Abnormal liver function test in hydatidiform moles: a retrospective study comparing the hyperthyroid state and the euthyroid state

INTRODUCTION

The effect of a hyperthyroid or euthyroid state on liver function tests in patients with hydatidiform moles (HM) is not known. The aim of this study was to determine the effect of hyperthyroidism on liver transaminases in HM.

PATIENTS AND METHODS

We retrospectively reviewed aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in 80 patients with HM (23 complete moles and 57 partial moles).

RESULTS

Of the 80 HM patients, 52 (65%) were euthyroid and 28 (35%) were hyperthyroid. The number of gravida and the levels of serum β-human chorionic gonadotropin (β-HCG), AST, and ALT were significantly higher in the hyperthyroid state than in the euthyroid state (p = 0.033, p = 0.001, p = 0.001 and p = 0.001; respectively). Number of gravida, serum TSH and total T4 were significantly higher in complete HM than partial HM (p < 0.05, p < 0.001, p < 0.05; respectively).

CONCLUSIONS

Our results demonstrated that HM-related β-HCG may activate thyroid cells via TSH-related signalling, resulting in the release of high levels of FT4, FT3, TT3 and TT4, and a subsequent decrease in TSH.

Trophoblastic neoplasms express fatty acid synthase, which may be a therapeutic target via its inhibitor C93

Fatty acid synthase (FASN) is an emerging tumor-associated marker and a promising antitumor therapeutic target. In this study, we analyzed the expression of FASN in normal and molar placentas, as well as gestational trophoblastic neoplasia, and assessed the effects of a new FASN inhibitor, C93, on cellular proliferation and apoptosis in choriocarcinoma cells. Using a FASN-specific monoclonal antibody, we found that FASN immunoreactivity was detected in the cytotrophoblast and intermediate (extravillous) trophoblast of normal and molar placentas, as well as in placental site nodules. All choriocarcinomas (n = 33), 90% of epithelioid trophoblastic tumors (n = 20), and 60% of placental site trophoblastic tumors (n = 10) exhibited FASN positivity. FASN expression was further confirmed in vitro by Western blot and real-time PCR. Treatment of JEG3 and JAR cells with C93 induced significant apoptosis through the caspase-3/caspase-9/poly(ADP)ribose polymerase pathway. Cell cycle progression was not affected by the inhibitor. In summary, the data indicate that FASN is expressed in the majority of gestational trophoblastic neoplasias, and is essential for choriocarcinoma cells to survive and escape from apoptosis. FASN inhibitors such as C93 warrant further investigation as targeted therapeutic agents for metastatic and chemoresistant gestational trophoblastic neoplasia.

Catalase activity, serum trace element and heavy metal concentrations, vitamin A, vitamin D and vitamin E levels in hydatidiform mole

PURPOSE OF INVESTIGATION

In this study we aimed to measure the activity of catalase, which is an antioxidant enzyme, the concentrations of some trace elements and heavy metals, and vitamin A, D and E levels in serum samples of patients with hydatidiform mole, normal pregnancies and healthy non pregnant women.

METHODS

Seventy-two women were enrolled in this study. Of these, 24 were healthy women in the first trimester of pregnancy (HP), 24 were healthy non-pregnant women (NP) and 24 were patients with complete hydatidiform mole (CHM).

RESULTS

Serum levels of catalase, Zn, Co, vitamin A, D and E were significantly lower in the CHM group when compared with the HP and NP groups (p < 0.001). Serum levels of Cu, Fe, and Cd were significantly higher in the CHM group when compared with the HP and NP groups (p < 0.001).

CONCLUSION

The assessment of oxidant/antioxidant imbalance in pregnant women could be useful in the early determination of molar pregnancy and supplementation with antioxidants may be useful in the treatment of CHM, and may prevent recurrent molar pregnancy.

Indoleamine 2,3-dioxygenase expression in gestational trophoblastic disease: implications for development of immunotherapeutic approaches

OBJECTIVE

To examine the immunoexpression of indoleamine 2,3-dioxygenase (IDO) in gestational trophoblastic neoplasia (GTN), including hydatidiform moles and gestational trophoblastic tumors.

STUDY DESIGN

GTN cases were identified from a referral center for trophoblastic disease, and sections were immunostained with anti-IDO antibody and classified as positive or negative for trophoblast staining relative to normal chorionic villi.

RESULTS

Fifty-two cases were included: 10 nonmolar hydropic miscarriages (HA), 11 partial moles (PHM), 9 complete moles (CHM), 15 choriocarcinoma cases (CC) and 7 placental site trophoblastic tumors (PSTT). All HA, PHM and CHM demonstrated IDO staining; 2 of 15 CC were strongly positive, 6 demonstrated focal positivity (< 10% of tumor cells), and the remainder were negative. Of the 7 PSTT, only 2 showed focal weak positivity; the others were negative.

CONCLUSION

Hydatidiform moles express IDO, but the majority of gestational trophoblastic tumors, despite arising from villous or nonvillous trophoblast, do not express this enzyme, suggesting that IDO-mediated immunoregulation is unlikely to be a major component of the malignant phenotype in these tumors. Immunotherapeutic approaches involving IDO might represent ancillary approaches in a minority of patients with GTN.

Assessment of Her-2/neu expression in hydatidiform moles for prediction of subsequent gestational trophoblastic neoplasia

OBJECTIVE

The aim of the present study was to asses the ability of Her-2/neu immunohistochemical staining of the molar tissue to predict the risk of developing gestational trophoblastic neoplasia (GTN).

METHODS

Sections prepared from 33 consecutive formalin-fixed paraffin-embedded archival reconfirmed hydatidiform mole tissue blocks were immunohistochemically stained for Her-2/neu. The staining was scored according to the subjectively evaluated intensity of staining and the proportion of stained villous cytotrophoblastic cells. Clinical data were abstracted from medical files.

RESULTS

23 patients had a complete and 10 a partial mole. Nine patients (27.3%) were diagnosed with GTN [7 of 23 patients with a complete mole (30.4%) and 2 of the 10 (20.0%) with a partial mole]. A positive immunohistochemical Her-2/neu stain was found in 6 (18.2%) of the patients with hydatidiform mole (3 with a complete mole). The rate of Her-2/neu expression was somewhat higher in moles with subsequent GTN than in moles with an uneventful course (22.2% vs. 16.6%, respectively). The difference did not reach significance (Fisher's Exact Test, P=0.55) possibly due to the small number of cases (power of <5%). The sensitivity and specificity of Her-2/neu expression for prediction of GTN was 22.2% and 83.3%, respectively, and the positive and negative predictive value 33.3% and 74.1%, respectively.

CONCLUSION

While the specificity of Her-2/neu immunohistochemical staining for prediction of GTN is relatively high, the low sensitivity and low positive and negative predictive value precludes its practical clinical use for prediction of post-molar GTN. The quest for a precise predictor of post-molar GTN should continue.

Increased adenosine deaminase in hydatidiform mole

BACKGROUND

The aim of the current study was to investigate levels of adenosine deaminase in plasma of patients with hydatidiform mole.

METHODS

Plasma adenosine deaminase levels were determined in 17 women with normal pregnant course, in 17 women with hydatidiform mole, and in 17 non-pregnant healthy volunteers.

RESULTS

Mean adenosine deaminase activity in the hydatidiform mole group was 121.5+/-24.8 U/L, significantly higher than in the pregnant control (7.8+/-6.5 U/L; p<0.0001) and non-pregnant control groups (6.4+/-7.4 U/L; p<0.0001). A cutoff level of 40.5 U/L was found, with both sensitivity and specificity of 100%.

CONCLUSIONS

Adenosine deaminase may play a role in the development of hydatidiform mole.

11beta-Hydroxysteroid dehydrogenase activity in pregnancies complicated by hydatidiform mole

PROBLEM

11beta-Hydroxysteroid dehydrogenase (11beta-HSD) plays an important role in regulating active glucocorticoid reaching the fetus. In normal pregnancy, placental 11beta-HSD functions primarily in oxidative direction. Placental tissue of patients with pregnancies complicated by pre-eclampsia exhibit significantly lower type 1 and 2 11beta-HSD activities and significantly high cortisol level in cord blood suggesting fetal exposure to higher level of active glucocorticoids. The activity of 11beta-HSD in gestational trophoblastic disease has not been determined. The objective of this study was to assess 11beta-HSD activity in tissue from normal second trimester and pregnancies complicated by hydatidiform mole.

METHOD OF STUDY

Normal placental tissues were obtained from patients undergoing termination of pregnancy, and from patients undergoing uterine evacuation for hydatidiform mole. Both nicotinamide adenine dinucleotide (NAD)- and nicotinamide adenine dinucleotide phosphate (NADP)-dependent activities were assayed in central villous tissue. Comparison of groups was performed using Student's t-test. A P-value of 0.05 was considered significant. Data are presented as mean +/- S.D.

RESULTS

Tissue obtained from five patients with pathology-proven hydatidiform mole demonstrated significantly lower 11beta-HSD activities compared with placental tissue obtained from normal pregnancies. The mean NAD-dependent 11beta-HSD activity in normal placentas was 386 +/- 109 pmol/min/g placenta and in hydatidiform mole was 74 +/- 54 pmol/min/g placenta (P < 0.01). The mean NADP-dependent 11beta-HSD activity in normal placentas was 370 +/- 120 pmol/min/g placenta and in trophoblastic disease was 68 +/- 69 pmol/min/g placenta (P < 0.01).

CONCLUSION

Our data indicate significant impairment in the ability of hydatidiform mole tissue to inactivate glucocorticoids.

Caspase activity is downregulated in choriocarcinoma: a cDNA array differential expression study

BACKGROUND

Placental trophoblast can be considered to be pseudomalignant tissue and the pathogenesis of gestational trophoblastic diseases remains to be clarified.

AIMS

To examine the role of caspases 8 and 10, identified by differential expression, on trophoblast tumorigenesis.

METHODS

cDNA array hybridisation was used to compare gene expression profiles in choriocarcinoma cell lines (JAR, JEG, and BeWo) and normal first trimester human placentas, followed by confirmation with quantitative real time polymerase chain reaction and immunohistochemistry. Caspase 10 and its closely related family member caspase 8 were analysed.

RESULTS

Downregulation of caspase 10 in choriocarcinoma was detected by both Atlastrade mark human cDNA expression array and Atlastrade mark human 1.2 array. Caspase 10 mRNA expression was significantly lower in hydatidiform mole (p = 0.035) and chorioarcinoma (p = 0.002) compared with normal placenta. The caspase 8 and 10 proteins were expressed predominantly in the cytotrophoblast and syncytiotrophoblast, respectively, with significantly lower expression in choriocarcinomas than other trophoblastic tissues (p < 0.05). Immunoreactivity for both caspase 8 and 10 correlated with the apoptotic index previously assessed by terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (p = 0.02 and p = 0.04, respectively) and M30 (p < 0.001 and p = 0.003, respectively) approaches.

CONCLUSIONS

These results suggest that the downregulation of capases 8 and 10 might contribute to the pathogenesis of choriocarcinoma.

Telomerase activity and the subunit of telomerase in hydatidiform mole and their relationship with the development of postmolar tumor

OBJECTIVES

To investigate the pattern of telomerase activity and the subunit of telomerase in normal placentae and GTD, and to determine the prognostic significance of telomerase activity and the subunit of telomerase in GTD.

METHODS

Telomerase activity human telomerase (hTERT) and human telomerase (hTR) expression were analyzed in the initial uterine evacuation specimen of 63 hydatidiform moles (HMs), 42 normal human placental tissues, 17 malignant gestational trophoblastic tumors, primary cultures of normal villi and JAR cell lines by use of the polymerase chain reaction-based telomeric repeat amplification protocol (TRAP) assay and reverse transcription-polymerase chain reaction (RT-PCR) methods.

RESULTS

Telomerase activity was 100% in primary cultures of normal villi and JAR cell lines and in less than 60-day early placental villi, while only 9.1% in greater than 60-day placental villi, 27% in HMs and 58% in malignant trophoblastic tumors. High levels of hTR could be found in all groups. hTR expression was detected in all cases of < 60-day placental villi, in 72.7% > 60-day placental villi, in 87.3% in HMs and 100% in malignant trophoblastic tumors. Telomerase activity and hTERT expression had significant differences among the groups. Telomerase activity was associated with serum hCG levels but not related to other clinical risk factors.

CONCLUSIONS

Telomerase activity may be correlated with the development of trophoblastic tumors, and hTERT may be a useful diagnostic marker for detecting the existence of malignant trophoblastic cells.

Heme oxygenases in pregnancy II: HO-2 is downregulated in human pathologic pregnancies

PROBLEM

We previously reported a diminished expression of the heme-degrading enzymes heme oxygenases (HO)-1 and HO-2 in decidua and placenta from mice undergoing Th1-mediated abortion, strongly indicating the protective effect of HO in murine pregnancy maintenance. Here we investigated whether the expression of HO-1 and HO-2 is also reduced at the feto-maternal interface of pathologic human pregnancies.

METHOD OF STUDY

Immunohistochemistry was used to detect HOs expression in placental and decidual first-trimester tissue from patients with: spontaneous abortion (n = 14), choriocarcinoma (n = 14), hydatidiform mole (H-mole) (n = 12), compared with normally progressing pregnancies (n = 15). Further, we investigated early third-trimester decidual and placental tissue from patients with pre-eclampsia (n = 13) compared with fetal growth retardation (n = 14) as age-matched controls.

RESULTS

In first trimester tissue, we observed a significant reduction of HO-2 expression in invasive trophoblast cells, endothelial cells, and syncytiotrophoblasts in samples from patients with spontaneous abortion compared with normal pregnancy. H-mole samples showed a diminished expression of HO-2 in invasive trophoblast cells and endothelial cells in comparison with NP, whereas choriocarcinoma samples showed no significant differences compared with the control. In third trimester tissue, HO-2 was also reduced in syncytiotrophoblasts and invasive trophoblast cells from pre-eclampsia compared with samples from fetal growth retardation. HO-1 expression was diminished in all pathologies investigated; however, the differences did not reach levels of significance.

CONCLUSIONS

Our data indicate that HOs play a crucial role in pregnancy and low expression of HO-2, as observed in pathologic pregnancies, may lead to enhanced levels of free heme at the feto-maternal interface, with subsequent upregulation of adhesion molecules, allowing enhanced inflammatory cells migration to the feto-maternal interface.

Lack of involvement of known DNA methyltransferases in familial hydatidiform mole implies the involvement of other factors in establishment of imprinting in the human female germline

BACKGROUND

Differential methylation of the two alleles is a hallmark of imprinted genes. Correspondingly, loss of DNA methyltransferase function results in aberrant imprinting and abnormal post-fertilization development. In the mouse, mutations of the oocyte-specific isoform of the DNA methyltransferase Dnmt1 (Dnmt1o) and of the methyltransferase-like Dnmt3L gene result in specific failures of imprint establishment or maintenance, at multiple loci. We have previously shown in humans that an analogous inherited failure to establish imprinting at multiple loci in the female germline underlies a rare phenotype of recurrent hydatidiform mole.

RESULTS

We have identified a human homologue of the murine Dnmt1o and assessed its pattern of expression. Human DNMT1o mRNA is detectable in mature oocytes and early fertilized embryos but not in any somatic tissues analysed. The somatic isoform of DNMT1 mRNA, in contrast, is not detectable in human oocytes. In the previously-described family with multi-locus imprinting failure, mutation of DNMT1o and of the other known members of this gene family has been excluded.

CONCLUSIONS

Mutation of the known DNMT genes does not underlie familial hydatidiform mole, at least in the family under study. This suggests that trans-acting factors other than the known methyltransferases are required for imprint establishment in humans, a concept that has indirect support from recent biochemical studies of DNMT3L.

Differential distribution of placental leucine aminopeptidase/oxytocinase and aminopeptidase A in human trophoblasts of normal placenta and complete hydatidiform mole

Placental leucine aminopeptidase (P-LAP)/oxytocinase (OTase) degrades several small peptides such as oxytocin (OT), arginine vasopressin (AVP) and angiotensin III (ANGIII), and aminopeptidase A (AP-A) converts angiotensin II (ANGII) to ANGIII. These proteases play an important role in foetal growth and the maintenance of human homeostasis during pregnancy. In this study, we confirmed the distribution of P-LAP and AP-A proteins and messenger RNAs in human trophoblasts in normal placenta and complete hydatidiform mole by immunohistochemical and in-situ hybridization techniques. Immunoreactivity of P-LAP was mainly noted in the apical membrane of syncytiotrophoblasts, and the expression of messenger RNA (mRNA) for P-LAP was predominantly noted in the cytoplasm of syncytiotrophoblastic cells. However, immunoreactivity of AP-A was mainly noted in the apical membrane of cytotrophoblasts and in the basal zone of the syncytiotrophoblasts, and the expression of mRNA for AP-A was predominantly noted in cytoplasm of cytotrophoblastic cells and a little in cytoplasm of syncytiotrophoblastic cells. Thereby, the two proteases were differentially distributed both in normal placenta and hydatidiform mole throughout the gestational age. These results are useful for the further understanding of not only the pathophysiology of pregnancy, but also the pathogenesis of trophoblastic diseases.

Localization of heparanase in normal and pathological human placenta

Degradation of extracellular matrix (ECM) components is critical for invasion. Heparan sulphate proteoglycans are abundant in the ECM of the placenta and the decidua, hence their degradation may disassemble the matrix and facilitate placentation and trophoblast invasion. This study investigates the expression of heparanase in normal and pathological placentation using RT-PCR, in-situ hybridization and immunohistochemistry analysis to detect heparanase in specific cells of the placenta and at the fetal-maternal interface throughout pregnancy. Heparanase was observed in villous cytotrophoblasts (CT), syncytial trophoblasts (ST) and in intermediate trophoblast cell columns in normal first trimester, molar and ectopic pregnancies. The heparanase protein was preferentially expressed in the endothelium of fetal capillaries, and to a much lesser extent in larger fetal vessels. Extravillous trophoblasts (EVT) invading the decidua and the maternal vessels were also heparanase positive. In the second and third trimesters, villous CT remained heparanase positive whereas ST showed variable heparanase expression. EVT invading the placental implantation site were also positively stained. A similar pattern was observed in samples obtained from pre-eclamptic placentae and from placenta accreta. Our results indicate consistent expression of heparanase in normal and abnormal placenta, in small fetal vessels and in a variety of trophoblast subpopulations with different invasive potentials.

Telomerase activity in gestational trophoblastic disease and placental tissue from early and late human pregnancies

BACKGROUND

The aim of this study was to evaluate telomerase activity in tissue from cases of gestational trophoblastic disease (GTD) and in placental tissue from early and late human pregnancies.

METHODS

We used a telomeric repeat amplification protocol assay to measure telomerase activity in 132 tissue samples from normal early pregnancies, spontaneous abortions, normal late pregnancies, cases of late-pregnancy intrauterine fetal death, and GTD.

RESULTS

Telomerase activity was detected more often in normal early pregnancies and cases of GTD than in spontaneous abortions and normal late pregnancies (P < 0.001). During early gestation, no significant difference in detection rates was found between normal pregnancies and complete hydatidiform mole. As gestational age increased, detection rates for normal pregnancies decreased significantly (P = 0.0001), while for complete hydatidiform mole no significant changes occurred.

CONCLUSIONS

Our findings indicate that placental tissue from normal early pregnancies and neoplastic tissue from GTD possess similar levels of telomerase activity. Decreasing regulation of telomerase activity is present in normal pregnancies but not in complete hydatidiform mole. The fact that telomerase activity decreases in cases of fetal demise, and as pregnancy progresses, also suggests that placental senescence may play a role in the development and ageing of the placenta.

Expression of human telomerase reverse transcriptase, the catalytic subunit of telomerase, is associated with the development of persistent disease in complete hydatidiform moles

OBJECTIVE

This study was undertaken to determine the putative role of telomerase activity and human telomerase reverse transcriptase (hTERT) expression in the development of persistent disease in patients with a diagnosis of complete hydatidiform mole. The ribonucleoprotein telomerase has been shown to have a major role in the process of cellular immortality and carcinogenesis. The reactivation of this enzyme that occurs in the development of malignancies appears to be limited by the regulation of its catalytic subunit hTERT. Compared with their somatic counterparts, most human malignancies demonstrate telomerase activity, and this activity is dependent on the cellular presence of hTERT. The role of telomerase in the pathogenesis of complete hydatidiform moles is not clearly understood. Moreover, the role of hTERT in trophoblastic disease, as well as in the development of persistent trophoblastic disease, has yet to be elucidated.

STUDY DESIGN

Telomerase activity and hTERT expression were analyzed in the initial uterine evacuation specimen of 54 complete hydatidiform moles by use of the telomeric repeat amplification protocol assay and reverse transcription-polymerase chain reaction methods. The results were compared and then correlated with the development of persistent trophoblastic disease.

RESULTS

Among the 54 patients who were examined with a diagnosis of complete hydatidiform mole, persistent trophoblastic disease requiring postevacuation chemotherapy developed in 6. In the remaining 48 patients, spontaneous remission of the disease occurred after uterine evacuation. Both telomerase activity and hTERT expression were detected in all 6 cases of persistent disease on the initial molar tissue sampled. Among the 48 nonpersistent moles, telomerase activity was detected in 29 (60%) and hTERT expression was demonstrated in 26 (54%). The detection of hTERT expression was significantly associated with the presence of persistent disease (P =.035). Moreover, the absence of hTERT expression in molar tissue obtained from uterine evacuation demonstrated a 100% negative predictability in determining cases of complete mole that were nonpersistent.

CONCLUSIONS

Compared with telomerase activity, the expression of hTERT is significantly associated with the development of persistent disease in complete hydatidiform moles. The absence of hTERT expression in the initial tissue sample from complete moles may have potential clinical value in determining patients who will eventually undergo spontaneous remission after uterine evacuation.

Telomerase activity in gestational trophoblastic disease

AIMS

To investigate the pattern of telomerase activity in hydatidiform mole as compared with normal placenta and choriocarcinoma, and to determine the prognostic significance of telomerase activity in hydatidiform mole.

METHODS

Telomerase activity in 35 cases of hydatidiform mole, 35 normal placentas, one choriocarcinoma sample, and two choriocarcinoma cell lines (JAR, JEG3) was determined using the sensitive polymerase chain reaction based telomeric repeat amplification protocol (TRAP) assay. Two cases of breast carcinoma and two cases of ovarian carcinoma were also included as positive controls in the telomerase assay.

RESULTS

Telomerase activity was detected in 11 of 30 early placentas (36.7%), one of five term placentas (20%), five of 27 hydatidiform moles which regressed spontaneously (18.5%), and six of eight hydatidiform moles which developed persistent trophoblastic disease (75%) (including three which developed metastases). Hydatidiform moles which subsequently developed persistent disease, especially those which metastasised, were more likely to express telomerase activity (p < 0.01). However, there was no significant difference in the frequency of telomerase activity between early placentas and hydatidiform mole. Strong telomerase activity was observed in choriocarcinoma tissue, choriocarcinoma cell lines, and ovarian and breast carcinomas.

CONCLUSIONS

Telomerase activation occurs in hydatidiform mole with a similar incidence to early normal placentas. This supports the concept that hydatidiform mole is essentially an abnormal conceptus. There is an association between telomerase activation and the development of persistent trophoblastic disease. Further study is warrant to confirm the prognostic significance of telomerase activity in hydatidiform mole.

Expression of telomerase subunits and localization of telomerase activation in hydatidiform mole

Activation of telomerase compensating for the loss of telomeres has been implicated in human cell immortalization and carcinogenesis. Telomeric repeat amplification protocol (TRAP) assay can be used to detect telomerase activity in a variety of malignant tumours, including those of the female reproductive tract which have been found to have high levels of telomerase activity. However, it is unclear whether all the cells or only a subset of cells within a tumour have telomerase activity. To determine the regulation mechanism of telomerase activity in hydatidiform moles, we studied telomerase activity at the single cell level (using an in situ TRAP assay), and expression of TLP1 (telomerase protein 1), TERC (telomerase RNA component) and TERT (telomerase reverse transcriptase component). Expression of TERC and TLP1 was observed in all normal chorionic villi, as well as in trophoblastic diseases, and various cell lines irrespective of telomerase activity. TERT expression was observed in trophoblastic diseases and normal chorionic villi with telomerase activity but not in normal chorionic villi without telomerase activity, except in some cases in the present series, indicating that TERT expression is closely associated with telomerase activity. Upregulation of TERT expression may thus play an important role in telomerase reactivation.

Telomerase activity in complete hydatidiform mole

OBJECTIVE

The purpose of this study was to evaluate the association of telomerase activity in complete hydatidiform moles with subsequent development of persistent gestational trophoblastic tumor.

STUDY DESIGN

By means of the standard telomerase repeat assay, we examined telomerase activity in 4 normal placentas, 31 complete hydatidiform moles (16 cases of uneventful regression, according to serum levels of beta-human chorionic gonadotropin, after evacuation and 15 cases in which persistent gestational trophoblastic disease developed after evacuation), 7 invasive moles, and 5 choriocarcinoma tissue samples.

RESULTS

Telomerase activity was detected in 13 of 15 (86.7%) complete hydatidiform moles in patients who eventually underwent chemotherapy for the treatment of persistent gestational trophoblastic tumors. All 9 patients with metastatic disease (International Federation of Gynecology and Obstetrics stage III) had telomerase activity in the initial molar tissue sample. In contrast, telomerase activity was evident in only 3 of 16 (12.5%) complete hydatidiform moles from patients with spontaneous remission after evacuation (P <.05). Telomerase activity was detected in all 7 invasive moles and all 5 choriocarcinoma tissue samples but was not detected in normal placentas.

CONCLUSION

The presence of telomerase activity in complete hydatidiform moles is associated with the development of persistent gestational trophoblastic tumors, such as invasive moles and choriocarcinoma.

Endothelial nitric oxide synthase immunoreactivity in early gestation and in trophoblastic disease

AIMS

To study the localisation of the endothelial nitric oxide synthase (eNOS) in the normal placenta, with special emphasis on the implantation site in the first trimester of pregnancy, and in the different subtypes of trophoblastic cells in gestational trophoblastic disease.

METHODS

The immunoperoxidase technique with an antibody directed against eNOS was applied to paraffin sections from first and second trimester placentas, placenta accreta, partial and complete hydatidiform moles, and choriocarcinoma. Immunoperoxidase staining for human placental lactogen (hPL) was performed on parallel sections.

RESULTS

Prominent immunoreactivity for eNOS was found to be present in the intermediate trophoblastic cells of the cell columns of the anchoring villi and in trophoblastic cells at the implantation site. Staining was also present in the syncytiotrophoblast, most conspicuous at the apical cell border. In trophoblastic disease, proliferating large mononuclear cells, which were strongly positive for hPL, were found to be immunoreactive for eNOS.

CONCLUSIONS

eNOS immunoreactivity is strongly positive in the extravillous trophoblastic cells and to a lesser extent in the syncytiotrophoblast. In the former it may play a role in implantation and vascular invasion. Cells with differentiation to intermediate trophoblast in complete hydatidiform mole and choriocarcinoma also show high levels of eNOS, which may be associated with the haematogenous mode of spread of trophoblastic disease.

Comparison of telomerase activity in normal chorionic villi to trophoblastic diseases

Trophoblasts are derived from the normal placenta, and they infiltrate into the endometrium and the maternal blood vessels under strict control but, unlike malignant cells, never metastasize. To understand the proliferative characteristics of trophoblasts and its related disorders, we assessed telomerase activity in chorionic villi obtained from 27 normal individuals, 9 hydatidiform moles, and 2 choriocarcinomas. Telomerase activity was detected in 13/27 (48%) normal chorionic villi samples. The detectability and the level of telomerase activity depended on gestational age; 8/10 (80%) villi samples in the first trimester (relative telomerase activity; 1.77 +/- 1.37), whereas 2/8 (25%) villi samples in the second trimester (0.78 +/- 1.52) and 3/9 (33%) in the third trimester (0.28 +/- 0.43) had telomerase activity. Telomerase activity of normal chorionic villi in the first trimester was higher than that of the third trimester (P = 0.0251). In contrast, all mole samples had increased telomerase activity compared to normal villi (3.17 +/- 2.81, P = 0.0152). Thus, a relationship may exist among cell proliferation, telomerase activity, and progression to trophoblastic disease.

Quantitative evaluation of human placental aromatase in abnormal pregnancy--anencephalus and hydatidiform mole

To determine why estriol (E3) levels in the urine and serum are extremely low in pregnancies with anencephalus or hydatidiform mole, both the aromatase activity and the tissue P450arom concentration in solubilized fractions of placental or mole microsomes was measured. The aromatase activity was measured by tritiated water assay and the tissue P450arom concentration was determined by sandwich enzyme-linked immunosorbent assay (ELISA). Consequently, any tissue P450arom concentration was at a lower level than the regression line for that in normal placenta. The aromatase activity also showed a tendency to be lower than that in normal placenta. These results therefore suggest that a decrease of E3 in these abnormal pregnancies would result mainly in a lower level of tissue P450arom concentration.

Developmental regulation of tissue transglutaminase during human placentation and expression in neoplastic trophoblast

The expression of tissue transglutaminase (tTG) was studied during the formation of the normal human placenta and in molar pregnancies and choriocarcinoma, in order to correlate its expression with the functional characteristics of the recognized trophoblast cell types. tTG expression was found to be developmentally regulated. Before 6-7 weeks' gestation, only the chorionic villous cytotrophoblast expresses tTG. Thereafter the overlying syncytiotrophoblast becomes positive. tTG expression is gradually downregulated in the intermediate trophoblast cells emerging from the tips of the chorionic villi invading the uterine tissue. In the decidual wall, the intermediate trophoblast does not express tTG, whereas scattered syncytial cells, the placental bed giant cells, express tTG. Villi from complete hydatidiform mole (CHM) show tTG expression in both the cyto- and the syncytiotrophoblast. The intermediate trophoblast cells from CHM show heterogeneous tTG expression, with a majority of negative cells, whereas extravillous syncytia always express tTG. In choriocarcinoma, the tumour cells show heterogeneous tTG expression, with a majority of positive cells. Analysis of tTG protein and mRNA in placental extracts by Western and Northern blotting did not provide evidence for expression of the truncated form of tTG found in some cell types. The regulated expression of tTG in the normal placenta suggests that the enzyme is involved in important trophoblastic functions and may participate in the control of invasion.

Low aromatase activity in microsomes from complete hydatidiform mole

The complete hydatidiform mole (CHM) is characterized by the presence of aberrant placenta, with hyperplasia of cyto- and syncytiotrophoblasts and the absence of maternal genetic information. Steroidogenesis in this condition is, thus, of special interest. In this study we investigated the kinetic parameters of aromatase in microsomes from CHM compared with those in normal early placenta (NEP). The enzyme activity was determined by measuring the conversion of [3H] testosterone to [3H]estradiol plus [3H]estrone. The Km value for testosterone was 33 nmol/L in CHM and 17 nmol/L in NEP of similar gestational ages. Aminoglutethimide, a nonsteroidal inhibitor, decreased in a dose-dependent manner and with the same potency the aromatization of testosterone in both tissues (ID50, 2 vs. 1 mumol/L in CHM and NEP, respectively). These results suggest that the enzymes from the two sources are kinetically similar. However, the enzyme efficiency, expressed as the maximum velocity/Km ratio, was 17-fold lower in CHM than in NEP tissue (1.22/33 vs. 10.68/17 min/mg.mL). These findings suggest that in molar pregnancy the decreased capacity of trophoblast tissue for the formation of estrogen could increase the testosterone concentration inside the molar vesicle, which, in turn, as we previously reported, inhibits progesterone formation. All of these data could provide an explanation for the low circulating level of progesterone, which may directly or indirectly affect the spontaneous expulsion of this aberrant tissue in the second trimester of pregnancy.

Expression of trophoblast-leukocyte common antigens and placental-type alkaline phosphatase in complete molar pregnancy

The current study was undertaken to determine the localization of trophoblast-leukocyte common antigens and placental-type alkaline phosphatase in complete molar pregnancy with the use of rabbit antiserum and murine monoclonal antibodies in immunofluorescence assays. Trophoblast-leukocyte common antigens were expressed on all normal villous trophoblast (8 to 38 weeks' gestation) and on all complete moles studied. Placental-type alkaline phosphatase was not expressed on villous trophoblast before 20 weeks' gestation in either normal placentas or complete moles. In contrast, there was strong expression of placental-type alkaline phosphatase on villous trophoblast of normal placentas of more than 20 weeks' gestational age. The expression of polymorphic antigens such as trophoblast-leukocyte common antigens and placental-type alkaline phosphatase on molar trophoblast may be important in the immunobiologic features of gestational trophoblastic disease.

Genetic studies on hydatidiform moles. II. The origin of complete moles

An investigation of 50 histologically complete hydatidiform moles was made by examining the molar tissue after termination of pregnancy. Attempts were made to study chromosomes and 11 polymorphic enzymes in the moles and in the blood of the patient and her spouse, although not all studies were possible on every case. Useful information about the origin of the mole was obtained in 28 cases. In no case was there evidence of a maternal contribution and in 14 cases a maternal contribution was definitely excluded. In 27 cases, including the 5 tested who have subsequently required treatment, the mole was homozygous for all genetic markers examined. There were 32 examples, arising in 21 moles, of loci homozygous in the mole where the male parent was known to be heterozygous. There was a single example of a mole heterozygous at one proximal locus (PGM3). The findings are in favour of the doubling of a haploid genome as the most likely origin of the vast majority of complete moles.

Nicotinamide adenine dinucleotide-dependent 15-hydroxyprostaglandin dehydrogenase activity in hydatidiform mole tissue and choriocarcinoma cells

Prostaglandins may occupy an important role in viral and chemical carcinogen-induced neoplasia. To evaluate the possible role of prostaglandin catabolism in neoplastic cells, we measured nicotinamide adenine dinucleotide-dependent 15-hydroxyprostaglandin dehydrogenase activity in hydatidiform mole tissue and in choriocarcinoma cells maintained in monolayer culture. The specific activity of nicotinamide adenine dinucleotide-dependent 15-hydroxyprostaglandin dehydrogenase in hydatidiform mole tissue (0 to 1.2 nmol 15-ketoprostaglandin E2 formed x min-1 x mg-1 cytosolic protein) and in choriocarcinoma cells (1.0 nmol 15-ketoprostaglandin E2 x min-1 x mg-1 protein) was strikingly less than that found in normal placental tissue [11.4 +/- 2.3 (S.E.) nmol 15-ketoprostaglandin x min-1 x mg-1 protein].

Studies of beta-glucuronidase in first-trimester placenta, term placenta and hydatidiform mole

The specific activity and isoenzyme pattern of beta-glucuronidase (beta-D-glucuronide glucurononosohydrolase, EC 3.2.1.31) from first-trimester placenta, term placenta and hydatidiform mole were compared. Enzyme activity is highest in term placenta and lowest in hydatidiform mole, reflecting the steroid conjugation requirements of the tissues. The difference in enzyme activity is due to variation in the level of one isoenzyme form (isoenzyme B) of beta-glucuronidase, which is absent in molar tissue. The possible cause for the changing isoenzyme pattern is discussed.

N-Acetyl-beta-glucosaminidase activity in hydatidiform mole

The N-acetyl-beta-glucosaminidase activity in hydatidiform mole is two-fold higher than that in full-term placenta. Qualitatively, the enzymes from the two tissues are similar with respect to KM values and pH optima. Both enzymes also contain a new isoenzyme form detectable by polyacrylamide gel electrophoresis. However, the molar enzyme is more susceptible to heat denaturation, presumably due to the presence of a higher level of the heat-labile isoenzyme form A in this tissue. Data are also presented incicating that the placenta is not the source of the N-acetyl-beta-glucosaminidase activity in maternal serum.