Roberg-Larsen et al. also confirmed that compared to exosomes derived from an estrogen receptor (ER-) breast cancer cell line (MDA-MB-231), the levels of 27-OHC in exosomes from an ER+ breast cancer cell line (MCF-7) has increased, which provides complementary information with diagnostic value [108]. The gene discussed is ESR1; the disease is breast carcinoma.