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.
Silencing or inhibition of mutant FGFR3 in bladder cancer cell lines is associated with decreased malignant potential, confirming its important driver role in UC.
Recent precision medicine has shown that mutations in BC are frequently observed in FGFR3, RAS and PIK3CA genes, all of which correlate with RAS signaling networks.
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.
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.
We assessed the performance of associating a FGFR3 mutation assay and a DNA methylation analysis to improve bladder cancer detection and to predict disease recurrence of NMIBC patients.
Based on this, we classified high-risk non-muscle-invasive bladder tumors according to FGFR3 mutations and chromosomal changes into papillary and CIS-type tumors with high correlation to CIS status (p = 0.001).
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.
Recent developments in the field of molecular mutational pathway analyses based on next generation sequencing technology together with classic data derived from the description of mutations in the FGFR3 (fibroblast growth factor receptor 3) gene, mutations on TP53 gene, and cDNA technology profiling data gives support to a differentiated taxonomy of bladder cancer.
The two most important developments are the identification of a mutation in the fibroblast growth factor receptor 3 gene in more than 50% of urothelial carcinomas and the discovery of cDNA profiles characteristic of different subsets of bladder cancer.
We further demonstrate that activating mutations in FGFR3 associated with both multiple myeloma and bladder cancer can modulate expression of genes that regulate NFκB signaling, and promote both NFκB transcriptional activity and cell adhesion in a manner dependent on TAK1 expression in both cancer cell types.
The greater sensitivity of FGFR3 mutation detection over cytology in identifying the presence of low-grade, superficial bladder tumors represents a potential new tool to complement standard cytology in screening patients for bladder tumors and recurrent disease.