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Association between CCNE1 variants and bladder cancer

Supplementary Figure 1: Electrophoretic mobility shift assays (EMSA) for CCNE1 SNPs rs8102137 and rs7257330. Supplementary Figure 2: Alignment of cyclin E protein isoforms - WT1, WT2 and ES and ET. Supplementary Figure 3: Functional analysis of cyclin E isoforms.Supplementary Table 1: Description of sub-studies included in NCI-GWAS1 and GWAS2 of bladder cancer. Supplementary Table 2: Characteristics of bladder tissue samples used for mRNA expression analysis. Supplementary Table 3: PCR primers, genotyping and gene expression assays, EMSA probes and antibodies. Supplementary Table 4: Bladder cancer stage and grade information for patients in the combined GWAS1+2 set. Supplementary Table 6: Association with bladder cancer risk with mutual adjustment for CCNE1 variants. Supplementary Table 7: Association with bladder cancer risk for CCNE1 variants previously associated with other cancers and for two non-synonymous coding variants. Supplementary Table 8: Association between cyclin E protein expression (IHC scores), bladder cancer patient characteristics and CCNE1 variants.

von Hippel-Lindau (VHL) disease is an autosomal-dominant tumor predisposition syndrome characterized by the development of highly vascularized tumors and cysts. LOH of the VHL gene results in aberrant upregulation of hypoxia-inducible factors (HIF) and has been associated with tumor formation. Hemangioblastomas of the central nervous system and retina represent the most prevalent VHL-associated tumors, but no VHL animal model has reproduced retinal capillary hemangioblastomas (RCH), the hallmark lesion of ocular VHL. Here we report our work in developing a murine model of VHL-associated RCH by conditionally inactivating Vhl in a hemangioblast population using a Scl-Cre-ERT2 transgenic mouse line. In transgenic mice carrying the conditional allele and the Scl-Cre-ERT2 allele, 64% exhibited various retinal vascular anomalies following tamoxifen induction. Affected Vhl-mutant mice demonstrated retinal vascular lesions associated with prominent vasculature, anomalous capillary networks, hemorrhage, exudates, and localized fibrosis. Histologic analyses showed RCH-like lesions characterized by tortuous, dilated vasculature surrounded by “tumorlet” cell cluster and isolated foamy stromal cells, which are typically associated with RCH. Fluorescein angiography suggested increased vascular permeability of the irregular retinal vasculature and hemangioblastoma-like lesions. Vhl deletion was detected in “tumorlet” cells via microdissection. Our findings provide a phenotypic recapitulation of VHL-associated RCH in a murine model that may be useful to study RCH pathogenesis and therapeutics aimed at treating ocular VHL. Significance: This study describes a model that phenotypically recapitulates a form of retinal pathogenesis that is driven by genetic loss of the VHL tumor suppressor, providing a useful tool for its study and therapeutic intervention. Cancer Res; 78(5); 1266–74. ©2018 AACR.

A genome-wide association study (GWAS) of bladder cancer identified a genetic marker rs8102137 within the 19q12 region as a novel susceptibility variant. This marker is located upstream of the CCNE1 gene, which encodes cyclin E, a cell-cycle protein. We performed genetic fine-mapping analysis of the CCNE1 region using data from two bladder cancer GWAS (5,942 cases and 10,857 controls). We found that the original GWAS marker rs8102137 represents a group of 47 linked SNPs (with r2 ≥ 0.7) associated with increased bladder cancer risk. From this group, we selected a functional promoter variant rs7257330, which showed strong allele-specific binding of nuclear proteins in several cell lines. In both GWASs, rs7257330 was associated only with aggressive bladder cancer, with a combined per-allele OR = 1.18 [95% confidence interval (CI), 1.09–1.27, P = 4.67 × 10−5] versus OR = 1.01 (95% CI, 0.93–1.10, P = 0.79) for nonaggressive disease, with P = 0.0015 for case-only analysis. Cyclin E protein expression analyzed in 265 bladder tumors was increased in aggressive tumors (P = 0.013) and, independently, with each rs7257330-A risk allele (Ptrend = 0.024). Overexpression of recombinant cyclin E in cell lines caused significant acceleration of cell cycle. In conclusion, we defined the 19q12 signal as the first GWAS signal specific for aggressive bladder cancer. Molecular mechanisms of this genetic association may be related to cyclin E overexpression and alteration of cell cycle in carriers of CCNE1 risk variants. In combination with established bladder cancer risk factors and other somatic and germline genetic markers, the CCNE1 variants could be useful for inclusion into bladder cancer risk prediction models. Cancer Res; 74(20); 5808–18. ©2014 AACR.

Angiogenesis and inflammation are important therapeutic targets in non-small cell lung cancer (NSCLC). It is well known that proteolysis mediated by matrix metalloproteinases (MMPs) promotes angiogenesis and inflammation in the tumor microenvironment. Here, the effects of the MMP inhibitor TIMP-2 on NSCLC inflammation and angiogenesis were evaluated in TIMP-2-deficient (timp2-/-) mice injected subcutaneously (SC) with Lewis lung carcinoma cells and compared with the effects on tumors in wild-type mice. TIMP-2-deficient mice demonstrated increased tumor growth, enhanced expression of angiogenic marker αvβ3 in tumor and endothelial cells, and significantly higher serum vascular endothelial growth factor-A levels. Tumor-bearing timp2-/- mice showed a significant number of inflammatory cells in their tumors, upregulation of inflammation mediators, nuclear factor-kappaB, and Annexin A1, as well as higher levels of serum interleukin (IL)-6. Phenotypic analysis revealed an increase in myeloid-derived suppressor cell (MDSC) cells (CD11b+ and Gr-1+) that coexpressed vascular-endothelial-growth factor receptor 1 (VEGF-R1) and elevated MMP activation present in tumors and spleens from timp2-/- mice. Furthermore, TIMP-2-deficient tumors upregulated expression of the immunosuppressing genes controlling MDSC growth, IL-10, IL-13, IL-11, and chemokine ligand (CCL-5/RANTES), and decreased interferon-γ and increased CD40L. Moreover, forced TIMP-2 expression in human lung adenocarcinoma A-549 resulted in a significant reduction of MDSCs recruited into tumors, as well as suppression of angiogenesis and tumor growth. The increase in MDSCs has been linked to cancer immunosuppression and angiogenesis. Therefore, this study supports TIMP-2 as a negative regulator of MDSCs with important implications for the immunotherapy and/or antiangiogenic treatment of NSCLC.

The presence of bcl-2 in myeloid leukemias has been associated with a decrease in therapy-induced apoptosis, reduced patient survival and in vitro autonomous growth of leukemic cells. The present study focuses on the quantitation of resistance to increasing doses of 1-beta-d-arabinofuranosylcytosine (Ara-C) by using hematological tumors expressing different levels of bcl-2. Scanning densitometry of Western blots demonstrated that the myeloid U-937 cells express low levels of bcl-2 (RD = 0.008), whereas the follicular lymphoma RL-7 expressed very high levels (RD = 3.084). Colony formation was also examined following incubation with Ara-C and RL-7 cells demonstrated a higher clonogenic survival (LD50 = 0.5 microns) when compared with U-937 cells (LD50 = 0.005 microM). Similarly, the level of bcl-2 expression in each cell line was also related to apoptosis with U-937 cells demonstrating increased DNA fragmentation when compared with RL-7 cells. To further evaluate the effect of upregulated bcl-2 on Ara-C treatment, U-937 cells were transfected with a retroviral vector carrying the murine bcl-2 or vector alone. Upregulation of bcl-2 by myeloid leukemic cells increased the resistance by 3 logs to Ara-C when comparing LD50 values from clonogenic assays, and decreased apoptosis by at least 3 logs when measuring dUTP positive cells by flow cytometry.

CD97, a membrane protein expressed at high levels on inflammatory cells and some carcinomas, is a member of the adhesion G protein–coupled receptor family, whose members have bipartite structures consisting of an extracellular peptide containing adhesion motifs noncovalently coupled to a class B 7-transmembrane domain. CD97α, the extracellular domain of CD97, contains 3 to 5 fibrillin class 1 epidermal growth factor (EGF)–like repeats, an Arg-Gly-Asp (RGD) tripeptide, and a mucin stalk. We show here that CD97α promotes angiogenesis in vivo as demonstrated with purified protein in a directed in vivo angiogenesis assay (DIVAA) and by enhanced vascularization of developing tumors expressing CD97. These data suggest that CD97 can contribute to angiogenesis associated with inflammation and tumor progression. Strong integrin α5β1 interactions with CD97 have been identified, but αvβ3 also contributes to cell attachment. Furthermore, soluble CD97 acts as a potent chemoattractant for migration and invasion of human umbilical vein endothelial cells (HUVECs), and this function is integrin dependent. CD97 EGF-like repeat 4 is known to bind chondroitin sulfate. It was found that coengagement of α5β1 and chondroitotin sulfate proteoglycan by CD97 synergistically initiates endothelial cell invasion. Integrin α5β1 is the first high-affinity cellular counterreceptor that has been identified for a member within this family of adhesion receptors.

We have found through ex vivo and in vivo angiogenesis models that the adrenomedullin gene-related peptide, proadrenomedullin NH2-terminal 20 peptide (PAMP), exhibits a potent angiogenic potential at femtomolar concentrations, whereas classic angiogenic factors such as vascular endothelial growth factor and adrenomedullin mediate a comparable effect at nanomolar concentrations. We found that human microvascular endothelial cells express PAMP receptors and respond to exogenous addition of PAMP by increasing migration and cord formation. Exposure of endothelial cells to PAMP increases gene expression of other angiogenic factors such as adrenomedullin, vascular endothelial growth factor, basic fibroblast growth factor, and platelet-derived growth factor C. In addition, the peptide fragment PAMP(12-20) inhibits tumor cell–induced angiogenesis in vivo and reduces tumor growth in xenograft models. Together, our data demonstrate PAMP to be an extremely potent angiogenic factor and implicate this peptide as an attractive molecular target for angiogenesis-based antitumor therapy.

Tissue inhibitors of metalloproteinases (TIMPs) suppress matrix metalloproteinase (MMP) activity critical for extracellular matrix turnover associated with both physiologic and pathologic tissue remodeling. We demonstrate here that TIMP-2 abrogates angiogenic factor-induced endothelial cell proliferation in vitro and angiogenesis in vivo independent of MMP inhibition. These effects require alpha 3 beta 1 integrin-mediated binding of TIMP-2 to endothelial cells. Further, TIMP-2 induces a decrease in total protein tyrosine phosphatase (PTP) activity associated with beta1 integrin subunits as well as dissociation of the phosphatase SHP-1 from beta1. TIMP-2 treatment also results in a concomitant increase in PTP activity associated with tyrosine kinase receptors FGFR-1 and KDR. Our findings establish an unexpected, MMP-independent mechanism for TIMP-2 inhibition of endothelial cell proliferation in vitro and reveal an important component of the antiangiogenic effect of TIMP2 in vivo.

One of the major problems in angiogenesis research remains the lack of suitable methods for quantifying the angiogenic response in vivo. We describe the development and application of the directed in vivo angiogenesis assay (DIVAA) and demonstrated that it is reproducible and quantitative. This assay consists of subcutaneous implantation of semiclosed silicone cylinders (angioreactors) into nude mice. Angioreactors are filled with only 18 micro l of extracellular matrix premixed with or without angiogenic factors. Vascularization within angioreactors is quantified by the intravenous injection of fluorescein isothiocyanate (FITC)-dextran before their recovery, followed by spectrofluorimetry. Angioreactors examined by immunofluorescence show cells and invading angiogenic vessels at different developmental stages. The minimally detectable angiogenic response requires 9 days after implantation and/=50 ng/ml (P0.01) of either fibroblast growth factor-2 or vascular endothelial growth factor. Characterization of this assay system demonstrates that the FITC-labeled dextran quantitation is highly reproducible and that levels of FITC-dextran are not significantly influenced by vascular permeability. DIVAA allows accurate dose-response analysis and identification of effective doses of angiogenesis-modulating factors in vivo. TNP-470 potently inhibits angiogenesis (EC(50) = 88 pmol/L) induced by 500 ng/ml of fibroblast growth factor-2. This inhibition correlates with decreased endothelial cell invasion. DIVAA efficiently detects differences in anti-angiogenic potencies of thrombospondin-1 peptides (25 micro mol/L) and demonstrates a partial inhibition of angiogenesis ( approximately 40%) in a matrix metalloprotease (MMP)-2-deficient mouse compared with that in wild-type animals. Zymography of angioreactors from MMP-deficient and control animals reveals quantitative changes in MMP expression. These results support DIVAA as an assay to compare potencies of angiogenic factors or inhibitors, and for profiling molecular markers of angiogenesis in vivo.

Overexpression of manganese superoxide dismutase (MnSOD) has been postulated as one possible mechanism of protection from oxidative damage and free radicals. Doxorubicin treatment induces oxygen free radicals, leading to cytotoxicity and myelosuppression. The present study was performed to determine whether over-expression of MnSOD may play a role in resistance to doxorubicin. Retroviral constructs having the human MNSOD gene in the sense orientation and the neomycin phosphotransferase gene (NEOR) as a selectable marker were transduced into the human melanoma cell line A375 and the human histiocytic lymphoma cell line U937. Stably transduced A375 and U937 cells were subjected to 10-100 ng/ml doxorubicin for 24 h and compared with doxorubicin-treated A375 and U937 cells transduced with vector only. A colony forming assay was used to determine cell viability in semi-solid medium. Results demonstrated that wild-type A375 and U937 cells display low levels of endogenous MnSOD mRNA and protein, and are sensitive to doxorubicin treatment. In contrast, A375 and U937 cells transduced with the MNSOD gene consistently demonstrate increased colony formation in the presence of increasing concentrations of doxorubicin. MnSOD-transduced A375 and U937 cells also demonstrate increased MnSOD mRNA and protein levels when compared with wild type or those cells transduced with vector only. These results indicate that overexpression of MnSOD can enhance resistance to doxorubicin treatment.

Background: Adrenomedullin is a secreted peptide hormone with multiple activities. Several reports have indicated that adrenomedullin may be involved in tumor survival, but this has not been directly shown. Here we evaluate the in vitro and in vivo effects of adrenomedullin overexpression in human breast cancer cells. Methods: The human breast cancer cell lines T47D and MCF7, both of which express low basal levels of adrenomedullin, were stably transfected with an expression construct that contained the coding region of the human adrenomedullin gene or with empty expression vector. Properties of the transfected cells were assessed by proliferation and apoptosis assays, in vitro and in vivo angiogenesis assays, cell migration experiments, and xenograft implants. The effect of synthetic adrenomedullin on human ovarian (ECV) cancer cell motility was also tested. Western blot analysis was used to compare expression levels of several genes whose products are associated with cell growth and regulation of apoptosis. Results: T47D and MCF7 cells transfected with the adrenomedullin construct both expressed high levels of adrenomedullin mRNA and protein. Compared with cells transfected with empty vector, cells that overexpressed adrenomedullin displayed a more pleiotropic morphology, an increased angiogenic potential both in vitro and in vivo, and less apoptosis after serum deprivation. T47D and MCF7 cells did not display measurable motility, but ECV ovarian cancer cells treated with synthetic adrenomedullin were more motile than saline-treated ECV cells. Adrenomedullin-overexpressing T47D cells had higher levels of proteins involved in oncogenic signal transduction pathways (such as Ras, Raf, PKC, and MAPKp49) and lower levels of pro-apoptotic proteins (such as Bax, Bid, and caspase 8) than T47D cells transfected with empty vector. In a preliminary in vivo experiment, three of 10 nude mice injected with adrenomedullin-overexpressing T47D cells developed xenograft tumors, whereas none of the 10 nude mice injected with cells carrying the empty plasmid developed tumors. Conclusions: These results further support the role of adrenomedullin as a survival factor for tumors. Development of physiologically efficient inhibitors of adrenomedullin may prove useful in the clinical management of cancer. [J Natl Cancer Inst 2002;94:1226–37]

Purpose: von Hippel-Lindau disease (VHL) is an autosomal dominant condition that features a constellation of cysts or highly vascularized tumors due to loss of heterozygosity (LOH) of the VHL gene, resulting in deregulated hypoxia-induced factors (HIFs). Clinical manifestations of VHL include hemangioblastomas in the central nervous system and retina. To date, no VHL animal model has reproduced retinal capillary hemangioblastomas (RCH), the hallmark lesion of ocular VHL. The RCHs may arise from arrested hemangioblast progenitor cells, with VHL LOH in the tumor stroma. The stem cell leukemia (SCL) gene encodes a basic helix-loop-helix (bHLH) transcription factor, a critical regulator of hematopoiesis and vasculogenesis. We aim to generate a murine model of VHL-associated RCH by conditionally inactivating Vhl in a hemangioblast progenitor population with the angioblast-specific Cre line, (SCL) Cre-ERt2. Methods: We established a genetic mouse model in which the inducible Vhl gene is specifically “knocked-out” in angioblast cells using the stem cell leukemia (SCL) Cre-ERt2 transgenic mice. Two-week-old SCL-CreERt2;Vhl-F/F mice were administrated tamoxifen (2mg/40g body weight) for 5 consecutive days to activate the Cre recombinase that induces Vhl deletion in angioblast-derived cells. Fundoscopy was done monthly to detect retinal lesions. Fluorescein angiography (FA) was performed on affected mice. All retinas were analyzed by histology at 4 months of age. Genome typing of the Vhl conditional KO allele was conducted in retinal lesions using microdissection, nest-PCR and Sanger sequencing. Results: About 64% (18/28) of the transgenic mice exhibited various retinal vascular defects following induction. Affected mice demonstrated retinal vascular lesions that were variably associated with prominent vessels, anomalous capillary networks, hemorrhage, exudates, and localized fibrosis. FA revealed vascular leakage from the lesions. Histological analyses showed RCH-like lesions of tortuous, dilated vessels surrounded by “tumorlet” cells, isolated foamy stromal cells, and glia, classically found in RCH. Vhl LOH was detected in the tumor-like area as verified by sequencing. Conclusion: This is the first demonstration of VHL-associated RCH in a transgenic mouse model. This model may be useful for studying RCH pathogenesis, including HIF-dependent and HIF-independent pathways, and for testing potential therapies. Citation Format: Herui Wang, Qi Zhang, Lijin Dong, Liliana Guedez, Stanley Park, Yujuan Wang, Shida Chen, Chun Gao, Wai T. Wong, Henry Wiley, Emily Chew, Chi-Chao Chan, Zhengping Zhuang. A murine model of von Hippel-Lindau associated retinal hemangioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1851. doi:10.1158/1538-7445.AM2017-1851

Epstein-Barr virus (EBV)-positive Burkitt’s lymphoma cells and EBV-infected B cells elicit humoral factors that inhibit tumor-induced angiogenesis, resulting in tumor necrosis and regression. Of the chemokine factors identified in association with this growth behavior, none have induced complete tumor regression. We have previously identified tissue inhibitors of metalloproteinase (TIMP)-1 in various B cell lymphoma cell lines. Here we show that induction of TIMP-1 expression in an EBV-negative Burkitt’s lymphoma cell line results in a biphasic, in vivo tumor growth pattern in the nude mouse that is essentially identical to EBV-positive Burkitt’s lymphoma cell lines. The initial effect of TIMP-1 is to enhance tumor growth, consistent with the reported anti-apoptotic effect of TIMP-1 on B cell growth. Tumor necrosis and regression then follow the initial period of rapid, increased tumor growth. Only microscopic foci of residual, proliferating tumor cells are observed on biopsy of the tumor site. This latter effect is mediated by TIMP-1 inhibition of an angiogenic response within the developing tumor mass, as demonstrated by immunostaining and microvessel counts. These findings suggest that TIMP-1 is an important mediator of the in vivo growth properties of EBV-positive Burkitt’s lymphoma.

Tissue inhibitors of metalloproteinases (TIMPs), first described as specific inhibitors of matrix metalloproteinases, have recently been shown to exert growth factor activities. It was previously demonstrated that TIMP-1 inhibits apoptosis in germinal center B cells and induces further differentiation. Interleukin-10 (IL-10) is reported as a vital factor for the differentiation and survival of germinal center B cells and is also a negative prognostic factor in non-Hodgkin lymphoma (NHL). However, the mechanism of IL-10 activity in B cells and the regulation of its expression are not well understood. IL-10 has been shown to up-regulate TIMP-1 in tissue macrophages, monocytes, and prostate cancer cell lines, but IL-10 modulation of TIMP-1 in B cells and the effect of TIMP-1 on IL-10 expression has not been previously studied. It was found that TIMP-1 expression regulates IL-10 levels in B cells and that TIMP-1 mediates specific B-cell differentiation steps. TIMP-1 inhibition of apoptosis is not IL-10 dependent. TIMP-1 expression in B-cell NHL correlates closely with IL-10 expression and with high histologic grade. Thus, TIMP-1 regulates IL-10 expression in B-cell NHL and, through the inhibition of apoptosis, appears responsible for the negative prognosis associated with IL-10 expression in these tumors.

The balance between the activities of matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) is an important control point during the turnover of the extracellular matrix. Previous studies have demonstrated that an uncontrolled rate of production of these proteins leads to various pathological conditions. Overexpression of MMPs by malignant cells can increase the invasive behavior of solid tumors and their metastatic potential. In an increasing number of reports, it has become evident that expression of MMPs and TIMPs is not restricted to solid tumors. Normal and malignant hematological cells also express these proteins and play a pivotal role in the hematological-cell physiology. In addition to modifying the extracellular matrix, MMPs and TIMPs exert other functions in hematological cells, including growth-factor activity, removal of cell-surface receptors, and autoimmunity. The goal of this review is to gather recent studies concerning the properties of MMPs and TIMPs in hematological cells, their regulation of gene expression, their cellular distribution, and their potential role in the pathogenesis of hematological disorders such as inflammation and neoplasia.

Purpose To determine the in vivo effect of doxycycline on choroidal angiogenesis and pterygium growth by using a choroidal neovascular (CNV) murine model, a directed in vivo angiogenesis assay (DIVAA) and a pterygium murine model. Design Experimental study. Participants Three murine models were investigated with 4 mice minimum per group and 22 maximum per group. Methods Mice received water with or without doxycycline. For the CNV, the neovascular lesion volume was determined in choroid-retinal pigment epithelial flat mounts using confocal microscopy 7 days after laser induction. For DIVAA, silicone capsules containing 10 000 human pterygium epithelial cells were implanted in the flanks of mice subcutaneously. After 11 days, neovascularization (NV) was quantified using spectrofluorometry after murine tail-vein injection of fluorescein isothiocyanate-labeled dextran. A pterygium epithelial cell model was developed by injecting 10 000 human pterygium epithelial cells in the nasal subconjunctival space in athymic nude mice. Doxycycline was started on day 6 at 50 mg/kg per day; corneal lesions that resulted from the injections were compared at days 6 and 15. Main Outcome Measures The Student t -test was used to evaluate the data for the CNV and DIVAA models and histologic preparations were used to evaluate pterygia lesions. Results There was significantly less NV and lesion volume with doxycycline taken in drinking water versus plain water. With doxycycline treatment, the laser-induced CNV showed a maximal 66% decrease in choroidal blood vessel volume ( P ≤0.008) and the DIVAA showed a 30% reduction of blood vessel growth and migration ( P Conclusions Doxycycline significantly inhibited angiogenesis in 3 murine models. The most dramatic effect was found in the CNV model followed by the pterygia epithelial cell DIVAA model. The anterior segment pterygium model also showed regression histologically. This suggests that doxycycline may be successful as an adjunctive treatment for CNV and pterygia in humans; clinical trials would be necessary to determine if there is a benefit. Financial Disclosure(s) The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Background: Human cripto-1 (CR-1) promotes cell transformation and increases migration and invasion of various mouse and human epithelial cell lines. We investigated whether CR-1 also stimulates angiogenesis. Methods: We used human umbilical vein endothelial cells (HUVECs) to measure in vitro migration with fibronectin-coated Boyden chambers, invasion with Matrigel-coated Boyden chambers, proliferation with a tetrazolium salt, and differentiation with an in vitro Matrigel assay. We investigated new blood vessel formation in vivo by use of Matrigel-filled silicone cylinders implanted under the skin of nude mice and by use of a breast cancer xenograft model with CR-1-transfected or control Neo-transfected MCF-7 human breast cancer cells. We also used a blocking anti-CR-1 monoclonal antibody to investigate the role of CR-1 in angiogenesis in vivo and in vitro. All statistical tests were two-sided. Results: CR-1 stimulated HUVEC proliferation, migration, and invasion and induced HUVEC differentiation into vascular-like structures on Matrigel. In vivo, recombinant CR-1 protein induced microvessel formation in Matrigel-filled silicone cylinders, and microvessel formation was statistically significantly inhibited with a blocking anti-CR-1 monoclonal antibody (CR-1 and antibody 127% of microvessel formation compared with that in untreated control cylinders and CR-1 alone 259%; difference 132%, 95% confidence interval [CI] 123% to 140%; P

Tissue inhibitor of metalloproteinase 1 (TIMP-1) is a stromal factor with multiple functions. Overexpression of TIMP-1 correlates with aggressive clinical behavior of a spectrum of tumors. Here, for the first time, we address the role of TIMP-1 in the pathogenesis of B-cell lymphomas. An Epstein-Barr virus (EBV)-negative Burkitt lymphoma cell line with ectopic TIMP-1 expression (TIMP-1JD38) was used to identify genes induced/repressed by TIMP-1. Differentially expressed genes were analyzed by cDNA microarray, and they were validated by immunohistochemistry, flow cytometry, and Western blotting. Analysis revealed changes of genes coding for B-cell growth/differentiation, transcription, and cell cycle regulators. TIMP-1 repressed expression of germinal center (GC) markers CD10, Bcl-6, PAX-5 and up-regulated plasma cell-associated antigens CD138, MUM-1/IRF-4, XBP-1, and CD44, suggesting a plasma cell differentiation. This is accompanied by activation of signal transducer and activator of transcription 3 (STAT-3) and switch to cyclin D2 expression. However, TIMP-1JD38 cells expressed an inactive form of XBP-1, lacking antibody production/secretion. This incomplete plasmacytic differentiation occurs without altering cell proliferation, and despite c-Myc deregulation, indicating an arrested plasmacytic/plasmablastic stage of differentiation. Further validation in human lymphoma cell lines and in primary B-cell tumors demonstrated a predominant TIMP-1 expression in tumors with plasmacytic/plasmablastic phenotypes, including multiple myelomas. These findings strongly support TIMP-1 as an important factor in the pathogenesis of plasmacytic/plasmablastic tumors. (Blood. 2005;105:1660-1668)

Tissue inhibitors of metalloproteinases (TIMPs) suppress matrix metalloproteinase (MMP) activity critical for extracellular matrix turnover associated with both physiologic and pathologic tissue remodeling. We demonstrate here that TIMP-2 abrogates angiogenic factor-induced endothelial cell proliferation in vitro and angiogenesis in vivo independent of MMP inhibition. These effects require alpha 3 beta 1 integrin-mediated binding of TIMP-2 to endothelial cells. Further, TIMP-2 induces a decrease in total protein tyrosine phosphatase (PTP) activity associated with beta1 integrin subunits as well as dissociation of the phosphatase SHP-1 from beta1. TIMP-2 treatment also results in a concomitant increase in PTP activity associated with tyrosine kinase receptors FGFR-1 and KDR. Our findings establish an unexpected, MMP-independent mechanism for TIMP-2 inhibition of endothelial cell proliferation in vitro and reveal an important component of the antiangiogenic effect of TIMP2 in vivo.

Tissue inhibitors of metalloproteinases (TIMPs) have been shown to be multifunctional factors. Contrasting with their enzyme-inhibitory activity, TIMPs also promote cell growth. Previously, we have reported an enhanced expression of TIMP-1 by normal reactive B cells and high-grade lymphomas. In the present study, a series of Burkitt’s lymphoma (BL) cell lines were analyzed for their expression of TIMP-1. TIMP-1 expression correlates with upregulation of activation and survival markers. TIMP-1–negative cells express the phenotype associated with group I BL lines and Epstein-Barr virus (EBV)-negative, nonendemic BLs (CD10+, CD38+, sIg+, and CD77+). However, TIMP-1+ BL lines showed group II/III BL phenotype, downregulation of the above markers, and upregulation and secretion of the activation marker CD23. Also, TIMP-1+ cells have high levels of CD40 expression. To determine whether TIMP-1 is directly involved in the BL phenotype, an EBV-negative BL line JD38 was infected with timp-1–expressing retrovirus and analyzed. In the absence of EBV, upregulation of TIMP-1 is sufficient to induce the same phenotype seen in TIMP-1+, EBV+ BL lines (CD10−, CD38−, sIg−, CD77−, CD23+, CD40 bright). This study not only suggests a role for TIMP-1 in BLs, but also supports its value as a prognostic factor.This is a US government work. There are no restrictions on its use.

Among the mechanisms of resistance to cancer treatment is the recruitment by tumors of inflammatory myeloid (CD11b+, Gr-1+) suppressor cells, promoting angiogenesis and tumor progression. Here, we report the effects of tissue inhibitor of metalloproteases(TIMP)-2 on the recruitment of CD11b+, Gr-1+ cells and subsequent suppression of tumor angiogenesis. Previously, we showed that xenografts of A549 cells with up-regulated TIMP-2 demonstrated significant reduction in the number of CD11b+, Gr-1+ cells, expression of VEGF-R2, and αvβ3 as well as reduced angiogenesis. Here, the effect of TIMP-2 on the growth of Luciferase-tagged-A549 cells was tested in vivo using the direct in vivo angiogenesis (DIVA) assay implanted subcutaneously containing 400 nM TIMP-2 or PBS. TIMP-2 decreased A549-cell proliferation in vivo as determined by quantitating bioluminescence emission. Immuno-histochemistry analysis of the tissue in TIMP-2 treated DIVAs demonstrated a drastic reduction in inflammation, fewer CD11b+, Gr-1+ cells were recruited into the TIMP-2 DIVA compared with untreated DIVA controls, as well as significant lower number of angiogenic vessels and invading endothelial cells were seen. Moreover, bone marrow from mice carrying DIVA with TIMP-2-treated A549 cells demonstrated a relative decrease in cell progenitors as compared with PBS treated tumor cells, suggesting that TIMP-2 blocked the release of tumor factors affecting the mobilization of bone marrow progenitors. These findings support TIMP-2 as anti-angiogenesis and anti-inflammatory factor. By targeting tumor-myeloid suppressors cells, TIMP-2 may have a therapeutic utility in the resistance of tumors to angiogenesis inhibitors. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1376. doi:1538-7445.AM2012-1376

Cellular pathways for induction of programmed cell death (PCD) have been identified, but little is known about specific extracellular matrix processes that may affect apoptosis along those pathways. In this study, a series of Burkitt's lymphoma (BL) cell lines were assayed for their expression of tissue inhibitor of metalloproteinases (TIMP)-1. Results indicate that TIMP-1-positive BL lines show resistance to cold-shock-induced apoptosis. Furthermore, recombinant TIMP-1, but not TIMP-2 or a synthetic metalloproteinase inhibitor (BB-94), confers resistance to apoptosis induced by both CD95-dependent and -independent (cold shock, serum deprivation, and gamma-radiation) pathways in TIMP-1-negative BL lines. TIMP-1 suppression of PCD is not due to metalloproteinase inhibition, as reduction and alkylation of the TIMP-1 did not abolish this activity. Retroviral induction of TIMP-1 not only resulted in cell survival but also in continued DNA synthesis for up to 5 d in the absence of serum, while controls underwent apoptosis. This resistance to apoptosis is reversed by anti-TIMP-1 antibodies, demonstrating that secreted TIMP-1 is active in blocking apoptosis. Furthermore, TIMP-1 upregulation induced expression of Bcl-XL but not Bcl-2 as well as decreased NF-kappaB activity as compared with controls. These results demonstrate that TIMP-1 suppresses apoptosis in B cells and suggests a novel activity for TIMP-1 in tissue homeostasis.