Dataset Information

Key roles for the lipid signaling enzyme phospholipase d1 in the tumor microenvironment during tumor angiogenesis and metastasis.

ABSTRACT: Angiogenesis inhibitors, which target tumor cells, confer only short-term benefits on tumor growth. We report that ablation of the lipid signaling enzyme phospholipase D1 (PLD1) in the tumor environment compromised the neovascularization and growth of tumors. PLD1 deficiency suppressed the activation of Akt and mitogen-activated protein kinase signaling pathways by vascular endothelial growth factor in vascular endothelial cells, resulting in decreased integrin-dependent cell adhesion to, and migration on, extracellular matrices, as well as reduced tumor angiogenesis in a xenograft model. In addition, mice lacking PLD1 incurred fewer lung metastases than did wild-type mice. Bone marrow transplantation and binding studies identified a platelet-derived mechanism involving decreased tumor cell-platelet interactions, in part because of impaired activation of ?IIb?3 integrin in platelets, which decreased the seeding of tumor cells into the lung parenchyma. Treatment with a small-molecule inhibitor of PLD1 phenocopied PLD1 deficiency, efficiently suppressing both tumor growth and metastasis in mice. These findings reveal that PLD1 in the tumor environment promotes tumor growth and metastasis and, taken together with previous reports on the roles of PLD in tumor cell-intrinsic adaptations to stress, suggest the potential use of PLD inhibitors as cancer therapeutics.

SUBMITTER: Chen Q

PROVIDER: S-EPMC3721670 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Key roles for the lipid signaling enzyme phospholipase d1 in the tumor microenvironment during tumor angiogenesis and metastasis.

Chen Qin Q Hongu Tsunaki T Sato Takanobu T Zhang Yi Y Ali Wahida W Cavallo Julie-Ann JA van der Velden Adrianus A Tian Huasong H Di Paolo Gilbert G Nieswandt Bernhard B Kanaho Yasunori Y Frohman Michael A MA

Science signaling 20121106 249

Angiogenesis inhibitors, which target tumor cells, confer only short-term benefits on tumor growth. We report that ablation of the lipid signaling enzyme phospholipase D1 (PLD1) in the tumor environment compromised the neovascularization and growth of tumors. PLD1 deficiency suppressed the activation of Akt and mitogen-activated protein kinase signaling pathways by vascular endothelial growth factor in vascular endothelial cells, resulting in decreased integrin-dependent cell adhesion to, and mi ...[more]

PMID: 23131846

Similar Datasets

Project description:Objective：Phospholipase D1 (PLD1), a phosphatidylcholine-hydrolyzing enzyme, has been found to be involved in cellular lipid metabolism. However, how PLD1 involves in hepatocyte lipid metabolism and thus affects non-alcoholic fatty liver diseases (NAFLD) has not been explicitly explored. Method: NAFLD is induced in hepatocyte-specific Pld1 knockout (Pld1(H)-KO) mice or control (Pld1-Flox) mice with a high fat diet (HFD) for 20 weeks. Plasma glucose and lipid levels, liver lipid and function parameters and inflammation- and fibrogenesis-related gene expression levels were studied. Changes in lipid composition of liver were detected by lipidomic analyses. Changes in gene expression profile were detected by mRNA sequencing. In vitro, alpha mouse liver 12 (AML12) cells were incubated with sodium palmitate (SP) to explore the mechanisms of PLD1 on development of NAFLD. The protein levels of PLD1 and CD36 were detected in the liver tissues of NAFLD patients. Finally, the therapeutic effect of NAFLD by inhibiting PLD with 5-Fluoro-2-indolyl deschlorohalopemide (FIPI) was examined. Results: PLD1 expression levels were increased in the liver tissues of NAFLD patients and the hepatocytes of HFD-induced mice. Compared with Pld1-Flox mice, Pld1(H)-KO mice exhibited lower plasma glucose and lipids levels, and decreased lipid accumulation, inflammation and fibrosis related gene expression levels in the liver tissues after HFD feeding. Inhibition of hepatocyte PLD1 significantly altered lipid composition, especially phosphatidic acids (PA) and lyso-PAs (LPA) levels in the liver tissues after NAFLD. Transcriptomic analysis showed that hepatocyte specific deficiency of PLD1 mainly decreased CD36 expression levels in the NAFLD liver tissues, which was confirmed at the protein and gene expression levels. In vitro, inhibition of PLD1 markedly decreased CD36 expression and lipid accumulation in SP treated AML12 cells. Furthermore, PA, the downstream product catalyzed by PLD1, increased the expression levels of CD36 and lipid accumulation in vitro, which was reversed by PPARγ antagonist. These suggested that PPARγ played an important role in transcriptional regulation of CD36 expression after PA stimulation. Finally, PLD inhibitor FIPI had significant therapeutic effect on HFD-induced NAFLD. Conclusion: Hepatocyte-specific deficiency of PLD1 ameliorates lipid accumulation and NAFLD development by inhibiting PPARγ/CD36 pathway conducted by PA.

Project description:BackgroundHigh tumor-infiltrating lymphocytes (TILs) and hemorrhage are important prognostic factors in patients who have undergone craniotomy for melanoma brain metastases (MBM) before 2011 at the University of Pittsburgh Medical Center (UPMC). We have investigated the prognostic or predictive role of these histopathologic factors in a more contemporary craniotomy cohort from the University of North Carolina at Chapel Hill (UNC-CH). We have also sought to understand better how various immune cell subsets, angiogenic factors, and blood vessels may be associated with clinical and radiographic features in MBM.MethodsBrain tumors from the UPMC and UNC-CH patient cohorts were (re)analyzed by standard histopathology, tumor tissue imaging, and gene expression profiling. Variables were associated with overall survival (OS) and radiographic features.ResultsThe patient subgroup with high TILs in craniotomy specimens and subsequent treatment with immune checkpoint inhibitors (ICIs, n=7) trended to have longer OS compared to the subgroup with high TILs and no treatment with ICIs (n=11, p=0.059). Bleeding was significantly associated with tumor volume before craniotomy, high melanoma-specific expression of basic fibroblast growth factor (bFGF), and high density of CD31+αSMA- blood vessels. Brain tumors with high versus low peritumoral edema before craniotomy had low (17%) versus high (41%) incidence of brisk TILs. Melanoma-specific expression of the vascular endothelial growth factor (VEGF) was comparable to VEGF expression by TILs and was not associated with any particular prognostic, radiographic, or histopathologic features. A gene signature associated with gamma delta (gd) T cells was significantly higher in intracranial than same-patient extracranial metastases and primary melanoma. However, gdT cell density in MBM was not prognostic.ConclusionsICIs may provide greater clinical benefit in patients with brisk TILs in MBM. Intratumoral hemorrhage in brain metastases, a significant clinical problem, is not merely associated with tumor volume but also with underlying biology. bFGF may be an essential pathway to target. VEGF, a factor principally associated with peritumoral edema, is not only produced by melanoma cells but also by TILs. Therefore, suppressing low-grade peritumoral edema using corticosteroids may harm TIL function in 41% of cases. Ongoing clinical trials targeting VEGF in MBM may predict a lack of unfavorable impacts on TIL density and/or intratumoral hemorrhage.

Project description:Pheochromocytomas (PHEOs) are relatively rare catecholamine-producing tumors derived from adrenal medulla. Tumor microenvironment (TME) including neoangiogenesis has been explored in many human neoplasms but not necessarily in PHEOs. Therefore, in this study, we examined tumor infiltrating lymphocytes (CD4 and CD8), tumor associated macrophages (CD68 and CD163), sustentacular cells (S100p), and angiogenic markers (CD31 and areas of intratumoral hemorrhage) in 39 cases of PHEOs in the quantitative fashion. We then compared the results with pheochromocytoma of the adrenal gland scaled score (PASS), grading system for pheochromocytoma and paraganglioma (GAPP) and the status of intra-tumoral catecholamine-synthesizing enzymes (TH, DDC, and PNMT) as well as their clinicopathological factors. Intratumoral CD8 (p = 0.0256), CD31 (p = 0.0400), and PNMT (p = 0.0498) status was significantly higher in PHEOs with PASS <4 than PASS ≧4. In addition, intratumoral CD8+ lymphocytes were also significantly more abundant in well-than moderately differentiated PHEO according to GAPP score (p = 0.0108) and inversely correlated with tumor size (p = 0.0257). Intratumoral CD68+ cells were significantly higher in PHEOs with regular or normal histological patterns than those not (p = 0.0370) and inversely correlated with tumor size (p = 0.0457). The status of CD163 was significantly positively correlated with that of CD8 positive cells (p = 0.0032). The proportion of intratumoral hemorrhage areas was significantly higher in PHEOs with PASS ≧4 (p = 0.0172). DDC immunoreactivity in tumor cells was significantly positively correlated with PASS score (p = 0.0356) and TH status was significantly higher in PHEOs harboring normal histological patterns (p = 0.0236) and cellular monotony (p = 0.0219) than those not. Results of our present study did demonstrate that abundant CD8+ and CD68+ cells could represent a histologically low-scored tumor. In particular, PHEOs with increased intratumoral hemorrhage should be considered rather malignant. In addition, abnormal catecholamine-producing status of tumor cells such as deficient PNMT and TH and increased DDC could also represent more aggressive PHEOs.

Dataset Information

Key roles for the lipid signaling enzyme phospholipase d1 in the tumor microenvironment during tumor angiogenesis and metastasis.

Publications

Key roles for the lipid signaling enzyme phospholipase d1 in the tumor microenvironment during tumor angiogenesis and metastasis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets