Targeting fibroblast growth factor receptors and immune checkpoint inhibitors for the treatment of advanced bladder cancer: New direction and New Hope

Erdafitinib promotes ferroptosis in human uveal melanoma by inducing ferritinophagy and lysosome biogenesis via modulating the FGFR1/mTORC1/TFEB signaling axis

Uveal melanoma (UM) is a rare yet lethal primary intraocular malignancy affecting adults. Analysis of data from The Cancer Genome Atlas (TCGA) database revealed that FGFR1 expression was increased in UM tumor tissues and was linked to aggressive behavior and a poor prognosis. This study assessed the anti-tumor effects of Erdafitinib, a selective pan-FGFR inhibitor, in both in vitro and in vivo UM models. Erdafitinib exhibited a robust anti-cancer activity in UM through inducing ferroptosis in the FGFR1-dependent manner. Transcriptomic data revealed that Erdafitinib mediated its anti-cancer effects via modulating the ferritinophagy/lysosome biogenesis. Subsequent research revealed that Erdafitinib exerted its effects by reducing the expression of FGFR1 and inhibiting the activity of mTORC1 in UM cells. Concurrently, it enhanced the dephosphorylation, nuclear translocation, and transcriptional activity of TFEB. The aggregation of TFEB in nucleus triggered FTH1-dependent ferritinophagy, leading to lysosomal activation and iron overload. Conversely, the overexpression of FGFR1 served to mitigate the effects of Erdafitinib on ferritinophagy, lysosome biogenesis, and the activation of the mTORC1/TFEB signaling pathway. In vivo experiments have convincingly shown that Erdafitinib markedly curtails tumor growth in an UM xenograft mouse model, an effect that is closely correlated with a decrease in FGFR1 expression levels. The present study is the first to demonstrate that Erdafitinib powerfully induces ferroptosis in UM by orchestrating the ferritinophagy and lysosome biogenesis via modulating the FGFR1/mTORC1/TFEB signaling. Consequently, Erdafitinib emerges as a strong candidate for clinical trial investigation, and FGFR1 emerges as a novel and promising therapeutic target in the treatment of UM.

Mathematical Modeling of Tumor Immune Interactions: The Role of Anti-FGFR and Anti-PD-1 in the Combination Therapy

Bladder cancer poses a significant global health burden with high incidence and recurrence rates. This study addresses the therapeutic challenges in advanced bladder cancer, focusing on the competitive mechanisms of ligand or drug binding to receptors. We developed a refined mathematical model that integrates the dynamics of tumor cells and immune responses, particularly targeting fibroblast growth factor receptor 3 (FGFR3) and immune checkpoint inhibitors (ICIs). This study contributes to understanding combination therapies by elucidating the competitive binding dynamics and quantifying the synergistic effects. The findings highlight the importance of personalized immunotherapeutic strategies, considering factors such as drug dosage, dosing schedules, and patient-specific parameters. Our model further reveals that ligand-independent activated-state receptors are the most essential drivers of tumor proliferation. Moreover, we found that PD-L1 expression rate was more important than PD-1 in driving the dynamic evolution of tumor and immune cells. The proposed mathematical model provides a comprehensive framework for unraveling the complexities of combination therapies in advanced bladder cancer. As research progresses, this multidisciplinary approach contributes valuable insights toward optimizing therapeutic strategies and advancing cancer treatment paradigms.

Single-cell transcriptomic analysis of tumor heterogeneity and intercellular networks in human urothelial carcinoma

BACKGROUND

Heterogeneity of tumor cells and the tumor microenvironment (TME) is significantly associated with clinical outcomes and treatment responses in patients with urothelial carcinoma (UC). Comprehensive profiling of the cellular diversity and interactions between malignant cells and TME may clarify the mechanisms underlying UC progression and guide the development of novel therapies. This study aimed to extend our understanding of intra-tumoral heterogeneity and the immunosuppressive TME in UC and provide basic support for the development of novel UC therapies.

METHODS

Seven patients with UC were included who underwent curative surgery at our hospital between July 2020 and October 2020. We performed single-cell RNA sequencing (scRNA-seq) analysis in seven tumors with six matched adjacent normal tissues and integrated the results with two public scRNA-seq datasets. The functional properties and intercellular interactions between single cells were characterized, and the results were validated using multiplex immunofluorescence staining, flow cytometry, and bulk transcriptomic datasets. All statistical analyses were performed using the R package with two-sided tests. Wilcoxon-rank test, log-rank test, one-way analysis of variance test, and Pearson correlation analysis were used properly.

RESULTS

Unsupervised t-distributed stochastic neighbor embedding clustering analysis identified ten main cellular subclusters in urothelial tissues. Of them, seven urothelial subtypes were noted, and malignant urothelial cells were characterized with enhanced cellular proliferation and reduced immunogenicity. CD8 + T cell subclusters exhibited enhanced cellular cytotoxicity activities along with increased exhaustion signature in UC tissues, and the recruitment of CD4 + T regulatory cells was also increased in tumor tissues. Regarding myeloid cells, coordinated reprogramming of infiltrated neutrophils, M2-type polarized macrophages, and LAMP3 + dendritic cells contribute to immunosuppressive TME in UC tissues. Tumor tissues demonstrated enhanced angiogenesis mediated by KDR + endothelial cells and RGS5 + /ACTA2 + pericytes. Through deconvolution analysis, we identified multiple cellular subtypes may influence the programmed death-ligand 1 (PD-L1) immunotherapy response in patients with UC.

CONCLUSION

Our scRNA-seq analysis clarified intra-tumoral heterogeneity and delineated the pro-tumoral and immunosuppressive microenvironment in UC tissues, which may provide novel therapeutic targets.

An enhancer RNA-based risk model for prediction of bladder cancer prognosis

Background

Bladder cancer patients have a high recurrence and poor survival rates worldwide. Early diagnosis and intervention are the cornerstones for favorable prognosis. However, commonly used predictive tools cannot meet clinical needs because of their insufficient accuracy.

Methods

We have developed an enhancer RNA (eRNA)-based signature to improve the prediction for bladder cancer prognosis. First, we analyzed differentially expressed eRNAs in gene expression profiles and clinical data for bladder cancer from The Cancer Genome Atlas database. Then, we constructed a risk model for prognosis of bladder cancer patients, and analyzed the correlation between this model and tumor microenvironment (TME). Finally, regulatory network of downstream genes of eRNA in the model was constructed by WGCNA and enrichment analysis, then Real-time quantitative PCR verified the differentiation of related genes between tumor and adjacent tissue.

Results

We first constructed a risk model composed of eight eRNAs, and found the risk model could be an independent risk factor to predict the prognosis of bladder cancer. Then, the log-rank test and time-dependent ROC curve analysis shown the model has a favorable ability to predict prognosis. The eight risk eRNAs may participate in disease progression by regulating cell adhesion and invasion, and up-regulating immune checkpoints to suppress the immunity in TME. mRNA level change in related genes further validated regulatory roles of eRNAs in bladder cancer. In summary, we constructed an eRNA-based risk model and confirmed that the model could predict the prognosis of bladder cancer patients.

Advances in Diagnosis and Therapy for Bladder Cancer

Simple Summary

The clinical management of bladder cancer has been developing in the past decade, including diagnostic tools and treatment options. Both monotherapy and combination therapy have been undoubtedly upgraded. Multiple diagnostic techniques and therapeutic strategies have been developed to meet the urgent clinical needs, resulting in the emergence of various explorations for cancer diagnosis and therapy. In this review, we mainly focus on the advances in the diagnosis and treatment of bladder cancer.

Abstract

Bladder cancer (BCa) is one of the most common and expensive urinary system malignancies for its high recurrence and progression rate. In recent years, immense amounts of studies have been carried out to bring a more comprehensive cognition and numerous promising clinic approaches for BCa therapy. The development of innovative enhanced cystoscopy techniques (optical techniques, imaging systems) and tumor biomarkers-based non-invasive urine screening (DNA methylation-based urine test) would dramatically improve the accuracy of tumor detection, reducing the risk of recurrence and progression of BCa. Moreover, intravesical instillation and systemic therapeutic strategies (cocktail therapy, immunotherapy, vaccine therapy, targeted therapy) also provide plentiful measures to break the predicament of BCa. Several exploratory clinical studies, including novel surgical approaches, pharmaceutical compositions, and bladder preservation techniques, emerged continually, which are supposed to be promising candidates for BCa clinical treatment. Here, recent advances and prospects of diagnosis, intravesical or systemic treatment, and novel drug delivery systems for BCa therapy are reviewed in this paper.

Erdafitinib in locally advanced/metastatic urothelial carcinoma with certain FGFR genetic alterations

FGFR inhibitors represent a new and promising therapeutic approach to urothelial cancer (UC). Erdafitinib (Balversa^©) was the first FGFR inhibitor approved for the treatment of metastatic UC, showing proper pharmacological activity and a consistent safety profile in a population with limited or no therapeutic alternatives. While results from comparative phase II and III trials are needed to assess the efficacy of erdafitinib in different clinical settings, there are still questions unsolved regarding a typical class effect of FGFR inhibitors, hyperphosporemia. In this review, the authors focus on the state-of-art administration of erdatifinib in advanced UC, pointing out the more recent evidence, pitfalls and possible future research. Insight on the management of hyperphosporemia in patients undergoing treatment with FGFR inhibitors is also provided.

circ-FNTA accelerates proliferation and invasion of bladder cancer

Role of circ-FNTA in the progression of bladder cancer (BCa) and its underlying mechanism were investigated. circ-FNTA level in BCa tissues and cell lines was detected. The prognostic potential of circ-FNTA was assessed by Kaplan-Meier methods and the proliferative and invasive abilities of BCa influenced by circ-FNTA were explored. Through dual-luciferase reporter gene assay, miRNA-451a, the target of circ-FNTA and the target gene of miRNA-451a, S1PR3 were determined. circ-FNTA was upregulated in BCa, especially in invasive BCa. High level of circ-FNTA indicated worse prognosis in BCa patients. Silence of circ-FNTA attenuated the proliferative and invasive abilities of T24 and UM-UC-3 cells. miRNA-451a was verified to be the target of circ-FNTA, which was downregulated in BCa cells. circ-FNTA negatively regulated the expression level of miRNA-451a. Moreover, S1PR3 was the downstream gene of miRNA-451a. Overexpression of miRNA-451a downregulated S1PR3 level in BCa cells. circ-FNTA accelerates the proliferative and invasive abilities of BCa through targeting miRNA-451a/S1PR3 axis, and indicates a poor prognosis of BCa patients.

Sulfated polysaccharide of Sepiella maindroni ink targets Akt and overcomes resistance to the FGFR inhibitor AZD4547 in bladder cancer

Rapid appearance of resistance to fibroblast growth factor receptor (FGFR) inhibitors hampers targeted regimens in bladder cancer. In the present study, we evaluated whether SIP-SII, a sulphated derivative of the polysaccharide in Sepiella maindroni (spineless cuttlefish) ink used in traditional Chinese medicine, could attenuate resistance to FGFR inhibition in bladder cancer cells. In vitro assays indicated that SIP-SII reduced cell viability and migration, restricted cell cycle progression, and increased apoptosis in parallel with decreased AKT phosphorylation and downregulation of CDK4, MMP2, and Bcl-2 in RT112 and JMSU1 cells. Synergistic effects on cell viability were observed when SIP-SII was combined with the small-molecule FGFR inhibitor AZD4547. Specific Akt targeting by SIP-SII was suggested by the fact that neither Akt knockdown nor the selective PI3K inhibitor BKM120 enhanced the inhibitory effects of SIP-II, while expression of a constitutively active Akt mutant rescued SIP-SII effects. Furthermore, subcutaneous transplantation of RT112 xenografts confirmed the superiority and tolerability of combined SIP-SII and AZD4547 administration over monotherapy regimens. The present study thus provides pre-clinical evidence of the ability of SIP-SII to improve FGFR-targeted therapies for bladder cancer by inhibiting Akt.

Hope and challenge: Precision medicine in bladder cancer

Bladder cancer (BC) is a complex disease and could be classified into nonmuscle‐invasive BC (NMIBC) or muscle‐invasive BC (MIBC) subtypes according to the distinct genetic background and clinical prognosis. Until now, the golden standard and confirmed diagnosis of BC is cystoscopy and the major problems of BC are the high rate of recurrence and high costs in the clinic. Recent molecular and genetic studies have provided perspectives on the novel biomarkers and potential therapeutic targets of BC. In this article, we provided an overview of the traditional diagnostic approaches of BC, and introduced some new imaging, endoscopic, and immunological diagnostic technology in the accurate diagnosis of BC. Meanwhile, the minimally invasive precision treatment technique, immunotherapy, chemotherapy, gene therapy, and targeted therapy of BC were also included. Here, we will overview the diagnosis and therapy methods of BC used in clinical practice, focusing on their specificity, efficiency, and safety. On the basis of the discussion of the benefits of precision medicine in BC, we will also discuss the challenges and limitations facing the non‐invasive methods of diagnosis and precision therapy of BC. The molecularly targeted and immunotherapeutic approaches, and gene therapy methods to BC treatment improved the prognosis and overall survival of BC patients.

Rogaratinib: A potent and selective pan-FGFR inhibitor with broad antitumor activity in FGFR-overexpressing preclinical cancer models

Aberrant activation in fibroblast growth factor signaling has been implicated in the development of various cancers, including squamous cell lung cancer, squamous cell head and neck carcinoma, colorectal and bladder cancer. Thus, fibroblast growth factor receptors (FGFRs) present promising targets for novel cancer therapeutics. Here, we evaluated the activity of a novel pan‐FGFR inhibitor, rogaratinib, in biochemical, cellular and in vivo efficacy studies in a variety of preclinical cancer models. In vitro kinase activity assays demonstrate that rogaratinib potently and selectively inhibits the activity of FGFRs 1, 2, 3 and 4. In line with this, rogaratinib reduced proliferation in FGFR‐addicted cancer cell lines of various cancer types including lung, breast, colon and bladder cancer. FGFR and ERK phosphorylation interruption by rogaratinib treatment in several FGFR‐amplified cell lines suggests that the anti‐proliferative effects are mediated by FGFR/ERK pathway inhibition. Furthermore, rogaratinib exhibited strong in vivo efficacy in several cell line‐ and patient‐derived xenograft models characterized by FGFR overexpression. The observed efficacy of rogaratinib strongly correlated with FGFR mRNA expression levels. These promising results warrant further development of rogaratinib and clinical trials are currently ongoing (ClinicalTrials.gov Identifiers: NCT01976741, NCT03410693, NCT03473756).

What's new?

Deregulated fibroblast growth factor receptor (FGFR) signaling is involved in tumorigenesis and cancer progression. Here, the authors report on a novel pan‐FGFR inhibitor, rogaratinib, that potently and highly selectively prevents the activity of FGFRs 1, 2, 3, and 4. Rogaratinib inhibits cell proliferation in various FGFR‐addicted cancers in vitro, including colon, lung, and bladder cancer. Rogaratinib also exhibits strong in vivo efficacy in several cell line‐ and patient‐derived xenograft models characterized by FGFR mRNA overexpression with good tolerability. Altogether, these data warrant the further development of rogaratinib for treatment of cancers with FGFR alterations, and clinical trials are currently ongoing.

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.

HDAC inhibition as a treatment concept to combat temsirolimus-resistant bladder cancer cells

Introduction

Although the mechanistic target of rapamycin (mTOR) might be a promising molecular target to treat advanced bladder cancer, resistance develops under chronic exposure to an mTOR inhibitor (everolimus, temsirolimus). Based on earlier studies, we proposed that histone deacetylase (HDAC) blockade might circumvent resistance and investigated whether HDAC inhibition has an impact on growth of bladder cancer cells with acquired resistance towards temsirolimus.

Results

The HDAC inhibitor valproic acid (VPA) significantly inhibited growth, proliferation and caused G0/G1 phase arrest in RT112^res and UMUC-3^res. cdk1, cyclin B, cdk2, cyclin A and Skp1 p19 were down-regulated, p27 was elevated. Akt-mTOR signaling was deactivated, whereas acetylation of histone H3 and H4 in RT112^res and UMUC-3^res increased in the presence of VPA. Knocking down cdk2 or cyclin A resulted in a significant growth blockade of RT112^res and UMUC-3^res.

Materials And Methods

Parental (par) and resistant (res) RT112 and UMUC-3 cells were exposed to the HDAC inhibitor VPA. Tumor cell growth, proliferation, cell cycling and expression of cell cycle regulating proteins were then evaluated. siRNA blockade was used to investigate the functional impact of the proteins.

Conclusions

HDAC inhibition induced a strong response of temsirolimus-resistant bladder cancer cells. Therefore, the temsirolimus-VPA-combination might be an innovative strategy for bladder cancer treatment.

Comparison of Fibroblast Growth-factor Receptor Gene Alterations at the DNA versus Messenger RNA Level in Advanced Urothelial Cancer: Insights for Clinical Research

Pan-fibroblast growth-factor receptor (FGFR) inhibitors hold promise in FGFR-altered patients, but such alterations are rare in advanced urothelial carcinoma. In order to assess whether we may increase the number of eligible patients by using different molecular techniques for detecting alterations, we pooled the results of the centralised FGFR mutation/translocation assays that were performed in Clinical Laboratory Improvement Amendments-certified laboratories within multiple phase 2 trials. At our centre, the same tissue blocks were used to analyse FGFR1-3 messenger RNA expression through messenger RNA in situ hybridisation (ISH; RNAscope 2.5 assay). From October 2016 to March 2017, 52 cases were analysed. Seventeen patients (32.7%) had an upper tract primary tumour. Ten patients (19.2%) had FGFR DNA alterations. Twenty-nine (55.8%) had positive ISH analysis: N=17 score 3, N=12 score 4. Of note, concordance between the two tests was obtained in seven out of 10 patients. Sixty percent of mutated patients had an upper tract primary tumour versus 31% of ISH-positive patients. PATIENT SUMMARY: We found three-fold higher frequency of fibroblast growth-factor receptor alterations at the RNA versus DNA level in advanced urothelial carcinoma, with a different distribution according to the method used and the site of the primary tumour. The evaluation of the therapeutic response to pan-fibroblast growth-factor receptor inhibitors according to the method of assessment is warranted.

Systemic chemotherapy in muscle invasive and metastatic bladder cancer: present and future

Bladder cancer is the most frequent among the urothelial tumors, and it is responsible for about 2% of all cancer mortality worldwide. The mainstay of chemotherapy treatment, both for muscle-invasive and metastatic disease, is cisplatin-based regimens. In recent years, ground-breaking results have been achieved with immunotherapy, which have led to important breakthroughs in the bladder cancer treatment scenario, with the approval of several new agents. New insights derive from a greater characterization of the tumor genome, which could lead to developing new therapies, more personalized, in the near future.

Efficacy of post-nephroureterectomy cisplatin-based adjuvant chemotherapy for locally advanced upper tract urothelial carcinoma: a multi-institutional retrospective study

PURPOSE

To evaluate the efficacy of adjuvant systemic chemotherapy for locally advanced (pT3-4pN0/xM0) upper tract urothelial carcinoma (UTUC).

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 109 patients with pT3-4pN0/xM0 UTUC who had undergone radical nephroureterectomy between 1996 and 2013 at our four institutions. The patients were divided into two groups: those who received adjuvant chemotherapy (AC group) and those who did not (surgery-alone: SA group). All chemotherapy regimens were cisplatin-based. Cox proportional hazards regression models addressed the associations between clinicopathological factors and recurrence-free survival (RFS) and cancer-specific survival (CSS).

RESULTS

Forty-three (39.5%) out of the 109 patients underwent one to four cycles of adjuvant chemotherapy after nephroureterectomy. Median follow-up was 46.5 months. There were no significant differences in the background characteristics of the two groups, except for age. Recurrence developed in 11 (25.6%) and 29 (43.9%) patients in the AC and SA groups, respectively. Ultimately, six (14.0%) and 18 (27.3%) patients in the AC and SA groups, respectively, died of disease progression. On univariate analysis, hydronephrosis, nuclear grade, lymphovascular invasion, and adjuvant chemotherapy were significantly associated with both RFS and CSS. Charlson comorbidity index was associated only with CSS. On multivariate analysis, adjuvant chemotherapy was the only independent factor associated with improved RFS (p = 0.0178, HR = 0.41). Moreover, adjuvant chemotherapy (p = 0.0375, HR = 0.33), lower nuclear grade (p = 0.0070), and the absence of hydronephrosis (p = 0.0493) were independently associated with better CSS.

CONCLUSION

Locally advanced (pT3-4pN0/xM0) UTUC patients who underwent cisplatin-based adjuvant chemotherapy demonstrated better RFS and CSS than those without adjuvant chemotherapy.