Resistance to Palbociclib involves multiple mechanisms amenable to targeting with drug holidays or drug switching to improve therapeutic outcome [Illumina]

Combination of CDK4/6 inhibitors and endocrine therapy has been shown to improve clinical outcome in advanced estrogen receptor-positive breast cancer. However, not all patients will benefit and relapse is inevitable making the identification of new therapeutic strategies/biomarkers of particular importance. MCF7, MCF7 LTED and T47D human breast cancer cell lines were treated long-term with palbociclib until they develop resistance and RNA extracted from the parental cell line and corresponding resistance cell line in order to interrogate gene changes.