Cancer Sci. 2021 Jul 26.
BACKGROUND/AIMS: Insulin-like growth factor 2 (IGF2) mRNA-binding protein 2 (IGF2BP2) is a post-transcriptional regulatory factor that has been implicated in the development of cancer. Herein, this study was performed to examine the possible role of of IGF2BP2 in colorectal cancer (CRC) and its underlying mechanism.
METHODS: First, the expression patterns of IGF2BP2, YAP, and ErbB2 were detected in clinical tissue samples from CRC patients and CRC cell lines. In addition, cell proliferation, migration, invasion and apoptosis were measured and recorded. Enrichment of TEAD4 in the ErbB2 promoter region was measured. Furthermore, IGF2BP2 binding to m6A-modified YAP mRNA was determined using Me-RIP assay with anti-IGF2BP2 antibody. Lastly, a xenograft tumor mouse model was established to substantiate in vitro findings.
RESULTS: IGF2BP2, YAP, and ErbB2 were highly-expressed in CRC tissues and cell lines. In addition, IGF2BP2 was found to be bind to m6A-modified YAP mRNA and increased its stability in CRC cells, thus augmenting the proliferation, migration and invasion of CRC cells while reducing their apoptosis. Meanwhile, YAP regulated ErbB2 expression by promoting TEAD4 enrichment in the ErbB2 promoter region. IGF2BP2 up-regulated ErbB2 by stabilizing YAP expression, and thus promoted proliferation, migration and invasion of CRC cells while attenuating their apoptosis. Also, IGF2BP2 promoted tumor formation in nude mice by regulating the YAP/ErbB2 axis.
CONCLUSION: Overall, our findings indicated that IGF2BP2 may bind to m6A-modified YAP mRNA to promote YAP stability and activate the expression of ErbB2, thus facilitating the progression of CRC.
Keywords: Apoptosis; Colorectal cancer; ErbB2; IGF2BP2; Invasion; Migration; Proliferation; YAP; m6A