FYN is a member of the SRC family of kinases (SFKs), functionally distinct from other SFKs. It interacts with FAK and paxillin (PXN)- regulators of cell morphology and motility. We hypothesized that FYN is upregulated in prostate cancer (CaP).
Patients and Methods
Through datamining in Oncomine; cell line profiling with immunoblotting and quantitative RT-PCR; and immunohistochemical analysis, we describe FYN expression in CaP. This analysis included 32 cases of CaP, 9 prostatic intraepithelial neoplasia (PIN), and 19 normal. Samples were scored for the percentage of stained glands and intensity of staining (from 0-3). Each sample was assigned a composite score generated by multiplying percentage and intensity.
Datamining showed an 8-fold increase in FYN expression in CaP compared to normal tissue. This was specific to FYN and not present for other SFKs. Expression of FYN in CaP cell lines (LNCaP, 22Rv1, PC3, DuPro) was detected using quantitative RT-PCR and immunoblot. Expression of FYN and its signaling partners FAK and PXN was demonstrated in human tissue. Comparing normal to cancer, there was a 2.1-fold increase in median composite score for FYN (p<0.001) 1.7-fold increase in FAK (p<0.001), and a 2-fold increase in PXN (p<0.05). There was a 1.7-fold increase in FYN (p<0.05), a 1.6-fold increase in FAK (p<0.01) in CaP as compared to PIN.
These studies support the hypothesis that the FYN and its related signaling partners are upregulated in CaP and supports further investigation into the role of the FYN as a therapeutic target.