RESUMEN
The clinical use of first-generation phosphoinositide 3-kinase (PI3K)δ inhibitors in B-cell malignancies is hampered by hepatotoxicity, requiring dose reduction, treatment interruption, and/or discontinuation of therapy. In addition, potential molecular mechanisms by which resistance to this class of drugs occurs have not been investigated. Parsaclisib (INCB050465) is a potent and selective next-generation PI3Kδ inhibitor that differs in structure from first-generation PI3Kδ inhibitors and has shown encouraging anti-B-cell tumor activity and reduced hepatotoxicity in phase 1/2 clinical studies. Here, we present preclinical data demonstrating parsaclisib as a potent inhibitor of PI3Kδ with over 1000-fold selectivity against other class 1 PI3K isozymes. Parsaclisib directly blocks PI3K signaling-mediated cell proliferation in B-cell lines in vitro and in vivo and indirectly controls tumor growth by lessening immunosuppression through regulatory T-cell inhibition in a syngeneic lymphoma model. Diffuse large B-cell lymphoma cell lines overexpressing MYC were insensitive to proliferation blockade via PI3Kδ signaling inhibition by parsaclisib, but their proliferative activities were reduced by suppression of MYC gene transcription. Molecular structure analysis of the first- and next-generation PI3Kδ inhibitors combined with clinical observation suggests that hepatotoxicity seen with the first-generation inhibitors could result from a structure-related off-target effect. Parsaclisib is currently being evaluated in multiple phase 2 clinical trials as a therapy against various hematologic malignancies of B-cell origin (NCT03126019, NCT02998476, NCT03235544, NCT03144674, and NCT02018861). SIGNIFICANCE STATEMENT: The preclinical properties described here provide the mechanism of action and support clinical investigations of parsaclisib as a therapy for B-cell malignancies. MYC overexpression was identified as a resistance mechanism to parsaclisib in DLBCL cells, which may be useful in guiding further translational studies for the selection of patients with DLBCL who might benefit from PI3Kδ inhibitor treatment in future trials. Hepatotoxicity associated with first-generation PI3Kδ inhibitors may be an off-target effect of that class of compounds.
Asunto(s)
Hígado/efectos de los fármacos , Linfoma/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3/efectos adversos , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Pirazoles/efectos adversos , Pirazoles/farmacología , Pirimidinas/efectos adversos , Pirimidinas/farmacología , Pirrolidinas/efectos adversos , Pirrolidinas/farmacología , Animales , Antineoplásicos/efectos adversos , Antineoplásicos/farmacología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Femenino , Humanos , Factores Inmunológicos/efectos adversos , Factores Inmunológicos/farmacología , Ratones , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Phosphatidylinositol 3-kinase delta (PI3Kδ) is a critical signaling molecule in B cells and is considered a target for development of therapies against various B cell malignancies. INCB040093 is a novel PI3Kδ small-molecule inhibitor and has demonstrated promising efficacy in patients with Hodgkin's lymphoma in clinical studies. In this study, we disclose the chemical structure and the preclinical activity of the compound. In biochemical assays, INCB040093 potently inhibits the PI3Kδ kinase, with 74- to >900-fold selectivity against other PI3K family members. In vitro and ex vivo studies using primary B cells, cell lines from B cell malignancies, and human whole blood show that INCB040093 inhibits PI3Kδ-mediated functions, including cell signaling and proliferation. INCB040093 has no significant effect on the growth of nonlymphoid cell lines and was less potent in assays that measure human T and natural killer cell proliferation and neutrophil and monocyte functions, suggesting that the impact of INCB040093 on the human immune system will likely be restricted to B cells. INCB040093 inhibits the production of macrophage-inflammatory protein-1ß (MIP-1beta) and tumor necrosis factor-ß (TNF-beta) from a B cell line, suggesting a potential effect on the tumor microenvironment. In vivo, INCB040093 demonstrates single-agent activity in inhibiting tumor growth and potentiates the antitumor growth effect of the clinically relevant chemotherapeutic agent, bendamustine, in the Pfeiffer cell xenograft model of non-Hodgkin's lymphoma. INCB040093 has a favorable exposure profile in rats and an acceptable safety margin in rats and dogs. Taken together, data presented in this report support the potential utility of orally administered INCB040093 in the treatment of B cell malignancies.
Asunto(s)
Antineoplásicos/farmacología , Linfoma no Hodgkin/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/farmacología , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/metabolismo , Línea Celular , Proliferación Celular/efectos de los fármacos , Quimiocina CCL4/metabolismo , Perros , Femenino , Humanos , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/metabolismo , Linfoma no Hodgkin/metabolismo , Masculino , Ratones , Ratones SCID , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Neoplasias/metabolismo , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Ratas , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismoRESUMEN
We describe here the existence of a heregulin-HER3 autocrine loop, and the contribution of heregulin-dependent, HER2-mediated HER3 activation to gefitinib insensitivity in non-small cell lung cancer (NSCLC). ADAM17 protein, a major ErbB ligand sheddase, is upregulated in NSCLC and is required not only for heregulin-dependent HER3 signaling, but also for EGFR ligand-dependent signaling in NSCLC cell lines. A selective ADAM inhibitor, INCB3619, prevents the processing and activation of multiple ErbB ligands, including heregulin. In addition, INCB3619 inhibits gefitinib-resistant HER3 signaling and enhances gefitinib inhibition of EGFR signaling in NSCLC. These results show that ADAM inhibition affects multiple ErbB pathways in NSCLC and thus offers an excellent opportunity for pharmacological intervention, either alone or in combination with other drugs.
Asunto(s)
Proteínas ADAM/antagonistas & inhibidores , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/metabolismo , Piperidinas/farmacología , Receptor ErbB-3/metabolismo , Transducción de Señal/efectos de los fármacos , Compuestos de Espiro/farmacología , Proteínas ADAM/genética , Proteínas ADAM/metabolismo , Proteína ADAM17 , Animales , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Línea Celular Tumoral , Receptores ErbB/genética , Femenino , Gefitinib , Expresión Génica/genética , Humanos , Ligandos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Modelos Biológicos , Paclitaxel/farmacología , Piperidinas/uso terapéutico , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/farmacología , Compuestos de Espiro/uso terapéutico , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Indoleamine 2,3-dioxygenase-1 (IDO1; IDO) mediates oxidative cleavage of tryptophan, an amino acid essential for cell proliferation and survival. IDO1 inhibition is proposed to have therapeutic potential in immunodeficiency-associated abnormalities, including cancer. Here, we describe INCB024360, a novel IDO1 inhibitor, and investigate its roles in regulating various immune cells and therapeutic potential as an anticancer agent. In cellular assays, INCB024360 selectively inhibits human IDO1 with IC(50) values of approximately 10nM, demonstrating little activity against other related enzymes such as IDO2 or tryptophan 2,3-dioxygenase (TDO). In coculture systems of human allogeneic lymphocytes with dendritic cells (DCs) or tumor cells, INCB024360 inhibition of IDO1 promotes T and natural killer (NK)-cell growth, increases IFN-gamma production, and reduces conversion to regulatory T (T(reg))-like cells. IDO1 induction triggers DC apoptosis, whereas INCB024360 reverses this and increases the number of CD86(high) DCs, potentially representing a novel mechanism by which IDO1 inhibition activates T cells. Furthermore, IDO1 regulation differs in DCs versus tumor cells. Consistent with its effects in vitro, administration of INCB024360 to tumor-bearing mice significantly inhibits tumor growth in a lymphocyte-dependent manner. Analysis of plasma kynurenine/tryptophan levels in patients with cancer affirms that the IDO pathway is activated in multiple tumor types. Collectively, the data suggest that selective inhibition of IDO1 may represent an attractive cancer therapeutic strategy via up-regulation of cellular immunity.
Asunto(s)
Células Dendríticas/inmunología , Inhibidores Enzimáticos/farmacología , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Indolamina-Pirrol 2,3,-Dioxigenasa/inmunología , Neoplasias/inmunología , Linfocitos T/inmunología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/inmunología , Antígeno B7-2/inmunología , Antígeno B7-2/metabolismo , Técnicas de Cocultivo , Células Dendríticas/enzimología , Relación Dosis-Respuesta a Droga , Células HeLa , Humanos , Inmunidad Celular/efectos de los fármacos , Inmunidad Celular/inmunología , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Linfocitos T/enzimología , Triptófano Oxigenasa/inmunología , Triptófano Oxigenasa/metabolismoRESUMEN
We describe an isostere-driven approach to improve upon a previously-described series of capped dipeptide antagonists of CC Chemokine Receptor 2 (CCR2). Modification of the substitution around the isostere was combined with additional changes in a distal aromatic substituent to provide single-digit nanomolar antagonists of CCR2. These studies led to the identification of 18, a compound that was suitable for studies in murine models of CCR2 activity.
Asunto(s)
Amino Alcoholes/química , Receptores CCR2/antagonistas & inhibidores , Amino Alcoholes/farmacología , Animales , Disponibilidad Biológica , RatonesRESUMEN
We describe the design, synthesis, and evaluation of benzimidazoles as benzamide replacements within a series of trisubstituted cyclohexane CCR2 antagonists. 7-Trifluoromethylbenzimidazoles displayed potent binding and functional antagonism of CCR2 while being selective over CCR3. These benzimidazoles were also incorporated into lactam-containing antagonists, thus completely eliminating the customary bis-amide.
Asunto(s)
Bencimidazoles/farmacología , Ciclohexanos/química , Receptores CCR2/antagonistas & inhibidores , Bencimidazoles/síntesis química , Bencimidazoles/química , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Humanos , Microsomas/efectos de los fármacos , Estructura Molecular , Relación Estructura-ActividadRESUMEN
Blocking the activity of the programmed cell death protein 1 (PD-1) inhibitory receptor with therapeutic antibodies against either the ligand (PD-L1) or PD-1 itself has proven to be an effective treatment modality for multiple cancers. Contrasting with antibodies, small molecules could demonstrate increased tissue penetration, distinct pharmacology, and potentially enhanced antitumor activity. Here, we describe the identification and characterization of INCB086550, a novel, oral, small-molecule PD-L1 inhibitor. In vitro, INCB086550 selectively and potently blocked the PD-L1/PD-1 interaction, induced PD-L1 dimerization and internalization, and induced stimulation-dependent cytokine production in primary human immune cells. In vivo, INCB086550 reduced tumor growth in CD34+ humanized mice and induced T-cell activation gene signatures, consistent with PD-L1/PD-1 pathway blockade. Preliminary data from an ongoing phase I study confirmed PD-L1/PD-1 blockade in peripheral blood cells, with increased immune activation and tumor growth control. These data support continued clinical evaluation of INCB086550 as an alternative to antibody-based therapies. SIGNIFICANCE: We have identified a potent small-molecule inhibitor of PD-L1, INCB086550, which has biological properties similar to PD-L1/PD-1 monoclonal antibodies and may represent an alternative to antibody therapy. Preliminary clinical data in patients demonstrated increased immune activation and tumor growth control, which support continued clinical evaluation of this approach. See related commentary by Capparelli and Aplin, p. 1413. This article is highlighted in the In This Issue feature, p. 1397.
Asunto(s)
Antígeno B7-H1 , Neoplasias , Animales , Humanos , Inhibidores de Puntos de Control Inmunológico , Activación de Linfocitos , Ratones , Neoplasias/tratamiento farmacológico , Receptor de Muerte Celular Programada 1RESUMEN
We describe the design, synthesis, and evaluation, of gamma-lactams as glycinamide replacements within a series of di- and trisubstituted cyclohexane CCR2 antagonists. The lactam-containing trisubstituted cyclohexanes proved to be more potent than the disubstituted analogs, as trisubstituted analog, lactam 13, displayed excellent activity (CCR2 binding IC(50)=1.0 nM and chemotaxis IC(50) = 0.5 nM) and improved metabolic stability over its parent glycinamide.
Asunto(s)
Ciclohexanos/farmacología , Glicina/análogos & derivados , Lactamas/química , Receptores CCR2/antagonistas & inhibidores , Animales , Quimiotaxis/efectos de los fármacos , Ciclohexanos/química , Glicina/química , RatonesRESUMEN
TYRO3, AXL, and MERTK constitute the TAM family of receptor tyrosine kinases, which play important roles in tumor growth, survival, cell adhesion, as well as innate immunity, phagocytosis, and immune-suppressive activity. Therefore, targeting both AXL and MERTK kinases may directly impact tumor growth and relieve immunosuppression. We describe here the discovery of INCB081776, a potent and selective dual inhibitor of AXL and MERTK that is currently in phase 1 clinical trials. In cellular assays, INCB081776 effectively blocked autophosphorylation of AXL or MERTK with low nanomolar half maximal inhibitory concentration values in tumor cells and Ba/F3 cells transfected with constitutively active AXL or MERTK. INCB081776 inhibited activation of MERTK in primary human macrophages and partially reversed M2 macrophage-mediated suppression of T-cell proliferation, which was associated with increased interferon-γ production. In vivo, the antitumor activity of INCB081776 was enhanced in combination with checkpoint blockade in syngeneic models, and resulted in increased proliferation of intratumoral CD4+ and CD8+ T cells. Finally, antitumor activity of INCB081776 was observed in a subset of sarcoma patient-derived xenograft models, which was linked with inhibition of phospho-AKT. These data support the potential therapeutic utility of INCB081776 as an immunotherapeutic agent capable of both enhancing tumor immune surveillance and blocking tumor cell survival mechanisms.
RESUMEN
A series of trisubstituted cyclohexanes was designed, synthesized and evaluated as CC chemokine receptor 2 (CCR2) antagonists. This led to the identification of two distinct substitution patterns about the cyclohexane ring as potent and selective CCR2 antagonists. Compound 36 exhibited excellent binding (CCR2 IC(50)=2.4 nM) and functional antagonism (calcium flux IC(50)=2.0 nM and chemotaxis IC(50)=5.1 nM).
Asunto(s)
Química Farmacéutica/métodos , Receptores CCR2/antagonistas & inhibidores , Receptores CCR2/química , Sitios de Unión , Calcio/química , Quimiocina CCL2/química , Quimiotaxis , Ciclohexanos/química , Diseño de Fármacos , Humanos , Concentración 50 Inhibidora , Modelos Químicos , Estructura Molecular , Unión Proteica , Relación Estructura-ActividadRESUMEN
Potent sulfone-containing di- and trisubstituted cyclohexanes were synthesized and evaluated as CC chemokine receptor 2 (CCR2) antagonists. This led to the trisubstituted derivative 54, which exhibited excellent binding (CCR2 IC(50)=1.3nM) and functional antagonism (calcium flux IC(50)=0.5nM and chemotaxis IC(50)=0.2nM). The superiority of the trisubstituted scaffold was rationalized to be the result of a conformational rigidification, which provided insight into the bioactive conformation of this chemotype.
Asunto(s)
Ciclohexanos/síntesis química , Receptores CCR2/antagonistas & inhibidores , Sulfonas/química , Ciclohexanos/química , Ciclohexanos/farmacología , Conformación Molecular , Receptores CCR2/metabolismo , Sulfonas/síntesis químicaRESUMEN
We describe the design, synthesis, and evaluation of novel disubstituted cyclohexanes as potent CCR2 antagonists. Exploratory SAR studies led to the cis-disubstituted derivative 22, which displayed excellent binding affinity for CCR2 (binding IC50 = 5.1 nM) and potent functional antagonism (calcium flux IC50 = 18 nM and chemotaxis IC 50 = 1 nM). Site-directed mutagenesis studies with 22 suggest the compound is binding near the key receptor residue Glu291, however, 22 is not reliant on Glu291 for its binding affinity.
Asunto(s)
Ciclohexanos/síntesis química , Receptores CCR2/antagonistas & inhibidores , Unión Competitiva , Calcio/metabolismo , Quimiocina CCL2/metabolismo , Quimiotaxis de Leucocito/efectos de los fármacos , Ciclohexanos/química , Ciclohexanos/farmacología , Humanos , Técnicas In Vitro , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Ensayo de Unión Radioligante , Receptores CCR2/genética , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
A series of cis-3,4-disubstituted piperidines was synthesized and evaluated as CC chemokine receptor 2 (CCR2) antagonists. Compound 24 emerged with an attractive profile, possessing excellent binding (CCR2 IC(50)=3.4 nM) and functional antagonism (calcium flux IC(50)=2.0 nM and chemotaxis IC(50)=5.4 nM). Studies to explore the binding of these piperidine analogs utilized a key CCR2 receptor mutant (E291A) with compound 14 and revealed a significant reliance on Glu291 for binding.
Asunto(s)
Ácido Glutámico/metabolismo , Piperidinas/síntesis química , Piperidinas/farmacología , Receptores CCR2/antagonistas & inhibidores , Técnicas Químicas Combinatorias , Ácido Glutámico/química , Concentración 50 Inhibidora , Estructura Molecular , Piperidinas/química , Receptores CCR2/genética , Estereoisomerismo , Relación Estructura-ActividadRESUMEN
A series of beta-sulfonamide piperidine hydroxamates were prepared and shown to be potent inhibitors of the human epidermal growth factor receptor-2 (HER-2) sheddase with excellent selectivity against MMP-1, -2, -3, and -9. This was achieved by exploiting subtle differences within the otherwise highly conserved S(1)(') binding pocket of the active sites within the metalloprotease family. In addition, it was discovered that the introduction of polarity to the P(1) and P(1)(') groups reduced the projected human clearance.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Metaloproteinasas de la Matriz/metabolismo , Piperidinas/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Sitios de Unión , Humanos , Metaloproteinasas de la Matriz/química , Piperidinas/química , Piperidinas/metabolismo , Receptor ErbB-2/químicaRESUMEN
In an effort to obtain a MMP selective and potent inhibitor of HER-2 sheddase (ADAM-10), the P1' group of a novel class of (6S,7S)-7-[(hydroxyamino)carbonyl]-6-carboxamide-5-azaspiro[2.5]octane-5-carboxylates was attenuated and the structure-activity relationships (SAR) will be discussed. In addition, it was discovered that unconventional perturbation of the P2' moiety could confer MMP selectivity, which was hypothesized to be a manifestation of the P2' group effecting global conformational changes.
Asunto(s)
Proteínas ADAM/antagonistas & inhibidores , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Ácidos Hidroxámicos/química , Proteínas de la Membrana/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Receptor ErbB-2/antagonistas & inhibidores , Proteínas ADAM/metabolismo , Proteína ADAM10 , Amidas/síntesis química , Amidas/química , Amidas/farmacología , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Compuestos Aza/síntesis química , Compuestos Aza/química , Compuestos Aza/farmacología , Diseño de Fármacos , Ácidos Hidroxámicos/síntesis química , Ácidos Hidroxámicos/farmacología , Proteínas de la Membrana/metabolismo , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Estructura Terciaria de Proteína , Receptor ErbB-2/metabolismo , Compuestos de Espiro/síntesis química , Compuestos de Espiro/química , Compuestos de Espiro/farmacología , Relación Estructura-Actividad , Especificidad por SustratoRESUMEN
The HER-2 receptor tyrosine kinase is an important regulator of cell proliferation and survival, and it is a clinically validated target of therapeutic intervention for HER-2 positive breast cancer patients. Its extracellular domain (ECD) is frequently cleaved by protease(s) in HER-2 overexpressing breast cancer patients, rendering the remaining membrane-bound portion (p95) a constitutively activated kinase. The presence of both serum ECD and cellular p95 protein has been linked to poor clinical outcome as well as reduced effectiveness of some therapeutic treatments. We have identified a series of potent, selective small molecule inhibitors of ADAM proteases, exemplified here by INCB003619, and demonstrate that these inhibitors effectively block HER-2 cleavage in HER-2 overexpressing human breast cancer cell lines. Intriguingly, when used in combination, INCB003619 dramatically enhances the antiproliferative activity of suboptimal doses of the anti-HER-2 antibody, trastuzumab, in HER-2 overexpressing/shedding breast cancer cell lines, accompanied by reduced ERK and AKT phosphorylation. Furthermore, INCB003619, in combination with trastuzumab, augments the pro-apoptotic and antiproliferative effects of the chemotherapeutic agent paclitaxel. Consistent with these in vitro data, INCB003619 reduces serum ECD levels and enhances the antitumor effect of trastuzumab in a xenograft tumor model derived from the HER-2 overexpressing BT-474 breast cancer cell line. Collectively, these findings suggest that blocking HER-2 cleavage with selective ADAM inhibitors may represent a novel therapeutic approach for treating HER-2 overexpressing breast cancer patients.
Asunto(s)
Proteínas ADAM/antagonistas & inhibidores , Anticuerpos Monoclonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Receptor ErbB-2/antagonistas & inhibidores , Animales , Anticuerpos Monoclonales Humanizados , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Desnudos , Trasplante Heterólogo , TrastuzumabRESUMEN
Overexpression and activating mutations of ErbB family members have been implicated in the development and progression of a variety of tumor types. Cleavage of the HER2 receptor by an as yet unidentified ectodomain sheddase has been shown to liberate the HER2 extracellular domain (ECD) leaving a fragment with constitutive kinase activity that can provide ligand-independent growth and survival signals to the cell. This process is clinically relevant since HER2 ECD serum levels in metastatic breast cancer patients are associated with a poorer prognosis. Thus, inhibition of the HER2 sheddase may provide a novel therapeutic approach for breast cancer. We describe the use of transcriptional profiling, pharmacological and in vitro approaches to identify the major source of HER2 sheddase activity. Real-time PCR was used to identify those ADAM family members which were expressed in HER2 shedding cell lines. siRNAs that selectively inhibited ADAM10 expression reduced HER2 shedding. In addition, we profiled over 1000 small molecules for in vitro inhibition of a panel of ADAM and MMP proteins; a positive correlation was observed only between ADAM10 inhibition and reduction of HER2 ECD shedding in a cell based assay. Finally, in vitro studies demonstrate that in combination with low doses of Herceptin, selective ADAM10 inhibitors decrease proliferation in HER2 overexpressing cell lines while inhibitors, that do not inhibit ADAM10, have no impact. These results are consistent with ADAM10 being a major determinant of HER2 shedding, the inhibition of which, may provide a novel therapeutic approach for treating a variety of cancers with active HER2 signaling.
Asunto(s)
Proteínas ADAM/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Neoplasias de la Mama/genética , Proteínas de la Membrana/metabolismo , Receptor ErbB-2/metabolismo , Proteína ADAM10 , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales Humanizados , Antineoplásicos/farmacología , Secuencia de Bases , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Reacción en Cadena de la Polimerasa , ARN Interferente Pequeño/genética , TrastuzumabRESUMEN
PURPOSE: The c-MET receptor tyrosine kinase plays important roles in the formation, progression, and dissemination of human cancer and presents an attractive therapeutic target. This study describes the preclinical characterization of INCB28060, a novel inhibitor of c-MET kinase. EXPERIMENTAL DESIGN: Studies were conducted using a series of in vitro and in vivo biochemical and biological experiments. RESULTS: INCB28060 exhibits picomolar enzymatic potency and is highly specific for c-MET with more than 10,000-fold selectivity over a large panel of human kinases. This inhibitor potently blocks c-MET phosphorylation and activation of its key downstream effectors in c-MET-dependent tumor cell lines. As a result, INCB28060 potently inhibits c-MET-dependent tumor cell proliferation and migration and effectively induces apoptosis in vitro. Oral dosing of INCB28060 results in time- and dose-dependent inhibition of c-MET phosphorylation and tumor growth in c-MET-driven mouse tumor models, and the inhibitor is well tolerated at doses that achieve complete tumor inhibition. In a further exploration of potential interactions between c-MET and other signaling pathways, we found that activated c-MET positively regulates the activity of epidermal growth factor receptors (EGFR) and HER-3, as well as expression of their ligands. These effects are reversed with INCB28060 treatment. Finally, we confirmed that circulating hepatocyte growth factor levels are significantly elevated in patients with various cancers. CONCLUSIONS: Activated c-MET has pleiotropic effects on multiple cancer-promoting signaling pathways and may play a critical role in driving tumor cell growth and survival. INCB28060 is a potent and selective c-MET kinase inhibitor that may have therapeutic potential in cancer treatment.
Asunto(s)
Antineoplásicos/uso terapéutico , Benzamidas/uso terapéutico , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Receptores ErbB/metabolismo , Neoplasias Experimentales/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Receptor Cross-Talk/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Animales , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Activación Enzimática , Femenino , Glioblastoma/tratamiento farmacológico , Humanos , Imidazoles , Ratones , Ratones Desnudos , Fosforilación , Inhibidores de Proteínas Quinasas/uso terapéutico , Receptor ErbB-3/metabolismo , Triazinas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Malignant tumors arise, in part, because the immune system does not adequately recognize and destroy them. Expression of indoleamine-2,3-dioxygenase (IDO; IDO1), a rate-limiting enzyme in the catabolism of tryptophan into kynurenine, contributes to this immune evasion. Here we describe the effects of systemic IDO inhibition using orally active hydroxyamidine small molecule inhibitors. A single dose of INCB023843 or INCB024360 results in efficient and durable suppression of Ido1 activity in the plasma of treated mice and dogs, the former to levels seen in Ido1-deficient mice. Hydroxyamidines potently suppress tryptophan metabolism in vitro in CT26 colon carcinoma and PAN02 pancreatic carcinoma cells and in vivo in tumors and their draining lymph nodes. Repeated administration of these IDO1 inhibitors impedes tumor growth in a dose- and lymphocyte-dependent fashion and is well tolerated in efficacy and preclinical toxicology studies. Substantiating the fundamental role of tumor cell-derived IDO expression, hydroxyamidines control the growth of IDO-expressing tumors in Ido1-deficient mice. These activities can be attributed, at least partially, to the increased immunoreactivity of lymphocytes found in tumors and their draining lymph nodes and to the reduction in tumor-associated regulatory T cells. INCB024360, a potent IDO1 inhibitor with desirable pharmaceutical properties, is poised to start clinical trials in cancer patients.
Asunto(s)
Amidinas/farmacología , Inhibidores Enzimáticos/farmacología , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Neoplasias/metabolismo , Triptófano/metabolismo , Animales , Línea Celular Tumoral , Perros , Femenino , Humanos , Sistema Inmunológico , Inmunoterapia/métodos , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Quinurenina/farmacología , Ganglios Linfáticos/patología , Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Neoplasias/tratamiento farmacológico , Neoplasias/patologíaRESUMEN
A new series of CCR2 antagonists has been discovered that incorporates intramolecular hydrogen bonding as a strategy for rigidifying the scaffold. The structure-activity relationship was established through initial systematic modification of substitution pattern and chain length, followed by independent optimization of three different substituents (benzylamine, carboxamide, and benzamide). Several of the acyclic compounds display 10-30 nM binding affinity for CCR2. Moreover, these antagonists are able to block both MCP-1-induced Ca(2+) flux and monocyte chemotaxis, and are selective for binding to CCR2 over CCR1 and CCR3.