GeneChip expression profiling identified OLFML2A as a potential therapeutic target in TNBC cells

BACKGROUND: An elevated level of olfactomedin-like-2A (OLFML2A) is unfavorable for female breast cancer patients. Patients with a high mRNA level of OLFML2A receive a poor prognosis. Therefore, we speculate that inhibiting the expression of this gene may be beneficial to breast cancer patients. We previously found that silencing the OLFML2A gene by using mRNA interference significantly inhibited proliferation and migration in triple-negative breast cancer (TNBC) cells. METHODS: Cell activity and proliferation were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Celigo analyses. Cell migration and invasion were determined by wound-healing and transwell invasion assays. The mechanism of the inhibition of a small hairpin RNA that targets OLFML2A (shOLFML2A) was determined by using a GeneChip array, real-time quantitative PCR (RT-qPCR), and western blot analysis. RESULTS: Gene silencing by shOLFML2A induces apoptosis by promoting S phase arrest in TNBC cells. In addition, shOLFML2A decreased the progression of epithelial-mesenchymal transition (EMT). Additionally, microarray analysis showed that shOLFML2A significantly upregulated 428 genes and downregulated 712 genes. These significantly changed genes regulated DNA synthesis, chromosome alignment, microtubules and the cytoskeleton, cell movement, the cell cycle, cell necrosis, and apoptosis because they promoted G2/M DNA damage checkpoint regulation and p53 signaling, and because they inhibited integrin, hepatocyte growth factor (HGF), nerve growth Factor (NGF), and other tumor-promoting signaling pathways. CONCLUSIONS: shOLFML2A reduces cell proliferation, migration, and invasion and promotes cell apoptosis. Therefore, the results of the present study suggest that OLFML2A is a potential therapeutic target for TNBC.