Sequential intravesical mitomycin plus Bacillus Calmette-Guérin for non-muscle-invasive urothelial bladder carcinoma: translational and phase I clinical trial

Intravesical Ty21a treatment of non-muscle invasive bladder cancer induces immune responses that correlate with safety and may be associated to therapy potential

BACKGROUND

Standard of care treatment of non-muscle invasive bladder cancer (NMIBC) with intravesical Bacillus Calmette Guérin (BCG) is associated with side effects, disease recurrence/progression and supply shortages. We recently showed in a phase I trial (NCT03421236) that intravesical instillation in patients with NMIBC with the maximal tolerated dose of Ty21a/Vivotif, the oral vaccine against typhoid fever, might have a better safety profile. In the present report, we assessed the immunogenicity of intravesical Ty21a in patients of the clinical trial that had received the maximal tolerated dose and compared it with data obtained in patients that had received standard BCG.

METHODS

Urinary cytokines and immune cells of patients with NMIBC treated with intravesical instillations of Ty21a (n=13, groups A and F in NCT03421236) or with standard BCG in a concomitant observational study (n=12, UROV1) were determined by Luminex and flow cytometry, respectively. Serum anti-lipopolysaccharide Typhi antibodies and circulating Ty21a-specific T-cell responses were also determined in the Ty21a patients. Multiple comparisons of different paired variables were performed with a mixed-effect analysis, followed by Sidak post-test. Single comparisons were performed with a paired or an unpaired Student's t-test.

RESULTS

As compared with BCG, Ty21a induced lower levels of inflammatory urinary cytokines, which correlated to the milder adverse events (AEs) observed in Ty21a patients. However, both Ty21a and BCG induced a Th1 tumor environment. Peripheral Ty21a-specific T-cell responses and/or antibodies were observed in most Ty21a patients, pointing the bladder as an efficient local immune inductive site. Besides, Ty21a-mediated stimulation of unconventional Vδ2 T cells was also observed, which turned out more efficient than BCG. Finally, few Ty21a instillations were sufficient for increasing urinary infiltration of dendritic cells and T cells, which were previously associated with therapeutic efficacy in the orthotopic mouse model of NMIBC.

CONCLUSIONS

Ty21a immunotherapy of patient with NMIBC is promising with fewer inflammatory cytokines and mild AE, but induction of immune responses with possible antitumor potentials. Future phase II clinical trials are necessary to explore possible efficacy of intravesical Ty21a.

Pseudomonas aeruginosa PcrV Enhances the Nitric Oxide-Mediated Tumoricidal Activity of Tumor-Associated Macrophages via a TLR4/PI3K/AKT/mTOR-Glycolysis-Nitric Oxide Circuit

Tumor-associated macrophages (TAMs), which display a tumor-supportive M2 phenotype, are closely related to tumor growth and metastasis. The reprogramming of TAMs toward a tumoricidal M1 profile has emerged as an attractive strategy for cancer immunotherapy. In this study, we found that the intratumoral injection of PcrV protein, a component of the Pseudomonas aeruginosa type 3 secretion system, suppressed tumor growth and increased apoptosis, inducible nitric oxide synthase (iNOS) expression, and the percentage of M1-polarized TAMs in tumor tissues. Furthermore, the intratumoral injection of PcrV-primed macrophages exerted a similar tumoricidal effect. In vitro analyses revealed that PcrV reeducated TAMs toward an antitumoral M1 phenotype and augmented their nitric oxide (NO)-mediated cytotoxicity against cancer cells. Mechanistically, we found that these effects were dependent on the activation of Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)-mediated regulation of a PI3K/AKT/mTOR-glycolysis-NO feedback loop via direct interaction with TLR4. Collectively, these results revealed a potential role for PcrV in cancer immunotherapy through the targeting of TAM plasticity.

CD122-targeted interleukin-2 and αPD-L1 treat bladder cancer and melanoma via distinct mechanisms, including CD122-driven natural killer cell maturation

Bladder cancer (BC) and melanoma are amenable to immune checkpoint blockade (ICB) therapy, yet most patients with advanced/metastatic disease do not respond. CD122-targeted interleukin (IL)-2 can improve ICB efficacy, but mechanisms are unclear. We tested αPD-L1 and CD122-directed immunotherapy with IL-2/αIL-2 complexes (IL-2c) in primary and metastatic bladder and melanoma tumors. IL-2c treatment of orthotopic MB49 and MBT-2 BC generated NK cell antitumor immunity through enhanced activation, reduced exhaustion, and promotion of a mature, effector NK cell phenotype. By comparison, subcutaneous B16-F10 melanoma, which is IL-2c sensitive, requires CD8⁺ T and not NK cells, yet we found αPD-L1 efficacy requires both CD8⁺ T and NK cells. We then explored αPD-L1 and IL-2c mechanisms at distinct metastatic sites and found intraperitoneal B16-F10 metastases were sensitive to αPD-L1 and IL-2c, with IL-2c but not αPD-L1, increasing CD122⁺ mature NK cell function, confirming conserved IL-2c effects in distinct cancer types and anatomic compartments. αPD-L1 failed to control tumor growth and prolong survival in B16-F10 lung metastases, yet IL-2c treated B16-F10 lung metastases effectively even in T cell and adaptive immunity deficient mice, which was abrogated by NK cell depletion in wild-type mice. Flow cytometric analyses of NK cells in B16-F10 lung metastases suggest that IL-2c directly boosts NK cell activation and effector function. Thus, αPD-L1 and IL-2c mediate nonredundant, immune microenvironment-specific treatment mechanisms involving CD8⁺ T and NK cells in primary and metastatic BC and melanoma. Mechanistic differences suggest effective treatment combinations including in other tumors or sites, warranting further studies.

BCG immunotherapy inhibits cancer progression by promoting the M1 macrophage differentiation of THP‑1 cells via the Rb/E2F1 pathway in cervical carcinoma

Bacillus Calmette-Guérin (BCG) immunotherapy increases macrophage polarization toward M1-type macrophages. In the present study, to identify the M1/M2 marker genes in the carcinogenesis and progression of cervical cancer, the microarray datasets GSE9750 and GSE7803 were downloaded from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) and the University of California Santa Cruz (UCSC) Xena browser. Survival analysis revealed that M1 markers (IL-12) were involved in anti-tumour progression, and M2 markers (IL-10) were involved in the carcinogenesis and invasion of cervical cancer. The expression of M1 markers (IL-12, inducible nitric oxide synthase and CD80) and M2 markers (IL-10 and arginase) was examined to determine whether BCG affects the polarization of macrophages and to elucidate the underlying mechanisms. The results revealed that BCG promoted macrophage polarization towards the M1 phenotype and enhanced the transition of M2 to M1 macrophages. The results also revealed that polarized M1 macrophages induced by BCG decreased the protein expression of phosphorylated (p-)retinoblastoma (Rb)/E2F transcription factor 1 (E2F1), inhibited the proliferation and promoted the apoptosis of HeLa cells. On the whole, these results demonstrated that BCG promoted the anti-tumour progression of M1 macrophages and inhibited the pro-tumour activation of M2 macrophages via the Rb/E2F1 signalling pathway in HeLa cells. This suggests the possibility of a direct translation of this combination strategy to clinical practice for the treatment of cervical cancer.

Intravesical mitomycin C (MMC) and MMC + cytosine arabinoside for non-muscle-invasive bladder cancer: a randomised clinical trial

Objectives

To compare the urinary pH, recurrence‐free survival (RFS), and safety of adjuvant intravesical therapy in patients with non‐muscle‐invasive bladder cancer (NMIBC) receiving mitomycin C (MMC) therapy and MMC + cytosine arabinoside (Ara‐C) therapy.

Patients and Methods

A total of 165 patients with NMIBC from six hospitals were randomly allocated to two groups: weekly instillation of MMC + Ara‐C (30 mg/30 mL + 200 mg/10 mL) for 6 weeks and the same instillation schedule of MMC (30 mg/40 mL). The primary outcome was RFS, and secondary outcomes were urinary pH and toxicity in the two groups.

Results

A total of 81 and 87 patients were randomised into the MMC and MMC + Ara‐C groups, respectively. Overall, the RFS in the MMC + Ara‐C group was significantly longer (P = 0.018) than that in the MMC group. A similar significant difference was detected in patients with intermediate‐risk NMIBC, but not in those with high‐risk NMIBC. The mean (SD) urinary pH was significantly higher in the MMC + Ara‐C group than in the MMC group, at 6.56 (0.61) vs 5.78 (0.64) (P < 0.001), and the frequency of a urinary pH of >7.0 in the MMC and MMC + Ara‐C groups was 6.3% and 26.7%, respectively (P < 0.001). Multivariate analysis models including clinicopathological features and second transurethral resection demonstrated that increased urinary pH was associated with better outcomes (hazard ratio 0.18, 95% confidential interval 0.18–0.038; P < 0.001). In all, there were 14 and 10 adverse events in the MMC and MMC + Ara‐C groups, respectively, without a significant difference (P = 0.113).

Conclusions

Our randomised clinical trial suggested that intravesical therapy with MMC and Ara‐C is useful and safe for patients with intermediate‐risk NMIBC. Increase in urinary pH with Ara‐C is speculated as a mechanism for increased anti‐cancer effects.

Mitochondrial metabolic reprogramming controls the induction of immunogenic cell death and efficacy of chemotherapy in bladder cancer

Although chemotherapeutic agents have been used for decades, the mechanisms of action, mechanisms of resistance, and the best treatment schedule remain elusive. Mitomycin C (MMC) is the gold standard treatment for non-muscle-invasive bladder cancer (NMIBC). However, it is effective only in a subset of patients, suggesting that, aside from cytotoxicity, other mechanisms could be involved in mediating the success of the treatment. Here, we showed that MMC promotes immunogenic cell death (ICD) and in vivo tumor protection. MMC-induced ICD relied on metabolic reprogramming of tumor cells toward increased oxidative phosphorylation. This favored increased mitochondrial permeability leading to the cytoplasmic release of mitochondrial DNA, which activated the inflammasome for efficient IL-1β (interleukin-1β) secretion that promoted dendritic cell maturation. Resistance to ICD was associated with mitochondrial dysfunction related to low abundance of complex I of the respiratory chain. Analysis of complex I in patient tumors indicated that low abundance of this mitochondrial complex was associated with recurrence incidence after chemotherapy in patients with NMIBC. The identification of mitochondria-mediated ICD as a mechanism of action of MMC offers opportunities to optimize bladder cancer management and provides potential markers of treatment efficacy that could be used for patient stratification.

Non-muscle-invasive bladder cancer: An overview of potential new treatment options

AIM

This review article summarizes the current clinical practice guidelines around disease definitions and risk stratifications, and the treatment of non-muscle-invasive bladder cancer (NMIBC). Recently completed and ongoing clinical trials of novel and investigational therapies in Bacillus Calmette-Guérin (BCG)-naïve, BCG-recurrent, and BCG-unresponsive patient populations are also described, e.g., those involving immune checkpoint inhibitors, targeted therapies, other chemotherapy regimens, vaccines, and viral- or bacterial-based treatments. Finally, a brief overview of enhanced cystoscopy and drug delivery systems for the diagnosis and treatment of NMIBC is provided.

BACKGROUND

A global shortage of access to BCG is affecting the management of BCG-naïve and BCG-recurrent/unresponsive NMIBC; hence, there is an urgent need to assist patients and urologists to enhance the treatment of this disease.

METHODS

Searches of ClinicalTrials.gov, PubMed, and Google Scholar were conducted. Published guidance and conference proceedings from major congresses were reviewed.

CONCLUSION

Treatment strategies for NMIBC are generally consistent across guidelines. Several novel therapies have demonstrated promising antitumor activity in clinical trials, including in high-risk or BCG-unresponsive disease. The detection, diagnosis, surveillance, and treatment of NMIBC have also been improved through enhanced disease detection.

CD122-directed interleukin-2 treatment mechanisms in bladder cancer differ from αPD-L1 and include tissue-selective γδ T cell activation

BACKGROUND

Anti-programmed death-ligand 1 (αPD-L1) immunotherapy is approved to treat bladder cancer (BC) but is effective in <30% of patients. Interleukin (IL)-2/αIL-2 complexes (IL-2c) that preferentially target IL-2 receptor β (CD122) augment CD8⁺ antitumor T cells known to improve αPD-L1 efficacy. We hypothesized that the tumor microenvironment, including local immune cells in primary versus metastatic BC, differentially affects immunotherapy responses and that IL-2c effects could differ from, and thus complement αPD-L1.

METHODS

We studied mechanisms of IL-2c and αPD-L1 efficacy using PD-L1⁺ mouse BC cell lines MB49 and MBT-2 in orthotopic (bladder) and metastatic (lung) sites.

RESULTS

IL-2c reduced orthotopic tumor burden and extended survival in MB49 and MBT-2 BC models, similar to αPD-L1. Using antibody-mediated cell depletions and genetically T cell-deficient mice, we unexpectedly found that CD8⁺ T cells were not necessary for IL-2c efficacy against tumors in bladder, whereas γδ T cells, not reported to contribute to αPD-L1 efficacy, were indispensable for IL-2c efficacy there. αPD-L1 responsiveness in bladder required conventional T cells as expected, but not γδ T cells, altogether defining distinct mechanisms for IL-2c and αPD-L1 efficacy. γδ T cells did not improve IL-2c treatment of subcutaneously challenged BC or orthotopic (peritoneal) ovarian cancer, consistent with tissue-specific and/or tumor-specific γδ T cell contributions to IL-2c efficacy. IL-2c significantly altered bladder intratumoral γδ T cell content, activation status, and specific γδ T cell subsets with antitumor or protumor effector functions. Neither IL-2c nor αPD-L1 alone treated lung metastatic MB49 or MBT-2 BC, but their combination improved survival in both models. Combination treatment efficacy in lungs required CD8⁺ T cells but not γδ T cells.

CONCLUSIONS

Mechanistic insights into differential IL-2c and αPD-L1 treatment and tissue-dependent effects could help develop rational combination treatment strategies to improve treatment efficacy in distinct cancers. These studies also provide insights into γδ T cell contributions to immunotherapy in bladder and engagement of adaptive immunity by IL-2c plus αPD-L1 to treat refractory lung metastases.

Rapamycin enhances BCG-specific γδ T cells during intravesical BCG therapy for non-muscle invasive bladder cancer: a randomized, double-blind study

BACKGROUND

Although intravesical BCG is the standard treatment of high-grade non-muscle invasive bladder cancer (NMIBC), response rates remain unsatisfactory. In preclinical models, rapamycin enhances BCG vaccine efficacy against tuberculosis and the killing capacity of γδ T cells, which are critical for BCG's antitumor effects. Here, we monitored immunity, safety, and tolerability of rapamycin combined with BCG in patients with NMIBC.

METHODS

A randomized double-blind trial of oral rapamycin (0.5 or 2.0 mg daily) versus placebo for 1 month was conducted in patients with NMIBC concurrently receiving 3 weekly BCG instillations (NCT02753309). The primary outcome was induction of BCG-specific γδ T cells, measured as a percentage change from baseline. Post-BCG urinary cytokines and immune cells were examined as surrogates for local immune response in the bladder. Secondary outcomes measured were adverse events (AEs) and tolerability using validated patient-reported questionnaires.

RESULTS

Thirty-one patients were randomized (11 placebo, 8 rapamycin 2.0 mg, and 12 rapamycin 0.5 mg). AEs were similar across groups and most were grade 1-2. One (12.5%) patient randomized to 2.0 mg rapamycin was taken off treatment due to stomatitis. No significant differences in urinary symptoms, bowel function, or bother were observed between groups. The median (IQR) percentage change in BCG-specific γδ T cells from baseline per group was as follows: -26% (-51% to 24%) for placebo, 9.6% (-59% to 117%) for rapamycin 0.5 mg (versus placebo, p=0.18), and 78.8% (-31% to 115%) for rapamycin 2.0 mg (versus placebo, p=0.03). BCG-induced cytokines showed a progressive increase in IL-8 (p=0.02) and TNF-α (p=0.04) over time for patients on rapamycin 2.0 mg, whereas patients receiving placebo had no significant change in urinary cytokines. Compared with placebo, patients receiving 2.0 mg rapamycin had increased urinary γδ T cells at the first week of BCG (p=0.02).

CONCLUSIONS

Four weeks of 0.5 and 2.0 mg oral rapamycin daily is safe and tolerable in combination with BCG for patients with NMIBC. Rapamycin enhances BCG-specific γδ T cell immunity and boosts urinary cytokines during BCG treatment. Further study is needed to determine long-term rapamycin safety, tolerability and effects on BCG efficacy.

Wnt5a/CaMKII/ERK/CCL2 axis is required for tumor-associated macrophages to promote colorectal cancer progression

Tumor-associated macrophages (TAMs) are closely correlated with tumor occurrence, invasion, and metastasis. However, factors affecting the biological functions of TAMs in colorectal cancer (CRC) are incompletely understood. Here, we found that Wnt5a was mainly expressed on TAMs of tumor stroma but not on CRC cells. Subsequently, we found that Wnt5a⁺ TAMs facilitated tumor cell proliferation and migration, and recruited macrophages infiltration. Furthermore, Wnt5a knockdown impaired the pro-tumor roles of TAMs in vivo and in vitro. Mechanistically, the cancer-promoting roles of Wnt5a in TAMs depended on CaMKII-ERK pathway-mediated CCL2 secretion. Our data reveal the crucial role played by TAM-expressed Wnt5a in CRC tumorigenesis through paracrine secretion of CCL2. We first report the connection between Wnt5a/CaMKII/ERK/CCL2 axis and biological functions of TAMs in tumor microenvironment, indicating that Wnt5a may be a novel therapeutic target for CRC.

A review on the role of M2 macrophages in bladder cancer; pathophysiology and targeting

Tumor-associated macrophages (TAMs) which are often referred to as immunosuppressive cells (M2 macrophage), constitute a subset of tumor microenvironment cells and affect tumor progression in solid tumors. Recently, these cells have gained remarkable importance as therapeutic candidates for solid tumors. In bladder cancer, major studies have focused on evaluating TAMs in response to Bacillus Calmette-Guerin (BCG) therapy. M2 macrophages may directly impact the BCG-induced immune responses against tumor in bladder cancer. They are the main inhibitors of the tumor microenvironment that promotes growth and metastasis of the tumor. However, the clinical significance of M2 macrophages in bladder cancer is controversial. In this review, we will discuss the clinical significance of M2 macrophages in prognosis of bladder cancer as well as worth of their potential targeting in bladder cancer treatment. In the following, we will introduce important factors resulting in M2 macrophage promotion and also experimental therapeutic agents that may cause the inhibition of bladder cancer tumor growth.

Percutaneous BCG enhances innate effector antitumor cytotoxicity during treatment of bladder cancer: a translational clinical trial

Background: Intravesical bacillus Calmette-Guérin (BCG) is the gold standard immunologic agent for treating patients with high-grade non-muscle invasive bladder cancer (NMIBC). Nevertheless, relapse rates remain high and BCG unresponsive NMIBC often requires bladder removal. Preclinical data suggest that priming with percutaneous BCG vaccine could improve response to intravesical BCG. Methods: A single-arm trial (NCT02326168) was performed to study the safety, immunogenicity, and preliminary efficacy of priming. Percutaneous BCG was given 21 days prior to intravesical BCG instillation in patients (n = 13) with high-risk NMIBC. Immune responses were monitored and compared to a sequentially enrolled cohort of nine control patients receiving only intravesical BCG. The effect of BCG on natural killer (NK) and γδ T cell in vitro cytotoxicity was tested. γδ T cell subsets were determined by T cell receptor gene expression with NanoString. Results: Priming was well tolerated and caused no grade ≥3 adverse events. The 3-month disease-free rate for prime patients was 85% (target goal ≥ 75%). Priming boosted BCG-specific immunity at 3 months and increased the activation status of in vitro expanded circulating NK and γδ T cells and their cytotoxicity against bladder cancer cells through receptor NKG2D. BCG enhanced the cytotoxicity of NK and γδ T cells against K562, RT4, and UM-UC6 but not against T24, UM-UC-3, or UM-UC-14 cells. Infiltrating γδ T cell subsets identified in the bladder includes γ9δ2 and γ8δ2. Conclusions: BCG priming is safe and tolerable. Poor sensitivity to NK and γδ T cell cytotoxicity by some bladder tumors represents a potential BCG-resistance mechanism.

Rapamycin Prevents Surgery-Induced Immune Dysfunction in Patients with Bladder Cancer

The mechanistic target of rapamycin (mTOR) integrates environmental inputs to regulate cellular growth and metabolism in tumors. However, mTOR also regulates T-cell differentiation and activation, rendering applications of mTOR inhibitors toward treating cancer complex. Preclinical data support distinct biphasic effects of rapamycin, with higher doses directly suppressing tumor cell growth and lower doses enhancing T-cell immunity. To address the translational relevance of these findings, the effects of the mTOR complex 1 (mTORC1) inhibitor, rapamycin, on tumor and T cells were monitored in patients undergoing cystectomy for bladder cancer. MB49 syngeneic murine bladder cancer models were tested to gain mechanistic insights. Surgery-induced T-cell exhaustion in humans and mice and was associated with increased pulmonary metastasis and decreased PD-L1 antibody efficacy in mouse bladder cancer. At 3 mg orally daily, rapamycin concentrations were 2-fold higher in bladder tissues than in blood. Rapamycin significantly inhibited tumor mTORC1, shown by decreased rpS6 phosphorylation in treated versus control patients (P = 0.008). Rapamycin reduced surgery-induced T-cell exhaustion in patients, evidenced by a significant decrease in the prevalence of dysfunctional programmed death-1 (PD-1)-expressing T cells. Grade 3 to 4 adverse event rates were similar between groups, but rapamycin-treated patients had a higher rate of wound complications versus controls. In conclusion, surgery promoted bladder cancer metastasis and decreased the efficacy of postoperative bladder cancer immunotherapy. Low-dose (3 mg daily) oral rapamycin has favorable pharmacodynamic and immune modulating activity in surgical patients and has the potential to decrease surgery-induced immune dysfunction.

Anti-EGFR Indocyanine Green-Mitomycin C-Loaded Perfluorocarbon Double Nanoemulsion: A Novel Nanostructure for Targeted Photochemotherapy of Bladder Cancer Cells

The use of phototherapy as an adjuvant bladder cancer treatment has long been considered, but its application has been severely hampered due to a lack of tumor specificity, unpredicted cytotoxicity, and insufficient anticancer efficacy. In this study, we aim to manufacture anti-EGFR indocyanine green (ICG) mitomycin C (MMC) encapsulated perfluorocarbon double nanoemulsions (EIMPDNEs), and explore their photochemotherapeutic efficacy on EGFR-expressing bladder cancer cells in vitro. The EIMPDNEs were manufactured using a double emulsification technique followed by antibody conjugation on the particles’ surfaces. The EIMPDNE were 257 ± 19.4 nm in size, with a surface charge of −12.3 ± 2.33 mV. The EGFR targetability of the EIMPNDE was confirmed by its enhanced binding efficiency to T24 cells when compared with the performance of nanodroplets without EGFR conjugation (p < 0.05). In comparison with freely dissolved ICG, the EIMPDNEs with equal ICG content conferred an improved thermal stability to the encapsulated ICG, and were able to provide a comparable hyperthermia effect and significantly enhanced the production of singlet oxygen under 808 nm near infrared (NIR) exposure with an intensity of 6 W cm−2 for 5 min (p < 0.05). Based on viability analyses, our data showed that the EIMPDNEs were effective in bladder cancer cell eradication upon NIR exposure (808 nm; 6 W cm−2), and the resulting cell death rate was even higher than that caused by a five-fold higher amount of entrapped MMC alone. With the merits of improved ICG stability, EGFR binding specificity, and effective cancer cell eradication, the EIMPDNEs exhibit potential for use in EGFR-expressing bladder cancer therapy with lower chemotoxicity.

Inflammatory microenvironment in the initiation and progression of bladder cancer

Accumulating evidence suggests the idea that chronic inflammation may play a critical role in various malignancies including bladder cancer and long-term treatment with non-steroidal anti-inflammatory drugs (NSAIDs) is significantly effective in reducing certain cancer incidence and mortality. However, the molecular mechanisms leading to malignant transformation and the progression of bladder cancer in a chronically inflammatory environment remain largely unknown. In this review, we will describe the role of inflammation in the formation and development of bladder cancer and summarize the possible molecular mechanisms by which chronic inflammation regulates cell immune response, proliferation and metastasis. Understanding the novel function orchestrating inflammation and bladder cancer will hopefully provide us insights into their future clinical significance in preventing bladder carcinogenesis and progression.

Systematic Review and Cumulative Analysis of the Combination of Mitomycin C plus Bacillus Calmette-Guérin (BCG) for Non-Muscle-Invasive Bladder Cancer

This systematic review and cumulative analysis aimed to explore the efficacy and safety of the combination of intravesical mitomycin C (MMC) plus bacillus Calmette-Guerin (BCG) for non-muscle-invasive bladder cancer (NMIBC) patients. A comprehensive literature search using Pubmed, Embase, Medline, Cochrane Library, CBM, CNKI and VIP databases was performed to identify studies applying intravesical MMC plus BCG therapy on NMIBC patients up to June 2016. Summarized unadjusted odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the efficacy and safety of the combination therapy. A total of 25 studies containing 2749 NMIBC patients were included in this systematic review. Compared with BCG monotherapy, the combination therapy could significantly reduce the tumor recurrence rate (OR = 0.64, 95% CI: 0.44-0.94, P = 0.02) and cancer-specific mortality (OR = 0.54, 95% CI: 0.34-0.87, P = 0.01), without more toxicities (OR = 0.58, 95% CI: 0.17-1.94, P = 0.37). The combination therapy could also lead to significant lower tumor recurrence rate than MMC monotherapy (OR = 0.41, 95% CI: 0.24-0.69, P = 0.0009). Our study indicates that the combination of MMC plus BCG instillation is an effective and safe adjuvant treatment for NMIBC patients.

Intravesical BCG Induces CD4+ T-Cell Expansion in an Immune Competent Model of Bladder Cancer

Intravesical bacillus Calmette-Guérin (BCG) immunotherapy is the standard of care in treating non-muscle-invasive bladder cancer, yet its mechanism of action remains elusive. Both innate and adaptive immune responses have been implicated in BCG activity. Although prior research has indirectly demonstrated the importance of T cells and shown a rise in CD4⁺ T cells in bladder tissue after BCG, T-cell subpopulations have not been fully characterized. We investigated the relationship between effector and regulatory T cells in an immune competent, clinically relevant rodent model of bladder cancer. Our data demonstrate that cancer progression in the N-methyl-N-nitrosourea (MNU) rat model of bladder cancer was characterized by a decline in the CD8/FoxP3 ratio, consistent with decreased adaptive immunity. In contrast, treatment with intravesical BCG led to a large, transient rise in the CD4⁺ T-cell population in the urothelium and was both more effective and immunogenic compared with intravesical chemotherapy. Whole-transcriptome expression profiling of posttreatment intravesical CD4⁺ and CD8⁺ T cells revealed minimal differences in gene expression after BCG treatment. Together, our results suggest that although BCG induces T-cell recruitment to the bladder, the T-cell phenotype does not markedly change, implying that combining T-cell-activating agents with BCG might improve clinical activity. Cancer Immunol Res; 5(7); 594-603. ©2017 AACR.

Topical and systemic immunoreaction triggered by intravesical chemotherapy in an N-butyl-N-(4-hydroxybutyl) nitorosamine induced bladder cancer mouse model

Intravesical bacillus Calmette-Guerin (BCG) treatment is the most common therapy to prevent progression and recurrence of non-muscle invasive bladder cancer (NMIBC). Although the immunoreaction elicited by BCG treatment is well documented, those induced by intravesical treatment with chemotherapeutic agents are much less known. We investigated the immunological profiles caused by mitomycin C, gemcitabine, adriamycin and docetaxel in the N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN)-induced orthotopic bladder cancer mouse model. Ninety mice bearing orthotopic bladder cancer induced by BBN were randomly divided into six groups and treated with chemotherapeutic agents once a week for four weeks. After last treatment, bladder and serum samples were analyzed for cell surface and immunological markers (CD4, CD8, CD56, CD204, Foxp3, and PD-L1) using immunohistochemistry staining. Serum and urine cytokine levels were evaluated by ELISA. All chemotherapeutic agents presented anti-tumor properties similar to those of BCG. These included changes in immune cells that resulted in fewer M2 macrophages and regulatory T cells around tumors. This result was compatible with those in human samples. Intravesical chemotherapy also induced systemic changes in cytokines, especially urinary interleukin (IL)-17A and granulocyte colony stimulating factor (G-CSF), as well as in the distribution of blood neutrophils, lymphocytes, and monocytes. Our findings suggest that intravesical treatment with mitomycin C and adriamycin suppresses protumoral immunity while enhancing anti-tumor immunity, possibly through the action of specific cytokines. A better understanding of the immunoreaction induced by chemotherapeutic agents can lead to improved outcomes and fewer side effects in intravesical chemotherapy against NMIBC.

Efficacy of bacillus Calmette-Guérin Strains for Treatment of Nonmuscle Invasive Bladder Cancer: A Systematic Review and Network Meta-Analysis

PURPOSE

We sought to determine the efficacy of genetically distinct bacillus Calmette-Guérin strains in preventing disease recurrence in patients with nonmuscle invasive bladder cancer.

MATERIALS AND METHODS

We conducted a systematic review and network meta-analysis of trials evaluating bacillus Calmette-Guérin strains against all possible comparators (different bacillus Calmette-Guérin strains, chemotherapy and nonbacillus Calmette-Guérin biological therapies) with intravesical chemotherapy as the common comparator. MEDLINE® (http://www.ncbi.nlm.nih.gov/pubmed) served as the primary data source, with the search from inception to October 2016 for clinical trials involving patients with nonmuscle invasive bladder cancer receiving bacillus Calmette-Guérin. Primary outcome measure was bladder cancer recurrence, defined as recurrent bladder tumor of any grade or stage. Random effect network meta-analysis provided estimates for outcomes and is presented as odds ratios.

RESULTS

Across all possible comparators (65 trials, 12,246 patients, 9 strains) there were 2,177 recurrences in 5,642 treated patients (38.6%) and 2,316 recurrences in 5,441 comparators (42.6%). With chemotherapy as the common comparator (28 trials, 5,757 patients, 5 strains) Tokyo-172 (OR 0.39, 95% CI 0.16-0.93), Pasteur (OR 0.49, 95% CI 0.28-0.86) and TICE® (OR 0.61, 95% CI 0.40-0.93) strains were significantly better than chemotherapy at preventing recurrence. No bacillus Calmette-Guérin strain demonstrated significant superiority when compared to any other strain at preventing recurrence in the network meta-analysis.

CONCLUSIONS

Bacillus Calmette-Guérin strains exhibited significant differences in efficacy compared to chemotherapy. However, no definitive conclusions could be reached regarding strain superiority, and head-to-head trials are greatly needed to further understand the importance of strain selection in determining bacillus Calmette-Guérin efficacy.

Intravesical Bacillus Calmette Guerin Combined with a Cancer Vaccine Increases Local T-Cell Responses in Non-muscle-Invasive Bladder Cancer Patients

PURPOSE

Treatments with cancer vaccines may be delivered as combination therapies for better efficacy. Addition of intravesical immunostimulation with bacteria promotes vaccine-specific T cells in the bladder and tumor-regression in murine bladder cancer models. Here, we determined whether an adjuvanted cancer vaccine can be safely administered with concomitant standard intravesical Bacillus-Calmette-Guérin (BCG) therapy and how vaccine-specific immune responses may be modulated in patients with non-muscle-invasive bladder cancer (NMIBC).

EXPERIMENTAL DESIGN

In a nonrandomized phase I open-label exploratory study, 24 NMIBC patients, apportioned in three groups, received 5 injections of a subunit cancer vaccine (recMAGE-A3 protein+AS15) alone or in two combinations of intravesical BCG-instillations. Safety profiles were compared between the three treatment groups, considering single vaccine injections or BCG instillations and concomitant interventions. Immune responses in blood and urine were compared between treatment groups and upon BCG instillations.

RESULTS

The mild adverse events (AE) experienced by all the patients were similar to AE previously reported for this vaccine and standard BCG treatment. AEs were not increased by the double interventions, suggesting that BCG did not exacerbate the AE caused by the MAGE-A3 vaccine and vice-versa. All patients seroconverted after MAGE-A3 vaccination. In half of the patients, vaccine-specific T cells were induced in blood, irrespective of BCG treatment. Interestingly, such T cells were only detected in urine upon BCG-induced T-cell infiltration.

CONCLUSIONS

Cancer vaccines, including strong adjuvants, can be safely combined with intravesical BCG therapy. The increase of vaccine-specific T cells in the bladder upon BCG provides proof-of-principle evidence that cancer vaccines with local immunostimulation may be beneficial. Clin Cancer Res; 23(3); 717-25. ©2016 AACR.

NMAAP1 Expressed in BCG-Activated Macrophage Promotes M1 Macrophage Polarization

Macrophages are divided into two subpopulations: classically activated macrophages (M1) and alternatively activated macrophages (M2). BCG (Bacilli Calmette-GuC)rin) activates disabled naC/ve macrophages to M1 macrophages, which act as inflammatory, microbicidal and tumoricidal cells through cell-cell contact and/or the release of soluble factors. Various transcription factors and signaling pathways are involved in the regulation of macrophage activation and polarization. We discovered that BCG-activated macrophages (BAM) expressed a new molecule, and we named it Novel Macrophage Activated Associated Protein 1 (NMAAP1). The current study found that the overexpression of NMAAP1 in macrophages results in M1 polarization with increased expression levels of M1 genes, such as inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-N1), Interleukin 6 (IL-6), Interleukin 12 (IL-12), Monocyte chemoattractant protein-1 (MCP-1) and Interleukin-1 beta (IL-1N2), and decreased expression of some M2 genes, such as Kruppel-like factor 4 (KLF4) and suppressor of cytokine signaling 1 (SOCS1), but not other M2 genes, including arginase-1 (Arg-1), Interleukin (IL-10), transforming growth factor beta (TGF-N2) and found in inflammatory zone 1 (Fizz1). Moreover, NMAAP1 overexpression in the RAW264.7 cell line increased cytotoxicity against MCA207 tumor cells, which depends on increased inflammatory cytokines rather than cell-cell contact. NMAAP1 also substantially enhanced the phagocytic ability of macrophages, which implies that NMAAP1 promoted macrophage adhesive and clearance activities. Our results indicate that NMAAP1 is an essential molecule that modulates macrophages phenotype and plays an important role in macrophage tumoricidal functions.

Much More than M1 and M2 Macrophages, There are also CD169(+) and TCR(+) Macrophages

Monocytes are considered to be precursor cells of the mononuclear phagocytic system, and macrophages are one of the leading members of this cellular system. Macrophages play highly diverse roles in maintaining an organism's integrity by either directly participating in pathogen elimination or repairing tissue under sterile inflammatory conditions. There are different subpopulations of macrophages and each one has its own characteristics and functions. In this review, we summarize present knowledge on the polarization of macrophages that allows the generation of subpopulations called classically activated macrophages or M1 and alternative activated macrophages or M2. Furthermore, there are macrophages that their origin and characterization still remain unclear but have been involved as main players in some human pathologies. Thus, we also review three other categories of macrophages: tumor-associated macrophages, CD169(+) macrophages, and the recently named TCR(+) macrophages. Based on the literature, we provide information on the molecular characterization of these macrophage subpopulations and their specific involvement in several human pathologies such as cancer, infectious diseases, obesity, and asthma. The refined characterization of the macrophage subpopulations can be useful in designing new strategies, supplementing those already established for the treatment of diseases using macrophages as a therapeutic target.

Combination of IFNα and poly-I:C reprograms bladder cancer microenvironment for enhanced CTL attraction

BACKGROUND

BCG is a prototypal cancer immunotherapeutic factor currently approved of bladder cancer. In attempt to further enhance the effectiveness of immunotherapy of bladder cancer and, potentially, other malignancies, we evaluated the impact of BCG on local production of chemokines attracting the desirable effector CD8(+) T cells (CTLs) and undesirable myeloid-derived suppressor cell (MDSCs) and regulatory T(reg) cells, and the ability of bladder cancer tissues to attract CTLs.

METHODS

Freshly resected bladder cancer tissues were either analyzed immediately or cultured ex vivo in the absence or presence of the tested factors. The expression of chemokine genes, secretion of chemokines and their local sources in freshly harvested and ex vivo-treated tumor explants were analyzed by quantitative PCR (Taqman), ELISAs and immunofluorescence/confocal microscopy. Migration of CTLs was evaluated ex vivo, using 24-transwell plates. Spearman correlation was used for correlative analysis, while paired Students T test or Wilcoxon was used for statistical analysis of the data.

RESULTS

Bladder cancer tissues spontaneously expressed high levels of the granulocyte/MDSC-attractant CXCL8 and Treg-attractant CCL22, but only marginal levels of the CTL-attracting chemokines: CCL5, CXCL9 and CXCL10. Baseline CXCL10 showed strong correlation with local expression of CTL markers. Unexpectedly, BCG selectively induced only the undesirable chemokines, CCL22 and CXCL8, but had only marginal impact on CXCL10 production. In sharp contrast, the combination of IFNα and a TLR3 ligand, poly-I:C (but not the combinations of BCG with IFNα or BCG with poly-I:C), induced high levels of intra-tumoral production of CXCL10 and promoted CTL attraction. The combination of BCG with IFNα + poly-I:C regimen did not show additional advantage.

CONCLUSIONS

The current data indicate that suboptimal ability of BCG to reprogram cancer-associated chemokine environment may be a factor limiting its therapeutic activity. Our observations that the combination of BCG with (or replacement by) IFNα and poly-I:C allows to reprogram bladder cancer tissues for enhanced CTL entry may provide for new methods of improving the effectiveness of immunotherapy of bladder cancer, helping to extend BCG applications to its more advanced forms, and, potentially, other diseases.