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Germ cell development in the postnatal testis: the key to prevent malignancy in cryptorchidism?

Hutson JM, Li R, Southwell BR, Petersen BL, Thorup J, Cortes D - Front Endocrinol (Lausanne) (2013)

Bottom Line: Failure of any part of this process leads to congenital cryptorchidism, wherein the malpositioned testis finds itself at the wrong temperature after birth, which leads to secondary germ cell loss and later infertility and risk of cancer.Recent studies suggest that neonatal gonocytes transform into the putative spermatogenic stem cells between 3 and 9 months, and this initial postnatal step is deranged in cryptorchid testes.In addition, it is thought the abnormality high temperature may also impair apoptosis of remaining gonocytes, allowing some to persist to become the possible source of carcinoma in situ and malignancy after puberty.

View Article: PubMed Central - PubMed

Affiliation: Department of Urology, Royal Children's Hospital Parkville, VIC, Australia.

ABSTRACT
To permit normal postnatal germ cell development, the mammalian testis undergoes a complex, multi-staged process of descent to the scrotum. Failure of any part of this process leads to congenital cryptorchidism, wherein the malpositioned testis finds itself at the wrong temperature after birth, which leads to secondary germ cell loss and later infertility and risk of cancer. Recent studies suggest that neonatal gonocytes transform into the putative spermatogenic stem cells between 3 and 9 months, and this initial postnatal step is deranged in cryptorchid testes. In addition, it is thought the abnormality high temperature may also impair apoptosis of remaining gonocytes, allowing some to persist to become the possible source of carcinoma in situ and malignancy after puberty. The biology of postnatal germ cell development is of intense interest, as it is likely to be the key to the optimal timing for orchidopexy.

No MeSH data available.


Related in: MedlinePlus

Testicular descent. (A) Cranial suspensory ligament (CSL) and gubernaculum (G) hold the testis. Testosterone (T) and MIS/AMH act on Wolffian duct (WD) and Müllerian duct (MD). (B) Insulin 3 (Insl3) causes the gubernacular swelling reaction that holds the testis near the groin during midgestational growth (8–15 weeks). (C) Calcitonin gene-related peptide (CGRP) released by the genitofemoral nerve, and under the control of testosterone, steers the migrating gubernaculum to the scrotum.
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Figure 1: Testicular descent. (A) Cranial suspensory ligament (CSL) and gubernaculum (G) hold the testis. Testosterone (T) and MIS/AMH act on Wolffian duct (WD) and Müllerian duct (MD). (B) Insulin 3 (Insl3) causes the gubernacular swelling reaction that holds the testis near the groin during midgestational growth (8–15 weeks). (C) Calcitonin gene-related peptide (CGRP) released by the genitofemoral nerve, and under the control of testosterone, steers the migrating gubernaculum to the scrotum.

Mentions: At 5 weeks of gestation, embryonic gonocytes migrate from the umbilical stalk into the ambisexual gonad. Human sexual development then begins at 7–8 weeks’ gestation when the SRY (sex-determining region Y) gene initiates testicular differentiation with Sertoli cell development (Sinclair, 1994). Cords of Sertoli cells surround the newly arrived germ cells and the interstitial cells form Leydig cells and peritubular myoid cells. Müllerian-inhibiting substance (or anti-Müllerian hormone) (MIS/AMH) and testosterone synthesis by Sertoli cells and Leydig cells, respectively, trigger regression of Müllerian ducts and preservation of Wolffian ducts which form epididymis, vas, and seminal vesicles (Wilson et al., 1981; Lee and Donahoe, 1993; Figure 1). The intra-abdominal fetal testis descends to the scrotum in a complex, two-stage process that in humans is complete at birth, while in rodents the second phase occurs in the first week after birth (Hutson et al., 1997). The regulation of this two-stage process is not the subject of this review, but interested readers should see some recent reviews (Ivell and Hartung, 2003; Adham and Agoulnik, 2004; Amann and Veeramachaneni, 2007; Bay et al., 2011).


Germ cell development in the postnatal testis: the key to prevent malignancy in cryptorchidism?

Hutson JM, Li R, Southwell BR, Petersen BL, Thorup J, Cortes D - Front Endocrinol (Lausanne) (2013)

Testicular descent. (A) Cranial suspensory ligament (CSL) and gubernaculum (G) hold the testis. Testosterone (T) and MIS/AMH act on Wolffian duct (WD) and Müllerian duct (MD). (B) Insulin 3 (Insl3) causes the gubernacular swelling reaction that holds the testis near the groin during midgestational growth (8–15 weeks). (C) Calcitonin gene-related peptide (CGRP) released by the genitofemoral nerve, and under the control of testosterone, steers the migrating gubernaculum to the scrotum.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3539691&req=5

Figure 1: Testicular descent. (A) Cranial suspensory ligament (CSL) and gubernaculum (G) hold the testis. Testosterone (T) and MIS/AMH act on Wolffian duct (WD) and Müllerian duct (MD). (B) Insulin 3 (Insl3) causes the gubernacular swelling reaction that holds the testis near the groin during midgestational growth (8–15 weeks). (C) Calcitonin gene-related peptide (CGRP) released by the genitofemoral nerve, and under the control of testosterone, steers the migrating gubernaculum to the scrotum.
Mentions: At 5 weeks of gestation, embryonic gonocytes migrate from the umbilical stalk into the ambisexual gonad. Human sexual development then begins at 7–8 weeks’ gestation when the SRY (sex-determining region Y) gene initiates testicular differentiation with Sertoli cell development (Sinclair, 1994). Cords of Sertoli cells surround the newly arrived germ cells and the interstitial cells form Leydig cells and peritubular myoid cells. Müllerian-inhibiting substance (or anti-Müllerian hormone) (MIS/AMH) and testosterone synthesis by Sertoli cells and Leydig cells, respectively, trigger regression of Müllerian ducts and preservation of Wolffian ducts which form epididymis, vas, and seminal vesicles (Wilson et al., 1981; Lee and Donahoe, 1993; Figure 1). The intra-abdominal fetal testis descends to the scrotum in a complex, two-stage process that in humans is complete at birth, while in rodents the second phase occurs in the first week after birth (Hutson et al., 1997). The regulation of this two-stage process is not the subject of this review, but interested readers should see some recent reviews (Ivell and Hartung, 2003; Adham and Agoulnik, 2004; Amann and Veeramachaneni, 2007; Bay et al., 2011).

Bottom Line: Failure of any part of this process leads to congenital cryptorchidism, wherein the malpositioned testis finds itself at the wrong temperature after birth, which leads to secondary germ cell loss and later infertility and risk of cancer.Recent studies suggest that neonatal gonocytes transform into the putative spermatogenic stem cells between 3 and 9 months, and this initial postnatal step is deranged in cryptorchid testes.In addition, it is thought the abnormality high temperature may also impair apoptosis of remaining gonocytes, allowing some to persist to become the possible source of carcinoma in situ and malignancy after puberty.

View Article: PubMed Central - PubMed

Affiliation: Department of Urology, Royal Children's Hospital Parkville, VIC, Australia.

ABSTRACT
To permit normal postnatal germ cell development, the mammalian testis undergoes a complex, multi-staged process of descent to the scrotum. Failure of any part of this process leads to congenital cryptorchidism, wherein the malpositioned testis finds itself at the wrong temperature after birth, which leads to secondary germ cell loss and later infertility and risk of cancer. Recent studies suggest that neonatal gonocytes transform into the putative spermatogenic stem cells between 3 and 9 months, and this initial postnatal step is deranged in cryptorchid testes. In addition, it is thought the abnormality high temperature may also impair apoptosis of remaining gonocytes, allowing some to persist to become the possible source of carcinoma in situ and malignancy after puberty. The biology of postnatal germ cell development is of intense interest, as it is likely to be the key to the optimal timing for orchidopexy.

No MeSH data available.


Related in: MedlinePlus