Background aims: CD24 is markedly overexpressed in ovarian cancer and plays a critical role in ovarian cancer survival and metastasis, rendering it an interesting target for anti-tumor therapy. Using short hairpin RNA (shRNA) targeting CD24, we aimed to investigate the anti-tumor efficacy of CD24 knockdown in ovarian cancer cells in vitro and in vivo.
Methods: CD24 shRNA vector (CD24-shRNA) and empty plasmid vector (EP) were transfected into ovarian cancer SKOV3 cells and the knockdown efficacy assessed by Western blot analysis. The effects of CD24 knockdown in SKOV3 cells in vitro, including cell viability and apoptosis, were determined using methyl thiazolyl blue tetrazolium bromide (MTT), flow cytometry and propidium iodide (PI) staining assays. The effects in vivo of CD24 knockdown on angiogenesis, cell proliferation and apoptosis were assessed using immunohistochemistry against CD31, proliferating cell nuclear antigen (PCNA) and terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) assays.
Results: Transfection of CD24-shRNA effectively down-regulated CD24 expression in vitro and in vivo. Administration of CD24-shRNA into nude mice bearing ovarian cancer significantly suppressed tumor volume growth.
Conclusions: Knockdown of CD24 expression by CD24-shRNA significantly inhibited cell viability and induced apoptosis of SKOV3 cells in vitro. Administration with CD24-shRNA in vivo suppressed tumor volume increase by microvessel density (MVD) decrease, cell proliferation inhibition and apoptosis induction. All the data suggested that knockdown of CD24 by shRNA might be a potential therapeutic approach against human ovarian cancer.