Acidic and Basic Fibroblast Growth Factors Are Present in ... · some 2 (5). Endothelial cell...
7
JCANCER RESEARCH 51, 5760-5765, October 15, 1991] Acidic and Basic Fibroblast Growth Factors Are Present in Glioblastoma Multiforme1 David F. Stefanik,2 Laila R. Rizkalla, Anuradha Soi, Sidney A. Goldblatt, and Waheeb M. Rizkalla Department of Radiation Oncology, Laurel Highlands Cancer Program [D. F. S.], and the Department of Pathology, Conemaugh Valley Memorial Hospital [L. R. R., A. S., S. A. G., W. M. R.J, Johnstown, Pennsylvania 15905 ABSTRACT Immunohistochemistry was performed on paraffin sections from hu man glioblastoma multiforme and normal brain tissue. Acidic fibroblast growth factor (FGF) was abundantly present in astrocytes from all glioblastomas studied. Basic FGF was found in the matrix surrounding proliferating blood vessels in most of the glioblastomas. In contrast, astrocytes from normal brain did not contain acidic FGF, and peri vascular matrix staining was not demonstrated for basic FGF in the normal brain. Both growth factors could be demonstrated in neurons, Purkinje cells, capillary endothelium, and arterial walls in the normal brain. This study implicates both growth factors in the pathogenesis of malignant glioma. Both may be significant mediators of angiogenesis in glioblastoma. INTRODUCTION Glioblastoma multiforme is a uniformly fatal brain tumor. Approximately 10,000 cases occur yearly in the United States (1). The tumor arises from the astrocytic series of neuroglial cells. It contains both poorly differentiated and pleomorphic cellular elements; hence, the name glioblastoma multiforme. Microscopically, these tumors are characterized by bizarre ap pearing cells with hyperchromatic nuclei, giant cells, and fre quent mitotic figures. Various descriptive terms have been given to the pleomorphic cells. Plump distended astrocytes are gem- istocytes; elongated fibril-producing cells are fibrillary astro cytes; thin hair-like cells are pilocytic astrocytes. Protoplasmic astrocytes are normal constituents of gray matter. They have short processes which terminate on blood vessels. Most glio blastomas are pleomorphic. They are mixtures of the various cell types. Abundant neovascularization is a hallmark of these tumors. Necrotic segments are common. Tumors of astrocytic origin are assigned grades I-IV with grade IV being the most anaplastic and clinically aggressive (2). Grade III and IV gliomas are classified as "malignant" because of their rapid progressive course. In this study we evaluated 12 high grade (III and IV) gliomas using the general descriptive term, glio blastoma multiforme. Acidic and basic FGFs3 are members of the class of angi- ogenic factors with affinity for heparin. Both are capable of stimulating proliferation and motility of endothelial cells. They are the prototype molecules within each class of heparin affinic growth factors and are believed to play an essential role in angiogenesis (3). They are distinct but structurally related mol ecules sharing sequence homology through 53% of their pri mary structure (4). The genes for acidic FGF are found on Received 2/25/91; accepted 8/2/91. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. 1This work was supported by the Conemaugh Valley Memorial and Lee Hospitals, both of which are members of the Laurel Highlands Cancer Program. The Laurel Highlands Cancer Program is a member of the Pittsburgh Cancer Institute's Community Network. 'To whom requests for reprints should be addressed, at Department of Radiation Oncology, Laurel Highlands Cancer Program, 1086 Franklin Street, Johnstown, PA 15905. 1The abbreviations used are: FGF, fibroblast growth factor; PBS, phosphate- buffered saline. chromosome 5, while those for basic FGF reside on chromo some 2 (5). Endothelial cell growth factor is the precursor of acidic FGF (6). Both acidic and basic fibroblast growth factors have been isolated from neural tissues (7). MATERIALS AND METHODS To determine whether the fibroblast growth factors are present in glioblastoma multiforme, we performed immunohistochemistry on par affin-embedded tissue. Neutralizing polyclonal antibodies to acidic and basic fibroblast growth factors were used (F.G.F. Co., La .lolla, CA). The antibodies were prepared in rabbits against bovine antigen and purified by the manufacturer using protein A Sepharose chromatogra- phy. As a control, slides were probed with purified polyclonal rabbit immunoglobulin from nonimmunized animals (Dako Corp., Carpin terÃ-a, CA). To demonstrate the specificity of each antibody, additional slides were processed after the antibody was absorbed with antigen. Twelve tumors were probed. Brain tissues from five victims of trauma served as a normal tissue control. The Vectastain avidin-biotin complex peroxidase kit was used for detection (Vector Labs, Inc., Burlingame, CA). Ten ^g of each polyclonal antibody was applied per slide. Five- ¿tm slides were prepared on a microtome. They were deparaffinized in xylene, dehydrated in ethanol, rinsed for 5 min in PBS, incubated for 30 min in 0.3% H2O2 in methanol, washed in PBS for 10 min, preincubated in 1.5% goat serum for 30 min, incubated for 30 min with the primary antibody in PBS, 1.5% bovine serum albumin, washed for 10 min in PBS, incubated for 30 min with biotinylated sheep antibodies to rabbit IgG, washed for 10 min in PBS, incubated for 30 min with avidin-biotin complex, washed for 10 min in PBS, incubated for 4 min with the chromagen, diaminobenzidine, washed for 5 min in tap water, and counterstained with Mayer's hematoxylin. For those slides preab- sorbed with antigen, the primary antibody was prepared by adding 5 ¿ig of antigen to 10 Mgof antibody in 50 *ilof PBS, pH 7.2. The solution was shaken gently for 4 h, incubated overnight at room temperature, and centrifuged at 7000 rpm for 10 min in a microfuge. The supernatant was utilized as the primary antibody. RESULTS The distribution of acidic and basic fibroblast growth factors in normal brain tissue is demonstrated in Fig. 1. Acidic fibro blast growth factor was detected in capillary endothelial cells and within the walls of leptomeningeal arteries where it could be seen strikingly in the adventitial, as well as the muscular, layer. It was also detected in the cerebellar Purkinje cells and cortical neurons. Astrocytes failed to stain for acidic FGF. Basic FGF was found in fewer subpopulations of cells than acidic FGF in the normal brain. Like acidic FGF, basic FGF could be seen in the muscular layer of large blood vessels. However, the adventitia was spared. Purkinje cells also demonstrated staining for basic FGF. Sporadic neurons and capillaries demonstrated staining which was less dramatic in comparison to acidic FGF. These findings are summarized in Table 1. Twelve high grade gliomas were evaluated (Fig. 2). The pattern of staining was consistent. All 12 contained numerous astrocytes whose cytoplasm stained for acidic FGF. The inten sity of the stain was considerably greater in the malignant as 5760 on June 8, 2020. © 1991 American Association for Cancer Research. cancerres.aacrjournals.org Downloaded from
Transcript of Acidic and Basic Fibroblast Growth Factors Are Present in ... · some 2 (5). Endothelial cell...
JCANCER RESEARCH 51, 5760-5765, October 15, 1991]
Acidic and Basic Fibroblast Growth Factors Are Present in GlioblastomaMultiforme1
David F. Stefanik,2 Laila R. Rizkalla, Anuradha Soi, Sidney A. Goldblatt, and Waheeb M. Rizkalla
Department of Radiation Oncology, Laurel Highlands Cancer Program [D. F. S.], and the Department of Pathology, Conemaugh Valley Memorial Hospital [L. R. R.,A. S., S. A. G., W. M. R.J, Johnstown, Pennsylvania 15905
ABSTRACT
Immunohistochemistry was performed on paraffin sections from human glioblastoma multiforme and normal brain tissue. Acidic fibroblastgrowth factor (FGF) was abundantly present in astrocytes from allglioblastomas studied. Basic FGF was found in the matrix surroundingproliferating blood vessels in most of the glioblastomas. In contrast,astrocytes from normal brain did not contain acidic FGF, and peri vascularmatrix staining was not demonstrated for basic FGF in the normal brain.Both growth factors could be demonstrated in neurons, Purkinje cells,capillary endothelium, and arterial walls in the normal brain. This studyimplicates both growth factors in the pathogenesis of malignant glioma.Both may be significant mediators of angiogenesis in glioblastoma.
INTRODUCTION
Glioblastoma multiforme is a uniformly fatal brain tumor.Approximately 10,000 cases occur yearly in the United States(1). The tumor arises from the astrocytic series of neuroglialcells. It contains both poorly differentiated and pleomorphiccellular elements; hence, the name glioblastoma multiforme.Microscopically, these tumors are characterized by bizarre appearing cells with hyperchromatic nuclei, giant cells, and frequent mitotic figures. Various descriptive terms have been givento the pleomorphic cells. Plump distended astrocytes are gem-istocytes; elongated fibril-producing cells are fibrillary astrocytes; thin hair-like cells are pilocytic astrocytes. Protoplasmicastrocytes are normal constituents of gray matter. They haveshort processes which terminate on blood vessels. Most glioblastomas are pleomorphic. They are mixtures of the variouscell types. Abundant neovascularization is a hallmark of thesetumors. Necrotic segments are common. Tumors of astrocyticorigin are assigned grades I-IV with grade IV being the mostanaplastic and clinically aggressive (2). Grade III and IVgliomas are classified as "malignant" because of their rapid
progressive course. In this study we evaluated 12 high grade(III and IV) gliomas using the general descriptive term, glioblastoma multiforme.
Acidic and basic FGFs3 are members of the class of angi-
ogenic factors with affinity for heparin. Both are capable ofstimulating proliferation and motility of endothelial cells. Theyare the prototype molecules within each class of heparin affinicgrowth factors and are believed to play an essential role inangiogenesis (3). They are distinct but structurally related molecules sharing sequence homology through 53% of their primary structure (4). The genes for acidic FGF are found on
Received 2/25/91; accepted 8/2/91.The costs of publication of this article were defrayed in part by the payment
of page charges. This article must therefore be hereby marked advertisement inaccordance with 18 U.S.C. Section 1734 solely to indicate this fact.
1This work was supported by the Conemaugh Valley Memorial and LeeHospitals, both of which are members of the Laurel Highlands Cancer Program.The Laurel Highlands Cancer Program is a member of the Pittsburgh CancerInstitute's Community Network.
'To whom requests for reprints should be addressed, at Department ofRadiation Oncology, Laurel Highlands Cancer Program, 1086 Franklin Street,Johnstown, PA 15905.
1The abbreviations used are: FGF, fibroblast growth factor; PBS, phosphate-
buffered saline.
chromosome 5, while those for basic FGF reside on chromosome 2 (5). Endothelial cell growth factor is the precursor ofacidic FGF (6). Both acidic and basic fibroblast growth factorshave been isolated from neural tissues (7).
MATERIALS AND METHODS
To determine whether the fibroblast growth factors are present inglioblastoma multiforme, we performed immunohistochemistry on paraffin-embedded tissue. Neutralizing polyclonal antibodies to acidic andbasic fibroblast growth factors were used (F.G.F. Co., La .lolla, CA).The antibodies were prepared in rabbits against bovine antigen andpurified by the manufacturer using protein A Sepharose chromatogra-phy. As a control, slides were probed with purified polyclonal rabbitimmunoglobulin from nonimmunized animals (Dako Corp., CarpinterÃa,CA). To demonstrate the specificity of each antibody, additionalslides were processed after the antibody was absorbed with antigen.Twelve tumors were probed. Brain tissues from five victims of traumaserved as a normal tissue control. The Vectastain avidin-biotin complexperoxidase kit was used for detection (Vector Labs, Inc., Burlingame,CA). Ten ^g of each polyclonal antibody was applied per slide. Five-¿tmslides were prepared on a microtome. They were deparaffinized inxylene, dehydrated in ethanol, rinsed for 5 min in PBS, incubated for30 min in 0.3% H2O2 in methanol, washed in PBS for 10 min,preincubated in 1.5% goat serum for 30 min, incubated for 30 min withthe primary antibody in PBS, 1.5% bovine serum albumin, washed for10 min in PBS, incubated for 30 min with biotinylated sheep antibodiesto rabbit IgG, washed for 10 min in PBS, incubated for 30 min withavidin-biotin complex, washed for 10 min in PBS, incubated for 4 minwith the chromagen, diaminobenzidine, washed for 5 min in tap water,and counterstained with Mayer's hematoxylin. For those slides preab-
sorbed with antigen, the primary antibody was prepared by adding 5 ¿igof antigen to 10 Mgof antibody in 50 *ilof PBS, pH 7.2. The solutionwas shaken gently for 4 h, incubated overnight at room temperature,and centrifuged at 7000 rpm for 10 min in a microfuge. The supernatantwas utilized as the primary antibody.
RESULTS
The distribution of acidic and basic fibroblast growth factorsin normal brain tissue is demonstrated in Fig. 1. Acidic fibroblast growth factor was detected in capillary endothelial cellsand within the walls of leptomeningeal arteries where it couldbe seen strikingly in the adventitial, as well as the muscular,layer. It was also detected in the cerebellar Purkinje cells andcortical neurons. Astrocytes failed to stain for acidic FGF. BasicFGF was found in fewer subpopulations of cells than acidicFGF in the normal brain. Like acidic FGF, basic FGF could beseen in the muscular layer of large blood vessels. However, theadventitia was spared. Purkinje cells also demonstrated stainingfor basic FGF. Sporadic neurons and capillaries demonstratedstaining which was less dramatic in comparison to acidic FGF.These findings are summarized in Table 1.
Twelve high grade gliomas were evaluated (Fig. 2). Thepattern of staining was consistent. All 12 contained numerousastrocytes whose cytoplasm stained for acidic FGF. The intensity of the stain was considerably greater in the malignant as
5760
on June 8, 2020. © 1991 American Association for Cancer Research. cancerres.aacrjournals.org Downloaded from
ACIDIC AND BASIC FGF IN GLIOBLASTOMA
k.**
Fig. 1.on June 8, 2020. © 1991 American Association for Cancer Research. cancerres.aacrjournals.org Downloaded from
ACIDIC AND BASIC FGF IN GLIOBLASTOMA
Fig. 2.
on June 8, 2020. © 1991 American Association for Cancer Research. cancerres.aacrjournals.org Downloaded from
ACIDIC AND BASIC FGF IN GLIOBLASTOMA
Table 1 Summary of findings
FGF Glioblastoma Normal brain
Acidic Abundantly present ingemistocytic astro-cytes throughout tumor
Basic Present in perivascularmatrix
Not present in astrocytes
Present in Purkinje cells,capillary endothelium,neurons, and muscularand adventitial layers oflarge arteries
Not present in perivascularmatrix
Present in Purkinje cells,muscular layer of largearteries, and faintly insporadic neurons andcapillaries
•¿�
Fig. 3. Basic FGF is demonstrated within the walls of a thick walled proliferating blood vessel in glioblastoma multiforme (x 400).
opposed to normal tissue. The cytoplasm of gemistocytic andprotoplasmic astrocytes stained most intensely. In nine of the12 tumors, staining was uniform throughout the tumor. Thevast majority of malignant astrocytes contained acidic FGF.However, in three tumors the staining was heterogenous withareas of solid unstained cells. Tumors contain multiple subpop-ulations of cells. Heterogenous staining has been reported inthe immunohistochemical analysis of other tumors (8). Thesefindings concur with a report that glioma cells in culture produce acidic FGF (9).
Basic FGF was demonstrated in nine of the 12 tumors studied(Fig. 2). Staining was intense in the matrix surrounding proliferating blood vessels. In some sections basic FGF could be seenwithin the walls of the tumor vasculature (Fig. 3). Fibrillaryastrocytes stained for basic FGF. The distribution of basic FGFwas inhomogenous throughout the tumors. Typically, segments
of gemistocytic or protoplasmic astrocytes were unstained,while focal stretches of interstitial matrix stained positively.The inhomogeneity of distribution may account for the lack ofstaining in three of the tumors.
The specificity of each antibody for the antigen in questionis demonstrated in Fig. 4. Absorption with antigen resulted ininhibition of cytoplasmic staining for anti-acidic FGF andperivascular matrix staining for anti-basic FGF.
DISCUSSION
This study adds to a growing list of reports which implicatethe fibroblast growth factors in the pathogenesis of humanglioma. The presence of RNA coding acidic and basic FGFswas demonstrated by Takahashi et al. (10) using Northern blotanalysis. In their study, 17 of 18 gliomas expressed basic FGF,while 13 of 18 expressed acidic FGF. One tumor was probedfor basic FGF using in situ hybridization and immunohisto-chemistry. Hybridization signal was detected in malignant cellsas well as within endothelial cells of blood vessels. Immunohis-tochemistry confirmed the presence of the basic FGF proteinin malignant cells. Other studies have demonstrated the presence of acidic FGF, basic FGF, and receptors for basic FGF incultured human glioma cells (11-13).
Staining for acidic FGF was exclusively intracellular. BasicFGF was demonstrated in the cytoplasm of fibrillary astrocytes.It also appeared to be present in the matrix surrounding proliferating vessels. Conclusions cannot be reached from this studyregarding the mechanics of extracellular deposition. The fibroblast growth factors lack classic secretory signal sequences (4).Folkman and Klagsbrun (3) have speculated that release fromcells might occur after cellular damage or under tightly regulated conditions.
Basic FGF has been demonstrated in bovine corneal basement membrane and in developing retinal capillaries (14, 15).It has been demonstrated in the subendothelial extracellularmatrix of cultured bovine corneal and endothelial cells (16).Folkman et al. postulated that these structures may serve asstorage depots which regulate the accessibility of the moleculeto the vascular endothelium. They hypothesized that tissueinjury could release basic FGF, thereby triggering angiogenesis.In this study we demonstrated the presence of both acidic andbasic FGF in the cytoplasm of neurons, endothelium, andPurkinje cells. They may also serve as reservoirs for the vascularmitogens.
There was a considerable difference in the staining of malignant as opposed to normal brain tissue for both acidic and basicFGF. This is summarized in Table 1. In normal brain tissueacidic FGF was not demonstrated in astrocytes. In contrast,glioblastoma contains a large population of intensely staining
Fig. 1. Immunohistochemistry of normal brain tissue of a trauma victim. Affinity-purified rabbit polyclonal antibodies to acidic FGF (A-C) and basic FGF (D-F)were used as the primary antibodies. The purified IgG fraction of rabbit serum from nonimmunized animals (G-l) was used as a control. A, acidic FGF is demonstratedin capillary endothelial cells and cortical neurons. Astrocytes failed to stain (x 400). //. acidic FGF is demonstrated in cerebellar Purkinje cells and in the cytoplasmof adjacent neurons (X 400). C, acidic FGF is demonstrated in the muscular layer and adventitia of a leptomeningeal artery (x 400). D, cortical neurons, capillaryendothelial cells, and astrocytes fail to stain for basic FGF (x 400). E, basic FGF is demonstrated in the cytoplasm of a cerebellar Purkinje cell. Weak staining is alsoseen in a nearby capillary and neurons (x 400). F, the muscular layer of a leptomeningeal artery stains for basic FGF. The adventitial layer is relatively spared of thestain (x 200). G-l, purified nonimmune rabbit serum demonstrates no staining (G and //, x 400; /, x 200).
Fig. 2. Distribution of acidic and basic fibroblast growth factors in glioblastoma multiforme. The primary antibody is anti-acidic FGF (A, D, and G), anti-basicFGF (B, E, and //), and nonimmune polyclonal rabbit immunoglobulin (C, F, and /). A-C, glioblastoma 1: acidic FGF is demonstrated in the cytoplasm of astrocytesclustered about a blood vessel. Basic FGF is seen outlining the lumina of numerous blood vessels. It can be seen within some of the vascular walls. The controlantibody demonstrates no staining (A, x 100; B and C, x 200). D-F, glioblastoma 2: astrocytes stain deeply for acidic FGF. Basic FGF is demonstrated along fibrillaryastrocytes and the perivascular matrix. The gemistocytic astrocytes which stain for acidic FGF are unstained for basic FGF. Control polyclonal antibodies show nostaining (D, x 200; E and F, x 100). G-I, glioblastoma 3: heterogenous staining for acidic FGF is demonstrated. Basic FGF is demonstrated intensely in the matrixsurrounding numerous proliferating blood vessels. The control slide demonstrates no staining ((¡I, x 200).
5763
on June 8, 2020. © 1991 American Association for Cancer Research. cancerres.aacrjournals.org Downloaded from
ACIDIC AND BASIC FGF IN GLIOBLASTOMA
Fig. 4. Immune staining is inhibited by absorption of the antibody with antigen..-( and B, a glioblastoma is immunohistochemically probed with anti-acidic FGF(A) and anti-basic FGF (B). Note presence of staining for both antibodies. C and D, adjacent sections from the same tumor are probed with anti-acidic FGF absorbedwith acidic FGF (Q and anti-basic FGF absorbed with basic FGF (D). Inhibition of staining in comparison with .I and B demonstrates that both antibodies recognizetheir respective antigens.
gemistocytic astrocytes. Often they were clustered about bloodvessels. In gliobliostoma basic FGF was abundantly present inthe matrix surrounding proliferating blood vessels. This wasnot seen in the perivascular matrix from any section of normalbrain examined.
Neovascularization is a necessary phenomenon for both normal and neoplastic growth. Tumor growth is dependent uponthe ability of the tumor to recruit a vasculature. Glioblastomamultiforme is a lethal brain tumor characterized by aberrantneovascularization. Thick walled proliferative vascular channelsare common. Both acidic and basic fibroblast growth factorsare mitogenic for endothelial, as well as glial, cells. Both areexpressed abundantly in glioblastoma. Each has a unique pattern of distribution. The gemistocytic and protoplasmic astrocytes which stained for acidic FGF failed to stain for basicFGF. Fibrillary astrocytes produced basic but not acidic FGF.This indicates that each growth factor is produced by a separatesubpopulation of cells. Acidic FGF was seen in the cytoplasmof astrocytes, often in proximity to blood vessels (Fig. 2). BasicFGF was consistently demonstrated in the matrix around proliferating blood vessels (Fig. 2). It could also be seen withinsome vessel walls (Fig. 3). Close proximity to the vasculaturesuggests a role for both fibroblast growth factors in the angi-ogenic process. The abundant presence of both growth factorssuggests that each has a role in the pathogenesis of glioblastomamultiforme. In particular, the presence of basic FGF in peri-
vascular matrix and within tumor vasculature suggests that thismolecule plays a role in the vascular proliferation which accompanies glioblastoma multiforme.
ACKNOWLEDGMENTS
The authors thank Brad Goldblatt for technical assistance, Drs. PaulMonteleone and John Verger for critical review, and Cindy Miller,Karen Ryan, and Diane McLachlan for assistance in preparing themanuscript.
REFERENCES
1. Kornblith, P. L., Walker, M. D., and Cassady, J. R. Neoplasma of the centralnervous system. In: V. T. Devita, S. Hellman, and S. A. Rosenberg (eds.),Principles and Practices of Oncology, Vol. 2, Ed. 2, pp. 1437-1510. Philadelphia, PA: J. B. Lippincott Co., 1985.
2. Robbins, S. L. Pathological Basis of Disease. Philadelphia: W. B. SaundersCo., 1979.
3. Folkman, J., and Klagsbrun, M. Angiogenic factors. Science (WashingtonDC), 235:442-447, 1987.
4. Jaye, M., Howk, R., Burgess, W., et al. Human endothelial cell growth factor:cloning nucleotide sequence and chromosome localization. Science (Washington DC), 233: 541-544, 1986.
5. Mergia, A., Eddy, R., Abraham, J. A., Fiddes, J. C., and Shows, T. B. Thegenes for basic and acidic fibroblast growth factor are on different humanchromosomes. Biochem. Biophys. Res. Commun., 138: 644, 1986.
6. Gospodarowicz, D., Bialecki, H., and Greenburg, G. Purification of thefibroblast growth factor activity from bovine brain. J. Biol. ('hem., 253:3736-3743, 1978.
7. Maciag, T., Cenmdulo, I. S., Kelley, P. R., and Foranti. R. An endothelial
5764
on June 8, 2020. © 1991 American Association for Cancer Research. cancerres.aacrjournals.org Downloaded from
ACIDIC AND BASIC FGF IN GLIOBLASTOMA
cell growth factor from bovine hypothalamus: identification and partial 13. Megyesi, J. F., Klagsbrun. M., Folkman, J., Rosenthal. R. A., and Brigstock,characterization. Proc. Nati. Acad. Sci. USA, 76: 5674-5678. 1979. D. R. Analysis of fibroblast growth factors produced by a human glioblastoma
8. Viola, M. V., Fromowitz, F., Oravez, S., el al. Expression of ras oncogene, cell line: evidence from multiple b FGF proteins (Abstract). J. Cell Biochem.,p 21 in prostate cancer. N. Engl. J. Med., 314: I32-133, 1986. 224 (Suppl. F): CF119, 1991.
9. Marx, J. L. Oncogene action probed. Science (Washington DC), 237: 602- 14. Folkman, J., Klagsbrun, M., Sasse, J., Wadzinski, M., Ingber, D., and603, 1987. Vladavsky, I. A heparin binding angiogcnic protein—basic fibroblast growth
10. Takahashi, J. A., Mori, H., Fukumoto, M., et al. Gene expression of fibro- factor—is stored within basement membrane. Am J. Pathol., 130: 393-400,blast growth factors in human gliomas and meningiomas: demonstration of 1988.cellular source of basic fibroblast growth factor mRNA and peptide in tumor 15. Hanneken, A., Lutty, G. A., McLeod, D. S., Robey, F., Harvey, A. K., andtissues. Proc. Nati. Acad. Sci. USA, 87: 5710-5714, 1990. Hjelmeland. L. M. Localization of basic fibroblast growth factor to the
11. Morrison, R. S., Gross, J. L., Herblin. W. F., et al. Basic fibroblast growth developing capillaries of the bovine retina. J. Cell Physiol., 138: 115-120,factor-like activity and receptors are expressed in a human glioma cell line. 1989.Cancer Res., 50: 2524-2529, 1990. 16. Vlodavsky, I., Folkman, J., and Sullivan. R. Endothelial cell-derived basic
12. Libermann, T. A., Friese!, R., Jaye, M., et al. An angiogenic growth factor fibroblast growth factor: synthesis and deposition into subendothelial extra-is expressed in human glioma cells. EMBO J., 6: 1627-1632. 1987. cellular matrix. Proc. Nati. Acad. Sci. USA, 84: 2292-2296, 1987.
5765
on June 8, 2020. © 1991 American Association for Cancer Research. cancerres.aacrjournals.org Downloaded from
1991;51:5760-5765. Cancer Res David F. Stefnik, Laila R. Rizkalla, Anuradha Soi, et al. Glioblastoma MultiformeAcidic and Basic Fibrolast Growth Factors Are Present in
Updated version
http://cancerres.aacrjournals.org/content/51/20/5760
Access the most recent version of this article at:
E-mail alerts related to this article or journal.Sign up to receive free email-alerts
Subscriptions
Reprints and
To order reprints of this article or to subscribe to the journal, contact the AACR Publications
Permissions
Rightslink site. Click on "Request Permissions" which will take you to the Copyright Clearance Center's (CCC)
.http://cancerres.aacrjournals.org/content/51/20/5760To request permission to re-use all or part of this article, use this link
on June 8, 2020. © 1991 American Association for Cancer Research. cancerres.aacrjournals.org Downloaded from
