Sertoli cell dedifferentiation in human cryptorchidism and gender reassignment shows similarities between fetal environmental and adult medical treatment estrogen and antiandrogen exposure.

Studies over the last years show an increase in testicular cancer, hypospadias and cryptorchidism in industrial countries, leading to the concept of testicular dysgenesis syndrome (TDS). It is hypothesized that TDS is caused by estrogen and antiandrogen exposure during fetal life, accompanied by incomplete maturation of testicular Sertoli cells (SC). However, it is not known if SC disruption is a primary cause or a response to fetal Leydig cell testosterone production changes. To determine if SC differentiation is directly affected by estrogens, we compared SC maturation between adult gender reassignment cases exposed to estrogen and antiandrogen therapy, and those of typical TDS in adult cryptorchidism. We found similar expression of immature SC markers M2A antigen, inhibin bodies and Anti Mullerian Hormone, and the absence of maturation marker androgen receptor in SC of both types of patients. These data supports the occurrence of true SC dedifferentiation caused by estrogen exposure in adult humans. Our data also suggests that SC maturation is directly disrupted in TDS.