Kinase targeting in basal-like breast cancer: CKS1B.

Breast cancer can be distinguished into two broad groups, luminal and basal, based on cytologic, morphologic, cytoskeletal and differentiation-based features.  While luminal breast cancers can be positive for expression of a hormone receptor (ESR/PGR/AR) or a growth factor receptor (ERBB2) and targeted accordingly clinically, basal-like breast cancers cannot.  Inadequate long-term control of disease (e.g., partial response [PR] or recurrence/relapse) reflects limited effectiveness of existing drugs that treat basal subtype disease.  Here we utilized whole transcriptome technologies (5, 6) to define the basal-like breast cancer kinome and phosphatome by measuring total transcription in the primary tumors of humans with basal-like as compared to luminal A and luminal B breast cancer to identify basal-like signaling features.  We describe one member of a group of kinases up-regulated and differentially expressed in human basal-like breast cancer, CKS1B, as a catalytically available enzyme and candidate therapeutic target for the adjunctive medical treatment of basal subtype breast cancer.