Nogués, LauraReglero, ClaraRivas, VerónicaSalcedo, AliciaLafarga, VanesaNeves, MariaRamos, PaulaMendiola, MartaBerjón, AlbertoStamatakis, KostasZhou, XiaoLu, Kun PingHardisson, DavidMayor, FedericoPenela, Petronila2017-03-282016Nogués, L., C. Reglero, V. Rivas, A. Salcedo, V. Lafarga, M. Neves, P. Ramos, et al. 2016. “G Protein-coupled Receptor Kinase 2 (GRK2) Promotes Breast Tumorigenesis Through a HDAC6-Pin1 Axis.” EBioMedicine 13 (1): 132-145. doi:10.1016/j.ebiom.2016.09.030. http://dx.doi.org/10.1016/j.ebiom.2016.09.030.http://nrs.harvard.edu/urn-3:HUL.InstRepos:31731797In addition to oncogenic drivers, signaling nodes can critically modulate cancer-related cellular networks to strength tumor hallmarks. We identify G-protein-coupled receptor kinase 2 (GRK2) as a relevant player in breast cancer. GRK2 is up-regulated in breast cancer cell lines, in spontaneous tumors in mice, and in a proportion of invasive ductal carcinoma patients. Increased GRK2 functionality promotes the phosphorylation and activation of the Histone Deacetylase 6 (HDAC6) leading to de-acetylation of the Prolyl Isomerase Pin1, a central modulator of tumor progression, thereby enhancing its stability and functional interaction with key mitotic regulators. Interestingly, a correlation between GRK2 expression and Pin1 levels and de-acetylation status is detected in breast cancer patients. Activation of the HDAC6-Pin1 axis underlies the positive effects of GRK2 on promoting growth factor signaling, cellular proliferation and anchorage-independent growth in both luminal and basal breast cancer cells. Enhanced GRK2 levels promote tumor growth in mice, whereas GRK2 down-modulation sensitizes cells to therapeutic drugs and abrogates tumor formation. Our data suggest that GRK2 acts as an important onco-modulator by strengthening the functionality of key players in breast tumorigenesis such as HDAC6 and Pin1.en-USBreast transformationCancerGRK2HDAC6Pin1AcetylationJournal Article2017-03-2810.1016/j.ebiom.2016.09.030