A comparison of prostatic development in xenografts of human fetal prostate and human female fetal proximal urethra grown in dihydrotestosterone-treated hosts

Ectopic Prostatic Tissue in Female Urethral Diverticulum

BACKGROUND

Ectopic prostatic tissue in female patients is rare. It is theorized that the presence of prostatic tissue in female patients is likely a Wolffian remnant or transformation of hormonally mediated tissue of the uterus, cervix, Skene's gland, and, rarely, periurethral tissue. Due to the increase in the use of testosterone and gender-affirming therapies, it is important to understand the role of testosterone in mediating the presence of ectopic prostatic tissue.

CASE

We present a case of ectopic prostatic tissue in a urethral diverticulum in a female patient with exposure to testosterone hormone therapy and review the literature on this finding.

CONCLUSION

Although rare, ectopic prostatic tissue should be considered in the differential diagnosis of anterior vaginal cysts, especially in the setting of testosterone supplementation.

Androgenic induction of penile features in postnatal female mouse external genitalia from birth to adulthood: Is the female sexual phenotype ever irreversibly determined?

Female mice were treated for 35 days from birth to 60 days postnatal (P0, [birth], P5, P10, P20 and adult [∼P60]) with dihydrotestosterone (DHT). Such treatment elicited profound masculinization the female external genitalia and development of penile features (penile spines, male urogenital mating protuberance (MUMP) cartilage, corpus cavernosum glandis, corporal body, MUMP-corpora cavernosa, a large preputial space, internal preputial space, os penis). Time course studies demonstrated that DHT elicited canalization of the U-shaped clitoral lamina to create a U-shaped preputial space, preputial lining epithelium and penile epithelium adorned with spines. The effect of DHT was likely due to signaling through androgen receptors normally present postnatally in the clitoral lamina and associated mesenchyme. This study highlights a remarkable male/female difference in specification and determination of urogenital organ identity. Urogenital organ identity in male mice is irreversibly specified and determined prenatally (prostate, penis, and seminal vesicle), whereas many aspects of the female urogenital organogenesis are not irreversibly determined at birth and in the case of external genitalia are not irreversibly determined even into adulthood, the exception being positioning of the female urethra, which is determined prenatally.

Microscopic Features of Vaginectomy Specimens from Transgender Patients

OBJECTIVES

We aimed to better understand the histologic changes in vaginectomy specimens in transgender and gender-diverse (TGD) individuals after prolonged androgen administration.

METHODS

After obtaining institutional review board approval, we reviewed clinical records for all TGD individuals who underwent vaginal tissue resection at our institution between January 2002 and July 2020.

RESULTS

Ten transgender males who underwent vaginectomy for gender affirmation were identified. All patients had been assigned female gender at birth, and the median age at surgery was 41 years (range, 22-74 years). All 10 patients had received androgen for 2 to 10 years preoperatively. The corresponding pathology specimens were examined grossly and microscopically, including with immunohistochemical stains for NKX3.1, prostate-specific antigen (PSA), p501s, and androgen receptor (AR). No gross lesions were identified. Microscopically, prostate-like glands (8/10), urothelial metaplasia (4/10), and vaginal atrophy (8/10) were identified. Seven cases with prostate-like glands showed positive staining with PSA, NKX3.1, p501s, and AR in both squamous and glandular components.

CONCLUSIONS

Recognition of these androgen-related changes enables pathologist to avoid the overdiagnosis of dysplasia. Long-term follow-up is needed to thoroughly understand any potential future implications of these androgen-related changes.

Precision Targets for Intercepting the Lethal Progression of Prostate Cancer: Potential Avenues for Personalized Therapy

Organ-confined prostate cancer of low-grade histopathology is managed with radiation, surgery, active surveillance, or watchful waiting and exhibits a 5-year overall survival (OS) of 95%, while metastatic prostate cancer (PCa) is incurable, holding a 5-year OS of 30%. Treatment options for advanced PCa-metastatic and non-metastatic-include hormone therapy that inactivates androgen receptor (AR) signaling, chemotherapy and genome-targeted therapy entailing synthetic lethality of tumor cells exhibiting aberrant DNA damage response, and immune checkpoint inhibition (ICI), which suppresses tumors with genomic microsatellite instability and/or deficient mismatch repair. Cancer genome sequencing uncovered novel somatic and germline mutations, while mechanistic studies are revealing their pathological consequences. A microRNA has shown biomarker potential for stratifying patients who may benefit from angiogenesis inhibition prior to ICI. A 22-gene expression signature may select high-risk localized PCa, which would not additionally benefit from post-radiation hormone therapy. We present an up-to-date review of the molecular and therapeutic aspects of PCa, highlight genomic alterations leading to AR upregulation and discuss AR-degrading molecules as promising anti-AR therapeutics. New biomarkers and druggable targets are shaping innovative intervention strategies against high-risk localized and metastatic PCa, including AR-independent small cell-neuroendocrine carcinoma, while presenting individualized treatment opportunities through improved design and precision targeting.

Prostatic metaplasia of the vagina in transmasculine individuals

PURPOSE

To determine the prevalence of prostatic metaplasia in an expanded cohort of transmasculine individuals undergoing gender-affirming resection of vaginal tissue.

METHODS

Institutional Review Board approval was obtained. Clinical records were reviewed for all transmasculine individuals undergoing vaginal tissue resection at our institution between January 2018 and July 2021. Corresponding pathology specimens were examined grossly and microscopically, including immunohistochemical stains for NKX3.1, prostate-specific antigen (PSA), and androgen receptor (AR). Vaginal specimens from three patients without androgen supplementation were used as controls.

RESULTS

Twenty-one patients met inclusion criteria. The median age at surgery was 26.4 years (range 20.6-34.5 years). All patients had been assigned female gender at birth and lacked endocrine or genetic abnormalities. All were on testosterone therapy; median duration of therapy at surgery was 4.4 years (range 1.4-12.1 years). In the transmasculine group, no gross lesions were identified. Microscopically, all specimens demonstrated patchy intraepithelial glandular proliferation along the basement membrane and/or nodular proliferation of prostate-type tissue within the subepithelial stroma. On immunohistochemical staining, performed for a subset of cases, the glandular proliferation was positive for NKX3.1 (16/16 cases; 100%), PSA (12/14 cases; 85.7%), and AR (8/8 cases; 100%). Controls showed no evidence of prostatic metaplasia.

CONCLUSION

One hundred percent of vaginal specimens obtained from transmasculine individuals on testosterone therapy (21/21 cases) demonstrated prostatic metaplasia. Further investigation is warranted to characterize the natural history and clinical significance of these changes. Patients seeking hormone therapy and/or gender-affirming surgery should be counseled on the findings and their yet-undetermined significance.

A Review of Prostate Organogenesis and a Role for iPSC-Derived Prostate Organoids to Study Prostate Development and Disease

The prostate is vulnerable to two major age-associated diseases, cancer and benign enlargement, which account for significant morbidity and mortality for men across the globe. Prostate cancer is the most common cancer reported in men, with over 1.2 million new cases diagnosed and 350,000 deaths recorded annually worldwide. Benign prostatic hyperplasia (BPH), characterised by the continuous enlargement of the adult prostate, symptomatically afflicts around 50% of men worldwide. A better understanding of the biological processes underpinning these diseases is needed to generate new treatment approaches. Developmental studies of the prostate have shed some light on the processes essential for prostate organogenesis, with many of these up- or downregulated genes expressions also observed in prostate cancer and/or BPH progression. These insights into human disease have been inferred through comparative biological studies relying primarily on rodent models. However, directly observing mechanisms of human prostate development has been more challenging due to limitations in accessing human foetal material. Induced pluripotent stem cells (iPSCs) could provide a suitable alternative as they can mimic embryonic cells, and iPSC-derived prostate organoids present a significant opportunity to study early human prostate developmental processes. In this review, we discuss the current understanding of prostate development and its relevance to prostate-associated diseases. Additionally, we detail the potential of iPSC-derived prostate organoids for studying human prostate development and disease.

Human urogenital sinus mesenchyme is an inducer of prostatic epithelial development

OBJECTIVE

To determine whether human fetal urogenital sinus mesenchyme (UGM) can induce prostatic development in a responsive mouse epithelium.

METHOD

Male and female human fetal UGM was combined with mouse urinary bladder epithelium (BLE), and the resultant human UGM + mouse BLE tissue recombinants were grown under renal capsules of male athymic mice. Human male and female UGM was derived from reproductive tracts 9 and 14 weeks of gestation obtained following elective termination of pregnancy. At these ages prostatic ducts had already emerged from the urogenital sinus epithelium, and the human UGM remained contaminated with human prostatic epithelium. This unavoidable problem was tolerated because the induced mouse prostatic epithelium could be distinguished from contaminating human prostatic epithelium.

RESULTS

The simple columnar epithelium induced from mouse bladder epithelium by human male and female UGM resembled mouse prostatic epithelium by: (a) histology, (b) the pattern of basal cell distribution, (c) Hoechst dye nuclear staining, (d) expression of NKX3.1, (e) the pattern of androgen receptor expression and (f) the expression of probasin, a mouse prostatic secretory protein. Summary/Interpretation: These findings provide validation for mouse as a model of human prostatic development as the molecular dialogue involved in mesenchymal-epithelial interactions are sufficiently conserved that human UGM can induce mouse bladder epithelium to undergo prostatic development.