Bussolati and colleagues demonstrated that breast cancer cells (MCF7, T-47D, MDA-MB231) express PAFR and produce PAF in response to in vitro stimulation with VEGF, bFGF, HGF, TNFα and thrombin 34, indicating that signals produced in the tumor microenvironment can induce activation of the PAFR pathway in tumor cells. The gene discussed is HGF; the disease is neoplasm.