Matrix metalloproteinases (MMPs) are endopeptidases that play pivotal roles in promoting tumor disease progression, including tumor angiogenesis. In many solid tumors, MMP expression could be attributed to tumor stromal cells and is partially regulated by tumor-stroma interactions via tumor cell-associated extracellular matrix metalloproteinase inducer (EMMPRIN). The role of EMMPRIN during tumor angiogenesis and growth was explored by modulating EMMPRIN expression and activity using recombinant DNA engineering and neutralizing antibodies. In human breast cancer cells, changes in EMMPRIN expression influenced vascular endothelial growth factor (VEGF) production at both RNA and protein levels. In coculture of tumor cells and fibroblasts mimicking tumor-stroma interactions, VEGF expression was induced in an EMMPRIN- and MMP-dependent fashion, and was further enhanced by overexpressing EMMPRIN. Conversely, VEGF expression was inhibited by suppressing EMMPRIN expression in tumor cells, by neutralizing EMMPRIN activity, or by inhibiting MMPs. In vivo, EMMPRIN overexpression stimulated tumor angiogenesis and growth; both were significantly inhibited by antisense suppression of EMMPRIN. Expression of both human and mouse VEGF and MMP, derived from tumor and host cells, respectively, was regulated by EMMPRIN. These results suggest a novel tumor angiogenesis mechanism in which tumor-associated EMMPRIN functionally mediates tumor-stroma interactions and directly contributes to tumor angiogenesis and growth by stimulating VEGF and MMP expression.
Extracellular matrix metalloproteinase (MMP) inducer (EMMPRIN) is a cell surface glycoprotein overexpressed in many solid tumors. In addition to its ability to stimulate stromal MMP expression, tumor-associated EMMPRIN also induces vascular endothelial growth factor (VEGF) expression. To explore the underlying signaling pathways used by EMMPRIN, we studied the involvement of phosphoinositide 3-kinase (PI3K)-Akt, mitogen-activated protein kinase (MAPK), JUN, and p38 kinases in EMMPRIN-mediated VEGF regulation. Overexpression of EMMPRIN in MDA-MB-231 breast cancer cells stimulated the phosphorylation of only Akt and MAPKs but not that of JUN and p38 kinases. Conversely, inhibition of EMMPRIN expression resulted in suppressed Akt and MAPK phosphorylation. Furthermore, the PI3K-specific inhibitor LY294002 inhibited VEGF production by EMMPRIN-overexpressing cells in a dose-and time-dependent manner. On the other hand, the MAPK inhibitor U0126 did not affect VEGF production. In vivo, EMMPRIN-overexpressing tumors with elevated VEGF expression had a high level of phosphorylation of Akt and MAPK. Finally, when fibroblast cells were treated with recombinant EMMPRIN, Akt kinase but not MAPK was phosphorylated concomitant with an increase in VEGF production. Both the activation of Akt kinase and the induction of VEGF were specifically inhibited with a neutralizing antibody to EMMPRIN. Our results show that in both tumor and fibroblast cells EMMPRIN regulates VEGF production via the PI3K-Akt pathway but not via the MAPK, JUN, or p38 kinase pathways. (Mol Cancer Res 2006;4(6):371 -8)
CNTO 95 is a fully human monoclonal antibody that recognizes alphav integrins. Previous studies have shown that CNTO 95 exhibits both anti-tumor and anti-angiogenic activities (Trikha M et al., Int J Cancer 110:326-335, 2004). In this study we investigated the biological activities of CNTO 95 on breast tumor cells both in vitro and in vivo. In vitro treatment with CNTO 95 decreased the viability of breast tumor cells adhering to vitronectin. CNTO 95 inhibited tumor cell adhesion, migration, and invasion in vitro. CNTO 95 treatment also induced tyrosine dephosphorylation of focal adhesion kinase (FAK), and the docking protein paxillin that recruits both structural and signaling molecules to focal adhesions (Turner CE, Int J Biochem Cell Biol 30:955-959, 1998; O'Neil GM et al., Trends Cell Biol 10:111-119, 2000). These results suggest that CNTO 95 inhibits breast tumor cell growth, migration and invasion by interruption of alphav integrin mediated focal adhesions and cell motility signals. In vivo studies of CNTO 95 were conducted in an orthotopic breast tumor xenograft model. Treatment with CNTO 95 resulted in significant inhibition of both tumor growth and spontaneous metastasis of MDA-MB-231 cells to the lungs. CNTO 95 also inhibited lung metastasis in a separate experimental (tail vein injection) model of metastasis. The results presented here demonstrate the anti-tumor and anti-metastatic activities of CNTO 95 in breast cancer models and provide insight into the cellular and molecular mechanisms mediating its inhibitory effects on metastasis.
Small molecule inhibitors targeting mutant epidermal growth factor receptor (EGFR) are standard of care in non-small cell lung cancer (NSCLC), but acquired resistance invariably develops through mutations in EGFR or through activation of compensatory pathways such as cMet. Amivantamab (JNJ-61186372) is an anti-EGFR and anti-cMet bispecific low fucose antibody with enhanced Fc function designed to treat tumors driven by activated EGFR and/or cMet signaling. Potent in vivo anti-tumor efficacy is observed upon amivantamab treatment of human tumor xenograft models driven by mutant activated EGFR and this activity is associated with receptor downregulation. Despite these robust anti-tumor responses in vivo, limited antiproliferative effects and EGFR/cMet receptor downregulation by amivantamab were observed in vitro. Interestingly, in vitro addition of isolated human immune cells notably enhanced amivantamab-mediated EGFR and cMet downregulation leading to antibody dose-dependent cancer cell killing. Through a comprehensive assessment of the Fc-mediated effector functions, we demonstrate that monocytes and/or macrophages, through trogocytosis, are necessary and sufficient for Fc interaction-mediated EGFR/cMet downmodulation and are required for in vivo anti-tumor efficacy. Collectively, our findings represent a novel Fc-dependent macrophagemediated anti-tumor mechanism of amivantamab and highlight trogocytosis as an important mechanism of action to exploit in designing new antibody-based cancer therapies.
Thromboembolic complications are frequently associated with advanced cancer. Interestingly, one of the major initiators of blood coagulation, tissue factor (TF), is reported to be overexpressed in several tumor types and can be found on both tumor cells and tumor vasculature. Although the exact mechanisms have yet to be elucidated, TF expressed on tumor cells can trigger intracellular signaling events through various pathways that can lead to tumor angiogenesis, proliferation, and metastasis. There exists preclinical evidence that disruption of TF dependent signaling can effectively inhibit tumor cell migration, metastasis, and angiogenesis. Here, we report for the first time that an antibody to tissue factor can also prevent tumor growth in vivo. Prophylactic administration of CNTO 859, a humanized anti-human TF antibody, was shown to inhibit experimental lung metastasis of MDA-MB-231 human breast carcinoma cells by over 99% compared to a control antibody. Furthermore, therapeutic doses of CNTO 859 were shown to reduce tumor incidence and growth of orthotopically implanted MDA-MB-231 cells. ' 2006 Wiley-Liss, Inc.
The protein arginine methyltransferase 5 (PRMT5) methylates a variety of proteins involved in splicing, multiple signal transduction pathways, epigenetic control of gene expression, and mechanisms leading to protein expression required for cellular proliferation. Dysregulation of PRMT5 is associated with clinical features of several cancers including lymphomas, lung cancer, and breast cancer. Here, we describe the characterization of JNJ-64619178, a novel, selective, and potent PRMT5 inhibitor, currently in clinical trials for patients with advanced solid tumors, non-Hodgkin's lymphoma, and lower risk myelodysplastic syndrome.JNJ-64619178 demonstrated a prolonged inhibition of PRMT5 and potent anti-proliferative activity in subsets of cancer cell lines derived from various histologies, including lung, breast, pancreatic, and hematological malignancies. In primary acute myeloid leukemia samples, the presence of splicing factor mutations correlated with a higher ex vivo sensitivity to JNJ-64619178. Furthermore, the potent and unique mechanism of inhibition of JNJ-64619178, combined with highly optimized pharmacological properties, led to efficient tumor growth inhibition and regression in several xenograft models in vivo, with once-daily or intermittent oral dosing schedules. An increase in splicing burden was observed upon JNJ-64619178 treatment. Overall, these observations support the continued clinical evaluation of JNJ-64619178 in patients with aberrant PRMT5 activity driven tumors.
Purpose: Targeted delivery of cytotoxic agents to solid tumors through cell surface antigens can potentially reduce systemic toxicity and increase the efficacy of the targeted compounds. The purpose of this study was to show the feasibility of treating solid tumors by targeting a v integrins with antibody-maytansinoid conjugates and to test the relative in vivo activities of several linkermaytansinoid chemistries. Experimental Design: CNTO 364, CNTO 365, and CNTO 366 are targeted cytotoxic agents created by conjugating the CNTO 95 anti-a v integrin antibody with three distinct maytansinoidlinker structures.These structures were designed to have varying degrees of chemical substitution surrounding the disulfide bond linking the cytotoxic agent to the antibody. A model conjugate was shown to be specifically cytotoxic in vitro and highly active against established human tumor xenografts in immunocompromised rats. The in vivo antitumor activities of CNTO 364, CNTO 365, and CNTO 366 were compared in rat xenograft models. Results: CNTO 365, with a linker chemistry of expected intermediate stability, was shown to be substantially more active than the other two conjugates with lesser or greater substitution around the disulfide linkage. Conclusion: CNTO 95^maytansinoid immunoconjugates are potent antitumor agents against a v integrin^expressing human carcinomas. These studies show for the first time the feasibility of targeting a v integrins on solid tumors with tumor-activated prodrugs. The DM4 linker-maytansinoid configuration of CNTO 365 was substantially more active in the models tested here when compared with alternative configurations with greater or lesser chemical substitution surrounding the linker.The a v integrin subfamily consists of at least five members, including a v h 1 , a v h 3 , a v h 5 , a v h 6 , and a v h 8 (1). a v Integrins a v h 3 , a v h 5 , and a v h 6 have been implicated in angiogenesis and tumor progression (2 -5). Up-regulation of a v integrins has been observed in various types of human cancer, including melanoma (6), renal (7), ovarian (8), gastric (9), breast (10), and colorectal carcinoma (11). The frequent overexpression of a v integrins by tumors, their more limited expression by healthy tissues, and their importance in tumor growth and progression make them attractive targets for cancer therapies. CNTO 95, a fully human monoclonal antibody, inhibits a v integrins and has in vivo antitumor and antiangiogenic activity (12). It is one of several a v integrin inhibitors, including both monoclonal antibodies and small molecules, that have been tested both preclinically and clinically for the treatment of solid tumors (4).Immunoconjugates are bifunctional molecules that combine the specificity of monoclonal antibodies to tumor antigens with the potency of cytotoxic agents (13 -15). To take advantage of the a v integrin specificity of CNTO 95, we generated the antibody-drug conjugates CNTO 364, CNTO 365, and CNTO 366. These molecules are tumor-activated prodrugs in which derivativ...
PRMT5 is a type II methyltransferase that symmetrically di-methylates arginine residues on proteins involved in signal transduction and cellular transcription. For example, PRMT5 acts as the enzymatic machinery of the methylosome complex, crucial for spliceosome assembly and activity. Although not frequently mutated or amplified in tumors, an elevated PRMT5 protein level that leads to higher methylosome activity and promotes epithelial–mesenchymal transition, has recently been correlated with a poor survival of cancer patients. The PRMT5 inhibitor JNJ-64619178 has been selected as a clinical candidate based on its high selectivity and potency, paired with favorable oral pharmacokinetics and safety properties. JNJ-64619178 binds simultaneously to the SAM- and protein substrate- binding pockets of the PRMT5/MEP50 complex with a pseudo-irreversible mode-of-action. Chemical proteomics, methylomics and RNA-sequencing analyses of PRMT5 inhibitor treated cell line samples support the current biological understanding of PRMT5 as a regulator of alternative splicing events. JNJ-64619178 showed potent and broad inhibition of cellular growth, observed in several cell line panels that represent diverse cancer histologies. Ongoing investigations will explore the potential synthetic lethal correlation between PRMT5 inhibition and cancer driver pathways, including those addicted to altered splicing. Oral administration of JNJ-64619178 resulted in efficient inhibition of di-methylation of SMD1/3 proteins, components of the splicing machinery and direct substrates of the methylosome, in several human NSCLC and SCLC cancer mouse xenograft models. JNJ-64619178 demonstrated dose-dependent tumor growth inhibition and regression in several human NSCLC and SCLC cancer mouse xenograft models with sustained blockage of tumor re-growth after dosing cessation. In summary, JNJ-64619178 has a favorable pre-clinical profile supporting clinical testing in patients with lung cancer and other malignancies. Citation Format: Tongfei Wu, Hillary Millar, Dana Gaffney, Lijs Beke, Geert Mannens, Petra Vinken, Ivan Sommers, Jan-Willem Thuring, Weimei Sun, Christopher Moy, Vineet Pande, Junguo Zhou, Nahor Haddish-Berhane, Mark Salvati, Sylvie Laquerre, Matthew V. Lorenzi, Dirk Brehmer. JNJ-64619178, a selective and pseudo-irreversible PRMT5 inhibitor with potent in vitro and in vivo activity, demonstrated in several lung cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4859.
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