Localization and expression of inducible nitric oxide synthase in patients after BCG treatment for bladder cancer

Gasotransmitters in the tumor microenvironment: Impacts on cancer chemotherapy (Review)

Nitric oxide, carbon monoxide and hydrogen sulfide are three endogenous gasotransmitters that serve a role in regulating normal and pathological cellular activities. They can stimulate or inhibit cancer cell proliferation and invasion, as well as interfere with cancer cell responses to drug treatments. Understanding the molecular pathways governing the interactions between these gases and the tumor microenvironment can be utilized for the identification of a novel technique to disrupt cancer cell interactions and may contribute to the conception of effective and safe cancer therapy strategies. The present review discusses the effects of these gases in modulating the action of chemotherapies, as well as prospective pharmacological and therapeutic interfering approaches. A deeper knowledge of the mechanisms that underpin the cellular and pharmacological effects, as well as interactions, of each of the three gases could pave the way for therapeutic treatments and translational research.

Bladder Cancer Invasion Is Mediated by Mammalian Target of Rapamycin Complex 2-Driven Regulation of Nitric Oxide and Invadopodia Formation

Bladder cancer invasion depends on mammalian target of rapamycin complex 2 (mTORC2) activity, although the downstream mTORC2 effectors that mediate this effect have not been fully defined. One potential downstream effector is the arginine derivative nitric oxide (NO). We identified a stage-associated increase in the expression of the NO-generating enzymes endothelial NO synthase (NOS) and inducible NOS (iNOS) in human bladder cancer. Reduction of NOS activity by pharmacologic inhibition or silencing of NOS enzymes reduced cancer cell invasion, with similar effects observed using the NO scavenger cobinamide. By contrast, enhanced invasion was seen with the NO donor Deta-NONOate and an analog of the downstream NO second messenger cGMP. We next evaluated NOS expression in invadopodia, which are cellular protrusions that form the invasive tips of cancer cells. Invadopodia were enriched in both iNOS protein and mTORC2 activity, and invadopodia formation was increased by Deta-NONOate and decreased by cobinamide and ablation of mTORC2 activity. mTORC2 additionally increased expression of iNOS. Using a zebrafish model, injection of iNOS- or rictor-silenced cells reduced the frequency of bladder cancer cell metastasis in zebrafish. These results indicate that mTORC2 can mediate bladder cancer cell invasion through increased iNOS expression, resulting in increased NO and cGMP production in invadopodia and further propagation of invadopodia formation.

Reactive nitrogen species in host-bacterial interactions

Reactive nitrogen species play diverse and essential roles in host-pathogen interactions. Here, we review selected recent discoveries regarding nitric oxide (NO) in host defense and the pathogenesis of infection, mechanisms of bacterial NO resistance, production of NO by human macrophages, NO-based antimicrobial therapeutics and NO interactions with the gut microbiota.

Host-Derived Nitric Oxide and Its Antibacterial Effects in the Urinary Tract

Urinary tract infection (UTI) is one of the most common bacterial infections in humans, and the majority are caused by uropathogenic Escherichia coli (UPEC). The rising antibiotic resistance among UPEC and the frequent failure of antibiotics to effectively treat recurrent UTI and catheter-associated UTI motivate research on alternative ways of managing UTI. Abundant evidence indicates that the toxic radical nitric oxide (NO), formed by activation of the inducible nitric oxide synthase, plays an important role in host defence to bacterial infections, including UTI. The major source of NO production during UTI is from inflammatory cells, especially neutrophils, and from the uroepithelial cells that are known to orchestrate the innate immune response during UTI. NO and reactive nitrogen species have a wide range of antibacterial targets, including DNA, heme proteins, iron-sulfur clusters, and protein thiol groups. However, UPEC have acquired a variety of defence mechanisms for protection against NO, such as the NO-detoxifying enzyme flavohemoglobin and the NO-tolerant cytochrome bd-I respiratory oxidase. The cytotoxicity of NO-derived intermediates is nonspecific and may be detrimental to host cells, and a balanced NO production is crucial to maintain the tissue integrity of the urinary tract. In this review, we will give an overview of how NO production from host cells in the urinary tract is activated and regulated, the effect of NO on UPEC growth and colonization, and the ability of UPEC to protect themselves against NO. We also discuss the attempts that have been made to develop NO-based therapeutics for UTI treatment.

Effects of intravesical therapy with platelet-rich plasma (PRP) and Bacillus Calmette-Guérin (BCG) in non-muscle invasive bladder cancer

This study describes the effects of a promising therapeutic alternative for non-muscle invasive bladder cancer (NMIBC) based on Bacillus Calmette-Guerin (BCG) intravesical immunotherapy combined with Platelet-rich plasma (PRP) in an animal model. Furthermore, this study describes the possible mechanisms of this therapeutic combination involving Toll-like Receptors (TLRs) 2 and 4 signaling pathways. NMIBC was induced by treating female Fischer 344 rats with N-methyl-N-nitrosourea (MNU). After treatment with MNU, the animals were distributed into four experimental groups: Control (without MNU) group, MNU (cancer) group, MNU + PRP group, MNU + BCG group and MNU + PRP + BCG group. Our results demonstrated that PRP treatment alone or associated with BCG triggered significant cytotoxicity in bladder carcinoma cells (HTB-9). Animals treated with PRP associated to BCG clearly showed better histopathological recovery from the cancer state and decrease of urothelial neoplastic lesions progression in 70% of animals when compared to groups that received the same therapies administered singly. In addition, this therapeutic association led to distinct activation of immune system TLRs 2 and 4-mediated, resulting in increased MyD88, TRIF, IRF3, IFN-γ immunoreactivities. Taken together, the data obtained suggest that interferon signaling pathway activation by PRP treatment in combination with BCG immunotherapy may provide novel therapeutic approaches for non-muscle invasive bladder cancer.

Increased toll-like receptors and p53 levels regulate apoptosis and angiogenesis in non-muscle invasive bladder cancer: mechanism of action of P-MAPA biological response modifier

BACKGROUND

The new modalities for treating patients with non-muscle invasive bladder cancer (NMIBC) for whom BCG (Bacillus Calmette-Guerin) has failed or is contraindicated are recently increasing due to the development of new drugs. Although agents like mitomycin C and BCG are routinely used, there is a need for more potent and/or less-toxic agents. In this scenario, a new perspective is represented by P-MAPA (Protein Aggregate Magnesium-Ammonium Phospholinoleate-Palmitoleate Anhydride), developed by Farmabrasilis (non-profit research network). This study detailed and characterized the mechanisms of action of P-MAPA based on activation of mediators of Toll-like Receptors (TLRs) 2 and 4 signaling pathways and p53 in regulating angiogenesis and apoptosis in an animal model of NMIBC, as well as, compared these mechanisms with BCG treatment.

RESULTS

Our results demonstrated the activation of the immune system by BCG (MyD88-dependent pathway) resulted in increased inflammatory cytokines. However, P-MAPA intravesical immunotherapy led to distinct activation of TLRs 2 and 4-mediated innate immune system, resulting in increased interferons signaling pathway (TRIF-dependent pathway), which was more effective in the NMIBC treatment. Interferon signaling pathway activation induced by P-MAPA led to increase of iNOS protein levels, resulting in apoptosis and histopathological recovery. Additionally, P-MAPA immunotherapy increased wild-type p53 protein levels. The increased wild-type p53 protein levels were fundamental to NO-induced apoptosis and the up-regulation of BAX. Furthermore, interferon signaling pathway induction and increased p53 protein levels by P-MAPA led to important antitumor effects, not only suppressing abnormal cell proliferation, but also by preventing continuous expansion of tumor mass through suppression of angiogenesis, which was characterized by decreased VEGF and increased endostatin protein levels.

CONCLUSIONS

Thus, P-MAPA immunotherapy could be considered an important therapeutic strategy for NMIBC, as well as, opens a new perspective for treatment of patients that are refractory or resistant to BCG intravesical therapy.

Treatment of non-muscle invasive bladder cancer with Bacillus Calmette-Guerin (BCG): Biological markers and simulation studies

Intravesical Bacillus Calmette-Guerin (BCG) vaccine is the preferred first line treatment for non-muscle invasive bladder carcinoma (NMIBC) in order to prevent recurrence and progression of cancer. There is ongoing need for the rational selection of i) BCG dose, ii) frequency of BCG administration along with iii) synergistic adjuvant therapy and iv) a reliable set of biochemical markers relevant to tumor response. In this review we evaluate cellular and molecular markers pertinent to the immunological response triggered by the BCG instillation and respective mathematical models of the treatment. Specific examples of markers include diverse immune cells, genetic polymorphisms, miRNAs, epigenetics, immunohistochemistry and molecular biology 'beacons' as exemplified by cell surface proteins, cytokines, signaling proteins and enzymes. We identified tumor associated macrophages (TAMs), human leukocyte antigen (HLA) class I, a combination of Ki-67/CK20, IL-2, IL-8 and IL-6/IL-10 ratio as the most promising markers for both pre-BCG and post-BCG treatment suitable for the simulation studies. The intricate and patient-specific nature of these data warrants the use of powerful multi-parametral mathematical methods in combination with molecular/cellular biology insight and clinical input.

Inflammation characteristics in bladder pain syndrome ESSIC type 3C/classic interstitial cystitis

OBJECTIVES

Interstitial cystitis is regarded as a heterogenous syndrome with two distinguishable forms: the non-ulcer and the classic form of interstitial cystitis, the latter with Hunner's lesions; or bladder pain syndrome type 3C and non-Hunner bladder pain syndrome, respectively.

METHODS

A cohort of 379 patients diagnosed with interstitial cystitis was studied. Nitric oxide release from the bladder was measured using a chemiluminescence nitric oxide analyzer. Bladder biopsies from the patients and healthy controls were analyzed by routine histopathological examination. Biopsies from a subset of patients and controls were also analyzed by immunohistochemistry and cytokine gene expression by real-time polymerase chain reaction.

RESULTS

Patients with bladder pain syndrome type 3C/classic interstitial cystitis had considerably higher levels of nitric oxide as compared with non-Hunner bladder pain syndrome/non-ulcer interstitial cystitis patients and healthy individuals, and showed histologically a chronic inflammation in the bladder mucosa, with abundant mast cell infiltration in all layers of the bladder wall. No inflammation was noted in non-Hunner bladder pain syndrome/non-ulcer interstitial cystitis patients. The isoenzymes inducible nitric oxide synthase, the catalyst in the nitric oxide production, was strongly expressed in the inflammatory cells in the bladder mucosa of bladder pain syndrome type 3C/classic interstitial cystitis patients. In addition, the expression of the pro-inflammatory cytokines interleukin-6 and interleukin-17A messenger ribonucleic acid, and of anti-inflammatory interleukin-10 messenger ribonucleic acid showed significantly increased levels in bladder pain syndrome type 3C/classic interstitial cystitis compared with healthy controls.

CONCLUSION

Bladder pain syndrome type 3C/classic interstitial cystitis is a distinct inflammatory disease and in many aspects shares features of inflammatory autoimmune diseases. These findings could open up novel research avenues with expectations for new targets for pharmacological treatment.

Exploration of risk factors predicting outcomes for primary T1 high-grade bladder cancer and validation of the Spanish Urological Club for Oncological Treatment scoring model: Long-term follow-up experience at a single institute

OBJECTIVE

To determine the prognostic factors of primary T1 high-grade bladder cancer and to validate the Spanish Urological Club for Oncological Treatment model in Japanese patients with T1 high-grade bladder cancer treated at a single institution.

METHODS

Records of 106 patients with T1 high-grade bladder cancer treated from 1998 to 2013 were retrospectively reviewed. Variables included various clinicopathological parameters, including lymphovascular invasion and tumor growth pattern at the invasion front. Recurrence-free survival and progression-free survival were analyzed. Multivariate Cox proportional regression analysis was used to verify the prognostic significance of the variables. Scores for recurrence and progression were calculated using the Spanish Urological Club for Oncological Treatment model.

RESULTS

Of 106 patients, 44 (42%) had recurrence and 16 (15%) developed progression after a median (interquartile range) follow-up period of 54 months (range 32-81 months). Non-papillary shape was the only independent predictor for recurrence, while broad-based tumor stalk and infiltrative tumor growth pattern at the invasion front were determined to be independent predictors for progression. Stratification of patients according to the number of progression risk factors yielded hazard ratios of 10.1 and 13.1 in patients having one and two risks, respectively, compared with those without any risks. The Spanish Urological Club for Oncological Treatment model successfully stratified our patients with a trend toward different probabilities of recurrence and progression.

CONCLUSIONS

The results of the present study might be helpful for counseling certain patients towards intensive treatment, such as radical cystectomy and/or platinum-based systemic chemotherapy. In addition, the Spanish Urological Club for Oncological Treatment model might be applicable to Japanese patients with T1 high-grade bladder cancer.

Can intravesical bacillus Calmette-Guérin reduce recurrence in patients with non-muscle invasive bladder cancer? An update and cumulative meta-analysis

Approximately 70% of newly diagnosed bladder tumors are non-muscle invasive bladder cancer (NMIBC). NMIBC accounts for approximately 80% of total bladder cancer cases. Bacillus Calmette-Guérin (BCG) instillation and maintenance is considered as the standard adjuvant treatment for superficial bladder cancer. A number of randomized studies have focused on the benefit of maintenance therapy following initial BCG induction. To provide further insights into the effect of intravesical instillation on recurrence in patients with NMIBC, we analyzed this relationship by conducting an updated detailed meta-analysis. Evidence suggested that adjuvant intravesical BCG with maintenance treatment is significantly effective for the prophylaxis of tumor recurrence in patients with NMIBC.

Secondary stimulation from Bacillus Calmette-Guérin induced macrophages induce nitric oxide independent cell-death in bladder cancer cells

The anti-tumour mechanisms following Bacillus Calmette-Guérin (BCG) treatment of bladder-cancer remain largely unknown. Previous studies have shown involvement of nitric-oxide (NO) formation in the BCG-mediated effect. We analyzed the effects of macrophage secreted factors (MSFs) from BCG-stimulated RAW264.7 cells on the bladder-cancer cell line MBT2. Direct treatment with BCG did not induce NO in MBT2-cells whereas supernatant from BCG-stimulated macrophages increased NOS2 mRNA and protein expression, NO concentrations and cell-death. Blocking NO-synthesis with the NOS-inhibitor L-NAME did not affect levels of cell-death suggesting cytotoxic pathways involving other signalling molecules than NO. Several such candidate genes were identified in a microarray.

Predicting recurrence and progression in Chinese patients with nonmuscle-invasive bladder cancer using EORTC and CUETO scoring models

OBJECTIVE

To validate the European Organization for Research and Treatment of Cancer (EORTC) model and the Spanish Urological Club for Oncological Treatment (CUETO) model in Chinese patients with nonmuscle-invasive bladder cancer (NMIBC).

MATERIALS AND METHODS

A retrospective study was performed of 363 Chinese patients with NMIBC treated at our hospital from January 2003 to September 2010. Most of these patients had undergone intravesical chemotherapy after transurethral resection of the bladder tumor. The scores for recurrence and progression were calculated using the 2 models. Next, all the patients were divided into 4 risk groups according to their scores. The Kaplan-Meier method was used to estimate the probabilities of recurrence and progression according to both models. Discrimination was assessed using the concordance index.

RESULTS

The EORTC model successfully stratified our patients into 4 groups with statistically significant different probabilities of recurrence. For progression, only the intermediate- and high-risk groups could be reasonably distinguished using the EORTC model. The CUETO model stratified neither the recurrence nor the progression risks. The concordance index using the EORTC and CUETO model was 0.711 and 0.663 for recurrence and 0.768 and 0.741 for progression, respectively.

CONCLUSION

Compared with the CUETO risk tables, the EORTC model showed more value in predicting recurrence and progression in Chinese patients with NMIBC, most of whom received intravesical chemotherapy after transurethral resection of the bladder tumor. Prospective multicenter studies should be performed of large cohorts to construct an ideal prognostic model for Chinese patients with NMIBC.