Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy, with a steadily increasing incidence in the last few decades worldwide. The predisposition to developing this carcinoma by the heterozygous state of rs2910164 within the precursor of the miR-146a has been reported, but recently not confirmed. Interestingly, on the same chromosome, almost 50 kb separate the pre-miR-146a from the pituitary tumor-transforming gene 1 (PTTG1), a proto-oncogene involved in several tumors, including thyroid cancers. In this study, we analyzed, using a case–control design, the genetic association between PTC and the genomic region encompassing pre-miR-146a rs2910164 and PTTG1 rs1862391 and rs2910202. We enrolled 307 affected patients and 206 healthy controls. The possible presence of thyroid nodules in controls was excluded by ultrasonography. All the cases were submitted to single-nucleotide polymorphism (SNP) genotyping of pre-miR-146a and PTTG1, and risk association analyses were carried out. The genotypic and allelic frequencies of pre-miR-146a rs2910164 were not statistically different in the patients and controls, and this SNP was not in linkage disequilibrium with the investigated PTTG1 SNPs. Consistently, meta-analyses, the first including all the affected cases published to date, did not confirm the previously reported association of the heterozygous CG genotype with PTC. The PTTG1 SNPs exhibited the same allelic frequency in the patients and controls and were not associated with the disease. In conclusion, in a well-selected Italian population, neither pre-miR-146a rs2910164 nor PTTG1 rs1862391 and rs2910202 were found to be associated with the risk of developing PTC.
Marco Marino, Valentina Cirello, Valentina Gnarini, Carla Colombo, Elisa Pignatti, Livio Casarini, Chiara Diazzi, Vincenzo Rochira, Katia Cioni, Bruno Madeo, Cesare Carani, Manuela Simoni and Laura Fugazzola
Roberto Cosimo Melcangi, Livio Casarini, Marco Marino, Daniele Santi, Samantha Sperduti, Silvia Giatti, Silvia Diviccaro, Maria Grimoldi, Donatella Caruso, Guido Cavaletti and Manuela Simoni
Post-finasteride syndrome (PFS) occurs in patients with androgenic alopecia after suspension of the finasteride treatment, leading to a large variety of persistent side effects. Despite the severity of the clinical picture, the mechanism underlying the PFS symptoms onset and persistence is still unclear.
To study whether epigenetic modifications occur in PFS patients.
Retrospective analysis of a multicentric, prospective, longitudinal, case–control clinical trial, enrolling 16 PFS patients, compared to 20 age-matched healthy men. Main outcomes were methylation pattern of SRD5A1 and SRD5A2 promoters and concentration of 11 neuroactive steroids, measured by liquid chromatography-tandem mass spectrometry, in blood and cerebrospinal fluid (CSF) samples.
SRD5A1 and SRD5A2 methylation analysis was performed in all blood samples (n = 16 PFS patients and n = 20 controls), in 16 CSF samples from PFS patients and in 13 CSF samples from controls. The SRD5A2 promoter was more frequently methylated in CSF of PFS patients compared to controls (56.3 vs 7.7%). No promoter methylation was detected in blood samples in both groups. No methylation occurred in the SRD5A1 promoter of both groups. Unmethylated controls compared to unmethylated SRD5A2 patients showed higher pregnenolone, dihydrotestosterone and dihydroprogesterone, together with lower testosterone CSF levels. Andrological and neurological assessments did not differ between methylated and unmethylated subjects.
For the first time, we demonstrate a tissue-specific methylation pattern of SRD5A2 promoter in PFS patients. Although we cannot conclude whether this pattern is prenatally established or induced by finasteride treatment, it could represent an important mechanism of neuroactive steroid levels and behavioural disturbances previously described in PFS.