Micro RNA expression and prognosis in low-grade non-invasive urothelial carcinoma

Abstract

ARTICLE INfO ______________________________________________________________ ______________________Purpose: To analyze a possible correlation between a miRNA expression profile and important prognostic factors for pTa urothelial carcinomas (UC), including tumor size, multiplicity and episodes of recurrence. Materials and Methods: Thirty low-grade non-invasive pTa bladder UC from patients submitted to transurethral resection were studied, in a mean follow-up of 17.7 months. As controls, we used normal bladder tissue from five patients submitted to retropubic prostatectomy to treat benign prostatic hyperplasia. Extraction, cDNA and amplification were performed for 14 miRNAs (miR-100, -10a, -21, -205, -let7c, -143, -145, -221, -223, -15a, -16, -199a and -452) using specific kits, and RNU-43 and -48 were used as endogenous controls. Statistical tests were used to compare tumor size, multiplicity and episodes of recurrence with miRNAs expression profiles.Results: There was a marginal correlation between multiplicity and miR-let7c over--expression. For all others miRNA no correlation between their expression and prognostic factors was found. Conclusion:We did not find differences for miRNAs expression profiles associated with prognostic factors in tumor group studied. The majority of miRNAs are down-regulated, except miR-10a, over-expressed in most of cases, seeming to have increased levels in tumor with more unfavorable prognostic factors. More studies are needed in order to find a miRNA profile able to provide prognosis in pTa UC to be used in clinical practice.

Repression of the miR-93-enhanced sensitivity of bladder carcinoma to chemotherapy involves the regulation of LASS2

“…Many studies of the miRNA profile in bladder cancer have been conducted, including in muscle-invasive BC, 20 , 21 low-grade non-invasive BC, 22 and non-invasive BC, 23 – 26 but few studies have investigated the chemo-resistance of BC. Kozinn et al conducted a microarray analysis comparing miRNA expression between gemcitabine-resistant and parental cells and identified the differential expression of 66 miRNAs.…”