Current Status of Tissue Engineering in the Management of Severe Hypospadias

Abstract

Hypospadias, characterized by misplacement of the urinary meatus in the lower side of the penis, is a frequent birth defect in male children. Because of the huge variation in the anatomic presentation of hypospadias, no single urethroplasty procedure is suitable for all situations. Hence, many surgical techniques have emerged to address the shortage of tissues required to bridge the gap in the urethra particularly in the severe forms of hypospadias. However, the rate of postoperative complications of currently available surgical procedures reaches up to one-fourth of the patients having severe hypospadias. Moreover, these urethroplasty techniques are technically demanding and require considerable surgical experience. These limitations have fueled the development of novel tissue engineering techniques that aim to simplify the surgical procedures and to reduce the rate of complications. Several types of biomaterials have been considered for urethral repair, including synthetic and natural polymers, which in some cases have been seeded with cells prior to implantation. These methods have been tested in preclinical and clinical studies, with variable degrees of success. This review describes the different urethral tissue engineering methodologies, with focus on the approaches used for the treatment of hypospadias. At present, despite many significant advances, the search for a suitable tissue engineering approach for use in routine clinical applications continues.

The impact of COL1A1 and COL6A1 expressions on hypospadias and penile curvature severity

“…We also investigated the statistical difference of COL1A1 and COL6A1 expressions among groups based on penile curvature in the hypospadias group. Mostly, severe forms of hypospadias are related to a signi cant chordee and a urethral meatus located proximal to the midshaft of the penis (18). Another study proposed that severity of chordee is generally proportional to the degree of hypospadias (19).…”

The impact of COL1A1 and COL6A1 expressions on hypospadias and penile curvature severity

“…We also investigated the statistical difference of COL1A1 and COL6A1 expressions among groups based on penile curvature in hypospadias group. Mostly, severe forms of hypospadias are related to a signi cant chordee and a urethral meatus located proximal to the midshaft of the penis (18). Another study proposed that severity of chordee is generally proportional to the degree of hypospadias (19).…”

From Acellular Matrices to Smart Polymers: Degradable Scaffolds that are Transforming the Shape of Urethral Tissue Engineering

“…However, these synthetic polymers have limited biocompatibility because they lack specific molecular elements for interaction with cells and proteins, usually requiring surface treatments to promote cell attachment [54]. Comprehensive reviews of the different biomaterials used in urethral tissue engineering are available elsewhere [12,13,55,56]. While these approaches, in general, have a goal to mimic the properties of the urethra to recover complete function, they have not been able to achieve this goal.…”

“…Urethral tissue engineering has recently emerged as a viable alternative to overcome the issues associated with autologous grafts [12]. In addition to eliminating the need of harvesting autologous tissue, tissue engineered solutions are expected to become “off-the-shelf” products in the future [13].…”