Gene expression of ERCC1 as a novel prognostic marker in advanced bladder cancer patients receiving cisplatin-based chemotherapy

Prognostic value of nucleotide excision repair and translesion DNA synthesis proteins in muscle-infiltrating bladder carcinoma

BACKGROUND

Cisplatin (CDDP) remains a key agent in the treatment of muscle-infiltrating bladder carcinoma (MIBC). However, a proportion of MIBC patients do not respond to chemotherapy, which may be caused by the increased repair of CDDP-induced DNA damage. The purpose of this study was to explore the prognostic value of proteins involved in nucleotide excision repair (NER) and translesion DNA synthesis (TLS) in MIBC patients.

METHODS

This is a retrospective analysis of 86 MIBC patients. The XPA, XPF, XPG, ERCC1, POLI, POLH and REV3L proteins were stained in primary bladder tumors and their levels were analyzed both in the total cohort and in a subgroup with metastatic urothelial carcinoma (mUC) that received gemcitabine and CDDP as a first-line therapy. Both cohorts were divided by percentage of cancer cells stained positive for each protein into subgroups with high and low expression. In the same manner, the combined expression of NER (XPA + ERCC1 + XPF + XPG) and TLS (POLI + POLH + REV3L), as the whole pathways, was analyzed.

RESULTS

Mortality was 89.5% at the median follow-up of 120.2 months. In the total cohort, patients with tumors stained positive for XPA, XPG and POLI had significantly worse overall survival (OS) compared to those with negative staining [hazard ratio (HR) = 0.60, 0.62 and 0.53, respectively]. Both XPG and POLI were independent prognostic factors in multivariate analyses (MVA). In addition, an increase in NER and TLS pathway expression was significantly associated with worse OS in the total cohort (HR = 0.54 and 0.60, respectively). In the mUC subgroup, high POLI expression was associated with significant deterioration of OS (HR = 0.56) in univariate analyses, and its independent prognostic value was shown in MVA.

CONCLUSIONS

Our study showed significant correlations between the tumor expression of XPG and POLI, as well as NER and TLS as the whole pathways, and inferior OS. Hence, they could constitute prognostic biomarkers and potentially promising therapeutic targets in MIBC. However, a prospective trial is required for further validation, thereby overcoming the limitations of this study.

Non-coding RNA transcripts, incredible modulators of cisplatin chemo-resistance in bladder cancer through operating a broad spectrum of cellular processes and signaling mechanism

Bladder cancer (BC) is a highly frequent neoplasm in correlation with significant rate of morbidity, mortality, and cost. The onset of BC is predominantly triggered by environmental and/or occupational exposures to carcinogens, such as tobacco. There are two distinct pathways by which BC can be developed, including non-muscle-invasive papillary tumors (NMIBC) and non-papillary (or solid) muscle-invasive tumors (MIBC). The Cancer Genome Atlas project has further recognized key genetic drivers of MIBC along with its subtypes with particular properties and therapeutic responses; nonetheless, NMIBC is the predominant BC presentation among the suffering individuals. Radical cystoprostatectomy, radiotherapy, and chemotherapy have been verified to be the common therapeutic interventions in metastatic tumors, among which chemotherapeutics are more conventionally utilized. Although multiple chemo drugs have been broadly administered for BC treatment, cisplatin is reportedly the most effective chemo drug against the corresponding malignancy. Notwithstanding, tumor recurrence is usually occurred following the consumption of cisplatin regimens, particularly due to the progression of chemo-resistant trait. In this framework, non-coding RNAs (ncRNAs), as abundant RNA transcripts arise from the human genome, are introduced to serve as crucial contributors to tumor expansion and cisplatin chemo-resistance in bladder neoplasm. In the current review, we first investigated the best-known ncRNAs, i.e. microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs), correlated with cisplatin chemo-resistance in BC cells and tissues. We noticed that these ncRNAs could mediate the BC-related cisplatin-resistant phenotype through diverse cellular processes and signaling mechanisms, reviewed here. Eventually, diagnostic and prognostic potential of ncRNAs, as well as their therapeutic capabilities were highlighted in regard to BC management.

Advancements in Urothelial Cancer Care: Optimizing Treatment for Your Patient

The standard treatment paradigm for muscle invasive bladder cancer has been neoadjuvant cisplatin-based chemotherapy followed by radical cystectomy. However, efforts are ongoing to personalize treatment by incorporating biomarkers to better guide treatment selection. In addition, bladder preservation strategies are aimed at avoiding cystectomy in well-selected patients. Similarly, in the metastatic urothelial cancer space, the standard frontline treatment option of platinum-based chemotherapy has changed with the availability of data from EV-302 trial, making the combination of enfortumab vedotin (EV) and pembrolizumab the preferred first-line treatment option. Here, we examine the optimization of treatment intensity and sequencing, focusing on the challenges and opportunities associated with EV/pembrolizumab therapy, including managing toxicities and exploring alternative dosing approaches. Together, these articles provide a comprehensive overview of contemporary strategies in bladder cancer management, highlighting the importance of individualized treatment approaches, ongoing research, and multidisciplinary collaboration to improve patient outcomes in this complex disease landscape.

Predictive and Prognostic Biomarkers and Tumor Antigens for Targeted Therapy in Urothelial Carcinoma

Urothelial carcinoma (UC) is the fourth most prevalent cancer amongst males worldwide. While patients with non-muscle-invasive disease have a favorable prognosis, 25% of UC patients present with locally advanced disease which is associated with a 10-15% 5-year survival rate and poor overall prognosis. Muscle-invasive bladder cancer (MIBC) is associated with about 50% 5 year survival when treated by radical cystectomy or trimodality therapy; stage IV disease is associated with 10-15% 5 year survival. Current therapeutic modalities for MIBC include neoadjuvant chemotherapy, surgery and/or chemoradiation, although patients with relapsed or refractory disease have a poor prognosis. However, the rapid success of immuno-oncology in various hematologic and solid malignancies offers new targets with tremendous therapeutic potential in UC. Historically, there were no predictive biomarkers to guide the clinical management and treatment of UC, and biomarker development was an unmet need. However, recent and ongoing clinical trials have identified several promising tumor biomarkers that have the potential to serve as predictive or prognostic tools in UC. This review provides a comprehensive summary of emerging biomarkers and molecular tumor targets including programmed death ligand 1 (PD-L1), epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), fibroblast growth factor receptor (FGFR), DNA damage response and repair (DDR) mutations, poly (ADP-ribose) polymerase (PARP) expression and circulating tumor DNA (ctDNA), as well as their clinical utility in UC. We also evaluate recent advancements in precision oncology in UC, while illustrating limiting factors and challenges related to the clinical application of these biomarkers in clinical practice.

Advances in diagnosis and treatment of bladder cancer

Bladder cancer remains a leading cause of cancer death worldwide and is associated with substantial impacts on patient quality of life, morbidity, mortality, and cost to the healthcare system. Gross hematuria frequently precedes the diagnosis of bladder cancer. Non-muscle-invasive bladder cancer (NMIBC) is managed initially with transurethral resection of a bladder tumor (TURBT), followed by a risk stratified approach to adjuvant intravesical therapy (IVe), and is associated with an overall survival of 90%. However, cure rates remain lower for muscle invasive bladder cancer (MIBC) owing to a variety of factors. NMIBC and MIBC groupings are heterogeneous and have unique pathological and molecular characteristics. Indeed, The Cancer Genome Atlas project identified genetic drivers and luminal and basal molecular subtypes of MIBC with distinct treatment responses. For NMIBC, IVe immunotherapy (primarily BCG) is the gold standard treatment for high grade and high risk NMIBC to reduce or prevent both recurrence and progression after initial TURBT; novel trials incorporate immune checkpoint inhibitors. IVe gene therapy and combination IVe chemotherapy have recently been completed, with promising results. For localized MIBC, essential goals are improving care and reducing morbidity following cystectomy or bladder preserving strategies. In metastatic disease, advances in understanding of the genomic landscape and tumor microenvironment have led to the implementation of immune checkpoint inhibitors, targeted treatments, and antibody-drug conjugates. Defining better selection criteria to identify the patients most likely to benefit from a specific treatment is an urgent need.

Inhibition of aldo-keto reductase 1C3 overcomes gemcitabine/cisplatin resistance in bladder cancer

Systemic chemotherapy with gemcitabine and cisplatin (GC) has been used for the treatment of bladder cancer in which androgen receptor (AR) signaling is suggested to play a critical role. However, its efficacy is often limited, and the prognosis of patients who develop resistance is extremely poor. Aldo-keto reductase 1C3 (AKR1C3), which is responsible for the production of a potent androgen, 5α-dihydrotestosterone (DHT), by the reduction of 5α-androstane-3α,17β-dione (5α-Adione), has been attracting attention as a therapeutic target for prostate cancer that shows androgen-dependent growth. By contrast, the role of AKR1C3 in bladder cancer remains unclear. In this study, we examined the effect of an AKR1C3 inhibitor on androgen-dependent proliferation and GC sensitivity in bladder cancer cells. 5α-Adione treatment induced the expression of AR and its downstream factor ETS-domain transcription factor (ELK1) in both T24 cells and newly established GC-resistant T24GC cells, while it did not alter AKR1C3 expression. AKR1C3 inhibitor 2j significantly suppressed 5α-Adione-induced AR and ELK1 upregulation, as did an AR antagonist apalutamide. Moreover, the combination of GC and 2j in T24GC significantly induced apoptotic cell death, suggesting that 2j could enhance GC sensitivity. Immunohistochemical staining in surgical specimens further revealed that strong expression of AKR1C3 was associated with significantly higher risks of tumor progression and cancer-specific mortality in patients with muscle-invasive bladder cancer. These results suggest that AKR1C3 inhibitors as adjunctive agents enhance the efficacy of GC therapy for bladder cancer.

Progress in systemic therapy for advanced-stage urothelial carcinoma

Despite recent advances, advanced-stage urothelial carcinoma (aUC) remains incurable, with 5-year survival rates of approximately 10%. Platinum-based chemotherapy has a major role as first-line therapy for most patients with aUC. The approval of the anti-PD-L1 antibody avelumab as maintenance therapy for patients without initial disease progression on platinum-based chemotherapy is an important development that has improved the survival outcomes of patients with this disease. Otherwise, the use of first-line immune-checkpoint inhibitors (ICIs) targeting PD-1 or PD-L1 has been restricted to patients who are ineligible for platinum-containing chemotherapy regimens. Other important developments include the FDA-accelerated approval of first-line enfortumab vedotin plus pembrolizumab for patients ineligible to receive cisplatin and the availability of FGFR inhibitors, enfortumab vedotin and sacituzumab govitecan for subsequent lines of therapy. Several research questions remain unaddressed including the lack of adequate biomarkers, how to assign priority to the different treatment options for individual patients and which agents can be effective as monotherapies. The future is promising with the emergence of modalities such as antibody-drug conjugate-like drugs, next-generation ICIs, bispecific antibodies and cellular therapies. In this Review, we summarize the evolution of systemic therapy for patients with aUC and provide insights into the unmet needs.

Integrated multiomics analysis and machine learning refine molecular subtypes and prognosis for muscle-invasive urothelial cancer

Muscle-invasive urothelial cancer (MUC), characterized by high aggressiveness and significant heterogeneity, is currently lacking highly precise individualized treatment options. We used a computational pipeline to synthesize multiomics data from MUC patients using 10 clustering algorithms, which were then combined with 10 machine learning algorithms to identify molecular subgroups of high resolution and develop a robust consensus machine learning-driven signature (CMLS). Through multiomics clustering, we identified three cancer subtypes (CSs) that are related to prognosis, with CS2 exhibiting the most favorable prognostic outcome. Subsequent screening enabled identification of 12 hub genes that constitute a CMLS with robust predictive power for prognosis. The low-CMLS group exhibited a more favorable prognosis and greater responsiveness to immunotherapy and was more likely to exhibit the "hot tumor" phenotype. The high-CMLS group had a poor prognosis and lower likelihood of benefitting from immunotherapy, but dasatinib and romidepsin may serve as promising treatments for them. Comprehensive analysis of multiomics data can offer important insights and further refine the molecular classification of MUC. Identification of CMLS represents a valuable tool for early prediction of patient prognosis and for screening potential candidates likely to benefit from immunotherapy, with broad implications for clinical practice.

Precision Medicine in Bladder Cancer: Present Challenges and Future Directions

Bladder cancer (BC) is characterized by significant histopathologic and molecular heterogeneity. The discovery of molecular pathways and knowledge of cellular mechanisms have grown exponentially and may allow for better disease classification, prognostication, and development of novel and more efficacious noninvasive detection and surveillance strategies, as well as selection of therapeutic targets, which can be used in BC, particularly in a neoadjuvant or adjuvant setting. This article outlines recent advances in the molecular pathology of BC with a better understanding and deeper focus on the development and deployment of promising biomarkers and therapeutic avenues that may soon make a transition into the domain of precision medicine and clinical management for patients with BC.

Current and Future Landscape of Perioperative Treatment for Muscle-Invasive Bladder Cancer

Cisplatin-based neoadjuvant chemotherapy followed by radical cystectomy is the current standard of care for muscle-invasive bladder cancer (MIBC). However, less than half of patients are candidates for this treatment, and 50% will develop metastatic disease. Adjuvant chemotherapy could be offered if neoadjuvant treatment has not been administered for suitable patients. It is important to reduce the risk of systemic recurrence and improve the prognosis of localized MIBC. Systemic therapy for metastatic urothelial carcinoma has evolved in recent years. Immune checkpoint inhibitors and targeted agents, such as antibody-drug conjugates or FGFR inhibitors, are new therapeutic alternatives and have shown their benefit in advanced disease. Currently, several clinical trials are investigating the role of these drugs, as monotherapy and in combination with chemotherapy, in the neoadjuvant and adjuvant settings with promising outcomes. In addition, the development of predictive biomarkers could predict responses to neoadjuvant therapies.

Potent molecular-targeted therapies for advanced esophageal squamous cell carcinoma

Esophageal cancer (EC) remains a public health concern with a high mortality and disease burden worldwide. Esophageal squamous cell carcinoma (ESCC) is a predominant histological subtype of EC that has unique etiology, molecular profiles, and clinicopathological features. Although systemic chemotherapy, including cytotoxic agents and immune checkpoint inhibitors, is the main therapeutic option for recurrent or metastatic ESCC patients, the clinical benefits are limited with poor prognosis. Personalized molecular-targeted therapies have been hampered due to the lack of robust treatment efficacy in clinical trials. Therefore, there is an urgent need to develop effective therapeutic strategies. In this review, we summarize the molecular profiles of ESCC based on the findings of pivotal comprehensive molecular analyses, highlighting potent therapeutic targets for establishing future precision medicine for ESCC patients, with the most recent results of clinical trials.

Predictive Biomarkers of Response to Neoadjuvant Therapy in Muscle Invasive Bladder Cancer

Neoadjuvant cisplatin-based chemotherapy is recommended prior to surgical removal of the bladder for patients with non-metastatic muscle invasive bladder cancer. Despite a survival benefit, approximately half of patients do not respond to chemotherapy and are exposed potentially unnecessarily to substantial toxicity and delay in surgery. Therefore, biomarkers to identify likely responders before initiating chemotherapy would be a helpful clinical tool. Furthermore, biomarkers may be able to identify patients who do not need subsequent surgery after clinical complete response to chemotherapy. To date, there are no clinically approved predictive biomarkers of response to neoadjuvant therapy. Recent advances in the molecular characterization of bladder cancer have shown the potential role for DNA damage repair (DDR) gene alterations and molecular subtypes to guide therapy, but these need validation from prospective clinical trials. This chapter reviews candidate predictive biomarkers of response to neoadjuvant therapy in muscle invasive bladder cancer.

Durvalumab Plus Olaparib in Previously Untreated, Platinum-Ineligible Patients With Metastatic Urothelial Carcinoma: A Multicenter, Randomized, Phase II Trial (BAYOU)

PURPOSE

Homologous recombination repair gene mutations (HRRm) are common in urothelial carcinoma (UC), rendering tumor cells sensitive to poly (ADP-ribose) polymerase (PARP) inhibition. We assessed efficacy and safety of durvalumab (anti-programmed cell death ligand-1) plus olaparib (PARP inhibitor) in patients with metastatic UC (mUC).

METHODS

This randomized, multicenter, double-blind, phase II trial enrolled untreated, platinum-ineligible patients with mUC. Patients (N = 154) were randomly assigned 1:1 to receive durvalumab (1,500 mg intravenously once every 4 weeks) plus olaparib (300 mg orally, twice daily) or durvalumab plus placebo. The primary end point was progression-free survival (PFS) assessed by investigators per RECIST version 1.1. Secondary end points included overall survival in all patients and PFS in patients with HRRm.

RESULTS

Overall, median PFS was 4.2 months (95% CI, 3.6 to 5.6) for durvalumab plus olaparib and 3.5 months (95% CI, 1.9 to 5.1) for durvalumab plus placebo (hazard ratio [HR], 0.94; 95% CI, 0.64 to 1.39; log-rank P value, .789). Median overall survival was 10.2 months (95% CI, 7.0 to 13.9) and 10.7 months (95% CI, 7.2 to 17.3), respectively (HR, 1.07; 95% CI, 0.72 to 1.61). In the 20% of patients with HRRm, median PFS was 5.6 months (95% CI, 1.9 to 8.1) and 1.8 months (95% CI, 1.7 to 2.2), respectively (HR, 0.18; 95% CI, 0.06 to 0.47). Treatment-related grade 3 or 4 adverse events occurred in 18% and 9% of patients, respectively.

CONCLUSION

Adding olaparib to durvalumab did not improve survival outcomes in an unselected mUC population. Efficacy outcomes with durvalumab were similar to those reported for other anti-programmed cell death-1/programmed cell death ligand-1 agents. However, the results of secondary analyses suggest a potential role for PARP inhibition in patients with UC harboring HRRm.

Complementary anti-cancer pathways triggered by inhibition of sideroflexin 4 in ovarian cancer

DNA damaging agents are a mainstay of standard chemotherapy for ovarian cancer. Unfortunately, resistance to such DNA damaging agents frequently develops, often due to increased activity of DNA repair pathways. Sideroflexin 4 (SFXN4) is a little-studied inner mitochondrial membrane protein. Here we demonstrate that SFXN4 plays a role in synthesis of iron sulfur clusters (Fe-S) in ovarian cancer cells and ovarian cancer tumor-initiating cells, and that knockdown of SFXN4 inhibits Fe-S biogenesis in ovarian cancer cells. We demonstrate that this has two important consequences that may be useful in anti-cancer therapy. First, inhibition of Fe-S biogenesis triggers the accumulation of excess iron, leading to oxidative stress. Second, because enzymes critical to multiple DNA repair pathways require Fe-S clusters for their function, DNA repair enzymes and DNA repair itself are inhibited by reduction of SFXN4. Through this dual mechanism, SFXN4 inhibition heightens ovarian cancer cell sensitivity to DNA-damaging drugs and DNA repair inhibitors used in ovarian cancer therapy, such as cisplatin and PARP inhibitors. Sensitization is achieved even in drug resistant ovarian cancer cells. Further, knockout of SFXN4 decreases DNA repair and profoundly inhibits tumor growth in a mouse model of ovarian cancer metastasis. Collectively, these results suggest that SFXN4 may represent a new target in ovarian cancer therapy.

Neoadjuvant Treatment in Muscle-Invasive Bladder Cancer: From the Beginning to the Latest Developments

Urothelial carcinoma of the bladder is one of the most prevalent cancers worldwide, diagnosed as muscle invasive in 25% of cases. Although several studies have demonstrated an overall 5% absolute survival benefit at 5 years with cisplatin-based combination neoadjuvant treatment, administration of chemotherapy prior to radical cystectomy (RC) in muscle-invasive bladder cancer (MIBC) patients is still a matter of debate. This may be due to the perceived modest survival benefit, cisplatin-based chemotherapy ineligibility, or fear of delaying potentially curative surgery in non-responders. However, immunotherapy and novel targeted therapies have shown to prolong survival in advanced disease and are under investigation in the neoadjuvant and adjuvant settings to reduce systemic relapse and improve cure rates. Genomic characterization of MIBC could help select the most effective chemotherapeutic regimen for the individual patient. Large cohort studies on neoadjuvant treatments with immune checkpoint inhibitors (ICIs) and molecular therapies, alone or combined with chemotherapy, are ongoing. In this review, we trace the development of neoadjuvant therapy in MIBC and explore recent advances that may soon change clinical practice.

Targeting Mechanisms of the DNA Damage Response (DDR) and DNA Repair by Natural Compounds to Improve cAT-Triggered Tumor Cell Death

Recently, we identified secalonic acid F (SA), 5-epi-nakijiquinone Q (NQ) and 5-epi-ilimaquinone (IQ) as natural compounds (NC) affecting mechanisms of the DNA damage response (DDR). Here, we further characterized their effects on DDR, DNA repair and cytotoxicity if used in mono- and co-treatment with conventional anticancer therapeutics (cAT) (cisplatin (Cis), doxorubicin (Doxo)) in vitro. All three NC influence the phosphorylation level of selected DDR-related factors (i.e., pCHK1, pKAP1, pP53, pRPA32) in mono- and/or co-treatment. Both SA and NQ attenuate the Cis- and Doxo-induced G2/M-phase arrest and effectively stimulate caspase-mediated apoptosis. Notably, SA impacts DNA repair as reflected by enhanced steady-state levels of Cis-(1,2-GpG)-DNA adducts and Doxo-induced DNA double-strand breaks (DSB). Moreover, SA decreased the mRNA and protein expression of the homologous recombination (HR)-related DSB repair factors RAD51 and BRCA1. Both SA and NQ promote Cis- and Doxo-induced cytotoxicity in an additive to synergistic manner (CI ≤ 1.0). Summarizing, we conclude that SA promotes cAT-driven caspase-dependent cell death by interfering with DSB repair and DDR-related checkpoint control mechanisms. Hence, SA is considered as the most promising lead compound to evaluate its therapeutic window in forthcoming pre-clinical in vivo studies.

Progress in the development of tissue-based biomarkers for urothelial cancer

INTRODUCTION

As the understanding of molecular mechanisms of bladder cancer advances, molecularly-guided precision medicine becomes increasingly relevant. Biomarkers play a critical role in this setting, predicting treatment response and identifying candidates for targeted therapies.

AREAS COVERED

Current literature on biomarkers in their role in disease prognosis, and response to neoadjuvant and adjuvant therapies. In non-muscle invasive bladder cancer, particular focus is on markers of disease progression, and response to intravesical therapy. In muscle invasive and advanced bladder cancer, particular emphasis is on markers associated with neoadjuvant chemotherapy, as well as systemic immunotherapy. We discuss current shortcomings and pitfalls in contemporary markers, and future avenues of prospective research.

EXPERT OPINION

The focus on biomarkers has moved from immunohistochemical analysis and tumor-related phenotypic changes to examining genetic alterations. Single marker analysis has been shown to be insufficient in predicting both disease course and response to therapy, and studies have shifted towards examining marker combinations and genetic classifiers. Ultimately, significant progress in implementing biomarkers into clinical guidelines remains elusive, largely due to lack of prospective studies in well-defined patient cohorts and with clinically-meaningful endpoints. Until then, despite their promising value, tissue markers should be limited to experimental settings and clinical trials.

SUMOylation Pattern Predicts Prognosis and Indicates Tumor Microenvironment Infiltration Characterization in Bladder Cancer

Background

SUMOylation is an important component of post-translational protein modifications (PTMs), and bladder cancer (BCa) is the ninth most common cancer around the world. But the comprehensive role of SUMOylation in shaping tumor microenvironment (TME) and influencing tumor clinicopathological features and also the prognosis of patients remains unclear.

Methods

Using the data downloaded from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO), we comprehensively evaluated the SUMOylation patterns of 570 bladder cancer samples, and systematically correlated these SUMOylation patterns with TME immune cell infiltrating characteristics. The SUMO score was constructed to quantify SUMOylation patterns of individuals using principal component analysis (PCA) algorithms.

Results

Two distinct SUMOylation patterns and gene clusters were finally determined. Significant differences in the prognosis of patients were found among two different SUMOylation patterns and gene clusters, so were in the mRNA transcriptome and the landscape of TME immune cell infiltration. We also established a set of scoring system named SUMO score to quantify the SUMOylation pattern of individuals with BCa, which was discovered to be tightly connected with tumor clinicopathological characteristics and could predict the prognosis of patients with BCa. Moreover, SUMO score was a considerable predictive indicator for the survival outcome independent of tumor mutation burden (TMB) and low SUMO score was related to better response to immunotherapy using PD-1 blockade. We also found that there existed a significant relationship between sensitivity to commonly used chemotherapy drugs and SUMO score. Finally, a nomograph based on five features, namely, SUMO score, age, gender, T category, and M category was constructed to predict the survival probability of patients with BCa in 1, 3, and 5 years, respectively.

Conclusions

Our work demonstrated and overviewed the complicated regulation mechanisms of SUMOylation in bladder cancer, and better understanding and evaluating SUMOylation patterns could be helpful in guiding clinical therapeutic strategy and improving the prognosis of patients with BCa.

SNCA correlates with immune infiltration and serves as a prognostic biomarker in lung adenocarcinoma

BACKGROUND

The SNCA gene is a critical gene in Parkinson's disease (PD) pathology. Accumulating evidence indicates that SNCA is involved in tumorigenesis; however, the role of SNCA in lung adenocarcinoma (LUAD) remains unclear. This study aimed to explore the potential value of SNCA as a prognostic and diagnostic molecular marker in LUAD.

METHODS

In this study, we explored the expression pattern, prognostic value, and promoter methylation status of SNCA in LUAD based on Oncomine, UALCAN, and Kaplan-Meier Plotter. Then, using TIMER, we investigated the correlation between SNCA expression and immune infiltration. And cBioPortal were used to analysis the correlation between SNCA expression and immune checkpoint. The transcriptome data of A549 cells overexpressing SNCA were used to further study the potential immune role of SNCA in LUAD. The effect of SNCA on proliferation of A549 cells were evaluated by CCK-8, EdU and colony formation. Finally, LUAD cell lines treated with 5-aza-dC were used to explore the correlation between increased promoter methylation and downregulated mRNA expression of SNCA.

RESULTS

In general, the expression level of SNCA in LUAD tissue was lower than that in normal tissue, and high expression of SNCA was related to better prognosis. There were significant positive correlations between SNCA expression and immune infiltrations, including CD8+ T cells, macrophages, neutrophils, dendritic cells, B cells, and CD4+ T cells, and immune checkpoints, suggesting that immune infiltration was one of the reasons for the influence of SNCA on prognosis in LUAD. The transcriptome data of A549 cells overexpressing SNCA were further used to screen the relevant immune-related genes regulated by SNCA. Enrichment analysis confirmed that SNCA participates in the PI3K-AKT signaling pathway and other key tumor signaling pathways and regulates the expression of MAPK3, SRC, PLCG1, and SHC1. Cellular proliferation assay showed that SNCA could inhabit the growth of A549 cells via inhibiting activity of PI3K/AKT/ mTOR pathway. Finally, analysis of the methylation level of SNCA promoter showed that the promoter methylation negatively correlated with mRNA level. The expression of SNCA in LUAD cell lines was significantly upregulated by treatment with 5-aza-dC.

CONCLUSION

High methylation of SNCA promoter in LUAD is one of the reasons for the downregulation of SNCA mRNA level. Given that SNCA could inhibit the proliferation of A549 cells and correlates with immune infiltrates, it may serve as a prognostic biomarker in LUAD.

Biomarkers in muscle invasive bladder cancer

Muscle invasive bladder cancer (MIBC) carries a poor prognosis with a 5-year overall survival rate of 40-50%. For localized disease, radical treatment options are cystectomy or radiotherapy with or without a radiosensitiser. Neoadjuvant or adjuvant chemotherapy is often delivered in addition to either. Metastatic disease can be treated with palliative systemic chemotherapy or immunotherapy. Standard clinicopathological information is insufficient to guide treatment decisions in several clinical scenarios in MIBC and there has been substantial effort to identify predictive and prognostic biomarkers. Despite this, no biomarker has been sufficiently qualified in prospective clinical trials to justify routine use. In this chapter we discuss these biomarkers and provide insight into the significant unmet need for robust biomarkers to inform treatment decisions and ultimately improve outcomes for bladder cancer patients.

Genomic Landscape of Vinflunine Response in Metastatic Urothelial Cancer

Simple Summary

Few metastatic urothelial cancer patients achieve durable clinical benefit with vinflunine. Predictive biomarkers to help to identify better treatment strategies are extremely needed. The objective of this study was to identify molecular differences between extreme responders to vinflunine in urothelial cancer. Genomic and immune markers are potentially useful identifying patients that may achieve greater benefit with vinflunine.

Abstract

Background and Aims: Metastatic urothelial carcinoma (mUC) remains an incurable disease with limited treatment options after platinum-based chemotherapy and immune checkpoint blockade (ICB). Vinflunine has shown a modest increase in overall survival and remains a therapeutic option for chemo- and immunotherapy refractory tumours. However, biomarkers that could identify responding patients to vinflunine and possible alternative therapies after failure to treatment are still missing. In this study, we aimed to identify potential genomic biomarkers of vinflunine response in mUC patient samples and potential management alternatives. Methods: Formalin-fixed paraffin-embedded samples of mUC patients (n = 23) from three university hospitals in Spain were used for genomic targeted-sequencing and transcriptome (using the Immune Profile panel by NanoString) analyses. Patients who received vinflunine after platinum-based chemotherapy failure were classified in non-responders (NR: progressive disease ≤ 3 months; n= 11) or responders (R: response ≥ 6 months; n = 12). Results: Genomic characterization revealed that the most common alteration, TP53 mutations, had comparable frequency in R (6/12; 50%) and NR (4/11; 36%). Non-synonymous mutations in KTM2C (4/12; 33.3%), PIK3CA (3/12; 25%) and ARID2 (3/12; 25%) were predominantly associated with response. No significant difference was observed in tumour mutational burden (TMB) between R and NR patients. The NR tumours showed increased expression of diverse immune-related genes and pathways, including various interferon gamma-related genes. We also identified increased MAGEA4 expression as a potential biomarker of non-responding tumours to vinflunine treatment. Conclusions: Our data may help to identify potential genomic biomarkers of response to vinflunine. Moreover, tumours refractory to vinflunine showed immune signatures potentially associated with response to ICB. Extensive validation studies, including longitudinal series, are needed to corroborate these findings.

Printer center nanoparticles alter the DNA repair capacity of human bronchial airway epithelial cells

Nano-enabled, toner-based printing equipment emit nanoparticles during operation. The bioactivity of these nanoparticles as documented in a plethora of published toxicological studies raises concerns about their potential health effects. These include pro-inflammatory effects that can lead to adverse epigenetic alterations and cardiovascular disorders in rats. At the same time, their potential to alter DNA repair pathways at realistic doses remains unclear. In this study, size-fractionated, airborne particles from a printer center in Singapore were sampled and characterized. The PM_0.1 size fraction (particles with an aerodynamic diameter less than 100 nm) of printer center particles (PCP) were then administered to human lung adenocarcinoma (Calu-3) or lymphoblastoid (TK6) cells. We evaluated plasma membrane integrity, mitochondrial activity, and intracellular reactive oxygen species (ROS) generation. Moreover, we quantified DNA damage and alterations in the cells' capacity to repair 6 distinct types of DNA lesions. Results show that PCP altered the ability of Calu-3 cells to repair 8oxoG:C lesions and perform nucleotide excision repair, in the absence of acute cytotoxicity or DNA damage. Alterations in DNA repair capacity have been correlated with the risk of various diseases, including cancer, therefore further genotoxicity studies are needed to assess the potential risks of PCP exposure, at both occupational settings and at the end-consumer level.

ERCC1 19007 Polymorphism in Greek Patients with Advanced Urothelial Cancer Treated with Platinum-Based Chemotherapy: Effect of the Changing Treatment Paradigm: A Cohort Study by the Hellenic GU Cancer Group

We previously showed that ERCC1 19007 C>T polymorphism was associated with cancer-specific survival (CSS) after platinum-based chemotherapy in patients with advanced urothelial cancer (aUC). We aimed to confirm this association in a different cohort of patients. Genotyping of the 19007C>T polymorphism was carried out by polymerase chain reaction (PCR) amplification and restriction fragment length polymorphism (RFLP) in 98 aUC patients, treated with platinum-based chemotherapy. Median age of the patients was 68.8, 13.3% of them were female, 90.8% had ECOG PS of 0 or 1, and 48% received cisplatin-based chemotherapy. In addition to chemotherapy, 32.7% of the patients received immunotherapy, and 19.4% vinflunine. Eighty-one patients (82.7%) were carriers of the 19007T polymorphic allele: 46 (46.9%) were heterozygotes, and 35 (35.7%) were homozygotes. The ERCC1 polymorphism was not associated with CSS, progression-free (PFS), or overall (OS) survival in the total population. Nevertheless, there was a significant interaction between the prognostic significance of ERCC1 polymorphism and the use of modern immunotherapy: the T allele was associated with worse outcome in patients who received chemotherapy only, while this association was lost in patients who received both chemotherapy and immune checkpoint inhibitors. Our study suggests that novel therapies may influence the significance of ERCC1 polymorphism in patients with aUC. Its determination may be useful in the changing treatment landscape of the disease.

Cisplatin-induced neurotoxicity involves the disruption of serotonergic neurotransmission

Neurotoxicity is a frequent side effect of cisplatin (CisPt)-based anticancer therapy whose pathophysiology is largely vague. Here, we exploited C. elegans as a 3R-compliant in vivo model to elucidate molecular mechanisms contributing to CisPt-induced neuronal dysfunction. To this end, we monitored the impact of CisPt on various sensory functions as well as pharyngeal neurotransmission by recording electropharyngeograms (EPGs). CisPt neither affected food and odor sensation nor mechano-sensation, which involve dopaminergic and glutaminergic neurotransmission. However, CisPt reduced serotonin-regulated pharyngeal pumping activity independent of changes in the morphology of related neurons. CisPt-mediated alterations in EPGs were fully rescued by addition of serotonin (5-HT) (≤ 2 mM). Moreover, the CisPt-induced pharyngeal injury was prevented by co-incubation with the clinically approved serotonin re-uptake inhibitory drug duloxetine. A protective effect of 5-HT was also observed with respect to CisPt-mediated impairment of another 5-HT-dependent process, the egg laying activity. Importantly, CisPt-induced apoptosis in the gonad and learning disability were not influenced by 5-HT. Using different C. elegans mutants we found that CisPt-mediated (neuro)toxicity is independent of serotonin biosynthesis and re-uptake and likely involves serotonin-receptor subtype 7 (SER-7)-related functions. In conclusion, by measuring EPGs as a surrogate parameter of neuronal dysfunction, we provide first evidence that CisPt-induced neurotoxicity in C. elegans involves 5-HT-dependent neurotransmission and SER-7-mediated signaling mechanisms and can be prevented by the clinically approved antidepressant duloxetine. The data highlight the particular suitability of C. elegans as a 3R-conform in vivo model in molecular (neuro)toxicology and, moreover, for the pre-clinical identification of neuroprotective candidate drugs.

Molecular markers of systemic therapy response in urothelial carcinoma

Identification of reliable molecular biomarkers that can complement clinical practice represents a fascinating challenge in any cancer field. Urothelial carcinoma is a very heterogeneous disease and responses to systemic therapies, and outcomes after radical cystectomy are difficult to predict. Advances in molecular biology such as next generation sequencing and whole genome or transcriptomic analysis provide promising platforms to achieve a full understanding of the biology behind the disease and can identify emerging predictive biomarkers. Moreover, the ability to categorize patients' risk of recurrence after curative treatment, or even predict benefit from a conventional or targeted therapies, represents a compelling challenge that may reshape both selection for tailored treatment and disease monitoring. Progress has been made but currently no molecular biomarkers are used in the clinical setting to predict response to systemic agents in either neoadjuvant or adjuvant settings highlighting a relevant unmet need. Here, we aim to present the emerging role of molecular biomarkers in predicting response to systemic agents in urothelial carcinoma.

The developmental origin of cancers defines basic principles of cisplatin resistance

Cisplatin-based chemotherapy has been used for more than four decades as a standard therapeutic option in several tumor entities. However, being a multifaceted and heterogeneous phenomenon, inherent or acquired resistance to cisplatin remains a major obstacle during the treatment of several solid malignancies and inevitably results in disease progression. Hence, we felt there was an urgent need to evaluate common mechanisms between multifarious cancer entities to identify patient-specific therapeutic strategies. We found joint molecular and (epi)genetic resistance mechanisms and specific cisplatin-induced mutational signatures that depended on the developmental origin (endo-, meso-, ectoderm) of the tumor tissue. Based on the findings of thirteen tumor entities, we identified three resistance groups, where Group 1 (endodermal origin) prominently indicates NRF2-pathway activation, Group 2 (mesodermal origin, primordial germ cells) shares elevated DNA repair mechanisms and decreased apoptosis induction, and Group 3 (ectodermal and paraxial mesodermal origin) commonly presents deregulated apoptosis induction and alternating pathways as the main cisplatin-induced resistance mechanisms. This review further proposes potential and novel therapeutic strategies to improve the outcome of cisplatin-based chemotherapy.

Platinum Complexes in Colorectal Cancer and Other Solid Tumors

Simple Summary

Cisplatin is successfully used for the treatment of various solid cancers. Unfortunately, it shows no activity in colorectal cancer. The resistance phenotype of colorectal cancer cells is mainly caused by alterations in p53-controlled DNA damage signaling and/or defects in the cellular mismatch repair pathway. Improvement of platinum-based chemotherapy in cisplatin-unresponsive cancers, such as colorectal cancer, might be achieved by newly designed cisplatin analogues, which retain activity in unresponsive tumor cells. Moreover, a combination of cisplatin with biochemical modulators of DNA damage signaling might sensitize cisplatin-resistant tumor cells to the drug, thus providing another strategy to improve cancer therapy.

Abstract

Cisplatin is one of the most commonly used drugs for the treatment of various solid neoplasms, including testicular, lung, ovarian, head and neck, and bladder cancers. Unfortunately, the therapeutic efficacy of cisplatin against colorectal cancer is poor. Various mechanisms appear to contribute to cisplatin resistance in cancer cells, including reduced drug accumulation, enhanced drug detoxification, modulation of DNA repair mechanisms, and finally alterations in cisplatin DNA damage signaling preventing apoptosis in cancer cells. Regarding colorectal cancer, defects in mismatch repair and altered p53-mediated DNA damage signaling are the main factors controlling the resistance phenotype. In particular, p53 inactivation appears to be associated with chemoresistance and poor prognosis. To overcome resistance in cancers, several strategies can be envisaged. Improved cisplatin analogues, which retain activity in resistant cancer, might be applied. Targeting p53-mediated DNA damage signaling provides another therapeutic strategy to circumvent cisplatin resistance. This review provides an overview on the DNA repair pathways involved in the processing of cisplatin damage and will describe signal transduction from cisplatin DNA lesions, with special attention given to colorectal cancer cells. Furthermore, examples for improved platinum compounds and biochemical modulators of cisplatin DNA damage signaling will be presented in the context of colon cancer therapy.

RNA Expression of DNA Damage Response Genes in Muscle-Invasive Bladder Cancer: Influence on Outcome and Response to Adjuvant Cisplatin-Based Chemotherapy

BACKGROUND

Perioperative cisplatin-based chemotherapy (CBC) can improve the outcome of patients with muscle-invasive bladder cancer (MIBC), but it is still to be defined which patients benefit. Mutations in DNA damage response genes (DDRG) can predict the response to CBC. The value of DDRG expression as a marker of CBC treatment effect remains unclear.

MATERIAL AND METHODS

RNA expression of the nine key DDRG (BCL2, BRCA1, BRCA2, ERCC2, ERCC6, FOXM1, RAD50, RAD51, and RAD52) was assessed by qRT-PCR in a cohort of 61 MICB patients (median age 66 y, 48 males, 13 females) who underwent radical cystectomy in a tertiary care center. The results were validated in the The Cancer Genome Atlas (TCGA) cohort of MIBC (n = 383). Gene expression was correlated with disease-free survival (DFS) and overall survival (OS). Subgroup analyses were performed in patients who received adjuvant cisplatin-based chemotherapy (ACBC) (Mannheim n = 20 and TCGA n = 75).

RESULTS

Low expression of RAD52 was associated with low DFS in both the Mannheim and the TCGA cohorts (Mannheim: p = 0.039; TCGA: p = 0.017). This was especially apparent in subgroups treated with ACBC (Mannheim: p = 0.0059; TCGA: p = 0.012). Several other genes showed an influence on DFS in the Mannheim cohort (BRCA2, ERCC2, FOXM1) where low expression was associated with poor DFS (p < 0.05 for all). This finding was not fully supported by the data in the TCGA cohort, where high expression of FOXM1 and BRCA2 correlated with poor DFS.

CONCLUSION

Low expression of RAD52 correlated with decreased DFS in the Mannheim and the TCGA cohort. This effect was especially pronounced in the subset of patients who received ACBC, making it a promising indicator for response to ACBC on the level of gene expression.

High-Throughput Screening Platform for Nanoparticle-Mediated Alterations of DNA Repair Capacity

The potential genotoxic effects of engineered nanomaterials (ENMs) may occur through the induction of DNA damage or the disruption of DNA repair processes. Inefficient DNA repair may lead to the accumulation of DNA lesions and has been linked to various diseases, including cancer. Most studies so far have focused on understanding the nanogenotoxicity of ENM-induced damages to DNA, whereas the effects on DNA repair have been widely overlooked. The recently developed fluorescence multiplex-host-cell reactivation (FM-HCR) assay allows for the direct quantification of multiple DNA repair pathways in living cells and offers a great opportunity to address this methodological gap. Herein an FM-HCR-based method is developed to screen the impact of ENMs on six major DNA repair pathways using suspended or adherent cells. The sensitivity and efficiency of this DNA repair screening method were demonstrated in case studies using primary human small airway epithelial cells and TK6 cells exposed to various model ENMs (CuO, ZnO, and Ga2O3) at subcytotoxic doses. It was shown that ENMs may inhibit nucleotide-excision repair, base-excision repair, and the repair of oxidative damage by DNA glycosylases in TK6 cells, even in the absence of significant genomic DNA damage. It is of note that the DNA repair capacity was increased by some ENMs, whereas it was suppressed by others. Overall, this method can be part of a multitier, in vitro hazard assessment of ENMs as a functional, high-throughput platform that provides insights into the interplay of the properties of ENMs, the DNA repair efficiency, and the genomic stability.

Use of C. elegans as a 3R-compliant in vivo model for the chemoprevention of cisplatin-induced neurotoxicity

Anticancer therapeutics can provoke severe side effects that impair the patient's quality of life. A frequent dose-limiting side effect of platinum-based anticancer therapy is neurotoxicity. Its pathophysiology is poorly understood, and effective preventive or therapeutic measures are missing. Therefore, elucidation of the molecular mechanism of platinating drug-induced neurotoxicity and the development of preventive strategies is urgently needed. To this end, we aim to use C. elegans as a 3R-compliant in vivo model. The 3R principles were conceived for animal welfare in science concerning animal experiments, which should be replaced, reduced or refined. We can analytically demonstrate dose-dependent uptake of cisplatin (CisPt) in C. elegans, as well as genotoxic and cytotoxic effects based on DNA adduct formation (i.e., 1,2-GpG intrastrand crosslinks), induction of apoptosis, and developmental toxicity. Measuring the impairment of pharyngeal pumping as a marker of neurotoxicity, we found that especially CisPt reduces the pumping frequency at concentrations where basal and touch-provoked movement were not yet affected. CisPt causes glutathione (GSH) depletion and RNAi-mediated knockdown of the glutamate-cysteine ligase GCS-1 aggravates the CisPt-induced inhibition of pharyngeal pumping. Moreover, N-acetylcysteine (NAC) mitigated CisPt-triggered toxicity, indicating that GSH depletion contributes to the CisPt-induced pharyngeal damage. In addition to NAC, amifostine (WR1065) also protected the pharynx of C. elegans from the toxic effects of CisPt. Measuring pharyngeal activity by the electrophysiological recording of neurotransmission in the pharynx, we confirmed that CisPt is neurotoxic in C. elegans and that NAC is neuroprotective in the nematode. The data support the hypothesis that monitoring the pharyngeal activity of C. elegans is a useful surrogate marker of CisPt-induced neurotoxicity. In addition, a low GSH pool reduces the resistance of neurons to CisPt treatment, and both NAC and WR1065 are capable of attenuating platinum-induced neurotoxicity during post-incubation in C. elegans. Overall, we propose C. elegans as a 3R-compliant in vivo model to study the molecular mechanisms of platinum-induced neurotoxicity and to explore novel neuroprotective therapeutic strategies to alleviate respective side effects of platinum-based cancer therapy.

Management of Clinically Regional Node-Positive Urothelial Carcinoma of the Bladder

PURPOSE OF REVIEW

Clinically regional node-positive (cN+) urothelial carcinoma of the bladder requires a multi-modal management approach amidst growing recognition that it represents a spectrum of disease. Herein, we review the contemporary evidence for the natural history, evaluation, and management of clinically regional node-positive urothelial carcinoma of the bladder, highlighting recent changes in lymph node staging.

RECENT FINDINGS

Despite advances in techniques, cross-sectional imaging remains relatively insensitive for the detection of lymph node metastases. Recent changes to nodal staging that distinguish between cN1, cN2-3, and non-regional lymph node metastases reflect an increasing understanding that node-positive disease is heterogeneous and its management must be individualized according to nodal staging. Systemic therapy remains the initial management strategy, either alone or in conjunction with radiotherapy, with choice and sequencing of agents extrapolated from studies of metastatic disease. Consolidative radical cystectomy is an option for patients with disease response to upfront systemic therapy, and several series demonstrate a subset of patients with favorable oncologic outcomes. The comparative effectiveness of radiotherapy and radical cystectomy as local therapy remains an important evidence gap. Future studies that identify predictive biomarkers will help inform optimal choice of systemic therapy. The management of clinically regional node-positive disease requires a multimodal approach comprising both systemic and local therapy, tailored to the patient and to disease response. While choice of systemic therapy will be informed by ongoing studies in patients with metastatic disease, including the elucidation of predictive biomarkers, the comparative effectiveness of local therapies remains an important evidence gap.

Advances in bladder cancer biology and therapy

The field of research in bladder cancer has seen significant advances in recent years. Next-generation sequencing has identified the genes most mutated in bladder cancer. This wealth of information allowed the definition of driver mutations, and identification of actionable therapeutic targets, as well as a clearer picture of patient prognosis and therapeutic direction. In a similar vein, our understanding of the cellular aspects of bladder cancer has grown. The identification of the cellular geography and the populations of different cell types and quantifications of normal and abnormal cell types in tumours provide a better prediction of therapeutic response. Non-invasive methods of diagnosis, including liquid biopsies, have seen major advances as well. These methods will likely find considerable utility in assessing minimal residual disease following treatment and for early-stage diagnosis. A significant therapeutic impact on patients with bladder cancer is found in the use of immune checkpoint inhibitor therapeutics. These therapeutics have been shown to cure some patients with bladder cancer and significantly decrease adverse events. These developments provide patients with better monitoring opportunities, unique therapeutic options and greater hope for prolonged survival.

EHHADH contributes to cisplatin resistance through regulation by tumor-suppressive microRNAs in bladder cancer

Background

Cisplatin-based chemotherapy is recommended as the primary treatment for advanced bladder cancer (BC) with unresectable or metastatic disease. However, the benefits are limited due to the acquisition of drug resistance. The mechanisms of resistance remain unclear. Although there are some reports that some molecules are associated with cisplatin resistance in advanced BC, those reports have not been fully investigated. Therefore, we undertook a new search for cisplatin resistance-related genes targeted by tumor suppressive microRNAs as well as genes that were downregulated in cisplatin-resistant BC cells and clinical BC tissues.

Methods

First, we established cisplatin-resistant BOY and T24 BC cell lines (CDDP-R-BOY, CDDP-R-T24). Then, Next Generation Sequence analysis was performed with parental and cisplatin-resistant cell lines to search for the microRNAs responsible for cisplatin resistance. We conducted gain-of-function analysis of microRNAs and their effects on cisplatin resistance, and we searched target genes comprehensively using Next Generation mRNA sequences.

Results

A total of 28 microRNAs were significantly downregulated in both CDDP-R-BOY and CDDP-R-T24. Among them, miR-486-5p, a tumor suppressor miRNA, was negatively correlated with the TNM classification of clinical BC samples in The Cancer Genome Atlas (TCGA) database. Transfection of miRNA-486-5p significantly inhibited cancer cell proliferation, migration, and invasion, and also improved the cells’ resistance to cisplatin. Among the genes targeted by miRNA-486-5p, we focused on enoyl-CoA, hydratase/3-hydroxyacyl CoA dehydrogenase (EHHADH), which is involved in the degradation of fatty acids. EHHADH was directly regulated by miRNA-486-5p as determined by a dual-luciferase reporter assay. Loss-of-function study using EHHADH si-RNA showed significant inhibitions of cell proliferation, migration, invasion and the recovery of cisplatin sensitivity.

Conclusion

Identification of EHHADH as a target of miRNA-486-5p provides novel insights into the potential mechanisms of cisplatin resistance in BC.

MMP-7 Serum and Tissue Levels Are Associated with Poor Survival in Platinum-Treated Bladder Cancer Patients

Chemotherapy resistance is a main cause of therapeutic failure and death in bladder cancer. With the approval of immune checkpoint inhibitors, prediction of platinum treatment became of great clinical importance. Matrix metalloproteinase-7 (MMP-7) was shown to be involved in cisplatin resistance. Therefore, tissue and circulating MMP-7 levels were evaluated in 124 bladder cancer patients who received postoperative platinum-based chemotherapy. Tissue MMP-7 levels were analyzed by immunohistochemistry in 72 formalin-fixed, paraffin-embedded chemo-naïve tumor samples, while MMP-7 serum concentrations were determined in 132 serum samples of an independent cohort of 52 patients. MMP-7 tissue and serum levels were correlated with clinicopathological and follow-up data. MMP-7 gene expression was determined by RT-qPCR in 20 urothelial cancer cell lines and two non-malignant urothelial cell lines. MMP-7 was overexpressed in RT-112 and T-24 cells by stable transfection, to assess its functional involvement in platinum sensitivity. High MMP-7 tissue expression and pretreatment serum concentrations were independently associated with poor overall survival (tissue HR = 2.296, 95%CI = 1.235–4.268 and p = 0.009; serum HR = 2.743, 95%CI = 1.258–5.984 and p = 0.011). Therefore, MMP-7 tissue and serum analysis may help to optimize therapeutic decisions. Stable overexpression in RT-112 and T-24 cells did not affect platinum sensitivity.

Neoadjuvant Chemotherapy Before Radical Cystectomy: Why We Must Adhere?

AIM

This study provides a critical literature review on state-of-the-art and novel strategies in the field of neoadjuvant treatments for muscle-invasive bladder cancer (MIBC).

METHODS

A nonsystematic literature review was performed using PubMed, Scopus and Clinical Trials.gov to retrieve papers related to neoadjuvant treatments for MIBC over the past 15 years. Prospective and retrospective studies were included.

RESULTS

Platinum-based treatment is the gold standard and mainly consists of a combination of cisplatin with vinblastine, methotrexate, doxorubicin, gemcitabine, adriamycin or even epirubicin. The 5- year absolute overall survival benefit of MVAC is 5% and the absolute disease-free survival improves by 9%. CMV treatment is associated with a 10-year overall survival improving from 30% to 36% and a 16% reduction in mortality. Gemcitabine and cisplatin regimen provides complete response in 20% of cases, with non-inferior oncological outcomes compared to MVAC regimen. Recent prospective trials investigating neoadjuvant immunotherapy show a high rate of complete response, from 29% with atezolizumab to 39.5% with pembrolizumab. The tyrosine kinase inhibitor pathway is being explored and could offer an interesting strategy to improve survival outcomes.

CONCLUSION

Available evidence suggests better oncological outcomes for MIBC patients receiving neoadjuvant treatment before radical cystectomy. While MVAC remains the standard of care in cisplatin eligible patients, novel strategies are under development for cisplatin-ineligible patients, whereby immunotherapy seems to hold great promise.

Differential gene expression in cisplatin-resistant and -sensitive testicular germ cell tumor cell lines

Testicular germ cell tumors (TGCTs) represent a well curable malignity due to their exceptional response to cisplatin (CDDP). Despite remarkable treatment results, approximately 5% of TGCT patients develop CDDP resistance and die. Exceptional curability makes TGCTs a highly valuable model system for studying the molecular mechanisms of CDDP sensitivity. Our study was aimed at revealing difference in gene expression between the CDDP-resistant and -sensitive TGCT cell lines, and hence at identifying candidate genes that could serve as potential biomarkers of CDDP response. Using gene expression array, we identified 281 genes that are differentially expressed in CDDP-resistant compared to -sensitive TGCT cell lines. The expression of 25 genes with the highest fold change was validated by RT-qPCR. Of them, DNMT3L, GAL, IGFBP2, IGFBP7, L1TD1, NANOG, NTF3, POU5F1, SOX2, WNT6, ZFP42, ID2, PCP4, SLC40A1 and TRIB3, displayed comparable expression change in gene expression array and RT-qPCR, when all CDDP-resistant TGCT cell lines were pairwise combined with all -sensitive ones. Products of the identified genes are pluripotency factors, or are involved in processes, such as cell metabolism, proliferation or migration. We propose that, after clinical validation, these genes could serve as prognostic biomarkers for early detection of CDDP response in TGCT patients.

Clinical Perspectives of ERCC1 in Bladder Cancer

ERCC1 is a key regulator of nucleotide excision repair (NER) pathway that repairs bulky DNA adducts, including intrastrand DNA adducts and interstrand crosslinks (ICLs). Overexpression of ERCC1 has been linked to increased DNA repair capacity and platinum resistance in solid tumors. Multiple single nucleotide polymorphisms (SNPs) have been detected in ERCC1 gene that may affect ERCC1 protein expression. Platinum-based treatment remains the cornerstone of urothelial cancer treatment. Given the expanding application of neoadjuvant and adjuvant chemotherapy in locally advanced bladder cancer, there is an emerging need for biomarkers that could distinguish potential responders to cisplatin treatment. Extensive research has been done regarding the prognostic and predictive role of ERCC1 gene expression and polymorphisms in bladder cancer. Moreover, novel compounds have been recently developed to target ERCC1 protein function in order to maximize sensitivity to cisplatin. We aim to review all the existing literature regarding the role of the ERCC1 gene in bladder cancer and address future perspectives for its clinical application.

Soluble Syndecan-1 Levels Are Associated with Survival in Platinum-Treated Bladder Cancer Patients

Cisplatin-containing chemotherapy represents the first-line treatment for patients with locally advanced or metastatic muscle-invasive bladder cancer. Recently, novel therapies have become available for cisplatin-ineligible or -resistant patients. Therefore, prediction of cisplatin response is required to optimize therapy decisions. Syndecan-1 (SDC1) tissue expression and serum concentration may be associated with cisplatin resistance. Thus, pre-treatment serum levels of SDC1 and its expression in chemo-naïve tissues were assessed in 121 muscle-invasive bladder cancer patients who underwent postoperative platinum-based chemotherapy. SDC1 concentrations were evaluated by ELISA in 52 baseline and 90 follow-up serum samples and tissue expressions were analyzed by immunohistochemistry in an independent cohort of 69 formalin-fixed paraffin-embedded tumor samples. Pre-treatment SDC1 serum levels were significantly higher in lymph node metastatic (p = 0.009) and female patients (p = 0.026). SDC1 tissue expression did not correlate with clinicopathological parameters. High pre-treatment SDC1 serum level and the presence of distant metastasis were independent risk factors for overall survival (Hazard ratio (HR): 1.439, 95% Confidence interval (CI): 1.003–2.065, p = 0.048; HR: 2.269, 95%CI: 1.053–4.887, p = 0.036). Our results demonstrate an independent association between high baseline serum SDC1 concentration and poor survival in platinum-treated patients. Analyzing baseline serum SDC1 levels may help to predict platinum-containing chemotherapy and could help to optimize therapeutic decision-making.

The AKT/GSK3-Mediated Slug Expression Contributes to Oxaliplatin Resistance in Colorectal Cancer via Upregulation of ERCC1

Although oxaliplatin serves as one of the first-line drugs prescribed for treating colorectal cancer (CRC), the therapeutic effect is disappointing due to drug resistance. So far, the molecular mechanisms mediating oxaliplatin resistance remain unclear. In this study, we found the chemoresistance in oxaliplatin-resistant HCT116 cells (HCT116/OXA) was mediated by the upregulation of ERCC1 expression. In addition, the acquisition of resistance induced epithelialmesenchymal transition (EMT) as well as the Slug overexpression. On the contrary, Slug silencing reversed the EMT phenotype, decreased ERCC1 expression, and ameliorated drug resistance. Further mechanistical studies revealed the enhanced Slug expression resulted from the activation of AKT/glycogen synthase kinase 3 (GSK3) signaling. Moreover, in CRC patients, coexpression of Slug and ERCC1 was observed, and increased Slug expression was significantly correlated with clinicopathological factors and prognosis. Taken together, the simultaneous inhibition of the AKT/GSK3/Slug axis may be of significance for surmounting metastasis and chemoresistance, thereby improving the therapeutic outcome of oxaliplatin.

Moving towards Personalized Medicine in Muscle-Invasive Bladder Cancer: Where Are We Now and Where Are We Going?

Neoadjuvant cisplatin-based chemotherapy followed by radical cystectomy is the recommended treatment, with the highest level of evidence, for patients with muscle-invasive bladder cancer (MIBC). However, only a minority of patients receive this treatment, mainly due to patient comorbidities, the relatively small survival benefit, and the lack of predictive biomarkers to select those patients most likely to benefit from this multimodal approach. In addition, adjuvant chemotherapy has been recommended for patients with high-risk MIBC, although randomized trials have not provided conclusive evidence on the impact of this approach. At present, however, this situation is changing, largely due to our improved knowledge of the molecular biology of bladder cancer, which has enabled us to identify new prognostic and predictive biomarkers that can be used to select the most appropriate treatment for each patient. Moreover, new active treatments, especially immunotherapy, have shown promising results in the neoadjuvant setting. In addition, the gene expression profile of bladder tumors can be used to classify them into different subtypes, which correlate with specific clinical-pathological characteristics and with treatment response or resistance. Therefore, the main objective for the near future is to introduce these translational breakthroughs into routine clinical practice in order to personalize treatment for each patient.

Application of pharmacogenetics in oncology

The term "pharmacogenetics" is used to describe the study of variability in drug response due to heredity. It is associated with "gene - drug interactions". Later on, the term "pharmacogenomics" has been introduced and it comprises all genes in the genome that can define drug response. The application of pharmacogenetics in oncology is of a great significance because of the narrow therapeutic index of chemotherapeutic drugs and the risk for life-threatening adverse effects. Many cancer genomics studies have been focused on the acquired, somatic mutations; however, increasing evidence shows that inherited germline genetic variations play a key role in cancer risk and treatment outcome. The aim of this review is to summarize the state of pharmacogenomics in oncology, focusing only on germline mutations. Genetic polymorphisms can be found in the genes that code for the metabolic enzymes and cellular targets for most of the chemotherapy drugs. Nevertheless, predicting treatment outcome is still not possible for the majority of regimens. In this review, we discuss the most comprehensively studied drug-gene pairs - present knowledge and current limitations. However, further studies in larger groups of cancer patients are necessary to be conducted with precise validation of pharmacogenetic biomarkers before these markers could be routinely applied in clinical diagnosis and treatment.

Tonicity-responsive enhancer-binding protein promotes stemness of liver cancer and cisplatin resistance

BACKGROUND

High recurrence and chemoresistance drive the high mortality in hepatocellular carcinoma (HCC). Although cancer stem cells are considered to be the source of recurrent and chemoresistant tumors, they remain poorly defined in HCC. Tonicity-responsive enhancer binding protein (TonEBP) is elevated in almost all HCC tumors and associated with recurrence and death. We aimed to identify function of TonEBP in stemness and chemoresistance of liver cancer.

METHODS

Tumors obtained from 280 HCC patients were analyzed by immunohistochemical analyses. Stemness and chemoresistance of liver CSCs (LCSCs) were investigated using cell culture. Tumor-initiating activity was measured by implanting LCSCs into BALB/c nude mice.

FINDINGS

Expression of TonEBP is higher in LCSCs in HCC cell lines and correlated with markers of LCSCs whose expression is significantly associated with poor prognosis of HCC patients. TonEBP mediates ATM-mediated activation of NF-κB, which stimulates the promoter of a key stem cell transcription factor SOX2. As expected, TonEBP is required for the tumorigenesis and self-renewal of LSCSs. Cisplatin induces the recruitment of the ERCC1/XPF dimer to the chromatin in a TonEBP-dependent manner leading to DNA repair and cisplatin resistance. The cisplatin-induced inflammation in LSCSs is also dependent on the TonEBP-ERCC1/XPF complex, and leads to enhanced stemness via the ATM-NF-κB-SOX2 pathway. In HCC patients, tumor expression of ERCC1/XPF predicts recurrence and death in a TonEBP-dependent manner.

INTERPRETATION

TonEBP promotes stemness and cisplatin resistance of HCC via ATM-NF-κB. TonEBP is a key regulator of LCSCs and a promising therapeutic target for HCC and its recurrence.

Emerging biomarkers in urothelial carcinoma: Challenges and opportunities

Advanced urothelial carcinoma (UC) is a very important cause of cancer-related morbidity and mortality with, until recently, only a few available therapeutic options. The treatment landscape has dramatically changed in recent years with the introduction of immune checkpoint inhibitors and the development of novel targeted agents, such as erdafitinib, and antibody-drug conjugates, such as enfortumab vedotin. Cost-effective utilization of this rapidly expanding therapeutic armamentarium can be further optimized via the identification and validation of reliable prognostic and predictive biomarkers that inform prognostication and patient selection. In this review, we aim to summarize examples of recent developments in the rapidly expanding field of emerging biomarkers in UC, outlining challenges and opportunities.

Predictive Value of ERCC1, ERCC2, and XRCC Expression for Patients with Locally Advanced or Metastatic Gastric Cancer Treated with Neoadjuvant mFOLFOX-4 Chemotherapy

The dismal outcome in patients with locally advanced or metastatic gastric cancer (GC) highlights the need for effective systemic neoadjuvant chemotherapy to improve clinical results. This study evaluated the correlation between the expression of three DNA repair genes, namely the excision repair cross-complementing group 1 (ERCC1), excision repair cross-complementing group 2 (ERCC2), and X-ray repair cross-complementing protein 1 (XRCC1) and the clinical outcome of patients with locally advanced or metastatic GC treated with mFOLFOX-4 neoadjuvant chemotherapy. Fifty-eight patients with histologically confirmed locally advanced or metastatic GC following neoadjuvant mFOLFOX-4 chemotherapy were enrolled between January 2009 and January 2018. We analyzed clinicopathological features and ERCC1, ERCC2, and XRCC1 expression to identify potential predictors of clinical response. Among the 58 patients, 16 (27.6%) were categorized into the response group (partial response) and 42 into the nonresponse group (stable disease in 24 patients and progressive disease in 18 patients). A multivariate analysis showed that ERCC1 overexpression (P = 0.003), ERCC2 overexpression (P = 0.049), and either ERCC1 or ERCC2 overexpression (P = 0.002) were independent predictors of response following mFOLFOX-4 neoadjuvant chemotherapy. Additionally, ERCC1 and ERCC2 overexpression did not only predict the response but also progression-free survival (both P < 0.05) and overall survival (both P < 0.05). ERCC1 and ERCC2 overexpression are promising predictive biomarkers for patients with locally advanced or metastatic GC receiving neoadjuvant mFOLFOX-4 chemotherapy and the potential clinical implication is mandatory for further investigation.

Role of common ERCC1 polymorphisms in cisplatin-resistant epithelial ovarian cancer patients: A study in Chinese cohort

Epithelial ovarian cancer (EOC) contributes the majority of death cases among various ovarian malignancies. Although a standard method of treatment is the surgical removal of malignant tissue followed by platinum-based chemotherapy, a group of patients does not respond appropriately to cisplatin. An appropriate response to cisplatin has been linked with the nucleotide excision repair mechanism. The present study aims to investigate the role of polymorphisms in DNA repair genes, excision repair cross-complementation group 1 (ERCC1) with susceptibility to EOC development and tumour response to platinum-based chemotherapy in Chinese EOC patients. Patients (n = 559) reporting to the Department of Oncology and general surgery, the First Affiliated Hospital of Kunming Medical University, were enrolled in the study. Three hundred twenty-three healthy controls hailing from similar geographical areas without a history of cancer enrolled as healthy controls. Excision repair cross-complementation group 1 polymorphisms (rs11615, rs3212986, rs735482, rs2336219, rs3212980, rs3212964, rs3212961 and rs2298881) were genotyped by appropriate methods. Distribution of genotypes and allele for ERCC1 polymorphisms (rs11615, rs3212986, rs735482, rs2336219, rs3212980, rs3212964, rs3212961 and rs2298881) were comparable among healthy controls and EOC patients. Interestingly, homozygous mutant and the minor allele for rs11615 and rs3212986 polymorphisms were significantly higher in nonresponder EOC patients when compared to those with a proper response to cisplatin treatment. The prevalence of other SNPs was comparable among the two treated clinical categories. Furthermore, combined genotype revealed significant association of rs11615: TT/ rs3212986: AA genotype combination with cisplatin nonresponder. Variants of rs11615, rs3212986 polymorphisms are associated with cisplatin resistance in Chinese EOC patients. Combined rs11615 and rs3212986 genotypes can be used as a predictive biomarker for platinum-based chemotherapy outcomes.

Links between cancer metabolism and cisplatin resistance

Cisplatin is one of the most potent and widely used chemotherapeutic agent in the treatment of several solid tumors, despite the high toxicity and the frequent relapse of patients due to the onset of drug resistance. Resistance to chemotherapeutic agents, either intrinsic or acquired, is currently one of the major problems in oncology. Thus, understanding the biology of chemoresistance is fundamental in order to overcome this challenge and to improve the survival rate of patients. Studies over the last 30 decades have underlined how resistance is a multifactorial phenomenon not yet completely understood. Recently, tumor metabolism has gained a lot of interest in the context of chemoresistance; accumulating evidence suggests that the rearrangements of the principal metabolic pathways within cells, contributes to the sensitivity of tumor to the drug treatment. In this review, the principal metabolic alterations associated with cisplatin resistance are highlighted. Improving the knowledge of the influence of metabolism on cisplatin response is fundamental to identify new possible metabolic targets useful for combinatory treatments, in order to overcome cisplatin resistance.

Targeting DNA repair in cancer: current state and novel approaches

DNA damage response, DNA repair and genomic instability have been under study for their role in tumor initiation and progression for many years now. More recently, next-generation sequencing on cancer tissue from various patient cohorts have revealed mutations and epigenetic silencing of various genes encoding proteins with roles in these processes. These findings, together with the unequivocal role of DNA repair in therapeutic response, have fueled efforts toward the clinical exploitation of research findings. The successful example of PARP1/2 inhibitors has also supported these efforts and led to numerous preclinical and clinical trials with a large number of small molecules targeting various components involved in DNA repair singularly or in combination with other therapies. In this review, we focus on recent considerations related to DNA damage response and new DNA repair inhibition agents. We then discuss how immunotherapy can collaborate with these new drugs and how epigenetic drugs can rewire the activity of repair pathways and sensitize cancer cells to DNA repair inhibition therapies.

Predictive Value of Excision Repair Cross-Complementation Group 1 in the Response to Platinum-Based Chemotherapy in Esophageal Cancer: A Meta-Analysis

INTRODUCTION

Platinum is widely used in the treatment of esophageal cancer. In clinical practice, it is significant to distinguish patients who respond to platinum from those who do not. Excision repair cross-complementation group 1 (ERCC1) is thought to be the key in the resistance to platinum. However, whether it is related to the platinum-based chemotherapy response on real esophageal cancer patients is controversial. We conducted this meta-analysis to explore the association between ERCC1 polymorphisms, its expression levels and platinum-based chemotherapy response, and identify the most sensitive genotypes.

METHODS

The study was carried out according to the Cochrane handbook for systemic reviews of intervention. The study protocol has been registered on PROSPERO.

RESULTS

Three studies were included in the analysis of C8092A polymorphisms, 5 in the C118T, and another 6 in ERCC1 expression levels. In C118T polymorphisms, compared to wild genotype, patients with mutant genotypes had a significantly higher response rate. As for C8092A polymorphisms, the mutant genotypes also presented a better response than the wild genotype. The pooled analysis indicated a significantly higher response rate in patients with a low expression of ERCC1.

CONCLUSIONS

ERCC1 is a valuable biomarker for platinum-based chemotherapy in esophageal cancer. Patients with ERCC1 mutations or low-level ERCC1 expression are more sensitive to platinum-based chemotherapy.