To characterize the function of MORC2 and its PRD domain in breast cancer cells, cell proliferation and cell-cycle progression of MCF10A, MDA-MB-231, and Hs578T cells stably expressing pCDH, Flag-MORC2 WT, and Flag-MORC2 ΔPRD were evaluated using Cell Counting Kit-8 (CCK-8), colony formation assay, and flow cytometry, respectively. The gene discussed is MORC2; the disease is breast carcinoma.