High expression of kinesin KIF18B in estrogen receptor-positive breast cancer enhances cell proliferation and apoptosis resistance and predicts poor prognosis

Abstract

Objective To investigate the expression of kinesin KIF18B in breast cancer cells and its impact on the cell proliferation, apoptosis, and prognosis of estrogen receptor-positive(ER+) breast cancer. Methods The expression of KIF18B mRNA were detected using real-time fluorescent quantitative PCR in ER+ breast cancer cell lines and clinical specimens of ER+ breast cancer tissue. Two ER+ breast cancer cell lines (YCCB1 and T47D) were transfected with a small interfering RNA targeting KIF18B, and the changes in the proliferative activity and apoptosis of the cells following KIF18B silencing were investigated using a CCK-8 kit and flow cytometry, respectively. Kaplan-Meier analysis was performed to assess the value of KIF18B in evaluating the prognosis of patients with ER+ breast cancer. Results KIF18B was highly expressed in ER+ breast cancer cell lines and clinical specimens (P < 0.05). KIF18B silencing significantly suppressed the proliferation and enhanced apoptosis of the 2 ER+ breast cancer cell lines (P < 0.05). Analysis of Kaplan-Meier showed that ER+ breast cancer patients having a high expression of KIF18B mRNA had poorer overall survival and recurrence-free survival than those with a low KIF18B expression (P < 0.05); in the patients receiving tamoxifen therapy, a high expression level of KIF18B mRNA was associated with a poorer distant metastasis-free survival (DMFS) and recurrence-free survival (P < 0.05). Conclusion ER+ breast cancer expresses high level of kinesin KIF18B, which promotes the proliferation and enhances apoptosis resistance of the tumor cells. A high expression of kinesin KIF18B predicts a poor prognosis of patients with ER+ breast cancer.

Keywords

• kif18b
• breast cancer
• cell proliferation
• cell apoptosis