251
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Fan F, Wey JS, McCarty MF, Belcheva A, Liu W, Bauer TW, Somcio RJ, Wu Y, Hooper A, Hicklin DJ, Ellis LM. Expression and function of vascular endothelial growth factor receptor-1 on human colorectal cancer cells. Oncogene 2005; 24:2647-53. [PMID: 15735759 DOI: 10.1038/sj.onc.1208246] [Citation(s) in RCA: 256] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Vascular endothelial growth factor (VEGF) is associated with tumor angiogenesis and poor prognosis in human colorectal cancer (CRC). VEGF receptor-1 (VEGFR-1 or Flt-1) is a high-affinity receptor for VEGF and is typically considered specific to endothelial cells. Here we report the expression and function of VEGFR-1 in CRC cell lines. VEGFR-1 was expressed in all CRC cell lines studied as determined by RT-PCR, Western blot analysis, FACS, and ELISA. Treatment of the human CRC cell lines HT-29 and SW480 with VEGF-A (a ligand for both VEGFR-1 and -2) or VEGF-B (a ligand specific for VEGFR-1) led to activation of Erk-1/2, SAPK/JNK, and translocation of the p65 subunit of nuclear factor-kappaB into the nucleus. Both VEGF-A and -B led to significant induction of cell motility and invasiveness of CRC cells. Stimulation of cells with VEGF-A or -B also led to larger and more numerous colonies in soft agar. However, activation of VEGFR-1 did not increase CRC cell proliferation. In contrast to the previous paradigm that VEGFRs are not present on tumor cells of epithelial origin, we found that VEGFR-1 is present and functional on CRC cells, and activation by VEGF family ligands can activate processes involved in tumor progression and metastasis.
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Affiliation(s)
- Fan Fan
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030-4009, USA
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252
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Abstract
Angiogenesis or new blood vessel formation plays an essential role during embryogenesis, adult vascular remodeling and in several pathological disorders, as in tumor development. Although sprouting of blood vessels is the principal angiogenic mechanism, additional ones, such as the recruitment of bone marrow-derived cells, have recently been described. These processes are controlled by several molecules, although members of the VEGF family of angiogenic factors and its receptors seem to be the main mediators. Initially, VEGF receptors were described as endothelial specific; however, further studies have reported their presence in several types of cells of non-endothelial origin, such as tumor cells. This VEGF receptor altered expression has suggested an angiogenesis-independent growth advantage mechanism on certain types of cancers by the generation of autocrine loops. A possible role in tumorigenesis and a potential novel target in cancer therapy have been hypothesized. Detection of other receptors and molecules considered to be angiogenic players has also been observed on tumor cells. Currently, their clinical significance as well as their potential as therapeutic targets for the treatment of certain cancers is being evaluated, having in mind the future development of promising mechanism-based therapies. The aspects mentioned above are the main focus of this review, which aims to throw light on recent findings respecting angiogenesis and novel therapeutic approaches.
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Affiliation(s)
- Carla Costa
- Institute of Molecular Pathology and Immunology, University of Porto (IPATIMUP), Portugal
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253
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Chen J, De S, Brainard J, Byzova TV. Metastatic properties of prostate cancer cells are controlled by VEGF. ACTA ACUST UNITED AC 2005; 11:1-11. [PMID: 15500293 DOI: 10.1080/15419060490471739] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Mechanisms of metastasis, the major complication of prostate cancer, are poorly understood. In this study, we define molecular mechanisms that may contribute to the highly invasive potential of prostate cancer cells. Vascular endothelial growth factor (VEGF), its receptors (VEGFRs), and alpha5beta1 integrin were expressed by prostate cancer cells in vitro and by prostate tumors in vivo, and their expression was elevated at sites of bone metastasis compared to original prostate tumor. VEGF, through interaction with its receptors, regulated adhesive and migratory properties of the cancer cells. Specifically, the highly metastatic prostate cancer cell subline LNCaP-C4-2 showed a decreased adhesive but an enhanced migratory response to fibronectin, a ligand for alpha5beta1 integrin, compared to its nonmetastatic counterpart. A similar pattern was also observed when bone sialoprotein was used as a ligand in migration assays. Increased migration of metastatic prostate cancer cells to fibronectin and bone sialoprotein was regulated by VEGF via VEGFR-2. Tumor suppressor PTEN was involved in control of VEGF/VEGFR-2 stimulated prostate cancer cell adhesion as well as proliferation.
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Affiliation(s)
- Juhua Chen
- Joseph J. Jacobs Center for Thrombosis and Vascular Biology, Departments of Molecular Cardiology, Cardiology and Taussig Cancer Center, Cleveland Clinic Foundation, NB50, 9500 Euclid Avenue, Cleveland, OH 44195, USA
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254
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Tanno S, Ohsaki Y, Nakanishi K, Toyoshima E, Kikuchi K. Human small cell lung cancer cells express functional VEGF receptors, VEGFR-2 and VEGFR-3. Lung Cancer 2005; 46:11-9. [PMID: 15364128 DOI: 10.1016/j.lungcan.2004.03.006] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2003] [Revised: 03/12/2004] [Accepted: 03/18/2004] [Indexed: 12/20/2022]
Abstract
Studies have suggested that the vascular endothelial growth factors (VEGFs)/VEGF receptors (VEGF-Rs) system plays an important role in tumour growth and metastasis. We conducted the present study to clarify whether small cell lung cancer (SCLC) cells express functional VEGF-Rs and VEGFs, and their biological significance in the SCLC progression. We examined expression of VEGF and VEGF-C, and their receptors, VEGFR-2 and VEGFR-3, in five SCLC cell lines, NCI-H82, H209, H510, H526 and H660, by Western blotting. We evaluated whether hypoxic conditions up-regulate these protein expressions. We also examined whether VEGF addition and VEGF-D addition cause phosphorylation of the mitogen-activated protein kinase (MAPK) as well as VEGFR-2 and VEGFR-3. Further, we investigated whether VEGF addition and VEGF-D addition induced the proliferation and migration of the SCLC cells. VEGF, VEGF-C, VEGFR-2 and VEGFR-3 were detectable by Western blotting in all five SCLC cell lines,. The VEGF-Rs and VEGFs expression levels were increased by an incubation under hypoxic conditions in NCI-H82. VEGF addition and VEGF-D addition caused phosphorylation of MAPK as well as the VEGF-Rs themselves, and induced proliferation and migration of the SCLC cells. These results suggested potential of VEGF signal-pathway inhibitors as anti-cancer agents in SCLC treatment disturbing growth and migration of the cancer cells.
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Affiliation(s)
- Sachie Tanno
- First Department of Medicine, Asahikawa Medical College, 2-1-1-1 Midorigaoka, Higashi, Asahikawa 0788510, Japan
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255
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Hicklin DJ, Ellis LM. Role of the vascular endothelial growth factor pathway in tumor growth and angiogenesis. J Clin Oncol 2004; 23:1011-27. [PMID: 15585754 DOI: 10.1200/jco.2005.06.081] [Citation(s) in RCA: 2107] [Impact Index Per Article: 105.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
New blood vessel formation (angiogenesis) is a fundamental event in the process of tumor growth and metastatic dissemination. Hence, the molecular basis of tumor angiogenesis has been of keen interest in the field of cancer research. The vascular endothelial growth factor (VEGF) pathway is well established as one of the key regulators of this process. The VEGF/VEGF-receptor axis is composed of multiple ligands and receptors with overlapping and distinct ligand-receptor binding specificities, cell-type expression, and function. Activation of the VEGF-receptor pathway triggers a network of signaling processes that promote endothelial cell growth, migration, and survival from pre-existing vasculature. In addition, VEGF mediates vessel permeability, and has been associated with malignant effusions. More recently, an important role for VEGF has emerged in mobilization of endothelial progenitor cells from the bone marrow to distant sites of neovascularization. The well-established role of VEGF in promoting tumor angiogenesis and the pathogenesis of human cancers has led to the rational design and development of agents that selectively target this pathway. Studies with various anti-VEGF/VEGF-receptor therapies have shown that these agents can potently inhibit angiogenesis and tumor growth in preclinical models. Recently, an anti-VEGF antibody (bevacizumab), when used in combination with chemotherapy, was shown to significantly improve survival and response rates in patients with metastatic colorectal cancer and thus, validate VEGF pathway inhibitors as an important new treatment modality in cancer therapy.
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Affiliation(s)
- Daniel J Hicklin
- Department of Experimental Therapeutics, ImClone Systems Incorporated, New York, NY 10014, USA.
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256
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LeCouter J, Zlot C, Tejada M, Peale F, Ferrara N. Bv8 and endocrine gland-derived vascular endothelial growth factor stimulate hematopoiesis and hematopoietic cell mobilization. Proc Natl Acad Sci U S A 2004; 101:16813-8. [PMID: 15548611 PMCID: PMC528996 DOI: 10.1073/pnas.0407697101] [Citation(s) in RCA: 173] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bv8 and endocrine-gland-derived VEGF (EG-VEGF), or prokineticins, are two highly related, secreted proteins that we previously described as selective angiogenic mitogens. Here we describe the expression and functional characterization of Bv8 in peripheral blood cells, notably monocytes, neutrophils, and dendritic cells, and in the bone marrow. In human and mouse, the two Bv8 G protein-coupled receptors are expressed in hematopoietic stem cells and specific mature blood cells, including lymphocytes. Bv8 is highly expressed by neutrophils at sites of inflammation and can stimulate migration of monocytes, in a pertussis toxin-sensitive manner. Bv8, or EG-VEGF that shares the same receptors, increased numbers of colony-forming units granulocytic and monocytic in cultures of human or mouse hematopoietic stem cells. Systemic in vivo exposure to Bv8 or EG-VEGF resulted in significant increases in total leukocyte, neutrophil, and monocyte counts. Additionally, adenovirus (Av)Bv8 or AvEG-VEGF delivered just before 5-fluorouracil injury promoted the survival of hematopoietic cells and enhanced progenitor mobilization. In conclusion, Bv8 can promote survival and differentiation of the granulocytic and monocytic lineages. Bv8 potentially modulates growth, survival, and function of cells of the innate and adaptive immune systems, possibly through autocrine or paracrine signaling mechanisms.
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Affiliation(s)
- Jennifer LeCouter
- Department of Physiology, Genentech, Inc., South San Francisco, CA 94080, USA.
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257
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Rao Q, Zheng GG, Li G, Lin YM, Wu KF. Membrane-bound macrophage colony-stimulating factor mediated auto-juxtacrine downregulates matrix metalloproteinase-9 release on J6-1 leukemic cell. Exp Biol Med (Maywood) 2004; 229:946-53. [PMID: 15388891 DOI: 10.1177/153537020422900912] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Earlier studies indicate that J6-1 human leukemic cells proliferate and propagate via the membrane-bound macrophage colony-stimulating factor (M-CSF)-mediated auto-juxtacrine mechanism. Matrix metalloproteinases (MMPs) can modulate the activity of cell membrane molecules and influence many cellular behaviors. Therefore, we hypothesized that MMP may also be involved in the membrane-bound M-CSF-mediated juxtacrine mechanism. First, we investigated whether blocking of membrane-bound M-CSF by neutralizing antibody to M-CSF or M-CSF receptor and adding of exogenous M-CSF are able to influence MMP-9 release. Next, we determined whether MMP-9 participated in J6-1 cells proliferation and influence the shedding of membrane-bound M-CSF and its receptor. Current studies show that blockade of the interaction between membrane-bound M-CSF and M-CSF receptor by antibody to M-CSF or M-CSF receptor promotes MMP-9 release. Moreover, we demonstrated that because of M-CSF mediated juxtacrine, lack of MMP-9 promotes J6-1 cell proliferation, in which a decrease in the shedding of cell-surface M-CSFR is involved. Hence, we suggest that membrane-bound M-CSF inhibit MMP-9 release and down-regulated MMP-9 contribute to juxtacrine stimulating in leukemic cell growth.
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Affiliation(s)
- Qing Rao
- Institute of Hematology, Chinese Academy of Medical Sciences & Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, China
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258
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Dev IK, Dornsife RE, Hopper TM, Onori JA, Miller CG, Harrington LE, Dold KM, Mullin RJ, Johnson JH, Crosby RM, Truesdale AT, Epperly AH, Hinkle KW, Cheung M, Stafford JA, Luttrell DK, Kumar R. Antitumour efficacy of VEGFR2 tyrosine kinase inhibitor correlates with expression of VEGF and its receptor VEGFR2 in tumour models. Br J Cancer 2004; 91:1391-8. [PMID: 15328520 PMCID: PMC2409895 DOI: 10.1038/sj.bjc.6602109] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
During the development of indazolylpyrimidines as novel and potent inhibitors of vascular endothelial growth factor (VEGF) receptor-2 (VEGFR2) tyrosine kinase, we observed that some human tumour xenografts are more sensitive to VEGFR2 kinase inhibitors than others. A better understanding of the basis for this differential response may help to identify a predictive marker that would greatly aid in the identification of a suitable patient population for treatment. One representative compound from the indazolylpyrimidine series is GW654652 that inhibited all three VEGFRs with similar potency. The inhibition of VEGFR2 kinase by GW654652 was about 150 to >8800 more potent than the inhibition of eight other kinases tested. GW654652 inhibited VEGF- and bFGF-induced proliferation in endothelial cells with an IC(50) of 110 and 1980 nM, respectively, and has good pharmacokinetic profile in mouse and dog. We investigated the association between VEGF and VEGFR2 expression and the antitumour efficacy of GW654652, in various xenograft models. Statistically significant associations were observed between the antitumour efficacy of GW654652 in xenografts and VEGF protein (P=0.005) and VEGFR2 expression (P=0.041). The oral dose of GW654652 producing 50% inhibition of tumour growth (ED(50)) decreased with increasing levels of VEGF (r=-0.94); and, in contrast, the ED(50) increased with the increased expression of VEGFR2 (r=0.82). These results are consistent with the observed inverse correlation between VEGF and VEGFR2 expression in tumours. These findings support the hypothesis that VEGF and VEGFR2 expression by tumours may predict the therapeutic outcome of VEGFR kinase inhibitors.
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Affiliation(s)
- I K Dev
- GlaxoSmithKline, Five Moore Drive, Research Triangle Park, NC 27709, USA
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259
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Streicher KL, Sylte MJ, Johnson SE, Sordillo LM. Thioredoxin Reductase Regulates Angiogenesis by Increasing Endothelial Cell-Derived Vascular Endothelial Growth Factor. Nutr Cancer 2004; 50:221-31. [PMID: 15623470 DOI: 10.1207/s15327914nc5002_13] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Low selenium (Se) status increases angiogenesis by inducing the production of vascular endothelial growth factor (VEGF); however, the mechanism responsible for VEGF up-regulation has yet to be characterized. Se's ability to control cellular oxidative state through its incorporation into selenoproteins such as thioredoxin reductase (TrxR) may explain previous studies that connect Se status to tumor angiogenesis. Therefore, the focus of this study was to determine if altered VEGF expression and angiogenesis due to decreased Se levels are influenced by reduced TrxR activity. We found that chemical inhibition of TrxR in Se-sufficient endothelial cells (ECs) was associated with increases in VEGF and VEGF receptor expression, cell migration, proliferation, and angiogenesis to levels similar to those seen in Se-deficient ECs. Specific inhibition of glutathione peroxidase did not affect pro-angiogenic responses, indicating a unique role of the TrxR system during low Se status. These data correlate changes in TrxR activity with changes in VEGF expression and angiogenic development in ECs, which is significant because minimal mechanistic data exist that explain the role of Se in cancer prevention. Understanding the importance of the tumor microenvironment in contributing to angiogenic regulation has the potential to significantly impact breast cancer chemoprevention strategies by focusing on maintaining proper EC function within the mammary gland.
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Affiliation(s)
- Katie L Streicher
- Department of Veterinary Science, Pennsylvania State University, University Park, 16802, USA
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260
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Podar K, Anderson KC. The pathophysiologic role of VEGF in hematologic malignancies: therapeutic implications. Blood 2004; 105:1383-95. [PMID: 15471951 DOI: 10.1182/blood-2004-07-2909] [Citation(s) in RCA: 242] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Besides its role as an essential regulator of physiologic and pathologic angiogenesis, vascular endothelial growth factor (VEGF) triggers growth, survival, and migration of leukemia and multiple myeloma cells; plays a pivotal role in hematopoiesis; inhibits maturation of dendritic cells; and increases osteoclastic bone-resorbing activity as well as osteoclast chemotaxis. Dysregulation of VEGF expression and signaling pathways therefore plays an important role in the pathogenesis and clinical features of hematologic malignancies, in particular multiple myeloma. Direct and indirect targeting of VEGF and its receptors therefore may provide a potent novel therapeutic approach to overcome resistance to therapies and thereby improve patient outcome.
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Affiliation(s)
- Klaus Podar
- Dana-Farber Cancer Institute, Department of Medical Oncology, Jerome Lipper Multiple Myeloma Center, Boston, MA 02115, USA
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261
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Ribatti D, Scavelli C, Roccaro AM, Crivellato E, Nico B, Vacca A. Hematopoietic Cancer and Angiogenesis. Stem Cells Dev 2004; 13:484-95. [PMID: 15588506 DOI: 10.1089/scd.2004.13.484] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The growth of solid tumors is certainly angiogenesis dependent. However, the role of angiogenesis in the growth and survival of leukemias and other hematological malignancies has only been rendered evident since 1994 in a series of demonstrations showing that the progression of several forms is clearly related to their degree of angiogenesis. Here, we present an overview of the literature concerning the relationship between angiogenesis and disease progression in several hematological malignancies and the recent advances in antiangiogenesis in these diseases and we describe the most important active substances, preclinical and clinical data, and future perspectives.
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Affiliation(s)
- Domenico Ribatti
- Department of Human Anatomy and Histology, University of Bari Medical School, Bari, Italy.
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262
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Abstract
Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen in vitro and an angiogenic inducer in a variety of in vivo models. Hypoxia has been shown to be a major inducer of VEGF gene transcription. The tyrosine kinases Flt-1 (VEGFR-1) and Flk-1/KDR (VEGFR-2) are high-affinity VEGF receptors. The role of VEGF in developmental angiogenesis is emphasized by the finding that loss of a single VEGF allele results in defective vascularization and early embryonic lethality. VEGF is critical also for reproductive and bone angiogenesis. Substantial evidence also implicates VEGF as a mediator of pathological angiogenesis. In situ hybridization studies demonstrate expression of VEGF mRNA in the majority of human tumors. Anti-VEGF monoclonal antibodies and other VEGF inhibitors block the growth of several tumor cell lines in nude mice. Clinical trials with various VEGF inhibitors in a variety of malignancies are ongoing. Very recently, an anti-VEGF monoclonal antibody (bevacizumab; Avastin) has been approved by the Food and Drug Administration as a first-line treatment for metastatic colorectal cancer in combination with chemotherapy. Furthermore, VEGF is implicated in intraocular neovascularization associated with diabetic retinopathy and age-related macular degeneration.
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Affiliation(s)
- Napoleone Ferrara
- Department of Molecular Oncology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
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263
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He R, Liu B, Yang C, Yang RC, Tobelem G, Han ZC. Inhibition of K562 leukemia angiogenesis and growth by expression of antisense vascular endothelial growth factor (VEGF) sequence. Cancer Gene Ther 2004; 10:879-86. [PMID: 14712314 DOI: 10.1038/sj.cgt.7700645] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Vascular endothelial growth factor (VEGF), a major angiogenic factor, plays a key role in the growth of solid tumor. Recently, expression of VEGF and its receptors has been found on leukemic cells as well as on endothelial cells. VEGF may fulfill a fundamental role in promoting tumor angiogenesis and proliferation by stimulating both endothelial cells and leukemic cells. To investigate the role of VEGF in the angiogenesis and growth of leukemic cell, we used an antisense strategy to downregulate VEGF expression in K562 cells, a human erythroleukemia cell line. Expression of antisense-VEGF in K562 cells reduced the secretion of VEGF protein and inhibited cell survival. The proliferation and migration of human umbilical vein endothelial cells were decreased in response to the conditioned medium (CM) from K562 cells expressed antisense-VEGF, compared to CM from K562 cells transfected with vector control. Moreover, subcutaneous injection of nude mice with antisense-VEGF K562 cells inhibited tumor growth with a reduction of the density of microvessels and an increased apoptosis in those tumors, compared to vector control K562 cells. These results suggest that the efficient downregulation of the VEGF production in leukemic cells using antisense-VEGF may constitute a novel strategy of treatment in leukemia.
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Affiliation(s)
- Rui He
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Hospital of Blood Diseases, Chinese Academy of Medical Sciences & Peking Union of Medical College, Tianjin 300020, China
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264
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Abstract
Haematopoiesis is controlled by a number of growth factors and cytokines, a number of which act through binding to high-affinity receptor tyrosine kinases (RTKs). Approximately 20 different RTK classes have been identified, all of which share a similar structure that includes a ligand binding extracellular domain, a single transmembrane domain and an intracellular tyrosine kinase domain. Recent studies have linked an increasing number of mutations in the RTKs to the pathogenesis of both acute and chronic leukaemia. For example, the FLT3 receptor, a RTK class III, is the most commonly mutated gene in acute myeloid leukaemia, while c-kit mutations are strongly linked to the development of mast cell malignancy. This review summarizes the RTK classes that are known to be expressed on normal haematopoietic tissue and highlights the many 'gain-of-function' mutations involved in leukaemogenesis. It is to be hoped that this knowledge will provide important new insights for targeted therapy in leukaemia.
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265
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Wang ES, Teruya-Feldstein J, Wu Y, Zhu Z, Hicklin DJ, Moore MAS. Targeting autocrine and paracrine VEGF receptor pathways inhibits human lymphoma xenografts in vivo. Blood 2004; 104:2893-902. [PMID: 15238424 DOI: 10.1182/blood-2004-01-0226] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The role of angiogenesis in lymphoproliferative diseases is not well established. We demonstrate here that human lymphoma cells secrete vascular endothelial growth factor (VEGF) and express VEGF receptor 1 (VEGFR-1) and VEGFR-2. Proliferation of non-Hodgkin lymphoma (NHL) cells under serum-free conditions was enhanced by the addition of VEGF and was blocked by VEGFR-1- and VEGFR-2-specific antibodies. To differentiate between VEGF-mediated autocrine and paracrine effects on lymphoma growth, NOD/SCID mice engrafted with human diffuse large B-cell lymphoma (DLBCL) were treated with species-specific antibodies against human VEGFR-1 (6.12), human VEGFR-2 (IMC-1C11), murine VEGFR-1 (MF-1), or murine VEGFR-2 (DC101). Treatment with 6.12 or DC101 (targeting tumor VEGFR-1 and host VEGFR-2) reduced established DLBCL xenograft growth, whereas treatment with IMC-1C11 or MF-1 (targeting tumor VEGFR-1 and host VEGFR-1) had no effect. Decreased tumor volumes after 6.12 and DC101 treatment correlated with increased tumor apoptosis and reduced vascularization, respectively, supporting the presence of autocrine VEGFR-1- and paracrine VEGFR-2-mediated pathways in lymphomagenesis. Inhibition of paracrine VEGF interactions (DC101) in these models was equivalent to their inhibition with rituximab. Combining DC101 with therapeutic agents (rituximab, 6.12, methotrexate) consistently improved tumor responses over those of single-agent therapy. These data support the further clinical development of VEGFR-targeted approaches for the therapy of aggressive DLBCL.
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MESH Headings
- Animals
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal/therapeutic use
- Antineoplastic Combined Chemotherapy Protocols/pharmacology
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Autocrine Communication/drug effects
- Autocrine Communication/physiology
- Cell Proliferation/drug effects
- Drug Delivery Systems
- Humans
- Lymphoma, Large B-Cell, Diffuse/drug therapy
- Lymphoma, Large B-Cell, Diffuse/pathology
- Lymphoma, Non-Hodgkin/drug therapy
- Lymphoma, Non-Hodgkin/pathology
- Mice
- Mice, SCID
- Neoplasm Transplantation
- Paracrine Communication/drug effects
- Paracrine Communication/physiology
- Receptors, Vascular Endothelial Growth Factor/immunology
- Receptors, Vascular Endothelial Growth Factor/metabolism
- Transplantation, Heterologous
- Vascular Endothelial Growth Factor Receptor-1/immunology
- Vascular Endothelial Growth Factor Receptor-1/metabolism
- Vascular Endothelial Growth Factor Receptor-2/immunology
- Vascular Endothelial Growth Factor Receptor-2/metabolism
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Affiliation(s)
- Eunice S Wang
- Laboratory of Developmental Hematopoiesis, Cell Biology Program, Department of Medicine, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY 10021, USA
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266
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Ruan GR, Liu YR, Chen SS, Fu JY, Chang Y, Qin YZ, Li JL, Yu H, Wang H. Effect of antisense VEGF cDNA transfection on the growth of chronic myeloid leukemia K562 cells in vitro and in nude mice. Leuk Res 2004; 28:763-9. [PMID: 15158098 DOI: 10.1016/j.leukres.2003.11.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2003] [Accepted: 11/25/2003] [Indexed: 11/16/2022]
Abstract
To further elucidate the role of vascular endothelial growth factor (VEGF) in the pathogenesis of chronic myeloid leukemia (CML), we transfected K562 cells with a VEGF(121)cDNA sense vector (S), an antisense (AS) vector or vector (V) alone. The growth of transfected cells was investigated by MTT and colony-formation assays, and apoptosis was measured by flow cytometry (FCM) of Annexin-V-FITC/PI dual labeled cells. Transfected cells were subcutaneously transplanted into nude mice and the microvessel density (MVD) of tumor masses was determined by vWF immunohistochemistry staining. We tested the supernatant of different transfected K562 cells against human bone marrow endothelial cells (BMECs), and examined the synergic effects of antisense VEGF(121)cDNA and IFNalpha or STI571 on the proliferation and apoptosis of K562 cells. We found that K562/AS transfectants exhibited a 49% reduction in VEGF secretion, whereas K562/S transfectants exhibited a 3-fold increase in VEGF secretion, all in comparison to the vector controls. K562 cells transfected with antisense VEGF(121)cDNA showed growth retardation in vitro. In transplanted nude mice in vivo, transfection of implanted cells with antisense VEGF(121)cDNA resulted in decreased tumor MVD, and increased apoptosis in the presence of IFNalpha. Taken together, these results suggest that VEGF may be involved in the pathogenesis of CML through autocrine and paracrine mechanisms, and that anti-VEGF therapy alone or in combination with conventional treatment may be beneficial for CML patients.
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Affiliation(s)
- Guo-Rui Ruan
- Institute of Hematology and People's Hospital, Peking University, 11 Xi-zhi-men South Street, Beijing 100044, China
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267
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O'Farrell AM, Yuen HA, Smolich B, Hannah AL, Louie SG, Hong W, Stopeck AT, Silverman LR, Lancet JE, Karp JE, Albitar M, Cherrington JM, Giles FJ. Effects of SU5416, a small molecule tyrosine kinase receptor inhibitor, on FLT3 expression and phosphorylation in patients with refractory acute myeloid leukemia. Leuk Res 2004; 28:679-89. [PMID: 15158089 DOI: 10.1016/j.leukres.2003.11.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2003] [Accepted: 11/13/2003] [Indexed: 11/29/2022]
Abstract
Acute myeloid leukemia (AML) is associated with dysregulated hematopoietic cell proliferation and increased bone marrow angiogenesis, each regulated by signaling through receptor tyrosine kinases (RTKs). SU5416 is a small molecule inhibitor of VEGF receptors, c-kit and FLT3 and therefore provides a novel opportunity to target both angiogenesis and proliferation in AML. SU5416 was assessed in a phase II hematological malignancy trial in the US, where partial responses were observed in two of 33 patients. Since AML provides a unique platform to evaluate mechanism of action of small molecule inhibitors, investigation of the effect of SU5416 on FLT3 expression and phosphorylation in blood and bone marrow was an additional focus of this trial. Phosphorylated FLT3 was detected by immunoprecipitation/Western analysis in peripheral blood samples from 17 of 22 patients, and seven exhibited strong inhibition of phosphorylation immediately following a 1h SU5416 infusion, demonstrating that SU5416 can modulate RTK phosphorylation in humans. Although no clear correlation with clinical response was observed, analysis of patient plasma drug levels suggested that a threshold SU5416 concentration of 15 microM was associated with FLT3 inhibition. This observation was supported by data from an ex vivo model where AML cells were spiked into human blood, established to mimic the clinical setting and enable more rigorous analysis of effect of SU5416. In addition, FLT3 protein levels were downregulated in patient bone marrow samples, analyzed by an RIA assay. To identify putative predictors of response, patient plasma was analyzed for levels of secreted ligands of SU5416 targets; SCF and FLT3 ligand. Baseline levels of SCF in patients with stable or progressive disease were significantly higher than those in normal donors, whereas FLT3 ligand levels in patients who exhibited progressive disease were significantly lower than those in normal donors. The translational and clinical analyses described in this report provide some insights into the mechanism and duration of action of SU5416.
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268
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List AF, Glinsmann-Gibson B, Stadheim C, Meuillet EJ, Bellamy W, Powis G. Vascular endothelial growth factor receptor-1 and receptor-2 initiate a phosphatidylinositide 3-kinase–dependent clonogenic response in acute myeloid leukemia cells. Exp Hematol 2004; 32:526-35. [PMID: 15183893 DOI: 10.1016/j.exphem.2004.03.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2003] [Revised: 01/02/2004] [Accepted: 03/12/2004] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Vascular endothelial growth factor (VEGF) interacts with two high-affinity receptor tyrosine kinases (RTK) on vascular endothelium to initiate complementary but disparate biologic responses. We previously reported that acute myeloid leukemia (AML) cells express VEGF and one or both VEGF-A receptors, Flt-1 (VEGFR-1) and KDR (VEGFR-2). To evaluate receptor-selective trophic response to VEGF-A in AML cells, we investigated receptor-specific ligand activation responsible for VEGF-initiated clonogenic response. MATERIALS AND METHODS Using KG1 (VEGFR-1+/VEGFR-2+) and HL60 (VEGFR-1+) cells with differential VEGF receptor display, we investigated ligand-induced clonogenic response and receptor-initiated signaling after stimulation with VEGF-A, the VEGFR-1 selective ligand placental growth factor (PlGF), or receptor-specific antibody agonists. RESULTS Recombinant human (rhu)-VEGF increased S-phase fraction and stimulated colony formation in both KG1 and HL60 cells. Ligation of VEGFR-1 or VEGFR-2 with receptor-specific antibody agonists triggered equivalent and concentration-dependent stimulation of colony recovery in KG1 cells, whereas clonogenic response in HL60 cells was restricted to VEGFR-1 activation by antibody or PlGF. In serum-deprived KG1 and HL60 cells, rhu-VEGF stimulated rapid and sustained phosphorylation of Akt/PKB that was inhibited by the phosphatidyl inositol 3-kinase (PI3-K) kinase inhibitor wortmannin. Preincubation with wortmannin inhibited VEGF-induced colony formation in a concentration-dependent fashion. rhu-VEGF-induced clonogenic response and Akt phosphorylation was abolished by the VEGF-RTK inhibitor SU-5416 at concentrations greater than 10 microM, whereas MEK inhibition by PD98059 (1 and 10 microM) was ineffective. In vivo suppression of Akt phosphorylation was confirmed in myeloblast lysates from three patients with advanced myeloid malignancies treated with SU5416. CONCLUSION These data indicate that VEGF interaction with either VEGFR-1 or VEGFR-2 initiates a clonogenic response in AML cells that is PI3-kinase dependent. RTK inhibitors with broad specificity for angiogenic receptors represent novel therapeutics that merit further clinical investigation in AML.
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Affiliation(s)
- Alan F List
- The H. Lee Moffitt Cancer Center & Research Institute, University of South Florida, Tampa, Fl. 33612, USA.
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269
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Karp JE, Gojo I, Pili R, Gocke CD, Greer J, Guo C, Qian D, Morris L, Tidwell M, Chen H, Zwiebel J. Targeting Vascular Endothelial Growth Factor for Relapsed and Refractory Adult Acute Myelogenous Leukemias. Clin Cancer Res 2004; 10:3577-85. [PMID: 15173063 DOI: 10.1158/1078-0432.ccr-03-0627] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Vascular endothelial growth factor (VEGF) promotes acute myelogenous leukemia (AML) cell growth and survival and may contribute to drug resistance. bevacizumab, an anti-VEGF monoclonal antibody, exhibits clinical activity against diverse malignancies when administered with cytotoxic chemotherapy. We conducted a Phase II clinical trial of bevacizumab administered after chemotherapy to adults with refractory or relapsed AML, using a timed sequential therapy (TST) approach. EXPERIMENTAL DESIGN bevacizumab 10 mg/kg was administered on day 8 after 1-beta-d-arabinofuranosylcytosine 2 g/m(2)/72 h beginning day 1 and mitoxantrone 40 mg/m(2) beginning day 4. In vivo laboratory correlates included AML cell VEGF receptor-1 (FLT-1) expression, marrow microvessel density, and free serum VEGF before and during TST with bevacizumab. RESULTS Forty-eight adults received induction therapy. Myelosuppression occurred in all of the patients similar to other TST regimens. Toxicities were decreased ejection fraction (6%), cerebrovascular bleed (4%), and mortality of 15%. Overall response was 23 of 48 (48%), with complete response (CR) in 16 (33%). Eighteen (14 CR and 4 partial response) underwent one consolidation cycle and 5 (3 CR and 2 partial response) underwent allogeneic transplant. Median overall and disease-free survivals for CR patients were 16.2 months (64%, 1 year) and 7 months (35%, 1 year). Marrow blasts demonstrated FLT-1 staining before bevacizumab and marked decrease in microvessel density after bevacizumab. VEGF was detected in pretreatment serum in 67% of patients tested, increased by day 8 in 52%, and decreased in 93% (67% undetectable) 2 h after bevacizumab. CONCLUSIONS In this single arm study, cytotoxic chemotherapy followed by bevacizumab yields a favorable CR rate and duration in adults with AML that is resistant to traditional treatment approaches. The clearance of marrow blasts in some patients after bevacizumab suggests that VEGF neutralization might result directly in leukemic cell death. The potential biological and clinical activity of bevacizumab in AML warrants additional clinical and laboratory study.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Antibodies, Monoclonal/chemistry
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Monoclonal, Humanized
- Antimetabolites, Antineoplastic/pharmacology
- Antineoplastic Agents/pharmacology
- Bevacizumab
- Cell Line, Tumor
- Cell Proliferation
- Cytarabine/therapeutic use
- Disease-Free Survival
- Drug Resistance, Neoplasm
- Enzyme-Linked Immunosorbent Assay
- Female
- Humans
- Immunohistochemistry
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, Myeloid, Acute/metabolism
- Male
- Microcirculation
- Middle Aged
- Mitoxantrone/therapeutic use
- Recombinant Proteins/chemistry
- Recurrence
- Time Factors
- Treatment Outcome
- Vascular Endothelial Growth Factor A/blood
- Vascular Endothelial Growth Factor A/chemistry
- Vascular Endothelial Growth Factor A/metabolism
- Vascular Endothelial Growth Factor Receptor-1/metabolism
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Affiliation(s)
- Judith E Karp
- University of Maryland Greenebaum Cancer Center, Baltimore, Maryland, USA.
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270
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Santos SCR, Dias S. Internal and external autocrine VEGF/KDR loops regulate survival of subsets of acute leukemia through distinct signaling pathways. Blood 2004; 103:3883-9. [PMID: 14726393 DOI: 10.1182/blood-2003-05-1634] [Citation(s) in RCA: 134] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Besides being expressed on endothelial cells, vascular endothelial growth factor receptors (VEGFRs) are also functional on subsets of leukemias, resulting in autocrine loops that sustain leukemia migration and proliferation. While recent evidence suggests that VEGF supports hematopoietic stem cell survival via an internal loop, the molecular mechanisms whereby autocrine stimulation of VEGFR-2 (KDR) promotes leukemia growth are not well understood. Here we show on acute myeloid primary leukemias and cell lines that VEGF/KDR autocrine loops operate both internally and externally. First, we demonstrate that KDR is constitutively phosphorylated and located at the nucleus of VEGF-producing leukemias. Treatment with anti-VEGF antibody, which acts externally, blocked KDR nuclear translocation and inhibited nuclear factor κ B (NF-κB; p65 and c-rel) activation. In contrast, a KDR-specific intracellular inhibitor failed to block KDR nuclear translocation, but inhibited the constitutive activation of mitogen activated protein kinase (MAPK)/Erk and the phosphatidylinositol 3-kinase/AKT pathways. Notably, treatment with the anti-VEGF antibody alone had little effect on cell survival, while the internal inhibitor induced leukemia apoptosis, and the 2 drugs produced synergistic effects, together and with chemotherapy, reducing cell survival to a larger extent than either agent alone. Our results demonstrate that internal and external VEGF/KDR autocrine loops regulate leukemia survival via different mechanisms, and suggest that blocking both may have therapeutic potential.
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271
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Molica S, Vacca A, Levato D, Merchionne F, Ribatti D. Angiogenesis in acute and chronic lymphocytic leukemia. Leuk Res 2004; 28:321-4. [PMID: 15109528 DOI: 10.1016/j.leukres.2003.08.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2003] [Accepted: 08/02/2003] [Indexed: 11/22/2022]
Abstract
The bone marrow microenvironment plays a crucial role in leukemogenesis. Recent studies suggest that its vascularity changes significantly during this process and that angiogenic factors are of major importance in leukemia. This review summarizes the literature concerning the relationship between angiogenesis and the progression of acute and chronic lymphocytic leukemia. It is becoming increasingly evident that agents which interfere with angiogenesis also block tumor progression and anti-angiogenic management has become a prominent aspect of pre-clinical and clinical assessment. Recent applications of anti-angiogenic agents which interfere with or block leukemia progression are reviewed.
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Affiliation(s)
- Stefano Molica
- Department of Medical Oncology, Azienda Ospedaliera Pugliese-Ciaccio, Viale Pio X, 88100 Catanzaro, Italy.
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272
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Lee YK, Bone ND, Strege AK, Shanafelt TD, Jelinek DF, Kay NE. VEGF receptor phosphorylation status and apoptosis is modulated by a green tea component, epigallocatechin-3-gallate (EGCG), in B-cell chronic lymphocytic leukemia. Blood 2004; 104:788-94. [PMID: 14996703 DOI: 10.1182/blood-2003-08-2763] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
We recently reported that chronic lymphocytic leukemia (CLL) cells synthesize and release vascular endothelial growth factor (VEGF) under normoxic and hypoxic conditions. CLL B cells also express VEGF membrane receptors (VEGF-R1 and VEGF-R2), suggesting that they use VEGF as a survival factor. To assess the mechanism of apoptosis resistance related to VEGF, we determined the impact of VEGF on CLL B cells, and we studied the impact of epigallocatechin-3-gallate (EGCG), a known receptor tyrosine kinase (RTK) inhibitor, on VEGF receptor status and viability of CLL B cells. VEGF165 significantly increased apoptotic resistance of CLL B cells, and immunoblotting revealed that VEGF-R1 and VEGF-R2 are spontaneously phosphorylated on CLL B cells. EGCG significantly increased apoptosis/cell death in 8 of 10 CLL samples measured by annexin V/propidium iodide (PI) staining. The increase in annexin V/PI staining was accompanied by caspase-3 activation and poly-adenosine diphosphate ribose polymerase (PARP) cleavage at low concentrations of EGCG (3 microg/mL). Moreover, EGCG suppressed the proteins B-cell leukemia/lymphoma-2 protein (Bcl-2), X-linked inhibitor of apoptosis protein (XIAP), and myeloid cell leukemia-1 (Mcl-1) in CLL B cells. Finally, EGCG (3-25 microg/mL) suppressed VEGF-R1 and VEGF-R2 phosphorylation, albeit incompletely. Thus, these results suggest that VEGF signaling regulates survival signals in CLL cells and that interruption of this autocrine pathway results in caspase activation and subsequent leukemic cell death.
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MESH Headings
- Antineoplastic Agents, Phytogenic/pharmacology
- Apoptosis/physiology
- B-Lymphocytes/immunology
- Catechin/analogs & derivatives
- Catechin/pharmacology
- Cell Survival/drug effects
- Gene Expression Regulation, Neoplastic/genetics
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/blood
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Phosphorylation
- Reference Values
- Reverse Transcriptase Polymerase Chain Reaction
- Tumor Cells, Cultured
- Vascular Endothelial Growth Factor Receptor-1/drug effects
- Vascular Endothelial Growth Factor Receptor-1/genetics
- Vascular Endothelial Growth Factor Receptor-1/physiology
- Vascular Endothelial Growth Factor Receptor-2/drug effects
- Vascular Endothelial Growth Factor Receptor-2/genetics
- Vascular Endothelial Growth Factor Receptor-2/physiology
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Affiliation(s)
- Yean K Lee
- Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA
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273
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Owen JL, Iragavarapu-Charyulu V, Gunja-Smith Z, Herbert LM, Grosso JF, Lopez DM. Up-regulation of matrix metalloproteinase-9 in T lymphocytes of mammary tumor bearers: role of vascular endothelial growth factor. THE JOURNAL OF IMMUNOLOGY 2004; 171:4340-51. [PMID: 14530359 DOI: 10.4049/jimmunol.171.8.4340] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Matrix metalloproteinase-9 (MMP-9), a matrix-degrading enzyme, is crucial in tumor invasion and metastasis and is implicated in leukocyte extravasation. In this report, we demonstrate that during growth of the D1-7,12-dimethylbenzanthracene-3 mammary tumor in BALB/c mice, there is progressive up-regulation of MMP-9 in splenic T cells at both the transcriptional and translational levels. Our previous work has identified several factors produced by this tumor, including PGE(2), GM-CSF, and phosphatidyl serine; however, none of these agents induces increased production of MMP-9 by normal splenic T cells. Although not produced by the tumor, TNF-alpha and IL-6 are up-regulated in both macrophages and B cells in tumor-bearing mice. Exposure of normal T cells to these two cytokines, however, also fails to up-regulate MMP-9 production. Vascular endothelial growth factor (VEGF) is produced by many tumors, and we determined that the mammary tumor used in our studies expresses high levels of this angiogenic growth factor. Importantly, splenic T cells from tumor bearers constitutively produce increased amounts of VEGF, and treatment of normal T cells with VEGF results in up-regulated MMP-9 production. Of crucial importance is the finding that tumor-infiltrating T cells also produce high levels of VEGF and MMP-9. Our studies indicate that VEGF can act directly on T lymphocytes and that elevated VEGF levels may contribute to the aberrant MMP-9 secretion by mammary tumor bearers' T cells.
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Affiliation(s)
- Jennifer L Owen
- Department of Microbiology, University of Miami School of Medicine, Miami, FL 33101, USA
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274
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Ludwig DL, Pereira DS, Zhu Z, Hicklin DJ, Bohlen P. Monoclonal antibody therapeutics and apoptosis. Oncogene 2003; 22:9097-106. [PMID: 14663488 DOI: 10.1038/sj.onc.1207104] [Citation(s) in RCA: 238] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The potential for disease-specific targeting and low toxicity profiles have made monoclonal antibodies attractive therapeutic drug candidates. Antibody-mediated target cell killing is frequently associated with immune effector mechanisms such as antibody-directed cellular cytotoxicity, but they can also be induced by apoptotic processes. Antibody-directed mechanisms, including antigen crosslinking, activation of death receptors, and blockade of ligand-receptor growth or survival pathways, can elicit the induction of apoptosis in targeted cells. Depending on their mechanism of action, monoclonal antibodies can induce targeted cell-specific killing alone or can enhance target cell susceptibility to chemo- or radiotherapeutics by effecting the modulation of antiapoptotic pathways. This review will focus on the mechanisms by which antibodies are capable of eliciting programmed cell death either directly or indirectly within tumor cells.
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Affiliation(s)
- Dale L Ludwig
- ImClone Systems Incorporated, 180 Varick Street, New York, NY 10014, USA.
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275
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Lancet JE, Karp JE. Farnesyltransferase inhibitors in hematologic malignancies: new horizons in therapy. Blood 2003; 102:3880-9. [PMID: 12920034 DOI: 10.1182/blood-2003-02-0633] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Farnesyltransferase inhibitors (FTIs) are small-molecule inhibitors that selectively inhibit farnesylation of a number of intracellular substrate proteins such as Ras. Preclinical work has revealed their ability to effectively inhibit tumor growth across a wide range of malignant phenotypes. Many hematologic malignancies appear to be reasonable disease targets, in that they express relevant biologic targets, such as Ras, mitogen-activated protein kinase (MAPK), AKT, and others that may depend on farnesyl protein transferase (FTase) activity to promote proliferation and survival. A host of phase 1 trials have been recently launched to assess the applicability of FTIs in hematologic malignancies, many of which demonstrate effective enzyme target inhibition, low toxicity, and some clinical responses. As a result, phase 2 trials have been initiated in a variety of hematologic malignancies and disease settings to further validate clinical activity and to identify downstream signal transduction targets that may be modified by these agents. It is anticipated that these studies will serve to define the optimal roles of FTIs in patients with hematologic malignancies and provide insight into effective methods by which to combine FTIs with other agents.
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Affiliation(s)
- Jeffrey E Lancet
- James P. Wilmot Cancer Center, University of Rochester, 601 Elmwood Ave, Box 704, Rochester, NY 14642, USA.
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276
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Maru Y. Tyrosine kinase as molecular target of anti-tumor drug. Nihon Yakurigaku Zasshi 2003; 122:473-81. [PMID: 14639001 DOI: 10.1254/fpj.122.473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Tyrosine kinase (TK) plays an important role in a variety of biological circumstances including growth, apoptosis, differentiation, immune system, angiogenesis, development, and so forth. Some inhibitors for TK have been successful in clinical applications in malignant disorders. Due to its physiological participation in cells exposed to many stimuli and to structural homology of high degree, true molecular targeting requires complete understanding of signal transduction pathways in all of the cells in which the targeted TK is involved.
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Affiliation(s)
- Yoshiro Maru
- Department of Pharmacology, Tokyo Women's Medical University, Japan
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277
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Lu D, Shen J, Vil MD, Zhang H, Jimenez X, Bohlen P, Witte L, Zhu Z. Tailoring in vitro selection for a picomolar affinity human antibody directed against vascular endothelial growth factor receptor 2 for enhanced neutralizing activity. J Biol Chem 2003; 278:43496-507. [PMID: 12917408 DOI: 10.1074/jbc.m307742200] [Citation(s) in RCA: 153] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) and its receptors have been implicated in promoting solid tumor growth and metastasis via stimulating tumor-associated angiogenesis. We previously identified several fully human neutralizing anti-VEGF receptor 2 (or kinase inserting domain-containing receptor (KDR)) antibodies from a large antibody phage display library. These antibodies bind specifically to KDR, block VEGF/KDR interaction, and inhibit VEGF-induced proliferation of human endothelial cells and migration of KDR+ leukemia cells. Three of these antibodies, interestingly, share an identical heavy chain variable (VH) sequence. In this report, we constructed a new library comprising the single VH paired with the variable light chain (VL) repertoire obtained from the original naïve human library. Initial in vitro selection revealed that the single VH could pair with a number of different VL while retaining its specificity for KDR. However, a consensus VH/VL pair, clone 1121, was identified after three or four rounds of selection by tailoring the stringency of the panning conditions. Clone 1121 showed a >30-fold higher binding affinity to KDR (Kd, 100 pm) because of improvement on both association and dissociation constants and blocked VEGF/KDR interaction with an IC50 of approximately 1 nm, compared with that of 3-4 nm for the parent Fab fragments. Further, clone 1121 was more potent in inhibiting VEGF-stimulated KDR phosphorylation in endothelial cells. A binding epitope mapping study on clone 1121 and one of the parent clones, 2C6, demonstrated that both antibodies interacted with the third immunoglobulin domain within the extracellular region of KDR. Several peptide phage display libraries were utilized to further examine the fine binding specificities of the two antibodies. All of the 2C6-binding peptides are cysteine-constrained, whereas clone 1121 binds to both cysteine-constrained and linear peptides. It is noteworthy that most of the 2C6-binding peptides also cross-react with clone 1121, but none of the clone 1121-specific peptides binds to 2C6, indicating that clone 1121 retained part of the original binding epitope(s) of 2C6 while gaining new binding specificity. Taken together, our observation suggests that clone 1121 may have great clinical potential in anti-angiogenesis therapy. It further underscores the efforts to identify antibodies of high affinity for enhanced biological activities.
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Affiliation(s)
- Dan Lu
- Departments of Antibody Technology, Molecular and Cell Biology, and Research, ImClone Systems Incorporated, New York, New York 10014, USA
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278
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Liu JY, Wei YQ, Yang L, Zhao X, Tian L, Hou JM, Niu T, Liu F, Jiang Y, Hu B, Wu Y, Su JM, Lou YY, He QM, Wen YJ, Yang JL, Kan B, Mao YQ, Luo F, Peng F. Immunotherapy of tumors with vaccine based on quail homologous vascular endothelial growth factor receptor-2. Blood 2003; 102:1815-23. [PMID: 12750177 DOI: 10.1182/blood-2002-12-3772] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The breaking of immune tolerance of "self-antigens" associated with angiogenesis is an attractive approach to cancer therapy by active immunity. We used vascular endothelial growth factor receptor-2 (VEGFR-2) as a model antigen to explore the feasibility of the immunotherapy with a vaccine based on a xenogeneic homologous protein. To test this concept, we prepared a quail homologous VEGFR-2 protein vaccine (qVEGFR) based on quail VEGFR-2. At the same time, a protein vaccine based on the corresponding ligand-binding domain of mouse self-VEGFR-2 (mVEGFR) was also prepared and used as a control. We found that immunotherapy with qVEGFR was effective at protective and therapeutic antitumor immunity in several solid and hematopoietic tumor models in mice. Autoantibodies against mouse VEGFR-2 (Flk-1) were identified by Western blot analysis and enzyme-linked immunosorbent assay (ELISA). Anti-VEGFR antibody-producing B cells were detectable by ELISPOT. Endothelial deposition of immunoglobulins developed within tumor. VEGF-mediated endothelial cell proliferation was inhibited in vitro by immunoglobulins from qVEGFR-immunized mice. Antitumor activity was caused by the adoptive transfer of the purified immunoglobulins. Antitumor activity and production of autoantibodies against Flk-1 could be abrogated by the depletion of CD4+ T lymphocytes. Angiogenesis was apparently inhibited within the tumors, and the vascularization of alginate beads was also reduced. No marked toxicity was found in the immunized mice. The observations may provide a vaccine strategy for cancer therapy through the induction of autoimmunity against the growth factor receptor associated with angiogenesis in a cross-reaction with single xenogeneic homologous protein.
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Affiliation(s)
- Ji-Yan Liu
- Key Laboratory of Biotherapy of Human Diseases and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Guo Xue Xiang, No. 37, Chengdu, Sichuan, 610041, The People's Republic of China
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279
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Giles FJ, Stopeck AT, Silverman LR, Lancet JE, Cooper MA, Hannah AL, Cherrington JM, O'Farrell AM, Yuen HA, Louie SG, Hong W, Cortes JE, Verstovsek S, Albitar M, O'Brien SM, Kantarjian HM, Karp JE. SU5416, a small molecule tyrosine kinase receptor inhibitor, has biologic activity in patients with refractory acute myeloid leukemia or myelodysplastic syndromes. Blood 2003; 102:795-801. [PMID: 12649163 DOI: 10.1182/blood-2002-10-3023] [Citation(s) in RCA: 156] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Increased bone marrow angiogenesis and vascular endothelial growth factor (VEGF) levels are adverse prognostic features in patients with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDSs). VEGF is a soluble circulating angiogenic molecule that stimulates signaling via receptor tyrosine kinases (RTKs), including VEGF receptor 2 (VEGFR-2). AML blasts may express VEGFR-2, c-kit, and FLT3. SU5416 is a small molecule RTK inhibitor (RTKI) of VEGFR-2, c-kit, and both wild-type and mutant FLT3. A multicenter phase 2 study of SU5416 was conducted in patients with refractory AML or MDS. For a median of 9 weeks (range, 1-55 weeks), 55 patients (33 AML: 10 [30%] primary refractory, 23 [70%] relapsed; 22 MDS: 15 [68%] relapsed) received 145 mg/m2 SU5416 twice weekly intravenously. Grade 3 or 4 drug-related toxicities included headaches (14%), infusion-related reactions (11%), dyspnea (14%), fatigue (7%), thrombotic episodes (7%), bone pain (5%), and gastrointestinal disturbance (4%). There were 11 patients (20%) who did not complete 4 weeks of therapy (10 progressive disease, 1 adverse event); 3 patients (5%) who achieved partial responses; and 1 (2%) who achieved hematologic improvement. Single agent SU5416 had biologic and modest clinical activity in refractory AML/MDS. Overall median survival was 12 weeks in AML patients (range, 4-41 weeks) and not reached in MDS patients. Most observed toxicities were attributable to drug formulation (polyoxyl 35 castor oil or hyperosmolarity of the SU5416 preparation). Studies of other RTKI and/or other antiangiogenic approaches, with correlative studies to examine biologic effects, may be warranted in patients with AML/MDS.
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Affiliation(s)
- Francis J Giles
- Department of Leukemia, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Box 428, Houston, TX 77030, USA.
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280
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281
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Abstract
Vascular endothelial growth factor (VEGF) is a key regulator of physiological angiogenesis during embryogenesis, skeletal growth and reproductive functions. VEGF has also been implicated in pathological angiogenesis associated with tumors, intraocular neovascular disorders and other conditions. The biological effects of VEGF are mediated by two receptor tyrosine kinases (RTKs), VEGFR-1 and VEGFR-2, which differ considerably in signaling properties. Non-signaling co-receptors also modulate VEGF RTK signaling. Currently, several VEGF inhibitors are undergoing clinical testing in several malignancies. VEGF inhibition is also being tested as a strategy for the prevention of angiogenesis, vascular leakage and visual loss in age-related macular degeneration.
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Affiliation(s)
- Napoleone Ferrara
- Department of Molecular Oncology, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, USA.
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282
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Wu W, Shu X, Hovsepyan H, Mosteller RD, Broek D. VEGF receptor expression and signaling in human bladder tumors. Oncogene 2003; 22:3361-70. [PMID: 12776187 DOI: 10.1038/sj.onc.1206285] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Overexpression of vascular endothelial growth factor receptors (VEGFRs) has been reported in a variety of tumor types. Here we find that 11 out of the 14 bladder tumor cell lines examined express one or more VEGF receptors. Analysis of the T24 bladder tumor cell line reveals a functional autocrine loop involving VEGF and the Flk-1 receptor. Blocking VEGF expression in T24 cells results in a decrease in DNA synthesis. The Flk-1 receptor in T24 cells is phosphorylated in response to VEGF-121 or VEGF-165, and an Flk-1 inhibitor blocks VEGF to ERK signaling. We report that VEGF stimulation of T24 cells results in activation of H- and N-Ras and this is dependent on cellular sphingosine kinase 1 (SPK1) activity. Previously, we found VEGF-induced activation of Ras appears to be independent of a Ras-guanine nucleotide exchange factors (GEFs). Here we report that sphingosine can stimulate Ras-GTPase activating protein (GAP) activity in vitro, and sphingosine-1-phosphate (SPP) can block the stimulatory effects of sphingosine. We present a model where the balance between sphingosine and SPP regulates Ras-GAP activity such that stimulation of SPK1 favors downregulation of Ras-GAP and thereby the activation of Ras proteins. These data highlight a VEGF pathway that may be involved in the survival and proliferation of bladder tumor cells as well as other tumor cell types.
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Affiliation(s)
- Weicheng Wu
- Department of Biochemistry and Molecular Biology, Norris Comprehensive Cancer Center, Keck School of Medicine at the University of Southern California, CA 90089, USA
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283
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Hu YL, Albanese C, Pestell RG, Jaffe RB. Dual mechanisms for lysophosphatidic acid stimulation of human ovarian carcinoma cells. J Natl Cancer Inst 2003; 95:733-40. [PMID: 12759391 DOI: 10.1093/jnci/95.10.733] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Lysophosphatidic acid (LPA), at concentrations present in ascitic fluid, indirectly stimulates the growth of malignant ovarian tumors by increasing the expression of vascular endothelial growth factor (VEGF) in ovarian cancer cells. We investigated whether LPA could also directly promote ovarian tumor growth by increasing the level of cyclin D1, a key G1-phase checkpoint regulator, which thereby increases cell proliferation. METHODS Expression of cyclin D1 and LPA receptors (EDG4 and EDG7) was determined in six ovarian cancer cell lines (including OVCAR-3 cells) and immortalized ovarian surface epithelial cells (IOSE-29). Cyclin D1 promoter activity was measured in LPA-treated OVCAR-3 cells cotransfected with cyclin D1 promoter-driven luciferase constructs and cDNA expression plasmids for IkappaBalphaM (a nuclear factor kappaB [NFkappaB] super-repressor). RESULTS Four of six cancer cell lines, including OVCAR-3, overexpressed cyclin D1 protein relative to levels in IOSE-29 cells. LPA treatment increased cyclin D1 protein in a dose- and time-dependent manner in OVCAR-3 cells but not in IOSE-29 cells. LPA stimulated cyclin D1 promoter activity (3.0-fold, 95% confidence interval [CI] = 2.7-fold to 3.3-fold). Mutation of the NFkappaB-binding site in the cyclin D1 promoter to block NFkappaB binding and expression of IkappaBalphaM, which binds NFkappaB and inhibits its binding to the promoter, markedly diminished LPA stimulation of cyclin D1 promoter activity (activity stimulated only 1.4-fold, 95% CI = 1.1-fold to 1.7-fold, and 0.7-fold, 95% CI = 0.6-fold to 0.8-fold, respectively). EDG4 was overexpressed in all cancer cell lines studied relative to that in IOSE-29 cells, but EDG7 was overexpressed in only two lines. CONCLUSIONS Dual mechanisms are probably involved in LPA stimulation of ovarian tumor growth in vivo. In addition to the previously characterized indirect mechanism that increases angiogenesis via VEGF, LPA may directly increase the level of cyclin D1 in ovarian cancer cells, increasing their proliferation.
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MESH Headings
- Blotting, Northern
- Blotting, Western
- Carcinoma/metabolism
- Cell Division/drug effects
- Cyclin D1/drug effects
- Cyclin D1/genetics
- Cyclin D1/metabolism
- Dose-Response Relationship, Drug
- Female
- Gene Expression Regulation, Neoplastic/drug effects
- Humans
- I-kappa B Proteins/genetics
- Luciferases/metabolism
- Lysophospholipids/metabolism
- Lysophospholipids/pharmacology
- Mutation
- NF-kappa B/genetics
- Ovarian Neoplasms/metabolism
- Promoter Regions, Genetic/drug effects
- RNA, Messenger/metabolism
- RNA, Neoplasm/metabolism
- Receptors, Cell Surface/metabolism
- Receptors, G-Protein-Coupled
- Receptors, Lysophosphatidic Acid
- Receptors, Vascular Endothelial Growth Factor/metabolism
- Serum Response Element/drug effects
- Time Factors
- Transfection
- Tumor Cells, Cultured
- Up-Regulation/drug effects
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Affiliation(s)
- Yu-Long Hu
- Center for Reproductive Sciences, University of California, San Francisco, CA 94143-0556, USA
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284
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Glade-Bender J, Kandel JJ, Yamashiro DJ. VEGF blocking therapy in the treatment of cancer. Expert Opin Biol Ther 2003; 3:263-76. [PMID: 12662141 DOI: 10.1517/14712598.3.2.263] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
It is widely accepted that tumour growth beyond a few cubic millimetres cannot occur without the induction of a new vascular supply. Inhibiting the development of new blood vessels (antiangiogenesis) is a potential approach to cancer therapy that has attracted interest in recent years. In theory, this approach should be relatively selective for tumour cells. The endothelial cells which form new vascular networks in tumours are responding to angiogenic stimuli produced by the tumour, but are themselves genetically normal. Endothelium in normal tissue, by contrast, is usually quiescent. Vascular endothelial growth factor (VEGF) is the best-characterised pro-angiogenic factor. It is virtually ubiquitous in human tumours, and higher levels have been correlated with more aggressive disease. Effective blockade of the VEGF pathway has been demonstrated with multiple agents: neutralising antibody, receptor tyrosine kinase inhibitors, and ribozyme or antisense molecules targeting expression. Promising preclinical data document the potential of these agents for tumour growth inhibition and even tumour regression, yet translation of novel therapeutics targeting the VEGF pathway to the clinic has proved a substantial challenge in itself. While showing clear evidence of antitumour activity over a broad spectrum of experimental tumours, the proper selection, dose, timing and sequence of anti-VEGF treatment in human cancer is not at all obvious. Classic Phase I dose escalation trial design may need to be modified, as higher doses may not be optimal in all patients or for all tumours. In addition, alternate or secondary biological end points (e.g., non-progression) may be needed for early phase studies to document true activity, so as not to abandon effective agents. Recent studies of the neutralising antibody bevacizumab, and small molecule tyrosine kinase inhibitor SU5416, demonstrate that, while unlikely to be effective as monotherapy, incorporation of VEGF blockade into cytotoxic regimens may increase overall response rates. However, incorporation may also produce new toxicities, including thromboembolic complications and bleeding. Newer oral agents, such as SU6668, SU11248, PTK787/ZK222584 and ZD6474, are particularly interesting for their potential for chronic therapy. Future clinical trials are likely to build on past experience with stricter entry criteria, supportive care guidelines and the use of surrogate markers.
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Affiliation(s)
- Julia Glade-Bender
- Division of Pediatric Surgery, College of Physicians and Surgeons at Columbia University, New York, NY 10032, USA
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285
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286
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Zhu Z, Hattori K, Zhang H, Jimenez X, Ludwig DL, Dias S, Kussie P, Koo H, Kim HJ, Lu D, Liu M, Tejada R, Friedrich M, Bohlen P, Witte L, Rafii S. Inhibition of human leukemia in an animal model with human antibodies directed against vascular endothelial growth factor receptor 2. Correlation between antibody affinity and biological activity. Leukemia 2003; 17:604-11. [PMID: 12646950 DOI: 10.1038/sj.leu.2402831] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Vascular endothelial growth factor (VEGF) and its receptors (VEGFR) have been implicated in promoting solid tumor growth and metastasis via stimulating tumor-associated angiogenesis. We recently showed that certain 'liquid' tumors such as leukemia not only produce VEGF, but also express functional VEGFR, resulting in an autocrine loop for tumor growth and propagation. A chimeric anti-VEGFR2 (or kinase insert domain-containing receptor, KDR) antibody, IMC-1C11, was shown to be able to inhibit VEGF-induced proliferation of human leukemia cells in vitro, and to prolong survival of nonobese diabetic-severe combined immune deficient (NOD-SCID) mice inoculated with human leukemia cells. Here we produced two fully human anti-KDR antibodies (IgG1), IMC-2C6 and IMC-1121, from Fab fragments originally isolated from a large antibody phage display library. These antibodies bind specifically to KDR with high affinities: 50 and 200 pM for IMC-1121 and IMC-2C6, respectively, as compared to 270 pM for IMC-1C11. Like IMC-1C11, both human antibodies block VEGF/KDR interaction with an IC(50) of approximately 1 nM, but IMC-1121 is a more potent inhibitor to VEGF-stimulated proliferation of human endothelial cells. These anti-KDR antibodies strongly inhibited VEGF-induced migration of human leukemia cells in vitro, and when administered in vivo, significantly prolonged survival of NOD-SCID mice inoculated with human leukemia cells. It is noteworthy that the mice treated with antibody of the highest affinity, IMC-1121, survived the longest period of time, followed by mice treated with IMC-2C6 and IMC-1C11. Taken together, our data suggest that anti-KDR antibodies may have broad applications in the treatment of both solid tumors and leukemia. It further underscores the efforts to identify antibodies of high affinity for enhanced antiangiogenic and antitumor activities.
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Affiliation(s)
- Z Zhu
- Department of Antibody Technology, ImClone Systems Incorporated, New York, NY 10014, USA
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287
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Moehler TM, Ho AD, Goldschmidt H, Barlogie B. Angiogenesis in hematologic malignancies. Crit Rev Oncol Hematol 2003; 45:227-44. [PMID: 12633837 DOI: 10.1016/s1040-8428(02)00135-x] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Angiogenesis is defined as the formation of new capillaries from preexisting blood vessels and plays an important role in the progression of solid tumors. Recently a similar relationship has been described in several hematologic malignancies. Expression of the angiogenic peptides vascular endothelial growth factor (VEGF) and basic fibroblast growth factor correlates with clinical characteristics in leukemia and non-Hodgkin's-lymphoma and the serum/plasma concentrations serve as predictors of poor prognosis. Increased bone marrow microvessels in multiple myeloma (MM) are correlated with decreased overall survival. Thalidomide which has antiangiogenic effects and direct cytotoxic effects was found to be effective in MM, myelodysplastic syndrome and acute myeloid leukemia (AML). Preliminary data indicate activity of VEGF-tyrosine kinase inhibitors in AML. Clinical research is now aimed at testing antiangiogenic treatment strategies in several hematologic neoplasms as well as identifying the best candidate patients for specific approaches.
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Affiliation(s)
- T M Moehler
- Department of Internal Medicine V, University of Heidelberg, Heidelberg, Germany
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288
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Ribatti D, Vacca A, Dammacco F, English D. Angiogenesis and anti-angiogenesis in hematological malignancies. JOURNAL OF HEMATOTHERAPY & STEM CELL RESEARCH 2003; 12:11-22. [PMID: 12662432 DOI: 10.1089/152581603321210091] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Although it is well established that the growth of solid tumors requires vigorous neovascularization, it has been assumed that leukemias and other hematological malignancies do not depend on angiogenesis. However, the role of angiogenesis in growth and survival of neoplastic cells of the hematopoietic system has recently been recognized, and provides a rationale for novel therapeutic approaches to hematological malignancy. This review summarizes the literature concerning the relationship between angiogenesis and disease progression of several hematological malignancies. It is becoming increasingly evident that agents that interfere with blood vessel formation also block tumor progression, and, accordingly, antiangiogenic therapy has gained much interest as a potential adjunct to conventional therapy of many hematological malignancies. Recent successful applications of antiangiogenic agents that interfere or block the progression of hematological malignancies are evaluated in light of recent demonstrations of potent angiogenic activity of several hematopoietic growth factors. A novel finding regarding the role of angiogenesis in hematological malignancies, which accounts for many clinical observations as well as the apparent independence of these tumors on marrow vascularity, is presented. The information presented in this review will facilitate the design of future clinical trials using antiangiogenic agents for the treatment of hematological malignancies and will provide a basis for the design of experiments undertaken to define the mechanisms involved, mechanisms that may shed new light on the pathology of hematological malignancies.
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Affiliation(s)
- Domenico Ribatti
- Department of Human Anatomy and Histology, University of Bari Medical School, I-70124 Bari, Italy.
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289
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Aguayo A, Giles F, Albitar M. Vascularity, angiogenesis and angiogenic factors in leukemias and myelodysplastic syndromes. Leuk Lymphoma 2003; 44:213-22. [PMID: 12688336 DOI: 10.1080/1042819021000029777] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Bone marrow microenvironment plays a crucial role inthe leukemogenic process. New studies suggest that the bone marrow vascularity changes significantly in the leukemic process and that angiogenic factors play a major role in leukemia and myelodysplasia. However, hematologic malignancies appear to be particularly vulnerable to the effects of angiogenic factors because most of these factors appear to be secreted by hematopoietic cells, and they may have autocrine and paracrine regulatory effects on the hematopoietic system. The use of angiogenesis inhibitors for the treatment of hematologic malignancies is particularly attractive because it may target not only the environment but also the malignant cells.
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Affiliation(s)
- Alvaro Aguayo
- Department of Blood and Marrow Transplantation, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
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290
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Hotz HG, Hines OJ, Hotz B, Foitzik T, Buhr HJ, Reber HA. Evaluation of vascular endothelial growth factor blockade and matrix metalloproteinase inhibition as a combination therapy for experimental human pancreatic cancer. J Gastrointest Surg 2003; 7:220-7; discussion 227-8. [PMID: 12600446 DOI: 10.1016/s1091-255x(02)00157-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Blockade of vascular endothelial growth factor (VEGF) and inhibition of matrix metalloproteinases (MMP) are promising therapies for cancer. This study assessed the effects of a neutralizing anti-VEGF antibody (A4.6.1) and an MMP inhibitor (BB-94) on pancreatic cancer (PaCa) in vivo. Five million cells of two human PaCa cell lines (AsPC-1 and HPAF-2) were injected subcutaneously into nude mice; 1 mm(3) fragments of the resulting tumors were implanted into the pancreas of other mice. Animals were randomized into a control group and three treatment groups: A4.6.1 (100 microg intraperitoneally twice weekly); BB-94 (50 mg/kg every other day); and combination (A4.6.1 plus BB-94). Treatment was started after 3 days and continued for 14 weeks. Tumor volume, local and distant spread (score), and ascites were determined at autopsy. Microvessel density as a parameter of neoangiogenesis was analyzed in CD31-stained tumor sections. Both monotherapies reduced tumor volume (HPAF-2: -89% by A4.6.1 and -75% by BB-94; AsPC-1: -48% by A4.6.1 and -72% by BB-94), spread (HPAF-2: -76% by A4.6.1 and -58% by BB-94; AsPC-1: -32% by A4.6.1 and -54% by BB-94), and microvessel density (HPAF-2: -75% by A4.6.1 and -30% by BB-94; AsPC-1: -59% by A4.6.1 and -30% by BB-94), resulting in a tendency toward increased survival (HPAF-2: 8 of 8 animals by A4.6.1 or BB-94 vs. 4 of 8; AsPC-1: 3 of 8 by A4.6.1, 4 of 8 by BB-94 vs. 1 of 8). Combination therapy yielded additional effects in the HPAF-2 group with regard to tumor volume (-95%) and development of ascites (0 of 8 vs. 2 of 8 by A4.6.1 or BB-94 vs. 5 of 8 control mice). Both VEGF blockade and MMP inhibition reduce primary tumor size, metastasis, and angiogenesis, thereby increasing survival in experimental pancreatic cancer. Combination treatment results in additive effects in moderately differentiated HPAF-2 tumors.
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Affiliation(s)
- Hubert G Hotz
- Department of Surgery, UCLA School of Medicine, Los Angeles, CA, USA
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291
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Gerber HP, Ferrara N. The role of VEGF in normal and neoplastic hematopoiesis. J Mol Med (Berl) 2003; 81:20-31. [PMID: 12545246 DOI: 10.1007/s00109-002-0397-4] [Citation(s) in RCA: 152] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2002] [Accepted: 10/15/2002] [Indexed: 02/07/2023]
Abstract
VEGF is a secreted growth factor that mediates its biological effects by binding to two transmembrane tyrosine kinase receptors, VEGFR-1 and VEGFR-2. The VEGF/receptor signaling system is involved in the regulation of two fundamental processes in vertebrates: the formation of blood vessels (angiogenesis) and of blood cells (hematopoiesis). Hematopoietic stem cells, capable of giving rise to all blood cell lineages, are often found in clusters with endothelial cells, the key cell type involved in the formation of blood vessels. Despite such proximity of VEGF-responsive cells, hematopoiesis occurs independently of neoangiogenesis in the adult bone marrow, suggesting that VEGF regulates the two processes by different mechanisms. In support of this hypothesis, the recently identified autocrine loop by which VEGF may control hematopoietic stem cell survival and repopulation, is fundamentally different from its paracrine effects regulating angiogenesis. Furthermore, coexpression of VEGF and its receptors, the prerequisite for autocrine loops, is frequently found in lymphomas and myelomas, suggesting that autocrine loops also play a role in hematological malignancies. Several therapeutic strategies blocking VEGF or VEGF-induced signaling are currently being investigated for the treatment of neoplastic diseases. They differ in their potential to interfere with the autocrine or paracrine effector functions of VEGF during angiogenesis, hematopoiesis, and tumor cell proliferation, properties which may ultimately determine their therapeutic potential.
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Affiliation(s)
- Hans-Peter Gerber
- Department of Molecular Oncology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
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292
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Zhang H, Wu J, Meng L, Shou CC. Expression of vascular endothelial growth factor and its receptors KDR and Flt-1 in gastric cancer cells. World J Gastroenterol 2002; 8:994-8. [PMID: 12439912 PMCID: PMC4656405 DOI: 10.3748/wjg.v8.i6.994] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: The expression of vascular endothelial growth factor (VEGF) and its receptors KDR and Flt-1 by gastric carcinoma tissues and different gastric carcinoma cell lines was detected to elucidate the molecular mechanism of this growth factor in promoting tumor growth.
METHODS: The expression of VEGF, Flt-1 and KDR was determined by reverse transcription-polymerase chain reaction (RT-PCR) in gastric cancer cell lines RF-1, RF-48, AGS-1, NCI-N87, NCI-SNU-1, NCI-SNU-5, NCI-SNU-16 and KATO-III. The expression of Flt-1 and KDR in paraffin-embedded specimens of gastric cancer was determined by immunohistochemistry. The 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was used to assess the role of VEGF in tumor cell proliferation.
RESULTS: All 8 gastric cancer cell lines analyzed expressed VEGF121 and VEGF165 and six of them expressed both Flt-1 and KDR, while cell line NCI-SNU-5 expressed Flt-1 only and cell line KATOIII expressed neither Flt-1 nor KDR. The gastric carcinoma tissues expressed Flt-1 and KDR widely, with the positive rate of expression of Flt-1 and KDR being 84.6% and 70% respectively. The exogenous VEGF stimulated the growth of KDR-positive cell lines NCI-N87 and AGS-1 in a dose-dependent manner but exhibited no effect on the growth of KDR-negative cell line NCI-N87.
CONCLUSION: VEGF and its receptors KDR and Flt-1 were expressed widely in gastric carcinoma cells and the VEGF stimulated KDR-positive tumor cell growth directly. These results suggest that VEGF may play a role in promoting tumor growth and metastasis by participating in both paracrine and autocrine pathways.
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Affiliation(s)
- Hua Zhang
- Department of Biochemistry and Molecular Biology, Peking University School of Oncology, Beijing Institute for Cancer Research, China
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293
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Schuch G, Machluf M, Bartsch G, Nomi M, Richard H, Atala A, Soker S. In vivo administration of vascular endothelial growth factor (VEGF) and its antagonist, soluble neuropilin-1, predicts a role of VEGF in the progression of acute myeloid leukemia in vivo. Blood 2002; 100:4622-8. [PMID: 12453880 DOI: 10.1182/blood.v100.13.4622] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Recent findings implied that the progression of hematologic malignancies, like that of solid tumors, is dependent on neovascularization. Recent studies on patients with acute myeloid leukemia (AML) showed increased levels of leukocyte-associated vascular endothelial growth factor (VEGF) and neovascularization of the bone marrow. Murine (32D, M1) and human (HEL, U937, and UKE-1) leukemic cell lines and freshly isolated leukemic cells were analyzed for the expression of VEGF and VEGF receptor mRNA. The expression of VEGF and VEGF receptors KDR and neuropilin-1 (NRP-1) was detected in these cells. In a murine chloroma model, delivery of VEGF(165) using microencapsulation technology resulted in enhanced tumor growth and vascularization, whereas treatment with a VEGF antagonist soluble NRP-1 (sNRP-1) inhibited tumor angiogenesis and growth. In a systemic leukemia model, survival of mice injected with adenovirus (Ad) encoding for Fc-sNRP-1 (sNRP-1 dimer) was significantly prolonged as compared with mice injected with Ad-LacZ. Further analyses showed a reduction in circulating leukemic cells and infiltration of liver and spleen as well as bone marrow neovascularization and cellularity. Taken together, these results demonstrate that angiogenic factors such as VEGF promote AML progression in vivo. The use of VEGF antagonists as an antiangiogenesis approach offers a potential treatment for AML. Finally, our novel in vivo drug delivery model may be useful for testing the activities of other peptide antiangiogenic factors.
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MESH Headings
- Acute Disease
- Animals
- Disease Progression
- Endothelial Growth Factors/antagonists & inhibitors
- Endothelial Growth Factors/biosynthesis
- Endothelial Growth Factors/genetics
- Endothelial Growth Factors/pharmacology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Gene Expression Regulation, Leukemic
- Genetic Therapy
- Humans
- Intercellular Signaling Peptides and Proteins/biosynthesis
- Intercellular Signaling Peptides and Proteins/genetics
- Intercellular Signaling Peptides and Proteins/pharmacology
- Leukemia, Experimental/genetics
- Leukemia, Experimental/metabolism
- Leukemia, Experimental/pathology
- Leukemia, Experimental/therapy
- Leukemia, Myeloid/metabolism
- Leukemia, Myeloid/pathology
- Lymphokines/antagonists & inhibitors
- Lymphokines/biosynthesis
- Lymphokines/genetics
- Lymphokines/pharmacology
- Mice
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- Neoplasm Proteins/physiology
- Neovascularization, Pathologic/physiopathology
- Neuropilin-1/genetics
- Neuropilin-1/physiology
- Phosphorylation
- Protein Processing, Post-Translational
- RNA, Messenger/biosynthesis
- RNA, Neoplasm/biosynthesis
- Recombinant Fusion Proteins/physiology
- Reverse Transcriptase Polymerase Chain Reaction
- Solubility
- Swine
- Transfection
- Tumor Cells, Cultured/chemistry
- Tumor Cells, Cultured/drug effects
- Tumor Cells, Cultured/metabolism
- U937 Cells/metabolism
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factor Receptor-2/biosynthesis
- Vascular Endothelial Growth Factor Receptor-2/genetics
- Vascular Endothelial Growth Factors
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Affiliation(s)
- Gunter Schuch
- Department of Urology, Laboratory for Cellular Therapeutics, Children's Hospital, Boston, MA 02115, USA
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294
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Niethammer AG, Xiang R, Becker JC, Wodrich H, Pertl U, Karsten G, Eliceiri BP, Reisfeld RA. A DNA vaccine against VEGF receptor 2 prevents effective angiogenesis and inhibits tumor growth. Nat Med 2002; 8:1369-75. [PMID: 12415261 DOI: 10.1038/nm1202-794] [Citation(s) in RCA: 249] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2002] [Accepted: 10/08/2002] [Indexed: 11/09/2022]
Abstract
Tumor cells are elusive targets for immunotherapy due to their heterogeneity and genetic instability. Here we describe a novel, oral DNA vaccine that targets stable, proliferating endothelial cells in the tumor vasculature rather than tumor cells. Targeting occurs through upregulated vascular-endothelial growth factor receptor 2 (FLK-1) of proliferating endothelial cells in the tumor vasculature. This vaccine effectively protected mice from lethal challenges with melanoma, colon carcinoma and lung carcinoma cells and reduced growth of established metastases in a therapeutic setting. CTL-mediated killing of endothelial cells indicated breaking of peripheral immune tolerance against this self antigen, resulting in markedly reduced dissemination of spontaneous and experimental pulmonary metastases. Angiogenesis in the tumor vasculature was suppressed without impairment of fertility, neuromuscular performance or hematopoiesis, albeit with a slight delay in wound healing. Our strategy circumvents problems in targeting of genetically unstable tumor cells. This approach may provide a new strategy for the rational design of cancer therapies.
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295
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Ho CL, Sheu LF, Li CY. Immunohistochemical expression of basic fibroblast growth factor, vascular endothelial growth factor, and their receptors in stage IV non-Hodgkin lymphoma. Appl Immunohistochem Mol Morphol 2002; 10:316-21. [PMID: 12607599 DOI: 10.1097/00129039-200212000-00005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Angiogenesis is increased in hematologic malignancies, including non-Hodgkin lymphoma (NHL). Elevated serum levels of two important angiogenic factors, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), are associated with a poor prognosis. Immunohistochemistry was used to evaluate 27 patients with NHL and bone marrow involvement (17 with low-grade B-cell NHL, including 7 with higher grade transformation; 6 with intermediate-grade B-cell NHL; and 4 with T-cell lymphoma). Among the 17 patients with low-grade B-cell NHL, results for 7 were positive for VEGF stain (41.2%), and results were negative for all other stains for VEGF receptors, bFGF, and bFGF receptors. In the 10 patients with intermediate-grade B-cell NHL and T-cell lymphoma, all VEGF staining was positive (100%), but bFGF staining was only weakly positive in 2. Staining results for seven patients who had low-grade B-cell NHL with higher grade transformation showed that VEGF staining was positive in large lymphoid cells of 5 patients and in small lymphoid cells of one patient. Staining for the receptors VEGFR-1 and VEGFR-2 was positive in large lymphoid cells in four and two cases, respectively. Staining for bFGF was positive in two cases of large lymphoid cells. We concluded that VEGF, but not bFGF, was associated with higher tumor grading of NHL and high-grade transformation of low-grade lymphoma.
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Affiliation(s)
- Ching-Liang Ho
- Division of Hematopathology, Mayo Clinic, Rochester, Minnesota 55905, USA
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296
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Zhang L, Yang N, Garcia JRC, Mohamed A, Benencia F, Rubin SC, Allman D, Coukos G. Generation of a syngeneic mouse model to study the effects of vascular endothelial growth factor in ovarian carcinoma. THE AMERICAN JOURNAL OF PATHOLOGY 2002; 161:2295-309. [PMID: 12466143 PMCID: PMC1850900 DOI: 10.1016/s0002-9440(10)64505-1] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Vascular endothelial growth factor (VEGF) performs multifaceted functions in the tumor microenvironment promoting angiogenesis, suppressing anti-tumor immune response, and possibly exerting autocrine functions on tumor cells. However, appropriate syngeneic animal models for in vivo studies are lacking. Using retroviral transfection and fluorescence-activated cell sorting, we generated a C57BL6 murine ovarian carcinoma cell line that stably overexpresses the murine VEGF164 isoform and the enhanced green fluorescent protein. VEGF164 overexpression dramatically accelerated tumor growth and ascites formation, significantly enhanced tumor angiogenesis, and substantially promoted the survival of tumor cells in vivo. In vitro, VEGF164 overexpression significantly enhanced cell survival after growth factor withdrawal and conferred resistance to apoptosis induced by cis-platin through an autocrine mechanism. VEGF/green fluorescent protein-expressing tumors were not recognized by the adaptive immune system. After vaccination, a specific anti-tumor T-cell response was detected, but tumor growth was not inhibited. This engineered murine carcinoma model should prove useful in the investigation of the role of VEGF in modulating the tumor microenvironment and affecting the complex interactions among angiogenesis mechanisms, anti-tumor immune mechanisms, and tumor cell behavior at the natural state or during therapy in ovarian carcinoma.
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Affiliation(s)
- Lin Zhang
- Center for Research on Reproduction and Women's Health, University of Pennsylvania, 421 Curie Boulevard, Philadelphia, PA 19104, USA
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297
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Rafii S, Lyden D, Benezra R, Hattori K, Heissig B. Vascular and haematopoietic stem cells: novel targets for anti-angiogenesis therapy? Nat Rev Cancer 2002; 2:826-35. [PMID: 12415253 DOI: 10.1038/nrc925] [Citation(s) in RCA: 486] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Shahin Rafii
- Division of Hematology-Oncology, Cornell University Medical College, 1300 York Avenue, Room D601, New York, New York 10021, USA.
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298
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de Bont ESJM, Neefjes VME, Rosati S, Vellenga E, Kamps WA. New vessel formation and aberrant VEGF/VEGFR signaling in acute leukemia: does it matter? Leuk Lymphoma 2002; 43:1901-9. [PMID: 12481883 DOI: 10.1080/1042819021000015844] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Although many patients with acute leukemia achieve a hematological complete remission with aggressive intensive therapy protocols, a large proportion shows reoccurrence of disease. Novel strategies are warranted. In acute leukemia new vessel formation is observed. New vessel formation is the result of angiogenesis and vasculogenesis. The degree of neovascularization in the bone marrow is correlated with vascular endothelial growth factor (VEGF) expression in the leukemic cells. The present review discusses the impact of new vessel formation related to acute leukemia, the relation with various angiogenic factors and will focus on VEGF/VEGF receptor signaling.
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Affiliation(s)
- E S J M de Bont
- Division of Pediatric Oncology, Department of Pediatrics, Beatrix Children's Hospital, University Hospital Groningen, PO Box 30.001, 9700 RB Groningen, The Netherlands.
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299
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Sepp-Lorenzino L, Thomas KA. Antiangiogenic agents targeting vascular endothelial growth factor and its receptors in clinical development. Expert Opin Investig Drugs 2002; 11:1447-65. [PMID: 12387705 DOI: 10.1517/13543784.11.10.1447] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
There is ample therapeutic opportunity for the use of antiangiogenic inhibitors in the clinic, as there are several human diseases that are dependent upon angiogenesis [1]. However, no disease has attracted as much attention as a target for antiangiogenic therapy as malignant disorders. There is a vast amount of literature acting as proof-of-principle for the use of angiogenic inhibitors as effective agents for blocking tumour-induced angiogenesis and subverting tumour growth and disease dissemination. One of the unique attractions of targeting tumour angiogenesis is that vascular endothelial cells are a genetically stable population in which acquisition of therapeutic resistance might be less efficient than in genetically unstable tumour cells [2,3]. This review covers inhibitors that target the tumour angiogenic agent vascular endothelial growth factor and its receptors as one such antiangiogenic approach. Many agents in this class are in clinical trials with limited reports of toxicity and some early evidence of clinical benefit.
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Affiliation(s)
- Laura Sepp-Lorenzino
- Department of Cancer Research, Merck Research Laboratories, WP26-462, West Point, PA 19486, USA.
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300
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Abstract
Antiangiogenic drugs are unique for having highly specific targets while carrying the potential to be effective against a wide variety of tumors. Moreover, some of the major limitations of cytotoxic therapies likely will be avoided by this entirely new class of anticancer weapons. After the realization of the potential advantages of antiangiogenic therapy, the field of angiogenesis research is growing exponentially. Still, there is much to learn about the machinery that tumors use to recruit new blood vessels, and the results of the clinical trials will show the best way to apply that knowledge for cancer therapy.
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MESH Headings
- Angiogenesis Inhibitors/pharmacology
- Angiogenesis Inhibitors/therapeutic use
- Angiostatins
- Animals
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal/therapeutic use
- Anticarcinogenic Agents/pharmacology
- Anticarcinogenic Agents/therapeutic use
- Cell Hypoxia/physiology
- Child
- Clinical Trials as Topic
- Collagen/physiology
- Cyclooxygenase Inhibitors/pharmacology
- Cyclooxygenase Inhibitors/therapeutic use
- Drug Design
- Endostatins
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/pathology
- Ephrins/physiology
- Growth Substances/physiology
- Humans
- Immunotherapy
- Integrin alphaVbeta3/antagonists & inhibitors
- Integrin alphaVbeta3/physiology
- Ligases/physiology
- Matrix Metalloproteinase Inhibitors
- Matrix Metalloproteinases/physiology
- Mice
- Neoplasm Proteins/antagonists & inhibitors
- Neoplasm Proteins/physiology
- Neoplasms/blood supply
- Neoplasms/drug therapy
- Neovascularization, Pathologic/drug therapy
- Outcome Assessment, Health Care
- Peptide Fragments/physiology
- Plasminogen/physiology
- Protease Inhibitors/pharmacology
- Protease Inhibitors/therapeutic use
- Receptors, Eph Family/antagonists & inhibitors
- Receptors, Eph Family/physiology
- Receptors, Growth Factor/antagonists & inhibitors
- Receptors, Growth Factor/physiology
- Thrombospondins/physiology
- Tumor Suppressor Proteins
- Ubiquitin-Protein Ligases
- Von Hippel-Lindau Tumor Suppressor Protein
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Affiliation(s)
- Kerim Kaban
- Department of Thoracic Head and Neck Medical Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
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