Immunohistochemical profile of the penile urethra and differential expression of GATA3 in urothelial versus squamous cell carcinomas of the penile urethra

Comparing an Integrated Amphiphilic Surfactant to Traditional Hydrophilic Coatings for the Reduction of Catheter-Associated Urethral Microtrauma

Hydrophilic-coated intermittent catheters have improved the experience of intermittent urinary catheterization for patients compared to conventional gel-lubricated uncoated catheters. However, the incorporation of polyvinylpyrrolidone (PVP) within hydrophilic coatings can lead to significant issues with coating dry-out. Consequently, increased force on catheter withdrawal may cause complications, including urethral microtrauma and pain. Standard methods of evaluating catheter lubricity lack physiological relevance and an understanding of the surface interaction with the urethra. The tribological performance and urethral interaction of commercially available hydrophilic PVP-coated catheters and a coating-free integrated amphiphilic surfactant (IAS) catheter were evaluated by using a biomimetic urethral model designed from a modified coefficient of friction (CoF) assay. T24 human urothelial cells were cultured on customized silicone sheets as an alternate countersurface for CoF testing. Hydrophilic PVP-coated and coating-free IAS catheters were hydrated and the CoF obtained immediately following hydration, or after 2 min, mimicking in vivo indwell time for urine drainage. The model was observed for urethral epithelial cell damage postcatheterization. The majority of hydrophilic PVP-coated catheters caused significantly greater removal of cells from the monolayer after 2 min indwell time, compared to the IAS catheter. Hydrophilic PVP-coated catheters were shown to cause more cell damage than the coating-free IAS catheter. A biomimetic urethral model provides a more physiologically relevant model for understanding the factors that govern the frictional interface between a catheter surface and urethral tissue. From these findings, the use of coating-free IAS catheters instead of hydrophilic PVP-coated catheters may help reduce urethral microtrauma experienced during catheter withdrawal from the bladder, which may lead to a lower risk of infection.

Occult urothelial carcinoma with mediastinal metastasis: A case report

Occult urothelial carcinoma (UC), particularly with mediastinal metastases, is an uncommon clinical occurrence. The present study describes the unusual case of a 70-year-old male patient who developed mediastinal metastases from an occult UC. Histological evaluations and immunohistochemical features of the mediastinal tumor were indicative of UC; however, extensive imaging failed to identify the primary urological lesion. The findings suggest that mediastinal metastases from UCs, despite their rarity, should be considered in cases where patients with mediastinal tumors exhibit chest-related symptoms. Prompt pathological examinations are crucial for ascertaining the nature and origin of the tumor. Moreover, individualized treatment should be performed in strict accordance with the established oncology guidelines.

Fibroepithelial urethral polyp with minor prostatic glands in an older man

We describe a man in his 60s with an incidentally detected urethral polyp located in the middle section of his penile shaft. The patient had been suffering from urinary retention for 9 years due to benign prostatic hyperplasia. He was initiated on clean intermittent catheterisation to drain urine 1 year before the detection of the urethral polyp. Holmium laser nucleation of the prostate was performed, and an anterior urethral polyp (5 mm in diameter) was resected. Pathology indicated that the urethral polyp was a fibroepithelial polyp with prostate-specific antigen-immunoreactive heterotopic prostatic glands. There were no problems with urination 6 months after surgery. Fibroepithelial urethral polyps are usually congenital and are rarely described in adults. The clinicopathological features of this polyp, with its uniquely associated minor prostatic glands, are presented.

Downregulation of MicroRNA-494 inhibits the TGF-β1/Smads signaling pathway and prevents the development of hypospadias through upregulating Nedd4L

BACKGROUND

Hypospadias, as a congenital disorder of the urethra, is the second most common birth abnormality of the male reproductive system. This study primarily investigates the effects of microRNA-494 (miR-494) on the transforming growth factor-β1 (TGF-β1)/Smads signaling pathway and on the development of hypospadias by binding to neural precursor cell expressed developmentally downregulated gene 4-like (Nedd4L).

METHODS

We induced a mouse model of hypospadias through di-(2-ethylhexyl) phthalate treatment. The underlying regulatory mechanisms of miR-494 in this model were analyzed upon treatment of miR-494 mimic, miR-494 inhibitor, or small interfering RNA against Nedd4L in urethral epithelial cells isolated from mice with hypospadias. We then verified the binding site between miR-494 and Nedd4L and applied a gain- and loss-of-function approach to determine the effects of miR-494 on cell proliferation, cycle distribution, and apoptosis.

RESULTS

Male mice with hypospadias exhibited significantly higher miR-494 expression and lower Nedd4L expression in urethral tissues than normal male mice. Nedd4L was verified as a target gene of miR-494. Treatment with miR-494 inhibitor suppressed the activation of the TGF-β1/Smads signaling pathway, whereas down-regulation of miR-494 exerted protective effects on urethral epithelial cells by impeding cell proliferation and inducing cell apoptosis.

CONCLUSIONS

The study indicates that downregulation of miR-494 inhibits the TGF-β1/Smads signaling pathway and prevents the development of hypospadias through upregulating Nedd4L.

Primary transitional cell carcinoma of penis - A rare presentation

Primary transitional cell carcinoma arising from the anterior portion of the male urethra is rare, with no recent cases reported in the literature. We present a case of penile TCC with positive urine cytology and a delayed definitive diagnosis.

Synergistic effect of siRNA-mediated silencing of TGF-β R1 and TGF-β R2 genes on the proliferation and apoptosis of penile urethral epithelial cells in hypospadiac male rats

The study elucidated the effects associated with silencing growth factor-β R1 (TGF-β R1) and TGF-β R2 genes on the proliferation and apoptosis of penile urethral epithelial cells (UECs) in hypospadiac male rats. Seventy-five male rats were distributed into the normal, model, TGF-β R1/2-siRNA, TGF-β R1-siRNA and TGF-β R2-siRNA groups. The UECs of the rats included in the study were cultured in vitro and subsequently divided into the control, blank, TGF-β R1/2-siRNA, TGF-β R1-siRNA and TGF-β R2-siRNA groups. The mRNA and protein expressions of TGF-β R1/R2 were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting. Cell proliferation and apoptosis were evaluated by cell counting kit-8 (CCK-8) assay as well as by flow cytometry. Compared with the normal group, the apoptotic rate of the UECs in the model, TGF-β R1/2-siRNA, TGF-β R1-siRNA and TGF-β R2-siRNA groups displayed remarkable increases; compared with the model group, the apoptotic rate of the UECs in the TGF-β R1/2-siRNA, TGF-β R1-siRNA and TGF-β R2-siRNA groups displayed significant decreases, similar observations were made regarding mRNA and protein expressions of TGF-β R1 and TGF-β R2. Compared with the TGF-β R1/2-siRNA group, the apoptotic rates of the UECs in the TGF-β R1-siRNA and TGF-β R2-siRNA groups were up regulated, while cell proliferation in the TGF-β R1-siRNA and TGF-β R2-siRNA groups decreased accompanied by an increased rate of apoptosis. This study ultimately demonstrated that the silencing of TGF-β R1 and TGF-β R2 genes could promote cell proliferation and inhibit apoptosis of penile UECs in hypospadiac male rats.

Urethral carcinoma in situ: recognition and management

PURPOSE

Urethral carcinoma in situ (CIS) is an uncommon malignancy that is poorly described in the published literature and is often under-recognized in the clinical setting. This short case series reports some challenges associated with the recognition and management of this disease.

METHODS

A retrospective chart review was done over a 12-year period of patients presenting with urethral cancer to the Johns Hopkins Hospital. Four patients were identified with CIS of the anterior urethra, and their demographic and clinical data were recorded.

RESULTS

Three patients presented with meatal lesions that were initially treated as infectious/inflammatory diseases before diagnoses of malignancy were determined following lesion biopsy. The fourth patient presented with painless hematuria and had a cystoscopy and biopsy of urethral polyps. All patients were treated surgically by sequential distal urethrectomy and various reconstructive procedures. Concurrent lymph node dissections were undertaken in two patients who had clinical or radiologic evidence of lymphadenopathy. One patient had persistent disease even after aggressive urethral resection, and he succumbed to his illness 2 years later.

CONCLUSION

This is the largest series of urethral CIS, a disease with potentially serious consequences. A high index of suspicion should be maintained when evaluating and managing these patients.

Cutaneous squamous cell carcinoma progression is associated with decreased GATA-3 immunohistochemical staining

BACKGROUND

The GATA family of transcription factors is an essential regulator of cellular proliferation and differentiation. In the skin, GATA-3 is critical for epidermal stratification and maintenance of barrier function. A role for GATA-3 in the development of human cutaneous squamous cell carcinoma (SCC) is not known. Here, we investigated GATA-3 immunohistochemical staining in premalignant and invasive cutaneous SCC from sun-exposed and sun-protected skin.

METHODS

GATA-3 immunohistochemistry was performed on actinic keratoses (AK) (n = 19), in situ squamous cell carcinomas with actinic [SCCIS (A)] (n = 9) or bowenoid features [SCCIS (B)] (n = 17), well-, moderately and poorly differentiated SCC (n = 36), Bowenoid papulosis of the perineum (n = 15) and penile SCC (pSCC) (n = 10).

RESULTS

We found that GATA-3 immunohistochemical staining is progressively lost in sun-exposed skin as neoplasia progresses from pre-cancerous AK to SCCIS (A), and ultimately, to SCC, which shows near absent GATA-3 staining. This reduction in GATA-3 staining is independent of histological grade in SCC. Only slight down-regulation of GATA-3 was seen in all cases of SCCIS (B) and Bowenoid papulosis, while near absent GATA-3 expression was seen in pSCC.

CONCLUSION

We propose that decreased GATA-3 immunohistochemical staining is associated with cutaneous SCC progression on both sun-exposed and sun-protected sites.

GATA-3 expression in trophoblastic tissues: an immunohistochemical study of 445 cases, including diagnostic utility

Immunohistochemical expression of GATA-3 is seen predominantly in non-neoplastic bladder and breast epithelium and their respective carcinomas; however, data on expression in normal and lesional trophoblastic tissues are limited. Immunohistochemical staining for GATA-3 was assessed in a range of normal/lesional trophoblastic tissues and tumors in the differential diagnosis (n=445), including nonmolar products of conceptions/second and third trimester placentas/ectopic pregnancies, hydatidiform moles, placental site nodules, normal/exaggerated implantation sites, choriocarcinomas, epithelioid trophoblastic tumors, placental site trophoblastic tumors, atypical smooth muscle tumors (including leiomyosarcoma), and cervical and pulmonary squamous cell carcinomas. The extent of expression (0 to 4+) and intensity (weak to strong) were recorded. All cases with developing trophoblast/non-neoplastic trophoblastic proliferation and 81% of trophoblastic neoplasms were positive. Of all non-neoplastic trophoblast cell types, expression was observed in cytotrophoblast in 89% of cases, syncytiotrophoblast in 50%, intermediate trophoblast in 100%, and villous trophoblastic columns in 100%. Increasing gestational age was associated with a decrease in extent/intensity of expression in non-neoplastic cytotrophoblast and syncytiotrophoblast, whereas intermediate trophoblast maintained diffuse and strong expression from early to late gestation (P<0.0001). Eighty-nine percent of normal/exaggerated implantation sites showed 3+ or 4+ expression, whereas staining in 55% of placental site nodules was 1+ or 2+. Staining for GATA-3 was present in 78% of choriocarcinomas, 95% of epithelioid trophoblastic tumors, and 71% of placental site trophoblastic tumors. Although the number of choriocarcinomas and placental site trophoblastic tumors that showed a spectrum of expression ranging from negative to diffuse was relatively evenly distributed, 81% of epithelioid trophoblastic tumors had 3+ or 4+ staining. None of the atypical smooth muscle tumors and 3% of squamous cell carcinomas were positive, all of which exhibited weak staining. We conclude that GATA-3 is frequently expressed in normal and lesional trophoblastic tissues. It is also differentially expressed in intermediate trophoblast and cytotrophoblast/syncytiotrophoblast, which varies according to time during pregnancy. This study expands the spectrum of neoplasms known to express GATA-3. Thus, recognition of expression in trophoblastic tumors is important, because it can present a diagnostic pitfall in the assessment of suspected metastatic bladder or breast carcinomas involving the gynecologic tract. In the evaluation of diagnostically problematic tumors for which trophoblastic neoplasms are in the differential diagnosis, such as leiomyosarcoma and squamous cell carcinoma, GATA-3 can be included as part of an immunohistochemical panel particularly when other trophoblastic markers are either not available or yield ambiguous results.

Clinicopathological features of carcinoma of the distal penile urethra

Distal urethral carcinomas are very rare and are similar in their pathology and behaviour to tumours of the glans penis and foreskin. Similarly they are associated with penile intraepithelial neoplasia (PeIN) of both differentiated and undifferentiated types. Current management is mainly surgical, but increasingly involves specialist penile-preserving techniques. Handling and dissection of the specimens is broadly the same as other primary penile tumours. The prognosis of distal urethral lesions is believed to be worse than penile tumours and better than prostatic urethral tumours, but the evidence is sparse. The staging system for urethral tumours does not distinguish between proximal and distal, apart from prostatic urethra, and has led to much confusion in the literature. Although the subtypes of tumours seen in the distal urethra are the same as those on the glans and foreskin, there is an increased proportion of basaloid squamous carcinoma and malignant melanoma whereas the majority of tumours seen in the proximal and prostatic urethra are of urothelial origin. In future, distal urethral tumours should be separately designated with site-specific staging/TNM and reporting system and pathologically classified in the same way as penile and foreskin tumours. Ultimately, this will improve the quality of data and produce evidence to inform management.