Features of the fetal gonad in androgen synthesis in the postpubertal testis are preserved in complete androgen insensitivity syndrome due to a novel genetic splice site donor variant in androgen receptor gene intron 1

Androgen Insensitivity Syndrome with Bilateral Gonadal Sertoli Cell Lesions, Sertoli-Leydig Cell Tumor, and Paratesticular Leiomyoma: A Case Report and First Systematic Literature Review

Androgen insensitivity syndrome (AIS) is a rare Mendelian disorder caused by mutations of the androgen receptor (AR) gene on the long arm of the X chromosome. As a result of the mutation, the receptor becomes resistant to androgens, and hence, karyotypically male patients (46,XY) carry a female phenotype. Their cryptorchid gonads are prone to the development of several types of tumors (germ cell, sex cord stromal, and others). Here, we report a 15-year-old female-looking patient with primary amenorrhea who underwent laparoscopic gonadectomy. Histologically, the patient's gonads showed Sertoli cell hamartomas (SCHs) and adenomas (SCAs) with areas of Sertoli-Leydig cell tumors (SLCTs) and a left-sided paratesticular leiomyoma. Rudimentary Fallopian tubes were also present. The patient's karyotype was 46,XY without any evidence of aberrations. Molecular genetic analysis of the left gonad revealed two likely germline mutations-a pathogenic frameshift deletion in the AR gene (c.77delT) and a likely pathogenic missense variant in the RAC1 gene (p.A94V). Strikingly, no somatic mutations, fusions, or copy number variations were found. We also performed the first systematic literature review (PRISMA guidelines; screened databases: PubMed, Scopus, Web of Science; ended on 7 December 2023) of the reported cases of patients with AIS showing benign or malignant Sertoli cell lesions/tumors in their gonads (n = 225; age: 4-84, mean 32 years), including Sertoli cell hyperplasia (1%), Sertoli cell nodules (6%), SCHs (31%), SCAs (36%), Sertoli cell tumors (SCTs) (16%), and SLCTs (4%). The few cases (n = 14, 6%; six SCAs, four SCTs, two SLCTs, and two SCHs) with available follow-up (2-49, mean 17 months) showed no evidence of disease (13/14, 93%) or died of other causes (1/14, 7%) despite the histological diagnosis. Smooth muscle lesions/proliferations were identified in 19 (8%) cases (including clearly reported rudimentary uterine remnants, 3 cases; leiomyomas, 4 cases). Rudimentary Fallopian tube(s) were described in nine (4%) cases. Conclusion: AIS may be associated with sex cord/stromal tumors and, rarely, mesenchymal tumors such as leiomyomas. True malignant sex cord tumors can arise in these patients. Larger series with longer follow-ups are needed to estimate the exact prognostic relevance of tumor histology in AIS.

Persistence of foetal testicular features in patients with defective androgen signalling

OBJECTIVE

Congenital defects of androgen synthesis or action in 46,XY individuals can result in impaired virilisation, despite the apparent testicular development. In a recent case, report of a young adult with complete androgen insensitivity syndrome (CAIS), tumourous gonadal tissue was shown to express HSD17B3 in Sertoli cells (SCs) and not in Leydig cells (LCs). This expression pattern differs from the typical adult human testis and resembles a foetal mouse testis, suggesting an underlying testicular development and function defect. Here, we investigate the effect of altered androgen signalling in gonads from five 46,XY individuals with defects in androgen synthesis or action.

METHODS

Gonadal tissue sections from four patients with CAIS, one with CYP17A1 deficiency, and one control were immunostained for LC developmental and steroidogenic markers. The expression of some of these markers during development was investigated by reanalysing previously published single-cell RNA sequencing (scRNA-seq) data from normal human testicular tissues.

RESULTS

All gonadal tissues from the patients show an exclusive expression of HSD17B3 in SCs and an expression of the foetal/immature LC marker DLK1 in a subset of LCs, suggesting an androgen-dependent differentiation defect of adult SCs and LCs. Furthermore, reanalysis of scRNA-seq data reveals an expression of HSD17B3 in foetal and neonatal SCs that is downregulated in adult SCs.

CONCLUSIONS

Androgen signalling may affect the differentiation of adults, but possibly not foetal SCs or LCs, and may induce a shift of testosterone production from the tubular compartment in the foetal phase to the interstitial compartment in the adult phase.

18-Year-old patient with Klinefelter syndrome (47, XXY) and complete androgen insensitivity syndrome (CAIS) - case report

AIMS

The aims of the presented case report are to emphasize the importance of a proper diagnostics and treatment in the case of the coexistence of Klinefelter syndrome (KS, 47 XXY) and complete androgen insensitivity syndrome (CAIS). Since there is no causal treatment it is necessary to provide the patient with a good quality of life, including psychological and sexological support.

MATERIALS AND METHODS

The presented case report is the retrospective analysis of the patient's medical history over the 3 years.

RESULTS

At the age of 15, the patient was directed to genetic testing due to primary amenorrhea. The results of the patient showed an incorrect male karyotype with the SRY gene present (47, XXY). A molecular diagnostics revealed a very rare variant of the androgen receptor (AR) mutation responsible for tissue insensitivity to androgens. The detected mutation has not been described in the available databases so far. Following a diagnosis of the presence of Klinefelter syndrome (KS, 47 XXY) together with complete androgen insensitivity syndrome (CAIS), the patient underwent a bilateral gonadectomy.

CONCLUSIONS

In women with KS and CAIS physiological reproduction and maintenance of normal sex, hormone levels are not possible. A gonadectomy is performed due to the risk of malignant testicular tumors.

Identification of Potential Genes in Pathogenesis and Diagnostic Value Analysis of Partial Androgen Insensitivity Syndrome Using Bioinformatics Analysis

BACKGROUND

Androgen insensitivity syndrome (AIS) is a rare X-linked genetic disease and one of the causes of 46,XY disorder of sexual development. The unstraightforward diagnosis of AIS and the gender assignment dilemma still make a plague for this disorder due to the overlapping clinical phenotypes.

METHODS

Peripheral blood mononuclear cells (PBMCs) of partial AIS (PAIS) patients and healthy controls were separated, and RNA-seq was performed to investigate transcriptome variance. Then, tissue-specific gene expression, functional enrichment, and protein-protein interaction (PPI) network analyses were performed; and the key modules were identified. Finally, the RNA expression of differentially expressed genes (DEGs) of interest was validated by quantitative real-time PCR (qRT-PCR).

RESULTS

In our dataset, a total of 725 DEGs were captured, with functionally enriched reproduction and immune-related pathways and Gene Ontology (GO) functions. The most highly specific systems centered on hematologic/immune and reproductive/endocrine systems. We finally filtered out CCR1, PPBP, PF4, CLU, KMT2D, GP6, and SPARC by the key gene clusters of the PPI network and manual screening of tissue-specific gene expression. These genes provide novel insight into the pathogenesis of AIS in the immune system or metabolism and bring forward possible molecular markers for clinical screening. The qRT-PCR results showed a consistent trend in the expression levels of related genes between PAIS patients and healthy controls.

CONCLUSION

The present study sheds light on the molecular mechanisms underlying the pathogenesis and progression of AIS, providing potential targets for diagnosis and future investigation.