1-tert-butyl-3-[6-(3,5-dimethoxy-phenyl)-2-(4-diethylamino-butylamino)-pyrido[2,3-d]pyrimidin-7-yl]-urea (PD173074), a selective tyrosine kinase inhibitor of fibroblast growth factor receptor-3 (FGFR3), inhibits cell proliferation of bladder cancer carrying the FGFR3 gene mutation along with up-regulation of p27/Kip1 and G1/G0 arrest.
Bladder cancer cell lines were exposed to normoxic or hypoxic conditions and examined for the expression of FGFR3 by quantitative PCR (qPCR) and western blotting, and miR-100 by qPCR.
A sensitive and quantitative assay using peptide nucleic acid-mediated real-time PCR was developed for detecting FGFR3 mutations in the urine samples and evaluated as a molecular marker for detecting intravesical recurrence of NMIBC in patients undergoing transurethral resection of bladder tumor.
Activating mutations of FGFR3 have been observed in up to 70% of non-muscle-invasive bladder tumors, while overexpression of a wild-type receptor, found in approximately 40% of tumors, has been correlated with more invasive disease.
Activating point mutations and protein overexpression of fibroblast growth factor receptors (FGFRs), especially FGFR3, are frequent events in bladder cancer.
Although activating mutations of fibroblast growth factor receptor 3 (FGFR3) are frequent in bladder tumors, little information is available on their specific effects in urothelial cells or the basis for the observed mutation spectrum.
An example of a TM domain pathogenic mutation is the Ala391-->Glu mutation in fibroblast growth factor receptor 3 (FGFR3), linked to Crouzon syndrome with acanthosis nigricans, as well as to bladder cancer.
Analysing only previously reported point mutations, TERT mutations were found in 55% of patients with bladder cancer (independent of stage), FGFR3 mutations in 30% of patients with bladder cancer, PIK3CA in 14% and TP53 mutations in 12% of patients with bladder cancer.