Fig. 1From: S6K1 amplification confers innate resistance to CDK4/6 inhibitors through activating c-Myc pathway in patients with estrogen receptor-positive breast cancerThe key genes related to the innate resistance of CDK4/6 inhibitors were explored by analysis of ctDNA derived from patients with breast cancer. A-D Schematic overview of the study design and analytical workflow. PFS: progression-free survival. ctDNA: circulating tumour DNA. ddPCR: droplet digital PCR. IHC: immunohistochemistry. Multi-IF: multiplex immunofluorescence. E The landscape of high-frequency altered genes in plasma from the discovery patient cohort. The plot shows patients with innate resistance or clinical benefit following palbociclib treatment, with individual information about numbers of metastases, treatment lines, and endocrine therapy drugs used in combination with palbociclib. S6K1 (i.e. RPS6KB1) amplification was observed in three patients with innate resistance to palbociclib but not in those with clinical benefitBack to article page