Bladder Cancer in the Genomic Era

Molecular profile of bladder cancer progression to clinically aggressive subtypes

Bladder cancer is a histologically and clinically heterogenous disease. Most bladder cancers are urothelial carcinomas, which frequently develop distinct histological subtypes. Several urothelial carcinoma histological subtypes, such as micropapillary, plasmacytoid, small-cell carcinoma and sarcomatoid, show highly aggressive behaviour and pose unique challenges in diagnosis and treatment. Comprehensive genomic characterizations of the urothelial carcinoma subtypes have revealed that they probably arise from a precursor subset of conventional urothelial carcinomas that belong to different molecular subtypes - micropapillary and plasmacytoid subtypes develop along the luminal pathway, whereas small-cell and sarcomatoid subtypes evolve along the basal pathway. The subtypes exhibit distinct genomic alterations, but in most cases their biological properties seem to be primarily determined by specific gene expression profiles, including epithelial-mesenchymal transition, urothelial-to-neural lineage plasticity, and immune infiltration with distinct upregulation of immune regulatory genes. These breakthrough studies have transformed our view of bladder cancer histological subtype biology, generated new hypotheses for therapy and chemoresistance, and facilitated the discovery of new therapeutic targets.

Integrative Single Cell Atlas Revealed Intratumoral Heterogeneity Generation from an Adaptive Epigenetic Cell State in Human Bladder Urothelial Carcinoma

Intratumor heterogeneity (ITH) of bladder cancer (BLCA) contributes to therapy resistance and immune evasion affecting clinical prognosis. The molecular and cellular mechanisms contributing to BLCA ITH generation remain elusive. It is found that a TM4SF1-positive cancer subpopulation (TPCS) can generate ITH in BLCA, evidenced by integrative single cell atlas analysis. Extensive profiling of the epigenome and transcriptome of all stages of BLCA revealed their evolutionary trajectories. Distinct ancestor cells gave rise to low-grade noninvasive and high-grade invasive BLCA. Epigenome reprograming led to transcriptional heterogeneity in BLCA. During early oncogenesis, epithelial-to-mesenchymal transition generated TPCS. TPCS has stem-cell-like properties and exhibited transcriptional plasticity, priming the development of transcriptionally heterogeneous descendent cell lineages. Moreover, TPCS prevalence in tumor is associated with advanced stage cancer and poor prognosis. The results of this study suggested that bladder cancer interacts with its environment by acquiring a stem cell-like epigenomic landscape, which might generate ITH without additional genetic diversification.

Proteomic analysis of the urothelial cancer landscape

Urothelial bladder cancer (UC) has a wide tumor biological spectrum with challenging prognostic stratification and relevant therapy-associated morbidity. Most molecular classifications relate only indirectly to the therapeutically relevant protein level. We improve the pre-analytics of clinical samples for proteome analyses and characterize a cohort of 434 samples with 242 tumors and 192 paired normal mucosae covering the full range of UC. We evaluate sample-wise tumor specificity and rank biomarkers by target relevance. We identify robust proteomic subtypes with prognostic information independent from histopathological groups. In silico drug prediction suggests efficacy of several compounds hitherto not in clinical use. Both in silico and in vitro data indicate predictive value of the proteomic clusters for these drugs. We underline that proteomics is relevant for personalized oncology and provide abundance and tumor specificity data for a large part of the UC proteome ( www.cancerproteins.org ).

A deep-learning workflow to predict upper tract urothelial carcinoma protein-based subtypes from H&E slides supporting the prioritization of patients for molecular testing

Upper tract urothelial carcinoma (UTUC) is a rare and aggressive, yet understudied, urothelial carcinoma (UC). The more frequent UC of the bladder comprises several molecular subtypes, associated with different targeted therapies and overlapping with protein-based subtypes. However, if and how these findings extend to UTUC remains unclear. Artificial intelligence-based approaches could help elucidate UTUC's biology and extend access to targeted treatments to a wider patient audience. Here, UTUC protein-based subtypes were identified, and a deep-learning (DL) workflow was developed to predict them directly from routine histopathological H&E slides. Protein-based subtypes in a retrospective cohort of 163 invasive tumors were assigned by hierarchical clustering of the immunohistochemical expression of three luminal (FOXA1, GATA3, and CK20) and three basal (CD44, CK5, and CK14) markers. Cluster analysis identified distinctive luminal (N = 80) and basal (N = 42) subtypes. The luminal subtype mostly included pushing, papillary tumors, whereas the basal subtype diffusely infiltrating, non-papillary tumors. DL model building relied on a transfer-learning approach by fine-tuning a pre-trained ResNet50. Classification performance was measured via three-fold repeated cross-validation. A mean area under the receiver operating characteristic curve of 0.83 (95% CI: 0.67-0.99), 0.8 (95% CI: 0.62-0.99), and 0.81 (95% CI: 0.65-0.96) was reached in the three repetitions. High-confidence DL-based predicted subtypes showed significant associations (p < 0.001) with morphological features, i.e. tumor type, histological subtypes, and infiltration type. Furthermore, a significant association was found with programmed cell death ligand 1 (PD-L1) combined positive score (p < 0.001) and FGFR3 mutational status (p = 0.002), with high-confidence basal predictions containing a higher proportion of PD-L1 positive samples and high-confidence luminal predictions a higher proportion of FGFR3-mutated samples. Testing of the DL model on an independent cohort highlighted the importance to accommodate histological subtypes. Taken together, our DL workflow can predict protein-based UTUC subtypes, associated with the presence of targetable alterations, directly from H&E slides.

Prognostic Value of Fatty Acid Metabolism-related Genes in Patients with Bladder Cancer

INTRODUCTION

This study aimed to explore the expression profiles of fatty acid metabolism- related genes (FAMRGs) in patients with bladder cancer (BLCA).

METHODS

The corresponding clinicopathological features of BLCA patients and RNA sequencing data were downloaded from TCGA and GSE13507. Univariate Cox regression was used to determine the prognostic value of FRGS in BLCA patients. LASSO regression analysis was then performed to select potential risk genes and eliminate genes that might overfit the model. Based on the independent prognostication-related FRGs, the nomogram survival model was established using the root mean square value of the R packet to predict the 1-year, 3-year, and 5-year survival rates of BLCA patients. By determining the area under the curve (AUC) value, the time-dependent receiver operating characteristic curve (ROC) was used to evaluate the prognostic efficiency of our model.

RESULTS

A total of 243 DEFRGs were identified. Twenty FRGs were found to be related to the prognosis of BLCA in the TCGA database. Survival curves showed that high-risk patients had significantly shorter OS than low-risk cases (p < 0.001). The AUC of risk was 0.784, which was superior to age, sex, and stage, suggesting that the risk score was more favorable in predicting OS than traditional pathologic prognostic factors. The AUC was 0.757 at 1 year, 0.732 at 3 years, and 0.733 at 5 year-OS.

CONCLUSION

In this study, we demonstrated that a FAMRG prognosis biomarker is associated with the tumor immune microenvironment in patients with BLCA.

Genetic Polymorphisms Involved in Bladder Cancer: A Global Review

Bladder cancer (BC) has been associated with genetic susceptibility. Single peptide polymorphisms (SNPs) can modulate BC susceptibility. A literature search was performed covering the period between January 2000 and October 2020. Overall, 334 articles were selected, reporting 455 SNPs located in 244 genes. The selected 455 SNPs were further investigated. All SNPs that were associated with smoking and environmental exposure were excluded from this study. A total of 197 genes and 343 SNPs were found to be associated with BC, among which 177 genes and 291 SNPs had congruent results across all available studies. These genes and SNPs were classified into eight different categories according to their function.

Highly Expressed LINC00958 Modulates the Growth and Epithelial-Mesenchymal Transition of Bladder Cancer Cells Through SAPK/JNK Signaling Pathway

Objective: To determine the expression of LINC00958 (BLACAT2) in bladder cancer (BC), the most common malignancy in the urinary system, and to determine its exact mechanism of action, so as to provide novel references for future clinical diagnosis and treatment of BC and lay a foundation for the follow-up research on LINC00958. Materials and Methods: Human bladder transitional cell carcinoma cells (T24 and J82) and human normal urothelial cells (SV-HUC-1) were purchased to detect the expression of LINC00958 and SAPK/JNK signaling pathway-related proteins. sh-LINC00958 targeting to silence LINC00958 expression and corresponding negative blank (sh-Control) were transfected into T24 and J82. Additionally, BC cells cultured with SP600125 (SP600125 group), a specific inhibitor of SAPK/JNK signaling pathway, and those cultured with the same amount of normal saline (Blank group) were also constructed. Cell growth capacity, cell invasiveness, and expression of epithelial-mesenchymal transition (EMT)-associated proteins were determined using CCK-8 & clone formation assays, Transwell assay, and Western blot, respectively. Results: The online databases Gene Expression Profiling Interactive Analysis, European Bioinformatics Institute, and StarBase revealed elevated LINC00958 expression in BC, and a potential association between LINC00958 and patient prognosis and survival. PCR results showed that LINC00958 was increased in T24 and J82 compared with the sh-Control group (p < 0.05). The results of biological behavior test revealed that the proliferation and invasiveness capacity of the sh-LINC00958 group decreased, while that of the SP600125 group increased compared with the Blank group (both p < 0.05). In the rescue experiment, the influence of sh-LINC00958 on BC cells was completely reversed by SP600125 (p > 0.05); In addition, the expression of E-cadherin, an EMT marker protein, was lower compared with the SH-LINC0958 group, while the Vimentin expression was higher (p < 0.05). Similarly, the wound-healing assay determined reduced cell healing rate in the sh-LINC00958 group (p < 0.05), and there was no difference between the sh-LINC00958+SP600125 group and the sh-Control group (p > 0.05). Conclusion: LINC00958 shows elevated expression in BC and promotes the growth and EMT of BC cell via inhibiting the SAPK/JNK signaling pathway, which has important potential as a new clinical diagnostic marker and therapeutic target for BC.

Recent Advances in the Classification of Bladder Cancer - Updates from the 5th Edition of the World Health Organization Classification of the Urinary and Male Genital Tumors

BACKGROUND

The World Health Organization Classification (WHO) of Urinary and Male Genital Tumors has recently been updated to its 5th edition. The new edition presents a comprehensive approach to the classification of urinary and male genital tumors with an incorporation of morphologic, clinical, and genomic data.

OBJECTIVE

This review aims to update the new classification of bladder cancer in the 5th edition and to highlight important changes in nomenclatures, diagnostic criteria, and molecular characterization, as compared to the 4th edition.

METHODS

The pathologic classification of bladder cancer in the 5th edition of WHO Classification of Urinary and Male Genital Tumours was compared to that in the 4th edition. PubMed was searched using key words, including bladder cancer, WHO 1973, WHO 1998, WHO 2004, WHO 2016, histology, pathology, genomics, and molecular classification in the time frame from 1973 to August of 2022. Other relevant papers were also consulted, resulting in the selection of 81 papers as references.

RESULTS

The binary grading of papillary urothelial carcinoma (UC) is practical, but it may be oversimplified and contribute to "grade migration" in recent years. An arbitrary cutoff (5%) has been proposed for bladder cancers with mixed grades. The diagnosis of papillary urothelial neoplasm with low malignant potential has been dramatically reduced in recent years because of overlapping morphology and treatment with low-grade papillary UC. An inverted growth pattern should be distinguished from true (or destructive) stromal invasion in papillary UC. Several methods have been proposed for pT1 tumor substaging, but it is often challenging to substage pT1 tumors in small biopsy specimens. Bladder UC shows a high tendency for divergent differentiation, leading to several distinct histologic subtypes associated with an aggressive clinical behavior. Molecular classification based on the genomic analysis may be a useful tool in the stratification of patients for optimal treatment.

CONCLUSIONS

The 5th edition of WHO Classification of Urinary and Male Genital Tumours has made several significant changes in the classification of bladder cancer. It is important to be aware of these changes and to incorporate them into routine clinical practice.

Molecular genetic and clinical characteristic analysis of primary signet ring cell carcinoma of urinary bladder identified by a novel OR2L5 mutation

To get a better understanding of the genetic basis of primary signet ring cell carcinoma (SRCC) of the bladder, which is highly rare and not yet explored. First, by using immunohistochemistry to find histological pathological characteristics. Second, a massively parallel whole-exome sequencing (WES) was performed on a 58-year-old male patient who had painless macroscopic hematuria and was pathologically diagnosed with primary SRCC of the bladder, followed by comparing with genes of ordinary urothelial cancer (UC) from TCGA. Furthermore, a population-based analysis using the SEER database was performed to investigate the prognosis (SRCC vs. UC). We identified 63 copy number variations (CNVs) with gain counts and 181 CNVs with loss counts. Totally 4515 mutations were discovered in C > T with a success rate of greater than 89%. The most frequently mutated pathway was RTK-RAS which has 85 genes involved in carcinogenic signaling. Final screening on predisposing genes is performed after filtering based on ACMG. Moreover, several driver genes, including NBN, KCTD18, SPATA13, ANKRD36, OR2L5, MALRD1, and LSMEM1, were detected. Sanger sequencing of germline DNA revealed the presence of a mutant base A/G of OR2L5 in the sequence, which was discovered for the first time in primary SRCC of the bladder. Furthermore, the immunohistochemical profile showed that primary SRCC of the bladder were positive for CK7, CK20, GATA-3, and expression of CK(AE1/AE2), EMA, and Ki67. In the SEER-based study, the patients with primary SRCC of the bladder got a worse prognosis compared to those with UC with median months overall survival (OS) 14 vs. 41, respectively, P = 0001, even after adjusting the variables in the Cox regression model, the SRCC of the bladder showed worse survival HR = 1.119, 95% CI = (1.081-1.328), P = 0.0001. These results imply that suppression of potential driver mutations may be a viable adjuvant treatment approach for primary SRCC in the bladder in place of standard chemotherapy, a possibility that warrants further clinical investigation.

Evaluation of grade and invasiveness of bladder urothelial carcinoma using infrared imaging and machine learning

Urothelial bladder carcinoma (BC) is primarily diagnosed with a subjective examination of biopsies by histopathologists, but accurate diagnosis remains time-consuming and of low diagnostic accuracy, especially for low grade non-invasive BC. We propose a novel approach for high-throughput BC evaluation by combining infrared (IR) microscopy of bladder sections with machine learning (partial least squares-discriminant analysis) to provide an automated prediction of the presence of cancer, invasiveness and grade. Cystoscopic biopsies from 50 patients with clinical suspicion of BC were histologically examined to assign grades and stages. Adjacent tissue cross-sections were IR imaged to provide hyperspectral datasets and cluster analysis segregated IR images to extract the average spectra of epithelial and subepithelial tissues. Discriminant models, which were validated using repeated random sampling double cross-validation, showed sensitivities (AUROC) ca. 85% (0.85) for the identification of cancer in epithelium and subepithelium. The diagnosis of non-invasive and invasive cases showed sensitivity values around 80% (0.84-0.85) and 76% (0.73-0.80), respectively, while the identification of low and high grade BC showed higher sensitivity values 87-88% (0.91-0.92). Finally, models for the discrimination between cancers with different invasiveness and grades showed more modest AUROC values (0.67-0.72). This proves the high potential of IR imaging in the development of ancillary platforms to screen bladder biopsies.

Immunohistochemical Algorithm for the Classification of Muscle-Invasive Urinary Bladder Carcinoma with Lymph Node Metastasis: An Institutional Study

Muscle-invasive urothelial carcinoma represents 20% of newly diagnosed cases of bladder cancer, and most cases show aggressive biological behavior with a poor prognosis. It is necessary to identify biomarkers that can be used as prognostic and predictive factors in daily clinical practice. In our study, we analyzed different antibodies in selected cases of muscle-invasive urinary bladder carcinoma and lymph node metastasis to identify immunohistochemical types and their value as possible prognostic factors. A total of 38 patients were included, 87% men and 13% women, with a mean age of 67.8 years. The most frequent histopathological type was urothelial carcinoma. In the primary lesion, the mixed type was the most common. In unilateral metastasis, the mixed type was the most frequently found. In cases of primary lesions and bilateral metastasis, the luminal and mixed types were observed. The luminal subtype was the most stable in immunohistochemical expression across primary tumors and metastases. The basal type showed a better prognosis in terms of disease-free survival. In conclusion, immunohistochemical studies are useful in assessing primary and metastatic lesions in patients with urothelial carcinoma. Immunohistochemical classification can typify muscle-invasive urothelial carcinoma, and the immunophenotype seems to have prognostic implications.

Investigation of prognostic biomarkers in patients with urothelial carcinoma treated with platinum-based regimens

BACKGROUND

Bladder cancer (BC) is a heterogeneous malignancy with dismal outcome.

PATIENTS AND METHODS

Mutations in genes, altered or linked to platinum sensitivity in BC, were examined in 66 patients' tumors along with tumor infiltrating lymphocytes (TILs) density and MMR, PD-L1 and CD8 protein expression, as well as basal and luminal subtypes, defined by protein expression of markers, including CK5/6 and GATA3 or CK20, respectively.

RESULTS

41 tumors harbored mutations, mainly in TP53 (38%), ARID1A (17%) and the DNA damage response and repair (DDR) genes ERCC2 (17%) and BRCA2 (15%). Mutations in other DDR relevant genes were also present. Age showed unfavorable prognosis for overall survival (HR=1.07, P = 0.026); no benefit was seen for patients with TP53, ARID1A, ERCC2 or BRCA2 mutations or mutations in 1 or more DDR genes. PD-L1 status positively correlated with stromal (rho=0.46, P < 0.001) and intratumoral (rho=0.53, P < 0.001) CD8 expression or TILs (rho=0.29, P = 0.018); none associated with overall survival (OS). A statistically significant difference was observed between PD-L1 status and immunohistochemistry (IHC)‑based subtypes, with tumors classified as luminal (GATA3+ and/or CK20+ and CK5/6-) showing lower PD-L1 expression relative to basal (CK5/6+ and GATA3- and/or CK20-) (median value 0 vs. 2.5, P = 0.029). Concerning OS, no statistically significant difference was seen among patients with basal or luminal tumors.

CONCLUSION

No association was seen herein between DDR mutations, TILs, PD-L1, CD8 expression or IHC-based subtypes and patient survival; these observations warrant validation within a larger cohort.

Molecular Taxonomy and Immune Checkpoint Therapy in Bladder Cancer

Bladder cancer is a heterogeneous disease, which exhibits a wide spectrum of clinical and pathologic features. Recent genomic studies have revealed that distinct molecular alterations may underlie the diverse clinical behaviors of bladder cancer, leading to a novel molecular classification. The intrinsic molecular subtypes exhibit distinct gene expression signatures and different clinicopathologic features. Genomic alterations also underlie the development of bladder cancer histologic subtypes. Genomic characterization provides new insights to understanding the biology of bladder cancer and improves the diagnosis and treatment of this complex disease. Biomarkers can aid the selection of patients for immune checkpoint therapy.

The 2022 ENCR Recommendations on recording and reporting of urothelial tumours of the urinary tract

An updated European Network of Cancer registries (ENCR) Recommendations on Recording and Reporting of Urothelial Tumours of the Urinary Tract had been published in 2022. After the publication by the ENCR of the "Recommendations for coding bladder cancers" in 1995, knowledge about the biology and pathology of urinary tract tumors and their classification has varied and increased substantially. On the other hand, several studies have shown that cancer registries use different definitions, criteria for inclusion and coding of urothelial tumors. This great variability among registries affects not only the criteria for recording (registration, coding and classification) but also the criteria of reporting (counting in the statistics of incidence and survival) urinary tract tumors. This causes difficulties in the data comparability from different registries. Recording and reporting of urothelial tumors requires the application of standard criteria that must take into account the combination of the multiple aspects as the primary topography, the histological type, the grade, the extent of invasion, the multi-centricity, the progressions and the time interval between tumors. This led to the creation of a Working Group of the ENCR that developed these recommendations on the recording and reporting of urothelial tumors of the urinary tract. This article reports these recommendations and the rationale for each.

Chronic Arsenic Exposure Upregulates the Expression of Basal Transcriptional Factors and Increases Invasiveness of the Non-Muscle Invasive Papillary Bladder Cancer Line RT4

The bladder is a target organ for inorganic arsenic, a carcinogen and common environmental contaminant found in soil and water. Urothelial carcinoma (UC) is the most common type of bladder cancer (BC) that develops into papillary or non-papillary tumors. Papillary tumors are mostly non-muscle invasive (NMIUC), easier treated, and have a better prognosis. Urothelial carcinoma can be molecularly sub-typed as luminal or basal, with papillary tumors generally falling into the luminal category and basal tumors exclusively forming muscle invasive urothelial carcinomas (MIUC). It is unclear why some UCs develop more aggressive basal phenotypes. We hypothesized that chronic arsenic exposure of a papillary luminal bladder cancer would lead to the development of basal characteristics and increase in invasiveness. We treated the human papillary bladder cancer cell line RT4 with 1 µM arsenite (As³⁺) for twenty passages. Throughout the study, key luminal and basal gene/protein markers in the exposed cells were evaluated and at passage twenty, the cells were injected into athymic mice to evaluate tumor histology and measure protein markers using immunohistochemistry. Our data indicates that chronic As³⁺- treatment altered cellular morphology and decreased several luminal markers in cell culture. The histology of the tumors generated from the As³⁺-exposed cells was similar to the parent (non-treated) however, they appeared to be more invasive in the liver and displayed elevated levels of some basal markers. Our study demonstrates that chronic As³⁺ exposure is able to convert a non-invasive papillary bladder cancer to an invasive form that acquires some basal characteristics.

Flat intraurothelial lesions of the urinary bladder-do hyperplasia, dysplasia, and atypia of unknown significance need to exist as diagnostic entities? and how to handle in routine clinical practice

Classification of the putative flat preneoplastic and neoplastic lesions of the urothelium with features subthreshold for urothelial carcinoma in situ remains a challenging, indeed, vexing problem in diagnostic surgical pathology. This area, subtending lesions including flat urothelial hyperplasia, urothelial dysplasia, and atypia of unknown significance, has struggled under evolving classifications, changing criteria, and limited clinical actionability, all confounded by the recognized lack of diagnostic reproducibility. Herein, we review the state of the literature around these lesions, reviewing contemporary criteria and definitions, assessing the arguments in favor and against of retaining hyperplasia, dysplasia, and atypia of unknown significance as diagnostic entities. We clarify the intent of the original definitions for dysplasia as a lesion felt to be clearly neoplastic but with morphologic features that fall short of the threshold of urothelial carcinoma in situ. While several pathologists, including some experts in the field, conflate the term dysplasia with urothelial atypia of unknown significance, the latter is defined as a descriptive diagnosis term to express diagnostic uncertainty of a lesion of whether it is clearly reactive or neoplastic. Both molecular studies and clinical needs are considered, as we outline our approach on diagnosing each of these lesions in clinical practice. Recommendations are made to guide consistency and interoperability in future scholarship, and the place of these lesions in context of evolving trends in the field is considered.

Identification of Epigenetic Interactions between miRNA and Gene Expression as Potential Prognostic Markers in Bladder Cancer

Purpose: To identify the role of a set of microRNAs and their target genes and protein expression levels in the pathogenesis of bladder cancer with a muscular invasion (T2−T4) and non-muscular invasion (T1). Methods: In 157 patients, bladder specimen was examined for the expression of a set of miRNAs including let-7a-5p, miRNA-449a-5p, miRNA-145-3P, miRNA-124-3P, miRNA-138-5p, and miRNA-23a-5p and their targeted genes; β-catenin, WNT7A, IRS2, FZD4, SOS1, HDAC1, HDAC2, HIF1α, and PTEN using the qRT-PCR technique. The prognostic effect of miRNAs and their targeted genes on cancer-specific survival (CSS) was evaluated in pT2−pT4 stages. Results: pT1 was found in 40 patients while pT2−4 was found in 117 patients. The expression of let-7a-5P, miR-124-3P, miR-449a-5P, and miR-138-5P significantly decreased in pT2−4 compared with pT1 (p < 0.001), in contrast, miR-23a-5P increased significantly in pT2−pT4 compared with pT1 (p < 0.001). Moreover, the expression of miR-145 did not show a significant change (p = 0.31). Higher expression levels of WNT7A, β-catenin, IRS2, FZD4, and SOS1 genes were observed in pT2−pT4 compared with pT1, whereas HDAC1, HDAC2, HIF1α, and PTEN genes were downregulated in pT2−pT4 compared with pT1. Lower CSS was significantly associated with lower expression of let-7a-5P, miR-124-3P, miR-449a-5P, and miR-138-5P. Higher expression of β-catenin, FZD4, IRS2, WNT7a, and SOS1 was significantly associated with worse CSS. In contrast, lower levels of HDAC1, HDAC2, HIF1α, and PTEN were associated with lower CSS. Conclusion: Our results support let-7a-5P, miR-124-3P, miR-138-5P, and their target genes can be developed as accurate biomarkers for prognosis in bladder cancer with a muscular invasion.

Are We Ready to Implement Molecular Subtyping of Bladder Cancer in Clinical Practice? Part 2: Subtypes and Divergent Differentiation

Following several attempts to achieve a molecular stratification of bladder cancer (BC) over the last decade, a "consensus" classification has been recently developed to provide a common base for the molecular classification of bladder cancer (BC), encompassing a six-cluster scheme with distinct prognostic and predictive characteristics. In order to implement molecular subtyping (MS) as a risk stratification tool in routine practice, immunohistochemistry (IHC) has been explored as a readily accessible, relatively inexpensive, standardized surrogate method, achieving promising results in different clinical settings. The second part of this review deals with the pathological and clinical features of the molecular clusters, both in conventional and divergent urothelial carcinoma, with a focus on the role of IHC-based subtyping.

Are We Ready to Implement Molecular Subtyping of Bladder Cancer in Clinical Practice? Part 1: General Issues and Marker Expression

Bladder cancer (BC) is a heterogeneous disease with highly variable clinical and pathological features, and resulting in different outcomes. Such heterogeneity ensues from distinct pathogenetic mechanisms and may consistently affect treatment responses in single patients. Thus, over the last few years, several groups have developed molecular classification schemes for BC, mainly based on their mRNA expression profiles. A “consensus” classification has recently been proposed to combine the published systems, agreeing on a six-cluster scheme with distinct prognostic and predictive features. In order to implement molecular subtyping as a risk-stratification tool in routine practice, immunohistochemistry (IHC) has been explored as a readily accessible, relatively inexpensive, standardized surrogate method, achieving promising results in different clinical settings. The first part of this review deals with the steps resulting in the development of a molecular subtyping of BC, its prognostic and predictive implications, and the main features of immunohistochemical markers used as surrogates to stratify BC into pre-defined molecular clusters.

Prediction of recurrence of non-muscle invasive bladder cancer: The role of androgen receptor and miRNA-2909

AIM

The exact role of androgen receptor (AR) and miR-2909 in non-muscle invasive bladder cancer (NMIBC) remains controversial. Our aim is to assess the relationship between NMIBC recurrences with AR expression and miRNA-2909.

PATIENTS AND METHODS

This prospective controlled cohort study included 99 male patients with NMIBC (Ta-T1) who were treated by transurethral resection and 50 male patients as healthy control. We quantified blood AR messenger RNA variants 1 and 2 (AR1, AR2) and plasma miRNA-2909 with real-time quantitative polymerase chain reaction and the full length AR (AR-FL) using enzyme-linked immunosorbent assay in serum samples. In addition, AR1 and AR2 expression in tumor as well as normal tissues were analyzed. Kaplan-Meier survival curves and multivariate Cox analysis were used to identify independent predictors of recurrence-free survival.

RESULTS

In comparison to control group, blood AR1, AR2, and serum AR-FL expression were significantly lower in the NMIBC group compared to plasma miRNA-2909 expression that was significantly higher in the control group. Blood AR1, AR2, and serum AR-FL were significantly correlated with higher tumor stage (pT1) while plasma miRNA-2909 was not. The median survival time (months) was significantly better for higher blood AR1 (34 vs. 21; P = 0.03), lower plasma miRNA-2909 (29 vs. 8; P <0.001), lower AR2 in normal tissues (32 vs. 22; P = 0.007). On multivariate analysis, serum free testosterone (hazards ratio [HR]: 8.9; 95% CI: 1.8-45.1; P = 0.008), serum AR1 (HR: 0.5; 95% CI: 0.3-0.9; P = 0.02), and plasma miRNA-2909 (HR: 5.8; 95% CI: 2.3-14.7; P = 0.0002), and tissue AR2 (HR: 2.6; 95% CI: 1.4-4.7; P = 0.002) were independent predictor for NMIBC recurrence.

CONCLUSIONS

Blood and tissue levels of AR expression have a potential significant effect on NMIBC recurrence. Further studies are recommended to establish its exact role.

Identification and Quantification of Iron Metabolism Landscape on Therapy and Prognosis in Bladder Cancer

The morbidity of bladder cancer (BLCA) is high and has gradually elevated in recent years. BLCA is also characterized by high recurrence and high invasiveness. Due to the drug resistance and lack of effective prognostic indicators, the prognosis of patients with BLCA is greatly affected. Iron metabolism is considered to be a pivot of tumor occurrence, progression, and tumor microenvironment (TME) in tumors, but there is little research in BLCA. Herein, we used univariate COX regression analysis to screen 95 prognosis-related iron metabolism-related genes (IMRGs) according to transcription RNA sequencing and prognosis information of the Cancer Genome Atlas (TCGA) database. TCGA-BLCA cohort was clustered into four distinct iron metabolism patterns (C1, C2, C3, and C4) by the non-negative matrix factorization (NMF) algorithm. Survival analysis showed that C1 and C3 patterns had a better prognosis. Gene set variant analysis (GSVA) revealed that C2 and C4 patterns were mostly enriched in carcinogenic and immune activation pathways. ESTIMATE and single sample gene set enrichment analysis (ssGSEA) also confirmed the level of immune cell infiltration in C2 and C4 patterns was significantly elevated. Moreover, the immune checkpoint genes in C2 and C4 patterns were observably overexpressed. Studies on somatic mutations showed that the tumor mutation burden (TMB) of C1 and C4 patterns was the lowest. Chemotherapy response assessment revealed that C2 pattern was the most sensitive to chemotherapy, while C3 pattern was the most insensitive. Then we established the IMRG prognosis signature (IMRGscore) by the least absolute shrinkage and selection operator (LASSO), including 13 IMRGs (TCIRG1, CTSE, ATP6V0A1, CYP2C8, RNF19A, CYP4Z1, YPEL5, PLOD1, BMP6, CAST, SCD, IFNG, and ASIC3). We confirmed IMRGscore could be utilized as an independent prognostic indicator. Therefore, validation and quantification of iron metabolism landscapes will help us comprehend the formation of the BLCA immunosuppressive microenvironment, guide the selection of chemotherapeutic drugs and immunotherapy, and predict the prognosis of patients.

The Application Effect of Traditional Chinese Medicine Nursing on General Anesthesia Combined with Epidural Anesthesia and Electric Resection for the Treatment of Bladder Cancer and Its Influence on Tumor Markers

Objective

To explore the effects of traditional Chinese medicine nursing on general anesthesia combined with epidural anesthesia and electric resection to treat bladder cancer and its influence on tumor markers.

Methods

A total of 160 patients with non-muscle-invasive bladder cancer who underwent general anesthesia combined with epidural anesthesia and resection were included in this study. The patients were divided into control group (n = 80) and study group (n = 80) according to the random number table method. The control group received hydroxycamptothecin bladder perfusion therapy, and the study group received traditional Chinese medicine nursing combined with hydroxycamptothecin bladder perfusion therapy. The clinical efficacy, three-year cumulative survival rate, and postoperative recurrence rate of the two groups of patients were detected. The levels of tumor markers including vascular endothelial growth factor (VECF) and bladder tumor antigen (BTA) before and after treatment were also tested. The immune function, inflammatory factor levels, and quality of life of the two groups before and after treatment were evaluated.

Results

The total effective rate of the study group (83.75%) was significantly higher than that of the control group (58.75%). After treatment, the serum VEGF and BTA levels, inflammatory factors interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α) levels of the two groups of patients decreased, and the decrease in the study group was more significant than that in the control group (P < 0.05). After treatment, the levels of CD3+, CD4+, and CD4+/CD8+ in the two groups increased (P < 0.05), and the increase in the study group was more significant than that in the control group (P < 0.05). After treatment, the CD8+ levels of the two groups of patients decreased (P < 0.05), and the decrease in the study group was more significant than that in the control group (P < 0.05). After treatment, the quality-of-life scores in both groups increased (P < 0.05), and the increase in the study group was even more significant (P < 0.05).

Conclusion

Traditional Chinese medicine nursing has significant clinical effects on the treatment of bladder cancer with general anesthesia combined with epidural anesthesia and electric resection. It can more effectively prevent the risk of recurrence of bladder cancer after surgery, significantly improve the quality of life, improve immune system function, regulate the levels of VECF and BTA, effectively reduce the level of serum inflammatory factors, inhibit tumor progression, and reduce tumor viability.

Supplementation of Probiotic Butyricicoccus pullicaecorum Mediates Anticancer Effect on Bladder Urothelial Cells by Regulating Butyrate-Responsive Molecular Signatures

In bladder cancer, urothelial carcinoma is the most common histologic subtype, accounting for more than 90% of cases. Pathogenic effects due to the dysbiosis of gut microbiota are localized not only in the colon, but also in regulating bladder cancer distally. Butyrate, a short-chain fatty acid produced by gut microbial metabolism, is mainly studied in colon diseases. Therefore, the resolution of the anti-cancer effects of butyrate-producing microbes on bladder urothelial cells and knowledge of the butyrate-responsive molecules must have clinical significance. Here, we demonstrate a correlation between urothelial cancer of the bladder and Butyricicoccus pullicaecorum. This butyrate-producing microbe or their metabolite, butyrate, mediated anti-cancer effects on bladder urothelial cells by regulating cell cycle, cell growth, apoptosis, and gene expression. For example, a tumor suppressor against urothelial cancer of the bladder, bladder cancer-associated protein, was induced in butyrate-treated HT1376 cells, a human urinary bladder cancer cell line. In conclusion, urothelial cancer of the bladder is a significant health problem. To improve the health of bladder urothelial cells, supplementation of B. pullicaecorum may be necessary and can further regulate butyrate-responsive molecular signatures.

FTIR Spectroscopic Imaging Supports Urine Cytology for Classification of Low- and High-Grade Bladder Carcinoma

Simple Summary

Human urine cytological samples were investigated using Fourier transform infrared spectroscopic imaging in terms of recognition of bladder cancer. The clustering of IR spectra of whole cytological smears revealed very good spectral correlation with normal urothelial cell features. Next, the combination of spectral information derived from unsupervised hierarchical cluster analysis and partial least square discriminant analysis (PLS-DA) classified normal vs. low- and high-grade bladder urothelial carcinoma with sensitivity and specificity of 90–97%.

Abstract

Bladder urothelial carcinoma (BC) is a common, recurrent, life-threatening, and unpredictable disease which is difficult to diagnose. These features make it one of the costliest malignancies. Although many possible diagnostic methods are available, molecular heterogeneity and difficulties in cytological or histological examination induce an urgent need to improve diagnostic techniques. Herein, we applied Fourier transform infrared spectroscopy in imaging mode (FTIR) to investigate patients’ cytology samples assigned to normal (N), low-grade (LG) and high-grade (HG) BC. With unsupervised hierarchical cluster analysis (UHCA) and hematoxylin-eosin (HE) staining, we observed a correlation between N cell types and morphology. High-glycogen superficial (umbrella) and low-glycogen piriform urothelial cells, both with normal morphology, were observed. Based on the spectra derived from UHCA, principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were performed, indicating a variation of protein content between the patient groups. Moreover, BC spectral cytology identified a low number of high-glycogen cells for which a shift of the carbohydrate/phosphate bands was also observed. Despite high cellular heterogeneity, PLS-DA was able to classify the spectra obtained. The voided urine FTIR cytology is one of the options that might be helpful in BC diagnosis, as high sensitivity and specificity up to 97% were determined.

HMMR is a downstream target of FOXM1 in enhancing proliferation and partial epithelial-to-mesenchymal transition of bladder cancer cells

Our previous that HMMR upregulation independently predicts poor survival in patients with papillary muscle-invasive bladder cancer (MIBC). In this study, we explored its downstream regulations and the potential transcriptional factors activating its expression. MIBC derived T24 cells, and non-MIBC (NMIBC) derived RT4 cells were used for in vitro and in vivo studies. HMMR expression enhanced cell proliferation, the expression of mesenchymal markers, and cell invasion. It induced the nuclear entry of β-catenin, increased its active form in the nuclear part, and elevated the relative TOP/FOP activity. The promoter region of HMMR has a canonical FKH motif. FOXM1 bound to this site and activated HMMR transcription. HMMR knockdown significantly weakened FOXM1 overexpression induced bladder cancer growth, invasion, partial epithelial-to-mesenchymal transition (pEMT), as well as the activation of the Wnt/β-catenin signaling pathway. In conclusion, the findings in this study expanded our understanding of the mechanisms underlying HMMR dysregulation and the functional role of the FOXM1-HMMR axis in bladder cancer.

Identification of a Novel Ferroptosis-Related Gene Prognostic Signature in Bladder Cancer

Background

Ferroptosis is a newly found non-apoptotic forms of cell death that plays an important role in tumors. However, the prognostic value of ferroptosis-related genes (FRG) in bladder cancer (BLCA) have not been well examined.

Methods

FRG data and clinical information were collected from The Cancer Genome Atlas (TCGA). Then, significantly different FRGs were investigated by functional enrichment analyses. The prognostic FRG signature was identified by univariate cox regression and least absolute shrinkage and selection operator (LASSO) analysis, which was validated in TCGA cohort and Gene Expression Omnibus (GEO) cohort. Subsequently, the nomogram integrating risk scores and clinical parameters were established and evaluated. Additionally, Gene Set Enrichment Analyses (GSEA) was performed to explore the potential molecular mechanisms underlying our prognostic FRG signature. Finally, the expression of three key FRGs was verified in clinical specimens.

Results

Thirty-two significantly different FRGs were identified from TCGA–BLCA cohort. Enrichment analyses showed that these genes were mainly related to the ferroptosis. Seven genes (TFRC, G6PD, SLC38A1, ZEB1, SCD, SRC, and PRDX6) were then identified to develop a prognostic signature. The Kaplan–Meier analysis confirmed the predictive value of the signature for overall survival (OS) in both TCGA and GEO cohort. A nomogram integrating age and risk scores was established and demonstrated high predictive accuracy, which was validated through calibration curves and receiver operating characteristic (ROC) curve [area under the curve (AUC) = 0.690]. GSEA showed that molecular alteration in the high- or low-risk group was closely associated with ferroptosis. Finally, experimental results confirmed the expression of SCD, SRC, and PRDX6 in BLCA.

Conclusion

Herein, we identified a novel FRG prognostic signature that maybe involved in BLCA. It showed high values in predicting OS, and targeting these FRGs may be an alternative for BLCA treatment. Further experimental studies are warranted to uncover the mechanisms that these FRGs mediate BLCA progression.

Circular RNA_0001495 increases Robo1 expression by sponging microRNA-527 to promote the proliferation, migration and invasion of bladder cancer cells

Bladder cancer (BCa) is a heterogeneous disease that poses great threats on public health. Increasing studies have identified the vital functions of circular RNAs (circRNAs) in BCa treatment. Hence, this current study set out to explore the modulatory role of circ_0001495 in BCa development. First, the expression of circ_0001495 was determined by reverse transcription quantitative polymerase chain reaction. Cell biological processes were then analyzed after altering the circ_0001495 expression in T24 cells. Next, interactions among circ_0001495, microRNA-527 (miR-527) and roundabout guidance receptor 1 (Robo1) were investigated by dual luciferase reporter gene assay, RNA pull down assay and FISH assay. Lastly, xenograft tumors in nude mice were established to explore the effect of circ_0001495 in vivo. It was found that circ_0001495 was highly expressed in BCa tissues and cells, and was further correlated with poor prognosis in BCa patients. In addition, circ_0001495 inhibited the activity of miR-527 by acting as a sponge to sponge miR-527, which further elevated the Robo1 expression. Lastly, circ_0001495 was found to promote the proliferation, migration and invasion of BCa cells in vitro through the miR-527/Robo1 axis and promote the growth and metastasis of BCa tumors in vivo. Altogether, findings in our study highlight the promoting role of circ_0001495 in the progression of BCa by increasing Robo1 via sponging miR-527, representing a promising target for BCa management.

TDO2 overexpression correlates with poor prognosis, cancer stemness, and resistance to cetuximab in bladder cancer

Background

Bladder cancer (BC) is the 10th most common cancer in the world. BC with muscle invasion results in a poor prognosis and is usually fatal. Cancer cell metabolism has an essential role in the development and progression of tumors. Expression of tryptophan 2,3‐dioxygenase (TDO2) is associated with tumor progression and worse survival in some other cancers. However, no studies have been performed to uncover the biofunctional roles of TDO2 in BC.

Aim

This study aim to investigate the clinicopathologic significance of TDO2 in BC.

Methods and results

TDO2 expression was evaluated by qRT‐PCR and immunohistochemistry in an integrated analysis with the Cancer Genome Atlas (TCGA) and other published datasets. TDO2 overexpression was significantly associated with T classification, N classification, and M classification, tumor stage, recurrence, and basal type, and with the expression of CD44 and aldehyde dehydrogenase 1 (ALDH1) in BC. High TDO2 expression correlated with poor outcome of BC patients. Using BC cell lines with knockdown and forced expression of TDO2, we found that TDO2 was involved in the growth, migration, and invasiveness of BC cells. Moreover, TDO2 was found to be crucial for spheroid formation in BC cells. Importantly, TDO2 promoted BC cells resistance to cetuximab through integration of the EGFR pathway.

Conclusion

Our results indicate that TDO2 might take an essential part in BC progression and could be a potential marker for targeted therapy in BC.

Pan-cancer analysis of the prognostic value of C12orf75 based on data mining

The differential expression of chromosome 12 open reading frame 75 (C12orf75) is closely related with cancer progression. Here, we studied the expression levels of C12orf75 and investigated its prognostic value in various cancers across distinct datasets including ONCOMINE, PrognoScan, GEPIA, and TCGA. The correlation between genetic alteration of C12orf75 and immune infiltration was investigated using the cBioPortal and TIMER databases. RNA interference was used to verify the influence of C12orf75 knockdown on the biological phenotype of hepatocellular carcinoma cells. C12orf75 showed increased expression in most tested human cancers. The increased expression of C12orf75 was related with a poor prognosis in urothelial bladder carcinoma and hepatocellular liver carcinoma, but it was surprisingly converse in renal papillary cell carcinoma. In urothelial bladder carcinoma and hepatocellular liver carcinoma, we observed positive correlations between the expression of C12orf75 and the infiltration of immune cells, including B cells, CD8+ T cells, CD4+ T cells, macrophages, neutrophils, and dendritic cells. The knockdown of C12orf75 in hepatocellular carcinoma cells suppressed the proliferation, migration, and invasion and arrested the cell cycle. This is the first report C12orf75 has potential as a prognostic biomarker and therapeutic target for molecularly targeted drugs in urothelial bladder carcinoma, hepatocellular liver carcinoma, and renal papillary cell carcinoma.

Substaging of pT1 Urothelial Bladder Carcinoma Predicts Tumor Progression and Overall Survival

INTRODUCTION

Limitations in tumor staging and the heterogeneous natural evolution of pT1 urothelial bladder carcinoma (UBC) make the choice of treatment challenging. We evaluated if histopathological substaging (pT1a, pT1b, and pT1c) helps predict disease recurrence, progression, and overall survival following transurethral resection of the bladder (TURB).

METHODS

We included 239 consecutive patients diagnosed with pT1 UBC at TURB in a single institution since 2001. Each sample was interpreted by our specialized uropathologists trained to subclassify pT1 stage. Three groups were distinguished according to the degree of invasion: T1a (up to the muscularis mucosae [MM]), T1b (into the MM), and T1c (beyond the MM).

RESULTS

T1 substaging was possible in 217/239 (90%) patients. pT1a, b, and c occurred in 124 (57), 59 (27), and 34 (16%), respectively. The median follow-up was 3.1 years, with a cumulative recurrence rate of 52%, progression rate of 20%, and survival rate of 54%. Recurrence was not significantly associated with tumor substage (p = 0.61). However, the Kaplan-Meier survival analysis showed a significantly higher progression rate among T1b (31) and T1c (26%) tumors than T1a (13%) (log-rank test: p = 0.001) stages. In a multivariable model including gender, age, ASA score, smoking, tumor grade, and presence of carcinoma in situ, T1 substage was the single variable significantly associated with progression-free survival (HR 1.7, p = 0.005). Nineteen patients (9%) needed radical cystectomy; among them, 12/19 (63%) had an invasive tumor. Overall survival was significantly associated with tumor substaging (p = 0.001).

CONCLUSION

Histopathological substaging of pT1 UBC is significantly associated with tumor progression and overall survival and therefore appears to be a useful prognostic tool to counsel patients about treatment options.

In Vitro Spectroscopy-Based Profiling of Urothelial Carcinoma: A Fourier Transform Infrared and Raman Imaging Study

Simple Summary

The mortality and recurrence associated with urothelial carcinoma are high. High heterogeneity makes it hard to detect with currently available methods such as cytology and histology. We propose here vibrational spectroscopic imaging as an additional diagnostic tool for the classification of bladder cancer. Our study revealed that chemism-induced spectroscopic features of the cancer cells of various stages and invasiveness were specifically detected.

Abstract

Markers of bladder cancer cells remain elusive, which is a major cause of the low recognition of this malignant neoplasm and its recurrence. This implies an urgent need for additional diagnostic tools which are based on the identification of the chemism of bladder cancer. In this study, we employed label-free techniques of molecular imaging—Fourier Transform Infrared and Raman spectroscopic imaging—to investigate bladder cancer cell lines of various invasiveness (T24a, T24p, HT-1376, and J82). The urothelial HCV-29 cell line was the healthy control. Specific biomolecules discriminated spatial distribution of the nucleus and cytoplasm and indicated the presence of lipid bodies and graininess in some cell lines. The most prominent discriminators are the total content of lipids and sugar moieties as well as the presence of glycogen and other carbohydrates, un/saturated lipids, cytochromes, and a level of S-S bridges in proteins. The combination of the obtained hyperspectral database and chemometric methods showed a clear differentiation of each cell line at the level of the nuclei and cytoplasm and pointed out spectral signals which differentiated bladder cancer cells. Registered spectral markers correlated with biochemical composition changes can be associated with pathogenesis and potentially used for the diagnosis of bladder cancer and response to experimental therapies.

The therapeutic and prognostic implications of molecular biomarkers in urothelial carcinoma

Urothelial cell carcinoma (UCC) of the bladder and upper urinary tract is a heterogeneous disease with distinct biologic features resulting in different clinical behaviors. Bladder cancer (BC) is classified into non-muscle invasive BC (NMIBC) and muscle invasive BC (MIBC). NMIBC is associated with high recurrence rates and risk of progression to invasive disease, whereas MIBC is complicated by systemic recurrence after radical cystectomy because of the limited efficacy of available therapies. UCC of the upper urinary tract (UUT-UCC) is a rare but aggressive urologic cancer characterized by multifocality, local recurrence, and metastasis. Conventional histopathologic evaluation of UCC, including tumor stage and grade, cannot accurately predict the behavior of BC and UUT-UCC. Recent clinical and preclinical studies aimed at understanding the molecular landscape of UCC have provided insight into molecular subtyping, inter- or intratumoral heterogeneity, and potential therapeutic targets. Combined analysis of molecular markers and standard pathological features may improve risk stratification and help monitor tumor progression and treatment response, ultimately improving patient outcomes. This review discusses prognostic and therapeutic biomarkers for BC and UUT-UCC, and describes recent advances in molecular stratification that may guide prognosis, patient stratification, and treatment selection.

Pathological and Survival Outcomes Associated with Variant Histology Bladder Cancers Managed by Cystectomy with or without Neoadjuvant Chemotherapy

PURPOSE

Although neoadjuvant chemotherapy is associated with a survival advantage in pure urothelial, muscle invasive bladder cancer, the role of neoadjuvant chemotherapy is less clear in variant histology or urothelial carcinoma with divergent differentiation. We compared chemotherapy response and survival outcomes of patients with nonpure urothelial carcinoma histology who were managed with neoadjuvant chemotherapy followed by cystectomy vs cystectomy alone.

MATERIALS AND METHODS

We analyzed 768 patients with clinical muscle invasive bladder cancer (cT2-4N0M0) who were treated with cystectomy at a tertiary care center from 2007 to 2017. Patients were stratified by histology and treatment strategy. Adjusted logistic and Cox regression models were used to evaluate pathological downstaging, cancer specific survival and overall survival.

RESULTS

The cohort consisted of 410 patients (53%) with pure urothelial carcinoma, 185 (24%) with urothelial carcinoma with divergent differentiation and 173 (23%) with variant histology. Overall, 314 patients (41%) received neoadjuvant chemotherapy prior to cystectomy. There were similar rates of complete (18% to 30%) and partial (37% to 46%) pathological downstaging with neoadjuvant chemotherapy across all histological subgroups (p=0.30 and p=0.40, respectively). However, while patients with pure urothelial carcinoma experienced an overall survival benefit (HR 0.71, 95% CI 0.51-0.98, p=0.0013) and those with variant histology experienced a cancer specific survival benefit (HR 0.55, 95% CI 0.30-0.99, p=0.0495) with neoadjuvant chemotherapy, patients with urothelial carcinoma with divergent differentiation did not experience overall or cancer specific survival benefits with the use of neoadjuvant chemotherapy prior to cystectomy.

CONCLUSIONS

Among patients with muscle invasive bladder cancer those with nonpure urothelial carcinoma histology with variant histology achieved nearly equivalent response rates and survival benefits with the use of neoadjuvant chemotherapy as those with pure urothelial carcinoma, while patients with urothelial carcinoma with divergent differentiation experienced significantly worse survival outcomes regardless of the use of neoadjuvant chemotherapy prior to cystectomy.

Bladder Cancer Involving Smooth Muscle of Indeterminate Type or Muscularis Mucosae in Transurethral Biopsy Specimens

OBJECTIVES

Bladder cancers invading the muscularis mucosae (MM) are treated differently from those invading the muscularis propria (MP). However, it may be difficult to determine the type of smooth muscle in transurethral resection (TUR) or biopsy specimens. We aimed to investigate the clinicopathologic features of bladder cancers involving smooth muscle of indeterminate type (SMIT) in TUR specimens in comparison with those invading the MM.

METHODS

We identified 103 patients with bladder cancer involving SMIT (n = 27) or the MM (n = 76) in TUR specimens. All patients underwent subsequent restaging TUR or cystectomy.

RESULTS

Bladder cancer with SMIT invasion showed a significantly higher rate of MP invasion in the subsequent specimens than those invading the MM (52% vs 29%). Lack of MP in the TUR specimens had a significantly higher risk of MP invasion in the subsequent specimens than those with the MP (61% vs 40%). The overall survival time for patients with SMIT invasion was significantly shorter than those with MM invasion.

CONCLUSIONS

Bladder cancers with SMIT invasion in TUR specimens show more frequent cancer upstaging in the subsequent specimens and a poorer clinical outcome than those invading the MM, which highlights the importance of a cancer restaging procedure for these patients.

Assessment of Luminal and Basal Phenotypes in Bladder Cancer

Genomic profiling studies have demonstrated that bladder cancer can be divided into two molecular subtypes referred to as luminal and basal with distinct clinical behaviors and sensitivities to frontline chemotherapy. We analyzed the mRNA expressions of signature luminal and basal genes in bladder cancer tumor samples from publicly available and MD Anderson Cancer Center cohorts. We developed a quantitative classifier referred to as basal to luminal transition (BLT) score which identified the molecular subtypes of bladder cancer with 80–94% sensitivity and 83–93% specificity. In order to facilitate molecular subtyping of bladder cancer in primary care centers, we analyzed the protein expressions of signature luminal (GATA3) and basal (KRT5/6) markers by immunohistochemistry, which identified molecular subtypes in over 80% of the cases. In conclusion, we provide a tool for assessment of molecular subtypes of bladder cancer in routine clinical practice.

Micropapillary urothelial carcinoma of urinary bladder displays immunophenotypic features of luminal and p53-like subtypes and is not a variant of adenocarcinoma

OBJECTIVES

Micropapillary urothelial carcinoma of the urinary bladder (MPUC) is a rare variant of urothelial carcinoma which has aggressive clinical characteristics. The objective is to investigate the molecular subtypes of MPUC and the impact to the clinical outcome and determine whether MPUC represents a variant of adenocarcinoma.

MATERIALS AND METHODS

We evaluated surrogate immunohistochemical markers of luminal, basal, and p53-like subtypes and correlated with prognosis and the expression of markers related to bladder adenocarcinoma and glandular differentiation in 56 cases of MPUC (10 cases of transurethral resection and 46 cases of radical cystectomy). Biomarker expression in co-existing conventional urothelial carcinoma was also analyzed. Cox regression analysis was performed to study the impact of molecular subtype on the clinical outcome.

RESULTS

Thirty-four cases (61%) met criteria for the luminal subtype. Twenty-two cases (39%) displayed a p53-like subtype. In contrast, 40/56 (71%) cases of coexisting conventional urothelial carcinoma were classified as luminal subtype and 16/56 (29%) cases were designated as p53-like subtype. There was no significant survival difference between luminal subtype and p53-like subtype. CDX2, villin, and cadherin 17 were negative in all cases. MUC1 was strongly and diffusely expressed in the stroma-facing surface of MPUC tumor cells in all the cases.

CONCLUSIONS

Our findings suggest that MPUC possesses characteristics of luminal and p53-like subtypes, and does not harbor phenotypic features of the basal subtype. There is no significant difference in the prognosis between luminal and p53-like subtype MPUC. MPUC is not a variant of adenocarcinoma and does not represent a form of glandular differentiation, in contrast to other organ sites.

Systematic screening of protein-coding gene expression identified HMMR as a potential independent indicator of unfavorable survival in patients with papillary muscle-invasive bladder cancer

Papillary and non-papillary are two histological patterns of bladder carcinogenesis and are considered as dual-track oncogenic pathways, which have different genetic alterations. The TCGA-bladder cancer (BLCA) database contains clinicopathological, genomic and survival data from over 400 muscle-invasive bladder cancer patients. In this study, using data from this database, we performed a systematic screening of gene expression to identify the protein-coding gene that might have prognostic value in papillary and non-papillary muscle-invasive bladder cancer (MIBC). The data of patients with primary MIBC in TCGA-BLCA was acquired from the UCSC Xena project (http://xena.ucsc.edu) for re-analysis. By setting |log2 fold change|≥2 and adjusted p value <0.01 as the screening criteria, we found 751 significantly dysregulated genes, including 183 overexpressed and 568 downregulated genes. HMMR was identified as a potential prognostic marker with unique expression. Multivariate analysis showed that its expression was an independent prognostic indicator of shorter progression-free survival (PFS) (HR: 1.400, 95%CI: 1.021-1.920, p = 0.037) in the papillary subtype. ENST00000393915.8 and ENST00000358715.3, two transcripts that contain all 18 exons and encode the full length of HMMR, were significantly upregulated in cancer tissues compared with normal bladder tissues. None of the 17 CpG sites in its DNA locus was relevant to HMMR expression. 26/403 (6.5%) MIBC cases had HMMR gene-level amplification, which was associated with upregulated HMMR expression compared with the copy-neutral and deletion groups. Gene set enrichment analysis (GSEA) in papillary MIBC found that the high HMMR expression group was associated with upregulated genes enriched in multiple gene sets with well-established role in BC development, including G2M checkpoint, E2 F Targets, Myc Targets V1, Myc Targets V2 and Glycolysis. Based on these findings, we infer that HMMR expression might be a specific prognostic marker in terms of PFS in papillary MIBC. DNA amplification might be an important mechanism of its elevation.

Predicting outcomes in non-muscle invasive (Ta/T1) bladder cancer: the role of molecular grade based on luminal/basal phenotype

Bladder cancer tumors can be divided into two molecular subtypes referred to as luminal or basal. Each subtype may react differently to current chemotherapy or immunotherapy. Likewise, the technology required for comprehensive molecular analysis is expensive and not yet applicable for routine clinical diagnostics. Therefore, it has been suggested that the immunohistochemical expressions of only two markers, luminal (CK20+, CK5/6-) and basal (CK5/6+, CK20-), is sufficient to identify the molecular subtypes of bladder cancer. This would represent a molecular grade that could be used in daily practice. Molecular classification is done using immunohistochemistry to assess luminal-basal phenotype based on tissular expression of CK20 and CK5/6 as surrogate for luminal or basal subtypes, respectively. A series of 147 non-muscle-invasive bladder carcinoma cases was selected, and the tumors were divided into four subgroups based on the presence of CK20 and/or CK5/6, that is, null (CK20-, CK5/6-), mixed (CK20+, CK5/6+), basal (CK20-, CK5/6+), and luminal (CK20+, CK5/6-) categories. Survival analysis was estimated using the Kaplan-Meier method and the log-rank test. Hazard ratios were calculated by Cox multivariate analysis. The molecular grade included cases with null (n = 89), mixed (n = 6), basal (n = 20), and luminal (n = 32) phenotypes with differences in recurrence-free, progression-free and cancer-specific survival associated with molecular-grade categories in patients with low- or high-grade Ta, or high-grade T1 tumors. The multivariate analysis identified the luminal phenotype as a predictor of more aggressive neoplasms. Our findings provide a rationale to investigate luminal and basal subtypes of bladder cancer using two gene expression signatures as surrogate markers and show that non-muscle-invasive bladder carcinoma can be stratified into biologically and clinically different subgroups by using an immunohistochemical classifier.