Genetic determinants for chemo- and radiotherapy resistance in bladder cancer

Progress on liposome delivery systems in the treatment of bladder cancer

Bladder cancer (BC) in the urinary system remains one of the most prevalent malignancies with high recurrence rate globally. Current treatment schemes against BC such as surgery, chemotherapy, and radiotherapy have substantial limitations including side effects, drug resistance, and poor tumor targeting. Considering the above-mentioned challenges, nanotechnology has become a current research hotspot, particularly liposome-based drug delivery systems, which offer promising novel therapeutic strategies aimed at reducing systemic toxicity, overcoming drug resistance, and enhancing drug targeting. This review systematically elaborates the current research progress on liposomal drug delivery systems in BC treatment, focusing on their application in chemotherapy, immunotherapy, and gene therapy. Additionally, we provide a comprehensive assessment of the benefits and limitations of liposome nanocarriers used in BC treatment. The advanced targeting strategies and combination treatments via liposomal therapies are also discussed, demonstrating that liposomal formulations have great potential application value in the treatment of BC owing to their superior bioavailability, stability, and targeting and minimal adverse effects.

Hyperthermia reduces cancer cell invasion and combats chemoresistance and immune evasion in human bladder cancer

Bladder cancer (BC) is a common malignancy and its most prevalent type is urothelial carcinoma, which accounts for ~90% of all cases of BC. The current treatment options for BC are limited, which necessitates the development of alternative treatment strategies. Hyperthermia (HT), as an adjuvant cancer therapy, is known to improve the efficacy of chemotherapy or radiotherapy. The present study aimed to investigate the anti‑tumor effects of HT on cell survival, invasiveness, chemoresistance and immune evasion in human BC cell lines (5637, T24 and UMUC3). Calcein AM staining was performed to analyze the cytotoxicity of natural killer (NK) cells against human BC cells following HT treatment. Cell migration and invasion affected by HT were analyzed using Transwell migration and invasion assays. It was found that HT inhibited the proliferation of BC cells by downregulating the phosphorylation of protein kinase B. Moreover, HT effectively enhanced the sensitivity of BC cells to the chemotherapy drug cisplatin (DDP) and reduced the chemoresistance of DDP‑resistant cells by downregulating the expression of cadherin‑11. It was further demonstrated that HT inhibited the migration and invasion of BC cells and enhanced the cytotoxic effects of NK cells. In summary, the antineoplastic effects of HT were mediated through three main mechanisms: Enhancement of the chemosensitivity of BC cells and mitigation of DDP‑induced chemoresistance, suppression of the invasive potential of BC cells and reinforcement of the anticancer response of NK cells. Thus, HT appears to be a promising adjunctive therapy for human BC.

Relationship between ERCC1 and XPC polymorphisms and the susceptibility to head and neck carcinoma: A systematic review, meta-analysis, and trial sequential analysis

OBJECTIVE

This meta-analysis was conducted to investigate the relationship between ERCC1 and XPC polymorphisms and the risk of head and neck cancer (HNC), incorporating more studies and additional analyses.

DESIGN

An exhaustive search of various databases, including PubMed/Medline, Web of Science, Scopus, and Cochrane Library was carried out, up until November 18, 2023, to identify pertinent studies. The Review Manager 5.3 software was employed to calculate the effect sizes, which were presented as the odds ratio (OR) along with a 95% confidence interval (CI).

RESULTS

The study found that the T allele (OR = 1.11; p-value = 0.02; 95%CI: 1.02, 1.22) and the TT genotype rs2228000 polymorphism in both the homozygous model (OR = 1.61, p-value = 0.02; 95%CI: 1.07, 2.42) and the recessive model (OR = 1.53; p-value = 0.02; 95%CI: 1.06, 2.22) had statistically significant associations. However, no significant associations were found for rs11615, rs3212986, rs735482, rs2228001, and PAT polymorphisms in any genetic models.

CONCLUSIONS

The meta-analysis revealed significant associations for the T allele and TT genotype rs2228000 polymorphism, but not for rs11615, rs3212986, rs735482, rs2228001, and PAT polymorphisms. The results highlight the impact of factors such as ethnicity, cancer subtype, and control source on these associations, emphasizing the intricate nature of genetic interactions in disease risk.

Bioinformatics analysis and experimental validation reveal that CDC20 overexpression promotes bladder cancer progression and potential underlying mechanisms

BACKGROUND

Bladder cancer is a prevalent malignancy. CDC20, a pivotal cell cycle regulator gene, plays a significant role in tumour cell proliferation, but its role in bladder cancer remains unclear.

OBJECTIVE

This study aimed to analyse CDC20 expression in bladder cancer and explore its roles in tumour progression, treatment response, patient prognosis, and cellular proliferation mechanisms.

METHODS

We systematically analysed CDC20 expression in bladder cancer using bioinformatics. Our study investigated the impact of CDC20 on chemotherapy and radiotherapy sensitivity, patient prognosis, and changes in CDC20 methylation levels. We also explored the role and potential underlying mechanisms of CDC20 in bladder cancer cell growth. We used lentiviral transfection to downregulate CDC20 expression in 5637 and T24 cells, followed by CCK-8, colony formation, scratch, invasion, apoptosis, and cell cycle analyses.

RESULTS

CDC20 is highly expressed in bladder cancer and is significantly correlated with poor prognosis. Moreover, CDC20 demonstrated high diagnostic potential for bladder cancer (AUC > 0.9). The tumour methylation levels of CDC20 in tumour tissues markedly decreased compared with those in normal tissues, and lower methylation levels were associated with a worse prognosis. Elevated CDC20 expression is linked to increased mutation burden. Our findings suggested a potential association between high CDC20 expression and resistance to chemotherapy and radiotherapy, as CDC20 expression may impact immune cell infiltration levels. Mechanistic analysis revealed the influence of CDC20 on bladder cancer cell proliferation through cell cycle-related pathways. According to the cell experiments, CDC20 downregulation significantly impedes bladder cancer cell proliferation and invasion, leading to G1 phase arrest.

CONCLUSION

Aberrantly high CDC20 expression promotes tumour progression in bladder cancer, resulting in a poor prognosis, and may also constitute a promising therapeutic target.

Phase II trial of afatinib in patients with advanced urothelial carcinoma with genetic alterations in ERBB1-3 (LUX-Bladder 1)

BACKGROUND

Preclinical and early clinical data suggest that the irreversible ErbB family blocker afatinib may be effective in urothelial cancers harbouring ERBB mutations.

METHODS

This open-label, phase II, single-arm trial (LUX-Bladder 1, NCT02780687) assessed the efficacy and safety of second-line afatinib 40 mg/d in patients with metastatic urothelial carcinoma with ERBB1-3 alterations. The primary endpoint was 6-month progression-free survival rate (PFS6) (cohort A); other endpoints included ORR, PFS, OS, DCR and safety (cohorts A and B). Cohort A was planned to have two stages: stage 2 enrolment was based on observed antitumour activity.

RESULTS

Thirty-four patients were enroled into cohort A and eight into cohort B. In cohorts A/B, PFS6 was 11.8%/12.5%, ORR was 5.9%/12.5%, DCR was 50.0%/25.0%, median PFS was 9.8/7.8 weeks and median OS was 30.1/29.6 weeks. Three patients (two ERBB2-amplified [cohort A]; one EGFR-amplified [cohort B]) achieved partial responses. Stage 2 for cohort A did not proceed. All patients experienced adverse events (AEs), most commonly (any/grade 3) diarrhoea (76.2%/9.5%). Two patients (4.8%) discontinued due to AEs and one fatal AE was observed (acute coronary syndrome; not considered treatment-related).

CONCLUSIONS

An exploratory biomarker analysis suggested that basal-squamous tumours and ERBB2 amplification were associated with superior response to afatinib.

CLINICAL TRIAL REGISTRATION

NCT02780687.

Multi-omics reveals the role of ENO1 in bladder cancer and constructs an epithelial-related prognostic model to predict prognosis and efficacy

α-Enolase (ENO1) is a crucial molecular target for tumor therapy and has emerged as a research hotspot in recent decades. Here, we aimed to explore the role of ENO1 in bladder cancer (BLCA) and then construct a signature to predict the prognosis and treatment response of BLCA. Firstly, we found ENO1 was highly expressed in BLCA tissues, as verified by IHC, and was associated with poor prognosis. The analysis of the tumor immune microenvironment by bulk RNA-seq and scRNA-seq showed that ENO1 was associated with CD8+ T-cell exhaustion. Additionally, the results in vitro showed that ENO1 could promote the proliferation and invasion of BLCA cells. Then, the analysis of epithelial cells (ECs) revealed that ENO1 might promote BLCA progression by metabolism, the cell cycle and some carcinogenic pathways. A total of 249 hub genes were obtained from differentially expressed genes between ENO1-related ECs, and we used LASSO analysis to construct a novel signature that not only accurately predicted the prognosis of BLCA patients but also predicted the response to treatment for BLCA. Finally, we constructed a nomogram to better guide clinical application. In conclusion, through multi-omics analysis, we found that ENO1 was overexpressed in bladder cancer and associated with poor prognosis, CD8+ T-cell exhaustion and epithelial heterogeneity. Moreover, the prognosis and treatment of patients can be well predicted by constructing an epithelial-related prognostic signature.

Metabolic reprogramming based on RNA sequencing of gemcitabine-resistant cells reveals the FASN gene as a therapeutic for bladder cancer

Bladder cancer (BLCA) is the most frequent malignant tumor of the genitourinary system. Postoperative chemotherapy drug perfusion and chemotherapy are important means for the treatment of BLCA. However, once drug resistance occurs, BLCA develops rapidly after recurrence. BLCA cells rely on unique metabolic rewriting to maintain their growth and proliferation. However, the relationship between the metabolic pattern changes and drug resistance in BLCA is unclear. At present, this problem lacks systematic research. In our research, we identified and analyzed resistance- and metabolism-related differentially expressed genes (RM-DEGs) based on RNA sequencing of a gemcitabine-resistant BLCA cell line and metabolic-related genes (MRGs). Then, we established a drug resistance- and metabolism-related model (RM-RM) through regression analysis to predict the overall survival of BLCA. We also confirmed that RM-RM had a significant correlation with tumor metabolism, gene mutations, tumor microenvironment, and adverse drug reactions. Patients with a high drug resistance- and metabolism-related risk score (RM-RS) showed more active lipid synthesis than those with a low RM-RS. Further in vitro and in vivo studies were implemented using Fatty Acid Synthase (FASN), a representative gene, which promotes gemcitabine resistance, and its inhibitor (TVB-3166) that can reverse this resistance effect.

Bladder cancer: therapeutic challenges and role of 3D cell culture systems in the screening of novel cancer therapeutics

Bladder cancer (BC) is the sixth most common worldwide urologic malignancy associated with elevated morbidity and mortality rates if not well treated. The muscle-invasive form of BC develops in about 25% of patients. Moreover, according to estimates, 50% of patients with invasive BC experience fatal metastatic relapses. Currently, resistance to drug-based therapy is the major tumble to BC treatment. The three-dimensional (3D) cell cultures are clearly more relevant not only as a novel evolving gadget in drug screening but also as a bearable therapeutic for different diseases. In this review, various subtypes of BC and mechanisms of drug resistance to the commonly used anticancer therapies are discussed. We also summarize the key lineaments of the latest cell-based assays utilizing 3D cell culture systems and their impact on understanding the pathophysiology of BC. Such knowledge could ultimately help to address the most efficient BC treatment.

The G protein-coupled receptor-related gene signatures for predicting prognosis and immunotherapy response in bladder urothelial carcinoma

Bladder urothelial carcinoma (BLCA) is the most common malignant tumor of the urinary tract with a high lethality rate, and its immunotherapy resistance and tumor recurrence have become a major challenge in its clinical treatment. G Protein-Coupled Receptors (GPRs) are the largest family of receptors on the cell membrane surface, involved in multiple signaling pathways, and are excellent targets for oncology drug action. The transcriptome profile, single cell transcriptome profile, and clinical data of BLCA were extracted and integrated from TCGA and GEO databases, respectively. The GPR-related genes were obtained from GSEA-MSigDB database. The GPR-related gene signatures of 15 genes were constructed by using the methods of least absolute shrinkage and selection operator regression, multifactor Cox model. At the same time, tumor microenvironment (TME)-score signatures were constructed based on the immune microenvironment of BLCA, and GPR-TME-score signature was further constructed. The stability of this model was verified by using the external dataset GSE160693. We constructed risk groups by combining BLCA patient prognostic information, and with the help of BLCA scRNA transcriptome profiling, we explored differences in prognosis, immune scores, cell-cell interactions, tumor mutational burden, immune checkpoints, and response to immunotherapy in each risk group. We found that the GPR-TME-score signature was an independent prognostic factor for BLCA patients. the TME-score was a protective factor for the prognosis of BLCA patients. Among BLCA patients, GPR-high + TME-low risk group had the worst prognosis, while GPR-high + TME-high risk group had the best prognosis, and the latter had better immune score and immunotherapy response. The above differences in immune response among the subgroups may be related to the higher immune cell infiltration in the GPR-high + TME-high group. GPR-related gene signatures and TME are closely related to BLCA prognosis and immunotherapy, and GPR-related gene signature can be a useful tool to assess BLCA prognosis and immunotherapy response.

Brazilin inhibits bladder cancer by promoting cell necroptosis

Brazilin possesses anticancer effects, but the mechanisms are poorly understood. This study investigated the mechanisms of brazilin-induced cell death in the T24 human bladder cancer cell line. Low serum cell culture and the lactate dehydrogenase assay were used to confirm the antitumor effect of brazilin. Annexin V and propidium iodide double staining, transmission electron microscopy, fluo-3-AM assay for Ca²⁺ mobilization and caspase activity assay were performed to identify the type of cell death after brazilin treatment. Mitochondria membrane potentials were measured using JC-1. Quantitative real-time polymerase chain reaction and western blot analyses were performed to verify the expression of the necroptosis-related genes and proteins receptor interacting protein 1 (RIP1), RIP3 and mixed lineage kinase domain-like (MLKL). The results showed that brazilin induced necrosis in T24 cells and upregulated the mRNA and protein levels of RIP1, RIP3 and MLKL and Ca²⁺ influx. The necroptosis-mediated cell death was rescued by the necroptosis inhibitor necrostatin-1 (Nec-1), but not by the apoptosis inhibitor z-VAD-fmk. Brazilin repressed caspase 8 expression and decreased the mitochondrial membrane potentials; both effects were partially reversed by Nec-1. Brazilin induced physiological and morphological changes in T24 cells and RIP1/RIP3/MLKL-mediated necroptosis might be involved. In conclusion, the results confirm the involvement of necroptosis in brazilin-induced cell death and suggest that brazilin could be explored as an anticancer agent against bladder cancer.

Assessing the Performance of 18F-FDG PET/CT in Bladder Cancer: A Narrative Review of Current Evidence

INTRODUCTION

Lymph node (LN) involvement is a crucial determinant of prognosis for patients with bladder cancer, and an accurate staging is of utmost importance to better identify timely and appropriate therapeutic strategies. To improve the accuracy of LN detection, as an alternative to traditional methods such as CT or MRI, 18F-FDG PET/CT has been increasingly used. 18F-FDG PET/CT is also used in post-treatment restaging after neoadjuvant chemotherapy. The aim of this narrative literature review is to provide an overview of the current evidence on the use of 18F-FDG PET/CT in the diagnosis, staging, and restaging of bladder cancer, with a particular focus on its sensitivity and specificity for the detection of LN metastasis. We aim to provide clinicians with a better understanding of 18F-FDG PET/CT's potential benefits and limitations in clinical practice.

MATERIALS AND METHODS

We designed a narrative review starting from a wide search in the PubMed/MEDLINE and Embase databases, selecting full-text English articles that have examined the sensibility and specificity of PET/CT for nodal staging or restaging after neoadjuvant therapy in patients with bladder cancer. The extracted data were analyzed and synthesized using a narrative synthesis approach. The results are presented in a tabular format, with a summary of the main findings of each study.

RESULTS

Twenty-three studies met the inclusion criteria: fourteen studies evaluated 18F-FDG PET/CT for nodal staging, six studies examined its accuracy for restaging after neoadjuvant therapy, and three studies evaluated both applications. To date, the use of F-18 FDG PET/TC for detection of LN metastasis in bladder cancer is controversial and uncertain: some studies showed low accuracy rates, but over the years other studies have reported evidence of high sensitivity and specificity.

CONCLUSIONS

18F-FDG PET/CT provides important incremental staging and restaging information that can potentially influence clinical management in MIBC patients. Standardization and development of a scoring system are necessary for its wider adoption. Well-designed randomized controlled trials in larger populations are necessary to provide consistent recommendations and consolidate the role of 18F-FDG PET/CT in the management of bladder cancer patients.

Non-coding RNAs in radiotherapy resistance: Roles and therapeutic implications in gastrointestinal cancer

Radiotherapy has become an indispensable and conventional means for patients with advanced solid tumors including gastrointestinal cancer. However, innate or acquired radiotherapy resistance remains a significant challenge and greatly limits the therapeutic effect, which results in cancer relapse and poor prognosis. Therefore, it is an urgent need to identify novel biomarkers and therapeutic targets for clarify the biological characteristics and mechanism of radiotherapy resistance. Recently, lots of studies have revealed that non-coding RNAs (ncRNAs) are the potential indicators and regulators of radiotherapy resistance via the mediation of various targets/pathways in different cancers. These findings may serve as a potential therapeutic strategy to overcome radiotherapy resistance. In this review, we will shed light on the recent findings regarding the functions and regulatory mechanisms of ncRNAs following radiotherapy, and comprehensively discuss their potential as biomarkers and therapeutic targets in radiotherapy resistance of gastrointestinal cancer.

(Nano)platforms in bladder cancer therapy: Challenges and opportunities

Urological cancers are among the most common malignancies around the world. In particular, bladder cancer severely threatens human health due to its aggressive and heterogeneous nature. Various therapeutic modalities have been considered for the treatment of bladder cancer although its prognosis remains unfavorable. It is perceived that treatment of bladder cancer depends on an interdisciplinary approach combining biology and engineering. The nanotechnological approaches have been introduced in the treatment of various cancers, especially bladder cancer. The current review aims to emphasize and highlight possible applications of nanomedicine in eradication of bladder tumor. Nanoparticles can improve efficacy of drugs in bladder cancer therapy through elevating their bioavailability. The potential of genetic tools such as siRNA and miRNA in gene expression regulation can be boosted using nanostructures by facilitating their internalization and accumulation at tumor sites and cells. Nanoparticles can provide photodynamic and photothermal therapy for ROS overgeneration and hyperthermia, respectively, in the suppression of bladder cancer. Furthermore, remodeling of tumor microenvironment and infiltration of immune cells for the purpose of immunotherapy are achieved through cargo-loaded nanocarriers. Nanocarriers are mainly internalized in bladder tumor cells by endocytosis, and proper design of smart nanoparticles such as pH-, redox-, and light-responsive nanocarriers is of importance for targeted tumor therapy. Bladder cancer biomarkers can be detected using nanoparticles for timely diagnosis of patients. Based on their accumulation at the tumor site, they can be employed for tumor imaging. The clinical translation and challenges are also covered in current review.

Radical cystectomy in non-metastatic sarcomatoid bladder cancer: A direct comparison vs urothelial bladder cancer

INTRODUCTION

The effect of radical cystectomy (RC) on cancer-specific mortality (CSM) is unclear in non-metastatic sarcomatoid bladder cancer (SBC) patients. We aimed to test the benefit of RC in SBC, and to perform a direct comparison vs urothelial bladder cancer (UCB).

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results database (SEER 2001-2018) all non-metastatic SBC and UBC patients were identified. Endpoint of interest was CSM. Propensity score matching (PSM), cumulative incidence plots, competing risks regression (CRR) analyses, three-months landmark analyses, and sensitivity analyses were performed. All results were stratified according to organ-confined (OC: T₂N₀M₀) vs non-organ-confined (NOC: T_3-4N₀M₀ or T_anyN_1-3M₀) stages.

RESULTS

Of 554 SBC patients, 49 vs 51% harbored OC vs NOC stages. Of 47,741 UBC patients, 62 vs 38% harbored OC vs NOC stages. RC rates were 33 vs 67% in OC vs NOC-SBC patients, and 40 vs 60% in OC vs NOC-UBC patients. After 1:1 PSM, comparison between RC vs no-RC was performed in OC-SBC (67 patients per group), OC-UBC (7611 patients per group), NOC-SBC (63 patients per group), and NOC-UBC patients (4644 patients per group). CRR hazard ratios associated with RC vs no-RC were 0.37 (p < 0.001) in OC-SBC vs 0.45 (p < 0.001) in OC-UBC, and 0.56 (p = 0.01) in NOC-SBC vs 0.68 (p < 0.001) in NOC-UBC. These results were replicated in sensitivity and landmark analyses.

CONCLUSIONS

The protective effect of RC vs no-RC is stronger in SBC than UBC patients, regardless of OC vs NOC stages.

Non-invasive medical gas plasma augments bladder cancer cell toxicity in preclinical models and patient-derived tumor tissues

INTRODUCTION

Medical gas plasma therapy has been successfully applied to several types of cancer in preclinical models. First palliative tumor patients suffering from advanced head and neck cancer benefited from this novel therapeutic modality. The gas plasma-induced biological effects of reactive oxygen and nitrogen species (ROS/RNS) generated in the plasma gas phase result in oxidation-induced lethal damage to tumor cells.

OBJECTIVES

This study aimed to verify these anti-tumor effects of gas plasma exposure on urinary bladder cancer.

METHODS

2D cell culture models, 3D tumor spheroids, 3D vascularized tumors grown on the chicken chorion-allantois-membrane (CAM) in ovo, and patient-derived primary cancer tissue gas plasma-treated ex vivo were used.

RESULTS

Gas plasma treatment led to oxidation, growth retardation, motility inhibition, and cell death in 2D and 3D tumor models. A marked decline in tumor growth was also observed in the tumors grown in ovo. In addition, results of gas plasma treatment on primary urothelial carcinoma tissues ex vivo highlighted the selective tumor-toxic effects as non-malignant tissue exposed to gas plasma was less affected. Whole-transcriptome gene expression analysis revealed downregulation of tumor-promoting fibroblast growth factor receptor 3 (FGFR3) accompanied by upregulation of apoptosis-inducing factor 2 (AIFm2), which plays a central role in caspase-independent cell death signaling.

CONCLUSION

Gas plasma treatment induced cytotoxicity in patient-derived cancer tissue and slowed tumor growth in an organoid model of urinary bladder carcinoma, along with less severe effects in non-malignant tissues. Studies on the potential clinical benefits of this local and safe ROS therapy are awaited.

Identification and validation of an immune signature associated with EMT and metabolic reprogramming for predicting prognosis and drug response in bladder cancer

Background

Epithelial-mesenchymal transition (EMT), one leading reason of the dismal prognosis of bladder cancer (BLCA), is closely associated with tumor invasion and metastasis. We aimed to develop a novel immune−related gene signature based on different EMT and metabolic status to predict the prognosis of BLCA.

Methods

Gene expression and clinical data were obtained from TCGA and GEO databases. Patients were clustered based on EMT and metabolism scores calculated by ssGSEA. The immune-related differentially expressed genes (DEGs) between the two clusters with the most obvious differences were used to construct the signature by LASSO and Cox analysis. Time-dependent receiver operating characteristic (ROC) curves and Kaplan–Meier curves were utilized to evaluate the gene signature in training and validation cohorts. Finally, the function of the signature genes AHNAK and NFATC1 in BLCA cell lines were explored by cytological experiments.

Results

Based on the results of ssGSEA, TCGA patients were divided into three clusters, among which cluster 1 and cluster 3 had completely opposite EMT and metabolic status. Patients in cluster 3 had a significantly worse clinical prognosis than cluster 1. Immune-related DEGs were selected between the two clusters to construct the predictive signature based on 14 genes. High-risk patients had poorer prognosis, lower proportions of CD8⁺ T cells, higher EMT and carbohydrate metabolism, and less sensitivity to chemotherapy and immunotherapy. Overexpression of AHNAK or NFATC1 promoted the proliferation, migration and invasion of T24 and UMUC3 cells. Silencing ANHAK or NFATC1 could effectively inhibit EMT and metabolism in T24 and UMUC3 cells.

Conclusion

The established immune signature may act as a promising model for generating accurate prognosis for patients and predicting their EMT and metabolic status, thus guiding the treatment of BLCA patients.

Norcantharidin Induces Immunogenic Cell Death of Bladder Cancer Cells through Promoting Autophagy in Acidic Culture

The acidic tumor microenvironment stands as a major obstacle to the efficient elimination of tumor cells. Norcantharidin (NCTD) is a powerful antitumor agent with multiple bioactivities. However, the effect of NCTD under acidic conditions is still unclear. Here, we report that NCTD can efficiently kill bladder cancer (BC) cells in acidic culture, and more intriguingly, NCTD can induce immunogenic cell death (ICD), thereby promoting antitumor immunity. In NCTD-treated BC cells, the surface-exposed calreticulin (ecto-CALR) was significantly increased. Consistently, co-culture with these cells promoted dendritic cell (DC) maturation. The NCTD-induced ICD is autophagy dependent, as autophagy inhibition completely blocked the NCTD-induced ecto-CALR and DC maturation. In addition, the DC showed a distinct maturation phenotype (CD80^high CD86^low) in acidic culture, as compared to that in physiological pH (CD⁸⁰ high CD86^high). Finally, the NCTD-induced ICD was validated in a mouse model. NCTD treatment significantly increased the tumor-infiltrating T lymphocytes in MB49 bladder cancer mice. Immunizing mice with NCTD-treated MB49 cells significantly increased tumor-free survival as compared to control. These findings demonstrate that NCTD could induce ICD in an acidic environment and suggest the feasibility to combine NCTD with anticancer immunotherapy to treat BC.

AKT1 and PIK3CA activating mutations in Moroccan bladder cancer patients´ biopsies and matched urine

Introduction

in cancer cells, activating mutations in PIK3CA and AKT1 genes, major players of PI3K-AKT-mTOR signalling pathway, are widely reported in many cancers and present attractive targets for the identification of new therapeutics and better cancer management. The present study was planned to evaluate the mutational status of PIK3CA and AKT1 genes in bladder cancer patients and to assess the association between these mutations and patients´ clinico-pathological features.

Methods

in this prospective study, bladder cancer biopsies and matched urine sediments samples were collected form 70 patients. Mutations were assessed by deoxyribonucleic acid (DNA) sequencing and correlation with clinico-pathological data was performed using SPSS software.

Results

AKT1 alterations were poorly detected. Only one patient with pT1 stage and high-grade tumour carried the E17K mutation. In PIK3CA exon 9, 2 point mutations, E545K and Q546E, and a SNP (E547E) were reported, whereas in exon 20, 2 point mutations (L989V and H1047R) and 2 SNPs (I1022I and T1025T) were detected. PIK3CA mutations were mainly observed in early stages and high-grade tumours. Statistical analysis showed no significant association between the studied AKT1 and PIK3CA mutations and patients´ clinico-pathological parameters (p > 0.05). Detection of these mutations in voided urine samples showed a high specificity (100%) for both genes and a moderate sensitivity: 100% for AKT1 and 66.7% for PIK3CA genes.

Conclusion

this study shows clearly that mutations in AKT1 and PIK3CA are rare events and could not be considered as valuable biomarkers for bladder cancer management.

Nobiletin as an inducer of programmed cell death in cancer: a review

Cancer resistance to therapy is a big issue in cancer therapy. Tumours may develop some mechanisms to reduce the induction of cell death, thus stimulating tumour growth. Cancer cells may show a low expression and activity of tumour suppressor genes and a low response to anti-tumour immunity. These mutations can increase the resistance of cancer cells to programmed cell death mechanisms such as apoptosis, ferroptosis, pyroptosis, autophagic cell death, and some others. The upregulation of some mediators and transcription factors such as Akt, nuclear factor of κB, signal transducer and activator of transcription 3, Bcl-2, and others can inhibit cell death in cancer cells. Using adjuvants to induce the killing of cancer cells is an interesting strategy in cancer therapy. Nobiletin (NOB) is a herbal-derived agent with fascinating anti-cancer properties. It has been shown to induce the generation of endogenous ROS by cancer cells, leading to damage to critical macromolecules and finally cell death. NOB may induce the activity of p53 and pro-apoptosis mediators, and also inhibit the expression and nuclear translocation of anti-apoptosis mediators. In addition, NOB may induce cancer cell killing by modulating other mechanisms that are involved in programmed cell death mechanisms. This review aims to discuss the cellular and molecular mechanisms of the programmed cell death in cancer by NOB via modulating different types of cell death in cancer.

The Prognostic Role of CDK9 in Bladder Cancer

Introduction: Most patients with urothelial carcinoma are diagnosed with non-invasive tumors, but the prognosis worsens with the progression of the disease. Overexpression of cyclin-dependent kinase 9 has been recently linked to increased cancer proliferation, faster progression, and worse prognosis. However, some cancers seem to contradict this rule. In this work, we explored the prognostic role of CDK9 expression in urothelial carcinoma. Materials and Methods: We performed immunohistochemical analysis on 72 bladder cancer samples. To assess a larger group of patients, the Cancer Genome Atlas (TCGA) database containing 406 cases and transcriptomics information through the Human Pathology Atlas were analyzed. Results: CDK9 is overexpressed in urothelial cancer tissues when compared to normal urothelial tissues (p < 0.05). High CDK9 expression was observed in low-stage, low-grade, and non-muscle-invasive tumors (p < 0.05). The patients with high CDK9 expression had a significantly higher 5-year overall survival rate than those with low CDK9 expression (77.54% vs. 53.6% in the TMA group and 57.75% vs. 35.44% in the TCGA group, respectively) (p < 0.05). The results were consistent in both cohorts. Multivariate Cox regression analysis indicated that low CDK9 status was an independent predictor for poor prognosis in the TCGA cohort (HR 1.60, CL95% 1.1−2.33, p = 0.014). Conclusions: High CDK9 expression predicts a favorable prognosis in urothelial carcinoma and is associated with clinicopathological features characteristic for early-stage disease. The decrease in CDK9 expression can be associated with the build-up of genetic instability and may indicate a key role for CDK9 in the early stages of urothelial carcinoma.

High expression of tight junction protein 1 as a predictive biomarker for bladder cancer grade and staging

Tight junction proteins 1-3 (TJP1-3) are components of tight junctions that can link transmembrane proteins to the actin cytoskeleton, and their incidence directly correlates to metastasis. However, the role of the TJP family in bladder cancer has not been adequately evaluated. In this study, we evaluated the genetic changes, mRNA and protein expressions of the target genes of the TJP family in bladder cancer patients using online database and immunohistochemistry, respectively. We found that TJP1 was amplified in bladder cancer tissue and that the protein expression levels were significantly associated with age (p = 0.03), grade (p = 0.007), and stage (p = 0.011). We also examined the correlation between TJP1 and other high-frequency mutation genes using TIMER. TJP1 mRNA levels were positively correlated with TTN and RYR3 mRNA levels in bladder cancer tissue. Taken together, TJP1 expression is associated with poor clinical outcomes in patients with bladder cancer and can be a useful predictive biomarker for bladder cancer staging.

Curcumin May Prevent Basement Membrane Disassembly by Matrix Metalloproteinases and Progression of the Bladder Cancer

Authors present a review of crucial mechanisms contributing to the invasion of the basement membrane (BM) of the urothelium by cancer cells and to the progression of bladder cancer (BC). The breeching of the urothelial BM, facilitated by an aberrant activation of matrix metalloproteinases (MMP) is particularly perilous. Inhibition of activation of these proteinases constitutes a logic opportunity to restrain progression. Because of limited efficacy of current therapeutic methods, the search for the development of alternative approaches constitutes "the hot spot" of modern oncology. Recent studies revealed significant anticancer potential of natural phytochemicals. Especially, curcumin has emerged as a one of the most promising phytochemicals and showed its efficacy in several human malignancies. Therefore, this article addresses experimental and clinical data indicating multi-directional inhibitory effect of curcumin on the growth of bladder cancer. We particularly concentrate on the mechanisms, by which curcumin inhibits the MMP's activities, thereby securing BM integrity and alleviating the eventual cancer invasion into the bladder muscles. Authors review the recently accumulating data, that curcumin constitutes a potent factor contributing to the more effective treatment of the bladder cancer.

Identification of Neoadjuvant Chemotherapy Response in Muscle-Invasive Bladder Cancer by Fourier-Transform Infrared Micro-Imaging

Simple Summary

Assessing the tumor response to chemotherapy is a paramount predictive step to improve patient care. Infrared spectroscopy probes the chemical composition of samples, and in combination with statistical multivariate processing, presents the capacity to highlight subtle molecular alterations associated with malignancy characteristics. Microscopic infrared imaging of tissue samples reveals spectral heterogeneity within histological structures, providing a new approach to characterize tumoral heterogeneity. We have taken advantage of the analytical capabilities of mid-infrared spectral imaging to implement a classification model to predict the response of a tumor to chemotherapy. Our development was demonstrated in muscle-invasive bladder cancer (MIBC) by comparing samples from responders and non-responders to neoadjuvant chemotherapy.

Abstract

Background: Neoadjuvant chemotherapy (NAC) improves survival in responder patients. However, for non-responders, the treatment represents an ineffective exposure to chemotherapy and its potential adverse events. Predicting the response to treatment is a major issue in the therapeutic management of patients, particularly for patients with muscle-invasive bladder cancer. Methods: Tissue samples of trans-urethral resection of bladder tumor collected at the diagnosis time, were analyzed by mid-infrared imaging. A sequence of spectral data processing was implemented for automatic recognition of informative pixels and scoring each pixel according to a continuous scale (from 0 to 10) associated with the response to NAC. The ground truth status of the responder or non-responder was based on histopathological examination of the samples. Results: Although the TMA spots of tumors appeared histologically homogeneous, the infrared approach highlighted spectral heterogeneity. Both the quantification of this heterogeneity and the scoring of the NAC response at the pixel level were used to construct sensitivity and specificity maps from which decision criteria can be extracted to classify cancerous samples. Conclusions: This proof-of-concept appears as the first to evaluate the potential of the mid-infrared approach for the prediction of response to neoadjuvant chemotherapy in MIBC tissues.

Discovery and Validation of Nitroxoline as a Novel STAT3 Inhibitor in Drug-resistant Urothelial Bladder Cancer

Repeated cycles of first-line chemotherapy drugs such as doxorubicin (DOX) and cisplatin (CIS) trigger frequent chemoresistance in recurrent urothelial bladder cancer (UBC). Nitroxoline (NTX), an antibiotic to treat urinary tract infections, has been recently repurposed for cancer treatment. Here we aimed to investigate whether NTX suppresses drug-resistant UBC and its molecular mechanism. The drug-resistant cell lines T24/DOX and T24/CIS were established by continual exposure of parental cell line T24 to DOX and CIS, respectively. T24/DOX and T24/CIS cells were resistant to DOX and CIS, respectively, but they were sensitive to NTX time- and dose-dependently. Overexpressions of STAT3 and P-glycoprotein (P-gp) were identified in T24/DOX and T24/CIS, which could be reversed by NTX. Western blot revealed that NTX downregulated p-STAT3, c-Myc, Cyclin D1, CDK4, CDK6, Bcl-xL, Mcl-1, and Survivin, which were further confirmed by Stattic, a selective STAT3 inhibitor. In vivo, NTX exhibited the significant anti-tumor effect in T24/DOX and T24/CIS tumor-bearing mice. These results suggested that NTX-induced P-gp reversal, G0/G1 arrest, and apoptosis in drug-resistant UBC were mediated by inhibition of STAT3 signaling. Our findings repurpose NTX as a novel STAT3 inhibitor to induce P-gp reversal, G0/G1 arrest, and apoptosis in drug-resistant UBC.

Hypomethylated RRBP1 Potentiates Tumor Malignancy and Chemoresistance in Upper Tract Urothelial Carcinoma

Ribosome-binding protein 1 (RRBP1) is a potential oncogene in several cancer types. However, the correlation between RRBP1 expression and the prognosis of patients with upper tract urothelial carcinoma (UTUC) remains unclear. In this study, we identified that RRBP1 is associated with carcinogenesis and metastasis in UTUC using a methylation profiling microarray. High correlations between RRBP1 and cancer stages, nodal metastasis status, molecular subtypes, and prognosis in bladder urothelial cancer (BLCA) were found. Aberrant DNA methylation in the gene body region of RRBP1 was determined in UTUC tissues by methylation-specific PCR. RRBP1 expression was significantly increased in UTUC tissues and cell lines, as determined by real-time PCR and immunohistochemistry. RRBP1 depletion significantly reduced BFTC909 cell growth induced by specific shRNA. On the other hand, molecular subtype analysis showed that the expression of RRBP1 was associated with genes related to cell proliferation, epithelial-mesenchymal transition, and basal markers. A patient-derived organoid model was established to analyze patients' responses to different drugs. The expression of RRBP1 was related to chemoresistance. Taken together, these results provide the first evidence that RRBP1 gene body hypomethylation predicts RRBP1 high expression in UTUC. The data highlight the importance of RRBP1 in UTUC malignancy and chemotherapeutic tolerance.

Rapidly Progressing Urothelial Carcinoma Due to a Rare TP53 (p.Arg110Pro) Mutation: A Case Report and Review of the Literature

We present a case of a 69-year-old male patient diagnosed with high grade (T₁ HG) urothelial carcinoma of the bladder who progressed rapidly towards muscle invasive disease and eventually death despite neoadjuvant chemotherapy and radical cystectomy. We postulate that this may be due to a deleterious underlying somatic gene mutation. Molecular pathologic data obtained on the initial, non-muscle invasive tumor and the final cystectomy specimen, revealed the same TP53 mutation (p.Arg110Pro) in both specimens with a variant allele frequency of 44%. The tumor was tested for 50 common gene mutations in urothelial carcinoma and no other identifiable DNA repair mutations were found, suggesting that this specific TP53 aberration, one that has never been reported in the bladder cancer literature, could be particularly deleterious. Knowing that bladder cancer cell lines that lack TP53 are more resistant to cisplatin and because the tumor lacked any other DNA mutation, this patient may have been a candidate for upfront surgery without neoadjuvant chemotherapy. In addition to histological analysis of the tumor, early molecular and cytogenetic characterization of resected tissue is essential in predicting progression and eventual prognosis of the disease based on identifiable gene mutations. Further comparative prospective studies are required to clarify the importance of molecular heterogeneity and subtyping in bladder cancer.

Circadian clock protein CRY1 prevents paclitaxel‑induced senescence of bladder cancer cells by promoting p53 degradation

Bladder cancer is a common tumor type of the urinary system, which has high levels of morbidity and mortality. The first‑line treatment is cisplatin‑based combination chemotherapy, but a significant proportion of patients relapse due to the development of drug resistance. Therapy‑induced senescence can act as a 'back‑up' response to chemotherapy in cancer types that are resistant to apoptosis‑based anticancer therapies. The circadian clock serves an important role in drug resistance and cellular senescence. The aim of the present study was to investigate the regulatory effect of the circadian clock on paclitaxel (PTX)‑induced senescence in cisplatin‑resistant bladder cancer cells. Cisplatin‑resistant bladder cancer cells were established via long‑term cisplatin incubation. PTX induced apparent senescence in bladder cancer cells as demonstrated via SA‑β‑Gal staining, but this was not observed in the cisplatin‑resistant cells. The cisplatin‑resistant cells entered into a quiescent state with prolonged circadian rhythm under acute PTX stress. It was identified that the circadian protein cryptochrome1 (CRY1) accumulated in these quiescent cisplatin‑resistant cells, and that CRY1 knockdown restored PTX‑induced senescence. Mechanistically, CRY1 promoted p53 degradation via increasing the binding of p53 with its ubiquitin E3 ligase MDM2 proto‑oncogene. These data suggested that the accumulated CRY1 in cisplatin‑resistant cells could prevent PTX‑induced senescence by promoting p53 degradation.

Strategies to Get Drugs across Bladder Penetrating Barriers for Improving Bladder Cancer Therapy

Bladder cancer is a significant public health concern and social burden due to its high recurrence risk. Intravesical drug instillation is the primary therapy for bladder cancer to prevent recurrence. However, the intravesical drug therapeutic effect is limited by bladder penetrating barriers. The inadequate intravesical treatment might cause the low drug concentration in lesions, resulting in a high recurrence/progression rate of bladder cancer. Many strategies to get drugs across bladder penetrating barriers have been developed to improve intravesical treatment, including physical and chemical methods. This review summarizes the classical and updated literature and presents insights into great therapeutic potential strategies to overcome bladder penetrating barriers for improving the intravesical treatment of bladder cancer.

The Cells and Extracellular Matrix of Human Amniotic Membrane Hinder the Growth and Invasive Potential of Bladder Urothelial Cancer Cells

Bladder cancer is one of the most common cancers among men in industrialized countries and on the global level incidence and mortality rates are increasing. In spite of progress in surgical treatment and chemotherapy, the prognosis remains poor for patients with muscle-invasive bladder cancer. Therefore, there is a great need for the development of novel therapeutic approaches. The human amniotic membrane (hAM) is a multi-layered membrane that comprises the innermost part of the placenta. It has unique properties that make it suitable for clinical use, such as the ability to promote wound healing and decrease scarring, low immunogenicity, and immunomodulatory, antimicrobial and anticancer properties. This study aimed to investigate the effect of (i) hAM-derived cells and (ii) hAM scaffolds on the growth dynamics, proliferation rate, and invasive potential of muscle-invasive bladder cancer T24 cells. Our results show that 24 and 48 h of co-culturing T24 cells with hAM-derived cells (at 1:1 and 1:4 ratios) diminished the proliferation rate of T24 cells. Furthermore, when seeded on hAM scaffolds, namely (1) epithelium of hAM (e-hAM), (2) basal lamina of hAM (denuded; d-hAM), and (3) stroma of hAM (s-hAM), the growth dynamic of T24 cells was altered and proliferation was reduced, even more so by the e-hAM scaffolds. Importantly, despite their muscle-invasive potential, the T24 cells did not disrupt the basal lamina of hAM scaffolds. Furthermore, we observed a decrease in the expression of epithelial-mesenchymal transition (EMT) markers N-cadherin, Snail and Slug in T24 cells grown on hAM scaffolds and individual T24 cells even expressed epithelial markers E-cadherin and occludin. Our study brings new knowledge on basic mechanisms of hAM affecting bladder carcinogenesis and the results serve as a good foundation for further research into the potential of hAM-derived cells and the hAM extracellular matrix to serve as a novel bladder cancer treatment.

Functional genetic variants of CTNNBIP1 predict platinum treatment response of Chinese epithelial ovarian cancer patients

Chemotherapy resistance remains a blockade for successful treatment and longer overall survival of patients with epithelial ovarian cancer (EOC). CTNNBIP1 is an inhibitor of β-catenin that is a chemotherapeutic target for EOC treatment. In the present study, we investigated associations between single nucleotide polymorphisms (SNPs) of CTNNBIP1 and platinum treatment response of Han Chinese EOC patients and subsequently performed functional prediction and validation of the resultant SNPs. We found that CTNNBIP1 rs935072 AT/TT variant genotypes were associated with platinum treatment response in the multivariate logistic regression analysis of EOC patients. Specifically, the CTNNBIP1 rs935072 AT/TT genotypes were associated with a decreased risk of developing chemoresistance ([adjusted odds ratio (OR)] = 0.89, 95% confidence interval (CI) = 0.82-0.97 and P=0.010), compared with the AA genotype. Further experiments showed that the underlying mechanism for the CTNNBIP1 rs935072 A>T change in chemotherapy treatment response resulted from a lower binding affinity of miR-27a-3p, thereby leading to up-regulation of the CTNNBIP1 expression. We further found that overexpression of CTNNBIP1 sensitized ovarian cancer cells to platinum treatment. Thus, the present study provides evidence that functional variants of CTNNBIP1 may regulate the expression of CTNNBIP1, a possible mechanism affecting platinum treatment response of EOC patients.

Curcumin-A Viable Agent for Better Bladder Cancer Treatment

Although the therapeutic armamentarium for bladder cancer has considerably widened in the last few years, severe side effects and the development of resistance hamper long-term treatment success. Thus, patients turn to natural plant products as alternative or complementary therapeutic options. One of these is curcumin, the principal component of Curcuma longa that has shown chemopreventive effects in experimental cancer models. Clinical and preclinical studies point to its role as a chemosensitizer, and it has been shown to protect organs from toxicity induced by chemotherapy. These properties indicate that curcumin could hold promise as a candidate for additive cancer treatment. This review evaluates the relevance of curcumin as an integral part of therapy for bladder cancer.

Targeting PI3K/Akt/mTOR signaling pathway by polyphenols: Implication for cancer therapy

Cancer is one of the biggest challenges facing medicine and its cure is regarded to be the Holy Grail of medicine. Therapy in cancer is consisted as various artificial cytotoxic agents and radiotherapy, and recently immunotherapy. Recently much attention has been directed to the use of natural occurring agents in cancer therapy. One of the main group of agents utilized in this regard is polyphenols which are found abundantly in berries, fruits and vegetables. Polyphenols show to exert direct and indirect effects in progression of cancer, angiogenesis, proliferation and enhancing resistance to treatment. One of the cellular pathways commonly affected by polyphenols is PI3K/Akt/mTOR pathway, which has far ranging effects on multiple key aspects of cellular growth, metabolism and death. In this review article, evidence regarding the biology of polyphenols in cancer via PI3K/Akt/mTOR pathway is discussed and their application on cancer pathophysiology in various types of human malignancies is shown.

Comparative effectiveness of radical cystectomy and radiotherapy without chemotherapy in frail patients with bladder cancer

Objectives: To evaluate cancer-specific (CSS) and overall survival (OS) in a group of frail patients who were treated with RT without chemotherapy and to compare them with a matched cohort of patients treated with RC.Methods: This study identified 71 patients treated with RT only for high-risk bladder cancer. Patients with metastatic (cN + or cM+) or non-resectable tumors (cT4) and those who received any form of chemotherapy were excluded. Patients where matched 1:1 using propensity scores which adjusted for the effects of age, clinical stage and age-adjusted Charlson comorbidity index (CCI). OS and CSS were evaluated using the Cox proportional hazards regression model and the Fine and Gray competing risk model.Results: In the overall population, RT was associated with worse OS (HR = 1.78, 95% CI = 1.15-2.77, p = 0.01) compared to RC, but not with CSS (HR 1.1, p = 0.74). In the matched cohort, RT was neither associated with OS nor CSS (p > 0.05) compared to RC. In the competing risk analyses no statistically significant association of any of the treatments was observed in the total or in the matched data set (p > 0.05).Conclusion: The use of RT may be an alternative option in well selected patients with limited disease who are considered unfit for systemic chemotherapy and RC. Future research should focus on improving patient selection and assess the quality-of-life as well as the need for reintervention in patients treated with RT.

The roles of glucose metabolic reprogramming in chemo- and radio-resistance

Reprogramming of cancer metabolism is a newly recognized hallmark of malignancy. The aberrant glucose metabolism is associated with dramatically increased bioenergetics, biosynthetic, and redox demands, which is vital to maintain rapid cell proliferation, tumor progression, and resistance to chemotherapy and radiation. When the glucose metabolism of cancer is rewiring, the characters of cancer will also occur corresponding changes to regulate the chemo- and radio-resistance of cancer. The procedure is involved in the alteration of many activities, such as the aberrant DNA repairing, enhanced autophagy, oxygen-deficient environment, and increasing exosomes secretions, etc. Targeting altered metabolic pathways related with the glucose metabolism has become a promising anti-cancer strategy. This review summarizes recent progress in our understanding of glucose metabolism in chemo- and radio-resistance malignancy, and highlights potential molecular targets and their inhibitors for cancer treatment.

Obatoclax, a BH3 Mimetic, Enhances Cisplatin-Induced Apoptosis and Decreases the Clonogenicity of Muscle Invasive Bladder Cancer Cells via Mechanisms That Involve the Inhibition of Pro-Survival Molecules as Well as Cell Cycle Regulators

Several studies by our group and others have determined that expression levels of Bcl-2 and/or Bcl-xL, pro-survival molecules which are associated with chemoresistance, are elevated in patients with muscle invasive bladder cancer (MI-BC). The goal of this study was to determine whether combining Obatoclax, a BH3 mimetic which inhibits pro-survival Bcl-2 family members, can improve responses to cisplatin chemotherapy, the standard of care treatment for MI-BC. Three MI-BC cell lines (T24, TCCSuP, 5637) were treated with Obatoclax alone or in combination with cisplatin and/or pre-miR-34a, a molecule which we have previously shown to inhibit MI-BC cell proliferation via decreasing Cdk6 expression. Proliferation, clonogenic, and apoptosis assays confirmed that Obatoclax can decrease cell proliferation and promote apoptosis in a dose-dependent manner. Combination treatment experiments identified Obatoclax + cisplatin as the most effective treatment. Immunoprecipitation and Western analyses indicate that, in addition to being able to inhibit Bcl-2 and Bcl-xL, Obatoclax can also decrease cyclin D1 and Cdk4/6 expression levels. This has not previously been reported. The combined data demonstrate that Obatoclax can inhibit cell proliferation, promote apoptosis, and significantly enhance the effectiveness of cisplatin in MI-BC cells via mechanisms that likely involve the inhibition of both pro-survival molecules and cell cycle regulators.

Radioresistance of cancer cells, integrin αvβ3 and thyroid hormone

Radioresistance is a substantial barrier to success in cancer management. A number of molecular mechanisms support radioresistance. We have shown experimentally that the thyroid hormone analogue receptor on the extracellular domain of integrin αvβ3 may modulate the state of radiosensitivity of tumor cells. Specifically, tetraiodothyroacetic acid (tetrac), a derivative of L-thyroxine (T₄), can reduce radioresistance in cancer cells. In this review, we list a number of intrinsic signal transduction molecules and other host factors that have been reported to support/induce radioresistance in cancer cells and that are also subject to control by T₄ through actions primarily initiated at integrin αvβ3. Additional preclinical evidence is needed to support these radioresistance-relevant actions of thyroid hormone.

Silencing circular RNA UVRAG inhibits bladder cancer growth and metastasis by targeting the microRNA-223/fibroblast growth factor receptor 2 axis

Circular RNA UVRAG (circUVRAG), a type of non-coding RNA, is derived and cyclized by part of the exon from the UVRAG gene. However, the role of circUVRAG in bladder cancer (BLCA) has not been reported. The purpose of the present study was therefore to characterize the role of circUVRAG in BLCA. Bioinformatics analysis showed interactive relationships among circUVRAG, microRNA-223 (miR-223), and fibroblast growth factor receptor 2 (FGFR2). Quantitative real-time PCR was used to detect the expression of circUVRAG in BLCA cell lines. UM-UC-3 cells were stably transfected with siRNA against circUVRAG, and cell proliferation and migration ability were tested using the CCK8 assay, clone formation, and Transwell assays in vitro. Tumor xenograft formation and metastasis were determined using nude mice. Fluorescence in situ hybridization was used to confirm the subcellular localization of circUVRAG, and the luciferase reporter assay was used to confirm the relationships among circUVRAG, miR-223, and FGFR2. Results showed that circUVRAG was upregulated in BLCA cell lines. Downregulation of circUVRAG expression suppressed proliferation and metastasis both in vitro and in vivo. Downregulation of circUVRAG suppressed FGFR2 expression by "sponging" miR-223, which was confirmed by rescue experiments and luciferase reporter assay. Overall, the results showed that downregulation of circUVRAG suppressed the aggressive biological phenotype of BLCA. Taken together, silencing circular RNA UVRAG inhibited bladder cancer growth and metastasis by targeting the miR-223/FGFR2 axis, which may provide a potential biomarker and therapeutic target for the management of BLCA.

C/EBPβ enhances platinum resistance of ovarian cancer cells by reprogramming H3K79 methylation

Chemoresistance is a major unmet clinical obstacle in ovarian cancer treatment. Epigenetics plays a pivotal role in regulating the malignant phenotype, and has the potential in developing therapeutically valuable targets that improve the dismal outcome of this disease. Here we show that a series of transcription factors, including C/EBPβ, GCM1, and GATA1, could act as potential modulators of histone methylation in tumor cells. Of note, C/EBPβ, an independent prognostic factor for patients with ovarian cancer, mediates an important mechanism through which epigenetic enzyme modifies groups of functionally related genes in a context-dependent manner. By recruiting the methyltransferase DOT1L, C/EBPβ can maintain an open chromatin state by H3K79 methylation of multiple drug-resistance genes, thereby augmenting the chemoresistance of tumor cells. Therefore, we propose a new path against cancer epigenetics in which identifying and targeting the key regulators of epigenetics such as C/EBPβ may provide more precise therapeutic options in ovarian cancer.

In ovarian cancer, the mechanism of chemoresistance is a key question. Here, the authors demonstrate that C/EBPβ and DOT1L together increase methylation of H3K79, which upregulates expression of oncogenic genes and drives poor platinum response and poor survival in ovarian cancer.