Effects of Lentivirus-Mediated CIB1 Silencing on Biological Behavior of Breast Cancer Cells

Objective To investigate the effects of calcium and integrin-binding protein 1 (CIB1) on the cell proliferation, invasion, apoptosis, and migration of triple-negative breast cancer cells and its possible mechanism.

Methods MDA-MB-231 and MDA-MB-468 cells were divided into CIB1-knockdown(infected with CRISPR/Cas9 lentivirus) and negative-control groups. Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2′-deoxyuridine (EdU) assays were performed to detect cell proliferation. Cell apoptosis was determined through flow cytometry. Scratch and Transwell experiments were conducted to measure the migration and invasion abilities of cells. The mRNA and protein expression levels of β-catenin, adenomatous polyposis coli (APC), glycogen synthase kinase 3β (GSK-3β), and c-myc were detected via real-time quantitative polymerase chain reaction and Western blot.

Results Compared with the negative-control group, the CIB1-knockdown group showed decreased cell proliferation, invasion, and migration (P<0.05) and increased cell apoptosis (P<0.05). The mRNA and protein expressions of β-catenin, APC, and c-myc decreased (P<0.05), and that of GSK-3β increased (P<0.05).

Conclusion CIB1 knockdown can inhibit cell proliferation, invasion, and migration and promote the apoptosis of breast cancer cells. Its mechanism may be related to the inhibition of Wnt/β-catenin signaling pathway.