RCOR1 and neoplasm: As tumor cell plasticity and phenotype switching is associated with resistance to targeted therapies in melanoma and other cancers, and intermediate phenotypes are generally considered to be treatment sensitive (21, 22), we next investigated the effect of CoREST inhibition combined with the BRAFi PLX4032 (vemurafenib, referred to herein as PLX4032) on BRAFi-R melanoma cell proliferation.