Protein tyrosine kinase 6 (PTK6) (PTK6)

Protein tyrosine kinase 6 (PTK6), also known as Breast tumor kinase (BRK), is a non-receptor tyrosine kinase that is frequently overexpressed in various cancers, most notably in over 60% of human breast cancers [1][2]. Unlike many other kinases, PTK6 expression is largely absent in normal mammary tissue, though it is found in the nuclei of normal skin and gastrointestinal epithelial cells where it promotes differentiation [3]. In malignant cells, PTK6 often translocates to the cytoplasm or plasma membrane, where it enhances signaling pathways related to cell proliferation, survival, and migration by interacting with targets such as STAT3, AKT, and EGFR [2][4]. Because of its role in promoting oncogenic phenotypes and its differential expression between normal and cancerous breast tissue, PTK6 is considered a promising therapeutic target [5]. Current drug discovery efforts focus on small-molecule inhibitors that target its ATP-binding site, with several experimental compounds showing efficacy in preclinical models, although no specific inhibitors have reached clinical approval yet [6]. Targeting PTK6 aims to disrupt these oncogenic signaling hubs and potentially sensitize tumor cells to existing chemotherapeutic or targeted agents [4][5].

Other names

Breast tumor kinaseBRKSikProtein-tyrosine kinase 6

ATP-competitive inhibition of the tyrosine kinase domain to block downstream signaling cascades including STAT3, AKT, and MAPK pathways [4][5].