Use of proliferation cell nuclear antigen immunoreactivity for distinguishing hydropic abortions from partial hydatidiform moles

Macrophage Polarization in Placenta Accreta and Macrophage-trophoblast Interactions

PROBLEM

Placenta accreta (PA) is defined by an abnormal invasion of placental trophoblasts into the myometrium, which can lead to serious postpartum complications. Macrophages play an important role in the regulation of trophoblast function. Both granulocyte colony-stimulating factor (G-CSF) and its receptor (granulocyte colony-stimulating factor receptor, G-CSFR) have effects on trophoblast invasion. However, the current understanding of G-CSF secretion, G-CSFR expression, abnormal polarization of decidual macrophages (dMϕ) in PA and the abnormal invasion of placental trophoblasts into the myometrium are limited.

METHOD OF STUDY

The polarization of dMϕ in PA was analyzed by flow cytometry (FCM), and the expression of G-CSFR in placental trophoblasts in PA was evaluated by immunohistochemistry. In an in vitro co-culture model, we investigated the effects of HTR-8/SVneo trophoblasts cell line (HTR-8) on macrophage human monocyte cell line (THP-1) polarization and G-CSF secretion, and we also analyzed the effects of THP-1 cells, especially M2-like subtype, on primary trophoblasts and HTR-8 proliferation, invasion, and adhesion. FCM, transwell assays, adhesion assays, and proliferation assays were used in the above model.

RESULTS

Compared with controls (n = 9), dMϕ showed significantly lower levels of M1 markers CD80 and CD86 and higher levels of the M2 markers CD163 and CD206, and G-CSFR expression of placental trophoblasts was increased in PA(n = 5). In vitro experiments showed that the trophoblast HTR-8 cell line induced polarization of THP-1 cells to an M2-like subtype and increased their secretion of G-CSF. Furthermore, IL-4/IL-13-induced M2-like THP-1 macrophages were able to increase the expression of G-CSFR, proliferation, invasion and adhesion of both primary trophoblasts and HTR-8 trophoblasts.

CONCLUSIONS

There is an altered immune imbalance at the maternal-fetal interface in PA, which further may lead to abnormal trophoblast function. G-CSF and its receptors may play important roles in abnormal polarization of macrophages and abnormal invasion of trophoblasts. This article is protected by copyright. All rights reserved.

Proliferation of trophoblasts and Ki67 expression in preeclampsia

BACKGROUND/AIMS

Preeclampsia is a pregnancy-specific disease with the increased risk of maternal morbidity and mortality. It is characterised by placental vascular dysfunction. Despite the numerous studies on preeclampsia, studies evaluating proliferation of villous trophoblasts in preeclamptic placentas are limited. Ki67 is a proliferation marker that expresses in the nuclei of proliferating cells. In this study, we examined the proliferation of villous trophoblasts in placentas of preeclamptic patients by using Ki67 and compared it with placentas of normal pregnant patients.

MATERIAL AND METHODS

The current study is a prospective one, including 15 placentas from preeclamptic patients and 14 placentas from normal pregnancies as controls. For detection of proliferation in villous trophoblasts, Ki67 was used.

RESULTS

The Ki67 index was 11.48±1.67% in normal patients and 15.53±2.28% in preeclamptic patients. There was a difference in Ki67 index between the two groups (p < 0.001).

CONCLUSION

Our results support the opinion that trophoblasts undergo regeneration hyperplasia as a result of injuries arising on the villous surface in preeclampsia. Proliferation of trophoblasts may contribute the development of preeclampsia.

Histopathological diagnosis of hydatidiform mole: contemporary features and clinical implications

Gestational trophoblastic neoplasia (GTN) encompasses several entities including complete (CHM) and partial (PHM) hydatidiform mole (HM), malignant choriocarcinoma, and placental-site trophoblastic tumor. HMs are genetically abnormal, nonviable conceptions, which are associated with significantly increased risk for development of complications due to persistence of abnormal trophoblast (persistent GTN; pGTN), which occurs following 15% of CHM and 0.5% of PHM. Diagnostic histological features of HM are present in the first trimester but these features differ from those traditionally described in the later second trimester. The characteristic morphological findings of early HM include aspects of villous dysmorphism and abnormal villous trophoblast hyperplasia, with other specific features allowing reliable distinction between CHM and PHM. Optimal management of molar disease depends on its early histological identification and subsequent surveillance by measurement of maternal human chorionic gonoadotropin (hCG) for detection of pGTN based on rising or plateuing hCG levels such that early effective treatment is possible.

Immunohistochemical and functional biomarkers of value in female genital tract lesions

There has been a marked expansion in the literature pertaining to the use of immunohistochemical markers in female genital tract pathology, especially with regard to diagnosis. This review provides a survey of the antibodies commonly used in the diagnosis of gynecological lesions grouped as to function or type. Prognostic or predictive markers are also discussed where appropriate, although few of these are of value in everyday practice. It is stressed that when immunohistochemistry is used diagnostically, panels of markers provide better information than reliance on a single antibody.

Minichromosome maintenance protein 7 expression in gestational trophoblastic disease: correlation with Ki67, PCNA and clinicopathological parameters

AIMS

To assess the proliferative activity of gestational trophoblastic disease (GTD) using one of the novel proliferation markers (MCM7) and to determine its prognostic value in hydatidiform mole (HM).

METHODS AND RESULTS

Immunohistochemical staining for MCM7 was performed on 122 samples of paraffin-embedded trophoblastic tissues including 22 normal first-trimester placentas, 12 term placentas, 12 spontaneous miscarriages (SM), 21 partial moles (PM), 44 complete hydatidiform moles (CM), and 11 choriocarcinomas (CCA). The correlations between the proliferative indices assessed by MCM7, proliferating cell nuclear antigen (PCNA) and Ki67 (MIB1) immunoreactivity as well as clinical progress were assessed. MCM7 immunoreactivity was found predominantly in the nuclei of cytotrophoblast and intermediate trophoblast and decreased with placental maturation. MCM7 expression was highest in CCA, followed by CM, PM, normal first-trimester placenta, SM and term placenta. MCM7 index was significantly higher in PM and CM than in SM (P = 0.007, P < 0.001) but not between PM and CM themselves (P = 0.560). Eighteen of the 65 patients with HM developed persistent trophoblastic disease (PTD) requiring chemotherapy. There was no significant difference in MCM7 indices between the patients who developed PTD and those who did not (P = 0.312). MCM7 indices correlated well with Ki67 (P = 0.002) but not with PCNA (P = 0.054) indices. MCM7 indices demonstrated less variability than PCNA and Ki67 and may be a better proliferation marker than the latter two.

CONCLUSIONS

We conclude that MCM7 is useful in differentiating molar and non-molar gestations but is not helpful in discriminating PM from CM or in predicting PTD.

Histopathological diagnosis of partial and complete hydatidiform mole in the first trimester of pregnancy

The diagnosis of molar pregnancy is a continuing diagnostic problem for many practicing histopathologists who are required to examine specimens of products of conception, particularly since changes in gynecological management in recent years have resulted in uterine evacuation at earlier gestations. The aim of this review is to provide practical, up-to-date, diagnostically useful information regarding the histological diagnosis of molar disease in early pregnancy. Pathophysiological issues relevant to molar pregnancies, such as genetic abnormalities, will be briefly summarized, but nonhistopathological aspects of molar disease will not be covered in detail in this review.

Expressions of proliferation markers (Ki-67, proliferating cell nuclear antigen, and silver-staining nucleolar organizer regions) and of p53 tumor protein in gestational trophoblastic disease

OBJECTIVE

This study was undertaken to determine whether the expressions of 3 proliferation markers (Ki-67, proliferating cell nuclear antigen, and silver-staining nucleolar organizer regions) and of p53 tumor protein could differentiate spontaneous abortions from gestational trophoblastic diseases and also discriminate among gestational trophoblastic disease subgroups.

STUDY DESIGN

Twenty-two partial hydatidiform moles, 17 complete hydatidiform moles, 6 invasive hydatidiform moles, and 20 nonhydropic spontaneous abortions (control group) were evaluated by means of immunohistochemical techniques with antibodies to Ki-67, proliferating cell nuclear antigen, and p53. One-step silver staining was used to detect silver-staining nucleolar organizer regions.

RESULTS

The expressions of Ki-67, proliferating cell nuclear antigen, silver-staining nucleolar organizer regions, and p53 were significantly higher in the gestational trophoblastic disease group than in the control group. The results of linear discriminant analysis showed that silver-staining nucleolar organizer region count had the highest sensitivity and specificity (93.3% and 100%, respectively) for distinguishing gestational trophoblastic disease from spontaneous abortion. Sensitivity and specificity for discriminating gestational trophoblastic disease from spontaneous abortion increased to 100% when all four markers were used together. Proliferating cell nuclear antigen was found to be the best discriminating variable for differentiating among gestational trophoblastic disease subgroups.

CONCLUSION

Our findings suggest that expressions of Ki-67, proliferating cell nuclear antigen, silver-staining nucleolar organizer regions, and p53 may aid in the diagnosis of gestational trophoblastic diseases. These fairly rapid, simple, and economic techniques could serve as a useful adjunct to conventional methods in the diagnosis of gestational trophoblastic diseases.

Comparison of villous trophoblast proliferation rate in hydatidiform mole and non-molar abortion by assessment of proliferating cell nuclear antigen expression

This study examines the proliferative activity of trophoblast in hydatidiform mole, non-molar hydropic abortion and non-molar spontaneous abortion. Nine cases of complete mole, 10 cases of partial mole, eight cases of non-molar hydropic abortion and six cases of non-hydropic second trimester abortion were examined by routine histopathology and the rate of cell proliferation was assessed by immunoreactivity for proliferating cell nuclear antigen (PCNA). Hydropic abortion showed a significantly lower PCNA index than complete mole and partial mole. There was no significant difference in PCNA index between partial mole and non-hydropic abortion. The trophoblast of partial hydatidiform mole demonstrates significant cell proliferation but this, although higher than that of hydropic abortion, is no higher than that of non-hydropic abortion of a similar gestational age. The role of partial mole as a precursor of persistent gestational trophoblastis disease remains unclear.

Assessment of cell proliferation in hydatidiform mole using monoclonal antibody MIB1 to Ki-67 antigen

AIMS

To assess the role of Ki67 immunoreactivity in predicting the clinical progress of hydatidiform mole.

METHODS

Tissue from 87 hydatidiform moles, 11 normal first trimester placentas, 11 normal term placentas and 17 spontaneous abortions were examined for expression of Ki67 antigen, using the monoclonal antibody MIB1.

RESULTS

Ki67 immunoreactivity was significantly higher in the tissue from normal first trimester placentas than in that from normal term placentas and spontaneous abortions. Among the 87 patients with hydatidiform moles studied, 20 developed persistent gestational trophoblastic disease and required subsequent treatment. There was no statistically significant difference in the Ki67 index between the 20 patients who developed persistent disease and those who did not.

CONCLUSION

Hydatidiform moles which give rise to persistent trophoblastic disease do not have a higher proliferative rate than those which do not. The Ki67 index is not useful for predicting the prognosis of molar pregnancies.

Can histopathologists reliably diagnose molar pregnancy?

AIMS

To assess the degree of difficulty in diagnosing partial mole by analysing intraobserver and interobserver agreement among a group of pathologists for these diagnoses.

METHODS

Fifty mixed cases of partial mole, complete mole, and non-molar pregnancy were submitted to seven histopathologists, two of whom are expert gynaecological pathologists; the other five were district general hospital consultants, one of whom works in Australia. These participants gave each slide a firm diagnosis of either partial mole, complete mole, or non-molar pregnancy. Some 12 months later, the slides were recorded and again submitted for a second diagnostic round to assess intraobserver as well as interobserver agreement. Standard histological criteria for each diagnostic category were circulated with the slides.

RESULTS

kappa statistics showed that complete mole could be reliably distinguished from non-molar pregnancy, but neither non-molar pregnancy nor complete mole could be easily differentiated from partial mole. In only 35 out of 50 cases was there agreement between five or more of the seven participants. Agreement between the expert gynaecological pathologists was no better than for others in the group. Interestingly, the intraobserver agreement for each pathologist was good to excellent.

CONCLUSIONS

These results imply that the reported histological criteria are either not being applied consistently or that they are lacking in practical use. An atypical growth pattern of trophoblast, rather than the polar accentuation seen in normal first trimester pregnancies, seems to be the important diagnostic histological feature for partial mole. Ploidy studies might also help with problem cases.