Involvement of Akt, Ras and cell cycle regulators in the potential development of endometrial hyperplasia in women with polycystic ovarian syndrome.

OBJECTIVE: To examine whether the abundance, localization, and/or activity of cell cycle regulators CDK2, Cyclin E, p27, and survival proteins AKT and Ras in PCOS-associated endometria (with and without hyperplasia) differ from non-PCOS endometria. METHODS: The expression of CDK2, Cyclin E, p27, AKT and Ras was measured by immunohistochemistry and/or Western blot in 9 normal endometria (NE), 12 endometria from PCOS patients without endometrial hyperplasia (PCOSE), 7 endometria from PCOS women with endometrial hyperplasia (HPCOSE), and 9 endometria from patients with endometrial hyperplasia (HE). The activity of CDK2 was assessed by an in vitro kinase assay. RESULTS: CDK2, Cyclin E and p27 proteins were expressed mainly in the endometrial epithelial cells of the studied groups. No change in the activity of CDK2 was observed in total extracts obtained from the tissue samples. However, the nuclear expression of CDK2 in epithelial cells was slightly elevated in PCOSE and significantly increased in HPCOSE when compared to NE. Higher expression of p27 was detected in the cytoplasm of epithelial cells of PCOSE and HPCOSE when compared to NE. Also, we found an increment in Ser473-AKT phosphorylation and an over-expression of the Ras oncogene in endometria of patients with PCOS. CONCLUSION: The PCOS condition is associated with increased Ser473-AKT phosphorylation, elevated expression of Ras, increased cytoplasmic abundance of p27, and increased nuclear abundance of CDK2 in the endometrial epithelial cells. These biological events could potentially provide a chance for endometrial cells from PCOS patients to exit the controlled cell cycle and become hyperplastic at a later stage.

In situ estrogen metabolism in proliferative endometria from untreated women with polycystic ovarian syndrome with and without endometrial hyperplasia.

The aim of the present investigation was to study whether the endocrinological status of women bearing polycystic ovarian syndrome (PCOS) affects the endometrial in situ steroid metabolism. For this purpose, we evaluated the mRNA levels (RT-PCR), and the activity of steroid metabolic enzymes: P450 aromatase, steroid sulfatase (STS), estrogen sulfotransferase (EST) and 17beta-hydroxysteroid dehydrogenase (17beta-HSD) in 23 samples of normal endometria (CE), 18 PCOS endometria without treatment (PCOSE), 10 specimens from PCOS women with endometrial hyperplasia (HPCOSE), and 7 endometria from patients with endometrial hyperplasia not associated to PCOS (EH). The data showed lower levels of STS mRNA for PCOSE and HPCOSE (p<0.05, p<0.01, respectively) and of EST for HPCOSE and EH compared to control (p<0.05). However, higher levels for EST mRNA were obtained in PCOSE (p<0.05) versus CE. The mRNA and protein levels for P450 aromatase were undetectable in all analyzed endometria. The relationship between the activities of STS and EST was lower in PCOSE and HPCOSE (p<0.05) versus CE. The ratio between the mRNA from 17beta-HSD type 1/type 2 was higher in PCOSE (p<0.05), whereas, a diminution in the 17beta-HSD type 2 activity was observed in PCOSE (p<0.05). These results indicate that the activity of enzymes related to the steroid metabolism in analyzed PCOSE differ from those found in the CE. Consequently, PCOSE may present an in situ deregulation of the steroid metabolism.

Levels of Regulatory Proteins Associated With Cell Proliferation in Endometria From Untreated Patients Having Polycystic Ovarian Syndrome With and Without Endometrial Hyperplasia.

Polycystic ovarian syndrome (PCOS) has been associated with endometrial hyperplasia and cancer. The aim of this study was to establish whether the expression of proliferation regulatory proteins in the endometria of patients having PCOS, with or without hyperplasia, differs from control women. Control endometria (CE), patients having PCOS without and with endometrial hyperplasia (PCOSE and HPCOSE, respectively), and that of women with endometrial hyperplasia (HE) were used. The phosphorylated estrogen receptor form (pERα), similar to mother against decapentaplegic (SMAD) 2, SMAD3, and SMAD4, vascular epithelial growth factor (VEGF), and phosphorylated SMAD (pSMAD) 2 and pSMAD3 were detected by immunohistochemistry or Western blot. The results show higher levels of pERα in HE versus CE (P < .05), while higher VEGF levels were found in PCOSE and HE (P < .05) compared to CE; SMAD2 diminished in HE (P < .05) versus CE. Consequently, the higher levels of VEGF and pERα in PCOSE could represent early changes in the progression of PCOSE toward hyperplasia and cancer, whereas changes observed in SMAD proteins support the differential origin of the pathologies of HPCOSE and HE.

Deregulation of tissue homeostasis in endometria from patients with polycystic ovarian syndrome with and without endometrial hyperplasia.

OBJECTIVE: To study the proteins involved in endometrial homeostasis in PCOS women. METHODS: Protein expression of Ki67, Bcl-2, Bax, Pro-Caspase-3 and Caspase-3 by immunohistochemistry and/or Western blot, and DNA fragmentation using in situ 3'-end labeling of apoptotic cells, was measured in 9 samples of normal endometrium (NE), 12 PCOS endometria without treatment (PCOSE), 7 endometria from PCOS women with endometrial hyperplasia (HPCOSE) and 9 endometria from patients with endometrial hyperplasia (HE). RESULTS: Cell proliferation was higher in epithelium from PCOSE (P<0.05), HPCOSE and HE vs NE. A higher Bcl-2/Bax relative ratio in PCOSE and HPCOSE was observed, in absence of active Caspase-3 and scarce DNA fragmentation in the four groups of endometria studied. CONCLUSION: As the apoptosis was scarce in all of the groups studied, endometrial homeostasis deregulation in PCOS could be a result of increased proliferation. Therefore, the onset of endometrial hyperplasia in PCOS endometrium could be linked to inadequate cell proliferation, and concomitantly to inadequate cell survival.

Expression of molecules associated with tissue homeostasis in secretory endometria from untreated women with polycystic ovary syndrome.

BACKGROUND: The hormonal alterations observed in women with polycystic ovary syndrome (PCOS) may promote implantation failure as well as disruption of their endometrial homeostasis. To evaluate cell survival of mid-secretory endometrium from untreated women with PCOS, we measured the expression of apoptosis and proliferation-related proteins. METHODS: A case-control study of 11 patients with PCOS and 11 fertile women in the Hospital Research Unit was performed. Endometrial samples were obtained from PCOS women (PCOSE) and fertile healthy women (CE) during the mid-secretory phase of the menstrual cycle. Protein expressions for Akt, p-AktSer473 and p-AktThr308, Bad, p-BadSer136, Bcl-2, Bax and pro-caspase-3/caspase-3, were assessed by western blot, and Ki67 and p-histone-3 (p-H3) by immunohistochemistry. RESULTS: In CE and PCOSE, a predominance of p-AktThr308 over p-AktSer473 is observed; p-BadSer136 expression is higher in PCOSE than in CE (P < 0.05). Also, Bcl-2 protein is overexpressed in PCOSE (P < 0.05), with no changes in Bax expression among the two groups, resulting in a significantly higher Bcl-2/Bax ratio in PCOSE than in CE (P < 0.05). No changes in the expression of caspase-3 are obtained between both groups of endometria. Furthermore, cell proliferation detected by the expression of Ki67 and p-H3 proteins is higher in the epithelia than the stroma of PCOSE versus CE (P < 0.05). CONCLUSION: The abnormal tissue homeostasis exhibited by the secretory endometrium from PCOS patients with spontaneous ovulation may interfere with their endometrial receptivity.

Androgen and estrogen receptors and co-regulators levels in endometria from patients with polycystic ovarian syndrome with and without endometrial hyperplasia.

OBJECTIVE: To study if the endocrinological status of PCOS women affects the endometrial sensitivity to steroids by evaluating the expression of androgen receptor (AR), estrogen receptor alpha (ERalpha), estrogen receptor beta (ERbeta), co-activators AIB1 and ARA70, and co-repressor NCoR. METHODS: Gene and/or protein expression of steroid receptors and co-regulators was measured in 17 samples of normal endometrium (NE), 23 PCOS endometrium without treatment (PCOSE), 11 endometria from PCOS women and with endometrial hyperplasia (HPCOSE), and 10 endometria from patients with endometrial hyperplasia (HE), using RT-PCR and/or immunohistochemistry and Western blot. RESULTS: Gene and protein expression of AR was relatively elevated in PCOSE and HPCOSE compared with NE. A significant increase in ERalpha protein expression was observed in PCOSE, preferentially in the nucleus of endometrial cells, whereas ERbeta gene and protein expression increased gradually from PCOSE to HPCOSE and HE, mainly in the epithelial compartment. Importantly, we found a gradual increase in the ERbeta/ERalpha gene and protein expression ratio in endometria from the four groups of women. AIB1 showed increased nuclear protein expression in PCOSE compared to NE, in the presence of a high expression of ARA70 in all groups. High expression of ARA70 together with a normal expression level of AIB1 was observed in HPCOSE. The cytoplasmic immunostaining of NCoR was similar between the four groups of patients. CONCLUSION: The PCOS endometrium exhibits a higher sensitivity to steroid action. We can inferred that these alterations could deregulate the transcription of genes involved in the cell cycle, which may lead to the development of endometrial hyperplasia in PCOS women.

Forensic identification of skeletal remains from members of Ernesto Che Guevara's guerrillas in Bolivia based on DNA typing.

We report the positive identification of several members of the guerrillas led by Ernesto "Che" Guevara on the 1960 s in Bolivia by means of DNA fingerprinting. Successful DNA typing of both short tandem repeat loci and the hypervariable region of the human mitochondrial DNA was achieved after extracting total DNA from bones obtained from two burial sites. Given the size of the Cuban database for the STR allele frequencies, a conservative approach was followed to estimate the statistical significance of the genetic evidence. The estimated probabilities of paternity for the two cases in which the paternity logic was applied were higher than 99%. One case was analyzed using mitochondrial DNA and could not be excluded from the identity proposed by the forensic anthropology team. A fourth case was identified by exclusion, on the basis of the positive identification of the other remains, the historical and other anthropological evidence.