Inhibin/activin subunits are immunohistochemically expressed in complete and partial hydatidiform moles.

BACKGROUND AND AIM: Inhibins are dimeric glycoproteins, belonging to the transforming growth factor beta (TGF-beta) family, composed of an alpha-subunit (INH-alpha) and one of two possible beta-subunits (betaA or betaB). Additionally two further beta-subunits (betaC and betaE) have been cloned, although their function remains still quite unclear. The detection by immunohistochemistry of inhibin/activin subunits has been proposed as a useful marker of trophoblastic diseases. Interestingly, a complete mole cannot be easily differentiated from a partial mole. Therefore, the aim of this study was to determine expression changes of the five inhibin/activin subunits in partial and complete moles. MATERIALS AND METHODS: Histologically diagnosed complete (n = 6) and partial (n = 3) hydatidiform moles were immunohistochemical analyzed for INH-alpha, INH-betaA, INH-betaB, INH-betaC and INH-betaE subunits. The immunohistochemical reaction in intermediate trophoblast was analyzed with a semiquantitative score (IRS) and statistical analysis was performed. RESULTS: Immuno-histochemical reaction with INH-alpha, INH-betaA, INH-betaB, INH-betaC and INH-betaE subunits was demonstrated in hydatidiform moles. The INH-betaA and INH-betaB expression was significantly higher in complete compared to partial moles (p < 0.05 each), while INH-alpha, INH-betaC and INH-betaE did not demonstrate any statistically significant differences. CONCLUSION: We demonstrated an immunohistochemical expression of all five inhibin/activin subunits in partial and complete hydatidiform moles. The expression of INH-betaA and INH-betaB determined immunohistochemically was significantly up-regulated in complete moles, suggesting the utilization of these antibodies as diagnostic differentiation markers between complete and partial moles.

Expression of endothelial NO synthase, inducible NO synthase, and estrogen receptors alpha and beta in placental tissue of normal, preeclamptic, and intrauterine growth-restricted pregnancies.

In the physiology of placental blood circulation, nitric oxide (NO) synthases seem to play important roles, although their expression in pathological placentas and their role is still unclear. In addition, NO synthase activation seems to be related to estrogen receptor expression. Therefore, the aims of this study were to investigate the expression of estrogen receptors alpha (ERalpha), estrogen receptor beta (ER and the endothelial NO synthase (eNOS), and inducible NO synthase (iNOS) in intrauterine growth-restricted (IUGR) placentas, preeclamptic placentas, and in normal healthy control placentas. Slides of paraffin-embedded placental tissue were obtained after delivery from patients diagnosed with IUGR, preeclampsia, and normal term placentas and analyzed for eNOS, iNOS as well as ERalpha and ERbeta expression. Intensity of immunohistochemical reaction was analyzed using a semiquantitative score and statistical analysis was performed. In addition, Western blot experiments were performed for comparison of staining intensities obtained by immunohistochemistry and western blot. Expression of eNOS, iNOS, and ERbeta is significantly reduced in trophoblast cells of placentas with IUGR. However, preeclamptic placentas demonstrated a significant elevated expression intensity of these proteins compared with normal controls. A different expression of eNOS, iNOS, ERalpha, and ERbeta by human trophoblast cells seems to results in lower NO output and impaired trophoblast invasion. Results obtained in our study provide evidence that reduced expression of the investigated proteins is related to IUGR.