ESR1 and cancer: We detected increased levels of IL-6 and IL-8 proteins by ELISA in conditioned media of MCF-7, MDA-MB-231, and SK-BR-3 breast carcinoma cells transfected transiently with WT MMP-8, indicating that the response is likely a general one and not restricted to cancer cells that have a particular estrogen receptor status or amplified HER2.