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Tumor Biology |
Vß3 Promotes M21 Melanoma Growth in Human Skin by Regulating Tumor Cell Survival1
University of Southern California School of Medicine, Department of Biochemistry and Molecular Biology, Norris Cancer Center, Los Angeles, California 90033 [E. P., P. C. B.]; Department of Immunology, Pathology, Microbiology, and Infectious Diseases, Karolinska Institute, Huddinge University Hospital, SE-14186 Huddinge, Sweden [S. S.]; Department of Immunology, The Scripps Research Institute, La Jolla, California 92037 [T. L. v. S., A. M. P. M., D. A. C.]; and Merck Farma y Quimica, Laboratorio de Bioinvestigacion, Barcelona, Spain [F. M., J. P.]
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ABSTRACT |
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 Top ABSTRACT INTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
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Vß3 plays a critical role in M21 melanoma tumor survival within human skin by a mechanism independent of its known role in angiogenesis. Antagonists of Vß3 blocked melanoma growth by inducing tumor apoptosis. Moreover, M21 melanoma cell interactions with denatured collagen, a known ligand for Vß3, caused a 5-fold increase in the relative Bcl-2:Bax ratio, an event thought to promote cell survival. Importantly, denatured collagen colocalized with Vß3-expressing melanoma cells in human tumor biopsies, suggesting that Vß3 interaction with denatured collagen may play a critical role in melanoma tumor survival in vivo. |
INTRODUCTION |
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TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
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The integrin family of cell adhesion receptors is known to mediate cellular interactions with the ECM (7)
. Interestingly, ligation of v and ß1 integrins may promote cell survival in vitro (8
, 9)
. Moreover, reports indicate that expression of Vß3 correlates with the vertical growth phase of human melanoma, suggesting that this integrin plays an important role in melanoma progression (10)
. However, little information is available concerning the potential mechanisms mediating these processes.
In this report, we provide evidence that Vß3 plays a critical role in melanoma cell survival within true human skin, where cutaneous melanomas typically arise. Furthermore, we have identified denatured collagen as a physiologically relevant Vß3 ligand present in human melanoma biopsies. Finally, we provide evidence for a mechanism by which Vß3 may regulate human melanoma growth in vivo by interaction with denatured collagen.
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MATERIALS AND METHODS |
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TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
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Vß3, Mabs 17E6 and ID7 directed to v and ß3, and Mab AP3 directed to ß3 have been described previously (11, 12, 13)
. Mab W6/32 (anti-MHC class I) was obtained from the American Type Culture Collection (Rockville, MD). Mab 5G3 directed to LI-CAM has been described previously (14)
. Mab HUI77 directed to denatured collagens was developed by subtractive immunization.5
Polyclonal antibodies Ab-1 and Ab-2 directed to Bcl-2 and Bax, respectively, were obtained from Calbiochem (La Jolla, CA). Mab 4062 directed to Ki67 was obtained from Chemicon (Temecula, CA). Goat antimouse and goat antirabbit FITC and rhodamine-conjugated IgGs were from BioSource International (Camarillo, CA). Bacterial collagenase was obtained from Worthington Biochemical Corp. (Freehold, NJ). OCT embedding compound was obtained from VWR Scientific Products (San Franscisco, CA). The ApopTag Apoptosis Detection Kit was obtained from Oncor (Gaithersburg, MD).
Cells and Cell Culture.
Human melanoma cell line M21 was obtained from D. L. Morton (University of California, Los Angeles, CA). M21 variants M21L (v negative), M21L4 (v positive), and M21L12 (v-negative transfection control) were described previously (15)
. Cells were maintained in RPMI 1640 supplemented with 10% fetal bovine serum, 2 mM L-glutamine, and Pen-Strep.
Tumor Growth Assays.
Tumor growth assays were performed essentially as described previously (16)
. Briefly, subconfluent cultures of M21 melanoma cell variants were harvested and washed three times with serum-free RPMI 1640. Melanoma cells (1 x 106) were injected s.c. into the flanks of 6-week-old SCID or nude mice. In the human/SCID mouse chimeric model, fresh human neonatal foreskins were obtained from the Cooperative Human Tissue Network (Cleveland, OH). SCID mice were prepared for surgical transplantation of human skin as described previously (17)
. Tumors were allowed to propagate for up to 37 days. Tumor growth was monitored by measuring the dimensions (length and width) of the growing tumors with calipers. Mabs were injected i.p. at a concentration of 250 µg/mouse. Antibody treatments were given three times per week. Mice were sacrificed, and tumors were resected and snap-frozen in liquid nitrogen for further analysis.
Immunofluorescence Analysis of Tumor Tissue.
Tissue sections (4 µm) were fixed in acetone for 30 s and then stored at -70°C until use. For apoptosis analysis, sections were washed in 70% ethanol, followed by three washes with PBS, and blocked with 2.5% BSA. Tissues were then incubated with Mabs 5G3 anti-L1 (50 µg/ml) and HUI77 (100 µg/ml). Tissue sections were washed five times with PBS, followed by incubation with rhodamine and FITC-conjugated IgGs at a dilution of 1:400. ApopTag staining was performed according to the manufacturer’s instructions. As a second method for the detection of apoptosis, Tdt-mediated nick end labeling staining was performed with the Promega In Situ Cell Death Detection Kit according to the manufacturer’s instructions.
Flow Cytometric Analysis.
Single cell suspensions were prepared by bacterial collagenase digestion as described previously (16)
. The cells were washed three times with serum-free RPMI 1640 containing 1% BSA and fixed in 1% paraformaldehyde. The fixed cells were washed three times with PBS and stained with the ApopTag reagent according to the manufacturer’s instructions. Cell fluorescence was measured with a FACScan flow cytometer (Becton Dickinson, Mountain View, CA). Negative control gates were set by using cell suspensions incubated in the absence of Tdt enzyme.
Western Blot Analysis.
M21 and M21L tumors were washed three times with PBS and minced. The tumor mince was resuspended in lysis buffer containing 300 mM NaCl, 50 mM Tris, and 1.0% Triton X-100 (pH 7.5) and homogenized. Tumor lysates (100 µg) were separated by 15% SDS-PAGE. Proteins were transfered to nitrocellulose and probed with polyclonal antibodies Ab-1 (anti-Bcl-2) or Ab-2 (anti-Bax), followed by incubation with goat antirabbit peroxidase-labeled secondary antibody. Western blots were visualized by an enhanced chemiluminescence detection system according to the manufacturer’s instructions (Amersham Life Sciences, Arlington Heights, IL).
Cell-Ligand ELISA.
ELISA plates were coated with 50 µl of human native collagen type I, denatured collagen type I, fibronectin, laminin, or vitronectin at a concentration of 25 µg/ml for 18 h at 4°C. Wells were blocked with 1% BSA. Cultures of M21 or M21L cells were washed three times and incubated in serum-free RPMI 1640 for 24 h. Serum-starved cells were harvested and resuspended in modified adhesion buffer containing 0.5% BSA, 1.0 mM MgCl2, 0.2 mM CaCl2, and 0.2 mM MnCl2 in PBS (pH 7.5) at a concentration of 1 x 106 cells/ml. Fifty µl of cell suspensions were added to either BSA-coated or matrix-coated wells. Cells were allowed to attach for 5 h at 37°C in a humidified CO2 incubator. Lids were then removed, and the plates were placed in a 37°C dry incubator overnight. This procedure resulted in lysis of the cells and drying the cell lysates to the bottom of the wells. Plates were then washed, and ELISA was performed by standard procedures as described previously (18)
.
Statistical Analysis.
Statistical analysis was performed with the Stat works program for Macintosh computers. Data were analyzed for statistical significance using Student’s t test.
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RESULTS |
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TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
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Vß3 Antagonists Inhibit Human M21 Melanoma Growth in Vivo.v integrins correlates with enhanced melanoma growth (19)
. Thus, Vß3 expressed in human melanoma may contribute to tumor growth independently of its role in angiogenesis. To test this possibility, SCID mice were injected with Vß3-expressing M21 human melanoma cells, followed by injections with either function-blocking Vß3-specific Mab LM609 or AP3, a control Mab directed to ß3. As shown in Fig. 1A
, Mab LM609 inhibited M21 tumor growth, whereas control AP3 had little, if any, effect. To confirm these results, a second Vß3 blocking Mab (17E6) was evaluated in an independent model of tumor growth. As shown in Fig. 1B
, Mab 17E6 dramatically inhibited M21 tumor growth in nude mice, whereas control anti-ß3 Mab ID7 had no effect. Moreover, M21 tumor growth was not inhibited by systemic administration of the Vß5 function-blocking Mab P1F6 in similar experiments (data not shown). Importantly, the inhibition of tumor growth observed in SCID mice was not due to LM609 blocking angiogenesis, as has been reported in earlier studies, because LM609 does not react with murine Vß3 (16
, 20)
.
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Vß3 expression contributes to human M21 melanoma growth within human skin, we evaluated the growth of M21 melanoma cells in the human/SCID mouse chimeric model. As shown in Fig. 2A
, Vß3-expressing M21L4 cells formed large tumors. In contrast, Vß3-negative M21L12 cells showed minimal tumor growth. In fact, by 34 days, M21L4 tumors were, on average, 6-fold larger than M21L12 tumors (P < 0.009). After 20 days of incubation, Vß3-negative M21L12 cells began to establish measurable tumors. These findings suggest that whereas Vß3 plays a role in M21 melanoma tumor development, other integrins besides Vß3 are also likely contribute to this process. Previous studies suggest that once a critical mass of M21L melanoma cells was established in mice, the tumors grew at similar rates (19)
. Consistent with these results, once M21L12 cells establish tumor foci in the human skin, no significant difference in tumor cell proliferation could be detected by staining with a Mab directed to nuclear proliferation antigen Ki67 (data not shown). These findings suggest that the differences in tumor size may not be directly associated with proliferation rates, but rather with the early establishment of initial tumor foci.
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Vß3 Protects Human M21 Melanoma from Apoptosis within Full-thickness Human Skin.Vß3 has been shown to regulate cell survival in vitro (8
, 15)
. However, no information is known concerning whether this mechanism functions in tumors growing in human skin, where melanoma is typically found. Moreover, our results suggest that Vß3 expression may be a requirement for the establishment of early tumor foci. To examine this possibility, M21L4 and M21L12 cells were grown for 5 days within the human skin. These tissues were analyzed for apoptosis by costaining with ApoTag reagent and Mab 5G3 directed to human L1, which is highly expressed in M21 cells (data not shown). As shown in Fig. 2B
, M21L4 cells were detected within the human skin (top left panel) and exhibited little apoptosis (bottom left panel). In contrast, Vß3-negative M21L12 cells showed extensive cell death throughout the tumor foci (bottom right panel). To quantitate the extent of cell death, cell suspensions derived from these tumors were analyzed for apoptosis by flow cytometry. As shown in Fig. 2C
, cells from M21L12 tumors showed a dramatic increase in apoptosis as compared to cells from M21L4 tumors. In fact, M21L12 tumors showed a 3-fold increase in apoptosis, whereas cells from normal human skin in the absence of tumor cells showed little, if any, evidence of cell death (Fig. 2D.)
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Antagonists of Vß3 Induce Apoptosis of M21 Melanoma Tumors in Vivo.
Our findings indicate that a specific antagonist of Vß3 can block melanoma growth in vivo and, furthermore, that Vß3 plays an important role in melanoma survival within human skin. To confirm these observations, SCID mice were injected with M21L4 melanoma cells, followed by treatments with either control Mab W6/32 or Mab LM609. Tissues from control- and LM609-treated tumors were analyzed for apoptosis with the ApopTag reagent. As shown in Fig. 3A
, tumors from mice treated with LM609 exhibited extensive apoptosis as compared to tumors from W6/32-treated mice. Importantly, whereas some apoptotic cells were detected within the centers of both control- and LM609-treated tumors, only the LM609-treated tumors showed extensive apoptosis throughout the tumor, including the margins near the host-tumor interface. Similar results were obtained with function-blocking Mab 17E6 in the human/mouse chimeric model using an independent Tdt-mediated nick end labeling staining assay (data not shown).
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Vß3 has been reported to regulate the expression of Bcl-2 and Bax, proteins thought to modulate apoptosis (15)
. Moreover, studies have reported high levels of Bcl-2 expression within both human melanoma biopsies and cell lines (15
, 24)
. Therefore, we compared the expression of both Bcl-2 and Bax within M21 melanomas grown in SCID mice by Western blotting. As shown in Fig. 3B
(top panel), Bcl-2 was detected in Vß3-expressing M21 tumors, whereas little was found in M21L tumors. Conversely, Bax was detected in Vß3-negative M21L tumors, whereas M21 tumors failed to express detectable levels (Fig. 3B
, bottom panel). These findings demonstrate a high Bcl-2:Bax ratio in melanomas expressing Vß3, which is consistent with the possibility that ligation of Vß3 in these tumors may regulate Bcl-2 and Bax expression, thereby contributing to cell survival (15
, 25, 26, 27, 28)
. Importantly, some Vß3-negative melanoma cells eventually established small tumors, suggesting that other mechanisms in addition to the Bcl-2:Bax ratio are likely to contribute to melanoma survival.
ECM-mediated Regulation of Bcl-2 and Bax within Vß3-expressing Melanoma Cells.
Expression of Bcl-2 and Bax may be regulated by integrin-mediated interactions with the ECM (15
, 29)
. Therefore, we examined the expression of Bcl-2 and Bax in M21 and M21L melanoma cells after interactions with Vß3-specific ECM ligands or controls. As shown in Fig. 4A
, little, if any, change in Bcl-2 expression was detected in M21 or M21L cells attached to either the Vß3-dependent or control ECM ligands. In contrast, Bax expression was reduced 2- and 4-fold in M21 cells attached to Vß3 -directed ligands vitronectin and denatured collagen, respectively (Fig. 4B)
. Interestingly, these results are consistent with the reduction in Bax expression observed in Vß3-expressing M21 tumors in vivo. In addition, M21 cell attachment to native collagen also reduced Bax expression, suggesting a role for ß1 integrins in this response. Importantly, no change in Bax expression could be detected in Vß3-negative M21L cells when attached to any of the ligands tested. These results implicate ligation of Vß3 in the regulation of Bax expression because M21 cells predominately use Vß3 in binding to vitronectin and denatured collagen (data not shown). Previous studies have suggested that a high Bcl-2:Bax expression ratio is associated with increased cell survival (15
, 25, 26, 27)
. As shown in Fig. 4C
, M21 cell attachment to vitronectin and denatured collagen induced a 3- and 5-fold increase in the mean Bcl-2:Bax ratio, respectively, whereas attachment to other ligands showed only a minimal change, if any. These results suggest that melanoma cell interaction with Vß3-directed ligands may promote a high Bcl-2:Bax ratio that is thought to contribute to cell survival.
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Vß3-directed ligand vitronectin has been detected in association with some tumors (29)
, collagen represents the majority of the ECM components within the dermal regions of human skin, where cutaneous melanomas typically arise. Moreover, M21 melanoma cell ligation of denatured collagen showed a 5-fold increase in the Bcl-2:Bax ratio compared to a 3-fold increase for interactions with vitronectin. Because denatured collagen is a ligand for Vß3 and because Vß3 ligation may regulate melanoma cell survival, we examined the possibility that denatured collagen was generated during human melanoma tumor growth in vivo. Tissue sections from both human melanoma biopsies and M21 tumors grown within full-thickness human skin were costained with anti-v polyclonal antibody and HUI77, a Mab specifically directed to denatured collagen but not to native collagen. As shown in Fig. 5
, denatured collagen (green) was detected and shown to colocalize (yellow) with Vß3-expressing melanoma cells (red) within human tumor biopsies (left panels). Moreover, similar results were observed with M21 melanoma cells grown within full-thickness human skin (right panels). Importantly, few if any melanoma cells observed within these tumors showed evidence of apoptosis when associated with denatured collagen after costaining experiments with ApopTag and Mab HUI77 (data not shown). Taken together, these findings suggest that the triple helical collagen within these human tumors is being selectively denatured, providing a physiologically relevant ligand for Vß3 during melanoma growth in vivo.
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DISCUSSION |
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TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
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Vß3 plays an important role in the survival of human M21 melanomas within full-thickness human skin. This contention is supported by the fact that melanoma cells lacking Vß3 exhibited extensive apoptosis within human skin. Furthermore, Vß3-negative M21L12 cells failed to establish measurable tumors for 20 days, as compared to 7 days for vß3-expressing melanomas. These findings suggest a critical role for Vß3 in the formation of melanoma foci within human skin.
Previous reports have correlated the expression of Vß3 with the vertical growth phase of melanoma progression (10)
. However, little information is available concerning the mechanisms by which Vß3 contributes to melanoma tumorgenicity. Here, we provide evidence for the first time that Vß3 can facilitate human M21 melanoma growth in true human skin by regulating melanoma cell survival. Our findings suggest that the reduction in tumorgenicity observed in Vß3-negative M21L tumors was likely associated with the inability of these tumor cells to interact with the Vß3-directed ligands necessary for survival and was not due to alterations in tumor proliferation. This notion is supported by the fact that no change in proliferation was detected between M21 and M21L tumors stained for the Ki67 proliferation antigen. In addition, no difference in proliferation rates could be detected between Vß3-negative or -positive M21 cells grown in culture (19)
. Finally, earlier studies indicate that once Vß3-positive or -negative M21 cells established tumor foci in a murine model, their proliferation rates were similar (19)
.
The formation and expansion of solid tumors likely depend on a balance between cell growth and cell death (23
, 27)
. Consistent with this hypothesis, our results indicate that melanoma cells lacking Vß3 begin to undergo programmed cell death, whereas Vß3-expressing cells exhibited little, if any, apoptosis. Moreover, systemic administration of functional blocking antibodies directed to Vß3 but not Vß5 blocked melanoma growth by inducing tumor apoptosis. Importantly, this inhibition of tumor growth was not a result of blocking angiogenesis because this antagonist does not react with Vß3 expressed on murine blood vessels (16
, 20)
. These findings are in agreement with Vß3 playing a critical role in melanoma cell survival in vivo. In this regard, cell survival has been suggested to be regulated in part by the expression of Bcl-2 and Bax (9
, 15
, 16
, 29)
. In fact, Yin et al. (28)
recently demonstrated that overexpression of Bax increased tumor cell apoptosis, thereby reducing tumorgenicity. These findings are consistent with the expression of Bax that we observed in M21L tumors grown in vivo that exhibited similar phenotypic characteristics. In addition, our results also indicate that Vß3-expressing M21 tumors exhibited a high relative Bcl-2:Bax ratio as compared to Vß3-negative M21L tumors. These data are in agreement with the ability of the vß3-expressing melanoma cells to interact with ECM components necessary for survival and the establishment of tumor foci. Thus, the possibility exists that melanoma cells lacking Vß3 fail to interact with Vß3-dependent ECM components and therefore begin to under go apoptosis. To this end, collagen is a major component of the dermal ECM of human skin (8)
. Moreover, many melanoma tumors have the capacity to proteolytically remodel their collagenous mircoenvironment by secreting collagen-degrading proteases (5
, 8 , 35)
. Importantly, denatured collagen has been shown to be recognized by integrin Vß3 (8
, 36)
. Thus, denatured collagen may provide a physiologically important ligand for Vß3 to facilitate melanoma cell survival. Here, we provide evidence for the first time that denatured collagen is generated in vivo and, more importantly, colocalizes with Vß3-expressing melanoma cells within human melanoma tumor biopsies. Significantly, few if any melanoma cells that were surrounded by denatured collagen exhibited any evidence of apoptosis. Furthermore, we demonstrate that Vß3-mediated melanoma cell interactions with denatured collagen in vitro caused a 5-fold increase in the Bcl-2:Bax ratio. Whereas it is likely that other mechanisms besides Vß3 and the relative expression of Bcl-2 and Bax also contribute to melanoma cell survival, it appears that vß3 is a critical receptor in this process. Taken together, these findings suggest a mechanism by which Vß3 expressed in melanoma cells may interact with denatured collagen, regulating the relative Bcl-2:Bax ratio, thereby contributing to melanoma cell survival.
In conclusion, our studies suggest that Vß3 plays a critical role in melanoma cell survival in human skin and, furthermore, that Vß3 antagonists represent a powerful new class of antitumor agents by virtue of their ability to disrupt tumor growth by inducing tumor cell apoptosis.
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ACKNOWLEDGMENTS |
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FOOTNOTES |
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1 Supported by NIH Grant R29 CA74132-01 and the Stop Cancer Foundation of Los Angeles, California (to P. C. B.). 
2 E. P. was supported in part by fellowships from the Medical Research Council of Canada and The Fonds de la Recherche en santé du Québec.
3 To whom requests for reprints should be addressed, at University of Southern California School of Medicine, Department of Biochemistry and Molecular Biology, Norris Cancer Center, Topping Tower Room 6409, 1441 Eastlake Avenue, Los Angeles, CA 90033. Phone: (323) 865-0510; Fax: (323) 865-0514; E-mail: pbrooks{at}hsc.usc.edu
4 The abbreviations used are: ECM, extracellular matrix; Mab, monoclonal antibody; Tdt, terminal deoxynucleotidyl transferase; SCID, severe combined immunodeficient.
5 J. Xu, D. Rodriguez, E. Petitclerc, and P. C. Brooks. Generation of Mabs specific for denatured collagen, manuscript in preparation.
Received 10/13/98. Accepted 4/ 2/99.
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REFERENCES |
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TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
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vß3 rescues melanoma cells from apoptosis in three-dimensional dermal collagen. Proc. Natl. Acad. Sci. USA, 91: 8856-8860, 1994.v-integrin antibody that blocks integrin function inhibits the development of a human melanoma in nude mice. J. Cell Sci., 108: 2825-2838, 1995.[Abstract]
vß3 during angiogenesis. J. Clin. Investig., 98: 426-433, 1996.[Medline]
vß3 antagonists promote tumor regression by inducing apoptosis of angiogenic blood vessels. Cell, 79: 1157-1164, 1994.[Medline]
v gene expression in human melanoma tumorgenicity. J. Clin. Investig., 89: 2018-2022, 1992.
vß3 blocks human breast cancer growth and angiogenesis in human skin. J. Clin. Investig., 96: 1815-1822, 1995.
vß5 integrin supports survival of cells on fibronectin and up-regulates Bcl-2 expression. Proc. Natl. Acad. Sci. USA, 92: 6161-6165, 1995.vß5 to promote tumor cell dissemination in vivo. J. Clin. Investig., 99: 1390-1398, 1997.[Medline]
vß5 mediates vitronectin-dependent adhesion of retinoic acid-differentiated neuroblastoma cells. Am. J. Pathol., 150: 1631-1646, 1997.[Abstract]
vß3 integrin in human melanoma cell invasion. Proc. Natl. Acad. Sci. USA, 89: 1557-1561, 1992.vß3 binds to denatured collagen type I through RGD sites. Biochem. Biophys. Res. Commun., 182: 1025-1031, 1992.[Medline]
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G. P. Pidgeon, K. Tang, Y. L. Cai, E. Piasentin, and K. V. Honn Overexpression of Platelet-type 12-Lipoxygenase Promotes Tumor Cell Survival by Enhancing {alpha}v{beta}3 and {alpha}v{beta}5 Integrin Expression Cancer Res., July 15, 2003; 63(14): 4258 - 4267. [Abstract] [Full Text] [PDF]
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 M. F. Burbridge, V. Venot, P. J. Casara, F. Perron-Sierra, J. A. Hickman, and G. C. Tucker Decrease in Survival Threshold of Quiescent Colon Carcinoma Cells in the Presence of a Small Molecule Integrin Antagonist Mol. Pharmacol., June 1, 2003; 63(6): 1281 - 1288. [Abstract] [Full Text] [PDF]
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B. Govindarajan, X. Bai, C. Cohen, H. Zhong, S. Kilroy, G. Louis, M. Moses, and J. L Arbiser Malignant Transformation of Melanocytes to Melanoma by Constitutive Activation of Mitogen-activated Protein Kinase Kinase (MAPKK) Signaling J. Biol. Chem., March 7, 2003; 278(11): 9790 - 9795. [Abstract] [Full Text] [PDF]
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 J. H. Wang, B. J. Manning, Q. D. Wu, S. Blankson, D. Bouchier-Hayes, and H. P. Redmond Endotoxin/Lipopolysaccharide Activates NF-{kappa}B and Enhances Tumor Cell Adhesion and Invasion Through a {beta}1 Integrin-Dependent Mechanism J. Immunol., January 15, 2003; 170(2): 795 - 804. [Abstract] [Full Text] [PDF]
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M. Hangai, N. Kitaya, J. Xu, C. K. Chan, J. J. Kim, Z. Werb, S. J. Ryan, and P. C. Brooks Matrix Metalloproteinase-9-Dependent Exposure of a Cryptic Migratory Control Site in Collagen is Required before Retinal Angiogenesis Am. J. Pathol., October 1, 2002; 161(4): 1429 - 1437. [Abstract] [Full Text] [PDF]
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E. Geissinger, C. Weisser, P. Fischer, M. Schartl, and C. Wellbrock Autocrine Stimulation by Osteopontin Contributes to Antiapoptotic Signalling of Melanocytes in Dermal Collagen Cancer Res., August 15, 2002; 62(16): 4820 - 4828. [Abstract] [Full Text] [PDF]
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 M. L. Wahl, J. A. Owen, R. Burd, R. A. Herlands, S. S. Nogami, U. Rodeck, D. Berd, D. B. Leeper, and C. S. Owen Regulation of Intracellular pH in Human Melanoma: Potential Therapeutic Implications Mol. Cancer Ther., June 1, 2002; 1(8): 617 - 628. [Abstract] [Full Text] [PDF]
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 D. G. Stupack and D. A. Cheresh Get a ligand, get a life: integrins, signaling and cell survival J. Cell Sci., January 10, 2002; 115(19): 3729 - 3738. [Abstract] [Full Text] [PDF]
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R. A. Sturm, K. Satyamoorthy, F. Meier, B. B. Gardiner, D. J. Smit, B. Vaidya, and M. Herlyn Osteonectin/SPARC Induction by Ectopic {beta}3 Integrin in Human Radial Growth Phase Primary Melanoma Cells Cancer Res., January 1, 2002; 62(1): 226 - 232. [Abstract] [Full Text] [PDF]
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J. Xu, D. Rodriguez, E. Petitclerc, J. J. Kim, M. Hangai, S. M. Yuen, G. E. Davis, and P. C. Brooks Proteolytic exposure of a cryptic site within collagen type IV is required for angiogenesis and tumor growth in vivo J. Cell Biol., September 3, 2001; 154(5): 1069 - 1080. [Abstract] [Full Text] [PDF]
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J. Brummer, A. Ebrahimnejad, R. Flayeh, U. Schumacher, T. Loning, A.-M. Bamberger, and C. Wagener cis Interaction of the Cell Adhesion Molecule CEACAM1 with Integrin {beta}3 Am. J. Pathol., August 1, 2001; 159(2): 537 - 546. [Abstract] [Full Text]
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C. C. Kumar, M. Malkowski, Z. Yin, E. Tanghetti, B. Yaremko, T. Nechuta, J. Varner, M. Liu, E. M. Smith, B. Neustadt, et al. Inhibition of Angiogenesis and Tumor Growth by SCH221153, a Dual {{alpha}}v{beta}3 and {{alpha}}v{beta}5 Integrin Receptor Antagonist Cancer Res., March 1, 2001; 61(5): 2232 - 2238. [Abstract] [Full Text]
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O. Salvucci, M. Carsana, I. Bersani, G. Tragni, and A. Anichini Antiapoptotic Role of Endogenous Nitric Oxide in Human Melanoma Cells Cancer Res., January 1, 2001; 61(1): 318 - 326. [Abstract] [Full Text]
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Y. Maeshima, P. C. Colorado, and R. Kalluri Two RGD-independent alpha vbeta 3 Integrin Binding Sites on Tumstatin Regulate Distinct Anti-tumor Properties J. Biol. Chem., July 28, 2000; 275(31): 23745 - 23750. [Abstract] [Full Text] [PDF]
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D.-Q. Zheng, A. S. Woodard, G. Tallini, and L. R. Languino Substrate Specificity of alpha vbeta 3 Integrin-mediated Cell Migration and Phosphatidylinositol 3-Kinase/AKT Pathway Activation J. Biol. Chem., August 4, 2000; 275(32): 24565 - 24574. [Abstract] [Full Text] [PDF]
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G. A. McMahon, E. Petitclerc, S. Stefansson, E. Smith, M. K. K. Wong, R. J. Westrick, D. Ginsburg, P. C. Brooks, and D. A. Lawrence Plasminogen Activator Inhibitor-1 Regulates Tumor Growth and Angiogenesis J. Biol. Chem., August 31, 2001; 276(36): 33964 - 33968. [Abstract] [Full Text] [PDF]
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 P. Henriet, Z.-D. Zhong, P. C. Brooks, K. I. Weinberg, and Y. A. DeClerck Contact with fibrillar collagen inhibits melanoma cell proliferation by up-regulating p27KIP1 PNAS, August 29, 2000; 97(18): 10026 - 10031. [Abstract] [Full Text] [PDF]
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