RESUMO
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.
RESUMO
BACKGROUND: The cell surface interleukin 22 (IL-22) receptor complex is mainly expressed in epithelial and tissue cells like pancreatitis cells. Recent studies described that IL-22R was overexpressed in malignant diseases and was associated with a poor overall survival (OS). The role of IL-22RA1 gene expression in muscle invasive bladder cancer (MIBC) has not been investigated, yet. OBJECTIVES: The aim of this study was to analyze the role of IL-22RA1 gene expression in patients with MIBC. METHODS: In a cohort of 114 patients with MIBC who underwent radical cystectomy, IL-22RA1 gene expression was analyzed with qRT-PCR and correlated with clinical parameters. Furthermore, Kaplan-Meier and Cox regression analysis were performed. For validation, an in silico dataset (TCGA 2017, n=407) was reanalyzed. RESULTS: IL-22RA1 gene expression was independent of clinicopathological parameters like age (P=0.2681), T stage (P=0.2130), nodal status (P=0.3238) and lymph vascular invasion (LVI, P=0.5860) in patients with MIBC. A high expression of IL-22RA1 was associated with a shorter OS (P=0.0040) and disease-specific survival (P=0.0385). Furthermore, a shorter disease-free survival (DFS) was also associated with a high expression of IL-22RA1 (P=0.0102). In the multivariable analysis, IL-22RA1 expression was an independent prognostic predictors regarding OS (P=0.0096, HR=0.48). In the TCGA cohort, IL-22RA1 expression was independent regarding to OS and DFS. CONCLUSION: A high IL-22RA1 gene expression was associated with worse outcome. Furthermore, IL-22RA1 represented an independent predictor regarding OS in our cohort and therefore might be used for risk stratification in patients with MIBC.