Apoptosis and its clinical significance for bladder cancer therapy

Prognostic value of COL10A1 and its correlation with tumor-infiltrating immune cells in urothelial bladder cancer: A comprehensive study based on bioinformatics and clinical analysis validation

Introduction

Bladder cancer (BLCA) is one of the most lethal diseases. COL10A1 is secreted small-chain collagen in the extracellular matrix associated with various tumors, including gastric, colon, breast, and lung cancer. However, the role of COL10A1 in BLCA remains unclear. This is the first research focusing on the prognostic value of COL10A1 in BLCA. In this research, we aimed to uncover the association between COL10A1 and the prognosis, as well as other clinicopathological parameters in BLCA.

Methods

We obtained gene expression profiles of BLCA and normal tissues from the TCGA, GEO, and ArrayExpress databases. Immunohistochemistry staining was performed to investigate the protein expression and prognostic value of COL10A1 in BLCA patients. GO and KEGG enrichment along with GSEA analyses were performed to reveal the biological functions and potential regulatory mechanisms of COL10A1 based on the gene co-expression network. We used the “maftools” R package to display the mutation profiles between the high and low COL10A1 groups. GIPIA2, TIMER, and CIBERSORT algorithms were utilized to explore the effect of COL10A1 on the tumor immune microenvironment.

Results

We found that COL10A1 was upregulated in the BLCA samples, and increased COL10A1 expression was related to poor overall survival. Functional annotation of 200 co-expressed genes positively correlated with COL10A1 expression, including GO, KEGG, and GSEA enrichment analyses, indicated that COL10A1 was basically involved in the extracellular matrix, protein modification, molecular binding, ECM-receptor interaction, protein digestion and absorption, focal adhesion, and PI3K-Akt signaling pathway. The most commonly mutated genes of BLCA were different between high and low COL10A1 groups. Tumor immune infiltrating analyses showed that COL10A1 might have an essential role in recruiting infiltrating immune cells and regulating immunity in BLCA, thus affecting prognosis. Finally, external datasets and biospecimens were used, and the results further validated the aberrant expression of COL10A1 in BLCA samples.

Conclusions

In conclusion, our study demonstrates that COL10A1 is an underlying prognostic and predictive biomarker in BLCA.

Pathobiology and chemoprevention of bladder cancer

Our understanding of the pathogenesis of bladder cancer has improved considerably over the past decade. Translating these novel pathobiological discoveries into therapies, prevention, or strategies to manage patients who are suspected to have or who have been diagnosed with bladder cancer is the ultimate goal. In particular, the chemoprevention of bladder cancer development is important, since urothelial cancer frequently recurs, even if the primary cancer is completely removed. The numerous alterations of both oncogenes and tumor suppressor genes that have been implicated in bladder carcinogenesis represent novel targets for therapy and prevention. In addition, knowledge about these genetic alterations will help provide a better understanding of the biological significance of preneoplastic lesions of bladder cancer. Animal models for investigating bladder cancer development and prevention can also be developed based on these alterations. This paper summarizes the results of recent preclinical and clinical chemoprevention studies and discusses screening for bladder cancer.

Role and rationale of gene therapy and other novel therapies in the management of NMIBC

Bladder cancer is the second most common urological malignancy with a one in 28 lifetime risk. Three-quarters of tumors are non-muscle-invasive (formerly termed superficial) at the time of presentation. Approximately half of all non-muscle-invasive bladder cancer (NMIBC) will recur and, depending on certain prognostic factors including grade, stage and presence of carcinoma in situ, a number will progress to muscle invasion. The standard of care for NMIBC is transurethral resection of bladder tumor (TURBT) to remove the mass lesion(s). Intravesical therapy of NMIBC post-TURBT therefore aims to delay/prevent recurrence and/or progression to muscle-invasive bladder cancer. While intravesical chemotherapy, such as mitomycin C, and immunotherapy, such as bacillus Calmette-Guérin are well established, there is current interest in novel therapies based on improved molecular understanding of bladder cancer. These novel therapies include gene therapy, using viral and non-viral vectors for transfer, monoclonal antibodies and direct tumoricidal viruses. While there is a sound theoretical basis for these therapies based on molecular targeting, there is little evidence in human studies that these therapies have clinical impact on NMIBC. However, it is certain that their use will be investigated further and they provide great hope for the future of NMIBC adjuvant therapy.

Caspase 9 and caspase 8 gene polymorphisms and susceptibility to bladder cancer in north Indian population

BACKGROUND

Dysregulation of apoptosis plays a crucial role in carcinogenesis. Our aim was to investigate the association of Caspase 9 and Caspase 8 gene polymorphism with bladder cancer (BC) susceptibility.

METHODS

We undertook a case-control study of 212 (BC) cases and 250 controls to investigate the association between Caspase 9-1263A > G, Caspase 9-293del, and Caspase 8-6 N ins/del polymorphism and BC susceptibility by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method, and further to study the influence on recurrence in patients after Bacillus Calmette-Guerin (BCG) immunotherapy.

RESULTS

Overall, no statistically significant association was observed in Caspase 9-293del and Caspase 8. Nevertheless, Caspase 9-1263GG genotype was at reduced risk of BC [p = 0.010; odds ratio (OR) = 0.487]. Caspase 9-1263AG genotype was also observed to be significantly associated with reduced risk with high-risk non-muscle-invasive bladder cancer (NMIBC) (TaG(2-3), T1G(1-3)) and invasive tumors (T2 +) of BC (P = 0.042, OR = 0.39 and P = 0.013, OR = 0.028 respectively). Caspase 9-293del, heterozygous (-/+) genotype, too, demonstrated protective effect in high-risk NMIBC (P = 0.017; OR = 0.205). Haplotype analysis revealed variant genotypes Caspase 9AG + GG/Caspase 8 DI + II to be at reduced risk of BC (= 0P.014, OR = 0.47). The GG genotype of Caspase 9-1263 was associated with reduced risk for recurrence in BCG-treated patients [hazard ratio (HR) = 0.217, P = 0.005], thus showing increased recurrence-free survival (log-rank P = 0.024).

CONCLUSION

Polymorphism in Caspase 9-1263 was observed to play a protective role in susceptibility to BC risk. Caspase 9 gene variants were also associated with reduced risk of NMBIC stages. The variant G allele at Caspase 9-1263 may be responsible for increased recurrence-free survival in BCG-treated patients.

Molecular markers for bladder cancer: the road to a multimarker approach

Bladder cancer is the seventh most common malignancy worldwide, with almost 14,000 patients dying from this disease in the USA alone. Because of the need for long-term and frequent follow-up, as well as the paucity of sensitive and specific noninvasive tests, bladder cancer management has the highest cost per patient among all cancer types. Several molecular markers, especially members of the cell cycle regulation and apoptosis pathways, have been investigated. However, no individual marker has been prognostically powerful enough to change clinical management. The combined analysis of a panel of markers spanning different pathways is the most promising approach. We give an overview of the most important molecular markers functioning in crucial pathways and focus on their role in multimarker analysis.

Molecular biology of bladder cancer: prognostic and clinical implications

The role of various molecular determinants involved in the genesis, progression, and outcome of bladder cancer has been the focus of investigations for the past 2 decades. Increasingly, the analysis of the interplay between these molecular factors is taking center stage. We review herein the studies examining the effects of deregulation of the various molecules implicated in the cell cycle, apoptosis, and angiogenesis pathways and analyze the central role of p53 in regulating these pathways. Technological advancements enable detection and quantification of gene transcripts and protein products, helping us move toward achieving the goal of establishing diagnostic, prognostic, and therapeutic marker panels. Recent studies have therefore focused on multiple-marker analyses to generate informative panels that can have greater clinical value for bladder cancer management. The use of molecular marker panels can provide a more objective alternative to clinical parameters for diagnosis and treatment decisions. Clinical trials aimed at treating urothelial carcinoma based on a patient's molecular profile can be predicted to empower clinicians to personalize patient management through increased therapeutic efficacy.

From microarrays to new therapeutic approaches in bladder cancer

Bladder cancer is a model tumor progressing from superficial to locally invasive and finally metastatic disease. The likelihood of progression is determined to a large extent by the molecular profile of the tumor. From the pre-genomic era only p53 emerged as the molecular prognostic factor able to add value to existing clinical and pathological features of bladder cancer, however it was not introduced to the clinic. Microarray technologies enable us to study expression of thousands of genes in the tumor tissue. This method has already proven to add information to clinical classifiers, to find new tumor suppressor genes and to define p53 related pathways of cell-cycle regulation. In the last decade, progress in the treatment of locally invasive and metastatic bladder cancer was minimal; large Phase III trials with neo/adjuvant chemotherapy were inconclusive. The new paradigm of treatment tailored to an individual patient could be realized in bladder cancer for his chronic clinical course with opportunities to obtain tumor samples for microarray studies. Molecular profiling of two samples taken at the superficial stage and at cystectomy should enable us to study the microevolution of the tumor, to tailor existing treatment options, and to introduce new biologicals to the clinic.Introduction

Prognostic factors in transitional cell cancer of the bladder: an emerging role for Bcl-2 and p53

BACKGROUND AND PURPOSE

In a recent study on patients with transitional cell cancer of the bladder treated with curative radiotherapy following TUR-T, we demonstrated that a low apoptotic index and p53 positivity were associated with poor local control. The purpose of this study was to assess the prognostic significance of additional markers implicated in regulation of cell cycle and apoptosis.

PATIENTS AND METHODS

Bcl-2, Bax and p21 positivity were detected immunohistochemically on paraffin-embedded pre-treatment biopsies from 83 patients with invasive transitional cell cancer (TCC) of the bladder, treated with radiotherapy. In addition, markers determined in an earlier analysis, i.e.: p53, apoptotic index, cyclin D1, retinoblastoma protein and Ki-67 were included in the multivariate analysis. A stepwise proportional hazard analysis was performed, adjusting for classic prognostic factors (T-stage, grade, multifocality and macroscopic completeness of the TUR). Positivity was defined as >10% of tumor cells staining positive for Bcl-2, Bax and p21, and >20% for p53.

RESULTS

Bcl-2 positivity was found in 63%, Bax was positive in 52% and p21 in 55% of cases. In the PH analysis Bcl-2 positivity was found to be related to poor local control (36 vs. 72% at 3 years; P=0.003), as well as to shorter disease-specific survival (74 vs. 94% at 3 years; P=0.017). Evidence for an adverse effect of p53 positivity was also found (local control: 32 vs. 69% at 3 years;P=0.037, disease-specific survival: 76 vs. 92% at 3 years; P=0.043). In an additional PH analysis, we found poor local control rates for bladder cancers with combined Bcl-2 and p53 positivity (17 vs. 65% at 3 years; P=0.0017), and lower disease specific survival (60 vs. 92%; P=0.0024), disease-free survival (7 vs.35%, P=0.0023) and overall survival (39 vs. 80%; P=0.0018).

CONCLUSION

This study provides evidence for a poor outcome in patients treated with radiotherapy for TCC of the bladder expressing both Bcl-2 and p53. This relationship was found for local control and disease-free, disease-specific and overall survival.

The effect of antisense Bcl-2 oligonucleotides on Bcl-2 protein expression and apoptosis in human bladder transitional cell carcinoma

PURPOSE

Bcl-2 is an important determinant of transitional cell carcinoma of the bladder recurrence and progression as well as a factor in patient response to chemotherapy or radiotherapy. We determined Bcl-2 down-regulation after antisense oligonucleotide therapy and synergism with mitomycin C in transitional cell carcinoma of the bladder.

MATERIALS AND METHODS

Bcl-2 protein was quantified using flow cytometry and immunohistochemistry in 4 bladder cancer cell lines, in bladder washings from 6 patients with carcinoma in situ and in 16 patient tumor samples. The synergistic effects of antisense oligonucleotides G3139 and 2009, and mitomycin C were investigated in 4 cell lines, while 2009 down-regulation was examined in 20 tumor explants in an ex vivo model.

RESULTS

Bcl-2 protein expression was found in all 4 cell lines and in 5 of the 6 cell populations derived from patients with carcinoma in situ. Of the 16 tumors 7 were classified positive by frozen section immunohistochemistry and quantitative flow cytometry. G3139 and 2009 down-regulated Bcl-2 protein expression in all 4 cell lines and 2009 down-regulated Bcl-2 protein expression in half of the Bcl-2 positive tumor specimens. There was only evidence in 1 cell line, T24/83, that Bcl-2 protein expression down-regulation enhanced mitomycin C induced apoptotic cell death.

CONCLUSIONS

Bcl-2 was expressed in a significant proportion of bladder tumors and in carcinoma in situ. Therefore, antisense oligonucleotides represent a viable strategy for Bcl-2 protein down-regulation. However, it may not always translate into an increased level of mitomycin C induced apoptosis in transitional cell carcinoma of the bladder.

Immunohistochemical analysis of Ki-67, p21waf1/cip1 and apoptosis in marker lesions from patients with superficial bladder tumours treated with vinorelbine intravesical therapy in a preliminary phase I trial

OBJECTIVE

To investigate Ki-67 and p21Waf1/Cip1 expression and apoptosis, before and after treatment, in tumour biopsies obtained from patients with superficial bladder cancer who underwent vinorelbine intravesical therapy.

PATIENTS AND METHODS

Twenty patients with high-risk superficial bladder cancer (including one or more of the following parameters: tumour diameter > 3 cm, histological grade 3, or multicentric tumours) were treated 1-6 times (weekly) with intravesical vinorelbine (50 mg/mL) instillations. Transurethral tumour marker biopsies were obtained one week before the first instillation of the drug and one week after the last. The biopsies were immunostained for Ki-67 and p21Waf1/Cip1 with monoclonal antibodies, on tissue sections derived from paraffin-embedded samples obtained before and after vinorelbine treatments. In addition, apoptosis was determined using a terminal deoxynucleotidyl transferase-mediated dUTP biotin nick-end labelling (TUNEL) technique.

RESULTS

There were no significant differences in the cell proliferation marker Ki-67 in biopsies taken before or after treatment. However, p21Waf1/Cip1 showed significantly higher expression in biopsies obtained after vinorelbine treatment, with median (range) values of 40 (20-90)% before and 70 (50-80)% after (P < 0.001, paired nonparametric Wilcoxon test). The apoptotic index was significantly higher after vinorelbine therapy, with median (range) values of 0.89 (0.06-3.8)% before and 2.25 (0.17-18.7)% after treatment (P < 0.001, paired nonparametric Wilcoxon test). Despite the brief treatment and few patients there was a clinical response in nine patients, together with low toxicity in all.

CONCLUSION

The intravesical treatment of tumours with vinorelbine affects p21Waf1/Cip1 expression without blocking cell proliferation, although increasing apoptosis. The preliminary results suggest that vinorelbine may be useful for treating superficial bladder tumours, and thus a phase II study is warranted.