FGFR3 expression in primary and metastatic urothelial carcinoma of the bladder

Erdafitinib or Chemotherapy in Advanced or Metastatic Urothelial Carcinoma

BACKGROUND

Erdafitinib is a pan-fibroblast growth factor receptor (FGFR) inhibitor approved for the treatment of locally advanced or metastatic urothelial carcinoma in adults with susceptible FGFR3/2 alterations who have progression after platinum-containing chemotherapy. The effects of erdafitinib in patients with FGFR-altered metastatic urothelial carcinoma who have progression during or after treatment with checkpoint inhibitors (anti-programmed cell death protein 1 [PD-1] or anti-programmed death ligand 1 [PD-L1] agents) are unclear.

METHODS

We conducted a global phase 3 trial of erdafitinib as compared with chemotherapy in patients with metastatic urothelial carcinoma with susceptible FGFR3/2 alterations who had progression after one or two previous treatments that included an anti-PD-1 or anti-PD-L1. Patients were randomly assigned in a 1:1 ratio to receive erdafitinib or the investigator's choice of chemotherapy (docetaxel or vinflunine). The primary end point was overall survival.

RESULTS

A total of 266 patients underwent randomization: 136 to the erdafitinib group and 130 to the chemotherapy group. The median follow-up was 15.9 months. The median overall survival was significantly longer with erdafitinib than with chemotherapy (12.1 months vs. 7.8 months; hazard ratio for death, 0.64; 95% confidence interval [CI], 0.47 to 0.88; P = 0.005). The median progression-free survival was also longer with erdafitinib than with chemotherapy (5.6 months vs. 2.7 months; hazard ratio for progression or death, 0.58; 95% CI, 0.44 to 0.78; P<0.001). The incidence of grade 3 or 4 treatment-related adverse events was similar in the two groups (45.9% in the erdafitinib group and 46.4% in the chemotherapy group). Treatment-related adverse events that led to death were less common with erdafitinib than with chemotherapy (in 0.7% vs. 5.4% of patients).

CONCLUSIONS

Erdafitinib therapy resulted in significantly longer overall survival than chemotherapy among patients with metastatic urothelial carcinoma and FGFR alterations after previous anti-PD-1 or anti-PD-L1 treatment. (Funded by Janssen Research and Development; THOR ClinicalTrials.gov number, NCT03390504.).

Identification of novel lncRNA prognostic biomarkers and their associated ceRNAs in bladder urothelial carcinoma

Bladder urothelial carcinoma (BUCA) is a common malignant tumor with a high rate of metastasis and recurrence. The lack of specific and sensitive biomarkers for the prognostic assessment makes it important to seek alternatives. Recent studies have demonstrated that long noncoding RNAs (lncRNAs) function as competitive endogenous RNAs (ceRNAs) and play an important role in BUCA prognosis. Therefore, this study aimed to establish a prognosis-related lncRNAs-microRNAs (miRNAs)-messenger RNA (mRNA) (pceRNA) network and identify novel prognostic biomarkers. Integrated weighted coexpression analysis, functional clustering, and ceRNA network were used for the prognostic assessment of BUCA. The transcriptome sequencing datasets of lncRNA, miRNA, and mRNA from The Cancer Genome Atlas database were used for the identification of key lncRNAs and construction of the lncRNAs expression signature for prognostic prediction of BUCA patients. Then, 14 differentially expressed lncRNAs (DE-lncRNAs) were identified as candidate prognostic RNAs based on the ceRNAs network and functional clustering. In the Cox regression analysis, two (AC008676.1 and ADAMTS9-AS1) of all DE-lncRNAs were significantly associated with overall survival (OS) of BUCA patients. This two DE-lncRNA signature was significantly correlated with OS and was an independent prognostic factor, which was confirmed in an independent dataset of GSE216037. Moreover, we constructed the pceRNA network that includes 2 DE-lncRNAs, 9 DE-miRNAs, and 10 DE-mRNAs. Pathway enrichment analysis showed that AC008676.1 and ADAMTS9-AS1 are involved in several cancer-related pathways such as proteoglycans in cancer and TGF-beta signaling pathway. The novel-identified DE-lncRNA prognostic signature and the pceRNA network in this study will be valuable risk predictors and diagnostic markers for BUCA.

FGFR3 mutation characterization identifies prognostic and immune-related gene signatures in bladder cancer

BACKGROUND

Immunotherapy and FGFR3-targeted therapy play an important role in the management of locally advanced and metastatic bladder cancer (BLCA). Previous studies indicated that FGFR3 mutation (mFGFR3) may be involved in the alterations of immune infiltration, which may affect the priority or combination of these two treatment regimes. However, the specific impact of mFGFR3 on the immunity and how FGFR3 regulates the immune response in BLCA to affect prognosis remain unclear. In this study, we aimed to elucidate the immune landscape associated with mFGFR3 status in BLCA, screen immune-related gene signatures with prognostic value, and construct and validate a prognostic model.

METHODS

ESTIMATE and TIMER were used to assess the immune infiltration within tumors in the TCGA BLCA cohort based on transcriptome data. Further, the mFGFR3 status and mRNA expression profiles were analyzed to identify immune-related genes that were differentially expressed between patients with BLCA with wild-type FGFR3 or mFGFR3 in the TCGA training cohort. An FGFR3-related immune prognostic score (FIPS) model was established in the TCGA training cohort. Furthermore, we validated the prognostic value of FIPS with microarray data in the GEO database and tissue microarray from our center. Multiple fluorescence immunohistochemical analysis was performed to confirm the relationship between FIPS and immune infiltration.

RESULTS

mFGFR3 resulted in differential immunity in BLCA. In total, 359 immune-related biological processes were enriched in the wild-type FGFR3 group, whereas none were enriched in the mFGFR3 group. FIPS could effectively distinguish high-risk patients with poor prognosis from low-risk patients. The high-risk group was characterized by a higher abundance of neutrophils; macrophages; and follicular helper, CD4, and CD8 T-cells than the low-risk group. In addition, the high-risk group exhibited higher expression of PD-L1, PD-1, CTLA-4, LAG-3, and TIM-3 than the low-risk group, indicating an immune-infiltrated but functionally suppressed immune microenvironment. Furthermore, patients in the high-risk group exhibited a lower mutation rate of FGFR3 than those in the low-risk group.

CONCLUSIONS

FIPS effectively predicted survival in BLCA. Patients with different FIPS exhibited diverse immune infiltration and mFGFR3 status. FIPS might be a promising tool for selecting targeted therapy and immunotherapy for patients with BLCA.

Large, Nested Variant of Urothelial Carcinoma Is Enriched with Activating Mutations in Fibroblast Growth Factor Receptor-3 among Other Targetable Mutations

The large, nested variant of urothelial carcinoma (LNVUC) is characterized by bland histomorphology mimicking that of benign von Brunn nests. In the current study, we aimed to investigate the Fibroblast Growth Factor Receptor-3 (FGFR-3) activation and missense mutation in 38 cases, including 6 cases diagnosed with LNVUC and 32 with metastatic invasive urothelial carcinoma (UC). Initially, six formalin-fixed paraffin-embedded (FFPE) tissue samples of the LNVUC were subjected to whole-exome sequencing (WES), and then we performed targeted sequencing on 32 cases of metastatic invasive UC of various morphological subtypes, which were interrogated for the FGFR3. Our results revealed 3/6 (50%) LNVUC cases evaluated by WES in our study showed an activating mutation in FGFR-3, 33% showed an activating mutation in PIK3CA, and 17% showed activating mutation in GNAS or MRE11. Additionally, 33% of cases showed a truncating mutation in CDKN1B. All LNVUC in our study that harbored the FGFR-3 mutation showed additional activating or truncating mutations in other genes. Overall, 6/32 (18.75%) cases of random metastatic invasive UC showed missense mutations of the FGFR-3 gene. The LNVUC variant showed the higher incidence of FGFR-3 mutations compared to other types of mutations. Additionally, all LNVUC cases show additional activating or truncating mutations in other genes, thus being amenable to novel targeted therapy.

FORT-1: Phase II/III Study of Rogaratinib Versus Chemotherapy in Patients With Locally Advanced or Metastatic Urothelial Carcinoma Selected Based on FGFR1/3 mRNA Expression

PURPOSE

Rogaratinib, an oral pan-fibroblast growth factor receptor (FGFR1-4) inhibitor, showed promising phase I efficacy and safety in patients with advanced urothelial carcinoma (UC) with FGFR1-3 mRNA overexpression. We assessed rogaratinib efficacy and safety versus chemotherapy in patients with FGFR mRNA-positive advanced/metastatic UC previously treated with platinum chemotherapy.

METHODS

FORT-1 (ClinicalTrials.gov identifier: NCT03410693) was a phase II/III, randomized, open-label trial. Patients with FGFR1/3 mRNA-positive locally advanced or metastatic UC with ≥ 1 prior platinum-containing regimen were randomly assigned (1:1) to rogaratinib (800 mg orally twice daily, 3-week cycles; n = 87) or chemotherapy (docetaxel 75 mg/m2, paclitaxel 175 mg/m2, or vinflunine 320 mg/m2 intravenously once every 3 weeks; n = 88). The primary end point was overall survival, with objective response rate (ORR) analysis planned following phase II accrual. Because of comparable efficacy between treatments, enrollment was stopped before progression to phase III; a full interim analysis of phase II was completed.

RESULTS

ORRs were 20.7% (rogaratinib, 18/87; 95% CI, 12.7 to 30.7) and 19.3% (chemotherapy, 17/88; 95% CI, 11.7 to 29.1). Median overall survival was 8.3 months (95% CI, 6.5 to not estimable) and 9.8 months (95% CI, 6.8 to not estimable; hazard ratio, 1.11; 95% CI, 0.71 to 1.72; P = .67). Grade 3/4 events occurred in 37 (43.0%)/4 (4.7%) patients and 32 (39.0%)/15 (18.3%), respectively. No rogaratinib-related deaths occurred. Exploratory analysis of patients with FGFR3 DNA alterations showed ORRs of 52.4% (11/21; 95% CI, 29.8 to 74.3) for rogaratinib and 26.7% (4/15; 95% CI, 7.8 to 55.1) for chemotherapy.

CONCLUSION

To our knowledge, these are the first data to compare FGFR-directed therapy with chemotherapy in patients with FGFR-altered UC, showing comparable efficacy and manageable safety. Exploratory testing suggested FGFR3 DNA alterations in association with FGFR1/3 mRNA overexpression may be better predictors of rogaratinib response.

Genetic Interference of FGFR3 Impedes Invasion of Upper Tract Urothelial Carcinoma Cells by Alleviating RAS/MAPK Signal Activity

Upper tract urothelial cancer (UTUC) is a less common disease in Western countries but has a high level of prevalence in Asian populations. Compared to bladder cancer, unique etiologic and genomic factors are involved in UTUC. Fibroblast growth factor receptor 3 (FGFR3) up-regulation has been proposed as a promising target for bladder cancer therapy. In this study, we aimed to profile the expression of FGFR3 in Asian and Caucasian UTUC tissues and to evaluate the in vitro therapeutic efficacy of small interference RNA (siRNA)-mediated FGFR3 silencing in UTUC treatment. The FGFR3 expression levels in renal pelvis tissues and microarray sections from Asian and Caucasian patients with UTUC, respectively, were measured via immunohistochemistry. The BFTC-909 and UM-UC-14 UTUC cell lines were used to examine the effects of FGFR3 silencing on proliferation, migration, epithelial-mesenchymal transition (EMT) marker expression, and signaling machinery. FGFR3 expression increased as the TNM stage increased in both Asian and Caucasian UTUC tumors, and no statistical difference was identified between the two groups. In vitro studies demonstrated that FGFR3 siRNA delivery significantly inhibited proliferation and migration and suppressed the expression of EMT markers and transcription factors in UTUC cells. Mechanistically, FGFR3 silencing alleviated the constitutive expression of RAS and the phosphorylation of MAPK signaling mediators, including ERK1/2 and JNK1/2. FGFR3 silencing elicited an apoptosis-inducing effect similar to that of FGFR inhibition. Conclusion: siRNA-targeted FGFR3 expression may impede the expansion and invasion of UTUC cells by alleviating the RAS/MAPK signaling pathway. The genetic interference of FGFR3 expression via siRNA in UTUC cells may constitute a useful therapeutic strategy.

Patient Selection Approaches in FGFR Inhibitor Trials-Many Paths to the Same End?

Inhibitors of fibroblast growth factor receptor (FGFR) signaling have been investigated in various human cancer diseases. Recently, the first compounds received FDA approval in biomarker-selected patient populations. Different approaches and technologies have been applied in clinical trials, ranging from protein (immunohistochemistry) to mRNA expression (e.g., RNA in situ hybridization) and to detection of various DNA alterations (e.g., copy number variations, mutations, gene fusions). We review, here, the advantages and limitations of the different technologies and discuss the importance of tissue and disease context in identifying the best predictive biomarker for FGFR targeting therapies.

Dual targeting of FGFR3 and ERBB3 enhances the efficacy of FGFR inhibitors in FGFR3 fusion-driven bladder cancer

BACKGROUND

Mutations and fusions in Fibroblast Growth Factor Receptor 3 (FGFR3) occur in 10-20% of metastatic urothelial carcinomas and confer sensitivity to FGFR inhibitors. However, responses to these agents are often short-lived due to the development of acquired resistance. The objective of this study was to identify mechanisms of resistance to FGFR inhibitors in two previously uncharacterised bladder cancer cell lines harbouring FGFR3 fusions and assess rational combination therapies to enhance sensitivity to these agents.

METHODS

Acquired resistance to FGFR inhibitors was generated in two FGFR3 fusion harbouring cell lines, SW780 (FGFR3-BAIAP2L1 fusion) and RT4 (FGFR3-TACC3 fusion), by long-term exposure to the FGFR inhibitor BGJ398. Changes in levels of receptor tyrosine kinases were assessed by phospho-RTK arrays and immunoblotting. Changes in cell viability and proliferation were assessed by the Cell-Titre Glo assay and by propidium iodide staining and FACS analysis.

RESULTS

Long term treatment of FGFR3-fusion harbouring SW780 and RT4 bladder cancer cell lines with the FGFR inhibitor BGJ398 resulted in the establishment of resistant clones. These clones were cross-resistant to the clinically approved FGFR inhibitor erdafitinib and the covalently binding irreversible FGFR inhibitor TAS-120, but remained sensitive to the MEK inhibitor trametinib, indicating resistance is mediated by alternate activation of MAPK signalling. The FGFR inhibitor-resistant SW780 and RT4 lines displayed increased expression of pERBB3, and strikingly, combination treatment with an FGFR inhibitor and the ATP-competitive pan-ERBB inhibitor AZD8931 overcame this resistance. Notably, rapid induction of pERBB3 and reactivation of pERK also occurred in parental FGFR3 fusion-driven lines within 24 h of FGFR inhibitor treatment, and combination treatment with an FGFR inhibitor and AZD8931 delayed the reactivation of pERBB3 and pERK and synergistically inhibited cell proliferation.

CONCLUSIONS

We demonstrate that increased expression of pERBB3 is a key mechanism of adaptive resistance to FGFR inhibitors in FGFR3-fusion driven bladder cancers, and that this also occurs rapidly following FGFR inhibitor treatment. Our findings demonstrate that resistance can be overcome by combination treatment with a pan-ERBB inhibitor and suggest that upfront combination treatment with FGFR and pan-ERBB inhibitors warrants further investigation for FGFR3-fusion harbouring bladder cancers.

New Directions and Challenges in Targeted Therapies of Advanced Bladder Cancer: The Role of FGFR Inhibitors

Simple Summary

The aim of this study was to present and analyze the up-to-date literature describing the epidemiology, genetics, and histopathology of bladder cancer, as well as the latest methods of bladder cancer treatment. The treatment of urothelial cancer was divided depending on its stage and advancement. FGFR3 mutations and overexpression occur more frequently in bladder cancer than any other malignancy, occurring in nearly 80% of the tumors. Closer acknowledgement of targeted therapy will help physicians to navigate specific groups of patients for whom this treatment strategy can be beneficial. To that end, intense clinical research was conducted, bringing evidence for effectiveness and safety of FGFR inhibitors. Recent years of research have truly set a positive perspective for the better understanding of the complex issue of urothelial carcinoma pathology and management.

Abstract

Bladder neoplasms, including the most common urothelial carcinoma, have been an escalating problem for years, especially in highly developed countries. Recent decades have brought us a steadily growing share of this cancer in terms of both morbidity and mortality statistics. Bladder neoplasms are not only a therapeutic challenge but also an economical one due to the demanding, costly diagnostics and treatment. The treatment of urothelial cancer can be divided depending on the stage and advancement; thus, we can distinguish three main categories: non-muscle invasive bladder cancer, conventionally treated by surgical interventions; muscle invasive bladder cancer, conventionally treated with chemotherapeutics; and advanced bladder cancer with distant metastases, conventionally treated with the intensive chemotherapy in the MVAC scheme (methotrexate, vinblastine, doxorubicin, and cisplatin). Recent years have brought a breakthrough: immunotherapy and targeted therapy were discovered to be beneficial for patients disqualified from chemotherapy or patients who progressed despite treatment. This literature review summarizes the latest research into the use of targeted therapy in the treatment of advanced bladder cancer, its benefits, and its limitations.

A phase 1 study of LY3076226, a fibroblast growth factor receptor 3 (FGFR3) antibody-drug conjugate, in patients with advanced or metastatic cancer

Background We report a Phase 1 study of LY3076226, an antibody-drug conjugate composed of human IgG1 monoclonal antibody against the human FGFR3 attached with a cleavable linker to the maytansine derivative DM4 in patients with advanced or metastatic cancer. Methods This study was comprised of two parts: (A) dose escalation in patients with advanced or metastatic cancer and (B) dose expansion in patients with urothelial carcinoma with locally determined FGFR3 alterations. The dose range of LY3076226 tested was 0.2-5.0 mg/kg as an intravenous infusion on Day 1 of each 21-day cycle. The primary objective was to determine a recommended phase 2 dose (RP2D). Results Twenty-five patients were enrolled (Part A: 22, Part B: 3) and received ≥ 1 dose of LY3076226. No dose-limiting toxicities were reported. LY3076226 was generally well tolerated; most of the toxicities were Grade 1 or 2. Two patients experienced treatment-related Grade 3 toxicity (embolism and decreased platelet count). Four patients experienced serious adverse events (not treatment-related), all in Part A. Dose-proportional exposure was observed, with an estimated half-life of 2-7 days. No responses were seen with LY3076226 treatment. Stable disease persisting for > 6 months was observed in 1 patient receiving 3.2 mg/kg of LY3076226. Conclusion The study demonstrates acceptable safety and tolerability of LY3076226 up to the 5.0 mg/kg dose. Recruitment was stopped due to pipeline prioritization. Dose escalation of LY3076226 beyond 5.0 mg/kg in patients with advanced tumors may be possible. The trial was registered on August 19, 2015 under identifier NCT02529553 with ClinicalTrials.gov.

Differences in genomic profile of high-grade urothelial carcinoma according to tumor location

OBJECTIVES

To establish targeted therapies based on the molecular landscape in upper urinary tract urothelial carcinoma (UTUC), we tried to investigate the molecular characteristics of UTUC compared with those of bladder urothelial carcinoma (BLUC) by next-generation sequencing (NGS).

MATERIALS AND METHODS

We selected 71 high-grade infiltrating urothelial carcinoma tissue specimens from 33 UTUC and 38 BLUC patients. NGS analysis was performed with the Illumina TruShigt Oncology-500 panel.

RESULTS

Both UTUC and BLUC showed similar clinicopathologic characteristics, as well as morphologic similarities. The median tumor mutation burden (TMB) of all cases was 7.8 mutations/Mb. The majority of alterations were missense mutations. TP53 (40/71, 56.3%), KDM6A (30/71, 42.3%), and TERT promoter mutations (23/71, 32.4%) were observed regardless of tumor location. Compared with UTUC, BLUC showed frequent mutations in several genes: ARID1A (P = 0.001), ASXL1 (P = 0.017), ERBB3 (P = 0.005), PRKDC (P = 0.004) and RB1 (P = 0.041). On the contrary, copy number loss of FGFR3 was observed more in UTUC than BLUC (P = 0.018). Also, 6 cases showed oncogenic fusions: 3 cases with FGFR2 fusion in UTUC and 3 cases with FGFR3-TACC3 fusion in BLUC.

CONCLUSION

Despite the small cohort size, we identified genetic differences between UTUC and BLUC in Korean patients by NGS. An understanding of the comprehensive molecular characteristics of UTUC and BLUC may be helpful in detecting candidates for targeted therapy.

A hypoxia related long non-coding RNA signature could accurately predict survival outcomes in patients with bladder cancer

Hypoxia plays a significant role in tumor progression. This study aimed to develop a hypoxia-related long noncoding RNA (lncRNA) signature for predicting survival outcomes of patients with bladder cancer (BC). The transcriptome and clinicopathologic data were downloaded from The Cancer Genome Atlas (TCGA) database. Univariate Cox regression analysis and Lasso regression analysis were used to screened lncRNAs. Ten lncRNAs were screened out and included into the hypoxia lncRNA signature. The risk score based on hypoxia lncRNA signature could accurately predict the survival outcomes of BC patients. Immune infiltration analysis showed that six types of immune cells had significant different infiltration. Tumor mutation burden (TMB) analysis showed that the risk scores between the wild types and the mutation types of TP53, FGFR3, and RB1 were significantly different. Gene Set Enrichment Analysis (GSEA) showed that cancer-associated pathways belonged to the high risk groups and immune-related signal pathways were enriched into the low risk group. Then, we constructed a predictive model with the risk score, age, and clinical stage, which showed a robust prognostic performance. An lncRNA-mRNA coexpression network was constructed, which contained 62 lncRNA-mRNA links among 10 lncRNAs and 40 related mRNAs. In summary, the hypoxia lncRNA signature could accurately predict prognosis, chemotherapy and immunotherapy response in patients with BC and was relevant to clinicopathologic parameters and immune cell infiltration.

Prognostic Role of FGFR Alterations and FGFR mRNA Expression in Metastatic Urothelial Cancer Undergoing Checkpoint Inhibitor Therapy

OBJECTIVE

To examine the disease-specific survival(DSS) after checkpoint inhibitor(CPI) therapy based on FGFR alterations and FGFR mRNA expression levels in patients with metastatic urothelial cancer(mUCa) within a multi-center cohort.

METHODS

Within a cohort of 72 patients with mUCa from five academic centers in Germany FGFR alterations, as well as FGFR1-4 mRNA expression levels in tumor samples from the primary tumor or metastatic sites. Spearman rank correlations, logistic regression, as well as Kaplan-Meier survival analyses and univariate Cox proportional hazards regression models were employed to examine the impact of different FGFR patterns on the DSS after CPI treatment.

RESULTS

FGFR3 mutations or gene fusions (gene alterations) were detected in 16.9% of all samples. Patients with or without FGFR3 gene alterations did not show different oncological outcomes undergoing CPI treatment. Low expression of FGFR2 mRNA alone, as well as the combination of either low FGFR2mRNA expression and FGFR3 gene alteration or high FGFR3mRNA expression (P = 0.027), identified a subgroup of patients with unfavorable outcomes, comprising 40% of the total cohort. This trend was also observed in univariate Cox proportional hazards regression analysis(FGFR3 gene alteration: Hazard ratio(HR) 5.33, 95%Confidence interval(CI)1.76-15.0, P = 0.004; FGFR3mRNA expression:HR 3.04, 95%CI 1.40-7.13, P = 0.005).

CONCLUSION

Assessment of FGFR mRNA expression identified a high-risk subgroup of patients with mUCa. These patients showing overexpression of FGFR3 mRNA were found to have unfavorable DSS after CPI treatment. Using this approach may be suitable for identifying a patient population with poor response to CPI treatment, which may benefit from early FGFR inhibition.

Development and Validation of a Hypoxia-Related Signature for Predicting Survival Outcomes in Patients With Bladder Cancer

Objectives

This study aimed to develop and validate a hypoxia signature for predicting survival outcomes in patients with bladder cancer.

Methods

We downloaded the RNA sequence and the clinicopathologic data of the patients with bladder cancer from The Cancer Genome Atlas (TCGA) (https://portal.gdc.cancer.gov/repository?facetTab=files) and the Gene Expression Omnibus (GEO) (https://www.ncbi.nlm.nih.gov/geo/) databases. Hypoxia genes were retrieved from the Molecular Signatures Database (https://www.gsea-msigdb.org/gsea/msigdb/index.jsp). Differentially expressed hypoxia-related genes were screened by univariate Cox regression analysis and Lasso regression analysis. Then, the selected genes constituted the hypoxia signature and were included in multivariate Cox regression to generate the risk scores. After that, we evaluate the predictive performance of this signature by multiple receiver operating characteristic (ROC) curves. The CIBERSORT tool was applied to investigate the relationship between the hypoxia signature and the immune cell infiltration, and the maftool was used to summarize and analyze the mutational data. Gene-set enrichment analysis (GSEA) was used to investigate the related signaling pathways of differentially expressed genes in both risk groups. Furthermore, we developed a model and presented it with a nomogram to predict survival outcomes in patients with bladder cancer.

Results

Eight genes (AKAP12, ALDOB, CASP6, DTNA, HS3ST1, JUN, KDELR3, and STC1) were included in the hypoxia signature. The patients with higher risk scores showed worse overall survival time than the ones with lower risk scores in the training set (TCGA) and two external validation sets (GSE13507 and GSE32548). Immune infiltration analysis showed that two types of immune cells (M0 and M1 macrophages) had a significant infiltration in the high-risk group. Tumor mutation burden (TMB) analysis showed that the risk scores between the wild types and the mutation types of TP53, MUC16, RB1, and FGFR3 were significantly different. Gene-Set Enrichment Analysis (GSEA) showed that immune or cancer-associated pathways belonged to the high-risk groups and metabolism-related signal pathways were enriched into the low-risk group. Finally, we constructed a predictive model with risk score, age, and stage and validated its performance in GEO datasets.

Conclusion

We successfully constructed and validated a novel hypoxia signature in bladder cancer, which could accurately predict patients’ prognosis.

Fibroblast Growth Factor Receptors (FGFRs) and Noncanonical Partners in Cancer Signaling

Increasing evidence indicates that success of targeted therapies in the treatment of cancer is context-dependent and is influenced by a complex crosstalk between signaling pathways and between cell types in the tumor. The Fibroblast Growth Factor (FGF)/FGF receptor (FGFR) signaling axis highlights the importance of such context-dependent signaling in cancer. Aberrant FGFR signaling has been characterized in almost all cancer types, most commonly non-small cell lung cancer (NSCLC), breast cancer, glioblastoma, prostate cancer and gastrointestinal cancer. This occurs primarily through amplification and over-expression of FGFR1 and FGFR2 resulting in ligand-independent activation. Mutations and translocations of FGFR1-4 are also identified in cancer. Canonical FGF-FGFR signaling is tightly regulated by ligand-receptor combinations as well as direct interactions with the FGFR coreceptors heparan sulfate proteoglycans (HSPGs) and Klotho. Noncanonical FGFR signaling partners have been implicated in differential regulation of FGFR signaling. FGFR directly interacts with cell adhesion molecules (CAMs) and extracellular matrix (ECM) proteins, contributing to invasive and migratory properties of cancer cells, whereas interactions with other receptor tyrosine kinases (RTKs) regulate angiogenic, resistance to therapy, and metastatic potential of cancer cells. The diversity in FGFR signaling partners supports a role for FGFR signaling in cancer, independent of genetic aberration.

Spotlight on PSMA as a new theranostic biomarker for bladder cancer

Bladder cancer (BCa) patients are diagnosed by cytology and cystoscopy. However, these diagnostic tests bear some limitations. We sought for reliable biomarkers to better determine BCa extension. Prostate-specific membrane antigen (PSMA) appears to fulfill this requirement in prostate cancer but its role in BCa has not been established yet. We then analyzed 87 bladder tissue samples from 74 patients assessing PSMA expression by immunohistochemistry. The median PSMA expression, exclusively found in tumor neovasculature, in terms of H-score significantly differed between non-tumor samples and tumor samples (p = 0.00288) showing a higher neovasculature-related PSMA expression. No differences were observed in relation to tumor type, grade and stage. BCa neovasculature-related PSMA overexpression may be useful in defining the degree of extension of the neoplasm. In addition, testing PSMA expression by immunohistochemistry may hold theranostic implications both considering anti-angiogenesis agents and radio-labelled PSMA ligands for intracavitary radionuclide therapy. In our opinion, BCa neovasculature-related PSMA overexpression may be considered an apt target for anti-angiogenesis and radionuclide treatment in BCa, once the evaluation of tumor-retention time for the appropriateness of long half-life therapeutic PSMA ligands as radionuclide treatment will be performed.

Emerging agents for the treatment of metastatic urothelial cancer

Over the past few decades, platinum-based combination chemotherapy (PBCC) has been the preferred initial therapy for metastatic urothelial cancer (mUC). However, despite a response rate of approximately 50%, a small proportion of patients with distant metastases may be cured by cisplatin-based combination chemotherapy (CBCC). In addition, up to 50% of patients are not eligible for CBCC due to age or comorbidities. Furthermore, adverse effects from PBCC are a major concern. The emergence of check-point inhibitors (CPIs), particularly those with antibodies directed against programmed cell death 1 protein (PD-1) or its ligand (PD-L1), advanced the treatment of mUC. Avelumab switch-maintenance therapy is recommended in patients with locally advanced or mUC who did not progress on initial PBCC. With the recent advances in tumor molecular biology and the discovery of actionable therapeutic targets, the clinical application of targeted therapy is now being explored for mUC. Erdafitinib, a tyrosine kinase inhibitor of FGFR1-4, has shown positive outcomes in patients with advanced UC with FGFR alterations. Another recent technological development is antibody-drug conjugates (ADCs), which are complex molecules composed of an antibody linked to a biologically active cytotoxic drug (payload) that targets and kills tumor cells while sparing healthy cells. Enfortumab vedotin, a monoclonal antibody targeting nectin-4 conjugated to monomethyl auristatin E, has demonstrated clinically significant efficacy in patients who do not respond to both cytotoxic chemotherapy and CPIs. In this review, we describe switch-maintenance therapies using CPI, various targeted agents, and ADCs that have been investigated for mUC treatment.

Synthesis and structure-activity relationships of pyrimidine derivatives as potent and orally active FGFR3 inhibitors with both increased systemic exposure and enhanced in vitro potency

Fibroblast growth factor receptor 3 (FGFR3) is an attractive therapeutic target for the treatment of patients with bladder cancer harboring genetic alterations in FGFR3. We identified pyrimidine derivative 20b, which induced tumor regression following oral administration to a bladder cancer xenograft mouse model. Compound 20b was discovered by optimizing lead compound 1, which we reported previously. Specifically, reducing the molecular size of the substituent at the 4-position and replacing the linker of the 5-position in the pyrimidine scaffold resulted in an increase in systemic exposure. Furthermore, introduction of two fluorine atoms into the 3,5-dimethoxyphenyl ring enhanced FGFR3 inhibitory activity. Molecular dynamics (MD) simulation of 20b suggested that the fluorine atom interacts with the main chain NH moiety of Asp635 via a hydrogen bond.

Fibroblast growth factor receptor: A systematic review and meta-analysis of prognostic value and therapeutic options in patients with urothelial bladder carcinoma

To evaluate the oncologic prognostic value of fibroblast growth factor receptor (FGFR) and to assess the safety and efficacy of its inhibitors in patients with urothelial bladder carcinoma. A literature search using PubMed, Scopus, and Cochrane Library was conducted on June 2020 to identify relevant studies according to the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. The pooled recurrence-free survival (RFS), progression-free survival (PFS), and cancer-specific survival (CSS) were calculated using a fixed or random effects model in patients with nonmuscle invasive bladder cancer (NMIBC). Overall, 62 studies comprising 9,229 patients were eligible and included in this systematic review and meta-analysis. Both FGFR3 mutation and protein overexpression were significantly associated with RFS, PFS, CSS, and overall survival. FGFR3 mutation was associated with worse RFS and better PFS (pooled hazard ratio: 1.30; 95% confidence interval: 1.08-1.57, and pooled hazard ratio: 0.62; 95% confidence interval: 0.42-0.92, respectively) in patients with NMIBC. In 11 studies reporting on the response to FGFR inhibitors, complete response rates, disease control rates, and overall response rate of 0% to 8%, 59.3% to 64.2%, and 40% were reported for dovitinib, infigratinib, and erdafitinib, respectively. Based on this study, FGFR3 mutation is a statistically significant prognostic factor for RFS in NMIBC. FGFR inhibitors have measurable benefit in patients with advanced and metastatic urothelial carcinoma. However, the results of ongoing RCTs and future well-designed studies are awaited to capture the differential biologic and clinical behavior of tumors harboring FGFR while helping to identify those who are most likely to benefit from FGFR inhibitors.

FGFR3 – a Central Player in Bladder Cancer Pathogenesis?

The identification of mutations in FGFR3 in bladder tumors in 1999 led to major interest in this receptor and during the subsequent 20 years much has been learnt about the mutational profiles found in bladder cancer, the phenotypes associated with these and the potential of this mutated protein as a target for therapy. Based on mutational and expression data, it is estimated that >80% of non-muscle-invasive bladder cancers (NMIBC) and ∼40% of muscle-invasive bladder cancers (MIBC) have upregulated FGFR3 signalling, and these frequencies are likely to be even higher if alternative splicing of the receptor, expression of ligands and changes in regulatory mechanisms are taken into account. Major efforts by the pharmaceutical industry have led to development of a range of agents targeting FGFR3 and other FGF receptors. Several of these have entered clinical trials, and some have presented very encouraging early results in advanced bladder cancer. Recent reviews have summarised the drugs and related clinical trials in this area. This review will summarise what is known about the effects of FGFR3 and its mutant forms in normal urothelium and bladder tumors, will suggest when and how this protein contributes to urothelial cancer pathogenesis and will highlight areas that may benefit from further study.

Genome-wide transcriptional analysis of Aristolochia manshuriensis induced gastric carcinoma

Context: Aristolochia manshuriensis Kom (Aristolochiaceae) (AMK) is known for toxicity and mutagenicity.Objective: The tumorigenic role of AMK has yet to be understood.Materials and methods: AMK extracts were extracted from root crude drug. SD (Sprague Dawley) rats underwent gavage with AMK (0.92 g/kg) every other day for 10 (AMK-10) or 20 (AMK-20) weeks. Stomach samples were gathered for histopathological evaluation, microarray and mRNA analysis.Results: The gastric weight to body weight ratio (GW/BW) is 1.7 in the AMK-10 cohort, and 1.8 in AMK-20 cohort compared to control (CTL) cohort. Liver function was damaged in AMK-10 and AMK-20 rats compared to CTL rats. There were no significant changes of CRE (creatinine) in AMK-10 and AMK-20 rats. Histopathological analysis revealed that rats developed dysplasia in the forestomach in AMK-10 rats, and became gastric carcinoma in AMK-20 rats. Genes including Mapk13, Nme1, Gsta4, Gstm1, Jun, Mgst2, Ggt6, Gpx2, Gpx8, Calml3, Rasgrp2, Cd44, Gsr, Dgkb, Rras, and Amt were found to be critical in AMK-10 and AMK-20 rats. Pik3cb, Plcb3, Tp53, Hras, Myc, Src, Akt1, Gnai3, and Fgfr3 worked in AMK-10 rats, and PDE2a and PDE3a played a pivotal role in AMK-20 rats.Discussion and conclusions: AMK induced benign or malignant gastric tumours depends on the period of AMK administration. Genes including Mapk13, Nme1, Gsta4, Gstm1, Jun, Mgst2, Ggt6, Gpx2, Gpx8, Calml3, Rasgrp2, Cd44, Gsr, Dgkb, Rras, Amt, Pik3cb, Plcb3, Tp53, Hras, Myc, Src, Akt1, Gnai3, Fgfr3, PDE2a, and PDE3a were found to be critical in aristolochic acid-induced gastric tumour process.

Analysis of FGFR3 and HRAS genes in patients with bladder cancer

Background: Bladder cancer is the most frequent malignancy that affects the urinary tract. Studies have shown different types of FGFR3 and HRAS genes mutations in human bladder cancer, with a comprehensive range of mutation number in various populations. This study aimed to determine the specific point mutations of these 2 genes among Iranian patients with bladder cancer. Methods: In this study, 100 specimens of patients with transitional cell carcinoma were analyzed. All samples were examined for FGFR3 and HRAS mutations using PCR and direct DNA sequencing methods. Results: A total of 9 pathogenic mutations and 9 polymorphisms were found in 2 exons (7 and 15) of the FGFR3 genes in patients with bladder cancer (S249Y, I633I, L645L, D646E, Y647*, D628V, P250T, Q263H, Y305H). However, no mutation was found in exon 10 of FGFR3 and exon 1 of HRAS genes. Conclusion: In this study, 5 mutations were found in FGFR3 gene that have not been detected previously. There was no mutation in exon 10 of FGFR3 and exon1 of HRAS. The results of this study confirmed the association of ethnic-genetic factors in the occurrence of bladder cancer, so that these variables may not be present in all ethnic groups.

Systemic treatment for advanced urothelial cancer: an update on recent clinical trials and current treatment options

After cisplatin-based chemotherapy became the standard treatment for metastatic urothelial cancer (mUC), very little progress has been made in the treatment landscape of this condition until recently. With increased knowledge about the molecular biology of mUC and advances in the field of cancer immunobiology, there has been an explosion in the number of clinical trials for mUC, and systemic treatment of mUC is rapidly changing. Despite the availability of several novel therapeutic agents, cisplatin-based cytotoxic chemotherapy remains the standard, first-line treatment option. Immune checkpoint inhibitors (ICIs), including programmed death-1 and programmed death ligand-1 inhibitors, are preferred second-line treatment options that are also used in first-line cisplatin-ineligible settings. For patients with actionable fibroblast growth factor receptor 2 (FGFR2) or FGFR3 genomic alterations, erdafitinib can be considered after platinum-based treatment. Enfortumab vedotin, a monoclonal antibody targeting nectin-4 conjugated to monomethyl auristatin E, has been approved for patients who do not respond to both cytotoxic chemotherapy and ICIs. In this review, we address the clinical trial data that have established the current standard treatments and ongoing clinical trials of various agents with different mechanisms as well as provide a brief overview of current practice guidelines and recommendations in patients with mUC.

Update on Circulating Tumor Cells in Genitourinary Tumors with Focus on Prostate Cancer

Current developments in the treatment of genitourinary tumors underline the unmet clinical need for biomarkers to improve decision-making in a challenging clinical setting. The detection of circulating tumor cells (CTCs) has become one of the most exciting and important new approaches to identifying biomarkers at different stages of disease in a non-invasive way. Potential applications of CTCs include monitoring treatment efficacy and early detection of progression, selecting tailored therapies, as well as saving treatment costs. However, despite the promising implementation of CTCs in a clinical scenario, the isolation and characterization of these cells for molecular studies remain expensive with contemporary platforms, and significant technical challenges still need to be overcome. This updated, critical review focuses on the state of CTCs in patients with genitourinary tumor with focus on prostate cancer, discussing technical issues, main clinical results and hypothesizing potential future perspectives in clinical scenarios.

MKP-1 overexpression is associated with chemoresistance in bladder cancer via the MAPK pathway

Mitogen activated protein kinase phosphatase-1 (MKP-1) has been revealed to be overexpressed in bladder cancer, particularly in non-muscle invasive bladder cancer. MKP-1 may also be associated with chemotherapy resistance. However, the underlying mechanism is yet to be elucidated. The current study investigated the expression of MKP-1 by performing immunohistochemistry in surgically resected specimens obtained from primary and recurrent patients with bladder cancer. The results revealed that MKP-1 expression increased in recurrent patients. Additionally, a 3D model of the human bladder cancer cell line, RT112, was established to determine the role of MKP-1 in drug resistance. The results demonstrated that MKP-1 overexpression protected bladder cancer cells against cell death. Contrarily, MKP-1 knockdown was revealed to sensitize cells to death. In addition, the application of MAPK inhibitors effectively increased RT112 cell sensitivity to pirarubicin. In conclusion, the results of the current study indicated that MKP-1 treatment resulted in bladder cancer cell chemoresistance via JNK, ERK and p38 pathways. MKP-1 may also serve as a potential therapeutic target for chemoresistance in patients with bladder cancer.

The future of bladder cancer therapy: Optimizing the inhibition of the fibroblast growth factor receptor

Therapeutic options for metastatic bladder cancer (BC) have seen minimal evolution over the past 30 years, with platinum-based chemotherapy remaining the mainstay of standard of care for metastatic BC. Recently, five immune checkpoint inhibitors (ICIs) have been approved by the FDA as second-line therapy, and two ICIs are approved as first-line treatment in selected patients. Molecular alterations of muscle-invasive bladder cancer (MIBC) have been reported by The Cancer Genome Atlas. About 15% of patients with MIBC have molecular alterations in the fibroblast growth factor (FGF) axis. Several ongoing trials are testing novel FGF receptor (FGFR) inhibitors in patients with FGFR genomic aberrations. Recently, erdafitinib, a pan-FGFR inhibitor, was approved by the FDA in patients with metastatic BC who have progressed on platinum-based chemotherapy. We reviewed the literature over the last decade and provide a summary of current knowledge of FGF signaling, and the prognosis associated with FGFR mutations in BC. We cover the role of FGFR inhibition with non-selective and selective tyrosine kinase inhibitors as well as novel agents in metastatic BC. Efficacy and safety data including insights from mechanism-based toxicity are reported for selected populations of metastatic BC with FGFR aberrations. Current strategies to managing resistance to anti-FGFR agents is addressed, and the importance of developing reliable biomarkers as the therapeutic landscape moves towards an individualized therapeutic approach.

A genetically defined disease model reveals that urothelial cells can initiate divergent bladder cancer phenotypes

Small cell carcinoma of the bladder (SCCB) is a lethal variant of bladder cancer with no effective treatment. A lack of available preclinical models and clinical cohorts impedes our understanding of its molecular pathogenesis. In this study, we provided a tumor model as functional evidence showing that SCCB and other bladder cancer phenotypes can be derived from normal human urothelial cells. We further demonstrated that SCCB has a distinct transcriptome and identified SCCB-associated cell surface proteins (CSPs) that can be further evaluated as potential therapeutic targets. We show that our model shares CSP profile with clinical SCCB samples. Our findings create a foundation to understand the molecular underpinnings of SCCB and provide tools for developing therapeutic strategies.

Small cell carcinoma of the bladder (SCCB) is a rare and lethal phenotype of bladder cancer. The pathogenesis and molecular features are unknown. Here, we established a genetically engineered SCCB model and a cohort of patient SCCB and urothelial carcinoma samples to characterize molecular similarities and differences between bladder cancer phenotypes. We demonstrate that SCCB shares a urothelial origin with other bladder cancer phenotypes by showing that urothelial cells driven by a set of defined oncogenic factors give rise to a mixture of tumor phenotypes, including small cell carcinoma, urothelial carcinoma, and squamous cell carcinoma. Tumor-derived single-cell clones also give rise to both SCCB and urothelial carcinoma in xenografts. Despite this shared urothelial origin, clinical SCCB samples have a distinct transcriptional profile and a unique transcriptional regulatory network. Using the transcriptional profile from our cohort, we identified cell surface proteins (CSPs) associated with the SCCB phenotype. We found that the majority of SCCB samples have PD-L1 expression in both tumor cells and tumor-infiltrating lymphocytes, suggesting that immune checkpoint inhibitors could be a treatment option for SCCB. We further demonstrate that our genetically engineered tumor model is a representative tool for investigating CSPs in SCCB by showing that it shares a similar a CSP profile with clinical samples and expresses SCCB–up-regulated CSPs at both the mRNA and protein levels. Our findings reveal distinct molecular features of SCCB and provide a transcriptional dataset and a preclinical model for further investigating SCCB biology.

Erdafitinib for the treatment of metastatic bladder cancer

Introduction: Since the approval of immune checkpoint inhibitors (ICIs), there has been continuing and significant progress in urothelial cancer (UC) treatment. However, only about one fifth of UC patients respond to ICI. Recently, erdafitinib was developed for treating locally advanced or metastatic UC (mUC) with FGFR3 or FGFR2 alterations, accounting for 15-20% of patients. Erdafitinib is the first targeted therapy ever approved for mUC.Areas covered: This review summarizes the preclinical and clinical data on erdafitinib for UC. PubMed search and relevant articles presented at international conferences were used for the literature search.Expert opinion: The FDA approval of erdafitinib provided a new treatment option for FGFR-altered UC progressing on platinum-based chemotherapy. It is not clear whether FGFR inhibitor is a preferred second-line treatment choice to ICI. Compared to ICI, erdafitinib has a better response rate in patients with visceral metastases. However, a shorter duration of response and toxicity profile of erdafitinib, particularly ocular toxicity, is an important consideration. Regular eye exams are recommended by the FDA. Tumor profiling during upfront therapy may help identify those who benefit at the time of progression. In summary, a high unmet need remains for new drugs in chemotherapy- and ICI-refractory UC.

FGFR3S249C mutation promotes chemoresistance by activating Akt signaling in bladder cancer cells

Fibroblast growth factor receptor 3 (FGFR3) is a high frequency mutant gene in bladder cancer (BCa) and has become a promising therapeutic target due to its involvement in cell proliferation and migration. However, whether and how FGFR3 mutations affects BCa cell chemosensitivity is unknown. The current study aimed to elucidate the role of the FGFR3^S249C mutation in the development of chemoresistance in BCa cells. The results revealed that 97-7 (FGFR3^S249C) cells had decreased sensitivity to cisplatin compared with 5637 (FGFR3^WT) and T24 (FGFR3^WT) cells. The ratio of phosphorylated-Akt/total-Akt was higher in 97-7 (FGFR3^S249C) cells, which was reversed by knockdown of FGFR3. Furthermore, inhibition of Akt signaling by GDC0068 or LY294002 increased the cisplatin sensitivity of 97-7 (FGFR3^S249C) cells. GDC0068 or LY294002 was also revealed to augment the effects of cisplatin on 97-7 (FGFR3^S249C) cell proliferation and apoptosis. The results of the present study demonstrated that the FGFR3^S249C mutation promotes chemoresistance in BCa cells by activating the Akt signaling pathway. The FGFR3^S249C mutation may therefore be used as a predictor of chemosensitivity in patients with BCa.

Role of FGFR3 in Urothelial Carcinoma

BACKGROUND AND OBJECTIVE

This study was undertaken to analyze the immunohistochemical expression of fibroblast growth factor receptor (FGFR3) in urothelial carcinoma and correlate its expression with the pathological stage, recurrence and other clinicopathological parameters.

MATERIAL AND METHODS

A retrospective study was undertaken on paraffin blocks of 55consecutiveurothelial carcinoma specimens in 28 months received in Sri Ramachandra Medical College, Chennai, India. Blocks with the sections containing the tumor and adjacent normal epithelium were chosen for the immunohistochemical (IHC) study of FGFR3.

RESULTS

IHC expression of FGFR3 in high grade (HG) invasive urothelial carcinoma was positive in 18% cases, 66.7% of HG non-invasive urothelial and 82.6% of low grade (LG) non-invasive urothelial carcinomas. The FGFR3 expression was presented in 78.1% of non-invasive carcinoma. In case of invasive urothelial carcinoma, the FGFR3 positivity was observed in 18.2% of tumors (P<0.05).FGFR3 expression in LG tumors was positive in 82.6 % of the cases whereas 32.3% of HG cases were positive for FGFR3 (P<0.05).FGFR3 was expressed in 14.3 % of HG invasive tumors which recurred. HG non-invasive tumors were positive for FGFR3 in 80% of the cases. LG non-invasive tumors were positive for FGFR3 in 72.7% of cases (P<0.05).

CONCLUSION

The expression of FGFR3 is higher in low grade, non-invasive tumors and recurrent non-invasive tumors. The targeted therapy for FGFR3 may be used as one of the modes of treatment for urothelial carcinoma. It can also be used as a marker to determine the grade in difficult cases and the risk of recurrence.

Circular RNA hsa_circ_0068871 regulates FGFR3 expression and activates STAT3 by targeting miR-181a-5p to promote bladder cancer progression

BACKGROUND

FGFR3 plays an important role in the development of bladder cancer (BCa). Hsa_circ_0068871 is a circRNA generated from several exons of FGFR3. However, the potential functional role of hsa_circ_0068871 in BCa remains largely unknown. Here we aim to evaluate the role of hsa_circ_0068871 in BCa.

METHODS

We selected miR-181a-5p as the potential target miRNA of hsa_circ_0068871. The expression levels of hsa_circ_0068871 and miR-181a-5p were examined in BCa tissues and paired adjacent normal tissues by quantitative real-time PCR. To characterize the function of hsa_circ_0068871, BCa cell lines were stably infected with lentivirus targeting hsa_circ_0068871, followed by examinations of cell proliferation, migration and apoptosis. In addition, xenografts experiment in nude mice were performed to evaluate the effect of hsa_circ_0068871 in BCa. Biotinylated RNA probe pull-down assay, fluorescence in situ hybridization and luciferase reporter assay were conducted to confirm the relationship between hsa_circ_0068871, miR-181a-5p and FGFR3.

RESULTS

Hsa_circ_0068871 is over-expressed in BCa tissues and cell lines, whereas miR-181a-5p expression is repressed. Depletion of has_circ_0068871 or upregulation of miR-181a-5p inhibited the proliferation and migration of BCa cells in vitro and in vivo. Mechanistically, hsa_circ_0068871 upregulated FGFR3 expression and activated STAT3 by targeting miR-181a-5p to promote BCa progression.

CONCLUSIONS

Hsa_circ_0068871 regulates the miR-181a-5p/FGFR3 axis and activates STAT3 to promote BCa progression, and it may serve as a potential biomarker.

Targeting 3D Bladder Cancer Spheroids with Urease-Powered Nanomotors

Cancer is one of the main causes of death around the world, lacking efficient clinical treatments that generally present severe side effects. In recent years, various nanosystems have been explored to specifically target tumor tissues, enhancing the efficacy of cancer treatment and minimizing the side effects. In particular, bladder cancer is the ninth most common cancer worldwide and presents a high survival rate but serious recurrence levels, demanding an improvement in the existent therapies. Here, we present urease-powered nanomotors based on mesoporous silica nanoparticles that contain both polyethylene glycol and anti-FGFR3 antibody on their outer surface to target bladder cancer cells in the form of 3D spheroids. The autonomous motion is promoted by urea, which acts as fuel and is inherently present at high concentrations in the bladder. Antibody-modified nanomotors were able to swim in both simulated and real urine, showing a substrate-dependent enhanced diffusion. The internalization efficiency of the antibody-modified nanomotors into the spheroids in the presence of urea was significantly higher compared with antibody-modified passive particles or bare nanomotors. Furthermore, targeted nanomotors resulted in a higher suppression of spheroid proliferation compared with bare nanomotors, which could arise from the local ammonia production and the therapeutic effect of anti-FGFR3. These results hold significant potential for the development of improved targeted cancer therapy and diagnostics using biocompatible nanomotors.

14-3-3ζ promotes gliomas cells invasion by regulating Snail through the PI3K/AKT signaling

14-3-3ζ has been reported to function as critical regulators of diverse cellular responses. However, the role of 14-3-3ζ in gliomas progression remains largely unknown. The expression level of 14-3-3ζ and Snail was detected by Western blot analysis and quantitative polymerase chain reaction in different grades of human gliomas. The effect of 14-3-3ζ on gliomas progression was measured using cell migration and invasion assay, the colony formation experiment, and CCK-8 assay. The effect of 14-3-3ζ on PI3K/AKT/Snail signaling protein expression levels was tested by Western blotting. Firstly, 14-3-3ζ was often up-regulated in high-grade gliomas relative to low-grade gliomas, and this overexpression was significantly related to tumor size, Karnofsky Performance Scale score and weaker disease-free survival. Secondly, the overexpression of 14-3-3ζ promoted gliomas cells proliferation, migration, and invasion. Conversely, the knockdown of 14-3-3ζ suppressed gliomas cells proliferation, migration, and invasion. Furthermore, subsequent mechanistic studies showed that 14-3-3ζ could activate PI3K/AKT/Snail signaling pathway to facilitate gliomas cells proliferation, migration, and invasion. This study shows that the overexpression of 14-3-3ζ can promote remarkably gliomas cells proliferation, migration, and invasion by regulating the Snail protein expression through activating PI3K/AKT signaling, and it may serve as a potential prognostic marker and therapeutic target for gliomas.

Emerging biomarkers for the diagnosis and monitoring of urothelial carcinoma

Urothelial carcinoma (UC) arises extensively from the renal pelvis, ureter, urinary bladder, and urethra. UC represents a clinical and social challenge because of its incidence, post-treatment recurrence rate, and prognosis. Combinations of urine cytology, cystoscopy, and conventional imaging such as computed tomography are currently used for diagnosis and monitoring modalities of UC. Both the poor diagnostic accuracy of urine cytology and poor cost performance of cystoscopy and conventional imaging modalities emphasize the urgent need for advancement in clinical guidance for UC. Urine- and blood-based biomarkers for detection of UC of the bladder and upper urinary tract represent a considerable research area. Biomarkers can help to improve UC diagnosis with the aim of replacing cystoscopy and other imaging examinations in future and may enable individualizing risk stratification regarding therapy and follow-up. Over the decades, numerous studies have focused on the potential application of biomarkers for UC, including urine, circulating tumor DNA, RNAs, proteins, and extracellular vesicles. Although some biomarkers such as ImmunoCyt/uCyt+, UroVysion, NMP-22, bladder tumor antigen, CxBladder, and Xpert Bladder Cancer are currently available in clinical practice, few biomarkers achieve high sensitivity and specificity. Emerging biomarkers are continuously developed and reported in medical journals. However, there is a significant lack on following external validation using different cohorts. The positive results are needed to be confirmed by more studies with large-scale cohorts and long follow-up periods to prove the true value of novel biomarkers, followed by their adoption in clinical practice. The present paper provides an overview of the evidence based on high-impact studies regarding urine- and blood-based biomarkers and their clinical applications in bladder cancer and upper tract UC.

FGFR3 mutation increases bladder tumourigenesis by suppressing acute inflammation

Recent studies of muscle-invasive bladder cancer show that FGFR3 mutations are generally found in a luminal papillary tumour subtype that is characterised by better survival than other molecular subtypes. To better understand the role of FGFR3 in invasive bladder cancer, we examined the process of tumour development induced by the tobacco carcinogen OH-BBN in genetically engineered models that express mutationally activated FGFR3 S249C or FGFR3 K644E in the urothelium. Both occurrence and progression of OH-BBN-driven tumours were increased in the presence of an S249C mutation compared to wild-type control mice. Interestingly, at an early tumour initiation stage, the acute inflammatory response in OH-BBN-treated bladders was suppressed in the presence of an S249C mutation. However, at later stages of tumour progression, increased inflammation was observed in S249C tumours, long after the carcinogen administration had ceased. Early-phase neutrophil depletion using an anti-Ly6G monoclonal antibody resulted in an increased neutrophil-to-lymphocyte ratio at later stages of pathogenesis, indicative of enhanced tumour pathogenesis, which supports the hypothesis that suppression of acute inflammation could play a causative role. Statistical analyses of correlation showed that while initial bladder phenotypes in morphology and inflammation were FGFR3-dependent, increased levels of inflammation were associated with tumour progression at the later stage. This study provides a novel insight into the tumour-promoting effect of FGFR3 mutations via regulation of inflammation at the pre-tumour stage in the bladder. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Structural Alterations in Human Fibroblast Growth Factor Receptors in Carcinogenesis

Fibroblast growth factor (FGF) plays an important role in human embryogenesis, angiogenesis, cell proliferation, and differentiation. Carcinogenesis is accompanied by aberrant constitutive activation of FGF receptors (FGFRs) resulting from missense mutation in the FGFR1-4 genes, generation of chimeric oncogenes, FGFR1-4 gene amplification, alternative splicing shift toward formation of mesenchymal FGFR isoforms, and FGFR overexpression. Altogether, these alterations contribute to auto- and paracrine stimulation of cancer cells and neoangiogenesis. Certain missense mutations are found at a high rate in urinary bladder cancer and can be used for non-invasive cancer recurrence diagnostics by analyzing urine cell pellet DNA. Chimeric FGFR1/3 and amplified FGFR1/2 genes can predict cell response to the targeted therapy in various oncological diseases. In recent years, high-throughput sequencing has been used to analyze exomes of virtually all human tumors, which allowed to construct phylogenetic trees of clonal cancer evolution with special emphasis on driver mutations in FGFR1-4 genes. At present, FGFR blockers, such as multi-kinase inhibitors, specific FGFR inhibitors, and FGF ligand traps are being tested in clinical trials. In this review, we discuss current data on the functioning of the FGFR family proteins in both normal and cancer cells, mutations in the FGFR1-4 genes, and mechanisms underlying their oncogenic potential, which might be interesting to a broad range of scientists searching for specific tumor markers and targeted anti-cancer drugs.

Molecular investigation of FGFR3 gene mutation and its correlation with clinicopathological findings in Indian bladder cancer patients

BACKGROUND

Molecular alteration of FGFR3 gene is the most common genetic event currently known in bladder cancer. Notably, FGFR3 mutation has emerged as a promising molecular biomarker for recurrence, prognosis, and therapeutic target in bladder cancer.

AIM

The present study explored the frequency and distribution pattern of FGFR3 mutation in 100 Indian bladder cancer patients.

METHODS AND RESULTS

Exons 7, 10, and 15 were subjected to nested PCR followed by bidirectional sequencing of the PCR products. Overall, FGFR3 gene mutations were identified in 19 bladder cancer patients (19%, 19 of 100). Most of the mutations were noted in exon 7 (15%), followed by exon 10 (4%). All mutations detected were missense in nature affecting amino acids at codons 248, 249, and 373. The S249C mutations were the most recurrent mutation seen in exon 7, while Y373C was commonly observed in exon 10. In contrast to exons 7 and 10, no mutations were seen in exon 15 in this study. Females and older age patients tend to show increased frequency of FGFR3 mutations. Furthermore, FGFR3 mutations were more common in low pathological stage (6/20 pTa and 13/71 pT1) and low-grade tumors (13/46). This predominance in low-grade tumors were significantly high in comparison to high-grade tumor (P = .04). Likewise, FGFR3 mutations were significantly higher in well-differentiated tumors (32.6%, 14/43) in comparison to moderately differentiated tumors (11.3%, 5/44), and poorly differentiated tumor (0%, 0/13) (P = .007). No other association of FGFR3 with tumor size, necrosis, and variant histology was noted.

CONCLUSIONS

The current study highlights the spectrum of FGFR3 mutation in Indian patients, and the data presented here are similar to those reported from across the globe.

FGFR3 mRNA overexpression defines a subset of oligometastatic colorectal cancers with worse prognosis

Objectives

Metastatic colorectal cancer (CRC) remains a leading cause of cancer related deaths. Patients with oligometastatic liver disease represent a clinical subgroup with heterogeneous course. Until now, biomarkers to characterize outcome and therapeutic options have not been fully established.

Methods

We investigated the prevalence of FGFR alterations in a total of 140 primary colorectal tumors and 63 liver metastases of 55 oligometastatic CRC patients. FGF receptors (FGFR1-4) and their ligands (FGF3, 4 and 19) were analyzed for gene amplifications and rearrangements as well as for RNA overexpression in situ. Results were correlated with clinico-pathologic data and molecular subtypes.

Results

Primary tumors showed FGFR1 (6.3%) and FGF3,4,19 (2.2%) amplifications as well as FGFR1 (10.1%), FGFR2 (5.5%) and FGFR3 (16.2%) overexpression. In metastases, we observed FGFR1 amplifications (4.8%) as well as FGFR1 (8.5%) and FGFR3 (14.9%) overexpression. Neither FGFR2-4 amplifications nor gene rearrangements were observed. FGFR3 overexpression was significantly associated with shorter overall survival in metastases (mOS 19.9 vs. 47.4 months, HR=3.14, p=0.0152), but not in primary CRC (HR=1.01, p=0.985). Although rare, also FGFR1 amplification was indicative of worse outcome (mOS 12.6 vs. 47.4 months, HR=8.83, p=0.00111).

Conclusions

We provide the so far most comprehensive analysis of FGFR alterations in primary and metastatic CRC. We describe FGFR3 overexpression in 15% of CRC patients with oligometastatic liver disease as a prognosticator for poor outcome. Recently FGFR3 overexpression has been shown to be a potential therapeutic target. Therefore, we suggest focusing on this subgroup in upcoming clinical trials with FGFR-targeted therapies.

A Panel of MicroRNA Signature as a Tool for Predicting Survival of Patients with Urothelial Carcinoma of the Bladder

Introduction and Objectives

MicroRNA (miRNA) expression is altered in urologic malignancies, including urothelial carcinoma of the bladder (UCB). Individual miRNAs have been shown to modulate multiple signaling pathways that contribute to BC. To identify a panel of miRNA signature that can predict aggressive phenotype from normal nonaggressive counterpart using miRNA expression levels and to assess the prognostic value of this specific miRNA markers in patients with UCB.

Methods

To determine candidate miRNAs as prognostic biomarkers for dividing aggressive type of UCB, miRNA expression was profiled in patients' samples with an aggressive phenotype or nonaggressive phenotype using 3D-Gene miRNA labeling kit (Toray, Japan). To create a prognostic index model, we used the panel of 9-miRNA signature based on Cancer Genome Atlas (TCGA) data portal (TCGA Data Portal (https://tcgadata.nci.nih.gov/tcga/tcgaHome2.jsp)). miRNA expression data and corresponding clinical data, including outcome and staging information of 84 UCB patients, were obtained. The Kaplan-Meier and log-rank test were performed to quantify the survival functions in two groups.

Results

Deregulation of nine miRNAs (hsa-miR-99a-5p, hsa-miR-100-5p, hsa-miR-125b-5p, hsa-miR-145-5p, hsa-miR-4324, hsa-miR-34b-5p, hsa-miR-29c-3p, hsa-miR-135a-3p, and hsa-miR-33b-3p) was determined in UCB patients with aggressive phenotype compared with nonaggressive subject. To validate the prognostic power of the nine-signature miRNAs using the TCGA dataset of bladder cancer, the survival status and tumor miRNA expression of all 84 TCGA UCB patients were ranked according to the prognostic score values. Of nine miRNAs, six were associated with high risk (hsa-miR-99a-5p, hsa-miR-100-5p, hsa-miR-125b-5p, hsa-miR-4324, hsa-miR-34b-5p, and hsa-miR-135a-3p) and three were shown to be protective (hsa-miR-145-5p, hsa-miR-29c-3p, and hsa-miR-33b-3p). Patients with the high-risk miRNA signature exhibited poorer OS than patients expressing the low-risk miRNA profile (HR = 7.05, p < 0.001).

Conclusions

The miRNA array identified nine dysregulated miRNAs from clinical samples. This panel of nine-miRNA signature provides predictive and prognostic value of patients with UCB.

The New Age of -omics in Urothelial Cancer - Re-wording Its Diagnosis and Treatment

Unmet needs in urothelial cancer management represent an important challenge in our effort to improve long-term overall and disease-free survival rates with no significant compromise in quality of life. Radical cystectomy with pelvic lymph node dissection is the standard for the management of muscle-invasive, non-metastatic cancers. In spite of a 90% local disease control, up to 50% of patients ultimately die of distant metastasis. Bladder preservation using chemo-radiation is an acceptable alternative, but optimal patient selection remains elusive. Recent research is focused on the employment of tailored-made strategies in urothelial cancer exploiting the potential of theranostics in patient selection for specific therapies. Herein, we review the current knowledge on molecular theranostics in urothelial cancer and we suggest that this is the time to move toward imaging theranostics, if tailored-made disease management and patient stratification is envisaged.

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Urothelial cancer management represents an important challenge.

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Optimum patient stratification and tailored-made theranostics remain elusive.

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Imaging theranostics is envisaged as a cancer roadmap.

Differential Expression of FGFRs Signaling Pathway Components in Bladder Cancer: A Step Toward Personalized Medicine

Variations Improper activation and inappropriate expression of fibroblast growth factor receptors (FGFRs) in cancer suggests that they can act as therapeutic targets. Fibroblast growth factor receptor inhibitors are currently employed in clinical trials of different cancers. Regarding the essence and the importance of the personalized medicine, mainly mirrored by remarkable inter-individual variations in different populations, we aimed to perform a pilot study to address FGFR1 and FGFR3 expression levels and their correlation with the clinicopathological features in Iranian patients with bladder cancer (BC). Paired tumor and adjacent non tumor tissue samples along with their clinico-pathological parameters were obtained from 50 cases diagnosed with BC in different stages and grades. The mRNA expressions of FGFR1 and FGFR3 in tissue samples were determined by real-time polymerase chain reaction (real-time PCR). The expression levels of FGFR3 were significantly higher in tumor tissues when compared to adjacent normal tissues (p = 0.007), regardless of the stages and grades of the tumor. Over expression was associated with cigarette smoking (p = 0.037) and family history for cancer (p = 0.004). Decreased expression of FGFR1 was observed, remarkably evident in high-grade tumors (p = 0.047), while over expression was detected in low-grade samples. This pilot study clearly suggests that in Iranian BC patients FGFR1 and FGFR3 expression patterns are different, and also highly distinctive with regard to the tumor’s stage and grade. Such particular expression patterns may indicate their special values to be employed for interventional studies aiming targeted therapy. Further studies with a larger sample size are needed to validate our results.

Role of Non-Coding RNAs in the Etiology of Bladder Cancer

According to data of the International Agency for Research on Cancer and the World Health Organization (Cancer Incidence in Five Continents, GLOBOCAN, and the World Health Organization Mortality), bladder is among the top ten body locations of cancer globally, with the highest incidence rates reported in Southern and Western Europe, North America, Northern Africa and Western Asia. Males (M) are more vulnerable to this disease than females (F), despite ample frequency variations in different countries, with a M:F ratio of 4.1:1 for incidence and 3.6:1 for mortality, worldwide. For a long time, bladder cancer was genetically classified through mutations of two genes, fibroblast growth factor receptor 3 (FGFR3, for low-grade, non-invasive papillary tumors) and tumor protein P53 (TP53, for high-grade, muscle-invasive tumors). However, more recently scientists have shown that this disease is far more complex, since genes directly involved are more than 150; so far, it has been described that altered gene expression (up- or down-regulation) may be present for up to 500 coding sequences in low-grade and up to 2300 in high-grade tumors. Non-coding RNAs are essential to explain, at least partially, this ample dysregulation. In this review, we summarize the present knowledge about long and short non-coding RNAs that have been linked to bladder cancer etiology.

Safety, pharmacokinetic, and pharmacodynamics of erdafitinib, a pan-fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor, in patients with advanced or refractory solid tumors

Introduction This phase 1, open-label, multicenter, single-arm, dose-escalation study aimed to evaluate safety, pharmacokinetics (PK), and pharmacodynamics of erdafitinib (JNJ-42756493), an oral selective pan-fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor, and to determine the recommended phase 2 dose in Japanese patients with advanced or refractory solid tumors. Methods Three to 6 patients were enrolled into sequentially escalating dose cohorts (erdafitinib 2, 4, or 6 mg) with a daily dosing schedule of 21-day cycles or a 7 days-on/7 days-off intermittent schedule (erdafitinib 10 mg or 12 mg) of 28-day cycles. Results Nineteen patients received escalating doses of erdafitinib with a daily or intermittent schedule. The most common treatment-emergent adverse events (TEAEs) were hyperphosphatemia (73.7%), nausea (36.8%), stomatitis (26.3%), dysgeusia (26.3%) and dry mouth (21.1%). The maximum tolerated dose was not reached in this study. No Grade 3 or higher TEAEs, or serious TEAEs were noted and no clinically significant changes in vital signs, laboratory parameters, and electrocardiogram readings were observed. However, one case of dose-limiting toxicity in the 12 mg intermittent dosing group was observed: Grade 2 detachment of retinal pigment epithelium (bilateral) with treatment discontinuation. The maximum plasma concentrations of erdafitinib exhibited a dose-dependent increase. The median t_max ranged from 2 to 3 h after the initial dose to 2-6 h following multiple daily dosing. Based on the safety and PK data, the 10 mg 7 days-on/7 days-off regimen was determined as the recommended phase 2 dose in this study. Conclusions Erdafitinib was well tolerated in Japanese patients with advanced or refractory solid tumors.

TRIAL REGISTRATION

NCT01962532.

Expression levels of FGFR3 as a prognostic marker for the progression of primary pT1 bladder cancer and its association with mutation status

The present study examined the utility of fibroblast growth factor receptor 3 (FGFR3) mutation status and gene expression as a prognostic marker in primary pT1 bladder cancer (BC). A total of 120 patients with primary pT1 BC were enrolled. FGFR3 mutation status was determined by direct sequencing and FGFR3 mRNA expression level was determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis. The results were compared with the clinicopathological parameters, and the prognostic value of FGFR3 was evaluated by Kaplan-Meier analysis and a multivariate Cox regression test. FGFR3 mutations were identified in 48/120 (40.0%) patients with pT1 BC. FGFR3 mRNA expression level was significantly higher in those with BC harboring FGFR3 mutations (P<0.001). Low FGFR3 expression level was associated with high-grade tumors and cancer progression (P=0.006 and P=0.001), whereas FGFR3 mutation status was not associated with cancer progression. Kaplan-Meier analysis revealed a similar result (log-rank, P<0.001). Multivariate analysis identified low FGFR3 expression level (odds ratio, 3.300; 95% confidence interval, 1.310-8.313; P=0.011) as an independent predictor of cancer progression. Stratification by exon site of FGFR3 mutations yielded significant differences in mRNA expression level. None of the patients with BC harboring FGFR3 mutations in exon 9 demonstrated disease progression. The mRNA expression level of the FGFR3 gene may be used to precisely identify subsets of patients with pT1 BC that have a relatively better prognosis. The prognostic influences of FGFR3 mutations may be modulated by the exon site of FGFR3 mutations.