A quantitative polymerase chain reaction based method for molecular subtype classification of urinary bladder cancer-Stromal gene expressions show higher prognostic values than intrinsic tumor genes.

Transcriptome-based molecular subtypes of muscle-invasive bladder cancer (MIBC) have been shown to be both prognostic and predictive, but are not used in routine clinical practice. We aimed to develop a feasible, reverse transcription quantitative polymerase chain reaction (RT-qPCR)-based method for molecular subtyping. First, we defined a 68-gene set covering tumor intrinsic (luminal, basal, squamous, neuronal, epithelial-to-mesenchymal, in situ carcinoma) and stromal (immune, extracellular matrix, p53-like) signatures. Then, classifier methods with this 68-gene panel were developed in silico and validated on public data sets with available subtype class information (MD Anderson [MDA], The Cancer Genome Atlas [TCGA], Lund, Consensus). Finally, expression of the selected 68 genes was determined in 104 frozen tissue samples of our MIBC cohort by RT-qPCR using the TaqMan Array Card platform and samples were classified by our newly developed classifiers. The prognostic value of each subtype classification system and molecular signature scores were assessed. We found that the reduced marker set combined with the developed classifiers were able to reproduce the TCGA II, MDA, Lund and Consensus subtype classification systems with an overlap of 79%, 76%, 69% and 64%, respectively. Importantly, we could successfully classify 96% (100/104) of our MIBC samples by using RT-qPCR. Neuronal and luminal subtypes and low stromal gene expressions were associated with poor survival. In conclusion, we developed a robust and feasible method for the molecular subtyping according to the TCGA II, MDA, Lund and Consensus classifications. Our results suggest that stromal signatures have a superior prognostic value compared to tumor intrinsic signatures and therefore underline the importance of tumor-stroma interaction during the progression of MIBC.

Identification of an IDO1-based immune classifier for survival prediction of upper tract urothelial carcinoma.

The limited response rate of immunotherapy in upper tract urothelial carcinoma (UTUC) might be attributed to additional immunosuppressive mechanisms in vivo. As a promising immune checkpoint target, the expression and prognostic role of indoleamine 2,3-dioxygenase 1 (IDO1) in UTUC remains unknown. In this study, the expression and prognostic value of IDO1 was analyzed in 251 patients from 3 independent cohorts. The least absolute shrinkage and selection operator (LASSO) Cox regression model was used to construct an IDO1-based immune classifier and external validation was performed to further validate the classifier. RNA sequencing and immunofluorescence were used to explore the immune contexture of different risk groups stratified by classifier. We found that high IDO1 expression on tumor cells (TC) indicated a poorer overall survival and disease-free survival in all cohorts. Patients with high expression of IDO1 TC possessed increased infiltration of CD4+ , CD8+ and Foxp3+ T cells. An immune classifier based on intratumoral CD8+ lymphocytes, IDO1 TC, and stromal PD-L1 expression status was developed, with its area under the curves (AUCs) values for overall survival at 5 y being 0.79 (95% confidence interval [CI] 0.65-0.93) in the discovery cohort, 0.75 (95% CI 0.58-0.92) and 0.78 (95% CI 0.65-0.92) in the internal and external validation cohorts, respectively. The high-risk group stratified by the immune classifier was associated with immunosuppressive contexture, accompanied by enhanced CD8+ T cells exhaustion patterns. Our IDO1-based immune classifier can provide a superior accuracy for survival prediction and lead to individual stratification of UTUC immune subtypes.

Recurrence- and progression-free survival in intermediate-risk non-muscle-invasive bladder cancer: the impact of conditional evaluation and subclassification.

OBJECTIVES: To assess the change in rates of recurrence-free survival (RFS) and progression-free survival (PFS) based on the duration of survival without recurrence or progression among patients with intermediate-risk (IR) non-muscle-invasive bladder cancer (NMIBC), and to examine the predictive factors for recurrence at different time points by assessing conditional RFS and PFS. PARTICIPANTS AND METHODS: A cohort of 602 patients treated with transurethral resection of bladder tumour and histopathologically diagnosed with IR NMIBC was included in this retrospective study. RESULTS: The conditional RFS rate at 1, 2, 3, 4 and 5 years improved with increased duration of RFS; however, the conditional PFS rate did not improve over time. Multivariable analyses showed that recurrent tumour, multiple tumours, tumour size (>3 cm), immediate postoperative instillation of chemotherapy, and administration of BCG were independent predictive factors for recurrence at baseline. The predictive ability of these factors disappeared with increasing recurrence-free survivorship. Subclassification of these patients with IR NMIBC into three groups using clinicopathological factors (recurrent tumour, multiple tumours, tumour size) demonstrated that the high IR group (two factors) had significantly worse RFS than the intermediate (one factor, P < 0.001) and low IR groups (no factor, P = 0.005) at baseline. This subclassification stratified conditional risk of RFS also at 1, 3 and 5 years, which provides the basis for distinct surveillance protocols among patients with IR NMIBC. CONCLUSION: Conditional survival analyses of patients with IR NMIBC demonstrate that RFS changes over time, while PFS does not change. These data support distinct surveillance protocols based on the subclassification of IR NMIBC.

Combining two grading systems: the clinical validity and inter-observer variability of the 1973 and 2004 WHO bladder cancer classification systems assessed in a UK cohort with 15 years of prospective follow-up.

PURPOSE: Paucity of reliable long-term data on the prognostic implications of the 2004 WHO bladder cancer classification system necessitates utilisation of both this and the 1973 grading systems. This study evaluated, in noninvasive (pTa) bladder tumours, the prognostic value of the 2004 system independently and in combination with the 1973 system while establishing concordance between tertiary centre uropathologists. METHODS: We used a cohort of non-muscle invasive bladder cancer (NMIBC) patients diagnosed between 1991 and 93 where tumour features were gathered prospectively with detailed cystoscopic follow-up data recorded over 15 years. Initial grading was by one senior expert uropathologist (UP1) using the 1973 WHO classification alone. Subsequently, two other expert uropathologists (UP2 and UP3), blinded to the previous grading, re-evaluated the pathology slides and graded the tumours using both the 1973 and 2004 systems. Association between grade and recurrence/progression was analysed and the Cohen Kappa test assessed concordance between pathologists. RESULTS: Of 370 new NMIBC, 229 were staged noninvasive (pTa). Recurrence rates were 46.2% and 50.0% for LGPUC (low-grade papillary urothelial carcinoma) and HGPUC (high-grade papillary urothelial carcinoma), respectively, while progression was seen in 3.9% and 10.0% of LGPUC and HGPUC, respectively. Concordance between uropathologists UP2 and UP3 for the 2004 and 1973 systems was good (Kappa = 0.69) and fair (Kappa = 0.25), respectively. CONCLUSIONS: With good inter-observer concordance, the 2004 WHO classification system of noninvasive bladder tumours appears to accurately predict recurrence and progression risks. The combination of both grading systems to low-grade tumours allows further refinement of the natural history.

Prognostic impact of molecular muscle-invasive bladder cancer subtyping approaches and correlations with variant histology in a population-based mono-institutional cystectomy cohort.

PURPOSE: Recently discovered molecular classifications for urothelial bladder cancer appeared to be promising prognostic and predictive biomarkers. The present study was conducted to evaluate the prognostic impact of molecular subtypes assessed by two different methodologies (gene and protein expression), to compare these two approaches and to correlate molecular with histological subtypes in a consecutively collected, mono-institutional muscle-invasive bladder cancer (MIBC) cohort. METHODS: 193 MIBC were pathologically re-evaluated and molecular subtypes were assessed on mRNA (NanoString technology, modified 21-gene-containing MDACC approach) and protein levels (immuno-histochemical [IHC] analysis of CK5, CK14, CD44, CK20, GATA3 and FOXA1). Descriptive statistical methods and uni-/multi-variable survival models were employed to analyze derived data. RESULTS: Neither gene expression nor protein-based subtyping showed significant associations with disease-specific (DSS) or recurrence-free survival (RFS). Agreement between mRNA (reference) and protein-based subtyping amounted 68.6% for basal, 76.1% for luminal and 50.0% for double-negative tumors. Histological subtypes associated with RFS in uni-variable (P = 0.03), but not in multivariable survival analyses. Tumors with variant histology predominantly showed luminal subtypes (gene expression subtyping: 36/55 cases, 65.5%; protein subtyping: 44/55 cases, 80.0%). Squamous differentiation significantly associated with basal subtypes (gene expression subtyping: 44/45 squamous cases, 97.8%; protein subtyping: 36/45 cases, 80.0%). CONCLUSION: In our consecutive cystectomy cohort, neither gene, protein expression-based subtyping, nor histological subtypes associated with DSS or RFS in multi-variably adjusted survival analyses. Application of a limited IHC subtyping marker panel showed high concordance of 83.9% with gene expression-based subtyping, thus underlining the utility for subtyping in pathological routine diagnostics. In addition, histological MIBC subtypes are strong indicators for intrinsic subtypes.

Utility of pT3 substaging in lymph node-negative urothelial carcinoma of the bladder: do pathologic parameters add to prognostic sub-stratification?

PURPOSE: The value of bladder cancer (BC) substaging into macroscopic (pT3b) and microscopic (pT3a) perivesical fat extension in lymph node (Ln)-negative patients is controversially discussed and limited evidence for prognostic relevance of additional histopathological factors in pT3 BC exists. We evaluated the prognostic value of pT3 substaging and established pathological and clinical parameters with focus on tumor invasive front (TIF) and tumor size. METHODS: Specimens of 52 patients treated with radical cystectomy (RC) for pT3 a/b muscle-invasive BC were reviewed and re-evaluated by a pathologist specialized in uropathology. Clinical variables and standard histopathologic characteristics were assessed including TIF and tumor size. Their value as prognosticators for overall survival (OS) and recurrence-free survival (RFS) was evaluated. RESULTS: Mean age of patients was 67.55 years. Tumors were staged pT3a in 28 patients (53.8%) and pT3b in 24 (46.8%). Median OS was 34.51 months. Median tumor size was 3.2 cm, median TIF was 11.0 mm. Differences in OS between pT3a and pT3b were not significant (p = 0.45). Carcinoma in situ (CIS) and lymphovascular invasion (LVI) were significantly associated with pT3b tumors. Univariate analysis could not identify pathological prognosticators like TIF or tumor size for OS and RFS (p for all > 0.05). CONCLUSION: No significant differences in OS or RFS were observed comparing Ln-negative pT3 BC following radical cystectomy. Additional pathologic variables like TIF could not be identified as prognosticator. Relevance of pT3 BC substaging needs reevaluation in larger prospective cohorts.

Impact of immunohistochemistry-based molecular subtype on predicting chemotherapy response and survival in patients with T1 stage bladder cancer after bladder-preserving treatment.

OBJECTIVE: To explore the immunohistochemistry-based molecular subtypes of bladder cancer, and their impact on the prognosis and the chemotherapy response between gemcitabine plus cisplatin intra-arterial chemotherapy and epirubicin-inducted intravesical chemotherapy, in patients with T1 stage bladder cancer after bladder-preserving treatment. METHODS: One hundred and seventy-six patients with T1 stage bladder cancer were selected for this study. Thirty-three patients underwent radical cystectomy, 43 received gemcitabine plus cisplatin intra-arterial chemotherapy and 100 received intravesical chemotherapy. The markers labeled with luminal (GATA3, Uroplakin II, CK20) and basal (CK5/6, CK14, CD44) phenotypes were chosen as candidate markers. RESULTS: One hundred and seventy-six patients were divided into 76 patients as basal/squamous (BASQ), 45 as the luminal A and 55 as the luminal B. Compared with the luminal B and BASQ tumors, the luminal A tumors showed a trend for better recurrence-free survival (P = 0.105) and progression-free survival (P = 0.093). The combination of CK20 and GATA3 was practical to identify the molecular phenotypes with total 84.9% accuracy and significantly associated with recurrence-free survival (P = 0.025) and progression-free survival (P = 0.004). The patient with BASQ tumors who received intravesical chemotherapy showed a trend for worse progression-free survival than the patient who received gemcitabine plus cisplatin intra-arterial chemotherapy or radical cystectomy. Furthermore, the patients with BASQ tumors experienced a significant improvement in progression-free survival after gemcitabine plus cisplatin intra-arterial chemotherapy compared with the patients who received intravesical chemotherapy (P = 0.011). CONCLUSIONS: The immunohistochemistry-based molecular subtypes could predict the patient's prognosis and clinically different chemotherapeutic survival outcomes in patients with T1 stage bladder cancer after bladder-preserving treatment.

Construction of Decision Trees Based on Gene Expression Omnibus Data to Classify Bladder Cancer and Its Subtypes.

BACKGROUND Bladder cancer is a malignant tumor of the genitourinary system. Different subtypes of bladder cancer have different treatment methods and prognoses. Therefore, identifying hub genes affecting other genes is of great significance for the treatment of bladder cancer. MATERIAL AND METHODS We obtained expression profiles from the GSE13507 and GSE77952 datasets from the Gene Expression Omnibus database. First, principal component analysis was used to identify the difference in gene expression in different types of tissues. Differential expression analysis was used to find the differentially expressed genes between normal and tumor tissues, and between tumors with and without muscle infiltration. Further, based on differentially expressed genes, we constructed 2 decision trees for differentiating between tumor and normal tissues, and between muscle-infiltrating and non-muscle-infiltrating tumor tissues. A receiver operating characteristic curve was used to evaluate the prediction effect of the decision trees. RESULTS FAM107A and C8orf4 showed significantly lower expression in bladder cancer tissues than in normal tissues. Regarding muscle infiltration, CTHRC1 showed lower expression and HMGCS2 showed higher expression in non-muscle-infiltrating samples than in those with muscle infiltration. We constructed 2 decision trees for differentiating between tumor and normal tissue, and between tissues with and without muscle infiltration. Both decision trees showed good prediction results. CONCLUSIONS These newly discovered hub genes will be helpful in understanding the occurrence and development of different subtypes of bladder cancer, and will provide new therapeutic targets and biomarkers for bladder cancer.

Defining muscle-invasive bladder cancer immunotypes by introducing tumor mutation burden, CD8+ T cells, and molecular subtypes.

Immunotherapy, especially anti-PD-1, is becoming a pillar of modern muscle-invasive bladder cancer (MIBC) treatment. However, the objective response rates (ORR) are relatively low due to the lack of precise biomarkers to select patients. Herein, the molecular subtype, tumor mutation burden (TMB), and CD8+ T cells were calculated by the gene expression and mutation profiles of MIBC patients. MIBC immunotypes were constructed using clustering analysis based on tumor mutation burden, CD8+ T cells, and molecular subtypes. Mutated genes, enriched functional KEGG pathways and GO terms, and co-expressed network-specific hub genes have been identified. We demonstrated that ORR of immunotype A patients identified by molecular subtype, CD8+ T cells, and TMB is about 36% predictable. PIK3CA, RB1, FGFR3, KMT2C, MACF1, RYR2, and EP300 are differentially mutated among three immunotypes. Pathways such as ECM-receptor interaction, PI3K-Akt signaling pathway, and TGF-beta signaling pathway are top-ranked in enrichment analysis. Low expression of ACTA2 was associated with the MIBC survival benefit. The current study constructs a model that could identify suitable MIBC patients for immunotherapy, and it is an important step forward to the personalized treatment of bladder cancers.

Comprehensive Gene Expression Analyses of Immunohistochemically Defined Subgroups of Muscle-Invasive Urinary Bladder Urothelial Carcinoma.

A number of urinary bladder urothelial carcinoma (UB UC) mRNA-based classification systems have been reported. It also has been observed that treatment response and prognosis are different for each molecular subtype. In this study, cytokeratin (CK)5/6 and CK20 immunohistochemistry (IHC) were performed, and IHC-based subgroup classification was applied. UB UC was classified into CK5/6 single-positive (SP), CK20 SP, double-positive (DP) and double-negative (DN) subgroups, and transcriptional analysis was performed. The results of gene ontology (GO) terms and functional analysis using differentially expressed genes indicate that, CK5/6 SP and DP subgroups were enriched in cell migration, immune activation, interleukin 6-Janus kinase-signal transducer and activator of transcription 3 (IL6-JAK-STAT3) signaling pathway and tumor necrosis factor-α signaling via the nuclear factor-κB (NF-κB) signaling pathway signature gene. In addition, compared with the other subgroups, the DN subgroup showed inhibited cell movement, cell migration, and cell activation. Furthermore, in survival analysis, the CK5/6 SP subgroup was significantly associated with poor progression-free survival (p = 0.008). The results of our study indicate that the CK5/6 positive subgroup exhibited high gene expression signature related to aggressive behavior and exhibited worse clinical outcome.

A Genomic Classifier for Predicting Clinically Aggressive Luminal Bladder Tumors with Higher Rates of Pathological Up Staging.

PURPOSE: Urothelial carcinoma of the luminal molecular subtype is associated with lower rates of pathological up staging from clinical stage T1-T2 to nonorgan confined (pT3 or greater and/or pN+) disease at radical cystectomy. However, approximately a third of luminal urothelial carcinoma cases were up staged to nonorgan confined disease, and these may be under treated if neoadjuvant chemotherapy is withheld. In this study we trained a genomic classifier to predict luminal nonorgan confined disease in patients diagnosed with clinically organ confined (cT1/T2) disease. MATERIALS AND METHODS: Specimens from transurethral resected high grade cT1-T2N0M0 urothelial carcinoma of the bladder that belonged to the luminal subtype (Seiler 2017) were randomly split into training (75) and testing (25) sets for the development of a single sample luminal up staging classifier using lasso/ridge-penalized logistic regression. All patients underwent radical cystectomy without neoadjuvant chemotherapy and the primary end point was up staging to nonorgan confined disease. A radical cystectomy cohort and a platinum treated neoadjuvant chemotherapy cohort were used to evaluate the luminal up staging classifier. RESULTS: Up staging to nonorgan confined disease occurred in 34% of luminal cases. The luminal up staging classifier predicted up staging in 32 of 34 cases, with 6 false-positives (AUC 0.96). The sensitivity for detection of luminal pN+ disease was 95% (20 of 21). Patients with predicted nonorgan confined luminal tumors had worse survival than those with organ confined luminal tumors (p=0.001). On multivariable analysis the luminal up staging classifier was a significant predictor of overall survival after adjusting for clinical variables available at transurethral resection. The luminal up staging classifier also predicted overall survival for aggressive luminal TCGA (The Cancer Genome Atlas) cases (n=83, p=0.043). In the neoadjuvant chemotherapy cohort the luminal up staging classifier predicted 9 up staging cases, all of which had excellent prognosis. CONCLUSIONS: A luminal up staging classifier was developed that distinguishes a subset of cT1-T2N0M0 luminal urothelial carcinoma cases at high risk for up staging to nonorgan confined disease at radical cystectomy and of death. Validation of this model in an independent, large patient cohort is necessary to determine how molecular stratification of luminal tumors could be used to guide treatment of these patients.

Updates on the Genomics of Bladder Cancer and Novel Molecular Taxonomy.

Urothelial carcinoma (UC) is the most common malignant neoplasm of the bladder that encompasses a wide spectrum of histopathologic features and various molecular alterations and subtypes, responsible for its significant morphologic and genomic heterogeneity. Morphologically, in addition to classic UC (not otherwise specified), many well documented variant histologies are a common finding in invasive UC, and include squamous, glandular, micropapillary, sarcomatoid, small cell/neuroendocrine, clear cell, lymphoepithelioma-like, and plasmacytoid types, among others. This review provides an update on the recent advances in the molecular characterization and novel molecular taxonomy of UC and variant histologies.

Update on the guideline of guidelines: non-muscle-invasive bladder cancer.

Non-muscle-invasive bladder cancer (NMIBC) is the most common form of bladder cancer, with frequent recurrences and risk of progression. Risk-stratified treatment and surveillance protocols are often used to guide management. In 2017, BJUI reviewed guidelines on NMIBC from four major organizations: the American Urological Association/Society of Urological Oncology, the European Association of Urology, the National Comprehensive Cancer Network, and the National Institute for Health and Care Excellence. The present update will review major changes in the guidelines and broadly summarize new recommendations for treatment of NMIBC in an era of bacillus Calmette-Guérin shortage and immense novel therapy development.

Molecular pathology of the luminal class of urothelial tumors.

Molecular subtypes of urothelial carcinoma may be divided into luminal and nonluminal tumors. Nonluminal tumors are composed of cases with basal/squamous-like or small cell/neuroendocrine features, with a consensus on the molecular characteristics of the respective subtype. In contrast, luminal tumors are more disparate with three to five suggested subtypes and with definitions that do not always cohere. To resolve some of these disparities we assembled a cohort of 344 luminal tumors classified as urothelial-like (Uro), with the subtypes UroA, UroAp, UroB, and UroC, or genomically unstable (GU) according to the LundTax system. Cases were systematically analyzed by immunohistochemistry using antibodies for proteins representing important biological processes or cellular states: KRT5, EGFR, and CDH3 for the integrity of a basal cell layer; CCNB1, Ki67, and FOXM1 for proliferation; FGFR3 and ERBB2 for receptor tyrosine kinase status; CCND1, CDKN2A(p16), RB1, and E2F3 for cell cycle regulation; PPARG, GATA3, and TP63 for the differentiation regulatory system; and KRT20 and UPK3 for the differentiation readout. We show that Uro tumors form one, albeit heterogenous, group characterized by FGFR3, CCND1, and RB1 expression, but low or absence of CDKN2A(p16) and ERBB2 expression. The opposite expression pattern is observed in GU cases. Furthermore, Uro tumors are distinguished from GU tumors by showing a high RB1/p16 expression ratio. Class defining characteristics were independent of pathological stage and growth pattern, and thus intrinsic. In Uro tumors, proliferation was limited to a well-defined single layer of basal-like cells in UroA tumors but occurred throughout the tumor parenchyma, independent of the basal layer, in the more progressed UroAp and UroC tumors. A similar change in proliferation topology was not observed in GU. We conclude that luminal urothelial carcinomas consist, at the molecular pathology level, of two major subtypes, the larger heterogenous Uro and the biologically distinct GU subtype. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Profiles of Immune Infiltration in Bladder Cancer and its Clinical Significance: an Integrative Genomic Analysis.

Tumor-infiltrating immune cells are closely related to the prognosis of bladder cancer. Analysis of tumor infiltrating immune cells is usually based on immunohistochemical analysis. Since many immune cell marker proteins are not specific for different immune cells, which may induce misleading or incomplete. CIBERSORT is an algorithm to estimate specific cell types in a mixed cell population using gene expression data. In this study, the CIBERSORT algorithm was used to identify the immune cell infiltration signatures. The gene expression profiles, mutation data, and clinical data were collected from The Cancer Genome Atlas (TCGA) database. Unsupervised consensus clustering was used to acquire the immune cell infiltration subtypes of bladder cancer based on the fractions of 22 immune cell types. Four immune cell clusters with different immune infiltrate and mutation characteristics were identified. In addition, this stratification has a prognostic relevance, with cluster 2 having the best outcome, cluster 1 the worst. These clusters showed distinct mRNA expression patterns. The characteristic genes in subtype cluster 1 were mainly involved in cell division, those in subtype cluster 2 were mainly related in antigen processing and presentation, those in subtype cluster 3 were mainly involved in epidermal cell differentiation, and those in subtype cluster 4 were mainly related in the humoral immune response. These differences may affect the development of the bladder cancer, the sensitivity to treatment as well as the prognosis. Through further validation, this study may contribute to the development of personalized therapy and precision medical treatments.

Centrosome Protein 78 Is Overexpressed in Muscle-Invasive Bladder Cancer and Is Associated with Tumor Molecular Subtypes and Mutation Signatures.

BACKGROUND Centrosome aberrations have long been linked to tumorigenesis. Centrosome protein 78 (CEP78) is a centrosome component that is required to regulate the cell cycle, but its role in bladder cancer has not been elucidated. MATERIAL AND METHODS Real-time quantitative polymerase chain reaction and immunohistochemistry were used to examine the expression of CEP78 in bladder cancer tissues and adjacent non-cancer tissues. RESULTS Analysis of the RNA-Seq data from the TCGA (The Cancer Genome Atlas) MIBC cohort (n=408) revealed that CEP78 was overexpressed in tumor tissues, which was confirmed with fresh-frozen and formalin-fixed paraffin-embedded specimens collected from 28 and 33 MIBC patients, respectively, in the present study. The clinicopathological relevance of CEP78 was further investigated. High CEP78 expression was found to be correlated with non-papillary histological type, luminal, basal-squamous and neuronal molecular subtypes, TP53 mutation, RB1 mutation, wild-type FGFR3, PPARG fusion and amplification, high total number of single-nucleotide variants, and high neoantigen load, but it was not associated with tumor stages or overall survival. CONCLUSIONS The results of this study suggest that CEP78 plays in a role in promoting the development of MIBC and could be a novel diagnostic and therapeutic target.

Evolution of Urothelial Bladder Cancer in the Context of Molecular Classifications.

Bladder cancer is a heterogeneous disease that is not depicted by current classification systems. It was originally classified into non-muscle invasive and muscle invasive. However, clinically and genetically variable tumors are summarized within both classes. A definition of three groups may better account for the divergence in prognosis and probably also choice of treatment. The first group represents mostly non-invasive tumors that reoccur but do not progress. Contrarily, the second group represent non-muscle invasive tumors that likely progress to the third group, the muscle invasive tumors. High throughput tumor profiling improved our understanding of the biology of bladder cancer. It allows the identification of molecular subtypes, at least three for non-muscle invasive bladder cancer (Class I, Class II and Class III) and six for muscle-invasive bladder cancer (luminal papillary, luminal non-specified, luminal unstable, stroma-rich, basal/squamous and neuroendocrine-like) with distinct clinical and molecular phenotypes. Molecular subtypes can be potentially used to predict the response to treatment (e.g., neoadjuvant chemotherapy and immune checkpoint inhibitors). Moreover, they may allow to characterize the evolution of bladder cancer through different pathways. However, to move towards precision medicine, the understanding of the biological meaning of these molecular subtypes and differences in the composition of cell subpopulations will be mandatory.

Molecular subtyping bladder cancer: Is it ready for clinical practice?

Bladder cancer, one of the more common cancers, is a heterogeneous disease, both morphologically and clinically. Although histological classification and extent of the disease (staging) guide treatment options, the heterogeneity in responses to therapy highlights the need for better stratification of patients for the appropriate therapy in order to achieve better outcomes. Several molecular classifications of muscle-invasive bladder cancer have been proposed but currently their use in clinical practice is limited by the complexity of the methods used and diversity of the subtypes.

Clinical and molecular characteristics of bladder urothelial carcinoma subtypes.

Bladder urothelial carcinoma (BLCA) is a common malignancy with high heterogeneity. A reasonable molecular subtyping can facilitate biological study and personalized therapy of BLCA. In this study, unsupervised consensus clustering was used to acquire the molecular subtypes of BLCA based on messenger RNA (mRNA) and microRNA (miRNA) data. Gene signature markers and canonical signaling pathways were compared between different subtypes. The Database for Annotation, Visualization and Integrated Discovery (DAVID) was used for the functional annotation of overexpressed genes in different subtypes for Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Three molecular subtypes were identified including C1 (luminal-P53 like), C2 (luminal-other), and C3 (basal-immune-squamous). C2 was different from C1 and C3 in clinical characteristics, including younger, better prognosis, and a higher proportion of papillary, Asian, low-grade, early-stage, lymph node negative, and complete remission patients (P < 0.05). Three molecular subtypes also showed distinct mRNA and miRNA expression patterns. luminal and P53-like markers were highly expressed in subtype C1, luminal markers were highly expressed in subtype C2, and basal, EMT/claudin-low, immune and squamous-differentiation markers were highly expressed in subtype C3. In addition, highly expressed genes in C1 were involved in extracellular signal transduction and cell-cell interaction, highly expressed genes in C2 were associated with oxygen transport, energy and steroid metabolism, and highly expressed genes in C3 were related with inflammatory, immune, cytokine, and signal transduction. BLCA in different molecular subtypes showed different clinical and molecular characteristics and personalized therapy needed to be adopted according to the molecular subtypes.

Variants and new entities of bladder cancer.

Pathological evaluation of bladder cancer typically reveals great tumour heterogeneity, and therefore the common observation of urothelial carcinoma exhibiting a wide variety of histopathological patterns is not surprising. Some of these patterns are so distinctive that they have been recognised as specific variants of urothelial carcinoma. Classifications have recently been revised in the 2016 World Health Organisation (WHO) classification of tumours of the urinary system and male genital organs. The current WHO classifications clarify terminological issues and provide better definition criteria, but also incorporate some new entities. Many of these variants have important prognostic or therapeutic implications worth knowing by the urologist and oncologist, but also represent diagnostic challenges in daily pathology practice. This review will discuss the features of variants of urothelial carcinoma in the context of our current clinical practice. Histological variations and new entities of bladder cancer not included in the current WHO classification of urothelial tumours will be briefly discussed.