Involvement of Membrane GRP78 in Trophoblastic Cell Fusion

Fradet, Sarah; Pierredon, Sandra; Ribaux, Pascale; Epiney, Manuella; Shin‐ya, Kazuo; Irion, Olivier; Cohen, Marie

doi:10.1371/journal.pone.0040596

Cited by 32 publications

(39 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Based on the HCQ concentration used in the literature and its effects on BeWo cell viability (Figure S1), we decided to treat cells at 0.5 μg mL −1 HCQ for 48 h. At this concentration, HCQ completely reversed the effect of the APS patient's plasma (Fig. A).…”

Section: Resultsmentioning

confidence: 99%

Hydroxychloroquine restores trophoblast fusion affected by antiphospholipid antibodies

Marchetti

Ruffatti

Wuillemin

et al. 2014

Journal of Thrombosis and Haemostasis

View full text Add to dashboard Cite

Summary. Background: Obstetric antiphospholipid syndrome (APS) is defined by pregnancy complications associated with antiphospholipid antibodies (aPL). The mechanisms of the pathogenic effects of aPL in pregnancy are poorly understood. Toll-like receptors (TLR) have been implicated previously in APS. Objectives: The aims of our study were (1) to determine aPL effects on trophoblastic cell fusion and differentiation, (2) to identify which TLR is involved in this process, and (3) to evaluate the efficacy of hydroxychloroquine (HCQ) to counteract the effects of aPL. Methods: BeWo cells are a model for trophoblast fusion and differentiation. Fusion index was assessed by immunocytochemical examination, and biochemical differentiation by using ELISA-measured b-human choronic gonadotropin hormone (b-hCG) secretion. We used three types of aPL to study their effect on cell fusion and differentiation: aPL derived from obstetric APS patients and affinity purified and polyclonal rabbit anti-b2-glycoprotein-1 (anti-b2GP1) antibodies. Experiments on fusion were confirmed using primary cytotrophoblastic cells. Results: All of the types of aPL used decreased the fusion index in BeWo and primary trophoblastic cells (64%, 52%, and 41% for BeWo cells and 67% and 62% for primary cells, respectively), and anti-b2GP1 antibodies decreased hCG secretion in BeWo cells (41%). To block TLR4 antibodies or to abolish TLR4 cell surface expression restored fusion index in both cell types and b-human choronic gonadotropin hormone excretion in BeWo cells. HCQ treatment induced the same effect and decreased TLR4 mRNA (40% and 35%, respectively) and protein expressions (62% and 42%, respectively) in BeWo cells. Conclusion: Anti-b2GP1 antibodies decrease trophoblastic differentiation via TLR4. This effect is restored by HCQ, suggesting its therapeutic interest in APS pregnancies.

show abstract

Section: Resultsmentioning

confidence: 99%

Hydroxychloroquine restores trophoblast fusion affected by antiphospholipid antibodies

Marchetti

Ruffatti

Wuillemin

et al. 2014

Journal of Thrombosis and Haemostasis

View full text Add to dashboard Cite

show abstract

“…BeWo cells fuse in response to FSK-induced cAMP level and have been extensively employed as an in vitro model for studying various placental trophoblast functions (Wice et al, 1990;Fradet et al, 2012). KLF6 protein was already expressed in untreated cells (0 h) and was rapidly up-regulated by FSK treatment after 2 h, decreasing near to basal levels after 48 h (Fig.…”

Section: Klf6 Is Expressed In Bewo Cells and Its Down-regulation Redumentioning

confidence: 99%

A novel regulator of human villous trophoblast fusion: the Krüppel-like factor 6

Racca

Ridano

Camolotto

et al. 2014

MHR: Basic Science of Reproductive Medicine

View full text Add to dashboard Cite

Cell-cell fusion is an essential event during life. Throughout human pregnancy, the syncytiotrophoblast (STB) layer of the placenta is formed by continuous fusion of the underlying villous cytotrophoblasts, thus maintaining placental functionality. Defects in this process are associated with pathologies like pre-eclampsia and intrauterine growth restriction. Krüppel-like factor 6 (KLF6) is a transcription factor highly expressed in human and murine placenta. However, KLF6 functions in trophoblast cells remain largely unexplored. The aim of this work was to address the role of KLF6 during STB formation. KLF6 knockdown through small interfering RNA experiments hindered cell-cell fusion revealed by immunofluorescence microscopy in human primary villous cytotrophoblast as well as in the human placental-derived BeWo cell line. Furthermore, KLF6 silencing led to a decrease in the expression of the fusogenic protein Syncytin-1 and the cell cycle regulator p21 measured by quantitative RT-PCR and western blot assays. On the contrary, transcript levels of genes that encode for proteins involved in STB formation such as Syncytin-1, Syncytin-2, Connexin-43 and Zonula Occludens-1 increased when KLF6 was overexpressed in differentiating villous cytotrophoblasts and in non-fusing placental-derived JEG-3 cells. Interestingly, the expression of two trophoblast biochemical differentiation markers, bhCG and PSG3, were not reduced after KLF6 silencing in differentiating trophoblast cells. Present results support the notion that KLF6 is a relevant participant in cytotrophoblast fusion.

show abstract

“…The hypoxic conditions, which are known to exist in the tumor environment, are capable of eliciting the UPR. Interestingly, we have shown that GRP78, master regulator of the UPR, is involved in physiological cell fusion leading to formation of syncytiotrophoblast [22]. In order to test the UPR involvement in ovarian cancer cell fusion, we treated SKOV3 and COV318 cells with ERS inducers.…”

Section: -Ers Increases Cancer Cell Fusionmentioning

confidence: 99%

“…In ovarian cancer cells, GRP78 was shown to be overexpressed [21], suggesting UPR activation in these cells. Interestingly, GRP78 plays also an important role in trophoblastic cell fusion [22,23]. We thus hypothesized that UPR activation could be involved as well in EOC cell fusion and hence the occurrence of PGCCs.In this article, we confirmed Zhang et al results stating that PGCCs derive at least partially from cell fusion in SKOV3 cells [9].…”

mentioning

confidence: 99%

Linking endoplasmic reticulum stress to polyploidy in ovarian cancer cells

Yart

Bastida-Ruiz

Wuillemin

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

Polyploid giant cancer cells (PGCCs) have been observed in epithelial ovarian tumors and have the ability to survive to antimitotic drugs. Their appearance can result from paclitaxel treatment or hypoxia, two conditions known to induce unfolded protein response (UPR) activation. PGCCs produced under hypoxia may be formed by cell fusion and can contribute by bursting and budding to the generation of cancer stem-like cells which have a more aggressive phenotype than the parental cells. Despite the fact that PGCCs may contribute to tumor maintenance and recurrence, they were poorly studied. Here, we confirmed that PGCCs could derive, at least in part, from cell fusion. We also observed that PGCCs nuclei were able to fuse. The resulting cells were able to proliferate by mitosis and were more invasive than the parental cancer cells. Using two different ovarian cancer cell lines (COV318 and SKOV3), we showed that UPR activation with chemical inducers increased cell fusion and PGCCs appearance. Down-regulation of the UPR-associated protein PERK expression partially reversed the UPR-induced PGCCs formation, suggesting that the PERK arm of the UPR is involved in ovarian PGCCs onset. Keywords: ER stress; unfolded protein response; ovarian cancer; PGCC; cell fusion; nuclei fusion; invasion large cells containing several copies of DNA and positive for cancer stem cell markers [10]. Interestingly, the presence of PGCCs in ovarian cancer has been reported preferentially at late disease stages and in high pathological grades [10]. We previously showed that primary EOC cells isolated from malignant ascites were able to spontaneously form PGCCs in culture [11]. However, the origin of PGCCs is controversial since both fusion or endoreplication processes could give rise to them [8,9,12]. Zhang et al., demonstrated that in SKOV3, an EOC cell line established from ascites, the formation of PGCCs was at least partially due to cell fusion events [9]. In the study conducted by Zhang et al., the PGCCs derived from EOC cells had striking properties such as different cell cycle regulation and division profile, changing their daughter generation mechanism from mitosis to budding, which confer these cells the resistance to cytotoxic chemotherapy treatments [9]. Additionally, it was found that hypoxia increased PGCCs formation [9,[13][14][15], but other conditions such as chemotherapy could also favor their production [13].The tumor environment is known to be hypoxic and hypoglycemic due to the low irrigation caused by the fast and erroneous angiogenesis that tumor mass undergo [reviewed at [16]]. These conditions are capable of triggering the endoplasmic reticulum stress (ERS) response or unfolded protein response (UPR) which is essential for cellular adaptation to stressful situations [17]. In homeostatic conditions, the three UPR-associated proteins, protein kinase RNA-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1α (IRE1α) and activating transcription factor 6 (ATF6), remain inactive because of their binding with Gl...

show abstract

Involvement of Membrane GRP78 in Trophoblastic Cell Fusion

Cited by 32 publications

References 35 publications

Hydroxychloroquine restores trophoblast fusion affected by antiphospholipid antibodies

Hydroxychloroquine restores trophoblast fusion affected by antiphospholipid antibodies

A novel regulator of human villous trophoblast fusion: the Krüppel-like factor 6

Linking endoplasmic reticulum stress to polyploidy in ovarian cancer cells

Contact Info

Product

Resources

About