Urothelial Cancer: Inflammatory Mediators and Implications for Immunotherapy

Mechanistic Insights into the Successful Development of Combination Therapy of Enfortumab Vedotin and Pembrolizumab for the Treatment of Locally Advanced or Metastatic Urothelial Cancer

Antibody-drug conjugates (ADCs) consist of an antibody backbone that recognizes and binds to a target antigen expressed on tumor cells and a small molecule chemotherapy payload that is conjugated to the antibody via a linker. ADCs are one of the most promising therapeutic modalities for the treatment of various cancers. However, many patients have developed resistance to this form of therapy. Extensive efforts have been dedicated to identifying an effective combination of ADCs with other types of anticancer therapies to potentially overcome this resistance. A recent clinical study demonstrated that a combination of the ADC enfortumab vedotin (EV) with the immune checkpoint inhibitor (ICI) pembrolizumab can achieve remarkable clinical efficacy as the first-line therapy for the treatment of locally advanced or metastatic urothelial carcinoma (la/mUC)-leading to the first approval of a combination therapy of an ADC with an ICI for the treatment of cancer patients. In this review, we highlight knowledge and understanding gained from the successful development of EV and the combination therapy of EV with ICI for the treatment of la/mUC. Using urothelial carcinoma as an example, we will focus on dissecting the underlying mechanisms necessary for the development of this type of combination therapy for a variety of cancers.

Prognostic Significance of Systemic Inflammation Markers in Testicular and Penile Cancer: A Narrative Review of Current Literature

In contemporary clinical practice, biomarkers are indispensable in the assessment and management of oncological patients. Although established serum tumor markers (beta human chorionic gonadotropin (bHCG), alpha fetoprotein (AFP), and lactate dehydrogenase (LDH)) have an indisputably important role in the management of patients with testicular cancer (TC), the application of these tumor markers may be accompanied with certain limitations, implying the need for additional biomarkers. Contrary to TC, there is a lack of established serological biomarkers for penile cancer (PC) and the management of this urological malignancy is based on multiple clinicopathological parameters. Therefore, the identification and rigorous analytical and clinical validation of reliable biomarkers are considered pivotal for improving PC management. Inflammation may be associated with all stages of oncogenesis, from initial neoplastic transformation to angiogenesis, tissue invasion, and metastasis. Accordingly, an array of inflammation-related indices have gained increasing attention as emerging predictors of oncological outcomes. The clinical usefulness of systemic inflammation markers was reported in many urological and non-urological malignancies. The aim of this narrative review is to summarize current scientific data regarding the prognostic and predictive significance of systemic inflammation markers in TC and PC patients.

Significance of tumor-associated neutrophils, lymphocytes, and neutrophil-to-lymphocyte ratio in non-invasive and invasive bladder urothelial carcinoma

Background

Tumor-infiltrating neutrophils and lymphocytes play essential roles in promoting or combating various neoplasms. This study aimed to investigate the association between tumor-infiltrating neutrophils and lymphocytes and the neutrophil-to-lymphocyte ratio in the progression of urothelial carcinoma.

Methods

A total of 106 patients diagnosed with urothelial carcinoma were was. Pathological examination for tumor grade and stage and for tumor-infiltrating neutrophils, both CD4 and CD8+ T lymphocytes, as well as the neutrophil- to-lymphocyte ratio were evaluated.

Results

The presence of neutrophils and the neutrophil-to-lymphocyte ratio correlated with high-grade urothelial neoplasms. In both low- and high-grade tumors, the lymphocytes increased during progression from a non-invasive neoplasm to an early-invasive neoplasm. CD8+ T lymphocytes increased in low-grade non-muscle-invasive tumors compared to non-invasive tumors. Additionally, there was a significant decrease in CD8+ T lymphocytes during progression to muscle-invasive tumors.

Conclusions

Our results suggest that tumor-infiltrating neutrophils and CD8+ T lymphocytes have a significant effect on tumor grade and progression.

Distinct immune and inflammatory response patterns contribute to the identification of poor prognosis and advanced clinical characters in bladder cancer patients

Due to the molecular heterogeneity, most bladder cancer (BLCA) patients show no pathological responses to immunotherapy and chemotherapy yet suffer from their toxicity. This study identified and validated three distinct and stable molecular clusters of BLCA in cross-platform databases based on personalized immune and inflammatory characteristics. H&E-stained histopathology images confirmed the distinct infiltration of immune and inflammatory cells among clusters. Cluster-A was characterized by a favorable prognosis and low immune and inflammatory infiltration but showed the highest abundance of prognosis-related favorable immune cell and inflammatory activity. Cluster-B featured the worst prognosis and high immune infiltration, but numerous unfavorable immune cells exist. Cluster-C had a favorable prognosis and the highest immune and inflammatory infiltration. Based on machine learning, a highly precise predictive model (immune and inflammatory responses signature, IIRS), including FN1, IL10, MYC, CD247, and TLR2, was developed and validated to identify the high IIRS-score group that had a poor prognosis and advanced clinical characteristics. Compared to other published models, IIRS showed the highest AUC in 5 years of overall survival (OS) and a favorable predictive value in predicting 1- and 3- year OS. Moreover, IIRS showed an excellent performance in predicting immunotherapy and chemotherapy's response. According to immunohistochemistry and qRT-PCR, IIRS genes were differentially expressed between tumor tissues with corresponding normal or adjacent tissues. Finally, immunohistochemical and H&E-stained analyses were performed on the bladder tissues of 13 BLCA patients to further demonstrate that the IIRS score is a valid substitute for IIR patterns and can contribute to identifying patients with poor clinical and histopathology characteristics. In conclusion, we established a novel IIRS depicting an IIR pattern that could independently predict OS and acts as a highly precise predictive biomarker for advanced clinical characters and the responses to immunotherapy and chemotherapy.

Interplay between Comprehensive Inflammation Indices and Redox Biomarkers in Testicular Germ-Cell Tumors

Sustained and dysregulated inflammation, concurrent tumor-induced immune suppression, and oxidative stress are profoundly involved in cancer initiation, presentation, and perpetuation. Within this prospective study, we simultaneously analyzed the preoperative indices of systemic inflammatory response and the representative byproducts of oxidative DNA, protein, and lipid damage with the aim of evaluating their clinical relevance among patients diagnosed with testicular germ-cell tumors (GCT). In the analytical cohort (n = 88, median age 34 years), neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (dNLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), and C-reactive protein (CRP) were significantly altered in patients with a higher tumor stage (p < 0.05). Highly suggestive correlations were found between NLR, dNLR, and SII and modified nucleoside 8-OHdG. CRP and albumin-to-globulin ratio (AGR) significantly correlated with thiols group level and maximal tumor dimension (p < 0.05). Based on receiver operating characteristic (ROC) curve analyses, all the evaluated pre-orchiectomy inflammation markers demonstrated strong performance in predicting metastatic disease; optimal cut-off points were determined for each indicator. Although further large-scale studies are warranted, inflammatory and redox indices may both complement the established tumor markers and standard clinicopathological prognostic variables and contribute to enhanced personalized risk-assessment among testicular GCT patients.

Combination of C-Reactive Protein and Neutrophil-to-Lymphocyte Ratio as a Novel Prognostic Index in Patients With Bladder Cancer After Radical Cystectomy

Background

Inflammation is widely considered an important hallmark of cancer and associated with poor postoperative survival. The objective of this study is to assess the significance of preoperative C-NLR, a new inflammation-based index that includes preoperative C-reactive protein (CRP) and neutrophil-to-lymphocyte ratio (NLR), on therapeutic outcomes for bladder cancer (BC) patients after radical cystectomy (RC).

Materials and Methods

BC patients who underwent RC between 2010 and 2019 were retrospectively analyzed from our medical center. The predictive effect of CRP, NLR, and C-NLR on the survival of BC patients were analyzed by the receiver operating characteristic (ROC) curves. The relationship between C-NLR and postoperative survival was investigated by Cox regression. The corresponding nomograms were built based on the Cox regression results of overall survival (OS) and disease-free survival (DFS), which were further validated by ROC curves, decision curve analysis (DCA) curves, and calibration curves.

Results

Of the 199 eligible patients, 83 (41.70%) were classified as high C-NLR group and the remaining 116 (58.30%) were classified as low C-NLR group. ROC analysis showed that C-NLR had the largest area under curve (AUC) compared to CRP and NLR. Multivariate analysis revealed that T-stage and C-NLR [high C-NLR vs. low C-NLR, hazard ratio (HR) = 2.478, 95% confidence interval (CI), 1.538–3.993, p < 0.001] were independent predictors of OS, whereas T-stage, M-stage, and C-NLR (high C-NLR vs. low C-NLR, HR = 2.817, 95% CI, 1.667–4.762, p < 0.001) were independent predictors of DFS. ROC and DCA analysis demonstrated better accuracy and discrimination of 3- and 5-year OS and DFS with C-NLR-based nomogram compared to TNM stage. The calibration curve reconfirmed the accurate predicting performance of nomograms.

Conclusion

C-NLR is a reliable predictor of long-term prognosis of BC patients after RC and will contribute to the optimization of individual therapy for BC patients.

Development of nomograms related to inflammatory biomarkers to estimate the prognosis of bladder cancer after radical cystectomy

Background

Bladder cancer is one of the most common carcinomas and it brings about huge social economic burden. There is not a reliable way to predict the prognosis of bladder patients. We develop the nomogram to predict the prognosis of bladder cancer patients.

Methods

A total of 127 bladder cancer patients after radical cystectomy were studied retrospectively. Their clinicopathological data were collected for statistical analysis.

Results

The level of albumin/globulin ratio (AGR), C-reactive protein/albumin ratio (CAR), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) associated with pathological and hematological parameters like T stage and hemoglobin. Furthermore, the AGR was associated with overall survival (OS) and CAR, NLR, and PLR were associated with both OS and progression-free survival (PFS) (P<0.05). The multivariate analysis revealed that tobacco smoking, tumor T stage, M stage, NLR, CAR, and AGR were all independent predictors for OS of patients and tobacco smoking, tumor T stage, NLR, CAR, and AGR were independent predictors for PFS of patients. In addition, AGR, CAR, and NLR, as well as, the clinicopathological parameters in the development of nomograms with a C index of 0.901 (95% CI: 0.505-1.269) for OS, and 0.807 (95% CI: 0.755-0.858) for PFS. The nomograms were able to provide a prognosis of the OS with the area under the curve (AUC) =0.86. Further, tests assessed the PFS with the AUC =0.84.

Conclusions

This study demonstrates that the nomograms of the inflammatory biomarkers were able to predict prognosis of bladder cancer patients after radical cystectomy.

The Multiple Potential Biomarkers for Predicting Immunotherapy Response-Finding the Needle in the Haystack

Immune checkpoint inhibitors (ICIs) are being increasingly utilised in a variety of advanced malignancies. Despite promising outcomes in certain patients, the majority will not derive benefit and are at risk of potentially serious immune-related adverse events (irAEs). The development of predictive biomarkers is therefore critical to personalise treatments and improve outcomes. A number of biomarkers have shown promising results, including from tumour (programmed cell death ligand 1 (PD-L1), tumour mutational burden (TMB), stimulator of interferon genes (STING) and apoptosis-associated speck-like protein containing a CARD (ASC)), from blood (peripheral blood mononuclear cells (PBMCs), circulating tumour DNA (ctDNA), exosomes, cytokines and metal chelators) and finally the microbiome.

Future Strategies Involving Immune Checkpoint Inhibitors in Advanced Urothelial Carcinoma

OPINION STATEMENT

Immune checkpoint inhibitors have importantly improved the outcome of patients with urothelial carcinoma. Different immune checkpoint inhibitors are currently approved and used in first- and second-line setting. The multiple agents currently approved in these setting make the choice sometimes difficult for clinicians. Furthermore, only a minority of patients present drastic response and long-term benefit with current immunotherapy. In this review, we describe the current use of immunotherapy in urothelial carcinoma but we also highlight the new strategies of treatment involving immune checkpoint inhibitors; we describe the place of immunotherapy with chemotherapy, targeted agents, and anti-angiogenic agents, incorporating the recent results presented at ASCO 2020. This review explores also the different action mechanisms of immune checkpoint inhibitors and the molecular rational to evaluate these agents in other strategies, such as maintenance and salvage strategies. The new advances in biomarker development are also presented.

Meta-analysis of multiple hematological biomarkers as prognostic predictors of survival in bladder cancer

BACKGROUND

Accumulating emerging studies have demonstrated that systemic inflammation can obviously affect tumor occurrence and progression. Nevertheless, the prognostic value of hematological inflammation biomarkers in bladder cancer is controversial. Thus, we conducted a meta-analysis to evaluate the key hematological biomarkers with various clinical outcomes in bladder cancer.

METHODS

We used online databases PUBMED and EMBASE to search relevant studies published prior to August 2019. After collecting the basic characteristics and prognostic data from the studies included, overall survival (OS), cancer-specific survival (CSS) and progression-free survival (PFS) were used as primary results. Subgroup analyses were performed according to ethnicity, the number of samples, survival outcomes, the value of cut-off, follow-up time and metastasis stage.

RESULTS

Thirty-three independent studies with 17,087 bladder cancer patients were added in the present analysis. The collected results showed that the increased neutrophil-to-lymphocyte ratio was associated with a poor OS (hazard ratio [HR] = 1.48, 95% confidence interval [CI]: 1.32-1.67, P < .00001), CSS (HR = 1.71, 95%CI: 1.35-2.18, P < .0001) and PFS (HR = 1.59, 95%CI: 1.38-1.83, P < .00001). Additionally, the elevated platelet-to-lymphocyte ratio was related to a poor OS (HR = 1.29, 95% CI: 1.07-1.54, P = .007), CSS (HR = 1.14, 95%CI = 0.98-1.34, P = .02) and PFS (HR = 1.2, 95%CI: 1.08-1.34, P = .0008). Moreover, a decreased lymphocyte-to-monocyte ratio was associated with a poor OS (HR = 0.77, 95% CI: 0.70-0.84, P = .001), CSS (HR = 0.76, 95%CI: 0.70-0.84). An elevated modified Glasgow prognostic score was also associated with a poor OS (HR = 2.71, 95%CI: 1.08-2.82, P = .003), CSS (HR = 1.50, 95%CI: 0.56-4.05) and PFS (HR = 1.52, 95%CI: 1.23-1.88, P = .001).

CONCLUSIONS

Our study indicated that the pretreatment hematological biomarkers (neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, and modified Glasgow prognostic score) were predicative biomarkers of prognosis in bladder cancer patients. Further research is needed to conduct further prospective and multicenter studies to confirm our findings.

Evaluating prognostic utility of preoperative Neutrophil to Lymphocyte Ratio and hsa-let-7g/c up-regulation in patients with urinary bladder cancer

BACKGROUND

Stratification and risk-evaluation of bladder cancer (BCa) patients are far-reached issues, especially for those with non muscle invasive disease. Thus, setting-up biomarkers, especially after resection of the primary tumor, is crucial. Specifically, Neutrophil to lymphocyte ratio NLR and let-7 deregulation which have been preliminarily but not consistently described to be associated to unfavorable prognosis.

OBJECTIVE

To explore the clinical value of pre-treatment Neutrophil to Lymphocyte Ratio (NLR), let-7c and let-7g's deregulation.

METHODS

Data were extracted from ninety BCa samples. Pre-treatment NLR was estimated as the absolute neutrophil count divided by the absolute lymphocyte count. Expression patterns of let-7c and let-7g were assessed by qRT-PCR. Correlation with clinical characteristics was performed by descriptive statistics.

RESULTS

Both let-7 miRs were upregulated. Interestingly, let-7g was associated to pathological stage (p= 0.001) and tumor multiplicity (p= 0.003). NLR was associated to histological grade (p= 0.005) and clinical stage (p= 0.006). They were both associated to more aggressive phenotype and their worth as potential stratification biomarkers was confirmed by ROC curve.

CONCLUSIONS

Our data demonstrated the potential clinical value of all markers, especially pretreatment NLR and let-7g. Further studies are recommended to confirm their utility in improving the clinical decision-making regarding treatment and follow-up scheduling.

Complete remission with immunotherapy: Case report of a patient with metastatic bladder cancer to the humerus

Bladder cancer is the sixth most common malignancy in the United States. Cisplatin combination regimens are first line therapy for patients with metastatic urothelial bladder cancer who are eligible candidates and no treatments have shown to improve outcome compared to chemotherapy for the past 20 years. Significant advances were made in past 2-3 years and the most significant was the introduction of checkpoints inhibitors in bladder cancer treatment. We present a patient diagnosed with metastatic urothelial carcinoma who progressed while on cisplatin/gemcitabine chemotherapy in the form of oligometastasis to the bone. He has achieved a durable complete response with atezolizumab.

Targeted therapies for advanced bladder cancer: new strategies with FGFR inhibitors

Inhibitors of fibroblast growth factor receptor (FGFR) represent an outstanding treatment approach for selected patients with urothelial cancer (UC). These agents are changing the clinical approach to a subgroup of UC, the luminal-papillary subtype, characterized by FGFR mutations, fusions, or amplification. In this review, we provide an overview of the results of recent clinical trials on FGFR tyrosine kinase inhibitors (TKIs) currently in clinical development for the treatment of UC: erdafitinib, rogaratinib, infigratinib, and the monoclonal antibody vofatamab. The Food and Drug Administration recently granted accelerated approval to erdafitinib for patients with advanced UC with alterations of FGFR2 or FGFR3 after progression on platinum-based chemotherapy. We also look at future therapeutic options of combination regimens with immune-checkpoint inhibitors as strategies for improving the antitumor effects of this class of drug, and for preventing or delaying the development of resistance.

Inflammatory Biomarkers as Predictors of Response to Immunotherapy in Urological Tumors

Immunotherapy represents the new era of cancer treatment because of its promising results in various cancer types. In urological tumors, the use of the immune-checkpoint inhibitors (ICIs) is increasingly spreading. Although not all patients and not all diseases respond equally well to immunotherapy, there is an increasing need to find predictive markers of response to ICIs. Patient- and tumor-related factors may be involved in primary and secondary resistance to immunotherapy: tumor-derived protein and cytokines, tumor mutational burden, and patient performance status and comorbidities can condition tumor response to ICIs. Recently, some of these factors have been evaluated as potential biomarkers of response, with conflicting results. To date, the expression of programmed death-ligand 1 (PD-L1) and the presence of deficient mismatch repair (dMMR) in tumor tissue are the only biomarkers capable of guiding the clinician's decision in urothelial cancer and prostate cancer, respectively. In this review, we performed a comprehensive search of the main publications on biomarkers that are predictive of response to ICIs in urological cancers. Our aim was to understand whether existing data have the potential to drive clinical decision-making in the near future.

Key Role of Obesity in Genitourinary Tumors with Emphasis on Urothelial and Prostate Cancers

Background: In human populations, a certain amount of data correlate obesity/body mass index (BMI) with urothelial cancer (UC) and prostate cancer (PCa) occurrence, however this is not fully elucidated at all stages of disease. In an attempt to shed light on uncertain areas in such field, in the present review we illustrate the main molecular mechanisms linking obesity and cancer, focusing on the correlation between obesity and tumor risk, disease progression and response to chemo- and immunotherapy in patients with UC and the predictive/prognostic role of obesity in PCa patients treated with the currently available therapeutic approaches. Methods: We did a large-scale literature search on existing scientific websites focusing on keywords "obesity", "body mass index (BMI)", "urothelial cancer", "prostate cancer", "docetaxel", "cabazitaxel", "abiraterone acetate", "enzalutamide", and "radium223". Results: Many adipocytes-induced molecules support tumor proliferation through activation of various cellular pathways. The available evidence in the postoperative setting do the role of BMI in oncological outcomes prediction still not completely clear. Likewise, in metastatic UC patients controversial results link the role of obesity/BMI with clinical outcomes of tumor response to chemotherapy. Adipose stromal cells recruitment, induced by PCa cells, from white adipose tissue to the tumor sites inducing cell invasiveness was associated with poor survival. Conflicting data, although more oriented towards a better survival outcome, resulted in obese patients treated with docetaxel. In PCa cell-lines a certain cabazitaxel chemo resistance adipose stromal cells (ASC)-mediated was demonstrated. In metastatic castration-resistant PCa patients with high BMI (>25 kg/m2) receiving abiraterone acetate there were significant worse survival outcomes, while in enzalutamide patients BMI did not affect survival outcome. In radium 223 patients higher BMI significantly correlated with favorable overall survival. Conclusions: The main focus of this review was to understand the interplay between obesity/BMI and UC/PCa. Several pathogenic cellular pathways exploring the issue are discussed, opening the way to challenging tailored treatments on the basis of BMI. Improving the knowledge of molecular connections between obesity and UC and PCa could favor the development of new therapies likely reducing chemo- and immunotherapy drug resistance.

Neutrophil-to-lymphocyte ratio independently predicts advanced pathological staging and poorer survival outcomes in testicular cancer

Purpose

An elevated neutrophil-to-lymphocyte ratio (NLR) has been associated with adverse outcomes in various malignancies. However, its role in prognosticating testicular cancer (TC) has not been validated. We aim to study the relationship between NLR and TC.

Materials and Methods

We retrospectively reviewed 160 patients with histological proven TC from January 2005 to June 2016. Youden's index was used to analyse NLR and a cut-off point of 3.0 was obtained, with statistical receiver operating characteristics of 0.755. Chi-square test, Kaplan-Meier (log rank test) and logistics regression models were used to predict NLR association with survival outcomes.

Results

Median age was 34 years old (range, 17-68 years old). There were 102 pure seminomas and 58 non-seminomatous germ cell tumours. Median follow-up period was 8 years (range, 2.5-17 years). NLR ≥3.0 was independently associated with lymph node involvement (p=0.031; odds ratio [OR], 2.91; 95% confidence interval [CI], 1.67-5.83; p=0.038; OR, 4.12; 95% CI, 1.26-6.51) and metastatic disease (p=0.041; OR, 2.48; 95% CI, 1.22-3.98; p=0.043; OR, 2.21; 95% CI, 1.17-3.65) in both seminomatous and non-seminomatous germ cell tumours, translating to a more advanced disease. Moreover, NLR ≥3.0 also predicts poorer cancer specific survival in these patients.

Conclusions

NLR can be an inexpensive haematological marker in predicting advanced TC staging and poorer survival outcome. NLR complements the traditional cancer staging by identifying a group of high risk patients who may benefit from multimodal treatment and closer surveillance to achieve long term survival.

Immunotherapy for Prostate Cancer: Where We Are Headed

Prostate cancer is one of the most common malignant neoplasms in men worldwide, and is the fifth cause of cancer-related death. In recent years, a new generation of therapies have been approved for the management of metastatic disease. Moreover, the development of new immunotherapeutic drugs has become a novel frontier for the treatment of several tumor types; to date, numerous studies have investigated their potential activity, including in prostate cancer. In this article, we discuss the role of emerging immunotherapeutic drugs in prostate cancer patients.

Capsaicin Suppresses Cell Proliferation, Induces Cell Cycle Arrest and ROS Production in Bladder Cancer Cells through FOXO3a-Mediated Pathways

Capsaicin (CAP), a highly selective agonist for transient receptor potential vanilloid type 1 (TRPV1), has been widely reported to exhibit anti-oxidant, anti-inflammation and anticancer activities. Currently, several therapeutic approaches for bladder cancer (BCa) are available, but accompanied by unfavorable outcomes. Previous studies reported a potential clinical effect of CAP to prevent BCa tumorigenesis. However, its underlying molecular mechanism still remains unknown. Our transcriptome analysis suggested a close link among calcium signaling pathway, cell cycle regulation, ROS metabolism and FOXO signaling pathway in BCa. In this study, several experiments were performed to investigate the effects of CAP on BCa cells (5637 and T24) and NOD/SCID mice. Our results showed that CAP could suppress BCa tumorigenesis by inhibiting its proliferation both in vitro and in vivo. Moreover, CAP induced cell cycle arrest at G0/G1 phase and ROS production. Importantly, our studies revealed a strong increase of FOXO3a after treatment with CAP. Furthermore, we observed no significant alteration of apoptosis by CAP, whereas Catalase and SOD2 were considerably upregulated, which could clear ROS and protect against cell death. Thus, our results suggested that CAP could inhibit viability and tumorigenesis of BCa possibly via FOXO3a-mediated pathways.

Vitamin K2 Induces Mitochondria-Related Apoptosis in Human Bladder Cancer Cells via ROS and JNK/p38 MAPK Signal Pathways

The effects of vitamin K2 on apoptosis in a variety of cancer cells have been well established in previous studies. However, the apoptotic effect of vitamin K2 on bladder cancer cells has not been evaluated. The aim of this study is to examine the apoptotic activity of Vitamin K2 in bladder cancer cells and investigate the underlying mechanism. In this study, Vitamin K2 induced apoptosis in bladder cancer cells through mitochondria pathway including loss of mitochondria membrane potential, cytochrome C release and caspase-3 cascade. Furthermore, the phosphorylation of c-Jun N-terminal kinase (JNK) and p38 MAPK was detected in Vitamin K2-treated cells and both SP600125 (an inhibitor of JNK) and SB203580 (an inhibitor of p38 MAPK) completely abolished the Vitamin K2-induced apoptosis and loss of mitochondria membrane potential. Moreover, the generation of reactive oxygen species (ROS) was detected in bladder cancer cells, upon treatment of vitamin K2 and the anti-oxidant N-acetyl cysteine (NAC) almost blocked the Vitamin K2-triggered apoptosis, loss of mitochondria membrane potential and activation of JNK and p38 MAPK. Taken together, these findings revealed that Vitamin K2 induces apoptosis in bladder cancer cells via ROS-mediated JNK/p38 MAPK and Mitochondrial pathways.