Molecular biomarkers of progression in non-muscle-invasive bladder cancer - beyond conventional risk stratification

The global incidence of bladder cancer is more than half a million diagnoses each year. Bladder cancer can be categorized into non-muscle-invasive bladder cancer (NMIBC), which accounts for ~75% of diagnoses, and muscle-invasive bladder cancer (MIBC). Up to 45% of patients with NMIBC develop disease progression to MIBC, which is associated with a poor outcome, highlighting a clinical need to identify these patients. Current risk stratification has a prognostic value, but relies solely on clinicopathological parameters that might not fully capture the complexity of disease progression. Molecular research has led to identification of multiple crucial players involved in NMIBC progression. Identified biomarkers of progression are related to cell cycle, MAPK pathways, apoptosis, tumour microenvironment, chromatin stability and DNA-damage response. However, none of these biomarkers has been prospectively validated. Reported gene signatures of progression do not improve NMIBC risk stratification. Molecular subtypes of NMIBC have improved our understanding of NMIBC progression, but these subtypes are currently unsuitable for clinical implementation owing to a lack of prospective validation, limited predictive value as a result of intratumour subtype heterogeneity, technical challenges, costs and turnaround time. Future steps include the development of consensus molecular NMIBC subtypes that might improve conventional clinicopathological risk stratification. Prospective implementation studies of biomarkers and the design of biomarker-guided clinical trials are required for the integration of molecular biomarkers into clinical practice.

Prognostic significance of EGFR, AREG and EREG amplification and gene expression in muscle invasive bladder cancer

Introduction

Muscle invasive bladder cancer (MIBC) remains a prevalent cancer with limited therapeutic options, obviating the need for innovative therapies. The epidermal growth factor receptor (EGFR) is a linchpin in tumor progression and presents a potential therapeutic target in MIBC. Additionally, the EGFR ligands AREG and EREG have shown associations with response to anti-EGFR therapy and improved progression-free survival in colorectal carcinoma.

Materials and methods

We investigated the prognostic significance of EGFR, AREG, and EREG in MIBC. Gene expression and copy number analyses were performed via qRT-PCR on tissue samples from 100 patients with MIBC who underwent radical cystectomy at the University Hospital Mannheim (MA; median age 72, interquartile range [IQR] 64-78 years, 25% female). Results were validated in 361 patients from the 2017 TCGA MIBC cohort (median age 69, IQR 60-77 years, 27% female), in the Chungbuk and MDACC cohort. Gene expressions were correlated with clinicopathologic parameters using the Mann-Whitney test, Kruskal-Wallis- test and Spearman correlation. For overall survival (OS), cancer-specific survival (CSS) and disease-free survival (DFS) gene expression was analyzed with Kaplan-Meier and Cox-proportional hazard models.

Results

Significant gene expression differences in EGFR, AREG, and EREG could be detected in all cohorts. In the TCGA cohort, EGFR expression was significantly elevated in patients with EGFR amplification and KRAS wildtype. High AREG expression independently predicted longer OS (HR = 0.35, CI 0.19 - 0.63, p = 0.0004) and CSS (HR = 0.42, CI 0.18 - 0.95, p = 0.0378) in the MA cohort. In the TCGA cohort, high EGFR, AREG, and EREG expression correlated with shorter OS (AREG: HR = 1.57, CI 1.12 - 2.20, p = 0.0090) and DFS (EGFR: HR = 1.91, CI 1.31 - 2.8, p = 0.0008). EGFR amplification was also associated with reduced DFS.

Discussion

High EGFR and EREG indicate worse survival in patients with MIBC. The prognostic role of AREG should further be investigated in large, prospective series. Divergent survival outcomes between the four cohorts should be interpreted cautiously, considering differences in analysis methods and demographics. Further in vitro investigations are necessary to elucidate the functional mechanisms underlying the associations observed in this study.

Clinical and pathological risk factors for tumour recurrence and upstaging in second TURBT for patients with NMIBC: a systematic review and meta-analysis

ZIEL: Offenlegung signifikanter Risikofaktoren durch Identifizierung gepoolter Effektschätzungsstatistiken in einer systemischen Überprüfung und Metaanalyse klinischer und pathologischer Risikofaktoren, die ein Tumorrezidiv und ein Upstaging auf eine zweite TURBT bei Patienten mit hochgradigem NMIBC vorhersagen.

MATERIAL-METHODE

Alle Datenquellen wurden umfassend bis Oktober 2022 untersucht. Die Daten wurden aus den relevanten Studien extrahiert und mit der Software RevMan analysiert. In einem inversen Varianzmodell mit zufälligen und festen Effekten werden Odds Ratio (OR)-Werte mit 95%-Konfidenzintervallen [95%-KI] angegeben.

ERGEBNISSE

Der Review umfasste insgesamt 18 Studien und 4548 Patienten. Gemäß den gepoolten Effektschätzern waren Carcinoma in situ (CIS), Tumorgrad, Multiplizität und Chirurgenfaktoren signifikante Risikofaktoren. Die gepoolten Effektschätzungen für das Tumorstadium und die Tumormorphologie waren sehr nahe an der Signifikanz. Für CIS, Grad, Multiplizität und Chirurgenfaktor, OR, IVR oder IVF [95%-KI] waren die p- und I2-Werte 1,8 [1,1, 3,0], 0,03, 75%; 2 [1,1, 3,4], 0,02, 53%; 1,3 [1,2, 1,6], <0,01, 40%; und 2 [1,4, 3], <0,01, 66%.

SCHLUSSFOLGERUNGEN

Als Ergebnis der ersten TURBT; Eine zweite TURBT sollte in den 2-6 Wochen der postoperativen Phase für Patienten mit hochgradigem, begleitendem CIS, multipler, solider Morphologie, DM(-) im pathologischen Präparat und NMIBC, das von Trainern/Juniorchirurgen operiert wird, geplant werden.

FLI1 and FRA1 transcription factors drive the transcriptional regulatory networks characterizing muscle invasive bladder cancer

Bladder cancer is mostly present in the form of urothelium carcinoma, causing over 150,000 deaths each year. Its histopathological classification as muscle invasive (MIBC) and non-muscle invasive (NMIBC) is the most prominent aspect, affecting the prognosis and progression of this disease. In this study, we defined the active regulatory landscape of MIBC and NMIBC cell lines using H3K27ac ChIP-seq and used an integrative approach to combine our findings with existing data. Our analysis revealed FRA1 and FLI1 as two critical transcription factors differentially regulating MIBC regulatory landscape. We show that FRA1 and FLI1 regulate the genes involved in epithelial cell migration and cell junction organization. Knock-down of FRA1 and FLI1 in MIBC revealed the downregulation of several EMT-related genes such as MAP4K4 and FLOT1. Further, ChIP-SICAP performed for FRA1 and FLI1 enabled us to infer chromatin binding partners of these transcription factors and link this information with their target genes. Finally, we show that knock-down of FRA1 and FLI1 result in significant reduction of invasion capacity of MIBC cells towards muscle microenvironment using IC-CHIP assays. Our results collectively highlight the role of these transcription factors in selection and design of targeted options for treatment of MIBC.

Non-muscle invasive bladder cancer biomarkers beyond morphology

Non-muscle invasive bladder cancer (NMIBC) still represents a challenge in decision-making and clinical management since prognostic and predictive biomarkers of response to treatment are still under investigation. In addition to the risk factors defined by EORTC guidelines, histological features have also been considered key variables able to impact on recurrence and progression in bladder cancer. Conversely, the role of genomic rearrangements or expression of specific proteins at tissue level need further assessment in NMIBC. As with muscle-invasive cancer, NMIBC is a heterogeneous disease, characterized by genomic instability, varying rates of mutation and a wide range of protein tissue expression. In this Review, we summarized the recent evidence on prognostic and predictive tissue biomarkers in NMIBC, beyond morphological parameters, outlining how they could affect tumor biology and consequently its behavior during clinical care. Our aim was to facilitate clinical evaluation of promising biomarkers that may be employed to better stratify patients. We described the most common molecular events and immunohistochemical protein expressions linked to recurrence and progression. Moreover, we discussed the link between available treatments and molecular drivers that could be predictive of clinical response. In conclusion, we foster further investigations with particular focus on immunohistochemical evaluation of tissue biomarkers, a promising and cost-effective tool for daily practice.

The Inequality of Females in Bladder Cancer

Urinary bladder cancer is worldwide one of the most diagnosed and costly types of cancer. One puzzle in the bladder cancer diagnosis is the disproportional relationship between genders. Males are more likely to be diagnosed with bladder cancer whereas females typically are diagnosed with more adverse disease and worse prognosis, which has led to speculation of the potential role of sex hormones and their receptors in this disease. Estrogen receptors are present in the human bladder, and their role in bladder cancer oncogenesis is increasingly becoming a focus for researchers around the world. This mini-review aims to give a brief overview of the status of female bladder cancer, and to which extend the sex hormones receptors play a role in this. A literature search was performed and included all female original studies on bladder cancer and hormone receptors. Estrogen-receptor alpha seems to be anti-oncogenic whereas estrogen-receptor beta is exhibiting its function pro-oncogenic. The receptor functions may be exercised through mRNA transcriptions and enzymes. Epidemiological studies indicate a potential increase in incidence of bladder cancer for females with earlier age at menopause, and clinical trials are investigating Tamoxifen as a potential treatment in bladder cancer. Increasing evidence supports the theory of bladder cancer development and progression as being partly hormone-dependent. This can lead to a change in conceptual background of bladder cancer etiology and development in the future. Further studies are required to more precise map the use of anti-hormonal drugs in the treatment of this cancer.

High expression of ERBB2 is an independent risk factor for reduced recurrence-free survival in patients with stage T1 non-muscle-invasive bladder cancer

INTRODUCTION

Molecular markers associated with breast cancer are assumed to be associated with outcome in non-muscle-invasive bladder cancer (NMIBC).

MATERIALS AND METHODS

We retrospectively investigated the association of the mRNA expression of estrogen receptor 1 (ESR1) and 2 (ESR2), progesterone receptor (PGR), MKI67, and HER2 (ERBB2) with recurrence-free (RFS), cancer-specific (CSS), and overall survival (OS) in 80 patients with stage T1 NMIBC.

RESULTS

High expression of ESR2 (P = 0.003), ERBB2 (P < 0.001), and MKI67 (P = 0.029) was associated with shorter RFS. Only high ERBB2 was an independent prognostic factor for reduced RFS (HR = 2.98; P = 0.009). When sub stratifying the cohort, high ESR2 was associated with reduced RFS (P < 0.001), CSS (P = 0.037) and OS (P = 0.006) in patients without instillation therapy. High ESR2 was associated with reduced CSS (P = 0.018) and OS (P = 0.029) in females and with shorter RFS in both sexes (males: P = 0.035; females: P = 0.010). Patients with high ERBB2 showed reduced CSS (P = 0.011) and OS (P = 0.042) in females and reduced CSS (P = 0.012) in those without instillation, while RFS was significantly reduced irrespective of sex or instillation.

CONCLUSION

High mRNA expression of ERBB2 is an independent predictor of reduced RFS in patients with stage T1 NMIBC. High ERBB2 and ESR2 are associated with reduced outcomes, especially in females and patients without instillation therapy.

A panel of eight mRNA signatures improves prognosis prediction of osteosarcoma patients

Genetic alterations are vital to the progression of osteosarcoma carcinoma. The present study investigated a panel of gene signatures that could evaluate prognosis in osteosarcoma based on data from the Therapeutically Applicable Research To Generate Effective Treatments initiative. Osteosarcoma messenger RNA (mRNA) profiles and clinical data were downloaded from the therapeutically applicable research to generate effective treatments database. Patients with osteosarcoma were divided into two groups based on findings at diagnosis: with and without metastasis. Differentially expressed mRNAs were compared and analyzed between groups. Univariate and multivariate Cox regression analyses identified a set of eight mRNAs with the ability to classify patients into high-risk and low-risk groups with significantly different overall survival times. Further analysis indicated that the eight-mRNA signature was an independent prognostic factor after adjusting for other clinical factors. Receiver operating characteristic curve analysis demonstrated a good performance of the eight-mRNA signature. Further, the biological processes and signaling pathways of the eight-mRNA signature were reviewed using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes resources. Finally, the results of the TCGA analysis were verified by other cohorts from Gene Expression Omnibus database. The identification of an eight-mRNA signature not only provides a prognostic biomarker of osteosarcoma but also offers the potential of novel therapeutic targets for its treatment.

Apparent Diffusion Coefficient Value can Predict Poor Bacillus Calmette-Guérin Responders in T1HG/NMIBC: Prospective Cohort Study

BACKGROUND

Prediction of recurrence and progression and the choice of type of management are largely based on stage and grade; however, these prognostic features are limited in the prediction of clinical outcomes. The objective was to investigate the relation between the apparent diffusion coefficient (ADC) value and recurrence and progression of T1G3 of urothelial carcinoma after transurethral resection of the bladder tumor (TURBT) and Bacillus Calmette-Guérin instillation.

MATERIALS AND METHODS

This prospective study included 65 patients with single bladder mass T1G3 less than 3 cm without carcinoma in situ or lymphovascular invasion. Mean ADC values of the tumors were compared between patients with and without recurrence and progression following TURBT. The relation of ADC value and other factors were determined by univariate and multivariate analyses. The following tests were used to test differences for significance: difference and association of qualitative variable by χ² test; differences between quantitative independent groups by t-test or Mann-Whitney U test; survival by Kaplan-Meier; Cox regression (or Cox proportional hazards model) was used to analyze the effect of several risk factors on time until event (recurrence and progression); correlation by Pearson or Spearman, and we calculated the most suitable cutoff and validity by receiver operating characteristic curve.

RESULTS

In relation to recurrence, smoking, nonpapillary shape and higher size, and lower ADC were significant predictors for recurrence. In relation to progression, female sex, nonpapillary shape, and lower ADC were significant predictors for progression. Multivariate analysis showed that ADC < 1.09 was the only significant independent predictors for recurrence. Also, it showed that ADC < 0.98 was the only significant independent predictors for progression.

CONCLUSION

Low ADC value group of T1G3 bladder cancer showed significant recurrence and progression than high ADC value group of T1G3 bladder cancer. ADC value in conjunction with other risk stratifications will have a promising role in stratifying patients with T1G3 who need to proceed to early radical cystectomy versus conservative treatment.

A comprehensive molecular characterization of the 8q22.2 region reveals the prognostic relevance of OSR2 mRNA in muscle invasive bladder cancer

Technological advances in molecular profiling have enabled the comprehensive identification of common regions of gene amplification on chromosomes (amplicons) in muscle invasive bladder cancer (MIBC). One such region is 8q22.2, which is largely unexplored in MIBC and could harbor genes with potential for outcome prediction or targeted therapy. To investigate the prognostic role of 8q22.2 and to compare different amplicon definitions, an in-silico analysis of 357 patients from The Cancer Genome Atlas, who underwent radical cystectomy for MIBC, was performed. Amplicons were generated using the GISTIC2.0 algorithm for copy number alterations (DNA_Amplicon) and z-score normalization for mRNA gene overexpression (RNA_Amplicon). Kaplan-Meier survival analysis, univariable, and multivariable Cox proportional hazard ratios were used to relate amplicons, genes, and clinical parameters to overall (OS) and disease-free survival (DFS). Analyses of the biological functions of 8q22.2 genes and genomic events in MIBC were performed to identify potential targets. Genes with prognostic significance from the in silico analysis were validated using RT-qPCR of MIBC tumor samples (n = 46). High 8q22.2 mRNA expression (RNA-AMP) was associated with lymph node metastases. Furthermore, 8q22.2 DNA and RNA amplified patients were more likely to show a luminal subtype (DNA_Amplicon_core: p = 0.029; RNA_Amplicon_core: p = 0.01). Overexpression of the 8q22.2 gene OSR2 predicted shortened DFS in univariable (HR [CI] 1.97 [1.2; 3.22]; p = 0.01) and multivariable in silico analysis (HR [CI] 1.91 [1.15; 3.16]; p = 0.01) and decreased OS (HR [CI] 6.25 [1.37; 28.38]; p = 0.0177) in RT-qPCR data analysis. Alterations in different levels of the 8q22.2 region are associated with manifestation of different clinical characteristics in MIBC. An in-depth comprehensive molecular characterization of genomic regions involved in cancer should include multiple genetic levels, such as DNA copy number alterations and mRNA gene expression, and could lead to a better molecular understanding. In this study, OSR2 is identified as a potential biomarker for survival prognosis.

Biomarkers predicting oncological outcomes of high-risk non-muscle-invasive bladder cancer

INTRODUCTION

The European Organization for Research and Treatment of Cancer (EORTC) and the Spanish Urological Club for Oncological Treatment (CUETO) scoring systems show limited accuracy for the prediction of disease recurrence and progression of non-muscle-invasive bladder cancer (NMIBC). This aspect is even more relevant in the category of HR NMIBC. Biomarkers might potentially help to further categorize the outcomes of these patients. Therefore, we sought to review the evidence available on tissue-based, urinary, and serum biomarkers for the prediction of recurrence, progression, and survival in HR NMIBC.

EVIDENCE ACQUISITION

A systematic literature review without time restrictions was performed using PubMed/EMBASE, Web of Science, SCOPUS, and the Cochrane Libraries. The search was filtered for articles in the English, Italian, German, French, and Spanish languages, involving patients with more than 18 years of age. Relevant papers on tissue-based, serum and urinary biomarkers related to the prediction of oncological outcomes for high-risk bladder cancer patients were included in the analyses.

EVIDENCE SYNTHESIS

Overall, 71 studies were eligible for inclusion in this review. The majority of the investigations performed so far focused on immunohistochemical analyses on tumoral tissue. Overall, p53 was the most studied biomarker, but results regarding its prognostic and predictive role were contradictory. Ki67 seems to be a promising biomarker in the prediction of recurrence. Recently, PD-L1 has been associated with the prediction of recurrence free survival and of treatment-refractory disease. Markers developed un urine samples are focused on commercially available kits, which currently do not unequivocally show strongly superior levels of accuracy to cytology. However, they have demonstrated to be potentially helpful in the prediction of recurrence. Blood-based biomarkers represent an emerging reality with promising future applications.

CONCLUSIONS

Despite a long history of attempts to discover accurate biomarkers predicting oncological outcomes for HR NMIBC, contradictory or uncertain findings render the adoption of this ancillary techniques in clinical practice still unlikely. Future attempts should be directed to the development of prospective trials and the definition of standardized cut-off levels to render findings worthy of comparison.

FOXA1 Gene Expression for Defining Molecular Subtypes of Muscle-Invasive Bladder Cancer after Radical Cystectomy

It remains unclear how to implement the recently revealed basal and luminal subtypes of muscle-invasive bladder cancer (MIBC) into daily clinical routine and whether molecular marker panels can be reduced. The mRNA expression of basal (KRT5) and luminal (FOXA1, GATA3, KRT20) markers was measured by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) and correlated to clinicopathological features, recurrence-free survival (RFS), disease-free survival (DFS), and overall survival (OS) in 80 patients with MIBC who underwent radical cystectomy. Additionally, the correlation of single markers with the basal and non-basal subtypes defined by a 36-gene panel was examined and then validated in the TCGA (The Cancer Genome Atlas) cohort. High expression of FOXA1 (p = 0.0048) and KRT20 (p = 0.0317) was associated with reduced RFS. In the multivariable analysis, only FOXA1 remained an independent prognostic marker for DFS (p = 0.0333) and RFS (p = 0.0310). FOXA1 expression (AUC = 0.79; p = 0.0007) was closest to the combined marker expression (AUC = 0.79; p = 0.0015) in resembling the non-basal subtype defined by the 36-gene panel. FOXA1 in combination with KRT5 may be used to distinguish the basal and non-basal subtypes of MIBC.

Mutation signatures to Pan-Cancer Atlas: Investigation of the genomic landscape of muscle-invasive bladder cancer

The Cancer Genome Atlas (TCGA) for bladder cancer was published in 2014 with updated annotation of over 400 patients with muscle-invasive bladder cancer (MIBC) in 2017. This tremendous work established the foundation of the genomic landscape of MIBC. The next steps to utilize information from The Cancer Genome Atlas is to (1) identify the causes of mutation, (2) determine the significant differences and sources of heterogeneity, and (3) apply these tools toward patient care. In this review, we discuss the full spectrum of the genomic landscape of MIBC toward the goal of therapeutic application.

Genomic and Therapeutic Landscape of Non-muscle-invasive Bladder Cancer

Non-muscle-invasive bladder cancer (NMIBC) is heterogeneous, but current diagnostic and treatment strategies rely primarily on clinical parameters, lacking individualization to tumor and host genetics and biology. The heterogeneity of NMIBCs is derived from mutations, mutation signatures, chromosomal loss, and disruption of molecular pathways, which ultimately affects tumor progression, recurrence, and responsiveness to intravesical and systemic chemotherapy. Although research is still underway, advances in sequencing technology, insight into differential bacillus Calmette-Guérin responses, and new investigational treatment targets will soon offer clinicians new, precision-based tools to risk stratify and determine treatment regimens for future patients with bladder cancer.

Metastatic non-muscle invasive bladder can-cer with cervical lymph node metastasis

Bladder cancer is a common cancer that may present as superficial, invasive, or metastatic disease. Non-muscle-invasive bladder cancer (NMIBC) represents the majority of bladder cancer diagnoses, but represents a spectrum of disease with a variable clinical course, notably for significant risk of recurrence and potential for progression. NMIBC metastasis to distant organs without local invasion or regional metastasis is a very rare occurrence, so there are limi-ted case reports about early metastasis in the literature.

Metastatic non-muscle invasive bladder cancer with cervical lymph node metastasis

Bladder cancer is a common cancer that may present as superficial, invasive, or metastatic disease. Non-muscle-invasive bladder cancer (NMIBC) represents the majority of bladder cancer diagnoses, but represents a spectrum of disease with a variable clinical course, notably for significant risk of recurrence and potential for progression. NMIBC metastasis to distant organs without local invasion or regional metastasis is a very rare occurrence, so there are limited case reports about early metastasis in the literature.

The Role and Importance of Timely Radical Cystectomy for High-Risk Non-muscle-Invasive Bladder Cancer

Non-muscle-invasive bladder cancer accounts for the majority of incident bladder cancers but is a heterogeneous disease with variation in clinical presentation, course, and outcomes. Risk stratification techniques have attempted to identify those at highest risk of cancer recurrence and progression to help personalize and individualize treatment options. Radical cystectomy during the optimal window of curability could improve cancer outcomes; however, identifying the disease and patient characteristics as well as the correct timing to intervene remains difficult. We review the natural history of non-muscle-invasive bladder cancer, discuss different risk-stratification techniques and how they can help identify those most likely to benefit from radical treatment, and examine the evidence supporting the benefit of timely cystectomy.

Analysis of the prognostic relevance of sex-steroid hormonal receptor mRNA expression in muscle-invasive urothelial carcinoma of the urinary bladder

Muscle-invasive urothelial carcinoma of the urinary bladder (UCB) often recurs following radical cystectomy (RC). An altered expression of sex-steroid hormone receptors has been associated with oncological outcomes of UCB and may represent therapeutic targets. Here the expression of different hormone receptors was measured on mRNA levels in patients treated by RC and associated with outcomes. Androgen receptor (AR), estrogen receptor 1 (ESR1), and progesterone receptor (PGR) mRNA expression was assessed by quantitative reverse transcription polymerase chain reaction (RT-qPCR) in RC samples of 87 patients with a median age of 66 (39-88) years. Univariate and multivariate analyses were performed to test associations with pathological and clinical characteristics as well as recurrence-free (RFS) and disease-specific survival (DSS). AR mRNA expression was lower in comparison with ESR1 and PGR expression (p < 0.0001). In univariate analysis, high expression levels of AR were associated with reduced RFS (HR 2.8, p = 0.015) and DSS (HR 2.8, p = 0.010). High AR mRNA expression and a positive lymph node status were independent predictors for reduced RFS (HR 2.5, p = 0.0049) and DSS (HR 3.4, p = 0.009). In patients with low AR mRNA expression, an increased ESR1 and PGR mRNA expression were associated with reduced RFS and DSS. High expression levels of AR are significantly associated with adverse outcome in patients with muscle-invasive UCB following RC. ESR1 and PGR expression status can further stratify patients with low AR expression into subgroups with significantly reduced RFS and DSS. Therapeutic targeting of AR may influence outcomes in patients with UCB.

mRNA-Expression of KRT5 and KRT20 Defines Distinct Prognostic Subgroups of Muscle-Invasive Urothelial Bladder Cancer Correlating with Histological Variants

Recently, muscle-invasive bladder cancer (MIBC) has been subclassified by gene expression profiling, with a substantial impact on therapy response and patient outcome. We tested whether these complex molecular subtypes of MIBC can be determined by mRNA detection of keratin 5 (KRT5) and keratin 20 (KRT20). Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) was applied to quantify gene expression of KRT5 and KRT20 using TaqMan®-based assays in 122 curatively treated MIBC patients (median age 68.0 years). Furthermore, in silico analysis of the MD Anderson Cancer Center (MDACC) cohort (GSE48277 + GSE47993) was performed. High expression of KRT5 and low expression of KRT20 were associated with significantly improved recurrence-free survival (RFS) and disease-specific survival disease specific survival (DSS: 5-year DSS for KRT5 high: 58%; 5-year DSS for KRT20 high: 29%). KRT5 and KRT20 were associated with rates of lymphovascular invasion and lymphonodal metastasis. The combination of KRT5 and KRT20 allowed identification of patients with a very poor prognosis (KRT20⁺/KRT5-, 5-year DSS 0%, p < 0.0001). In silico analysis of the independent MDACC cohorts revealed congruent results (5-year DSS for KRT20 low vs. high: 84% vs. 40%, p = 0.042). High KRT20-expressing tumors as well as KRT20⁺/KRT- tumors were significantly enriched with aggressive urothelial carcinoma variants (micropapillary, plasmacytoid, nested).

Prognostic Value of Molecular Breast Cancer Subtypes based on Her2, ESR1, PGR and Ki67 mRNA-Expression in Muscle Invasive Bladder Cancer

INTRODUCTION: Gene expression analyses have identified similarities between bladder and breast cancer, where clinical risk stratification is based on Her2, ESR1, PGR and Ki67 expression. The aim of the study was to assess the respective marker gene expression in patients treated with radical cystectomy for muscle-invasive bladder cancer (MIBC) and to evaluate the applicability of breast cancer subtypes for MIBC risk stratification. MATERIALS & METHODS: 102 patients treated with radical cystectomy for MIBC were assessed. Using routine FFPE tissue and an IVD validated kit, mRNA expression was measured by single step RT-qPCR. Partition test were employed to define cut-off values for high or low marker gene expression. Association of expression with outcome was assessed using Kaplan-Meier analysis and multivariate cox regression analysis. Finally, we performed validation of our results in the MD-Anderson cohort (n = 57). RESULTS: Cancer specific survival (CSS) was impaired in patients with high gene expression of Her2 (P = 0.0009) and ESR1 (P = 0.04). In the multivariate regression model Her2 expression remained significant for the prediction of CSS (HR = 2.11, CI 1.11-4.21, P = 0.024). Furthermore, molecular stratification by breast cancer subgroups was significant (P = 0.023) for CSS prediction. Especially the differentiation between Her2-positive and Luminal A (HR = 4.41, CI 1.53-18.71, P = 0.004) and Luminal B (HR = 1.96, CI 0.99-4.08, P = 0.053) respectively was an independent prognostic parameter for CSS. External validation resulted in comparable risk stratification with differences in fractional subgroups distribution. CONCLUSION: Gene expression of Her2, ESR1, PGR, Ki67 and corresponding breast cancer subtypes allow a risk-stratification in MIBC, whereby Her2 overexpressing tumors reveal a particularly poor prognosis.

A multicenter round robin test of PD-L1 expression assessment in urothelial bladder cancer by immunohistochemistry and RT-qPCR with emphasis on prognosis prediction after radical cystectomy

Background

Immunohistochemical PD-L1 assessment is currently used to identify responders towards checkpoint inhibitors although it is limited by inter-observer effects. Here, we conducted a multi-center round robin test to prove the possibility of assessing the PD-L1 status by gene expression to avoid inter-observer effects.

Patients and methods

Gene expression of PD-L1 was analyzed in a total of 294 samples (14 cases non-muscle invasive and muscle-invasive bladder cancer; MIBC) in seven centers by a RT-qPCR kit and compared with immunohistochemical scoring of three pathologists (DAKO, 22c3). Both assays were compared towards prognosis prediction in a cohort of 88 patients with MIBC.

Results

PD-L1 gene expression revealed very high inter center correlation (centrally extracted RNA: r = 0.68–0.98, p ≤ 0.0076; locally extracted RNA: r = 0.81–0.98, p ≤ 0.0014). IHC Inter-observer concordance was moderate to substantial for immune cells (IC), fair for combined IC/ tumor cell (TC) (IC: κ = 0.50–0.61; IC + TC: κ = 0.50), and fair for TC scoring (κ = 0.26–0.35). Gene expression assessment resulted in more positive cases (9/14 cases positive vs. 6/14 cases [IHC]) which could be validated in the independent cohort. Positive mRNA status was associated with significantly better overall and disease-specific survival (5-year OS: 50% vs. 26%, p = 0.0042, HR = 0.48; 5 year DSS: 65% vs. 40%, p = 0.012, HR = 0.49). The 1% IHC IC cut-off also revealed significant better OS (5 year OS: 58% vs. 31%, p = 0.036, HR = 0.62).

Conclusion

Gene expression showed very high inter-center agreement. Gene expression assessment also resulted in more positive cases and revealed better prognosis prediction. PD-L1 mRNA expression seems to be a reproducible and robust tool for PD-L1 assessment.