Current treatments for BCG failure in non-muscle invasive bladder cancer (NMIBC)

Nano-Bacillus Calmette-Guérin immunotherapies for improved bladder cancer treatment

Cancer immunotherapy has rapidly become the fourth mainstream treatment alternative after surgery, radiotherapy, and chemotherapy, with some promising results. It aims to kill tumor cells by mobilizing or stimulating cytotoxic immune cells. However, the clinical applications of tumor immunotherapies are limited owing to a lack of adequate delivery pathways and high toxicity. Recently, nanomaterials and genetic engineering have shown great potential in overcoming these limitations by protecting the delivery of antigens, activating targeted T cells, modulating the immunosuppressive tumor microenvironment, and improving the treatment efficacy. Bacillus Calmette-Guérin (BCG) is a live attenuated Mycobacterium bovis vaccine used to prevent tuberculosis, which was first reported to have antitumor activity in 1927. BCG therapy can activate the immune system by inducing various cytokines and chemokines, and its specific immune and inflammatory responses exert antitumor effects. BCG was first used during the 1970s as an intravesical treatment agent for bladder cancer, which effectively improved immune antitumor activity and prevented tumor recurrence. More recently, nano-BCG and genetically engineered BCG have been proposed as treatment alternatives for bladder cancer due to their ability to induce stronger and more stable immune responses. In this study, we outline the development of nano-BCG and genetically engineered BCG for bladder cancer immunotherapy and review their potential and associated challenges.

Identification and validation of sialyltransferase ST3Gal5 in bladder cancer through bioinformatics and experimental analysis

BACKGROUND

Bladder cancer (BLCA) is one of the top ten most common cancers in the world. Aberrant sialylation is a common feature in tumorigenesis and tumor immunity. This study seeks to explore the potential impact of sialyltransferase ST3Gal5 on BLCA.

METHODS

Initially, glycosyltransferase-related DEGs (GRDEGs) were identified using multiple bioinformatics approaches in TCGA-BLCA cohort and validated using GEO databases. Clinical prognosis integration facilitated the determination of ST3Gal5 as an independent prognostic factor in BLCA, employing univariate and multivariate Cox regression analyses. Immune cell infiltration was assessed via CIBERSORT and ssGSEA analyses, while HLA and immune checkpoint genes' levels, along with drug sensitivity, were evaluated in low- and high-ST3Gal5 groups. The TIDE and IPS scores were used to gauge the immune checkpoint blockade (ICB) response. Furthermore, functional experiments, both in vivo and in vitro, were conducted to elucidate the biological roles of ST3Gal5.

RESULTS

In agreement with bioinformatics findings, ST3Gal5 expression was down-regulated in BLCA tissues and cells, correlating with poorer prognostic outcomes. The StromalScore, ImmuneScore, and ESTIMATEScore were significantly elevated in low-ST3Gal5 group. Moreover, the levels of HLA and immune checkpoint genes were upregulated in low-ST3Gal5 group. Down-regulated ST3Gal5 promoted the proliferation, migration, and invasion of BLCA cells in vivo and in vitro.

CONCLUSION

Our findings demonstrated that low ST3Gal5 level promoted tumorigenesis and progression of BLCA, implying its potential as a predictive biomarker and therapeutic target.

Cuproptosis-Related lncRNAs Modulate the Prognosis of MIBC by Regulating the Expression Pattern of Immunosuppressive Molecules Within the Tumor Microenvironment

Background

Cuproptosis-related gene and long non-coding RNA (lncRNA) modulation of cancer regulation is well-established. This investigation aimed to elucidate the prognostic implications of cuproptosis-associated lncRNAs in muscle-invasive bladder cancer (MIBC).

Methods

Employing the Cancer Genome Atlas (TCGA) and IMvigor210 cohorts, bioinformatics and statistical analyses probed the prognostic relevance of cuproptosis-related lncRNAs.

Results

Co-expression analysis revealed tight associations between lncRNA expression and cuproptosis-linked genes, with 13 cuproptosis-related lncRNAs found to correlate with MIBC prognosis. Lasso regression identified a six-lncRNA prognostic signature, enabling patient stratification into high- and low-risk categories. Tissue validation substantiated differential expression of FAM13A-AS1, GHRLOS, LINC00456, OPA1-AS1, RAP2C-AS1, and UBE2Q1-AS1 between MIBC tumor and normal tissues. Comparative analyses of tumor microenvironments and immune profiles between risk groups disclosed elevated immunosuppressive molecule expression, including programmed cell death-1 (PD-L1) and T-cell immunoglobulin-3 (TIM-3), in high-risk individuals.

Conclusion

These findings suggest that cuproptosis-related lncRNAs may modulate the expression of immunosuppressive molecules, thereby influencing MIBC tumorigenesis and progression. Further exploration is warranted to unveil novel therapeutic targets for MIBC based on the expression patterns of cuproptosis-related lncRNAs and their impact on immune responses in the tumor microenvironment.

Prevalence of metabolic acidosis in ileal diversions more than one year after radical cystectomy and associated secondary metabolic effects

INTRODUCTION AND OBJECTIVE

Metabolic acidosis (MA) is a well-known complication in patients with ileal urinary diversions. It is common in the early postoperative stages and decreases over time. Our objective is to investigate the prevalence of MA after more than one year of follow-up, identify the associated risk factors, and analyze its secondary metabolic consequences.

MATERIALS AND METHODS

We conducted an observational study between January 2018 and September 2022 following the STROBE guidelines. MA was defined as a serum bicarbonate level ​​<22mEq/L. Finally, we analyzed 133 patients with a mean follow-up of 55.24 ± 42.36 months.

RESULTS

MA was observed in 16 (12%) patients. Patients with and without MA were comparable in age, sex, and follow-up time. The group with MA presented a higher rate of anemia (68,75% vs 19,65%, p < 0.001) and renal failure (100% vs 45,29%, p < 0.001), statistically significant higher levels of serum creatinine, chloride, potassium, parathyroid hormone, and phosphorus but lower serum values ​​of hemoglobin, renal glomerular filtration rate, total cholesterol, vitamin D, calcium, and albumin (all p < 0.05). Renal glomerular filtration rate was the only independent risk factor related to the development of MA (OR 0.914; 95% CI 0.878-0.95; p < 0.0001), proving a close correlation with venous bicarbonate values ​​(r = 0.387, p < 0.001).

CONCLUSIONS

MA is a little prevalent disorder in ileal urinary diversions more than one year after radical cystectomy is performed but it has secondary consequences on hematologic, renal, protein, lipid, and bone metabolism. We recommend to a close follow-up in patients with renal failure for early diagnosis and treatment.

A novel signature constructed by differential genes of muscle-invasive and non-muscle-invasive bladder cancer for the prediction of prognosis in bladder cancer

Background

Bladder cancer (BCa) is a malignant tumor that usually forms cancer cells in the inner lining of the bladder. Hundreds of thousands of people worldwide have BCa diagnosed each year. The purpose of this study was to construct a prognostic model by differential expression of genes between muscular and non-muscular invasive BCa, and to investigate the prognosis of BCa patients.

Methods

The data of BCa patients was sourced from the GEO and TCGA database. Single-cell sequencing data was obtained from three patients in the GSE135337 database, and microarray data for verification was obtained from GSE32894. Univariate, Lasso and multivariate cox regression analyses were performed to construct the prognostic model. The prognostic features, immune features and drug sensitivity of the model were further evaluated. Single-cell data and microarray data were used to validate the differential expression of model genes between muscle-invasive and non-muscle-invasive BCa. The invasion and migration of BCa cells were evaluated using the transwell assay and wound-healing assay. The cell proliferation capacity was simultaneously evaluated using Colony formation experiments. The protein expression of the specific gene was detected by western blot analysis.

Results

We identified 183 differentially expressed muscle-invasive-related differential genes (MIRDGs), among which four were selected to establish a prognostic model. Based on our signature, patients in different groups displayed varying levels of immune infiltration and immunotherapy profiles. Single-cell sequencing data and microarray data confirmed that four invasion-related genes were expressed at higher levels in muscle-invasive BCa. Given the critical role of S100A9 in the progression of BCa, we performed further analysis. The results showed that protein expression of S100A9 was high in muscle-invasive BCa, and S100A9 knockdown could inhibit the proliferation, migration and invasion of BCa.

Conclusion

These findings demonstrated that the prognostic model for BCa patients was reasonably accurate and valid, and it may prove to be of considerable value for the treatment and prognosis of BCa patients in the future. S100A9 may become a better prognostic marker and potential therapeutic target to further guide clinical treatment decisions.

Metabolic acidosis after ileal urinary diversion and radical cystectomy. Do we know as much as we think we do? A systematic review

Urine contact with the mucosa of the urinary diversion (UD) after radical cystectomy (RC) produces different ion exchanges that favor the development of metabolic acidosis (MA). This phenomenon is a frequent cause of hospital readmission and short/long-term complications. We performed a systematic review of MA in RCs with ileal UD, analyzing its prevalence, diagnosis, risk factors and treatment. We systematically searched Pubmed® and Cochrane Library for original articles published before May 2022 according to PRISMA guidelines. A total of 421 articles were identified. We selected 25 studies that met the inclusion criteria involving 5811 patients. Obtaining precise data on the prevalence of MA is difficult, largely due to the heterogeneity of the diagnostic criteria used given the diversity of studies analyzed. Development of MA is multifactorial. In the early period, MA is more prevalent in patients with UD with longer ileal segments, better urinary continence, and impaired renal function. Age and diabetes are risk factors associated with MA in later periods. MA is the most common cause of second or more hospital readmissions. Prophylaxis with oral bicarbonate for three months in patients at risk could improve these results. Although MA after ileal UD is a well-known condition, this review highlights the need to implement homogeneous criteria for the diagnosis, follow-up, and treatment, in addition to protocolizing prevention/prophylaxis strategies in patients at risk.

Quality of life in patients with non-muscle invasive bladder tumor undergoing adjuvant intravesical treatment

INTRODUCTION

The objective of the study was to establish a possible relationship between mitomycin-C (MMC) and bacillus Calmette-Guérin (BCG) treatments and quality of life impairment.

MATERIAL AND METHODS

Quasi-experimental, prospective, and longitudinal study including patients undergoing adjuvant treatment in NMIBC. The Short form-12 (SF-12) and Urogenital Distress Inventory-6 (UDI-6) questionnaires were used to measure quality of life. Questionnaire scores were compared between cases with MMC and BCG before induction (M1), at 4 weeks (M2) and at 2 months (M3).

RESULTS

Of the 90 patients enrolled, 54 were in the BCG group and 36 in the MMC group. It was found that BCG patients had worse perceived physical quality of life compared to MMC patients in M2 (OR:2.59, p=0.046). In addition, significant changes were found in the urinary quality of life of patients on MMC treatment between the different time points (UDI-6 score: 33.33 in M1, 27.78 in M2 and 16.67 in M3, p=0.001).

CONCLUSIONS

There are no differences in urinary quality of life between patients treated with MMC and BCG. Patients with MMC show a significant recovery of urinary quality of life from the completion of the induction course, which becomes even more significant after 2 months. In addition, BCG-treated patients have worse physical quality of life after 4 weeks of treatment than those treated with MMC.

Immunotherapy for Bladder Cancer: Latest Advances and Ongoing Clinical Trials

For nearly 50 years, immunotherapy has been used in patients with bladder cancer in the form of Mycobacterium bovis Bacillus Calmette-Guerin (BCG), which is still the first-line therapy for non-muscle invasive disease. However, the remarkable results obtained with checkpoint inhibitor drugs, including Pembrolizumab and Atezolizumab, have fueled the quest to optimize these and other forms of immunotherapy for both non-muscle invasive as well as advanced bladder cancer. In this review we summarize the current state of the rapidly evolving field of immunotherapy in bladder cancer highlighting novel approaches and ongoing trials in this exciting area of research.

Antifungal immunity mediated by C-type lectin receptors may be a novel target in immunotherapy for urothelial bladder cancer

Immunotherapies, such as immune-checkpoint blockade and adoptive T-cell therapy, offer novel treatment options with good efficacy for patients with urothelial bladder cancer. However, heterogeneity and therapeutic resistance have limited the use of immunotherapy. Further research into immune-regulatory mechanisms in bladder cancer is urgently required. Emerging evidence demonstrates that the commensal microbiota and its interactions with host immunity play pivotal roles in a variety of physiological and pathological processes, including in cancer. The gut microbiota has been identified as a potentially effective target of treatment that can be synergized with immunotherapy. The urothelial tract is also a key site for multiple microbes, although the immune-regulatory role of the urinary microbiome in the process of carcinogenesis of bladder cancer remains to be elucidated. We performed a comprehensive analysis of the expression and biological functions of C-type lectin receptors (CLRs), which have been recognized as innate pathogen-associated receptors for fungal microbiota, in bladder cancer. In line with previous research on fungal colonization of the urothelial tract, we found that CLRs, including Dectin-1, Dectin-2, Dectin-3, and macrophage-inducible Ca²⁺-dependent lectin receptor (Mincle), had a significant association with immune infiltration in bladder cancer. Multiple innate and adaptive pathways are positively correlated with the upregulation of CLRs. In addition, we found a significant correlation between the expression of CLRs and a range of immune-checkpoint proteins in bladder cancer. Based on previous studies and our findings, we hypothesize that the urinary mycobiome plays a key role in the pathogenesis of bladder cancer and call for more research on CLR-mediated anti-fungal immunity against bladder cancer as a novel target for immunotherapy in urothelial bladder cancer.

New Perspectives in the Medical Treatment of Non-Muscle-Invasive Bladder Cancer: Immune Checkpoint Inhibitors and Beyond

Non-muscle-invasive bladder cancer (NMIBC) is characterized by a high rate of cure, but also by a non-negligible probability of recurrence and risk progression to muscle-invasive disease. NMIBC management requires a proper local resection and staging, followed by a risk-based treatment with intravesical agents. For many years, the current gold standard treatment for patients with intermediate or high-risk disease is transurethral resection of the bladder (TURB) followed by intravesical bacillus Calmette–Guérin (BCG) instillations. Unfortunately, in about half of high-risk patients, intravesical BCG treatment fails and NMIBC persists or recurs early. While radical cystectomy remains the gold standard for these patients, new therapeutic targets are being individuated and studied. Radical cystectomy in fact can provide an excellent long-term disease control, but can deeply interfere with quality of life. In particular, the enhanced immune checkpoints expression shown in BCG-unresponsive patients and the activity of immune checkpoints inhibitors (ICIs) in advanced bladder cancer provided the rationale for testing ICIs in NMIBC. Recently, pembrolizumab has shown promising activity in BCG-unresponsive NMIBC patients, obtaining FDA approval. Meanwhile multiple novel drugs with alternative mechanisms of action have proven to be safe and effective in NMIBC treatment and others are under investigation. The aim of this review is to analyse and describe the clinical activity of new emerging drugs in BCG-unresponsive NMIBC focusing on immunotherapy results.

Preoperative abdominal fat distribution and systemic immune inflammation were associated with response to intravesical Bacillus Calmette-Guerin immunotherapy in patients with non-muscle invasive bladder cancer

OBJECTIVE

To investigate the predictors of response to intravesical Bacillus Calmette-Guerin (BCG) immunotherapy for intermediate and high-risk non-muscle invasive bladder cancer (NMIBC) patients.

MATERIALS AND METHODS

We retrospectively analyzed the clinicopathological data of 184 intermediate and high risk NMIBC cases receiving transurethral resection of bladder tumor (TURBT) and intravesical BCG immunotherapy from December 2014 to April 2021 at our center. All patients were divided into BCG responders and non-responders. Multivariate Logistic regression analysis was performed to identify the independent predictors of response to intravesical BCG immunotherapy. Univariate and multivariate Cox regression analyses were applied to explore the independent prognostic factors of recurrence-free survival (RFS). Receiver operating characteristic (ROC) curve and Kaplan-Meier survival analysis were also utilized.

RESULTS

The RFS of BCG responders was significantly increased compared with BCG non-responders. Multivariate Cox regression analysis demonstrated that low grade, pTa stage, non-CIS, lower relative visceral fat area (rVFA) and lower systemic immune inflammation index (SII) were independent prognostic factors of increased RFS after intravesical BCG immunotherapy. Multivariate Logistic regression analysis demonstrated that pTa stage, low grade, non-CIS, low rVFA, and low SII were independent predictors of response to intravesical BCG immunotherapy. Kaplan-Meier survival analysis indicated that the RFS of patients in low rVFA group or low SII group was significantly increased in comparison with those in high rVFA group or high SII group. ROC curve analysis showed that the area under ROC (AUC) of including SII and rVFA was significantly increased, indicating that the inclusion of preoperative SII and rVFA could significantly improve the predictive efficiency.

CONCLUSIONS

Low grade, pTa stage, non-CIS, preoperative lower rVFA and lower SII were vital independent predictors of response to intravesical BCG immunotherapy and were associated with preferable prognosis in NMIBC patients. The inclusion of preoperative SII and rVFA could significantly improve the predictive efficiency.

Carbon ion radiotherapy for bladder cancer: A case report

BACKGROUND

Radical cystectomy is considered the first choice for the treatment of muscle-invasive bladder cancer. However, for some patients who have lost the indications for surgery, external beam radiotherapy is a non-invasive and effective treatment.

CASE SUMMARY

A 76-year-old patient with bladder cancer who had serious comorbidities and could not tolerate surgery or chemotherapy came to the Wuwei Heavy Ion Center. He received carbon ion radiotherapy (CIRT) with a whole-bladder dose of 44 GyE and tumor boost of 20 GyE. When he finished CIRT, his bladder cancer-related hematuria completely disappeared, and computed tomography examination showed that the tumor had obviously decreased in size. At the 3-mo follow-up, the tumor disappeared, and there were no acute or late adverse events. CIRT was well tolerated in this patient.

CONCLUSION

CIRT may allow for avoiding resection and was well tolerated with curative outcomes.