Project description:We investigated the expression profiles of microRNAs (miRNA) in 26 renal cell carcinoma (RCC) FFPE tissues (3 chRCC, 5 papRCC and 18 ccRCC), 4 urothelial cell carcinomas of the upper urinary tract (UT-UCs) and 20 normal kidneys by using the miRCURY LNA™ microRNA Array, 6th gen (Exiqon, Woburn MA), containing capture probes that target all miRNAs for all species registered in the miRBASE version 16.0. Real-time PCR (qRT-PCR) using appropriate endogenous controls was performed in order to validate the microarray results of the 27 most differentially expressed (DE) miRNAs. We identified 434 miRNAs that were significantly deregulated in all tumours compared to the normal kidney tissues. Overall, 126 miRNAs (29%) showed increased expression and 303 miRNAs (69.8%) had decreased expression in RCCs and UT-UCs vs. the normal kidneys. Specifically, 374, 420, 421 and 409 miRNAs were 90% consistently down-regulated in ccRCC, papRCC, chRCC and UT-UC, respectively. Unsupervised two-way hierarchical clustering (HCL) with Euclidian distance accurately discriminated between RCC and UT-UC. Apart from one chRCC sample that was clustered with ccRCCs, HCL also managed to successfully classify the 3 RCC subtypes among them. Furthermore, it showed that ccRCC is more closely related to papRCC and that both are distinct from chRCC or UT-UC. Ninety-four miRNAs were co-upregulated among ccRCC, papRCC and chRCC; and 11, 44 and 24 miRNAs were specifically up-regulated in each one of the three RCC subtypes (ccRCC, chRCC and papRCC), respectively. On the other hand, 222 miRNAs were co-down-regulated in the three RCC subtypes, whereas 16, 18 and 5 miRNAs were specifically down-regulated in ccRCC, chRCC and papRCC, respectively. When the DE miRNAs in each RCC subtype were combined with those in UT-UC, we identified 89 and 206 miRNAs, respectively, that were up- and down-regulated in all tumor types. miRNA profiling can distinguish between RCC and UT-UC as well as among distinct RCC subtypes. Our data validicate that miRNA expression tends to be down-regulated in RCC versus the normal kidney tissue.

Project description:This study presents a comprehensive multi-omic analysis of upper urinary tract urothelial tumours (UTUC) and urines of patients with past exposure to carcinogenic aristolochic acid (AA). We determined complex miRNA:mRNA tumor networks and their key protein components. Tumor exome and transcriptome sequencing revealed a burden of AA-specific mutations in UTUC and identified deleteriously mutated genes and their mRNA transcripts. A subset of identified urinary miRNAs presents potential biomarkers of UTUC development or presence. Recurrent upper urinary tract carcinomas (UTUC) arise in the context of nephropathy linked to exposure to the herbal carcinogen aristolochic acid (AA). We aimed to delineate the detailed biological programs underlying UTUC tumorigenesis in patients from endemic aristolochic acid nephropathy (AAN) regions in Southern Europe, by using an integrative multi-omics analysis of UTUCs, corresponding unaffected tissues and of patient urines. Quantitative miRNA and mRNA expression profiling, immunohistochemical analysis by tissue microarrays, and exome and transcriptome sequencing were performed in UTUC and non-tumor tissues. Urinary miRNAsof cases undergoing surgery were profiled before and after UTUC resection. RNA and protein levels were analyzed using appropriate statistical tests and trend assessment. Dedicated bioinformatic tools were used for analysis of pathways, mutational signatures and result visualization. The results delineate UTUC-specific miRNA:mRNA networks comprising 89 miRNAs associated with 1862 target mRNAs and involving deregulation of cell cycle, DNA damage response, DNA repair, bladder cancer, oncogenes, tumor suppressors, chromatin structure regulators and developmental signaling pathways. Key UTUC-specific transcriptome components were confirmed at the protein level. Exome and transcriptome sequencing of UTUC revealed AA-specific COSMIC mutational signature 22, with 68-76% AA-specific, deleterious mutations propagated at the mRNA level. We next identified a signature of UTUC-specific miRNAs consistently more abundant in the patients’ urine prior to tumor resection. The gene regulation programs of AAN-associated UTUC tumors are highly complex and involve regulatory miRNAs prospectively applicable to non-invasive urine-based screening of AAN patients for cancer recurrence.

Dataset Information

New miRNA profiles accurately distinguish renal cell carcinomas and upper tract urothelial carcinomas from the normal kidney.

Background

Methods and findings

Conclusions

Publications

New miRNA profiles accurately distinguish renal cell carcinomas and upper tract urothelial carcinomas from the normal kidney.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure