Preclinical study for treatment of hypospadias by advanced therapy medicinal products

Urine-derived exosomes and their role in modulating uroepithelial cells to prevent hypospadias

PURPOSE

Urethral hypospadias, a common congenital malformation in males, is closely linked with disruptions in uroepithelial cell (UEC) processes. Evidence exists reporting that urine-derived exosomes (Urine-Exos) enhance UEC proliferation and regeneration, suggesting a potential role in preventing hypospadias. However, the specific influence of Urine-Exos on urethral hypospadias and the molecular mechanisms involved are not fully understood. This study focuses on investigating the capability of Urine-Exos to mitigate urethral hypospadias and aims to uncover the underlying molecular mechanisms.

METHODS

Bioinformatics analysis was performed to identify key gene targets in Urine-Exos potentially involved in hypospadias. Subsequent in vitro and in vivo experiments were conducted to validate the regulatory effects of Urine-Exos on hypospadias.

RESULTS

Bioinformatics screening revealed syndecan-1 (SDC1) as a potential pivotal gene for the prevention of hypospadias. In vitro experiments demonstrated that Urine-Exos enhanced the proliferation and migration of UECs by transferring SDC1 and inhibiting cell apoptosis. Notably, Urine-Exos upregulated β-catenin expression through SDC1 transfer, further promoting UEC proliferation and migration. These findings were confirmed in a congenital hypospadias rat model induced by di(2-ethylhexyl) phthalate (DEHP).

CONCLUSION

This study reveals the therapeutic potential of Urine-Exos in hypospadias, mediated by the SDC1/β-catenin axis. Urine-Exos promote UEC proliferation and migration, thereby inhibiting the progression of hypospadias. These findings offer new insights and potential therapeutic targets for the management of congenital malformations.

Validation of airway porcine epithelial cells as an alternative to human in vitro preclinical studies

Animal models are currently used in several fields of biomedical research as useful alternatives to human-based studies. However, the obtained results do not always effectively translate into clinical applications, due to interspecies anatomical and physiological differences. Detailed comparability studies are therefore required to verify whether the selected animal species could be a representative model for the disease or for cellular process under investigation. This has proven to be fundamental to obtaining reliable data from preclinical studies. Among the different species, swine is deemed an excellent animal model in many fields of biological research, and has been largely used in respiratory medicine, considering the high homology between human and swine airways. In the context of in vitro studies, the validation of porcine airway epithelial cells as an alternative to human epithelial cells is crucial. In this paper, porcine and human tracheal and bronchial epithelial cells are compared in terms of in vivo tissue architecture and in vitro cell behaviour under standard and airlifted conditions, analyzing the regenerative, proliferative and differentiative potentials of these cells. We report multiple analogies between the two species, validating the employment of porcine airway epithelial cells for most in vitro preclinical studies, although with some limitations due to species-related divergences.

Comparison between Cultivated Oral Mucosa and Ocular Surface Epithelia for COMET Patients Follow-Up

Total bilateral Limbal Stem Cell Deficiency is a pathologic condition of the ocular surface due to the loss of corneal stem cells. Cultivated oral mucosa epithelial transplantation (COMET) is the only autologous successful treatment for this pathology in clinical application, although abnormal peripheric corneal vascularization often occurs. Properly characterizing the regenerated ocular surface is needed for a reliable follow-up. So far, the univocal identification of transplanted oral mucosa has been challenging. Previously proposed markers were shown to be co-expressed by different ocular surface epithelia in a homeostatic or perturbated environment. In this study, we compared the transcriptome profile of human oral mucosa, limbal and conjunctival cultured holoclones, identifying Paired Like Homeodomain 2 (PITX2) as a new marker that univocally distinguishes the transplanted oral tissue from the other epithelia. We validated PITX2 at RNA and protein levels to investigate 10-year follow-up corneal samples derived from a COMET-treated aniridic patient. Moreover, we found novel angiogenesis-related factors that were differentially expressed in the three epithelia and instrumental in explaining the neovascularization in COMET-treated patients. These results will support the follow-up analysis of patients transplanted with oral mucosa and provide new tools to understand the regeneration mechanism of transplanted corneas.

SOX2 Is a Univocal Marker for Human Oral Mucosa Epithelium Useful in Post-COMET Patient Characterization

Total bilateral Limbal Stem Cells Deficiency is a pathologic condition of the ocular surface due to loss or impairment of corneal stem cell function, altering homeostasis of the corneal epithelium. Cultivated Oral Mucosa Epithelial Transplantation (COMET) is the only autologous treatment for this pathology. During the follow-up, a proper characterization of the transplanted oral mucosa on the ocular surface supports understanding the regenerative process. The previously proposed markers for oral mucosa identification (e.g., keratins 3 and 13) are co-expressed by corneal and conjunctival epithelia. Here, we propose a new specific marker to distinguish human oral mucosa from the epithelia of the ocular surface. We compared the transcriptome of holoclones (stem cells) from the human oral mucosa, limbal and conjunctival cultures by microarray assay. High expression of SOX2 identified the oral mucosa vs. cornea and conjunctiva, while PAX6 was highly expressed in corneal and conjunctival epithelia. The transcripts were validated by qPCR, and immunological methods identified the related proteins. Finally, the proposed markers were used to analyze a 10-year follow-up aniridic patient treated by COMET. These findings will support the follow-up analysis of COMET treated patients and help to shed light on the mechanism of corneal repair and regeneration.

Regenerative Medicine of Epithelia: Lessons From the Past and Future Goals

This article explores examples of successful and unsuccessful regenerative medicine on human epithelia. To evaluate the applications of the first regenerated tissues, the analysis of the past successes and failures addresses some pending issues and lay the groundwork for developing new therapies. Research should still be encouraged to fill the gap between pathologies, clinical applications and what regenerative medicine can attain with current knowledge.

Intrasphincteric anastomotic urethroplasty allows preservation of continence in men with bulbomembranous urethral strictures following benign prostatic hyperplasia surgery

PURPOSE

Injury to the external sphincter during urethroplasty at or near the membranous urethra can result in incontinence in men whose internal sphincter mechanism has been compromised by previous benign prostatic hyperplasia (BPH) surgery. We present outcomes of a novel reconstructive procedure, incorporating a recent anatomic discovery revealing a connective tissue sheath between the external sphincter and membranous urethra, which provides a surgical plane allowing for intrasphincteric bulbo-prostatic urethroplasty (ISBPA) with continence preservation.

METHODS

Stricture at or near the membranous urethra after transurethral resection (TURP) or open simple prostatectomy (OSP) was reconstructed with ISBPA. The bulbomembranous junction is approached dorsally with a bulbar artery sparing approach and the external sphincter muscle is carefully reflected, exposing the wall of the membranous urethra. Gentle blunt dissection along this connective tissue plane allows separating the muscle away up to the prostatic apex, where healthy urethra is found for anastomosis.

RESULTS

From January 2010 to August 2019, 40 men (18 after TURP and 22 after OSP) underwent ISBPA at a single institution. Mean age was 67 years (54-82). Mean stricture length was 2.6 cm (1-6) with obliterative stricture identified in 10 (25%). At a mean follow-up of 53 months (10-122), 36 men (90%) are free of stricture recurrence and 34 (85%) were completely dry or using one security pad.

CONCLUSION

This novel intrasphincteric urethroplasty technique for stricture following BPH surgery is feasible and safe, allowing successful reconstruction with continence preservation in most patients. A larger series and reproduction in other centers is needed.

Non-transecting bulbar urethroplasty is favored over transecting techniques

PURPOSE

To present current evidence supporting the vessel sparing technique to reconstruct bulbar urethral strictures via primary anastomosis.

METHODS

English literature review of presented series of transecting and non-transecting bulbar urethroplasty from 2000 to 2018.

RESULTS

Since its introduction in 2007, vessel-sparing excision and primary anastomosis (VS-EPA) has been utilized in multiple centers across the world. Success rates range from 90 to 98%, comparable to traditional transecting EPA. Complication rates and erectile function outcomes are similar or better in VS-EPA, according to recent publications.

CONCLUSIONS

Non-transection excision and primary anastomosis is a well-tolerated, highly successful reconstructive option for short bulbar urethral strictures in appropriately selected patients. Results are comparable with traditional transecting anastomosis and mid-term multinational follow-up has proven efficacy and safety of the technique. Further well-designed multi-institutional studies are necessary to determine superiority to traditional EPA in terms of surgical outcomes and erectile function preservation.