Serum cytokines in gestational trophoblastic diseases

Progress of immunotherapies in gestational trophoblastic neoplasms

BACKGROUND

Different from other malignant gynecologic tumors, gestational trophoblastic neoplasms (GTNs) exhibit an exceptionally high cure rate primarily through chemotherapeutic interventions. However, there exists a small subset of refractory GTNs that do not respond to conventional chemotherapies. In such cases, the emergence of immunotherapies has demonstrated significant benefits in managing various challenging GTNs.

PURPOSE

This article aims to provide a comprehensive and systematic review of the immune microenvironment and immunotherapeutic approaches for GTNs. The purpose is to identify potential biomarkers that could enhance disease management and summarize the available immunotherapies for ease of reference.

METHODS

We reviewed the relevant literatures toward immunotherapies of GTNs from PubMed.

CONCLUSION

Current immunotherapeutic strategies for GTNs mainly revolve around immune checkpoint inhibitors (ICIs) targeting programmed death receptor 1 (PD-1) and programmed cell death ligand 1 (PD-L1). Prominent examples include avelumab, pembrolizumab, and camrelizumab. However, existing researches into the underlying mechanisms are still limited.

A possible association between hydatidiform mole and the COVID-19 pandemic: A retrospective cohort study

Objective

To confirm an increase in the number of women with molar pregnancy during the COVID-19 pandemic.

Methods

In this retrospective cohort study, all patients with complete or partial mole diagnosed at our institution between January 1, 2010 and October 31, 2020, were included. To verify whether there was an increase in the incidence of hydatidiform mole (HM) and deliveries in 2020, the incidences for each year from January 2010 to October 2020 were recorded. In addition, we identified all women who were diagnosed with HM from January to October 2020, and compared them with a control group who underwent uterine evacuation for missed abortion of a singleton pregnancy during the same period. We also documented the time taken to diagnose missed abortion or molar pregnancy to check if a delay in diagnosis can explain the increase in HM incidence.

Results

Between 2016 and 2019, there was a statistically significant increase in the incidence of molar pregnancy. A further increase occurred in 2020 (odds ratio = 2.071). The mean gestational age of the embryo at the time of diagnosis was smaller in the HM group than in the missed abortion group (6.3 ± 1.67–7.4 ± 2.4, one-sided P = 0.034), meaning that it took more time (days) to diagnose molar pregnancy than missed abortion (22.38 ± 10.32 vs. 15.83 ± 7.83 days, P = 0.012).

Conclusion

There was a significant increase in the incidence of molar pregnancy during the COVID-19 pandemic, possibly because of the delay in receiving medical care. We recommend providing gynecological primary care services during a crisis, such as a pandemic.

COVID-19 and hydatidiform mole

The emergence of coronavirus disease 2019 (COVID‐19) as a pandemic threatens the entire world resulting in severe consequences for people's health. Pregnant patients with COVID‐19 had immune dysregulation that could result in abnormal pregnancy outcomes such as hydatidiform mole (HM), recurrent pregnancy loss, and early‐onset preeclampsia. In this article, we tried to summarize the possible association between COVID‐19 and the HM's development by reviewing the role of NOD‐Like Receptor (NLR) Family Pyrin Domain Containing 7 (NLRP7), cytokines, zinc, and leukocytes in the pathogenesis of HM.

Hydatidiform mole in the era of COVID-19 pandemic. Is there an association?

Coronavirus disease 2019 (COVID‐19) is considered a worldwide pandemic. COVID‐19 patients had profound immune dysregulation so they could be susceptible for adverse pregnancy outcomes as hydatidiform mole. In this article, we tried to explain the link between hydatidiform mole and COVID‐19.

Thiol/Disulfide Homeostasis in Patients with Molar Pregnancies

Introduction: We aimed to investigate serum dynamic thiol and disulfide levels in patients with molar pregnancy (MP), and compare these concentrations with those of healthy pregnant women. Materials and Methods: Forty-one patients who were diagnosed with MP and 41 gestational age-matched healthy pregnant women were included in this prospective study. MP cases were separated in two groups as complete hydatidiform mole (CHM) and partial hydatidiform mole (PHM). Demographic features and thiol/disulfide homeostasis were recorded for each woman. Results: There was a significant correlation between the decrease in the total thiol and native thiol levels in MP patients. However, no significant difference was observed between CHM and PHM groups in terms of serum disulfide levels. Conclusion: OS is increased in MPs both in complete and partial moles, as determined by thiol/disulfide analysis.

Increased LIGHT leading to sFlt-1 elevation underlies the pathogenic link between hydatidiform mole and preeclampsia

Hydatidiform moles are known to pose an extremely high risk of severe early-onset preeclampsia if left untreated. TNF superfamily cytokine, LIGHT has recently been reported to contribute to pathophysiology of preeclampsia. The present study aimed to investigate the involvement of LIGHT in hydatidiform moles. We measured the serum levels of LIGHT and sFlt-1 by ELISA in 17 women with complete hydatidiform mole (HM) and 20 gestational-age-matched normal pregnant women (control). As a result, the serum LIGHT levels were significantly higher in HM as compared with those in control (69.9 ± 9.6 pg/ml vs 25.4 ± 5.3 pg/ml, p = 0.0001) and the serum levels of LIGHT were significantly positively correlated with those of sFlt-1 in HM (r = 0.68, p = 0.0029). Immunohistochemical analysis revealed that the expression levels of LIGHT were increased in HM placentas as compared with controls, and LIGHT and sFlt-1 were co-localized in the trophoblast cells of HM. In vitro studies using primary syncytiotrophoblast cells demonstrated that LIGHT directly induced sFlt-1 expression in trophoblast cells. Our results indicated that elevated LIGHT in the trophoblast cells of hydatidiform mole induces sFlt-1, which might underlie the pathogenic mechanism of early-onset preeclampsia developing secondary to molar pregnancies.

Tumor necrosis factor-α regulates angiogenesis of BeWo cells via synergy of PlGF/VEGFR1 and VEGF-A/VEGFR2 axes

OBJECTIVES

Tumor necrosis factor-alpha (TNF- α) promotes tumor growth by enhancing tumor angiogenesis; however, the effects on choriocarcinoma remain unknown. We investigated the effects of TNF-α on the production of placental growth factor (PlGF) and vascular endothelial growth factor-A (VEGF-A) in BeWo cells and also examined its significance on the interactions with the endothelial cells by using human umbilical vein endothelial cells (HUVECs).

MATERIALS & METHODS

After incubation with TNF-α (10-10⁵ pg/mL), the expression of PlGF and VEGF-A in BeWo cells were assessed by ELISA and RT-PCR. HUVEC tube formation assays were conducted to assess the angiogenic activity of the conditioned medium. The phosphorylation status of VEGFR1 and VEGFR2 in HUVECs under the stimulation of the conditioned medium was assessed by immunoprecipitation and immunoblotting. The same experiments were repeated with recombinant PlGF and VEGF-A to confirm the effects of the growth factors.

RESULTS

Low levels (10-10² pg/mL) of TNF-α enhanced the mRNA and protein levels of PlGF, but the changes in VEGF-A levels were not significant. HUVEC tube formation was promoted by the conditioned medium, and those effects were inhibited by the anti-VEGFR1 antibody and PlGF-siRNA. VEGFR2 was significantly phosphorylated by the conditioned medium, while the effect on VEGFR1 phosphorylation was very weak. HUVEC tube formation was incomplete when recombinant PlGF was used; however, the addition of PlGF promoted the effects of VEGF-A. The addition of PlGF along with VEGF-A also stimulated VEGFR2 phosphorylation.

CONCLUSIONS

TNF-α promoted PlGF synthesis in BeWo cells and regulated angiogenesis via synergy of the PlGF/VEGFR1 and VEGF-A/VEGFR2 axes.

The role of shed placental DNA in the systemic inflammatory syndrome of preeclampsia

Preeclampsia is a syndrome occurring only in pregnancy characterized by systemic maternal inflammation and associated with the presence of the placenta. How these 2 aspects of the disease are linked has been the subject of numerous theories and ideas. Recently, there has been increasing interest in DNA shed from the placenta into the maternal circulation as a potential agent initiating the inflammatory response. This review will discuss the current evidence and future directions for placental DNA as the linking factor in preeclampsia in the context of other hypotheses.

Increased insulin resistance and C-reactive protein in women with complete hydatidiform mole

OBJECTIVE

To evaluate (i) insulin resistance and C-reactive protein (CRP) levels in women with complete hydatidiform mole (CHM) and (ii) whether there were any correlations between these parameters and CHM.

METHODS

Thirty-two women with CHM and 30 healthy pregnant women were enrolled in the study. Fasting serum glucose and insulin levels, low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol (TC), and triglyceride (TG) and C-reactive protein (CRP) were measured. Insulin resistance was calculated by the homeostasis model assessment ratio (HOMA-IR).

RESULTS

Fasting glucose, insulin, HOMA-IR, CRP, and TG levels were higher, and HDL was lower among patients with CHM compared with healthy pregnant group (p < 0.05 for all). There were positive associations between CHM status and glucose, insulin, HOMA-IR, CRP, TG levels and had a negative correlation with HDL (p < 0.05 for all). The receiver operating characteristic curve (ROC) analysis value for HOMA-IR in CHM was 0.96 (95% confidence interval (CI) = 0.92-1.00), sensitivity = 94%, and specificity = 87%. The area under ROC curve value for CRP was 0.72 (95% confidence interval (CI) = 0.58-0.84), sensitivity = 82%, and specificity = 60% in CHM.

CONCLUSIONS

Insulin resistance and CRP were found to be higher among patients with CHM. These parameters were also closely associated with CHM. Further studies are needed to investigate the nature of this link in this group.

Redox considerations in female reproductive function and assisted reproduction: from molecular mechanisms to health implications

Physiological levels of reactive oxygen species (ROS) play an important regulatory role through various signaling transduction pathways in folliculogenesis, oocyte maturation, endometrial cycle, luteolysis, implantation, embryogenesis, and pregnancy. Persistent and elevated generation of ROS leads to a disturbance of redox potential that in turn causes oxidative stress (OS). Our literature review captures the role of ROS in modulating a range of physiological functions and pathological processes affecting the female reproductive life span and even thereafter (i.e., menopause). The role of OS in female reproduction is becoming increasingly important, as recent evidence suggest that it plays a part in conditions such as polycystic ovarian disease, endometriosis, spontaneous abortions, preeclampsia, hydatidiform mole, embryopathies, preterm labor, and intrauterine growth retardation. OS has been implicated in different reproductive scenarios and is detrimental to both natural and assisted fertility. Many extrinsic and intrinsic conditions exist in assisted reproduction settings that can be tailored to reduce the toxic effects of ROS. Laboratory personnel should avoid procedures that are known to be deleterious, especially when safer procedures that can prevent OS are available. Although antioxidants such as folate, zinc, and thiols may help enhance fertility, the available data are contentious and must be evaluated in controlled studies with larger populations.

The role of oxidative stress in spontaneous abortion and recurrent pregnancy loss: a systematic review

Human reproduction is not considered a highly efficient biological process. Before the end of the first trimester, 30%-50% of conceptions end in spontaneous abortion. Most losses occur at the time of implantation. 15%-20% of clinical pregnancies end in spontaneous abortions. Recurrent pregnancy loss is a frustrating clinical problem both for clinicians and patients. Recurrent pregnancy loss affects 0.5%-3% of women in the reproductive age group, and between 50%-60% of recurrent pregnancy losses are idiopathic. Oxidative stress-induced damage has been hypothesized to play a role in spontaneous abortion, idiopathic recurrent pregnancy loss, hydatidiform mole, defective embryogenesis, and drug-induced teratogenicity. Some studies implicate systemic and placental oxidative stress in the pathophysiology of abortion and recurrent pregnancy loss. Oxidant-induced endothelial damage, impaired placental vascularization and immune malfunction have all been proposed to play a role in the pathophysiology of idiopathic recurrent pregnancy loss. Oxidative stress-induced placental dysfunction may be a common cause of the multifactorial and polygenic etiologies of abortion, recurrent pregnancy loss, defective embryogenesis, hydatidiform mole, and drug-induced teratogenic effects. Oxidative stress-induced modification of phospholipids has been linked to the formation of antiphospholipid antibodies in the antiphospholipid syndrome. The objective of this review was to examine the association between oxidative stress, spontaneous abortion and recurrent pregnancy loss, based on the published literature. We conducted an extensive literature search utilizing the databases of Medline, CINAHL, and Cochrane from 1986 to 2005. The following keywords were used: oxidative stress, abortion, recurrent pregnancy loss, reactive oxygen species, antioxidants, fetal development, and embryopathies. We conducted an electronic search, as well as a manual search of cross-references. We have included all studies in the English language found in the literature focusing on oxidative stress and its association with abortions, recurrent pregnancy loss and drug-induced teratogenicity. The role of antioxidant vitamins for primary prevention of oxidative stress-induced pathologies needs to be investigated further.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to state that the causes of spontaneous and recurrent abortion are multifaceted, however, some of the causes may be preventable and also explain that the role of oxidative stress during pregnancy and adverse pregnancy outcomes has a basis in pathophysiology, although the role of oxidative stress and the treatment of oxidative stress during or before pregnancy remains speculative.

Immunobiology of gestational trophoblastic diseases

Gestational trophoblastic diseases (GTDs) comprise a group of interrelated diseases characterized by development after gestation, widespread metastases, and high curability with chemotherapy. The good prognosis of GTDs is considered partly a result of the host immune response to paternal antigens expressed on trophoblastic cells. In this study, we review current understanding of the immunobiology of GTDs. First of all, we describe the microenvironment between trophoblastic cells and subpopulation of immune cells. Second, immunogenetics, immune microenvironment around abnormal trophoblast, and mechanism of GTDs escaping from maternal immune system surveillance were also discussed. Third, we propose the possible immunotherapy for persistent GTDs, particularly the vaccine designed on human chorionic gonadotrophin, which is generally accepted as a tumor marker for GTDs diagnosis. Due to the low incidence of GTDs and high response to chemotherapy, there have been few literatures about immunobiologic characteristics of GTDs compared with the other gynecologic malignancies, such as ovarian cancer, but the immunologic behavior of GTDs should be explored for further understanding of the etiology of these diseases and to help designing immunotherapeutic strategies for persistent GTDs.

Angiogenesis in gynecological oncology-mechanism of tumor progression and therapeutic targets

The purpose of this article is to review the current literature pertaining to various angiogenic stimulators and angiogenesis inhibitors in gynecological malignancies and the relevance of these markers in the prognosis of these diseases. We also summarize the antiangiogenic drugs currently in development and in clinical use in gynecological oncology. The information was obtained from a computer search of MEDLINE for studies published in the English language regarding angiogenesis and angiogenesis inhibitors in gynecological malignancies between 1970 and December 2003; additional sources were identified through cross-referencing. In ovarian cancer, various different angiogenic activators have been found to correlate with microvessed density (MVD), stage, lymph node and peritoneal metastasis, and survival. In cervical cancer, correlation has been seen between increased angiogenic markers and stage, grade, tumor size, and survival. Studies in endometriat cancer show correlation of angiogenic markers with stage, grade, MVD, and survival. Whereas, in gestational trophoblastic neoplasm (GTD) only few markers have been studied, and some correlated with progression. Information on anti angiogenic drugs currently in ongoing and upcoming trials in gynecological malignancies is also presented. Angiogenesis factors may have a prognostic role to play in patients with gynecological cancers and should continue to be investigated as clinically useful tumor markers. Antiangiogenic-targeted therapies offer an attractive strategy for clinical investigation in gynecologic oncology.

Secretion of tumor necrosis factor-alpha from human placental tissues induced by hypoxia-reoxygenation causes endothelial cell activation in vitro: a potential mediator of the inflammatory response in preeclampsia

Preeclampsia is a hypertensive complication of human pregnancy characterized by generalized maternal endothelial cell activation. Circulating pro-inflammatory cytokines derived from the placenta are thought to play a key role. We recently demonstrated that hypoxia-reoxygenation (H/R) of placental tissues in vitro causes equivalent oxidative stress to that seen in preeclampsia. Our aim was to determine whether H/R also increases production of tumor necrosis factor-alpha (TNF-alpha), and whether conditioned media from samples exposed to H/R causes activation of human umbilical vein endothelial cells (HUVECs). Concentrations of mRNA encoding TNF-alpha were significantly higher in placental tissues subjected to H/R compared to hypoxic or normoxic controls. Although there was no difference in the concentrations of TNF-alpha protein in tissue homogenates, levels of TNF-alpha protein in the medium were significantly higher after H/R compared to controls, indicating increased secretion. Furthermore, conditioned medium from samples subjected to H/R caused increased expression of E-selectin by HUVECs, and the addition of anti-TNF-alpha antibodies significantly reduced that activation. These results are consistent with our hypothesis that intermittent perfusion of the placenta, secondary to reduced trophoblast invasion, causes increased secretion of TNF-alpha, and that this contributes to the activation of maternal endothelial cells that characterizes preeclampsia.

Angiogenin and gestational trophoblastic tumors, a promising prognostic marker

The aim of this study was to evaluate the diagnostic and prognostic values of serum angiogenin concentration in cases with gestational trophoblastic diseases (GTDs). Seventy-two patients with GTDs and 20 first trimester healthy pregnant women (controls) participated in this study. According to the WHO scoring system, GTDs were subgrouped into 24 hydatiform mole spontaneous regression (HMSR), 18 postmolar gestational trophoblastic tumors of high risk (PMHR), 16 low-risk choriocarcinoma, and 14 high-risk choriocarcinoma. Before treatment, a blood sample from each case was assayed for human chorionic gonadotrophin , subunit (hCGb) by radioimmunoassay and angiogenin by enzyme immunoassay. Follow-up hCGb and angiogenin assays were carried out for 1 year after treatment. Pretreatment of abnormal values of serum angiogenin (> 711 ng/ml, upper 95% confidence interval of controls) was encountered in 100% of PMHR cases compared to no single case of HMSR. Serum angiogenin levels in low- and high-risk cases with choriocarcinoma were significantly higher than in controls. Abnormal high values were encountered in 25% and 86% of cases, respectively. None of the low-risk cases exceeded 920 ng/ml, while 72% of high-risk cases exceeded this value. Serial angiogenin assays were correlated with disease progression and were positively correlated with serum hCGb (r = 0.75, p < 0.01). In conclusion, serum angiogenin may be a valuable marker of differential diagnosis of GTDs and its serial measurements are suggestive of remission and effective therapeutic intervention or disease progression.

Cytokines of the placenta and extra-placental membranes: biosynthesis, secretion and roles in establishment of pregnancy in women

Virtually all known cytokines have been demonstrated to be expressed in the placenta and associated fetal and maternal membranes during normal gestation. In addition to playing their traditional roles as modulators of immunological function, cytokines derived from the placenta and extraplacental membranes, together with other locally-derived growth factors, appear to be implicated in various aspects of implantation and placental development. Imbalances in the intrauterine cytokine milieu around the time of implantation and invasion may play a causative role in disorders associated with early pregnancy failure, and are also associated with the abnormal trophoblast development seen in gestational trophoblastic disease. Cytokines thus appear to be an important component of a paracrine/autocrine communication network operating within the feto-maternal interface to ensure the successful establishment of pregnancy.

Production of interleukin (IL)-6 and IL-8 by a choriocarcinoma cell line, BeWo

To clarify the biological and pathological features of choriocarcinoma, we evaluated the in vitro production of cytokines by a choriocarcinoma cell line, BeWo. We measured the concentration of interleukin (IL)-6 and IL-8 in the culture media of BeWo cells after stimulation with various modulatory agents of cytokine expression by enzyme-linked immunosorbent assays. Northern blot analysis was used to examine the expression of IL-6 and IL-8 mRNA in these cells. A weak expression of IL-6 and IL-8 was detected in unstimulated BeWo cells by both methods. IL-6 transcription and secretion were dose-dependently enhanced by stimulation with IL-1beta, tumour necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta1 and 12-O-tetradecanoyl phorbol-13-acetate (TPA). Forskolin, lipopolysaccharide and interferon-gamma had no effect on these cytokines production. The TNF-alpha-induced secretion of IL-6 was inhibited by dexamethasone. The TPA-induced production of IL-6 was inhibited by 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine and sphyngosine, suggesting the involvement of a protein kinase C-dependent pathway. Levels of IL-8 mRNA and protein were also dose-dependently increased by stimulation with IL-1beta, TNF-alpha and TPA. In contrast to IL-6, the expression of IL-8 was not affected by TGF-beta1. It is suggested that, in addition to the production of steroidal and non-steroidal hormones, these cytokines may serve as part of a cytokine network that modulates the proliferation and angiogenesis of choriocarcinomas.

Placental cytokines and the pathogenesis of preeclampsia

The authors explore the hypothesis that tumor necrosis factor-alpha (TNF-alpha) and possibly other inflammatory cytokines are overproduced by the placenta in response to local ischemia/hypoxia contributing to increased plasma levels, and subsequent endothelial activation and dysfunction in the pregnancy disorder, preeclampsia. It is widely held that inadequate trophoblast invasion and physiologic remodeling of spiral arteries initiate placental ischemia/hypoxia in preeclampsia. Furthermore, focal areas of placental hypoxia have been implicated in the production of "toxic" factor(s) by the placenta, which circulate and cause maternal disease. Placental trophoblast cells and fetoplacental macrophages normally produce TNF-alpha and interleukin-1 (IL-1), which are capable of producing endothelial cell activation and dysfunction. Hypoxia has recently been reported to increase TNF-alpha and IL-1 production by term villous explants from the human placenta. Placental cells also express erythropoietin (EPO), which is the prototype molecule for transcriptional regulation by hypoxia in mammals. Interestingly, TNF-alpha and IL-1 have DNA sequence homologous or nearly homologous to the hypoxia-responsive enhancer element of the EPO gene, thus providing a potential, but as of yet, untested molecular link between placental hypoxia and stimulation of cytokine production. Inflammatory cytokines overproduced by the placenta in response to hypoxia may then lead to increased plasma levels and endothelial activation and dysfunction in preeclampsia. The purpose of this short review is to critically evaluate the hypothesis that placental cytokines contribute to the pathogenesis of preeclampsia. Of note, the etiology of the disease presumably related to deficient trophoblast invasion is beyond the scope of this work.