MicroRNA-103 regulates tumorigenesis in colorectal cancer by targeting ZO-1

Given the emerging role of microRNAs (miRs) in cancer progression, the present study investigated the role and underlying mechanism of miR-103 in colorectal cancer (CRC). Reverse transcription-quantitative polymerase chain reaction was conducted to quantify the expression levels of miR-103 in clinical specimens and cell lines. The role of miR-103 in CRC was examined using MTT, colony formation and transwell assays. In addition, a luciferase reporter assay was used to confirm an associated between the 3′ untranslated region of zonula occuldens-1 (ZO-1) and miR-103. The results demonstrated that miR-103 was upregulated in CRC. Overexpression of miR-103 promoted CRC cell proliferation and migration in vitro, whereas downregulation of miR-103 inhibited cell proliferation and migration. ZO-1 was identified as a direct target of miR-103, revealing its expression to be inversely correlated with miR-103 expression in CRC samples. In conclusion, the present study revealed that miR-103 has strong tumor-promoting effects via of targeting ZO-1 in CRC and has potential development of miRNA-based targeted approaches for the treatment of CRC.