Di-ethylhexylphthalate (DEHP) modulates cell invasion, migration and anchorage independent growth through targeting S100P in LN-229 glioblastoma cells

Di-(2-ethylhexyl) phthalate aggravates psoriasis-like skin lesions: In vitro and in vivo evaluation

Di-(2-ethylhexyl) phthalate (DEHP), which is a widely used phthalate (PAE), has recently received public attention owing to it causing health problems. The aim of this study was to elucidate the aggravating effects of DEHP on psoriasis and skin toxicity. Human keratinocyte (HaCaT) cells were treated with gradient concentrations of DEHP, and mice with imiquimod (IMQ)-induced psoriasiform dermatitis were hypodermically injected with 40 μg/kg/day of DEHP for seven consecutive days. The skin condition was assessed based on the psoriasis area and severity index score, which indicated the deterioration of IMQ-induced psoriasis-like skin lesions after DEHP exposure. To further analyze the effect of DEHP on psoriasis, the proliferation, inflammation, and tight junction (TJ) damage were examined, which correlated with the development and severity of psoriasis. The results showed that DEHP promoted proliferation both in vivo and in vitro, which manifested as epidermal thickening; an increase in cell viability; upregulation of Ki67, CDK2, cyclinD1, and proliferating cell nuclear antigen; and downregulation of p21. An excessive inflammatory response is an important factor that exacerbates psoriasis, and our results showed that DEHP can trigger the release of inflammatory cytokines as well as the infiltration of T cells. TJ disorders were found in mice and cells after DEHP treatment. Additionally, p38 mitogen-activated protein kinase (MAPK) was strongly activated during this process, which may have contributed to skin toxicity caused by DEHP. In conclusion, DEHP treatment promotes proliferation, inflammation, TJ disruption, and p38 MAPK activation in HaCaT cells and psoriasis-like skin lesions.

Di-(2-ethylhexyl) phthalate exposure impairs cortical development in hESC-derived cerebral organoids

Di-(2-ethylhexyl) phthalate (DEHP), a ubiquitous environmental endocrine disruptor, is widely used in consumer products. Increasing evidence implies that DEHP influences the early development of the human brain. However, it lacks a suitable model to evaluate the neurotoxicity of DEHP. Using an established human cerebral organoid model, which reproduces the morphogenesis of the human cerebral cortex at the early stage, we demonstrated that DEHP exposure markedly suppressed cell proliferation and increased apoptosis, thus impairing the morphogenesis of the human cerebral cortex. It showed that DEHP exposure disrupted neurogenesis and neural progenitor migration, confirmed by scratch assay and cell migration assay in vitro. These effects might result from DEHP-induced dysplasia of the radial glia cells (RGs), the fibers of which provide the scaffolds for cell migration. RNA sequencing (RNA-seq) analysis of human cerebral organoids showed that DEHP-induced disorder in cell-extracellular matrix (ECM) interactions might play a pivotal role in the neurogenesis of human cerebral organoids. The present study provides direct evidence of the neurodevelopmental toxicity of DEHP after prenatal exposure.

The Role of the S100 Protein Family in Glioma

The S100 protein family consists of 25 members and share a common structure defined in part by the Ca²⁺ binding EF-hand motif. Multiple members' dysregulated expression is associated with progression, diagnosis and prognosis in a broad range of diseases, especially in tumors. They could exert wide range of functions both in intracellular and extracellular, including cell proliferation, cell differentiation, cell motility, enzyme activities, immune responses, cytoskeleton dynamics, Ca²⁺ homeostasis and angiogenesis. Gliomas are the most prevalent primary tumors of the brain and spinal cord with multiple subtypes that are diagnosed and classified based on histopathology. Up to now the role of several S100 proteins in gliomas have been explored. S100A8, S100A9 and S100B were highly expression in serum and may present as a marker correlated with survival and prognosis of glioma patients. Individual member was confirmed as a new regulator of glioma stem cells (GSCs) and a mediator of mesenchymal transition in glioblastoma (GBM). Additionally, several members up- or downregulation have been reported to involve in the development of glioma by interacting with signaling pathways and target proteins. Here we detail S100 proteins that are associated with glioma, and discuss their potential effects on progression, diagnosis and prognosis.

p53 as a unique target of action of cisplatin in acute leukaemia cells

Acute promyelocytic leukaemia (APL) occurs in approximately 10% of acute myeloid leukaemia patients. Arsenic trioxide (ATO) has been for APL chemotherapy, but recently several ATO-resistant cases have been reported worldwide. Cisplatin (CDDP) enhances the toxicity of ATO in ovarian, lung cancer, chronic myelogenous leukaemia, and HL-60 cells. Hence, the goal of this study was to investigate a novel target of CDDP action in APL cells, as an alternate option for the treatment of ATO-resistant APL patients. We applied biochemical, molecular, confocal microscopy and advanced gene editing (CRISPR-Cas9) techniques to elucidate the novel target of CDDP action and its functional mechanism in APL cells. Our main findings revealed that CDDP activated p53 in APL cells through stress signals catalysed by ATM and ATR protein kinases, CHK1 and CHK2 phosphorylation at Ser 345 and Thr68 residues, and downregulation and dissociation of MDM2-DAXX-HAUSP complex. Our functional studies confirmed that CDDP-induced repression of MDM2-DAXX-HAUSP complex was significantly reversed in both nutilin-3-treated KG1a and p53-knockdown NB4 cells. Our findings also showed that CDDP stimulated an increased number of promyelocytes with dense granules, activated p53 expression, and downregulated MDM2 in liver and bone marrow of APL mice. Principal conclusion of our study highlights a novel mode of action of CDDP targeting p53 expression which may provide a basis for designing new anti-leukaemic compounds for treatment of APL patients.

Arsenic trioxide reduces the expression of E2F1, cyclin E, and phosphorylation of PI3K signaling molecules in acute leukemia cells

Arsenic trioxide (ATO) has been used for the treatment of acute promyelocytic leukemia (APL). Although ATO modulates cell cycle progression and apoptosis in APL cells, its exact mechanism of action remains elusive. In this research, we investigated its effects on E2F1, cyclin E, p53, pRb, and PI3K signaling molecules by western blotting, immunocytochemistry and/or confocal imaging. We found that ATO inhibited the proliferation of APL cells through down-regulation of E2F1 and cyclin E expression, and stimulation of pRb. It also reduced the interaction of pRb and E2F1with binding to the E2F1 promoter, by stimulating pRb association. ATO also effected the phosphorylation of pRb at S608 and T373 residues and association of E2F1, pRb, and p53, simultaneously. However, in p53-knockdown NB4 cells, ATO did not significantly reduce E2F1 and cyclin E expression. Our findings demonstrate that ATO inhibits APL cell growth through reduced expression of E2F1, cyclin E, and stimulation of pRb. It also effected both interaction and association of E2F1, pRb, and p53 by phosphorylation of pRb at T373 and S608 residues and reduced phosphorylation of PI3K signaling molecules. This novel mode of action of ATO in APL cells may be useful for designing new APL drugs.

Correlations between Urinary Monoethylhexyl Phthalate Concentration in Healthy Individuals, Individuals with Colorectal Adenomas, and Individuals with Colorectal Cancer

Colorectal cancer (CRC) is the third leading cause of cancer death in Taiwan. A recent study suggested a link between exposure to endocrine-disrupting chemicals (EDCs) and increased susceptibility to pathology. Exposure to di-(2-ethylhexyl) phthalate (DEHP), an EDC and plasticizer widely used in consumer products, has been reported to be significantly positively correlated with increased risks of various cancers. We explored this connection of DEHP exposure with the development of CRC through the detection of urinary monoethylhexyl phthalate (MEHP), a potent metabolite of DEHP. Participants comprised 221 individuals recruited between October 2016 and November 2019 from a single institution. Overall, urinary MEHP concentrations were significantly higher in patients with CRC than in the patients with adenoma or healthy participants (both P < 0.001). Higher exposure to DEHP may contribute to the occurrence of CRC. Urinary MEHP detection may serve as a beneficial noninvasive indicator of increased CRC risk.

Practical Review on Preclinical Human 3D Glioblastoma Models: Advances and Challenges for Clinical Translation

Fifteen years after the establishment of the Stupp protocol as the standard of care to treat glioblastomas, no major clinical advances have been achieved and increasing patient’s overall survival remains a challenge. Nevertheless, crucial molecular and cellular findings revealed the intra-tumoral and inter-tumoral complexities of these incurable brain tumors, and the essential role played by cells of the microenvironment in the lack of treatment efficacy. Taking this knowledge into account, fulfilling gaps between preclinical models and clinical samples is necessary to improve the successful rate of clinical trials. Since the beginning of the characterization of brain tumors initiated by Bailey and Cushing in the 1920s, several glioblastoma models have been developed and improved. In this review, we focused on the most widely used 3D human glioblastoma models, including spheroids, tumorospheres, organotypic slices, explants, tumoroids and glioblastoma-derived from cerebral organoids. We discuss their history, development and especially their usefulness.

Di(2-ethylhexyl) phthalate (DEHP) increases proliferation of epithelial breast cancer cells through progesterone receptor dysregulation

The di(2-ethylhexyl) phthalate (DEHP) is a plasticizer incorporated to plastic matrices of widely used consumer products. However, it is gradually released from these products, resulting in a chronic exposure for humans. Although DEHP, similar to other members of the phthalates family, is generally considered as an endocrine disruptor, the mechanisms implicated in its toxicity are yet poorly understood. Our objective was to determine the effects of an exposure to DEHP and to one of its major metabolite, the mono(2-ethylhexyl) phthalate (MEHP) on markers involved in breast carcinogenesis. T-47D cells were exposed to environmentally relevant and higher doses of DEHP and MEHP (0.1-10 000 nM) for 4 days. Our results showed that an exposure to 10 000 nM of DEHP and 0.1 nM of MEHP significantly increased the proliferation of T-47D cells, without inducing apoptosis. In addition, a significant increase in the protein levels of the isoform A of the progesterone receptor (PR) and of nuclear levels of PR were observed in T-47D cells exposed to 10 000 nM of DEHP. Importantly, the increased proliferation and nuclear levels of PR were totally and partially inhibited, respectively, by Mifepristone, a PR antagonist. These results suggest that an exposure to DEHP or MEHP increase cell proliferation by activating PR signaling, which could potentially increase the risks to develop breast cancer. The mechanism of activation of the progesterone pathway by DEHP and the long-term consequences of this activation remained to be elucidated.

The cellular effects of novel triazine nitrogen mustards in glioblastoma LBC3, LN-18 and LN-229 cell lines

1,3,5-triazine is an important heterocyclic skeleton for mono, two or three 2-chloroethylamine groups. The study presented here provides novel information on cellular effects of 1,3,5-triazine with mono, two or three 2-chloroethylamine groups in glioblastoma LBC3, LN-18 and LN-229 cell lines. In our study, the most cytotoxic effect was observed in 1,3,5-triazine with three 2-chloroethylamine groups (12f compound). It has been demonstrated that 12f induce time- and dose-dependent cytotoxicity in all investigated glioma cell lines. Apart from that in glioblastoma cells, treated with 12f compound, we noticed strong induction of apoptosis. In conclusion, this research provides novel information concerning cellular effects of apoptosis in LBC3, LN-18 and LN-229 cell lines. Moreover, we suggest that 12f compound may be a candidate for further evaluation as an effective chemotherapeutic agent for human glioblastoma cells.

Cell Motility Facilitated by Mono(2-ethylhexyl) Phthalate via Activation of the AKT-β-Catenin-IL-8 Axis in Colorectal Cancer

Di(2-ethylhexyl) phthalate (DEHP) is a common plasticizer that is widely used in many consumer products and medical devices. Humans can be exposed to DEHP through ingestion, inhalation, or dermal absorption. Previous studies on DEHP have focused on its role as an endocrine-disrupting chemical leading to endocrine-related diseases. However, the correlation between DEHP exposure and the progression of colorectal cancer (CRC) is largely unknown. The aim of this study was to investigate the effects of mono(2-ethylhexyl) phthalate (MEHP), an active metabolite of DEHP, on the progression of CRC. Our results showed that treatment with MEHP enriched the population of cancer-stem-cell (CSC)-like cells and upregulated IL-8 expression by inducing the AKT-β-catenin-TCF4 signaling pathway. Blocking β-catenin-TCF4-mediated IL-8 expression reversed the MEHP-induced migration and enrichment of CSC-like cells. Consistent with the in vitro data, DEHP treatment increased the levels of nuclear β-catenin, polyp formation, and invasive adenocarcinoma in a mouse model. Our results suggest that MEHP facilitates the progression of CRC through AKT-β-catenin signaling.

Trisenox disrupts MDM2-DAXX-HAUSP complex and activates p53, cell cycle regulation and apoptosis in acute leukemia cells

Trisenox (TX) has been used in the treatment of both de novo and relapsed acute promyelocytic leukemia (APL) patients. Using in vitro APL cell lines model in this research, we report on a new target of TX action through disruption of MDM2-DAXX-HAUSP complex, degradation of MDM2, and activation of p53 expression. TX–induced stress signal was transmitted by protein kinase (ATM & ATR) and phosphorylation of its downstream targets CHK1, CHK2, ATM, and ATR, respectively at the Ser 345, Thr68, Ser1981 and Ser 428 residues involved in complex disruption and p53 up-regulation. TX-activated p53 led to cell cycle arrest and apoptosis in APL cells. Our results showed that TX inhibited cell proliferation, disrupted complex molecules expression and association in APL cells. Our functional studies indicated that TX-induced down-regulation of complex molecules expression was mostly neutralized in both p53 knockdown NB4 cells and nutilin-3 treated KG1a cells. Hence our findings provide a functional evidence of TX action on cell cycle regulation and apoptosis in APL cells. This novel target of TX activity may be useful for designing new APL drugs.

The Impact of Di(2-ethylhexyl)phthalate on Cancer Progression

Di(2-ethylhexyl)phthalate (DEHP), a widely used plasticizer, mainly serves as an additive to render polyvinyl chloride (PVC) soft and flexible. PVC plastics have become ubiquitous in our modern society. Yet, the leaching of DEHP from PVC-based consumables ultimately results in the deposition in certain tissues via inadvertent applications. Health risks for human populations exposed to DEHP has been assumed by studies on rodents and other species, including the DEHP-induced developmental dysregulation, reproductive impairments, tumorigenesis, and diseases in a transgenerational manner. In this review, we comprehensively summarize the accumulated literature regarding the multifaceted roles of DEHP in the activation of the nuclear receptors, the alteration of the redox homeostasis, epigenetic modifications and the acquisition of chemoresistance.

Up regulation of IL-6 is involved in di (2-ethylhexyl) phthalate (DEHP) induced migration and invasion of non small cell lung cancer (NSCLC) cells

Di (2-ethylhexyl) phthalate (DEHP), which is widely used in polyvinyl chloride materials, can be easily accumulated into human body. Lung cancer cells can be directly exposed to DEHP via inhalation, however, the effects and related mechanisms of DEHP on the progression of non small cell lung cancer (NSCLC) were not illustrated. Our present study revealed that DEHP less than 10^-4M had no significant effect on the proliferation of A549 or H1299 cells, while nanomolar DEHP can trigger the migration and invasion of NSCLC cells. DEHP treatment also increased the expression of interleukin-6 (IL-6) and IL-8. Silencing of IL-6, while not IL-8, can attenuate DEHP induced migration and invasion of NSCLC cells. This was confirmed by result that neutralization antibody of IL-6, while not anti-IL-8, attenuated DEHP induced invasion of A549 cells. The inhibitor of NF-κB, while not ERK1/2 or Akt, abolished DEHP induced up regulation of IL-6 and invasion of NSCLC cells. DEHP treatment can increase the phosphorylation, nuclear localization, and transcriptional activities of p65, one of the major parts of NF-κB complex. Collectively, our study revealed that DEHP can stimulate NSCLC migration and invasion via NF-κB mediated up regulation of IL-6.

Promotion of breast cancer cells MDA-MB-231 invasion by di(2-ethylhexyl)phthalate through matrix metalloproteinase-2/-9 overexpression

Di(2-ethylhexyl)phthalate (DEHP) is an estrogenic chemical that is widely used in polyvinyl products. We aimed to determine the mechanisms behind the effects of DEHP on ERα-negative breast cancer cells MDA-MB-231 invasion and matrix metalloproteinases-2/-9 (MMP-2/-9) up-regulation in this study. Transwell assay indicated that DEHP exposure (>50 μg/ml) significantly enhanced the invasion ability of MDA-MB-231 cells. Quantitative real-time PCR (qPCR) and western blotting revealed that MMP-2/-9 is overexpressed in mRNA and protein levels after DEHP treatment. Gelatin zymography consistently demonstrated that DEHP exposure also enhances the activity of MMP-2/-9. Immunofluorescence assay showed that DEHP could accelerate NF-kappaB (NF-κB) subunits-p65 translocation into the nucleus, which is confirmed by western blotting assay, suggesting that the ratio of nuclear/cytosolic level of p65 was significantly increased. Furthermore, the invasion and MMP-2/-9 overexpression of MDA-MB-231 cells after DEHP-treated were reversed by the NF-κB chemical inhibitor JSH-23 via drug inhibition assay. This study suggested that DEHP could promote ERα-negative breast cancer cells MDA-MB-231 invasion through activating NF-κB and MMP-2/-9 overexpression.

The life and works of S100P - from conception to cancer

Since its discovery in 1992, the small, 10.4 kDa calcium-binding protein S100P has gained the attention of researchers from different scientific fields due to its potential roles in both healthy and neoplastic tissues. Although not ubiquitously expressed, in tissues where it is present, S100P is associated with distinct changes in cellular behaviour. In this review we have summarized the evolutionary history of S100P, its expression and involvement in implantation and human embryonic development, as well as important functions in normal tissue and cancer. Finally, we have demonstrated its pivotal role as a potential diagnostic and therapeutic target, which opens promising avenues for further fruitful research on S100P.

Flat cells come full sphere: Are mutant cytoskeletal-related proteins oncoprotein-monsters or useful immunogens?

Osteogenesis imperfecta is inherited as a dominant disease because if one allele is mutated, it contributes a mutant, destructive subunit polypeptide to collagen, which requires many subunits to form normal, polymeric, collagenous structures. Recent cancer genome atlas (TCGA) data indicate that cytoskeletal-related proteins are among the most commonly mutated proteins in human cancers, in distinct mutation frequency groups, i.e., including low mutation frequency groups. Part of the explanation for this observation is likely to be the fact that many of the coding regions for these proteins are very large, and indeed, it is likely these coding regions are mutated in many cells that never become cancerous. However, it would not be surprising if mutations in cytoskeletal proteins, when combined with oncoprotein or tumor suppressor protein mutations, had significant impacts on cancer development, for a number of reasons, including results obtained almost 5 decades ago indicating that well-spread cells in tissue culture, with well-formed cytoskeletons, were less tumorigenic than spherical cells with disrupted cytoskeletons. This raises the question, are mutant cytoskeletal proteins, which would likely interfere with polymer formation, a new class of oncoproteins, in particular, dominant negative oncoproteins? If these proteins are so commonly mutant, could they be the bases for common cancer vaccines?

Occurrence, fate, behavior and ecotoxicological state of phthalates in different environmental matrices

Because of their large and widespread application, phthalates or phthalic acid esters (PAEs) are ubiquitous in all the environmental compartements. They have been widely detected throughout the worldwide environment. Indoor air where people spend 65-90% of their time is also highly contaminated by various PAEs released from plastics, consumer products as well as ambient suspended particulate matter. Because of their widespread application, PAEs are the most common chemicals that humans are in contact with daily. Based on various exposure mechanisms, including the ingestion of food, drinking water, dust/soil, air inhalation and dermal exposure the daily intake of PAEs may reach values as high as 70 μg/kg/day. PAEs are involved in endocrine disrupting effects, namely, upon reproductive physiology in different species of fish and mammals. They also present a variety of additional toxic effects for many other species including terrestrial and aquatic fauna and flora. Therefore, their presence in the environment has attracted considerable attention due to their potential impacts on ecosystem functioning and on public health. This paper is a synthesis of the extensive literature data on behavior, transport, fate and ecotoxicological state of PAEs in environmental matrices: air, water, sediment, sludge, wastewater, soil, and biota. First, the origins and physicochemical properties of PAEs that control the behavior, transport and fate in the environment are reviewed. Second, the compilation of data on transport and fate, adverse environmental and human health effects, legislation, restrictions, and ecotoxicological state of the environment based on PAEs is presented.