MicroRNA Expression Profiling in Adrenal Myelolipoma

Area of Science:

• Endocrinology
• Molecular Biology
• Oncology

Background:

• Adrenal myelolipoma (AML) is a common benign adrenal neoplasm that can present diagnostic challenges due to its variable composition and size.
• MicroRNAs (miRNAs) have emerged as potential diagnostic markers for various tumors, but their role in AML has not been previously investigated.

Purpose of the Study:

• To investigate the differential expression of miRNAs in adrenal myelolipoma (AML) compared to adrenocortical adenoma (ACA) and adrenocortical carcinoma (ACC).
• To identify potential miRNA biomarkers for the diagnosis of AML and other adrenocortical tumors.

Main Methods:

• Next-generation sequencing (NGS) was employed to analyze miRNA expression in formalin-fixed, paraffin-embedded (FFPE) tissue samples of AML, ACA, and ACC.
• Validation of differentially expressed miRNAs was performed using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR).
• Circulating miRNAs in plasma were analyzed to assess their potential as non-invasive biomarkers.

Main Results:

• NGS identified 256 significantly differentially expressed miRNAs, with 8 selected for validation.
• Overexpression of hsa-miR-451a, hsa-miR-486-5p, hsa-miR-363-3p, and hsa-miR-150-5p was confirmed in AML compared to ACA and ACC.
• Circulating hsa-miR-451a and hsa-miR-363-3p were significantly overexpressed in AML patients.

Conclusions:

• This study identified significantly differentially expressed miRNAs in AML and other adrenocortical tumors.
• Circulating hsa-miR-451a shows promise as a minimally invasive biomarker for AML.
• The expression patterns of hsa-miR-483-3p and hsa-miR-483-5p may limit their utility as diagnostic markers for ACC.