Basic Research - Cancer(구연) Oral Session 3 / Basic Research - Cancer (Ⅱ) (O-028) Rm.201 10월 30일(수) 14:00-15:00 Molecular Subtypes of Non-muscle Invasive Bladder Cancer 충북대학교 의과대학 비뇨의학교실 정필두, 변영준, 박현미, 이희윤, 서성필, 강호원, 김원태, 김용준, 윤석중, 이상철, 김원재 More recently molecular inter-tumor heterogeneity has been investigated, leading to the identification of distinct molecular classes beyond histopathological classification and with differences in clinical outcomes. Most studies have focused primarily on muscle-invasive bladder cancers (MIBC) or combined analysis of non-muscle invasive bladder cancer (NMIBC) and MIBC. Three molecular subclasses of NMIBC has been previously delineated from a European multicenter prospective study of NMIBC (FP7: UROMOL) using 8,074 genes. The clusters were different with respect to progression-free survival and clinical and histopathological features. Here, we performed unsupervised consensus clustering of mRNA microarray data to subclassify NMIBC and seek the relationships with clinical outcomes. Gene expression analysis on 99 NMIBC tissue samples from Chungbuk National University Hospital showed that NMIBC can be subgrouped into three different clusters with different clinical outcomes such as pathological grade and disease progression. Tumors of high grade and progression to MIBC were more frequently observed in cluster 3 than in clusters 1 and 2. We then applied the differentially expressed genes, which developed this classifier, to RNA-sequencing data from UROMOL, and excavated two different clusters with different clinical outcomes. NMIBC patients with high stage and grade, concomitant CIS, with high clinical risk (high EORTC [European Organization for Research and Treatment of Cancer] risk scores), and those with progression to MIBC were predominantly found in cluster 1 than in cluster 2. To the contrary, when applied those genes from UROMOL to our mRNA microarray data from 99 NMIBC patients, the clusters showed no significant concordance with clinical or histopathological features. Conclusively, these observations have important implications for prognostication of NMIBC patients. keywords : Non-muscle Invasive Bladder Cancer, classifier, mRNA