Xin Ma1, Donglai Shen1, Hongzhao Li1, Yu Zhang1, Xiangjun Lv1, Qingbo Huang1, Yu Gao1, Xintao Li1, Liangyou Gu1, Shaoxi Xiu1, Xu Bao2, Junyao Duan2, Xu Zhang3. 1. State Key Laboratory of Kidney Diseases, Department of Urology, Chinese People's Liberation Army Medical School, Chinese People's Liberation Army General Hospital, Beijing, P.R. China. 2. State Key Laboratory of Kidney Diseases, Department of Urology, Chinese People's Liberation Army Medical School, Chinese People's Liberation Army General Hospital, Beijing, P.R. China; Medical School, Nankai University, Tianjin, P.R. China. 3. State Key Laboratory of Kidney Diseases, Department of Urology, Chinese People's Liberation Army Medical School, Chinese People's Liberation Army General Hospital, Beijing, P.R. China. Electronic address: xzhang@foxmail.com.
Abstract
OBJECTIVES: The von Hippel-Lindau (VHL) gene acts as a tumor suppressor in most clear cell renal cell carcinomas (ccRCCs). Tumor growth in ccRCCs relies on many factors that result from the loss of VHL. This study aims to identify new microRNAs with therapeutic potential for VHL-inactivated ccRCCs. MATERIALS AND METHODS: We used 786O, A498 (VHL inactivated), and Caki-1 (VHL intact) ccRCC cell lines and 40 ccRCC samples and their adjacent nontumor tissues to measure the expression of microRNA-185 (miR-185) by real-time quantitative polymerase chain reaction. Overexpression or knockdown of VEGFA expression in renal cancer cells was fulfilled by transfecting expression plasmids or small interfering RNAs. Overexpression of miR-185 in ccRCC cell lines was fulfilled by transfecting chemically synthesized miR-185 mimics. The effects of miR-185 on ccRCC cell lines were detected by MTS assay, colony formation assay, and flow cytometric analysis. RESULTS: Compared with adjacent nontumor renal tissues, miR-185 expression levels decreased significantly in ccRCC tissues. The expression of miR-185 had a negative correlation with tumor size, Fuhrman grade, and TNM staging. Luciferase assay showed that VEGFA was a direct target gene of miR-185. The overexpression of miR-185 significantly inhibited cell proliferation and induced cell apoptosis by down-regulating VEGFA expression in VHL-inactivated ccRCC cells. CONCLUSIONS: Our results suggest that the miR-185, as a tumor suppressor, plays a pivotal role by inhibiting VEGFA in VHL-inactivated ccRCC.
OBJECTIVES: The von Hippel-Lindau (VHL) gene acts as a tumor suppressor in most clear cell renal cell carcinomas (ccRCCs). Tumor growth in ccRCCs relies on many factors that result from the loss of VHL. This study aims to identify new microRNAs with therapeutic potential for VHL-inactivated ccRCCs. MATERIALS AND METHODS: We used 786O, A498 (VHL inactivated), and Caki-1 (VHL intact) ccRCC cell lines and 40 ccRCC samples and their adjacent nontumor tissues to measure the expression of microRNA-185 (miR-185) by real-time quantitative polymerase chain reaction. Overexpression or knockdown of VEGFA expression in renal cancer cells was fulfilled by transfecting expression plasmids or small interfering RNAs. Overexpression of miR-185 in ccRCC cell lines was fulfilled by transfecting chemically synthesized miR-185 mimics. The effects of miR-185 on ccRCC cell lines were detected by MTS assay, colony formation assay, and flow cytometric analysis. RESULTS: Compared with adjacent nontumor renal tissues, miR-185 expression levels decreased significantly in ccRCC tissues. The expression of miR-185 had a negative correlation with tumor size, Fuhrman grade, and TNM staging. Luciferase assay showed that VEGFA was a direct target gene of miR-185. The overexpression of miR-185 significantly inhibited cell proliferation and induced cell apoptosis by down-regulating VEGFA expression in VHL-inactivated ccRCC cells. CONCLUSIONS: Our results suggest that the miR-185, as a tumor suppressor, plays a pivotal role by inhibiting VEGFA in VHL-inactivated ccRCC.
Authors: Duo Zhang; Heedoo Lee; Yong Cao; Charles S Dela Cruz; Yang Jin Journal: Am J Physiol Lung Cell Mol Physiol Date: 2016-01-08 Impact factor: 5.464