Songjia Guo1, Shuhua Shan2, Haili Wu2, Huiqiang Hao1, Zhuoyu Li3. 1. Nephrology Department, Shanxi Provincial People's Hospital, 29 Twin Pagoda Temple Street, Taiyuan, China. 2. School of Life Science, Shanxi University, 92 Wucheng Road, Taiyuan, Shanxi, China. 3. School of Life Science, Shanxi University, 92 Wucheng Road, Taiyuan, Shanxi, China. lzy@sxu.edu.cn.
Abstract
BACKGROUND: Nostoc commune Vauch. is a nitrogen-fixing blue-green algae that expresses a large number of active molecules with medicinal properties. Our previous study found that a water stress protein (WSP1) from N. commune and its recombinant counterpart (Re-WSP1) exhibited significant anti-colon cancer activity both in vitro and in vivo. This study is to investigate the effects of Re-WSP1 on proliferation of colon cancer cells and to elucidate the relevant mechanisms. METHODS: Real-time quantitative PCR was used to detect the expression of miR-539 in colon cancer HT-29 and DLD1 cells. Colon cancer cells were transfected with miR-539 mimics and negative controls, and cell proliferation were detected by CCK8 and clonogenic assays. The target gene of miR-539 was predicted, and the dual luciferase reporter gene experiment was used to verify the target gene. After colon cancer cells were transfected with miR-539 mimics or inhibitors, the expression of target gene β-catenin was detected by Western blot. miR-539 inhibitor confirmed cell proliferation. RESULTS: Re-WSP1 inhibited colon cancer cell growth in a dose-dependent manner. Re-WSP1 inhibited the expression of β-catenin, which was partly reversed by LiCl treatment. Quantitative PCR analysis showed that the expression of miR-539 was significantly upregulated after Re-WSP1 treatment. Moreover, miR-539 negatively regulated the expression of β-catenin by directly binding to the 3'UTR of β-catenin mRNA. The cell growth inhibition and the decrease in β-catenin expression induced by Re-WSP1 were significantly reversed by miR-539 inhibitor. CONCLUSION: Re-WSP1 suppresses colon cancer cell growth via the miR-539/β-catenin axis.
BACKGROUND: Nostoc commune Vauch. is a nitrogen-fixing blue-green algae that expresses a large number of active molecules with medicinal properties. Our previous study found that a water stress protein (WSP1) from N. commune and its recombinant counterpart (Re-WSP1) exhibited significant anti-colon cancer activity both in vitro and in vivo. This study is to investigate the effects of Re-WSP1 on proliferation of colon cancer cells and to elucidate the relevant mechanisms. METHODS: Real-time quantitative PCR was used to detect the expression of miR-539 in colon cancer HT-29 and DLD1 cells. Colon cancer cells were transfected with miR-539 mimics and negative controls, and cell proliferation were detected by CCK8 and clonogenic assays. The target gene of miR-539 was predicted, and the dual luciferase reporter gene experiment was used to verify the target gene. After colon cancer cells were transfected with miR-539 mimics or inhibitors, the expression of target gene β-catenin was detected by Western blot. miR-539 inhibitor confirmed cell proliferation. RESULTS: Re-WSP1 inhibited colon cancer cell growth in a dose-dependent manner. Re-WSP1 inhibited the expression of β-catenin, which was partly reversed by LiCl treatment. Quantitative PCR analysis showed that the expression of miR-539 was significantly upregulated after Re-WSP1 treatment. Moreover, miR-539 negatively regulated the expression of β-catenin by directly binding to the 3'UTR of β-catenin mRNA. The cell growth inhibition and the decrease in β-catenin expression induced by Re-WSP1 were significantly reversed by miR-539 inhibitor. CONCLUSION: Re-WSP1 suppresses colon cancer cell growth via the miR-539/β-catenin axis.