Phospholipase D1 is upregulated by vorinostat and confers resistance to vorinostat in glioblastoma.
Ontology highlight
ABSTRACT:
SUBMITTER: Kang DW
PROVIDER: S-EPMC7692931 | biostudies-literature | 2021 Jan
REPOSITORIES: biostudies-literature
Publications
Phospholipase D1 is upregulated by vorinostat and confers resistance to vorinostat in glioblastoma.
Kang Dong Woo DW Hwang Won Chan WC Noh Yu Na YN Kang Youra Y Jang Younghoon Y Kim Jung-Ae JA Min Do Sik DS
Journal of cellular physiology 20200901 1
Glioblastoma (GBM) is an aggressive brain tumor and drug resistance remains a major barrier for therapeutics. Epigenetic alterations are implicated in GBM pathogenesis, and epigenetic modulators including histone deacetylase (HDAC) inhibitors are exploited as promising anticancer therapies. Here, we demonstrate that phospholipase D1 (PLD1) is a transcriptional target of HDAC inhibitors and confers resistance to HDAC inhibitor in GBM. Treatment of vorinostat upregulates PLD1 through PKCζ-Sp1 axis ...[more]
Similar Datasets
Project description:Resistance of glioblastoma to the chemotherapeutic compound temozolomide is associated with the presence of glioblastoma stem cells in glioblastoma and is a key obstacle for the poor prognosis of glioblastoma. Here, we show that phospholipase D1 is elevated in CD44High glioblastoma stem cells and in glioblastoma, especially recurring glioblastoma. Phospholipase D1 elevation positively correlated with the level of CD44 and poor prognosis in glioblastoma patients. Temozolomide significantly upregulated the expression of phospholipase D1 in the low and moderate CD44 populations of glioblastoma stem cells, but not in the CD44High population in which phospholipase D1 is highly expressed. Phospholipase D1 conferred resistance to temozolomide in CD44High glioblastoma stem cells and increased their self-renewal capacity and maintenance. Phospholipase D1 expression significantly correlated with levels of temozolomide resistance factors, which were suppressed by microRNA-320a and -4496 induced by phospholipase D1 inhibition. Genetic and pharmacological targeting of phospholipase D1 attenuated glioblastoma stem cell-derived intracranial tumors of glioblastoma using the microRNAs, and improved survival. Treatment solely with temozolomide produced no benefits on the glioblastoma, whereas in combination, phospholipase D1 inhibition sensitized glioblastoma stem cells to temozolomide and reduced glioblastoma tumorigenesis. Together, these findings indicate that phospholipase D1 inhibition might overcome resistance to temozolomide and represents a potential treatment strategy for glioblastoma. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.
| S-EPMC7693208 | biostudies-literature
Project description:Although macroautophagy is known to be an essential degradative process whereby autophagosomes mediate the engulfment and delivery of cytoplasmic components into lysosomes, the lipid changes underlying autophagosomal membrane dynamics are undetermined. Here, we show that phospholipase D1 (PLD1), which is primarily associated with the endosomal system, partially relocalizes to the outer membrane of autophagosome-like structures upon nutrient starvation. The localization of PLD1, as well as the starvation-induced increase in PLD activity, are altered by wortmannin, a phosphatidylinositol 3-kinase inhibitor, suggesting PLD1 may act downstream of Vps34. Pharmacological inhibition of PLD and genetic ablation of PLD1 in mouse cells decreased the starvation-induced expansion of LC3-positive compartments, consistent with a role of PLD1 in the regulation of autophagy. Furthermore, inhibition of PLD results in higher levels of Tau and p62 aggregates in organotypic brain slices. Our in vitro and in vivo findings establish a role for PLD1 in autophagy.
| S-EPMC3328354 | biostudies-literature
Project description:The efficacy of osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor, has been evaluated in glioblastoma (GBM) through preclinical and clinical trials. However, the underlying mechanism of osimertinib-induced GBM cell death and the underlying resistance mechanism to osimertinib remains unclear. Here, we demonstrate that Osimertinib induces paraptosis in GBM cells, as evidenced by the formation of cytoplasmic vacuoles, accumulation of ubiquitinated proteins, and upregulation of endoplasmic reticulum (ER) stress markers like CHOP. Additionally, neither apoptosis nor autophagy was involved in the osimertinib-induced cell death. RNAseq analysis revealed ER stress was the most significantly downregulated pathway upon exposure to osimertinib. Consistently, pharmacologically targeting the PERK-eIF2α axis impaired osimertinib-induced paraptosis. Notably, we show that the expression of thyroid receptor-interacting protein 13 (TRIP13), an AAA+ATPase, alleviated osimertinib-triggered paraptosis, thus conferring resistance. Intriguingly, MK-2206, an AKT inhibitor, downregulated TRIP13 levels and synergized with Osimertinib to suppress TRIP13-induced high GBM cell growth in vitro and in vivo. Together, our findings reveal a novel mechanism of action associated with the anti-GBM effects of osimertinib involving ER stress-regulated paraptosis. Furthermore, we identify a TRIP13-driven resistance mechanism against Osimertinib in GBM and offer a combination strategy using MK-2206 to overcome such resistance.
| S-EPMC10480197 | biostudies-literature
Project description:BackgroundOncogenic activation of phosphatidylinositol-3 kinase (PI3K) signaling plays a pivotal role in the development of glioblastoma (GBM). However, pharmacological inhibition of PI3K has so far not been therapeutically successful due to adaptive resistance through a rapid rewiring of cancer cell signaling. Here we identified that WEE1 is activated after transient exposure to PI3K inhibition and confers resistance to PI3K inhibition in GBM.MethodsPatient-derived glioma-initiating cells and established GBM cells were treated with PI3K inhibitor or WEE1 inhibitor alone or in combination, and cell proliferation was evaluated by CellTiter-Blue assay. Cell apoptosis was analyzed by TUNEL, annexin V staining, and blotting of cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase. Both subcutaneous xenograft and orthotropic xenograft studies were conducted to evaluate the effects of the combination on tumorigenesis; the tumor growth was monitored by bioluminescence imaging, and tumor tissue was analyzed by immunohistochemistry to validate signaling changes.ResultsPI3K inhibition activates WEE1 kinase, which in turn phosphorylates cell division control protein 2 homolog (Cdc2) at Tyr15 and inhibits Cdc2 activity, leading to G2/M arrest in a p53-independent manner. WEE1 inhibition abrogated the G2/M arrest and propelled cells to prematurely enter into mitosis and consequent cell death through mitotic catastrophe and apoptosis. Additionally, combination treatment significantly suppressed tumor growth in a subcutaneous model but not in an intracranial model due to limited blood-brain barrier penetration.ConclusionsOur findings highlight WEE1 as an adaptive resistant gene activated after PI3K inhibition, and inhibition of WEE1 potentiated the effectiveness of PI3K targeted inhibition, suggesting that a combinational inhibition of WEE1 and PI3K might allow successful targeted therapy in GBM.
| S-EPMC5761544 | biostudies-literature
Project description:BackgroundCyclic-dependent kinase (CDK) 4/6 kinases, as the critical drivers of the cell cycle, are involved in the tumor progression of various malignancies. Pharmacologic inhibitors of CDK4/6 have shown significant clinical prospects in treating hormone receptor-positive and human epidermal growth factor receptor-negative (HR + /HER2-) breast cancer (BC) patients. However, acquired resistance to CDK4/6 inhibitors (CDK4/6i), as a common issue, has developed rapidly. It is of great significance that the identification of novel therapeutic targets facilitates overcoming the CDK4/6i resistance. PARP1, an amplified gene for CDK4/6i-resistant patients, was found to be significantly upregulated during the construction of CDK4/6i-resistant strains. Whether PARP1 drives CDK4/6i resistance in breast cancer is worth further study.MethodPARP1 and p-YB-1 protein levels in breast cancer cells and tissues were quantified using Western blot (WB) analysis, immunohistochemical staining (IHC) and immunofluorescence (IF) assays. Bioinformatics analyses of Gene Expression Profiling Interactive Analysis (GEPIA), Genomics of Drug Sensitivity in Cancer (GDSC) and Cancer Cell Line Encyclopedia (CCLE) datasets were applied to explore the relationship between YB-1/PARP1 protein levels and CDK4/6i IC50. Cell Counting Kit-8 (CCK-8) and crystal violet staining assays were performed to evaluate cell proliferation rates and drug killing effects. Flow cytometry assays were conducted to assess apoptosis rates and the G1/S ratio in the cell cycle. An EdU proliferation assay was used to detect the DNA replication ratio after treatment with PARP1 and YB-1 inhibitors. A ChIP assay was performed to assess the interaction of the transcription factor YB-1 and associated DNA regions. A double fluorescein reporter gene assay was designed to assess the influence of WT/S102A/S102E YB-1 on the promoter region of PARP1. Subcutaneous implantation models were applied for in vivo tumor growth evaluations.ResultsHere, we reported that PARP1 was amplified in breast cancer cells and CDK4/6i-resistant patients, and knockdown or inhibition of PARP1 reversed drug resistance in cell experiments and animal models. In addition, upregulation of transcription factor YB-1 also occurred in CDK4/6i-resistant breast cancer, and YB-1 inhibition can regulate PARP1 expression. p-YB-1 and PARP1 were upregulated when treated with CDK4/6i based on the WB and IF results, and elevated PARP1 and p-YB-1 were almost simultaneously observed during the construction of MCF7AR-resistant strains. Inhibition of YB-1 or PAPR1 can cause decreased DNA replication, G1/S cycle arrest, and increased apoptosis. We initially confirmed that YB-1 can bind to the promoter region of PARP1 through a ChIP assay. Furthermore, we found that YB-1 phosphorylated at S102 was crucial for PARP1 transcription according to the double fluorescein reporter gene assay. The combination therapy of YB-1 inhibitors and CDK4/6i exerted a synergistic antitumor effect in vitro and in vivo. The clinical data suggested that HR + /HER2- patients with low expression of p-YB-1/PARP1 may be sensitive to CDK4/6i in breast cancer.ConclusionThese findings indicated that a ''YB-1/PARP1'' loop conferred resistance to CDK4/6 inhibitors. Furthermore, interrupting the loop can enhance tumor killing in the xenograft tumor model, which provides a promising strategy against drug resistance in breast cancer.
| S-EPMC10687910 | biostudies-literature
Project description:Previously, we reported that phospholipase D1 (PLD1) and PLD2 inhibition by selective PLD1 and PLD2 inhibitors could prevent platelet aggregation in humans, but not in mice. Moreover, only the PLD1 inhibitor, but not PLD2 inhibitor, could effectively prevent thrombus formation in mice, indicating that PLD might play different roles in platelet function in humans and mice. Although PLD1 and PLD2 were reported to be implicated in thrombotic events, the role of PLD in mice remains not completely clear. Here, we investigated the role of PLD1 and PLD2 in acute pulmonary thrombosis and transient middle cerebral artery occlusion-induced brain injury in mice. The data revealed that inhibition of PLD1, but not of PLD2, could partially prevent pulmonary thrombosis-induced death. Moreover, concurrent PLD1 and PLD2 inhibition could considerably increase survival rate. Likewise, inhibition of PLD1, but not PLD2, partially improved ischemic stroke and concurrent inhibition of PLD1, and PLD2 exhibited a relatively better protection against ischemic stroke, as evidenced by the infarct size, brain edema, modified neurological severity score, rotarod test, and the open field test. In conclusion, PLD1 might play a more important role than PLD2, and both PLD1 and PLD2 could act synergistically or have partially redundant functions in regulating thrombosis-relevant events.
| S-EPMC7555624 | biostudies-literature
Project description:Although targeted therapies have revolutionized cancer treatment, overcoming acquired resistance remains a major clinical challenge. EZH2 inhibitors (EZH2i), EPZ-6438 and GSK126, are currently in the early stages of clinical evaluation and the first encouraging signs of efficacy have recently emerged in the clinic. To anticipate mechanisms of resistance to EZH2i, we used a forward genetic platform combining a mutagenesis screen with next generation sequencing technology and identified a hotspot of secondary mutations in the EZH2 D1 domain (Y111 and I109). Y111D mutation within the WT or A677G EZH2 allele conferred robust resistance to both EPZ-6438 and GSK126, but it only drove a partial resistance within the Y641F allele. EZH2 mutants required histone methyltransferase (HMT) catalytic activity and the polycomb repressive complex 2 (PRC2) components, SUZ12 and EED, to drive drug resistance. Furthermore, D1 domain mutations not only blocked the ability of EZH2i to bind to WT and A677G mutant, but also abrogated drug binding to the Y641F mutant. These data provide the first cellular validation of the mechanistic model underpinning the oncogenic function of WT and mutant EZH2. Importantly, our findings suggest that acquired-resistance to EZH2i may arise in WT and mutant EZH2 patients through a single mutation that remains targetable by second generation EZH2i.
| S-EPMC4741719 | biostudies-literature
Project description:BackgroundGlioblastoma is the most common and aggressive type of primary brain tumor in adults. A key problem is the capacity of glioma cells to inactivate the body's immune response. The complement system acts as a functional bridge between the innate and adaptive immune response. Still, the role of the complement system has almost been forgotten in glioma research. In our present study, we hypothesize that C1 inactivator (C1-IA) is upregulated in astrocytoma grade IV, and that its inhibition of the complement system has beneficial effects upon survival.Methods and resultsWe have explored this hypothesis both on gene and protein levels and found an upregulation of C1-IA in human glioblastoma cells using data from a publicly available database and our own mRNA material from glioblastoma patients. Furthermore, we demonstrated the presence of C1-IA by using immunohistochemistry on glioma cells from both humans and rats in vitro. Finally, we could demonstrate a significantly increased survival in vivo in animals inoculated intracerebrally with glioma cells pre-coated with C1-IA antibodies as compared to control animals.ConclusionsOur findings indicate that overexpression of C1-IA is present in glioblastomas. This could be demonstrated both at the gene level from patients with glioblastoma, on mRNA level and with immunohistochemistry. Treatment with antibodies against C1-IA had beneficial effects on survival when tested in vivo.
| S-EPMC5589086 | biostudies-literature
Project description:The inflammasome is a specialized multiprotein oligomer that regulates IL-1β production. Although regulation of the inflammasome is related to crucial inflammatory disorders such as sepsis, pharmacological inhibitors that effectively inhibit inflammasome activity are limited. Here, we evaluated the effects of a phospholipase D1 (PLD1)-selective inhibitor (VU0155069) against sepsis and inflammasome activation. VU0155069 strongly enhances survival rate in cecal ligation and puncture (CLP)-induced sepsis by inhibiting lung inflammation, leukocyte apoptosis, and the production of proinflammatory cytokines, especially IL-1β. VU0155069 also significantly blocked IL-1β production, caspase-1 activation, and pyroptosis caused by several inflammasome-activating signals in the bone marrow-derived macrophages (BMDMs). However, VU0155069 did not affect LPS-induced activation of signaling molecules such as MAPK, Akt, NF-κB, and NLRP3 expression in the BMDMs. VU0155069 also failed to affect mitochondrial ROS generation and calcium increase caused by nigericin or ATP, and subsequent ASC oligomerization caused by several inflammasome-activating signals. VU0155069 indirectly inhibited caspase-1 activity caused by LPS + nigericin in BMDMs independent of PLD1 activity. We demonstrated that a PLD1 inhibitor, VU0155069, shows anti-septic activity as well as inflammasome-inhibiting effects. Our results suggest that VU0155069 can be considered a novel inflammasome inhibitor.
| S-EPMC6778193 | biostudies-literature
Project description:Despite advances in therapy, glioblastoma remains an incurable disease with a dismal prognosis. Recent studies have implicated cancer stem cells within glioblastoma (glioma stem cells, GSCs) as mediators of therapeutic resistance and tumor progression. In this study, we investigated the role of the transforming growth factor-? (TGF-?) superfamily, which has been found to play an integral role in the maintenance of stem cell homeostasis within multiple stem cell systems, as a mediator of stem-like cells in glioblastoma. We find that BMP and TGF-? signaling define divergent molecular and functional identities in glioblastoma, and mark relatively quiescent and proliferative GSCs, respectively. Treatment of GSCs with BMP inhibits cell proliferation, but does not abrogate their stem-ness, as measured by self-renewal and tumorigencity. Further, BMP pathway activation confers relative resistance to radiation and temozolomide chemotherapy. Our findings define a quiescent cancer stem cell population in glioblastoma that may be a cellular reservoir for tumor recurrence following cytotoxic therapy.
| S-EPMC6787003 | biostudies-literature