Targeted therapies in urothelial bladder cancer: a disappointing past preceding a bright future?

Dual-Temperature/pH-Sensitive Hydrogels with Excellent Strength and Toughness Crosslinked Using Three Crosslinking Methods

Hydrogels are widely used as excellent drug carriers in the field of biomedicine. However, their application in medicine is limited by their poor mechanical properties and softness. To improve the mechanical properties of hydrogels, a novel triple-network amphiphilic hydrogel with three overlapping crosslinking methods using a one-pot free-radical polymerization was synthesized in this study. Temperature-sensitive and pH-sensitive monomers were incorporated into the hydrogel to confer stimulus responsiveness, making the hydrogel stimuli-responsive. The successful synthesis of the hydrogel was confirmed using techniques, such as proton nuclear magnetic resonance spectroscopy (1H NMR), Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). In order to compare and analyze the properties of physically crosslinked hydrogels, physically-chemically double-crosslinked hydrogels, and physically-chemically clicked triple-crosslinked hydrogels, various tests were conducted on the gels' morphology, swelling behavior, thermal stability, mechanical properties, and drug loading capacity. The results indicate that the triple-crosslinked hydrogel maintains low swelling, high mechanical strength, and good thermal stability while not significantly compromising its drug delivery capability.

A phase II open-label trial of avelumab plus axitinib in previously treated non-small-cell lung cancer or treatment-naïve, cisplatin-ineligible urothelial cancer

BACKGROUND

We hypothesized that avelumab plus axitinib could improve clinical outcomes in patients with advanced non-small-cell lung cancer (NSCLC) or urothelial carcinoma (UC).

PATIENTS AND METHODS

We enrolled previously treated patients with advanced or metastatic NSCLC, or untreated, cisplatin-ineligible patients with advanced or metastatic UC. Patients received avelumab 800 mg every 2 weeks (Q2W) and axitinib 5 mg orally two times daily. The primary endpoint was objective response rate (ORR). Immunohistochemistry was used to assess programmed death-ligand 1 (PD-L1) expression (SP263 assay) and the presence of CD8+ T cells (clone C8/144B). Tumor mutational burden (TMB) was assessed by whole-exome sequencing.

RESULTS

A total of 61 patients were enrolled and treated (NSCLC, n = 41; UC, n = 20); 5 remained on treatment at data cut-off (26 February 2021). The confirmed ORR was 31.7% in the NSCLC cohort and 10.0% in the UC cohort (all partial responses). Antitumor activity was observed irrespective of PD-L1 expression. In exploratory subgroups, ORRs were higher in patients with higher (≥median) CD8+ T cells in the tumor. ORRs were higher in patients with lower TMB (<median) in the NSCLC cohort and higher TMB (≥median) in the UC cohort. Treatment-related adverse events (TRAEs) occurred in 93.4% of patients, including grade ≥3 TRAEs in 55.7%. Avelumab exposures with 800 mg Q2W dosing were similar to those observed with 10 mg/kg Q2W dosing.

CONCLUSIONS

In previously treated patients with advanced/metastatic NSCLC, ORR appeared to be superior to anti-PD-L1 or anti-programmed cell death protein 1 monotherapy, irrespective of PD-L1 status, whereas in untreated, cisplatin-ineligible patients with advanced/metastatic UC, ORR was lower than expected, potentially limited by small patient numbers.

TRIAL REGISTRATION

Clinicaltrial.gov NCT03472560; https://clinicaltrials.gov/ct2/show/NCT03472560.

Long Non-Coding RNA and Chemoresistance in Bladder Cancer - A Mini Review

Bladder cancer is the 10th most common cancer worldwide. It is a heterogeneous disease, comprising several tumor subtypes with differences in histology, genomic aberrations, prognosis and sensitivity to anti-cancer treatments. Although the treatment of bladder cancer is based tumor classifications and gradings, patients have different clinical response. In recent years, long non-coding RNAs (lncRNAs) were associated with bladder cancer chemoresistance. Thus, lncRNAs seem to be promising targets in treatment of bladder cancer. This review highlights the recent findings concerning lncRNAs and their relevance to the chemoresistance of bladder cancer. This may provide a basis for exploiting more robust therapeutic approaches in the future.

PGM1 and ENO1 Promote the Malignant Progression of Bladder Cancer via Comprehensive Analysis of the m6A Signature and Tumor Immune Infiltration

Background

While N⁶-methyladenosine (m6A) modification of RNA and the tumor immune microenvironment both influence the progression of cancer, little attention has been paid to interactions between these two factors. Thus, we systematically explored potential biomarkers in the malignant progression of bladder urothelial carcinoma (BLCA) via combining expression of m6A methylation regulators with tumor immune infiltration.

Methods

We extracted m6A regulators from published literature, downloaded BLCA RNA-seq and clinical information from the Cancer Genome Atlas database, and integrated three main bioinformatic methods and qPCR to explore the biological variations in the malignant progression of BLCA.

Results

FTO, IGF2BP3, and YTHDC1 have a significant difference in bladder cancer and prognosis. Two subgroups (clusters 1 and 2) were identified according to three key m6A regulators; cluster 1 was preferentially associated with poor prognosis and immune infiltration relative to cluster 2 significantly. We further identified PGM1 and ENO1 as potential prognostic biomarkers, as they were correlated with FTO and IGF2BP3 positively but with YTHDC1, negatively. M2 macrophage and TFH cells were highly infiltrated in BLCA and were associated with BLCA prognosis. Finally, PGM1 and ENO1 were correlated with M2 macrophage and TFH cells and their surface markers CD163and CXCR5.

Conclusions

PGM1 and ENO1 are highly correlated with the malignant progression of BLCA, and the expression of these genes may be new indicators for the diagnosis and prognosis of BLCA.

Concise synthesis and biological activity evaluation of novel pyrazinyl–aryl urea derivatives against several cancer cell lines, which can especially induce T24 apoptotic and necroptotic cell death

Based on structural modification of regorafenib, 28 pyrazinyl–aryl urea derivatives were synthesized and the in vitro anti-cancer effects were evaluated. Compound 5-23 possessed the strongest inhibitory activity against bladder cancer T24 cell line.

GATCDA: Predicting circRNA-Disease Associations Based on Graph Attention Network

CircRNAs (circular RNAs) are a class of non-coding RNA molecules with a closed circular structure. CircRNAs are closely related to the occurrence and development of diseases. Due to the time-consuming nature of biological experiments, computational methods have become a better way to predict the interactions between circRNAs and diseases. In this study, we developed a novel computational method called GATCDA utilizing a graph attention network (GAT) to predict circRNA-disease associations with disease symptom similarity, network similarity, and information entropy similarity for both circRNAs and diseases. GAT learns representations for nodes on a graph by an attention mechanism, which assigns different weights to different nodes in a neighborhood. Considering that the circRNA-miRNA-mRNA axis plays an important role in the generation and development of diseases, circRNA-miRNA interactions and disease-mRNA interactions were adopted to construct features, in which mRNAs were related to 88% of miRNAs. As demonstrated by five-fold cross-validation, GATCDA yielded an AUC value of 0.9011. In addition, case studies showed that GATCDA can predict unknown circRNA-disease associations. In conclusion, GATCDA is a useful method for exploring associations between circRNAs and diseases.

Kinesin family member 3A stimulates cell proliferation, migration, and invasion of bladder cancer cells in vitro and in vivo

Bladder cancer is one of the most common malignant tumors of the urinary system, with high morbidity and mortality. At present, the survival rates and prognosis of patients with bladder cancer are still relatively low; thus, there remains a need to improve prognosis by identifying novel targets. Kinesins (kinesin superfamily proteins) are a series of microtubule-based motor proteins that mediate various types of cellular processes. Kinesin family member 3A (KIF3A) is critical for cytoplasm separation in mitosis, and it has been reported to be misexpressed in multiple types of cancer. However, its effects on the progression and development of bladder cancer remain unclear. Herein, we report that KIF3A is highly expressed in human bladder cancer. We identified a significant correlation between KIF3A and clinical features, including clinical stage (P = 0.047), pathological tumor status (P = 0.045), lymph node status (P = 0.041) and metastasis (P = 0.035). KIF3A expression was also correlated with poor prognosis of patients with bladder cancer. Our results further indicated that KIF3A ablation resulted in cell cycle arrest; blocked the proliferation, migration and invasion of bladder cancer cells in vitro; and restrained tumor growth in mice in a microtubule-dependent manner. In summary, our findings suggest that KIF3A is a potential therapeutic target for bladder cancer.

Impact of HER2 assessment by CISH in urothelial carcinoma: A retrospective single-center experience

BACKGROUND

In recent years, HER2 amplification has been evaluated as a potential prognostic biomarker and therapeutic target in urothelial carcinoma (UC). In this retrospective study, we aimed at exploring the prognostic role of HER2 amplification in UC, measured by chromogenic in situ hybridization (CISH).

METHODS

We retrospectively evaluated the presence of HER2 amplification by using CISH in 31 UC patients followed at a single institution between 2018 and 2020. The primary objective was to assess the frequency of HER2 amplification and to compare clinical outcomes of HER2-amplified patients with non-amplified UCs.

RESULTS

HER2 amplification was identified in 4 out of 31 patients (12.9 %). After a median follow-up of 28.1 months (95 % Confidence Intervals [CI] 11.2-45.1), median overall survival (OS) in the whole population was 10.9 months (95 % CI 3.5-22.1). Despite not reaching statistical significance, median OS was shorter in HER2-amplified patients (6.8 months, 95 % CI 3.9-9.7) compared to HER2-negative UCs (15.4 months, 95 % CI 7.5-23.3) (p = 0.45).

CONCLUSIONS

Although limited by the small sample size, the results of our study suggest that HER2 amplifications by CISH could represent a prognostic factor for shorter survival in UC patients.

Comparative bioinformatics analysis of prognostic and differentially expressed genes in non-muscle and muscle invasive bladder cancer

Bladder cancer (BC) is classified into non-muscle (NMIBC) and muscle invasive (MIBC) diseases. Several molecular alterations were previously associated with NMIBC and MIBC, but few studies have systematically compared the molecular differences between these subtypes. Here, we analyzed prognostic and differentially expressed genes in NMIBC and MIBC, using an integrative bioinformatics approach. These genes were used in functional enrichment and co-expression protein interaction (COPI) network analyses to reveal common and exclusive biological functions involved in NMIBC and MIBC. In NMIBC, the enriched functions were related to oxidative stress response, cell cycle, glutathione metabolism, ubiquitination and protein translation. Conversely, enriched functions in MIBC were extracellular matrix organization, cell migration and actin cytoskeleton. Several genes in NMIBC did not overlap with those reported to MIBC, suggesting these subtypes may have distinct underlying mechanisms. Particularly, MIBC genes were enriched for functions involved in cell migration and invasion, which could help to molecularly differentiate NMIBC and MIBC. The analysis of COPI networks disclosed high centrality nodes that may be essential for NMIBC and MIBC. Further research will determine to which extent NMIBC and MIBC share common biological functions and identify potential candidates for the differential diagnosis, prognosis and treatment of NMIBC and MIBC. SIGNIFICANCE: This study has systematically compared prognostic and differentially expressed genes between non-muscle (NMIBC) and muscle invasive (MIBC) bladder cancer, using an integrative bioinformatics approach. Many genes and biological functions were exclusively associated with either NMIBC or MIBC, suggesting that these disease subtypes could be driven by distinct molecular mechanisms. Particularly, prognostic and differentially expressed genes in MIBC were involved in cell migration and invasion, which can help to molecularly differentiate the NMIBC and MIBC subtypes. Moreover, the analysis of co-expression protein interaction networks identified high centrality nodes that could be potential candidates for the prognosis and treatment of NMIBC and MIBC.

microRNA-451a promoter methylation regulated by DNMT3B expedites bladder cancer development via the EPHA2/PI3K/AKT axis

BACKGROUND

The downregulation of microRNA (miR)-451a has been reported in bladder cancer (BCa) tissues. Herein, we elucidated the role of miR-451a in BCa with the involvement of DNA methyltransferase 3B (DNMT3B).

METHODS

We first screened the differentially expressed miRNAs from the serum of 12 BCa patients and 10 healthy controls in the BCa database GSE113486. Subsequently, we detected miR-451a expression and CpG island methylation of the promoter in BCa cells T24 and 5637 with DNMT3B knockdown. The downstream mRNAs of miR-451a were predicted by bioinformatics and KEGG enrichment analysis. Afterwards, the expression patterns of DNMT3B, miR-451a and erythropoietin-producing hepatocellular receptor tyrosine kinase class A2 (EPHA2) were altered in BCa cells to test the ability of cell proliferation, apoptosis, migration as well as invasion. Finally, the effect of miR-451a and DNMT3B was evaluated in vivo.

RESULTS

miR-451a was significantly reduced in serum of BCa patients and cell lines. Moreover, the expression of DNMT3B in BCa cells was significantly increased, thus promoting methylation of the miR-451a promoter, resulting in miR-451a inhibition. Additionally, we found that miR-451a targeted and negatively regulated EPHA2, while EPHA2 could activate the PI3K/AKT signaling, driving BCa cell growth and metastasis.

CONCLUSIONS

Our study proposed and demonstrated that miR-451a downregulation mediated by DNMT3B is critical for proliferation, migration, and invasion of BCa, which may be beneficial for developing more effective therapies against BCa.

The therapeutic and prognostic implications of molecular biomarkers in urothelial carcinoma

Urothelial cell carcinoma (UCC) of the bladder and upper urinary tract is a heterogeneous disease with distinct biologic features resulting in different clinical behaviors. Bladder cancer (BC) is classified into non-muscle invasive BC (NMIBC) and muscle invasive BC (MIBC). NMIBC is associated with high recurrence rates and risk of progression to invasive disease, whereas MIBC is complicated by systemic recurrence after radical cystectomy because of the limited efficacy of available therapies. UCC of the upper urinary tract (UUT-UCC) is a rare but aggressive urologic cancer characterized by multifocality, local recurrence, and metastasis. Conventional histopathologic evaluation of UCC, including tumor stage and grade, cannot accurately predict the behavior of BC and UUT-UCC. Recent clinical and preclinical studies aimed at understanding the molecular landscape of UCC have provided insight into molecular subtyping, inter- or intratumoral heterogeneity, and potential therapeutic targets. Combined analysis of molecular markers and standard pathological features may improve risk stratification and help monitor tumor progression and treatment response, ultimately improving patient outcomes. This review discusses prognostic and therapeutic biomarkers for BC and UUT-UCC, and describes recent advances in molecular stratification that may guide prognosis, patient stratification, and treatment selection.

Screening and Identifying Immune-Related Cells and Genes in the Tumor Microenvironment of Bladder Urothelial Carcinoma: Based on TCGA Database and Bioinformatics

Bladder cancer is the most common cancer of the urinary system and its treatment has scarcely progressed for nearly 30 years. Advances in checkpoint inhibitor research have seemingly provided a new approach for treatment. However, there have been issues predicting immunotherapeutic biomarkers and identifying new therapeutic targets. We downloaded the gene expression profile and clinical data of 408 cases bladder urinary cancer from the Cancer Genome Atlas (TCGA) portal, and the abundance ratio of immune cells for each sample was obtained via the "Cell Type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT)" algorithm. Then, four survival-related immune cells were obtained via Kaplan-Meier survival analysis, and 933 immune-related genes were obtained via a variance analysis. Enrichment, protein-protein interaction, and co-expression analyses were performed for these genes. Lastly, 4 survival-related immune cells and 24 hub genes were identified, four of which were related to overall survival. More importantly, these immune cells and genes were closely related to the clinical features. These cells and genes may have research value and clinical application in bladder cancer immunotherapy. Our study not only provides cell and gene targets for bladder cancer immunotherapy, but also provides new ideas for researchers to explore the immunotherapy of various tumors.