Open AccessMiR‐30‐5p suppresses cell chemoresistance and stemness in colorectal cancer through USP 22/Wnt/β‐catenin signaling axis
Author(s) -
Jiang Shixiong,
Miao Dazhuang,
Wang Muhong,
Lv Jiachen,
Wang Yihui,
Tong Jinxue
Publication year - 2019
Publication title -
journal of cellular and molecular medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.44
H-Index - 130
eISSN - 1582-4934
pISSN - 1582-1838
DOI - 10.1111/jcmm.13968
Subject(s) - wnt signaling pathway , sox2 , colorectal cancer , cancer research , viability assay , cell growth , catenin , stem cell , hek 293 cells , microrna , lgr5 , cancer stem cell , signal transduction , klf4 , biology , western blot , cell culture , chemistry , cancer , microbiology and biotechnology , embryonic stem cell , genetics , gene
Abstract Colorectal cancer ( CRC ) remains both common and fatal, and its successful treatment is greatly limited by the development of stem cell‐like characteristics (stemness) and chemoresistance. MiR‐30‐5p has been shown to function as a tumor suppressor by targeting the Wnt/β‐catenin signaling pathway, but its activity in CRC has never been assessed. We hypothesized that miR‐30‐5p exerts anti‐oncogenic effects in CRC by regulating the USP 22/Wnt/β‐catenin signaling axis. In the present study, we demonstrate that tissues from CRC patients and human CRC cell lines show significantly decreased miR‐30‐5p family expression. After identifying the 3’ UTR of USP 22 as a potential binding site of miR‐30‐5p, we constructed a luciferase reporter containing the potential miR‐30‐5p binding site and measured the effects on USP 22 expression. Western blot assays showed that miR‐30‐5p decreased USP 22 protein expression in HEK 293 and Caco2 CRC cells. To evaluate the effects of miR‐30‐5p on CRC cell stemness, we isolated CD 133 + CRC cells (Caco2 and HCT 15). We then determined that, while miR‐30‐5p is normally decreased in CD 133 + CRC cells, miR‐30‐5p overexpression significantly reduces expression of stem cell markers CD 133 and Sox2, sphere formation, and cell proliferation. Similarly, we found that miR‐30‐5p expression is normally reduced in 5‐fluorouracil (5‐ FU ) resistant CRC cells, whereas miR‐30‐5p overexpression in 5‐ FU resistant cells reduces sphere formation and cell viability. Inhibition of miR‐30‐5p reversed the process. Finally, we determined that miR‐30‐5p attenuates the expression of Wnt/β‐catenin signaling target genes (Axin2 and MYC ), Wnt luciferase activity, and β‐catenin protein levels in CRC stem cells.