Heo Seung-Ho, Jeong Eui-Suk, Lee Kyoung-Sun, Seo Jin-Hee, Lee Woon-Kyu, Choi Yang-Kyu
Department of Laboratory Animal Medicine, College of Veterinary Medicine, Konkuk University, Seoul 143-701, Republic of Korea.
Laboratory Animal Center, Osong Medical Innovation Foundation, Chungbuk 363-951, Republic of Korea.
Oncol Rep. 2015 Apr;33(4):2037-44. doi: 10.3892/or.2015.3801. Epub 2015 Feb 13.
Liver cancer is the third most common cancer, and the incidence as well as the mortality rate of liver cancer are on the increase. There are many signaling pathways that are involved in hepatic tumorigenesis. One of these pathways, the transforming growth factor-β (TGF-β)/Smad pathway with KLF10, has been reported to suppress cellular proliferation in most cases. However, the actual functions of KLF10 in various pathophysiological conditions are still fragmentary and unclear. In the present study, the practical role of KLF10 in DEN-induced hepatic carcinogenesis, was elucidated using KLF10 null mice. In the necropsy and histopathological analysis, KLF10 KO mice exhibited lower tumor incidence and PCNA labeling indices than these values in the wild-type mice. Additional analyses revealed that the mRNA and protein levels of Smad3, TGF-β1, TGF-β RI and p15 were increased in the tumor tissues of the KLF10 KO mice, while those of cMyc and cyclin D1 were downregulated. The level of phospho-Smad3 was also significantly higher in the tumor tissues of the KLF10 KO mice. All together, the KLF10 KO condition may reinforce the TGF-β‑Smad signaling pathway and confer tumor-suppressor effects against chemically induced liver tumorigenesis.
肝癌是第三大常见癌症,其发病率和死亡率都在上升。有许多信号通路参与肝脏肿瘤的发生。其中一条通路,即与KLF10相关的转化生长因子-β(TGF-β)/Smad通路,在大多数情况下已被报道可抑制细胞增殖。然而,KLF10在各种病理生理条件下的实际功能仍然不完整且不清楚。在本研究中,使用KLF10基因敲除小鼠阐明了KLF10在二乙基亚硝胺(DEN)诱导的肝癌发生中的实际作用。在尸检和组织病理学分析中,KLF10基因敲除小鼠的肿瘤发生率和增殖细胞核抗原(PCNA)标记指数低于野生型小鼠。进一步分析表明,KLF10基因敲除小鼠肿瘤组织中Smad3、TGF-β1、TGF-β RI和p15的mRNA和蛋白水平升高,而cMyc和细胞周期蛋白D1的水平下调。KLF10基因敲除小鼠肿瘤组织中磷酸化Smad3的水平也显著更高。总体而言,KLF10基因敲除状态可能增强TGF-β-Smad信号通路,并对化学诱导的肝脏肿瘤发生具有肿瘤抑制作用。