLL12通过破坏微管蛋白酪氨酸残基的硝化作用,在存在硝基酪氨酸的情况下增强SCC - 25细胞的存活,并且微管蛋白酪氨酸硝化可能用于抗癌药物的基础研究。