In order to better clarify their roles in tumor growth, the aim of the present study was to evaluate the lactate-mediated crosstalk of GPR81 and IGFBP6 through the determination of cell proliferation, wound healing, mitochondrial oxidative metabolism and oxidative stress levels in human breast cancer cells (MDA-MB-231) in vitro. The gene discussed is HCAR1; the disease is breast carcinoma.