miRNA Profiling of Hungarian Regressive Wilms’ Tumor Formalin-Fixed Paraffin-Embedded (FFPE) Samples by Quantitative Real-Time Polymerase Chain Reaction (RT-PCR)

Abstract

Background Wilms’ tumor is a common renal malignancy of early childhood with a generally favorable prognosis depending upon histological subtype. It is becoming increasingly clear that differences in miRNA (microRNA) expression signature represent important clues helping us predict a tumor’s response to chemotherapy. In our study, we aimed to reveal miRNAs deregulated in regressive Wilms’ tumors from FFPE (formalin-fixed, paraffin-embedded) samples, also showing whether such samples are reliable miRNA sources in Wilms’ tumor. Material/Methods Samples from 8 Hungarian patients (3 males, 5 females, aged 1 to 7 years) were analyzed by qRT-PCR (quantitative real-time PCR). A PCR array was used in a pilot experiment, and selected miRNAs (miR-128-3p, miR-184, miR-194-5p, miR-203a) were studied in the rest of the samples using individual primers. Results miR-194-5p was underexpressed in all tumor samples. miR-184 and miR-203a were underexpressed in 7 cases, the exception being a case with a high ratio of necrotic blastemal tissue. Results obtained with miR-128-3p are difficult to interpret due to varying directions of expression changes. Conclusions We conclude that a downregulation of miR-184, miR-194-5p, and miR-203a expression is observed in both regressive and blastemal tumors, but larger-scale studies are needed to confirm whether the degree of their underexpression correlates with the number of blastemal elements in a sample. In most of our FFPE samples aged up to 9 years, RNA extraction provided miRNA with quantity and quality sufficient for qRT-PCR-based analysis, emphasizing the relevance of pathological archives as miRNA sources in future studies.

Integrative Transcriptomic Profiling Reveals Novel Biomarkers in Wilms Tumor

“…In this context, miR-200b-3p has been identi ed to be associated with metastatic WT [35], and our results indicate that miR-200b-3p is a potential universal WT miRNA. Recent studies have reported interesting results regarding the downregulation of miR-184 and miR-194-5p in both regressive and blastemal tumors [24,25]. Our ndings support these results for differentially expressed miRNAs, but put the identi ed miRNAs in the context of universal and ubiquitous markers of WT.…”

miR‐203a—A multifaceted regulator modulating cancer hallmarks and therapy response

“…88 Bugly o et al observed that lower expression of miR-203a in Wilms' tumor (WT) tissues has prognostic value for cancer development. 90 Further, the downregulation of miR-203a in primary melanoma 94 serves as a potential biomarker for metastatic cutaneous melanoma (MCM). 86 A study on intracranial ependymoma shows that increased expression of miR-203a was correlated with grade III tumors and could assist as a prognostic and diagnostic marker for ependymoma.…”

“…Infection of the Hepatitis‐C virus suppresses the expression of miR‐203a and increases EMT in HCC cell lines, so the loss of miR‐203a marks a poor prognosis 88 . Buglyó et al observed that lower expression of miR‐203a in Wilms' tumor (WT) tissues has prognostic value for cancer development 90 . Further, the downregulation of miR‐203a in primary melanoma 94 serves as a potential biomarker for metastatic cutaneous melanoma (MCM) 86 .…”

Örökletes vesetumor-szindrómák.

“…1/8000 gyermek, így Magyarorszá gon durván 6-8 Wilmstumort lehet diagnosztizálni évente [62]. A daganat nőkben kissé gyakoribb, és az esetek 10-15%a társul daganatszindrómákhoz, amelye ket pontmutációk, deletiók, epigenetikai módosulások hoznak létre, viszont Wilmstumorokban megfigyelték már a mikroRNSek eltéréseit is [62][63][64]. Az utóbbiak biomarkerként használva akár a terápiás választ is elő jelezhetik [65].…”