Detection of multiple mutations in urinary exfoliated cells from male bladder cancer patients at diagnosis and during follow-up

Abstract

Most bladder cancer (BC) patients need life-long, invasive and expensive monitoring and treatment, making it a serious burden on the health system. Thus, there is a pressing need for an accurate test to assist diagnosis and surveillance of BC as an alternative to cystoscopy. Mutations in human TERT, FGFR3, PIK3CA, and RAS genes have been proposed as potential molecular markers in bladder tumor. Their concomitant presence in urine samples has not been fully explored.We investigated a panel of mutations in DNA from exfoliated urinary cells of 255 BC patients at diagnosis. Forty-one mutations in TERT, FGFR3, PIK3CA, and RAS were analyzed by SNaPshot assay in relation to clinical outcome. In 81 of these patients under surveillance, the same set of mutations was screened in additional 324 samples prospectively collected.The most common mutations detected in urine at diagnosis were in the TERT promoter. In non-invasive BC, these mutations were related to high risk and grade (p<0.0001) as well as progression to muscle-invasive disease (p=0.01), whereas FGFR3 mutations were observed in low-grade BC (p=0.02) and patients with recurrences (p=0.05). Stronger associations were observed for combined TERT and FGFR3 mutations and number of recurrences (OR: 4.54 95% CI: 1.23-16.79, p=0.02). Analyses of the area under the curve for combinations of mutations detected at diagnosis and follow-up showed an accuracy of prediction of recurrence of 0.80 (95% CI: 0.71-0.89).Mutations in urine of BC patients may represent reliable biomarkers. In particular, TERT and FGFR3 mutations have a good accuracy of recurrence prediction.

Uromonitor®as a novel sensitive and specific urine-based test for recurrence surveillance of patients with non-muscle invasive bladder cancer

“…Still, two cases were positive for FGFR3 mutations without evidence for recurrence after the follow-up terminus that dropped the specificity of Uromonitor ® to 96.3%. More than half of the cases presented at least one mutational event and it is reported that TERT promoter and FGFR3 mutations tend to occur more frequently together than per chance; the combination of both might constitute a more reliable biomarker for NMIBC recurrence monitoring [15,42]. In terms of the Uromonitor ® performance in comparison with other available options it presented improved features.…”

“…The combination of all these facts leads to the opportunity for developing new, alternative and minimally invasive methods to detect bladder cancer. As urine is in direct contact with the inner part of bladder, cells from the epithelium, including scammed cells from bladder tumors can exfoliate and be detected in urine and used to evaluate and monitor the presence of neoplasia in a non-invasive approach [14][15][16][17][18]. Over the years, many different non-invasive assays have been developed in order to search genetic and protein alterations well known to be involved in the development, progression and recurrence of bladder cancer, both in serum and urine samples with the purpose to diagnose and monitor bladder cancer [13,14,[19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35].…”

Implications of TERT promoter mutations and telomerase activity in urothelial carcinogenesis

“…Recurrent mutations in the death-associated protein (DAXX) and the alphathalassemia X-linked protein (ATRX) have been correlated with ALT occurrence and potentially contribute to ALT maintenance 33,34 . Of note, there is evidence that telomerase activity supresses ALT, although the suppressive mechanism is yet to be identified [34][35][36][37][38][39][40][41][42][43][44][45][46][47] . In a comprehensive analysis of 6,110 human tumour specimens from various cancer types, ALT was observed in only ~4% of samples 48 .…”

Bladder Cancer Markers and Recent Innovations

“…The presence of the FGFR3 mutation in urine is observed for low-grade tumors and seems to be associated with concomitant or future recurrence [57,58]. Methylation is also important: five targets were identified, including ventral and anterior homeobox 1 (WAX1) KCNV1, TAL1, PPOX1, and CFTR, which have a sensitivity of 88.68% and a specificity of 87.25%.…”