The roles and mechanisms of APOL1 in the development of colorectal cancer.

ABSTRACT

Background: Research has demonstrated that apolipoprotein L1 (APOL1) has a role in the emergence and progression of a number of malignant cancers. It is unclear, however, how APOL1 functions in colorectal cancer (CRC). In this study, we examined the possible molecular processes underlying APOL1's biological role in CRC. Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to identify APOL1 expression in patients with CRC and the cell line of cancer tissue. Following transfection of human colon carcinoma cells (HCT116) and human colon adenocarcinoma cells (SW1116) with sh-APOL1, the effects of APOL1 on the biological behavior of CRC cell lines were examined. In nude mice, the effect of APOL1 on tumor growth was noted. The protein interaction between APOL1 and RUNX1 was detected via coimmunoprecipitation. The expression of relevant proteins and cell biological behaviors were examined to confirm the APOL1-RUNX1 pathway in CRC cell lines. Results: The CRC tissues and cells exhibited elevated expression of APOL1. HCT116 and SW1116 cells' proliferation, migration, and invasion were suppressed by sh-APOL1, and sh-APOL1 also increased the expression of E-cadherin and decreased the expression of RUNX1, cyclin D1, ß-catenin, N-cadherin, and vimentin. APOL1 bound to the RUNX1 protein and regulated its protein levels. The counteractive effect of sh-APOL1 epithelial-mesenchymal transition (EMT), proliferation, migration, and invasion of CRC cells was counteracted by the overexpression of RUNX1. By silencing APOL1, the Wnt-ß-catenin pathway was able to restrain EMT and regulate the biological behavior processes in CRC cells. Conclusions: APOL1 has potential as a diagnostic biomarker for CRC. By preventing the Wnt-ß-catenin pathway from being activated, the sh-APOL1-binding protein RUNX1 inhibited the EMT and biological behavior of CRC cells.