Expression levels of C19MC and C14MC microRNAs in complete hydatidiform moles and ovarian mature cystic teratomas

Aim: To investigate whether comparative analysis of microRNA (miR) expression patterns in complete hydatidiform moles (androgenic origin) and ovarian mature cystic teratomas (parthenogenetic origin) could form the basis of a systematic screening system for parental allele-specific miRs, we measured expression in these tissues of the chromosome 19 miR cluster (C19MC; miR-517a, miR517c, and miR-518b), which has a paternal allele-specific expression pattern, and of C14MC (miR-323-3p), which also has a maternal allele-specific expression pattern. Materials and Methods: Sixteen cases of complete hydatidiform mole and 11 cases of ovarian teratoma were studied. Expression of each miR was measured by real-time quantitative reverse transcription-polymerase chain reaction, and the expression levels were compared in copies/mL. Statistical significance was defined as p < 0.05 by the Mann–Whitney non-parametric U test. Results: The median and (range) expression levels of miR-517a, -517c, and -518b in the hydatidiform moles were 747,082.6 (5,075.7–4,701,041.6), 480,759.6 (3,436.5–2,053,419.8), and 192,930.1 (37,478.7–4,381,175.2) copies/mL, respectively. Conversely, their expression levels in ovarian teratomas were below the limit of detection. The expression level of miR-323-3p was significantly higher in the ovarian teratomas at 9,700.7 (1,663.8–144,248.0) copies/mL than in the hydatidiform moles at 1,665.1 (193.4–5,029.5) copies/mL (p = 0.02). Conclusions: C19MC miRs were detected only in androgenic tissues. The C14MC miR-323-3p was detected in both types but it was significantly higher in parthenogenetic than in androgenic tissues. Thus, comparative analysis of miR expression patterns between these tissue types will help in developing a screening system for parental-specific miRs.

Androgenic; C19MC; C14MC; Hydatidiform mole; Ovarian teratoma; Parthenogenetic; Parental allele-specific expression.

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