RESUMEN
We previously disclosed the identification of cereblon modulator 3 (CC-885), with potent antitumor activity mediated through the degradation of GSPT1. We describe herein the structure-activity relationships for analogs of 3 with exploration of the structurally related dioxoisoindoline class. The observed activity of protein degradation could in part be rationalized through docking into the previously disclosed 3-CRBN-GSPT1 cocrystal ternary complex. For SAR that could not be rationalized through the cocrystal complex, we sought to predict SAR through a QSAR model developed in house. Through these analyses, selective protein degradation could be achieved between the two proteins of interest, GSPT1 and Aiolos.
Asunto(s)
Factor de Transcripción Ikaros/metabolismo , Factores de Terminación de Péptidos/metabolismo , Proteolisis/efectos de los fármacos , Relación Estructura-Actividad Cuantitativa , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Antineoplásicos/química , Antineoplásicos/farmacología , Técnicas de Química Sintética , Evaluación Preclínica de Medicamentos/métodos , Humanos , Factor de Transcripción Ikaros/química , Factor de Transcripción Ikaros/genética , Simulación del Acoplamiento Molecular , Mieloma Múltiple , Péptido Hidrolasas/química , Péptido Hidrolasas/metabolismo , Factores de Terminación de Péptidos/química , Factores de Terminación de Péptidos/genética , Ftalimidas/química , Piperidonas/químicaRESUMEN
The drugs lenalidomide and pomalidomide bind to the protein cereblon, directing the CRL4-CRBN E3 ligase toward the transcription factors Ikaros and Aiolos to cause their ubiquitination and degradation. Here we describe CC-220 (compound 6), a cereblon modulator in clinical development for systemic lupus erythematosis and relapsed/refractory multiple myeloma. Compound 6 binds cereblon with a higher affinity than lenalidomide or pomalidomide. Consistent with this, the cellular degradation of Ikaros and Aiolos is more potent and the extent of substrate depletion is greater. The crystal structure of cereblon in complex with DDB1 and compound 6 reveals that the increase in potency correlates with increased contacts between compound 6 and cereblon away from the modeled binding site for Ikaros/Aiolos. These results describe a new cereblon modulator which achieves greater substrate degradation via tighter binding to the cereblon E3 ligase and provides an example of the effect of E3 ligase binding affinity with relevance to other drug discovery efforts in targeted protein degradation.
Asunto(s)
Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Factor de Transcripción Ikaros/metabolismo , Péptido Hidrolasas/química , Péptido Hidrolasas/metabolismo , Proteolisis/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales , Línea Celular Tumoral , Cristalografía por Rayos X , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Compuestos Heterocíclicos de 4 o más Anillos/química , Compuestos Heterocíclicos de 4 o más Anillos/metabolismo , Humanos , Lenalidomida/química , Lenalidomida/metabolismo , Morfolinas , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/metabolismo , Ftalimidas , Piperidonas , Unión Proteica , Ubiquitina-Proteína LigasasRESUMEN
Lenalidomide is a highly effective treatment for myelodysplastic syndrome (MDS) with deletion of chromosome 5q (del(5q)). Here, we demonstrate that lenalidomide induces the ubiquitination of casein kinase 1A1 (CK1α) by the E3 ubiquitin ligase CUL4-RBX1-DDB1-CRBN (known as CRL4(CRBN)), resulting in CK1α degradation. CK1α is encoded by a gene within the common deleted region for del(5q) MDS and haploinsufficient expression sensitizes cells to lenalidomide therapy, providing a mechanistic basis for the therapeutic window of lenalidomide in del(5q) MDS. We found that mouse cells are resistant to lenalidomide but that changing a single amino acid in mouse Crbn to the corresponding human residue enables lenalidomide-dependent degradation of CK1α. We further demonstrate that minor side chain modifications in thalidomide and a novel analogue, CC-122, can modulate the spectrum of substrates targeted by CRL4(CRBN). These findings have implications for the clinical activity of lenalidomide and related compounds, and demonstrate the therapeutic potential of novel modulators of E3 ubiquitin ligases.
Asunto(s)
Quinasa de la Caseína I/metabolismo , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/fisiopatología , Talidomida/análogos & derivados , Ubiquitinación/efectos de los fármacos , Secuencia de Aminoácidos , Animales , Quinasa de la Caseína I/genética , Línea Celular , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Factores Inmunológicos/farmacología , Células Jurkat , Células K562 , Lenalidomida , Ratones , Datos de Secuencia Molecular , Péptido Hidrolasas/química , Proteolisis/efectos de los fármacos , Alineación de Secuencia , Eliminación de Secuencia , Especificidad de la Especie , Talidomida/farmacología , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
Cereblon (CRBN), a substrate receptor of the Cullin 4 RING E3 ubiquitin ligase complex, is the target of the immunomodulatory drugs lenalidomide and pomalidomide. Recently, it was demonstrated that binding of these drugs to CRBN promotes the ubiquitination and subsequent degradation of 2 common substrates, transcription factors Aiolos and Ikaros. Here we report that CC-122, a new chemical entity termed pleiotropic pathway modifier, binds CRBN and promotes degradation of Aiolos and Ikaros in diffuse large B-cell lymphoma (DLBCL) and T cells in vitro, in vivo, and in patients, resulting in both cell autonomous as well as immunostimulatory effects. In DLBCL cell lines, CC-122-induced degradation or short hairpin RNA-mediated knockdown of Aiolos and Ikaros correlates with increased transcription of interferon (IFN)-stimulated genes independent of IFN-α, -ß, and -γ production and/or secretion and results in apoptosis in both activated B-cell (ABC) and germinal center B-cell DLBCL cell lines. Our results provide mechanistic insight into the cell-of-origin independent antilymphoma activity of CC-122, in contrast to the ABC subtype selective activity of lenalidomide.
Asunto(s)
Antineoplásicos/farmacología , Linfocitos B/efectos de los fármacos , Factor de Transcripción Ikaros/genética , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Péptido Hidrolasas/genética , Piperidonas/farmacología , Quinazolinonas/farmacología , Transducción de Señal/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales , Animales , Antineoplásicos/química , Linfocitos B/metabolismo , Linfocitos B/patología , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , Factor de Transcripción Ikaros/metabolismo , Factor 7 Regulador del Interferón/genética , Factor 7 Regulador del Interferón/metabolismo , Interferones/genética , Interferones/metabolismo , Lenalidomida , Lentivirus/genética , Lentivirus/metabolismo , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/metabolismo , Linfoma de Células B Grandes Difuso/patología , Ratones , Ratones SCID , Imitación Molecular , Péptido Hidrolasas/metabolismo , Piperidonas/química , Proteolisis/efectos de los fármacos , Quinazolinonas/química , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Transducción de Señal/genética , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Linfocitos T/patología , Talidomida/análogos & derivados , Talidomida/farmacología , Ubiquitina-Proteína Ligasas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
A series of analogs of the immunomodulary drugs lenalidomide (1) and pomalidomide (2), in which the amino group is replaced with various isosteres, was prepared and assayed for immunomodulatory activity and activity against cancer cell lines. The 4-methyl and 4-chloro analogs 4 and 15, respectively, displayed potent inhibition of tumor necrosis factor-α (TNF-α) in LPS-stimulated hPBMC, potent stimulation of IL-2 in a human T cell co-stimulation assay, and anti-proliferative activity against the Namalwa lymphoma cell line. Both of these analogs displayed oral bioavailability in rat.
Asunto(s)
Talidomida/análogos & derivados , Administración Oral , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Semivida , Humanos , Interleucina-2/metabolismo , Lenalidomida , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Ratas , Relación Estructura-Actividad , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Talidomida/química , Talidomida/farmacocinética , Talidomida/toxicidad , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
A series of 1,1-diarylalkene derivatives were prepared to optimize the properties of CC-5079 (1), a dual inhibitor of tubulin polymerization and phosphodiesterase 4 (PDE4). By using the 3-ethoxy-4-methoxyphenyl PDE4 pharmacophore as one of the aromatic rings, a significant improvement in PDE4 inhibition was achieved. Compound 28 was identified as a dual inhibitor with potent PDE4 (IC(50)=54 nM) and antitubulin activity (HCT-116 IC(50)=34 nM and tubulin polymerization IC(50) â¼1 µM). While the nitrile group at the alkene terminus was generally required for potent antiproliferative activity, its replacement was tolerated if there was a hydroxyl or amino group on one of the aryl rings. Conveniently, this group could also serve as a handle for amino acid derivatization to improve the compounds' solubility. The glycinamide analog 45 showed significant efficacy in the HCT-116 xenograft model, with 64% inhibition of tumor growth upon dosing at 20 mg/kg qd.
Asunto(s)
Alquenos/química , Alquenos/farmacología , Antineoplásicos/química , Derivados del Benceno/química , Derivados del Benceno/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Inhibidores de Fosfodiesterasa/química , Moduladores de Tubulina/química , Alquenos/síntesis química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Derivados del Benceno/síntesis química , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/metabolismo , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/metabolismo , Células HCT116 , Humanos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Ratones , Modelos Moleculares , Simulación de Dinámica Molecular , Inhibidores de Fosfodiesterasa/síntesis química , Inhibidores de Fosfodiesterasa/farmacología , Relación Estructura-Actividad , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/farmacologíaRESUMEN
In this communication, we report the discovery of 1S (apremilast), a novel potent and orally active phosphodiesterase 4 (PDE4) and tumor necrosis factor-alpha inhibitor. The optimization of previously reported 3-(1,3-dioxo-1,3-dihydroisoindol-2-yl)-3-(3,4-dimethoxyphenyl)propionic acid PDE4 inhibitors led to this series of sulfone analogues. Evaluation of the structure-activity relationship of substitutions on the phthalimide group led to the discovery of an acetylamino analogue 1S, which is currently in clinical trials.
Asunto(s)
Descubrimiento de Drogas , Inhibidores de Fosfodiesterasa 4 , Inhibidores de Fosfodiesterasa/farmacología , Talidomida/análogos & derivados , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Administración Oral , Animales , Humanos , Inhibidores de Fosfodiesterasa/administración & dosificación , Inhibidores de Fosfodiesterasa/química , Ratas , Estereoisomerismo , Relación Estructura-Actividad , Talidomida/administración & dosificación , Talidomida/química , Talidomida/farmacologíaRESUMEN
OBJECTIVES: Pancreatic cancer is one of the leading causes of cancer related deaths in the western world. It is also resistant to most chemotherapeutic modalities. Phosphodiesterase-4 inhibitors (PDE4is) have found applications in the treatment of respiratory diseases. The aim of this study is to investigate the cytotoxic effect of 2 novel PDE4is, the CC-8075 and CC-8062 compounds in pancreatic cancer cells. METHODS: Cell proliferation was measured using the sulforhodamine B protein dye. Induction of apoptosis was detected using enzyme-linked immunosorbent assay. Regulation of proteins and posttranslational modifications were determined using immunoblotting. RESULTS: Treatment of pancreatic cancer cells with CC-8075 and CC-8062 reduces their proliferation and increases apoptosis that is caspase dependent in T3M4 cells. Furthermore, PDE4is increase phosphorylation of p38MAPK, mitogen-activated protein kinase (MAPK) kinase 3/6,MAPKYactivated protein kinase 2, Atf2, and Hsp27. The use of thep38MAPK-specific inhibitors SB202190 and SB203580 results in a modest reduction in PDE4i-induced apoptosis in T3M4 cells. Also, retinoids enhance apoptosis induced by CC-8075 and CC-8062 in GER cells. CONCLUSIONS: These results highlight the antiproliferative effects of the phosphodiesterase inhibitors CC-8075 and CC-8062 in pancreatic cancer cells and suggest that activation of p38MAPK signaling pathway may be associated with this process.
Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/farmacología , Neoplasias Pancreáticas/patología , Inhibidores de Fosfodiesterasa 4 , Inhibidores de Fosfodiesterasa/farmacología , Alitretinoína , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Humanos , Imidazoles/farmacología , Neoplasias Pancreáticas/enzimología , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Transducción de Señal/efectos de los fármacos , Tretinoina/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Lenalidomide (Revlimid) is approved for the treatment of transfusion-dependent patients with anemia due to low- or intermediate-1-risk Myelodysplastic Syndromes (MDS) associated with a del 5q cytogenetic abnormality with or without additional cytogenetic abnormalities, and in combination with dexamethasone for the treatment of multiple myeloma patients who have received at least one prior therapy. Previous reports suggest that lenalidomide is anti-angiogenic and this property appears to be related to efficacy in patients with MDS. We have investigated the effect of lenalidomide on the formation of microvessels in a novel in vitro angiogenesis assay utilizing human umbilical arterial rings and in a capillary-like cord formation assay using cultured primary endothelial cells. We found that lenalidomide consistently inhibits both sprout formation by arterial rings and cord formation by endothelial cells in a dose-dependent manner. We also found an inhibitory effect of lenalidomide on the associations between cadherin 5, beta-catenin and CD31, adherens junction proteins whose interaction is critical for endothelial cell cord formation. Furthermore, lenalidomide inhibited VEGF-induced PI3K-Akt pathway signaling, which is known to regulate adherens junction formation. We also found a strong inhibitory effect of lenalidomide on hypoxia-induced endothelial cell formation of cords and HIF-1 alpha expression, the main mediator of hypoxia-mediated effects and a key driver of angiogenesis and metastasis. Anti-metastatic activity of lenalidomide in vivo was confirmed in the B16-F10 mouse melanoma model by a >40% reduction in melanoma lung colony counts versus untreated mice. Our results suggest that inhibitory effects on microvessel formation, in particular adherens junction formation and inhibition of hypoxia-induced processes support a potential anti-angiogenic and anti-metastatic mechanism for this clinically active drug.
Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Antineoplásicos/farmacología , Metástasis de la Neoplasia/prevención & control , Neovascularización Patológica/prevención & control , Talidomida/análogos & derivados , Uniones Adherentes/efectos de los fármacos , Animales , Antígenos CD/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Cadherinas/metabolismo , Diferenciación Celular/efectos de los fármacos , Hipoxia de la Célula , Línea Celular Tumoral , Células Cultivadas , Células Endoteliales/efectos de los fármacos , Células Endoteliales/patología , Femenino , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Técnicas In Vitro , Lenalidomida , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Melanoma Experimental/tratamiento farmacológico , Ratones , Microcirculación/efectos de los fármacos , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Embarazo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Talidomida/farmacología , Arterias Umbilicales/efectos de los fármacos , Arterias Umbilicales/crecimiento & desarrollo , beta Catenina/metabolismoRESUMEN
5,6-Dimethylxanthenone-4-acetic acid (DMXAA) is an antivascular drug that induces tumor necrosis factor (TNF) in mice. Thalidomide inhibits TNF induction by DMXAA and also potentiates its antitumor activity. We investigated whether these effects were enantiomer specific, using the R- or S-enantiomers of two nonracemizable thalidomide analogues. Racemic 3-fluorothalidomide (3FThal) and racemic 3-methylthalidomide (3MeThal) were separated into enantiomers of greater than 98% optical purity using preparative chiral column chromatography. C57Bl/6 mice implanted with subcutaneous Colon 38 tumors were treated with DMXAA (25 mg/kg) alone or together with the pure R- or S-enantiomers by a single i.p. injection. TNF levels in the serum or tumor tissues 3 h after treatment were measured using ELISAs and tumor growth was also measured. 3FThal and 3MeThal, at their respective single maximum tolerated doses (MTD) of 15 and 50 mg/kg, were more toxic in mice than thalidomide (100 mg/kg). The R- and S-enantiomers of either 3FThal or 3MeThal, at their respective MTD, inhibited DMXAA-induced TNF activity in serum and tumor tissue, but no significant differences were observed between the enantiomers. Coadministration of racemic or enantiomers of 3FThal or 3MeThal at their respective MTD did not potentiate the antitumor responses above that obtained with DMXAA alone, and no enantioselectivity was apparent. We conclude that there is no advantage in using the nonracemizable thalidomide analogues to improve the antitumor activity of DMXAA.
Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Talidomida/uso terapéutico , Factor de Necrosis Tumoral alfa/biosíntesis , Xantonas/uso terapéutico , Inhibidores de la Angiogénesis/administración & dosificación , Animales , Neoplasias del Colon/metabolismo , Sinergismo Farmacológico , Ensayo de Inmunoadsorción Enzimática , Femenino , Inyecciones Intraperitoneales , Dosis Máxima Tolerada , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Trasplante de Neoplasias , Estereoisomerismo , Relación Estructura-Actividad , Talidomida/administración & dosificación , Talidomida/análogos & derivados , Talidomida/química , Resultado del Tratamiento , Xantonas/administración & dosificaciónRESUMEN
Selective cytokine inhibitory drugs (SelCIDs) are a novel class of phosphodiesterase 4 inhibitors discovered during a thalidomide analog discovery program. These analogs were evaluated for their ability to inhibit tumor angiogenesis, vascularity, and growth. Two analogs (CC-7034 and CC-9088) were identified that had enhanced antiangiogenic activity in Matrigel assays compared with parental thalidomide. These analogs also inhibited the growth of established K1735 and RENCA murine tumors. Tumors whose growth was suppressed by SelCID treatment exhibited decreased vessel density together with increased tumor cell hypoxia and death. The decrease in vascularity produced by SelCID treatment is attributed to a selective loss of vessels devoid of pericyte coverage, suggesting that these agents target immature tumor vessels. That tumor cell death was localized to relatively avascular or hypoxic areas, coupled with the fact that none of the analogs was cytotoxic in vitro against the tumor cells, demonstrates that these analogs are novel antivascular agents with potent antitumor activity.
Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Citocinas/antagonistas & inhibidores , Endotelio Vascular/efectos de los fármacos , Neoplasias Experimentales/irrigación sanguínea , Neovascularización Patológica/tratamiento farmacológico , Talidomida/análogos & derivados , Animales , División Celular/efectos de los fármacos , Hipoxia de la Célula/fisiología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Talidomida/farmacologíaRESUMEN
Thalidomide, (1), has made a remarkable comeback from its days of a sedative with teratogenic properties due to its ability to selectively inhibit TNF-alpha, a key pro-inflammatory cytokine and its clinical benefit in the treatment of cancer. Thalidomide contains one chiral center and is known to be chirally unstable under in vitro and in vivo conditions. It has been hypothesized that different biological properties are associated with each isomer. Thus, chirally stable analogues of thalidomide, alpha-fluorothalidomide, (3) and alpha-fluoro-4-aminothalidomide (4) were prepared by electrophilic fluorination. Analogue 3 was found to be cytotoxic and did not inhibit TNF-alpha production in LPS stimulated hPBMC below toxic concentrations. On the other hand, 4 was non-cytotoxic at the tested concentrations and was found to be 830-fold more potent than thalidomide as TNF-alpha inhibitor.
Asunto(s)
Flúor/química , Talidomida/química , Células Cultivadas , Humanos , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Talidomida/farmacología , Factor de Necrosis Tumoral alfa/biosíntesisRESUMEN
CC-4047 (Actimid) and CC-5013 (Revimid) belong to a class of thalidomide analogs collectively known as the immunomodulatory drugs (IMiDs), which are currently being assessed in the treatment of patients with multiple myeloma and other cancers. IMiDs potently enhance T cell and natural killer cell responses and inhibit tumor necrosis factor-alpha, interleukin (IL)-1 beta, and IL-12 production from LPS-stimulated peripheral blood mononuclear cells. However, the molecular mechanism of action for these compounds is unknown. Herein, we report on the ability of the IMiDs to up-regulate production of IL-2 from activated human CD4+ and CD8+ peripheral blood T cells, production of IL-2 and IFN-gamma from T helper (Th)1-type cells, and production of IL-5 and IL-10 from Th2-type cells. Elevation of IL-2 production from Jurkat T cells was observed as early as 6 h poststimulation and correlated with an increase in IL-2 promoter activity that was dependent upon the proximal but not the distal AP-1 binding site. The IMiDs enhanced AP-1-driven transcriptional activity 2- to 4-fold after 6 h of T cell stimulation, and their relative potencies for AP-1 activation correlated with their potencies for increased IL-2 production in Jurkat T cells and in CD4+ or CD8+ human peripheral blood T cells. The most potent of these IMiDs, CC-4047, had no effect on nuclear factor of activated T cells transcriptional activity, calcium signaling, or phosphorylation of extracellular signal-regulated kinase 1/2, c-Jun NH2-terminal kinase 1/2, p38 mitogen-activated protein kinase, or c-Jun/Jun D in Jurkat T cells. These data suggest that IMiDs increase T cell cytokine production by potentiating AP-1 transcriptional activity.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Citocinas/biosíntesis , Proteínas Proto-Oncogénicas , Linfocitos T/efectos de los fármacos , Talidomida/farmacología , Factor de Transcripción AP-1/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Calcineurina/metabolismo , Señalización del Calcio , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Humanos , Interleucina-2/biosíntesis , Proteínas Quinasas JNK Activadas por Mitógenos , Janus Quinasa 2 , Células Jurkat , Antígenos Comunes de Leucocito/metabolismo , Activación de Linfocitos , MAP Quinasa Quinasa 1 , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosforilación , Regiones Promotoras Genéticas , Proteína Quinasa C/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Linfocitos T/metabolismo , Células TH1/metabolismo , Células Th2/metabolismo , Talidomida/análogos & derivados , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
Thalidomide is clinically useful in a number of cancers. Antitumor activity may be related to a number of known properties, including anti-tumor necrosis factor (TNF)-alpha and T-cell costimulatory and antiangiogenic activities. However, it may also involve direct antitumor effects. A series of second generation thalidomide analogues have been separated into two distinct groups of compounds, each with enhanced therapeutic potential, i.e., SelCIDs, which are phosphodiesterase (PDE) type IV inhibitors, and IMiDs, which have unknown mechanism(s) of action. We report here our efforts to determine direct antitumor effects of thalidomide and compounds from both groups. We found that one of the SelCID analogues (SelCID-3) was consistently effective at reducing tumor cell viability in a variety of solid tumor lines but had no effect on non-neoplastic cells. The antitumor activity was independent of known PDE4 inhibitory activity and did not involve cAMP elevation. Growth arrest was preceded by the early induction of G(2)-M cell cycle arrest, which led to caspase 3 mediated apoptosis. This was associated with increased expression of pro-apoptotic proteins and decreased expression of antiapoptotic bcl-2. Furthermore, extensive apoptosis in vivo was detected during SelCID-3-mediated inhibition of tumor growth in a murine xenotransplantation cancer model. Our results suggest that SelCID-3 represents a novel antitumor agent distinct from thalidomide and from previously characterized analogues with therapeutic potential against a range of solid tumors. This effect appears to be mediated via alterations in the expression of bcl-2 family proteins.