Let‑7i‑5p inhibits the proliferation and metastasis of colon cancer cells by targeting kallikrein‑related peptidase 6.

Colorectal cancer is one of the most common types of malignancies worldwide, and as it is often diagnosed at an advanced stage, it is a serious threat to human health. MicroRNAs are important regulators of the growth and metastasis of colon cancer (CC). In the present study, the results demonstrated that kallikrein‑related peptidase 6 (KLK6) plays a critical role in suppressing colon carcinoma progression. To further investigate whether microRNAs affect the impact of KLK6, a bioinformatics approach was employed, which indicated that let‑7i‑5p may directly target KLK6. Furthermore, the expression level of let‑7i‑5p was significantly negatively correlated with the expression of KLK6 at the mRNA and protein levels in CC. Functionally, overexpression of let‑7i‑5p inhibited the proliferation and invasion of CC cells, and suppressed the growth of CC in vitro. The luciferase reporter assays revealed that let‑7i‑5p targeted the KLK6 3'‑untranslated region. Collectively, these results indicated that let‑7i‑5p inhibited the proliferation and metastasis of CC cells by targeting KLK6, thereby blocking the cell cycle and promoting apoptosis in colon cells. Therefore, the present study revealed that the let‑7i‑5p/KLK6 axis may be a potential target for new therapeutic strategies to treat colon tumors.