The stage of cellular differentiation at the time of DES exposure may be critical in the final expression of these abnormalities
The association of intrauterine exposure to diethylstilbestrol (DES) and the subsequent development of reproductive tract abnormalities in young women has been well documented. Although the incidence of vaginal adenocarcinoma was low in the exposed population, vaginal adenosis, a nonmalignant abnormality, was quite common. In order to study the pathogenesis of adenocarcinoma and to determine the frequency of adenosis following prenatal exposure to DES, timed pregnant CD-1 mice were treated s.c. with DES (dose range, 5 to 100 micrograms/kg/day) on Days 9 though 16 of gestation. This period corresponds to major organogenesis of the reproductive tract in the mouse. Female offspring were sacrificed between 1 and 18 months of age. In addition to nonmalignant abnormalities, some of which have been described in women exposed prenatally to DES, two cases of vaginal adenocarcinoma (2%) were observed in 91 prenatally DES-treated animals. No comparable epithelial lesions were seen in 158 control female mice. One other case of adenocarcinoma of the vagina was reported previously by this laboratory using the prenatally exposed animal model. In another series of mice treated prenatally with DES, 100 micrograms/kg/day, 3 of 20 (15%) 1-month-old animals and one of 10 (10%) 18-month-old treated offspring had glandular epithelium abnormally located in the vaginal fornices (adenosis). Other cervicovaginal abnormalities observed after prenatal DES exposure included structural alterations, cervical enlargement, squamous metaplasia in the endocervical canal, excess keratinization of the ectocervix and vagina, transverse folds and basal cell hyperplasia in the upper vagina, and prominent Wolffian duct remnants. Thus, vaginal adenosis in the mouse does not appear to be a common abnormality following treatment with DES in utero. Neonatal exposure to DES on Days 1 to 5, on the other hand, resulted in six of eight (75%) animals with adenosis at 35 days of age. Since perinatal mouse studies have reported high incidences of vaginal adenosis, but, to our knowledge, no cases of vaginal adenocarcinoma, the results presented in this report suggest that the stage of cellular differentiation at the time of DES exposure may be critical in the final expression of these abnormalities.
Women pre-natally exposed to DES develop abnormalities that can lead to cancer
Exposure to exogenous hormones during development can result in permanent health problems. In utero exposure to diethylstilbestrol (DES) is probably the most well documented case in human history. DES, an orally active synthetic estrogen, was believed to prevent adverse pregnancy outcome and thus was routinely given to selected pregnant women from the 1940s to the 1960s. It has been estimated that 5 million pregnant women worldwide were prescribed with DES during this period. In the early 1970s, vaginal clear cell adenocarcinomas (CCACs) were diagnosed in daughters whose mother took DES during pregnancy (known as DES daughters). Follow up studies demonstrated that exposure to DES in utero causes a spectrum of congenital anomalies in female reproductive tracts and CCACs. Among those, cervical and vaginal adenosis are most commonly found, which are believed to be the precursors of CCACs. Transformation related protein 63 (TRP63/p63) marks the cell fate decision of Müllerian duct epithelium (MDE) to become squamous epithelium in the cervix and vagina. DES disrupts the TRP63 expression in mice and induces adenosis lesions in the cervix and vagina. This review describes mouse models can be used to study the development of DES-induced anomalies, focusing on cervicovaginal adenoses, and discusses its molecular pathogenesis.
NCBI, PMC3443265, Oct 2012 The Development of Cervical and Vaginal Adenosis as a Result of Diethylstilbestrol Exposure In Utero.
Women exposed to DES in utero develop abnormalities, including cervicovaginal adenosis that can lead to cancer
Women exposed to diethylstilbestrol (DES) in utero develop abnormalities, including cervicovaginal adenosis that can lead to cancer. We report that transient disruption of developmental signals by DES permanently changes expression of p63, thereby altering the developmental fate of Müllerian duct epithelium. The cell fate of Müllerian epithelium to be columnar (uterine) or squamous (cervicovaginal) is determined by mesenchymal induction during the perinatal period. Cervicovaginal mesenchyme induced p63 in Müllerian duct epithelium and subsequent squamous differentiation. In p63(-/-) mice, cervicovaginal epithelium differentiated into uterine epithelium. Thus, p63 is an identity switch for Müllerian duct epithelium to be cervicovaginal versus uterine. P63 was also essential for uterine squamous metaplasia induced by DES-exposure. DES-exposure from postnatal day 1 to 5 inhibited induction of p63 in cervicovaginal epithelium via epithelial ERalpha. The inhibitory effect of DES was transient, and most cervicovaginal epithelial cells recovered expression of p63 by 2 days after discontinuation of DES-treatment. However, some cervicovaginal epithelial cells failed to express p63, remained columnar and persisted into adulthood as adenosis.
NCBI, PMID: 14998922, Apr 2004 – Full article The Company of Biologists Limited131/7/1639 15 Dec 2003.