Xiao Ming, Tang Yi, Chen Wen-Wen, Wang Ya-Lan, Yang Lian, Li Xian, Song Guang-Lin, Kuang Jing
Department of Pathology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, No. 1 Yixueyuan Rd, Chongqing, 400016, China.
Tumour Biol. 2016 Feb;37(2):2353-63. doi: 10.1007/s13277-015-4058-y. Epub 2015 Sep 15.
The influence of the most important classical mono-ADP-ribosyltransferase, arginine ADP-ribosyltransferase 1 (Art1), on survival and apoptosis of colon carcinoma cells and the potential mechanisms have been partly discussed in our previous study but still need to be further studied. In this present study, Art1 of colon carcinoma CT26 cells was silenced with lentiviral vector-mediated short hairpin RNA (shRNA) or overexpressed with lentiviral vector-mediated complementary DNA (cDNA) and allograft transplant tumors are established in Balb/c mice. We verified Art1 knockdown increases apoptosis of CT26 cells transplant tumor; Art1 overexpression acts oppositely. Accordingly, growth of transplant tumors is inhibited in Art1 knockdown transplant tumors and increases in Art1 overexpression transplant tumors. Furthermore, activity of Akt and Erk cell signal pathways and expression of an apoptosis biomarker, βIII-tubulin (Tubb3), decrease when Art1 was silenced and increase when Art1 was overexpressed. Inhibiting Akt pathway or Erk pathway both downregulates expression of Tubb3 on protein and messenger RNA (mRNA) level, indicating that Tubb3 could be regulated by both Akt and Erk pathways, and plays a role in the influence of Art1 on apoptosis of Balb/c mice allograft transplant tumor. We also demonstrated that Bcl-2 family is not the responsible downstream factor of the Erk pathway in colon carcinoma cells which is undergoing apoptosis. These findings enrich the molecular mechanism for the function of Art1 in colon carcinoma and provide a complementary support for Art1 to be a potential therapeutic target of the treatment of this kind of malignant tumor.
最重要的经典单 ADP 核糖基转移酶，精氨酸 ADP 核糖基转移酶 1（Art1）对结肠癌细胞存活和凋亡的影响及其潜在机制在我们之前的研究中已有部分探讨，但仍需进一步研究。在本研究中，通过慢病毒载体介导的短发夹 RNA（shRNA）使结肠癌 CT26 细胞的 Art1 沉默，或通过慢病毒载体介导的互补 DNA（cDNA）使其过表达，并在 Balb/c 小鼠中建立同种异体移植肿瘤。我们证实 Art1 敲低会增加 CT26 细胞移植瘤的凋亡；Art1 过表达则起相反作用。相应地，Art1 敲低的移植瘤中移植瘤生长受到抑制，而 Art1 过表达的移植瘤中移植瘤生长增加。此外，当 Art1 沉默时，Akt 和 Erk 细胞信号通路的活性以及凋亡生物标志物βIII -微管蛋白（Tubb3）的表达降低，当 Art1 过表达时则增加。抑制 Akt 通路或 Erk 通路均会在蛋白质和信使核糖核酸（mRNA）水平下调 Tubb3 的表达，表明 Tubb3 可受 Akt 和 Erk 通路调控，并在 Art1 对 Balb/c 小鼠同种异体移植瘤凋亡的影响中发挥作用。我们还证明在正在经历凋亡的结肠癌细胞中，Bcl - 2 家族不是 Erk 通路的下游责任因子。这些发现丰富了 Art1 在结肠癌中功能的分子机制，并为 Art1 成为这类恶性肿瘤治疗的潜在靶点提供了补充支持。
