Apoptotic activity in gestational trophoblastic disease correlates with clinical outcome: assessment by the caspase-related M30 CytoDeath antibody

Significance of PSCA as a novel prognostic marker and therapeutic target for cancer

One of the contributing factors in the diagnosis and treatment of most cancers is the identification of their surface antigens. Cancer tissues or cells have their specific antigens. Some antigens that are present in many cancers elicit different functions. One of these antigens is the prostate stem cell antigen (PSCA) antigen, which was first identified in the prostate. PSCA is a cell surface protein that has different functions in different tissues. It can play an inhibitory role in cell proliferation as well as a tumor-inducing role. PSCA has several genetic variants involved in cancer susceptibility in some tissues, so identifying the characteristics of this antigen and its relationship with clinical features can provide more information on diagnosis and treatment of patients with cancers. Most studies on the PSCA have focused on prostate cancer. While it is also expressed in other cancers, little attention has been paid to its role as a valuable diagnostic, prognostic, and therapeutic tool in other cancers. PSCA has several genetic variants that seem to play a significant role in cancer susceptibility in some tissues, so identifying the characteristics of this antigen and its relationship and variants with clinical features can be beneficial in concomitant cancer therapy and diagnosis, as theranostic tools. In this study, we will review the alteration of the PSCA expression and its polymorphisms and evaluate its clinical and theranostics significance in various cancers.

Sexual dimorphism in placental development and function: Comparative physiology with an emphasis on the pig

Across mammalian species, it has been demonstrated that sex influences birth weight, with males being heavier than females; a characteristic that can be observed from early gestation. Male piglets are more likely to be stillborn and have greater preweaning mortality than their female littermates, despite the additional maternal investment into male fetal growth. Given the conserved nature of the genome between the sexes, it is hypothesized that these developmental differences between males and females are most likely orchestrated by differential placental adaptation. This review summarizes the current understanding of fetal sex-specific differences in placental and endometrial structure and function, with an emphasis on pathways found to be differentially regulated in the pig including angiogenesis, apoptosis, and proliferation. Given the importance of piglet sex in agricultural enterprises, and the potential for skewed litter sex ratios, it is imperative to improve understanding of the relationship between fetal sex and molecular signaling in both the placenta and endometria across gestation.

Expression pattern Nanog is associated with the development of gestational trophoblastic neoplasia in Chinese women from Fujian province: a case-control study

BACKGROUND

Gestational trophoblastic disease (GTD) is a group of interrelated but distinct diseases and has a serious impact on the reproductive health of women. To analyze the expression of Nanog in GTD and to evaluate its potential to predict the development of gestational trophoblastic neoplasia (GTN).

METHODS

The study included 41 normal first-trimester placentas matched by gestational age to 53 regressed-hydatidiform-moles (rHMs), 56 malignant-HMs (mHMs) and 17 choriocarcinomas (CCAs) and evaluated the Nanog expression by immunohistochemistry. The chi-square test, ANOVA, Fisher's exact test and logistic regression were performed to assess the Nanog expression and clinical prognostic factors in GTD.

RESULTS

Compared to normal placenta levels, the Nanog expression was increased in GTD samples (p < .05). In HMs, Nanog expression was positively correlated with serum β-hCG levels,uterine size and theca-lutein cysts (p < .05). Compared with the low-risk metastatic group (Federation of Gynecology and Obstetrics (FIGO) score ≤ 6), the high-risk metastatic group (FIGO score >7) had higher Nanog expression (p = .030). Moreover, logistic regression analysis showed that the positive expression of Nanog had the highest risk of developing into GTN (OR = 4.764, p < .001).

CONCLUSIONS

Nanog is an independent predictor of clinical outcomes. It can also be a reliable predictor for GTN development from GTD.

MiR-30a-5p inhibits proliferation and metastasis of hydatidiform mole by regulating B3GNT5 through ERK/AKT pathways

Hydatidiform moles are gestational trophoblastic disease. They are abnormal proliferations of trophoblast cells that have the potential to become cancerous. miR-miR30a-5p is a tumour suppressor that participates in the development of numerous diseases. However, the role of miR-30a in hydatidiform moles and the mechanisms underlying its effects are presently unclear. This study explored the levels of miR-30a and B3GNT5 expression in human hydatidiform mole tissue. The results showed that miR-30a and B3GNT5 were differentially expressed in normal placenta and hydatidiform mole, and miR-30a decreased cell proliferation, invasion and migration in trophoblast cell lines. Upon further examination, it was confirmed that miR-30a directly targeted the 3'untranslated region of B3GNT5 using a dual-luciferase assay. The results of the present study also revealed that miR-30a reduced the proliferation, invasion and migration ability in JAR and BeWo cells by regulating B3GNT5, which may inactivate the ERK and AKT signalling pathways. This study demonstrated that miR-30a was a novel target B3GNT5 that serves an important role in the development of hydatidiform moles, suggesting that miR-30a may serve as a novel potential biomarker or useful diagnostic and therapeutic tool for hydatidiform moles in clinical settings.

Evaluation of serum M30 and M65 activity in patients with stage-I endometrial cancer

We aimed to analyse the prognostic value of serum oxidative stress parameters and apoptotic markers of serum M30/65 levels in endometrial cancer patients. Serum M30/65 levels and oxidative stress parameters were evaluated in 52 women with stage I endometrial cancer (n = 26) and a control group of healthy females (n = 26). The total antioxidant status (p = .002), oxidative stress index (p = .003) and serum M30/65 levels (p < .001) were significantly higher in women with stage-I endometrial cancer in comparison to the control group. Furthermore, serum M30/65 levels were significantly lower on postoperative day 8, compared to preoperative levels (p = .001 and p < .001, respectively), in the endometrial cancer group. Although impaired apoptotic activity plays a crucial role in the aetiopathogenesis of endometrial cancer, oxidative stress may be instrumental in malignant transformation. We concluded that measurement of M30/65 levels would be beneficial in the follow-up of women with endometrial cancer. Impact Statement What is already known on this subject: Although M30 has been evaluated as a marker of apoptosis in tissue samples from women with endometrial cancer (EC), no previous studies have simultaneously analysed serum M30 and M65 levels and oxidative stress in patients with stage-I EC. What the results of this study add: Total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI) and serum M30/65 levels were significantly higher in women with stage I EC in comparison to the control group. Furthermore, serum M30/65 levels were significantly lower on postoperative day 8, compared to preoperative levels, in the EC group. The fact that pre-operative M30/M65 levels were higher than the post-operative levels may be very important in early-stage EC What the implications are of these findings for clinical practice and/or further research: Although impaired apoptotic activity plays a crucial role in the aetiopathogenesis of EC, oxidative stress may be instrumental in malignant transformation. The fact that serum M30/M65 levels decreased in accordance with the reduction of post-operative tumour burden led us to conclude that measurement of M30/65 levels would be beneficial in the follow-up of women with EC.

P53 expression in various types of hydropic placentas (through ploidy analysis as a complementary tool in diagnosis of samples)

BACKGROUND

Placentas characterized by hydropic swelling of chorionic villi occur in a spectrum of pathological conditions including hydropic abortion (HA), partial hydatidiform mole (PHM) and complete hydatidiform mole (CHM). The purpose of this study was to investigate whether the expression of p53 tumour suppressor protein could differentiate these various types of hydropic placentas.

METHODS

p53 immunohistochemical staining was performed in 19 molar (8 PHM and 11 CHM) and 10 non-molar (HA) formalin-fixed, paraffin-embedded tissue samples. Ploidy analysis using flow cytometry was performed as a complementary tool in diagnosis of samples.

RESULTS

DNA histograms obtained from all samples had confirmed diploidy in HAs and CHMs and triploidy in PHMs. p53 immunoreactivity was assessed in villous cytotrophoblasts, syncytiotrophoblasts and stromal cells. The p53 positive reaction was predominantly observed in the nuclei of cytotrophoblastic cells and rarely in stromal cells, no reaction was seen in syncytiotrophoblasts. The mean percentage of p53 positive cells were 6.10±3.75 for HA, 25.87±13.4 for PHM and 39.83±18.76 for CHM. There was a significant difference in P53 immunoreactivity of cytotrophoblastic cells between CHM and HA (P<0.001), and between PHM and HA (P=0.004). There was no significant difference in immunohistochemical reactivity between CHM and PHM (P=0.068).

CONCLUSION

This study confirms that p53 immunostaining may be helpful in distinguishing complete and partial hydatidiform mole from hydropic abortion, but not complete hydatidiform mole from partial hydatidiform mole.

Associations between fetal size, sex and both proliferation and apoptosis at the porcine feto-maternal interface

Introduction

Inadequate fetal growth has severe consequences for both neonatal and adult development. It is hypothesised that the feto-maternal interface associated with the lightest and male fetuses will undergo more apoptosis and less proliferation than those supplying the closest to mean litter weight (CTMLW) and female fetuses respectively.

Methods

Placental and endometrial samples associated with the lightest and CTMLW (gestational day (GD) 18 and 30), male and female (GD45, 60 and 90) Large White X Landrace conceptuses or fetuses were obtained. The mRNA expression of candidate genes involved in apoptosis or proliferation (BAX, BCL2, P53 and KI67) was quantified by qPCR. TUNEL staining was performed on placental samples supplying the lightest and CTMLW fetuses (GD45 and 60), of both sex (GD60).

Results

Placentas associated with the lightest fetuses had decreased P53 and KI67 expression compared to the CTMLW fetuses at GD45. At GD60, P53 expression was increased in placentas supplying the lightest compared to CTMLW fetuses. P53 expression was increased in endometrial samples associated with the lightest compared to the CTMLW fetuses at GD45. At GD30 and GD60 respectively, BAX expression was increased and BCL2, P53 and KI67 expression were decreased in endometrial samples associated with females compared to their male littermates. TUNEL staining revealed no association between fetal size or sex, and apoptotic cell number.

Discussion

This study has highlighted dynamic associations between fetal size, sex, and apoptosis and proliferation at the porcine feto-maternal interface. Further studies should be performed to improve the understanding of the mechanisms behind these findings.

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Gestational day influence feto-maternal interface apoptotic mRNA expression.

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Fetal size is associated with feto-maternal interface apoptotic mRNA expression.

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Sexual dimorphism exists in feto-maternal interface apoptotic mRNA expression.

Daidzein induces choriocarcinoma cell apoptosis in a dose-dependent manner via the mitochondrial apoptotic pathway

Choriocarcinoma is a malignant gestational trophoblastic disease and relapse or drug resistance occurs in ~25% of gestational trophoblastic tumors. Cell apoptosis serves a role in the progression from hydatidiform mole to persistent gestational trophoblastic disease. It has been demonstrated that daidzein [7‑hydroxy‑3‑(4‑hydroxyphenyl)‑4H‑chromen‑4‑one] may induce apoptosis in a number of cancer types via the mitochondrial apoptotic pathway by altering the B‑cell lymphoma (Bcl)‑2/Bcl‑2 associated X, apoptosis regulator (Bax) ratio, and activating the caspase cascade. Daidzein also serves a role in regulation of production of human chorionic gonadotropin in trophoblast cells and inhibition of cell proliferation. However, few reports have been published regarding the effect of daidzein on apoptosis in choriocarcinoma. Therefore, in the present study, JAR and JEG‑3 human gestational choriocarcinoma cells were used to investigate the effect of daidzein on apoptosis of choriocarcinoma cells. Treatment with daidzein for 48 h reduced cell viability in a dose‑dependent manner. The percentages of early and late apoptotic cells also increased following treatment with daidzein in a dose‑dependent manner, with the number of late apoptotic cells increasing more prominently. Furthermore, treatment with daidzein led to apoptosis‑associated alterations in nuclear morphology of JAR and JEG-3 cells. Expression levels of cleaved poly(ADP‑ribose) polymerase, cleaved caspase‑3 and cleaved caspase‑9 increased following treatment with daidzein, whereas the Bcl‑2/Bax ratio decreased in a dose‑dependent manner. In conclusion, the results of the present study demonstrate that daidzein may induce apoptosis of choriocarcinoma cells in a dose‑dependent manner via the mitochondrial apoptotic pathway.

Morphological Features and Immunohistochemical Expression of p57Kip2 in Early Molar Pregnancies and Their Relations to the Progression to Persistent Trophoblastic Disease

Background

Although the morphological features characteristic of products of conception specimens including molar pregnancies are well described, substantial histopathological similarities are observed between the different entities, especially in cases of early pregnancies. Furthermore, there are no current solid criteria that could predict cases with progression to persistent gestational trophoblastic disease. In this study, we aimed to determine the most specific histopathological and immunohistochemical features required for accurate diagnosis that can reliably predict the clinical behavior.

Methods

Sixty-five cases of products of conception were reviewed clinically and pathologically, and any progression to persistent gestational trophoblastic disease (GTD), if present, was noted. Pathological assessment of the archival material included re-cut sections of 5 μm in thickness, routine staining with hematoxylin and eosin and immunohistochemical staining of p57Kip2.

Results

Certain histopathological criteria were found to be significant in differentiation between complete hydatidiform mole (CHM) and partial hydatidiform mole including villous shape and outline, villous trophoblast hyperplasia, and atypia in extravillous trophoblasts. There were no significant differences in any morphological or immunohistochemical features between cases with or without subsequent development of GTD.

Conclusions

Histopathological diagnosis of molar pregnancy remains problematic especially in early gestation. Their diagnosis should be stated after a constellation of specific histopathological criteria in order not to miss CHM. p57Kip2 immunohistochemistry is of great value in diagnosis of cases that had equivocal morphology by histopathological examination. However, there were no significant features to predict cases that subsequently developed persistent GTD.

Apoptotic index for prediction of postmolar gestational trophoblastic neoplasia

BACKGROUND

Although 85% of patients with a complete hydatidiform mole achieve spontaneous remission after a few months, 15% of them will experience gestational trophoblastic neoplasia, which requires chemotherapy. To date, there is no biomarker to predict post-molar gestational trophoblastic neoplasia before the initiation of human chorionic gonadotropin surveillance.

OBJECTIVE

The purpose of this study was to assess the relationship between the expression of apoptosis markers in the molar villous trophoblasts and the subsequent development of gestational trophoblastic neoplasia after the evacuation of a complete hydatidiform mole.

STUDY DESIGN

This was a retrospective cohort study of patients with complete hydatidiform mole who were diagnosed, treated, and followed at the Center of Trophoblastic Diseases (Botucatu/São Paulo State and Rio de Janeiro/Rio de Janeiro State, Brazil) from 1995-2014. Patients were divided temporally into derivation (1995-2004) and validation (2005-2014) cohorts. Immunohistochemistry was used to examine tissue expression of the apoptosis inhibitor survivin or the pro-apoptotic enzyme caspase-3. Survivin stains for cytoplasmic and nuclear expression were evaluated independently. Caspase-3 expression was measured as an apoptotic index of positive staining cells over negative staining cells multiplied by 100. Receiver operating characteristic curves were then constructed, and the area under the curve was calculated to test the performance characteristics of the staining to predict the subsequent development of gestational trophoblastic neoplasia.

RESULTS

The final study population comprised 780 patients, with 390 patients in each temporal cohort: 590 patients entered spontaneous remission, and 190 patients experienced post-molar gestational trophoblastic neoplasia. Neither nuclear nor cytoplasmic survivin expression performed well as a predictor of subsequent gestational trophoblastic neoplasia. The caspase-3 apoptotic index was a strong risk factor for subsequent gestational trophoblastic neoplasia development. When the apoptotic index was <4%, the risk of gestational trophoblastic neoplasia had an odds ratio of 35.55 (95% confidence interval, 14.02-90.14; P < .0001) in the derivation cohort and an odds ratio of 25.71 (95% confidence interval, 10.13-65.29; P < .0001) in the validation cohort. However, in both cohorts, the positive predictive value for gestational trophoblastic neoplasia of an apoptotic index <4.0% was modest (49% in the derivation cohort and 41% in the validation cohort); the negative predictive value for gestational trophoblastic neoplasia of an apoptotic index ≥4.0% was high (97% in both cohorts).

CONCLUSION

The subsequent development of gestational trophoblastic neoplasia after evacuation of complete hydatidiform mole is tied closely to the apoptotic index, which may be a useful biomarker for future prospective studies.

Expression patterns of maspin and mutant p53 are associated with the development of gestational trophoblastic neoplasia

Gestational trophoblastic disease (GTD) is a group of conditions that originate from the abnormal proliferation of trophoblastic cells. GTDs encompass hydatidiform moles (HMs) and gestational trophoblastic neoplasia (GTN). GTNs are a group of malignant diseases that require chemotherapy, or more aggressive treatment. There is a requirement for more tumor markers to predict the development of GTN from HMs. The current study evaluated the expression of maspin and tumor protein p53 (p53) in GTD, and their role in predicting the development of GTN. Expression of maspin and mutant p53 (m-p53) was detected by immunohistochemistry in 48 normal first trimester placentas, matched for gestational age to 49 HMs that regressed, 39 malignant HMs and 11 invasive moles or choriocarcinomas. Spearman's rank correlation analysis and logistic regression were performed on the expression patterns of maspin and m-p53, and on the clinical prognostic factors in GTD. Compared with normal placenta levels, the expression levels of maspin were decreased, whereas the expression levels of m-p53 were increased in GTDs (P<0.05). The expression levels of maspin and m-p53 in complete and partial HMs were not significantly different (P>0.05). In HMs, maspin expression was inversely correlated with serum β human chorionic gonadotropin, uterine size and diameter of theca-lutein cysts; however, m-p53 expression demonstrated a positive correlation with these factors (all P<0.05). Compared with the high-risk metastatic group (FIGO score ≥7), the low-risk group (FIGO score <7) exhibited a higher rate of positive maspin expression (P=0.041), and the frequency of positive m-p53 expression was significantly higher in patients with an advanced FIGO stages (FIGO stage ≥III) compared with patients in early stages (FIGO stage ≤II; 87.9 vs. 58.8%; P=0.019). The combination of maspin negative expression with m-p53 positive expression had an 84% specificity value, 76% positive predictive value and 70% negative predictive value for the development of GTN. In conclusion, maspin-negative and m-p53-positive expression is associated with the development of GTN in HMs.

FBI-1 Is Overexpressed in Gestational Trophoblastic Disease and Promotes Tumor Growth and Cell Aggressiveness of Choriocarcinoma via PI3K/Akt Signaling

Human placental trophoblasts can be considered pseudomalignant, with tightly controlled proliferation, apoptosis, and invasiveness. Gestational trophoblastic disease (GTD) represents a family of heterogeneous trophoblastic lesions with aberrant apoptotic and proliferative activities and dysregulation of cell signaling pathways. We characterize the oncogenic effects of factor that binds to the inducer of short transcripts of HIV-1 [FBI-1, alias POZ and Krüppel erythroid myeloid ontogenic factor (POKEMON)/ZBTB7A] in GTD and its role in promoting cell aggressiveness in vitro and tumor growth in vivo. IHC studies showed increased nuclear expression of FBI-1, including hydatidiform moles, choriocarcinoma (CCA), and placental site trophoblastic tumor, in GTD. In JAR and JEG-3 CCA cells, ectopic FBI-1 expression opposed apoptosis through repression of proapoptotic genes (eg, BAK1, FAS, and CASP8). FBI-1 overexpression also promoted Akt activation, as indicated by Akt-pS473 phosphorylation. FBI-1 overexpression promoted mobility and invasiveness of JEG-3 and JAR, but not in the presence of the phosphoinositide 3-kinase inhibitor LY294002. These findings suggest that FBI-1 could promote cell migration and invasion via phosphoinositide 3-kinase/Akt signaling. In vivo, nude mice injected with CCA cells with stable FBI-1 knockdown demonstrated reduced tumor growth compared with that in control groups. These findings suggest that FBI-1 is clinically associated with the progression of, and may be a therapeutic target in, GTD, owing to its diverse oncogenic effects on dysregulated trophoblasts.

Modulation of Decidual Macrophage Polarization by Macrophage Colony-Stimulating Factor Derived from First-Trimester Decidual Cells: Implication in Preeclampsia

During human pregnancy, immune tolerance of the fetal semiallograft occurs in the presence of abundant maternal leukocytes. At the implantation site, macrophages comprise approximately 20% of the leukocyte population and act as primary mediators of tissue remodeling. Decidual macrophages display a balance between anti-inflammatory and proinflammatory phenotypes. However, a shift to an M1 subtype is reported in preeclampsia. Granulocyte-macrophage colony-stimulating-factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF) are major differentiating factors that mediate M1 and M2 polarization, respectively. Previously, we observed the following: i) the preeclamptic decidua contains an excess of both macrophages and GM-CSF, ii) the preeclampsia-associated proinflammatory cytokines, IL-1β and tumor necrosis factor-α, markedly enhance GM-CSF and M-CSF expression in cultured leukocyte-free first-trimester decidual cells (FTDCs), iii) FTDC-secreted GM-CSF polarizes macrophages toward an M1 subtype. The microenvironment is a key determinant of macrophage phenotype. Thus, we examined proinflammatory stimulation of FTDC-secreted M-CSF and its role in macrophage development. Immunofluorescence staining demonstrated elevated M-CSF-positive decidual cell numbers in preeclamptic decidua. In FTDCs, IL-1β and tumor necrosis factor-α signal through the NF-κB pathway to induce M-CSF production, which does the following: i) enhances differentiation of and elevates CD163 expression in macrophages, ii) increases macrophage phagocytic capacity, and iii) inhibits signal-regulatory protein α expression by macrophages. These findings suggest that FTDC-secreted M-CSF modulates the decidual immune balance by inducing M2 macrophage polarization and phagocytic capacity in response to proinflammatory stimuli.

Can circulating M30 and M65 levels be beneficial markers in the diagnosis and management of patients with complete hydatidiform mole?

OBJECTIVE

The objective of this study is to evaluate the prognostic value of M30 and M65 levels as markers of apoptotic activity and maternal serum oxidative stress in patients with complete hydatidiform mole (CHM).

METHODS

In total, 68 pregnant women were included in the study. The study group included 34 pregnant with CHM, while 34 healthy pregnant were employed as a control group. Venous blood samples were drawn to assess the maternal serum oxidative stress and M30-M65 levels. In addition, a second blood sample was drawn from patients with CHM on day 8 after dilatation evacuation.

RESULTS

Maternal serum oxidative stress and M30-M65 levels were found to be significantly higher in patients with CHM as compared with the control group. It was found that serum β-subunit of human chorionic gonadotropin (β-hCG) level had a significant positive correlation with M30-M65 levels in patients with CHM. In addition, serum M65 level was found to be as effective as β-hCG in the identification of the patients with CHM.

CONCLUSION

Our results indicated that oxidative stress and apoptosis may play significant roles in CHM development. In addition, it seems that serum M30-M65 levels can presumably be an ancillary laboratory test to β-hCG in the diagnosis and follow-up of the patients with CHM.

Downregulation of ASPP2 in choriocarcinoma contributes to increased migratory potential through Src signaling pathway activation

Gestational choriocarcinoma is a malignant tumor derived from placental trophoblast and the most aggressive member of gestational trophoblastic disease (GTD). Apoptosis-stimulating protein of p53-2 (ASPP2) is a member of ASPP family that transactivates p53 and thereby functions as a tumor suppressor. In this study, the expression profile of ASPP2 in choriocarcinoma was examined in comparison with normal placentas and hydatidiform moles, the latter being a type of GTD that carries malignant potential. Downregulation of ASPP2 messenger RNA and protein was demonstrated in choriocarcinoma by quantitative PCR and immunohistochemistry. ASPP2-transfected choriocarcinoma cells (JEG-3 and JAR) showed an increase in apoptosis and a decrease in cell migration as detected by TdT-mediated dUTP nick end labeling and wound healing assays, respectively, illustrating the complex action of ASPP2 on cell functions other than programmed cell death. Activated Src is known to be important in tumor progression. Transfection of ASPP2 but not ASPP1, another tumor-suppressive ASPP, was found to be related to subsequent decreased Src-pY416 phosphorylation, suggesting an inactivating effect of ASPP2 on Src. Moreover, this ASPP2-mediated inactivation of Src could be abolished by RNA interference with C-terminal Src kinase (Csk), a kinase that can inhibit Src activation. Our findings suggested that the ability of ASPP2 to attenuate Src activation was specific to ASPP2 in a Csk-dependent manner. Taken together, we demonstrated a loss of tumor-suppressive ASPP2 in choriocarcinoma with effects on cell migration and apoptosis. We also unveiled a possible mechanistic link between ASPP2 and Csk/Src signaling pathway, implicating the multiple cellular functions of ASPP2.

Melatonin: the smart killer: the human trophoblast as a model

Melatonin has both the ability to induce intrinsic apoptosis in tumor cells while it inhibits it in non-tumor cells. Melatonin kills tumor cells through induction of reactive oxygen species generation and activation of pro-apoptotic pathways. In contrast, melatonin promotes the survival of non-tumor cells due to its antioxidant properties and the inhibition of pro-apoptotic pathways. In primary human villous trophoblast, a known pseudo-tumorigenic tissue, melatonin promotes the survival through inhibition of the Bax/Bcl-2 pathway while in BeWo choriocarcinoma cell line melatonin induces permeabilization of the mitochondrial membrane leading to cellular death. These findings suggest that the trophoblast is a good model to study the differential effects of melatonin on the intrinsic apoptosis pathway. This review describes the differential effects of melatonin on the intrinsic apoptosis pathway in tumor and non-tumor cells and presents the trophoblast as a novel model system in which to study these effects of melatonin.

Pro-inflammatory cytokine-stimulated first trimester decidual cells enhance macrophage-induced apoptosis of extravillous trophoblasts

OBJECTIVE

As human blastocyst-derived extravillous trophoblasts (EVTs) invade the early decidua, they are positioned to interact with immune cells and resident decidual cells, and remodel spiral arteries into high capacity vessels that increase blood flow to the developing fetal-placental unit. Shallow EVT invasion elicits incomplete vascular transformation and reduces uteroplacental blood flow that presages adverse pregnancy outcomes. Excess macrophages in the decidua induce EVT apoptosis via tumor necrosis factor-alpha (TNF-α) secretion. Our previous observation that pro-inflammatory cytokines enhance neutrophil and macrophage activator granulocyte-macrophage colony-stimulating factor (GM-CSF) expression in first trimester decidual cells is now extended to include: (1) the specific macrophage activator M-CSF; (2) macrophage activation and subsequent enhancement of EVT apoptosis by both GM-CSF and M-CSF.

STUDY DESIGN

Quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay assessed M-CSF expression in first trimester decidual cells incubated with interleukin-1 beta (IL-1β) or TNF-α. Peripheral monocyte-derived macrophages pre-incubated with conditioned media from decidual cell cultures were co-cultured with a first trimester EVT cell line, HTR-8/SVneo cells. Macrophage activation was examined and EVT apoptosis evaluated by DNA fragmentation, caspase activation and cell membrane asymmetry.

RESULTS

IL-1β or TNF-α significantly enhanced M-CSF expression in first trimester decidual cells. The conditioned media from these cultures activates macrophages, which promote caspase 3/7-dependent EVT apoptosis with antibodies against GM-CSF or M-CSF blocking this effect.

CONCLUSIONS

Pro-inflammatory cytokines increases synthesis of M-CSF in first trimester decidual cells. Both GM-CSF and M-CSF activate macrophages, which initiate caspase-dependent EVT apoptosis.

Downregulation of ASPP1 in gestational trophoblastic disease: correlation with hypermethylation, apoptotic activity and clinical outcome

Gestational trophoblastic disease encompasses a spectrum of trophoblastic lesions including true neoplasms such as choriocarcinomas and the potentially malignant hydatidiform moles, which may develop persistent disease requiring chemotherapy. ASPP1, a member of apoptosis-stimulating proteins of p53 (ASPPs), is a proapoptotic protein that can stimulate apoptosis through its interaction with p53. We evaluated the promoter methylation and expression profiles of ASPP1 in different trophoblastic tissues and its in vitro functional effect on two choriocarcinoma cell lines, namely JEG-3 and JAR. Significant downregulation of ASPP1 mRNA and protein levels was demonstrated in hydatidiform moles and choriocarcinomas, when compared with normal placentas by quantitative-PCR and immunohistochemistry. The ASPP1 mRNA level was significantly correlated with its hypermethylation status, evaluated with methylation-specific PCR, in placenta and gestational trophoblastic disease samples (P=0.024). Moreover, lower ASPP1 immunoreactivity was shown in hydatidiform moles that progressed to persistent gestational trophoblastic neoplasms than in those that regressed (P=0.045). A significant correlation was also found between expression of ASPP1 and proliferative indices (assessed by Ki67 and MCM7), apoptotic activity (M30 CytoDeath antibody), p53 and caspase-8 immunoreactivities. An in vitro study showed that ectopic expression of ASPP1 could trigger apoptosis through intrinsic and extrinsic pathways as indicated by an increase in cleaved caspase-9 and Fas ligand protein expression. The latter suggests a hitherto unreported novel link between ASPP1 and the extrinsic pathway of apoptosis. Our findings suggest that downregulation of ASPP1 by hypermethylation may be involved in the pathogenesis and progress of gestational trophoblastic disease, probably through its effect on apoptosis.

Placental apoptosis in health and disease

Apoptosis, programmed cell death, is an essential feature of normal placental development but is exaggerated in association with placental disease. Placental development relies upon effective implantation and invasion of the maternal decidua by the placental trophoblast. In normal pregnancy, trophoblast apoptosis increases with placental growth and advancing gestation. However, apoptosis is notably exaggerated in the pregnancy complications, hydatidiform mole, pre-eclampsia, and intrauterine growth restriction (IUGR). Placental apoptosis may be initiated by a variety of stimuli, including hypoxia and oxidative stress. In common with other cell-types, trophoblast apoptosis follows the extrinsic or intrinsic pathways culminating in the activation of caspases. In contrast, the formation of apoptotic bodies is less clearly identified, but postulated by some to involve the clustering of apoptotic nuclei and liberation of this material into the maternal circulation. In addition to promoting a favorable maternal immune response, the release of this placental-derived material is thought to provoke the endothelial dysfunction of pre-eclampsia. Widespread apoptosis of the syncytiotrophoblast may also impair trophoblast function leading to the reduction in nutrient transport seen in IUGR. A clearer understanding of placental apoptosis and its regulation may provide new insights into placental pathologies, potentially suggesting therapeutic targets.

Pathogenesis of choriocarcinoma: clinical, genetic and stem cell perspectives

Choriocarcinoma is a unique malignant neoplasm composed of mononuclear cytotrophoblasts and multinucleated syncytiotrophoblasts that produce human chorionic gonadotrophin. Choriocarcinoma can occur after a pregnancy, as a component of germ cell tumors, or in association with a poorly differentiated somatic carcinoma, each with distinct clinical features. Cytogenetic and molecular studies, predominantly on gestational choriocarcinoma, revealed the impact of oncogenes, tumor suppressor genes and imprinting genes on its pathogenesis. The role of stem cells in various types of choriocarcinoma has been studied recently. This review will discuss how such knowledge can enhance our understanding of the pathogenesis of choriocarcinoma, enable exploration of novel anti-choriocarcinoma targeted therapy and possibly improve our insight on embryological and placental development.

Circulating cell death products predict clinical outcome of colorectal cancer patients

BACKGROUND

Tumor cell death generates products that can be measured in the circulation of cancer patients. CK18-Asp396 (M30 antigen) is a caspase-degraded product of cytokeratin 18 (CK18), produced by apoptotic epithelial cells, and is elevated in breast and lung cancer patients.

METHODS

We determined the CK18-Asp396 and total CK18 levels in plasma of 49 colorectal cancer patients, before and after surgical resection of the tumor, by ELISA. Correlations with patient and tumor characteristics were determined by Kruskal-Wallis H and Mann-Whitney U tests. Disease-free survival was determined using Kaplan-Meier methodology with Log Rank tests, and univariate and multivariate Cox proportional hazard analysis.

RESULTS

Plasma CK18-Asp396 and total CK18 levels in colorectal cancer patients were related to disease stage and tumor diameter, and were predictive of disease-free survival, independent of disease-stage, with hazard ratios (HR) of patients with high levels (> median) compared to those with low levels (< or = median) of 3.58 (95% CI: 1.17-11.02) and 3.58 (95% CI: 0.97-7.71), respectively. The CK18-Asp396/CK18 ratio, which decreased with tumor progression, was also predictive of disease-free survival, with a low ratio (< or = median) associated with worse disease-free survival: HR 2.78 (95% CI: 1.06-7.19). Remarkably, the plasma CK18-Asp396 and total CK18 levels after surgical removal of the tumor were also predictive of disease-free survival, with patients with high levels having a HR of 3.78 (95% CI: 0.77-18.50) and 4.12 (95% CI: 0.84-20.34), respectively, indicating that these parameters can be used also to monitor patients after surgery.

CONCLUSION

CK18-Asp396 and total CK18 levels in the circulation of colorectal cancer patients are predictive of tumor progression and prognosis and might be helpful for treatment selection and monitoring of these patients.

Activated Stat3 expression in gestational trophoblastic disease: correlation with clinicopathological parameters and apoptotic indices

AIMS

To assess the expression profile of the activated form of signal transducer and activator of transcription (Stat)3 in gestational trophoblastic disease (GTD) and correlate the findings with clinicopathological parameters.

METHODS AND RESULTS

By immunohistochemistry, both cytoplasmic and nuclear expression of p-Stat3-Ser(727) was demonstrated in 88 trophoblastic tissues, including placentas and GTD. Nuclear immunoreactivity of p-Stat3-Ser(727) was significantly higher in hydatidiform mole (HM) (P < 0.001) and choriocarcinoma (P = 0.009) when compared with normal placentas. Placental site trophoblastic tumours (PSTT) and epithelioid trophoblastic tumours (ETT) also demonstrated higher nuclear p-Stat3-Ser(727) expression than their normal trophoblast counterparts. Higher p-Stat3-Ser(727) expression was confirmed in choriocarcinoma cell lines, JEG-3 and JAR, than in a normal trophoblast cell line, with both nuclear and cytoplasmic fractions demonstrated by immunoblotting. Spontaneously regressed HM showed significantly increased nuclear and cytoplasmic p-Stat3-Ser(727) immunoreactivity over those that developed gestational trophoblastic neoplasia (GTN) (P = 0.013, P = 0.039). There was a significant positive and inverse correlation between nuclear p-Stat3-Ser(727) immunoreactivity and apoptotic indices [terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick end labelling and M30 CytoDeath antibody] (P = 0.001, P < 0.001, Spearman's rho test) and Bcl-2 expression (P = 0.034), respectively.

CONCLUSIONS

p-Stat3-Ser(727) plays a role in the pathogenesis of GTD, probably through the regulation of apoptosis. p-Stat3-Ser(727) immunoreactivity is a potential marker in predicting GTN in HM.

Overexpression of NANOG in gestational trophoblastic diseases: effect on apoptosis, cell invasion, and clinical outcome

Gestational trophoblastic disease includes choriocarcinoma, a frankly malignant tumor, and hydatidiform mole (HM), which often leads to the development of persistent gestational trophoblastic neoplasia and requires chemotherapy. NANOG is an important transcription factor that is crucial for maintaining embryonic stem cell self-renewal and pluripotency. We postulated that NANOG is involved in the pathogenesis of gestational trophoblastic disease. In this study, significantly higher NANOG mRNA and protein expression levels, by quantitative PCR and immunoblotting, respectively, were demonstrated in HMs, particularly those that developed persistent disease, when compared with normal placentas. In addition, significantly increased nuclear NANOG immunoreactivity was found by immunohistochemistry in HMs (P < 0.001) and choriocarcinoma (P = 0.002). Higher NANOG expression levels were demonstrated in HMs that developed persistent disease, as compared with those that regressed (P = 0.025). Nuclear localization of NANOG was confirmed by confocal microscopy and immunoblotting in choriocarcinoma cell lines. There was a significant inverse correlation between NANOG immunoreactivity and apoptotic index assessed by M30 CytoDeath antibody (P = 0.012). After stable knockdown of NANOG in the choriocarcinoma cell line JEG-3 by an shRNA approach, increased apoptosis was observed in relation to with enhanced caspases and poly(ADP-ribose) polymerase activities. NANOG knockdown was also associated with decreased mobility and invasion of JEG-3 and down-regulation of matrix metalloproteases 2 and 9. These findings suggest that NANOG is involved in the pathogenesis and clinical progress of gestational trophoblastic disease, likely through its effect on apoptosis, cell migration, and invasion.

Live and let die - regulation of villous trophoblast apoptosis in normal and abnormal pregnancies

Since 1995 the number of publications investigating apoptosis in villous trophoblast has increased exponentially. This scientific interest is in part due to observations that this specialised form of cell death is increased in pregnancy complications such as pre-eclampsia and intra-uterine growth restriction. In addition, apoptosis is described in normal villous trophoblast and elements of the apoptotic machinery are involved in the fusion between cytotrophoblast and the overlying multinucleate syncytiotrophoblast. The increase in descriptions of apoptotic cell death in villous trophoblast has been accompanied by investigations of regulators of apoptosis. It is anticipated that understanding the regulation of apoptosis in villous trophoblast may provide new insights into placental pathologies. This review describes current knowledge regarding the expression and function of these regulators in villous trophoblast, both in normal and complicated pregnancies.

Resveratrol imparts photoprotection of normal cells and enhances the efficacy of radiation therapy in cancer cells

Solar radiation spans a whole range of electromagnetic spectrum including UV radiation, which are potentially harmful to normal cells as well as ionizing radiations which are therapeutically beneficial towards the killing of cancer cells. UV radiation is an established cause of a majority of skin cancers as well as precancerous conditions such as actinic keratosis. However, despite efforts to educate people about the use of sunscreens and protective clothing as preventive strategies, the incidence of skin cancer and other skin-related disorders are on the rise. This has generated an enormous interest towards finding alternative approaches for management of UV-mediated damages. Chemoprevention via nontoxic agents, especially botanical antioxidants, is one such approach that is being considered as a plausible strategy for prevention of photodamages including photocarcinogenesis. In this review, we have discussed the photoprotective effects of resveratrol, an antioxidant found in grapes and red wine, against UVB exposure-mediated damages in vitro and in vivo. In addition, we have also discussed studies showing that resveratrol can act as a sensitizer to enhance the therapeutic effects of ionizing radiation against cancer cells. Based on available literature, we suggest that resveratrol may be useful for (1) prevention of UVB-mediated damages including skin cancer and (2) enhancing the response of radiation therapies against hyperproliferative, precancerous and neoplastic conditions.

The pathology of gestational trophoblastic disease: recent advances

When inundated with numerous specimens of products of conception as the consequence of miscarriage, it is all too easy for histopathologists to forget that the biology of trophoblast and the events of early placental implantation continue to fascinate because of the inherently invasive properties of the non-villous (extravillous) trophoblast. However, unlike the invasion of a malignant tumour, the invasion of trophoblast is controlled. The failure of adequate conversion of maternal uteroplacental arteries is a major pathogenetic phenomenon of important disorders of pregnancy including pre-eclampsia. However, it is in the field of gestational trophoblastic disease that diagnostic acumen is most called for. There are several problematic areas that give rise to diagnostic error; e.g., the diagnosis of early complete mole as partial mole, the over-diagnosis of hydatidiform mole in tubal pregnancy and the diagnosis of placental site non-villous trophoblast as placental site trophoblastic tumour or choriocarcinoma, particularly if associated with atypia, as frequently observed in complete mole. The chorionic villi of early diploid complete mole show characteristic features of villous profile, stromal mucin and stromal nuclear debris. The distinction between complete mole and triploid partial mole can be facilitated by ploidy analysis and immunohistochemistry for the product of the paternally imprinted, maternally expressed gene, p57kip2. Persistent trophoblastic disease (PTD) is a clinical not a histopathological diagnosis and the role of the histopathologist once a diagnosis of PTD has been made is limited. Invasive mole and choriocarcinoma are encompassed by PTD. Tumours of the non-villous trophoblast are placental site trophoblastic tumour and the more recently recognised epithelioid trophoblastic tumour. The role of immunohistochemistry in the elucidation of trophoblastic lesions is discussed pragmatically.

Response to neoadjuvant chemotherapy in breast cancer could be predictable by measuring a novel serum apoptosis product, caspase-cleaved cytokeratin 18: a prospective pilot study

The M30-monoclonal antibody recognizes a neo-epitope of cytokeratin 18 which is formed after caspase-cleavage during apoptosis. Caspase-cleaved cytokeratin 18 is released from apoptotic cells into circulation. The aim of this study was to evaluate the relationship between M30-antigen level and chemotherapy response in neoadjuvant treatment of breast cancer. Forty-two patients with invasive breast carcinoma received 4 cycles of anthracycline based neoadjuvant chemotherapy. Serum samples were obtained for assessment of M30-antigen levels before the administration of first chemotherapy cycle (baseline), and then after 24 and 48 hours for determination of chemotherapy induced apoptosis. M30-antigen levels at 24 and 48 hours were found to be significantly higher than baseline (p < 0.001, p = 0.003, respectively). M30-antigen levels in responders showed statistically significant increases at 24 and 48 hours (p < 0.001; p = 0.004, respectively), while statistically significant increases were not observed in nonresponders. Percentage change of M30-antigen levels was significantly higher in responders than nonresponders at 24 hours (p = 0.020). In conclusion, our study revealed a significant relationship between increases of M30-antigen levels in serum and overall response to therapy.

Expression of maspin in gestational trophoblastic disease

BACKGROUND

Maspin is a tumor suppressor gene whose expression is altered in neoplasia and malignancies of many tissues. In the human placenta, the maspin gene is expressed in trophoblastic cells and might act as an inhibitory regulator of trophoblastic invasion. Hence, in gestational trophoblastic disease (GTD), where there is increased propensity for invasion in the trophoblastic tissue, we hypothesized that maspin expression would be decreased. The present study aimed at investigating the expression of maspin in GTD and its prognostic significance.

METHODS

Using immunohistochemical staining, we firstly studied the expression of maspin in hydatidiform moles, with gestational age-matched normal first trimester placenta used as control. A total of 38 cases of hydatidiform moles were studied, including 20 complete moles (CM) and 18 partial moles (PM). Among them, 10 cases of the CM group and 8 cases of the PM group subsequently developed gestational trophoblastic neoplasia (GTN). Immunostaining was also performed on tissue from 4 cases of choriocarcinoma and 5 cases of placental site trophoblastic tumor. Reverse transcriptase-polymerase chain reaction (RT-PCR) was further performed on RNA extracted from 10 hydatidiform moles (5 with GTN and 5 without) and 6 normal first-trimester placentae.

RESULTS

In all tissue sections, nuclear expression of immunostaining signal was demonstrated, mainly in the cytotrophoblasts. The percentage of trophoblastic nuclei stained in both complete and partial moles was significantly lower than that in normal first-trimester placenta (P < 0.001). However, there was no significant difference in immunostaining between complete and partial moles (P > 0.05). There was also significantly lower expression of maspin in those cases subsequently developing GTN than those which did not (P = 0.01). Immunostaining on choriocarcinoma and placental site trophoblastic tumor showed reduced expression of maspin in all the tumor cells. Reverse transcriptase-polymerase chain reaction revealed that the expression of maspin was consistently down-regulated in all the hydatidiform mole samples.

CONCLUSIONS

Our results suggest that there is down-regulated expression of maspin in gestational trophoblastic diseases, and the down-regulation is more prominent in cases developing gestational trophoblastic neoplasia. This may play a role with prognostic significance in the pathogenesis and malignant transformation of hydatidiform moles.

Differential Gene Expression Identified in Complete Hydatidiform Mole by Combining Suppression Subtractive Hybridization and cDNA Microarray

Complete hydatidiform mole (CHM) is a type of gestational trophoblastic disease with pure paternal chromosome contribution and unpredictable malignant potential. As an attempt to assess the molecular pathogenesis of CHM, suppression subtractive hybridization (SSH) combined with cDNA microarray was used to compare the gene expression pattern of CHM compared with normal first-trimester placenta of similar gestational ages. cDNA microarray analysis using tissue-specific chips constructed with subtracted cDNA libraries identified 13 differentially expressed gene transcripts. Quantitative real-time polymerase chain reaction (PCR) confirmed up-regulation of human chorionic gonadotropin beta subunit (CGB) (P=0.0008) and KIAA1200 (P=0.0005), a G-protein regulator, as well as down-regulation of osteopontin (SPP1) (P<0.0001) in 14 genotyped CHM when compared with 15 normal placentas. These candidate genes may contribute toward understanding the mechanism involved with the development and progression of CHM.

Detection of epithelial cell death in the body by cytokeratin 18 measurement

Cell death is as important as cell division in both physiological and pathological processes. Three major types of cell death have been described: apoptosis, autophagy and necrosis. Apoptosis is a form of programmed cell death, mediated by caspases. Autophagy is an evolutionarily conserved process involving lysosomes, implicated in both cell survival and death. Necrosis is believed to be an unregulated process, followed by release of intracellular components. The epithelial-specific intermediate filament cytokeratin 18 (Kl8) has different fates depending on the type of cell death. During apoptosis, K18 is cleaved at two sites into three fragments, one of which is specifically recognized by the monoclonal antibody, M30. During autophagy K18 is reported to stay uncleaved. Necrotic cells are considered to release K18. Thus, serum levels of different forms of K18 would reflect the type of cell death occurring in the body. Two enzyme-linked immunosorbent assays have been developed: one for the cleaved fragments of K18 and the other for total K18. Detection of serum levels of cleaved and total K18 showed that the ratios between cleaved and total K18 were highly variable among patients with endometrial cancer. Monitoring serum levels of cleaved and total K18 during chemotherapy showed an association between increases in total K18 levels and clinical responses. Monitoring serum levels of K18 may be a promising approach for early detection of therapeutic effects and the levels of different forms of K18 might indicate the mode of cell death occurring in the body.

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.

Effect of all-trans retinoic acid on tissue dynamics of choriocarcinoma cell lines: an organotypic model

BACKGROUND

All-trans retinoic acid (ATRA) is a natural vitamin A derivative that has a profound effect on the regulation of cell growth, differentiation and death.

AIM

To investigate the tissue dynamic and cellular invasion effects of ATRA in choriocarcinoma (CCA), an aggressive trophoblastic tumour, by using a three-dimensional organotypic culture model system and cell invasion assay, respectively.

METHODS

An organotypic culture model of two CCA cell lines, JAR and JEG, was established. The effects of 1 microM ATRA on proliferation, differentiation and apoptosis on this CCA model were assessed by morphological assessment of the mitotic and apoptotic figures as well as by Ki-67 and caspase-related M30 cytoDeath antibody immunohistochemistry and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) assay. The effect of ATRA on p53 and its regulated protein product, WAF1/Cip1, was also evaluated with DO7 and p21(WAF1) antibodies, respectively. Moreover, the effect of ATRA on cellular (CCA) invasion was also investigated with Cell Invasion Kit on the JEG cell line.

RESULTS

ATRA was found to induce marked apoptosis in organotypic cultures of both cell lines, as evidenced by increased M30-positive cells (p<0.0001) and increased TUNEL-positive cells (p<0.0001) in treated cultures; to decrease proliferation, as evidenced by decreased Ki-67-positive cells (p<0.0001); and to decrease p53-DO7 immunoreactivity (p<0.0001) and increase p21(WAF1) (p<0.0001) immunoreactivity. 1.5 microM ATRA was found to effectively inhibit JEG cell invasion in the cell invasion assay.

CONCLUSION

ATRA treatment was found to inhibit invasion and proliferation and enhance apoptosis, probably by the activation of caspases and induction of differentiation. ATRA and synthetic retinoids may be alternative agents for the treatment of CCA.

Mutations in NALP7 cause recurrent hydatidiform moles and reproductive wastage in humans

Hydatidiform mole (HM) is an abnormal human pregnancy with no embryo and cystic degeneration of placental villi. We report five mutations in the maternal gene NALP7 in individuals with familial and recurrent HMs. NALP7 is a member of the CATERPILLER protein family involved in inflammation and apoptosis. NALP7 is the first maternal effect gene identified in humans and is also responsible for recurrent spontaneous abortions, stillbirths and intrauterine growth retardation.

Id helix-loop-helix proteins are differentially expressed in gestational trophoblastic disease

AIMS

To assess the expression of Id proteins in trophoblastic tissues and to correlate this with clinical parameters, proliferative and apoptotic indices as well as to related oncogene expression.

METHODS AND RESULTS

Immunohistochemistry for Id1, Id2, Id3 and Id4 was performed on 83 trophoblastic tissues including 17 normal first-trimester placentas, seven term placentas, 47 hydatidiform moles (HM), and 12 spontaneous miscarriages. The four Id proteins were predominantly expressed in the villous and implantation site intermediate trophoblast. Expression of Id1 in HM was significantly higher than that in normal placenta (P = 0.0006) and spontaneous miscarriage (P = 0.0001) but did not correlate with subsequent development of gestational trophoblastic neoplasia (GTN). Id1 expression correlated with the proliferation index as assessed by MCM7 (P = 0.003) and Ki67 (P = 0.017) and with the apoptotic activity assessed by TUNEL (P = 0.001) and M30 CytoDeath antibody (P = 0.013). Moreover, the expression of Id1 correlated with the expression of p53 (P = 0.004), p21(WAF1) (/CIP1) (P = 0.003) but not with p16 (P = 0.107).

CONCLUSIONS

Id proteins may play a role in the regulation of proliferative and apoptotic activity in trophoblastic tissue and are potentially useful in differentiating molar and non-molar gestation, but are not helpful in predicting GTN.

Inhibition of DLX4 promotes apoptosis in choriocarcinoma cell lines

Homeodomain (HDM) proteins encoded by homeobox (HBX) genes represent a large family of transcriptional factors that control differentiation and development in certain cell types. DLX4 is a member of Distal-less (DLX) family of HBX genes. Recent studies have demonstrated that abnormal expression of DLX4 is present in several types of human tumors, such as breast cancer, leukemia and colon cancer. In the present study, we investigated DLX4 mRNA and protein expression in both normal placental tissues and human choriocarcinoma cell lines. Also, using RNA interference (RNAi) technique, we knocked down the expression of DLX4 and examined apoptosis in JEG-3 cells. Our studies demonstrated that DLX4 RNAi inhibited DLX4 mRNA expression and decreased DLX4 protein mass specifically and effectively, potentially enhancing apoptosis. Moreover, we examined expression of caspase-3 and caspase-8, and found that both caspases were increased after DLX4 knockdown. However, DLX4 RNAi did not influence Bax expression in JEG-3 cells. In conclusion, this study suggests that DLX4 may be involved in the survival of human choriocarcinoma cells, which may be mediated by the inhibition of apoptosis. The detailed mechanism needs further investigation.

Promoter hypermethylation of multiple genes in hydatidiform mole and choriocarcinoma

The methylation status of genes in hydatidiform mole and choriocarcinoma and its significance is relatively unexplored. We investigated the methylation status of the promoter regions of six genes, p16, HIC-1, TIMP3, GSTP1, death-associated protein kinase (DAPK), and E-cadherin in 54 hydatidiform moles, five choriocarcinomas, and 10 first trimester placenta by methylation-specific polymerase chain reaction (PCR). Immunohistochemical expression of p16, TIMP3, and E-cadherin, and quantitative real-time RT-PCR of p16 was also performed. Among the six genes examined, the promoter region of four genes (E-cadherin, HIC-1, p16, TIMP3) in choriocarcinoma and three genes (E-cadherin, HIC-1, p16) in hydatidiform mole exhibited aberrant methylation whereas none was hypermethylated in normal placenta. There was a significant correlation between methylation and reduced expression of p16, E-cadherin, and TIMP3 (P < 0.001). Fifteen of the 54 patients with hydatidiform mole developed gestational trophoblastic neoplasia requiring chemotherapy. Promoter hypermethylation of p16 alone, or combined with E-cadherin, was significantly correlated to such development (P = 0.001, 0.0005, respectively). Hypermethylation of multiple genes, especially p16, might be related to the subsequent development of gestational trophoblastic neoplasia.

Elevated serum levels of epithelial cell apoptosis-specific cytokeratin 18 neoepitope m30 in critically ill patients

Apoptosis of the epithelium is deemed to play a pivotal role in the pathogenesis of sepsis. A neoepitope in cytokeratin 18 (CK18), termed M30 neoantigen, becomes available at an early caspase cleavage event during apoptosis of epithelium-derived cells and is not detectable in vital or necrotic epithelial cells. A monoclonal antibody, M30, specifically recognizes a fragment of CK18 cleaved at Asp396 (M30 neoantigen). We used an enzyme-linked immunosorbent assay (ELISA) to measure M30 antigen levels in the sera of 15 septic patients. Healthy humans and critical ill patients suffering from severe trauma served as controls. Mann-Whitney U test was used to calculate significance, and a P value of <0.01 was considered to be statistically significant. Serum levels of the CK18 neoepitope M30 were significantly increased in septic patients (236.88 +/- 47.4 U/L) versus trauma (97.2 +/- 17.1 U/L) and healthy controls (66.9 +/- 9.2 U/L) (P < 0.01 and P < 0.008, respectively). The increased serum level of the CK18 neoepitope in septic patients indicates a heightened apoptotic turnover in epithelial cells as compared with trauma patients and healthy controls. Interestingly, nonsurviving trauma patients exhibited a significant increase in the M30 neoantigen as compared with survivors and healthy controls (P < 0.003 and P < 0.002, respectively). The detection of CK18 neoepitope M30 in the serum might be a useful marker in tracing apoptotic epithelium in septic patients.

Differential expression of insulin-like growth factor binding protein 1 and ferritin light polypeptide in gestational trophoblastic neoplasia

BACKGROUND

Hydatidiform mole (HM), the most common type of gestational trophoblastic diseases, can be considered as placenta with abnormal chromosome composition with potential of malignant transformation. Few biologic markers can predict subsequent development of persistent gestational trophoblastic neoplasia (GTN) requiring chemotherapy.

METHODS

Suppression subtractive hybridization (SSH) combined with cDNA microarray was used to compare the differential expression pattern of HM that spontaneously regressed and that subsequently developed metastatic GTN. Tissue-specific chips were constructed from the subtracted cDNA libraries, followed by cDNA microarray analysis. Verification by quantitative RNA analysis by real-time polymerase chain reaction (PCR) and immunohistochemical analysis was performed in 23 genotyped complete HM.

RESULTS

Sixteen differentially expressed transcripts were identified. Quantitative RNA analysis confirmed down-regulation of ferritin light polypeptide (FTL) (P = 0.037) and insulin-like growth factor binding protein 1 (IGFBP1) (P = 0.037) in HM that subsequently developed GTN when compared with those HM that regressed. Immunohistochemical analysis further confirmed reduced IGFBP1 protein (P = 0.03) expression in HM that developed GTN.

CONCLUSIONS

Findings showed that reduced expression of genes related to cell invasion and immunosuppression, especially FTL and IGFBP1, were associated with development of GTN, and this finding may provide a better understanding of the pathogenesis of GTN. The potential application of FTL and IGFBP1 in management of patients with HM should be explored.

Mcl-1 expression in gestational trophoblastic disease correlates with clinical outcome

BACKGROUND

Hydatidiform moles (HMs) are abnormal pregnancies with a propensity for developing persistent disease in the form of gestational trophoblastic neoplasia (GTN), which requires chemotherapy. In previous studies, the authors demonstrated that low apoptotic activity was correlated with the progression of HM to GTN, and they hypothesized that some apoptosis-related genes may determine this progression.

METHODS

The differential expression of apoptotic genes in HMs that subsequently developed into GTN was compared with the same expression in HMs that spontaneously regressed using a human apoptosis array; then, the expression was evaluated with real-time quantitative polymerase chain reaction analysis and immunohistochemistry using 54 clinical samples from patients with HMs who had follow-up data available.

RESULTS

Using an apoptosis array, greater expression of Mcl-1, which is an antiapoptotic gene, was detected in HMs that subsequently developed into GTN. It was confirmed that the levels of Mcl-1 RNA expression (P = 0.017) and Mcl-1 protein expression (P < 0.001) in HMs that developed into persistent disease and required chemotherapy were significantly greater compared with the levels in HMs that regressed. Moreover, Mcl-1 immunoreactivity, which was detected predominantly in cytotrophoblasts, was correlated with the apoptotic index, as assessed with M30 cytoDeath immunohistochemistry, which is a good indicator of apoptotic events in the early-stage disease.

CONCLUSIONS

The current results demonstrated that Mcl-1, as identified by a cyclic DNA array, may play a role in the pathogenesis of HMs and may have potential as a useful marker for predicting the clinical behavior of HMs.

Pathology of gestational trophoblastic diseases

Gestational trophoblastic disease (GTD) is a heterogeneous group of diseases. This used to include partial and complete hydatidiform moles, invasive mole, choriocarcinoma and placental site trophoblastic tumour. In recent years, new entities, including epithelioid trophoblastic tumour, have been added to this family. Non-neoplastic and neoplastic lesions derived from implantation site and chorion intermediate trophoblast have been gaining attention in the literature. New markers for trophoblasts have been identified facilitating histological diagnosis in cases with unusual clinical or pathological features. It is worth noting that histological distinction between hydropic abortion and partial mole and between complete and partial moles, especially at early gestational age, may be difficult. It may not be possible to predict progress of the heterogeneous group of GTD from histopathological features, except probably in placental site trophoblastic tumour. Alternative biological markers may be explored for better patient management.

Expression of Nuclear Factor-Kappa B and Placental Apoptosis in Pregnancies Complicated with Intrauterine Growth Restriction and Preeclampsia: An Immunohistochemical Study

Preeclampsia affects 7-10% of all pregnancies, and is a major cause of maternal and fetal morbidity and mortality. Although enhanced apoptosis is well known in placentas with preeclampsia, the role of transcription factor nuclear factor-kappa B (NF-kappa B) in the process is still being debated. In this work, we investigate the relationship between NF-kappa B expression and trophoblastic cell apoptosis in pregnancies complicated with preeclampsia or intrauterine growth restriction (IUGR) by immunohistochemical analysis of NF-kappa B and three apoptosis related markers: bcl-2, caspase-3, and M30 CytoDeath antibody that identifies early apoptotic changes in the cytoskeleton related to action of caspase. The study was conducted on placental samples from 19 preeclamptic, 5 IUGR-complicated and 10 normal pregnant women. The three conclusions from the statistical analysis of the data are obtained; (i) Significantly higher expression of NF-kappa B in IUGR-complicated (p = 0.003) and preeclamptic placentas (p = 0.004) than the control placentas, (ii) significantly higher M30 index and caspase 3 expression in IUGR and preeclampsia placentas (p = 0.003), and (iii) decreased expression of bcl-2 in IUGR and preeclampsia placentas (p = 0.001). Based on these observations, we suggest that increased trophoblastic apoptosis is at least partially induced by NF-kappa B and reduced bcl-2 expression.

Fas-mediated pathway and apoptosis in normal, hyperplastic, and neoplastic endometrium

OBJECTIVES

Abnormalities in the control of cell proliferation and apoptosis have been suggested to contribute to the development and progression of neoplasia. There are at least two pathways that activate apoptosis. The first is a mitochondria-dependent route governed by bcl-2 family proteins. The second is a parallel mechanism which involves the activation of a group of tumor necrosis factor (TNF) receptors, such as Fas.

METHODS

The aim of this study was to examine the distribution and interrelation between the expression patterns of apoptosis-related proteins such as Fas, caspase-3 (CPP32), and M30, and to investigate the role of Fas-mediated apoptosis in the pathogenesis and progression of endometrial neoplasms.

RESULTS

Using specific antibodies for Fas, caspase-3, and M30, we examined protein expressions in 29 endometrial carcinomas, 30 endometrial hyperplasias, and 21 normal cyclic endometria. The results of immunostaining for Fas and caspase-3 were analyzed semiquantitatively by using an immunohistochemical scoring system (HSCORE) that incorporated both the intensity and the distribution of specific staining. For M30, positive staining cells and extracellular particles were analyzed semiquantitatively per 10 high-power fields.HSCOREs of Fas and caspase-3 were slightly higher in the secretory endometria than in the proliferative endometria. Similarly, M30 reactivity seemed to increase in the late secretory phase of the cycle. HSCOREs of Fas and caspase-3 and the reactivity of M30 were significantly higher in the carcinoma group than in the simple hyperplasia group (P < 0.05). Complex hyperplasias, however, expressed quite similar HSCOREs of Fas and caspase-3 as carcinomas. M30 reactivity was also significantly higher in complex hyperplasias than in simple hyperplasias, and in carcinomas positivity increased significantly (P < 0.05) as the grade progressed.

CONCLUSIONS

The significant increase observed in Fas, caspase-3, and M30 expression in carcinomas as compared with simple hyperplasias may suggest that the Fas-related apoptotic pathway is also involved in the regulation of apoptosis in the endometrial tissue and promotes the development and progression of endometrial neoplasia.

The synthetic retinoid adapalene inhibits proliferation and induces apoptosis in colorectal cancer cells in vitro

Chemotherapy of advanced stages of colorectal carcinoma is unsatisfactory. Retinoids inhibit cell growth and induce apoptosis in a variety of human malignancies. We compared the effect of the synthetic retinoid adapalene (ADA) and 9-cis-retinoic acid (CRA) on carcinoma cell lines in vitro. Colon carcinoma cell lines CC-531, HT-29 and LOVO as well as human foreskin fibroblasts were exposed to different concentrations of ADA and CRA for 3-72 hr. Proliferation was assessed by BrdU incorporation and apoptosis by FACS analysis. Breakdown of DeltaPsi(m) was determined by JC-1 staining and activity of caspases 3 and 8, by a colorimetric assay. Quantitative Western blots were performed to detect changes in bax, bcl-2 and caspase-3. Both retinoic derivatives suppressed DNA synthesis and induced apoptosis in all tested cell lines time- and dose-dependently. While the natural retinoid CRA showed moderate antiproliferative and proapoptotic effects only at the highest concentration (10(-4) M), the synthetic retinoic ADA was significantly more effective, showing remarkable effects even at 10(-5) M. ADA and CRA disrupt DeltaPsi(m) and induce caspase-3 activity in responsive tumor cells. Quantitative Western blots showed a shift of the bax:bcl-2 ratio toward proapoptotic bax in ADA-treated cells. Our results clearly indicate the superiority of ADA compared to CRA. Therefore, we suggest that ADA may be far more suitable as an adjunctive therapeutic agent for treatment of colon cancer in vivo.

Methylation status and expression of E-cadherin and cadherin-11 in gestational trophoblastic diseases

The clinical significance of cadherins in gestational trophoblastic diseases (GTD) is not fully understood. In this study, the expression of E-cadherin and cadherin-11 in 12 normal placentas, 32 cases of hydatidiform mole (HM) including 15 complete HMs and 17 partial HMs, and five choriocarcinomas was investigated by immunohistochemistry and correlated with follow-up of HMs. Cases with available frozen blocks were further analyzed by western blot and semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). Methylation of E-cadherin was investigated by methylation-specific PCR in six normal first trimester placentas, 19 HMs and their associated deciduas. E-cadherin expression was localized to cytotrophoblast and intermediate trophoblast whereas cadherin-11 was expressed in syncytiotrophoblast, intermediate trophoblast, and decidua. Immunoreactivity of E-cadherin was reduced in choriocarcinoma and complete HM when compared with that in normal first trimester placenta (P < 0.01, P = 0.04). Hypermethylation of E-cadherin was demonstrated in three complete HMs with the lowest level of E-cadherin. Compared with normal first trimester placenta, immunoreactivity of cadherin-11 was higher in complete HM (P = 0.02), but lower in choriocarcinoma (P = 0.02). Such differential expression was confirmed by western blot and semiquantitative RT-PCR. No obvious association was observed between the development of persistent trophoblastic disease with the expression of E-cadherin and cadherin-11.

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.