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BACKGROUND: Psoriasis involving challenging body areas, such as the scalp, face, palmoplantar surfaces, or nails, can be challenging to treat and negatively affects patient outcomes. OBJECTIVE: To assess clear responses and cumulative clinical benefits over 5 years of ixekizumab treatment of moderate-to-severe plaque psoriasis in patients with and without baseline involvement of challenging body areas. METHODS: This post hoc analysis included patients treated with ixekizumab in the UNCOVER-3 trial. We assessed PASI100 responses through the week (W) 264 and cumulative clinical benefits at W264 (calculated as least-squares mean of the percentage of maximum area under the curve for PASI100 and PASI% improvement and expressed as cumulative clearance days). Statistical differences were calculated via ANCOVA. RESULTS: A total of 385 patients were analyzed: 349 with scalp involvement, 152 with facial involvement, 96 with palmoplantar involvement, and 229 with nail involvement. Proportions of patients achieving PASI100 were numerically similar between patients with and without scalp and nail involvement. More patients without facial and palmoplantar involvement achieved PASI100 at W60 (only palmoplantar), W108, W156, W204, and W264 (only palmoplantar). At W264, cumulative clinical benefits for PASI100 and PASI% improvement were high and similar in both patient groups, with and without challenging body areas. A significant difference (P=0.006) was only observed for PASI% improvement between patients with and without nail involvement. CONCLUSION: For most efficacy measures, patients treated with ixekizumab over 5 years achieved similar clear responses and cumulative clinical benefits regardless of baseline involvement of challenging body areas. J Drugs Dermatol. 2024;23(8):619-625. doi:10.36849/JDD.8160.
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Anticorpos Monoclonais Humanizados , Psoríase , Humanos , Psoríase/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Masculino , Feminino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto , Índice de Gravidade de Doença , Fármacos Dermatológicos/uso terapêutico , Fármacos Dermatológicos/administração & dosagem , Fatores de TempoRESUMO
BACKGROUND: Long-term efficacy, safety, and quality of life with ixekizumab (IXE) through 5 years in UNCOVER-1 and UNCOVER-2 patients with baseline scalp, nail, or palmoplantar psoriasis were assessed. METHODS: Patients included in this intent-to-treat subanalysis had baseline involvement in at least one of the three anatomic areas (scalp, fingernail, or palmoplantar locations) and 1) received IXE through week 60, with a 160-mg starting dose 80 mg Q2W through week 12 and Q4W thereafter, 2) achieved a static Physician’s Global Assessment score of 0 or 1 at week 12, and 3) completed week 60 and continued treatment with IXE Q4W or were escalated to Q2W during the long-term extension. Efficacy outcomes (e.g., percent improvement in Psoriasis Scalp Severity Index [PSSI], Nail Psoriasis Severity Index [NAPSI], Palmoplantar Psoriasis Area and Severity [PPASI], and Dermatology Life Quality Index [DLQI]) were summarized by descriptive statistics through week 264. RESULTS: Patients rapidly achieved and sustained improvements in scalp, nail, and palmoplantar psoriasis for up to 5 years with IXE. Patients achieved complete clearance at year 5: observed (scalp, 82%; nail, 73%; palmoplantar, 96%) and mNRI (scalp, 77%; nail, 67%; palmoplantar, 85%). Up to 80% of patients reported DLQI 0,1 responses at week 12, which were sustained through week 264. No increases in the number of annual treatment-emergent adverse events were observed from years 1–5. CONCLUSION: Patients receiving IXE for 5 years sustained high rates of improvement in scalp, nail, and palmoplantar psoriasis, with a long-term quality of life benefit with no unexpected safety signals. J Drugs Dermatol. 2021;20(8):880-887. doi:10.36849/JDD.6101.
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Psoríase , Fármacos Dermatológicos/efeitos adversos , Método Duplo-Cego , Etanercepte , Humanos , Psoríase/diagnóstico , Psoríase/tratamento farmacológico , Qualidade de Vida , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
Purpose Approximately 3% of lung cancer bears mutations leading to MET exon 14 skipping, an oncogenic driver which is further evidenced by case reports of patient response to MET kinase inhibitor treatment. Approximately 15% of tumors harboring MET exon14 skipping have concurrent MET amplification. Experimental Design Merestinib is a type II MET kinase inhibitor. Emibetuzumab, a bivalent anti-MET antibody, internalizes MET receptor. Each single agent and the combination were evaluated in the Hs746t gastric cancer line bearing MET exon14 skipping and MET amplification. Results Merestinib inhibited Hs746t cell proliferation (IC50=34 nM) and totally eliminated pMET at 100nM. Emibetuzumab showed little anti-proliferative activity against Hs746t cells (IC50>100nM), did not reduce pMET, and slightly reduced cell surface MET. In the Hs746t xenograft model, dose dependent differences in durability of response were seen with merestinib including durable tumor regression (91.8%) at 12 mg/kg qd. Emibetuzumab treatment (10mg/kg qw) provided transient tumor regression (37.7%), but tumors re-grew while on treatment. Concurrent combination of merestinib (6 mg/kg qd) and emibetuzumab resulted in 85% tumor regression, while a sequential combination (initiating merestinib first) resulted in longer duration of treatment response. Conclusions Data in this study support a clinical evaluation of merestinib in patients with MET exon 14 skipping (NCT02920996). As a type II MET kinase inhibitor, merestinib may provide a therapeutic option to treatment naïve patients or to patients who progress on type I MET inhibitor treatment. Data also support clinical evaluation of the sequential combination of merestinib with emibetuzumab when patients progress on single agent merestinib.
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Anticorpos Biespecíficos/farmacologia , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos/farmacologia , Éxons/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Nus , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismoRESUMO
Mnk kinases regulate the phosphorylation and activation of the eukaryotic initiation factor 4E (eIF4E), a protein that plays key roles in the initiation of messenger RNA translation and whose activity is critical for various cellular functions. eIF4E is deregulated in acute myeloid leukemia (AML), and its aberrant activity contributes to leukemogenesis. We determined whether cercosporamide, an antifungal agent that was recently shown to act as a unique Mnk inhibitor, exhibits antileukemic properties. Treatment of AML cells with cercosporamide resulted in a dose-dependent suppression of eIF4E phosphorylation. Such suppression of Mnk kinase activity and eIF4E phosphorylation by cercosporamide resulted in dose-dependent suppressive effects on primitive leukemic progenitors (CFU-L) from AML patients and enhanced the antileukemic properties of cytarabine (Ara-C) or mammalian target of rapamycin (mTOR) complex 1 inhibition. Similarly, the combination of cercosporamide with cytarabine resulted in enhanced antileukemic responses in a xenograft mouse model in vivo. Altogether, this work demonstrates that the unique Mnk inhibitor cercosporamide suppresses phosphorylation of eIF4E and exhibits antileukemic effects, in support of future clinical-translational efforts involving combinations of Mnk inhibitors with cytarabine and/or mTOR inhibitors for the treatment of AML.
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Adenosina Trifosfatases/antagonistas & inibidores , Antineoplásicos/uso terapêutico , Benzofuranos/uso terapêutico , Proteínas de Transporte de Cátions/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , ATPases Transportadoras de Cobre , Regulação para Baixo/efeitos dos fármacos , Humanos , Células K562 , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células U937 , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The HGF/MET signaling pathway regulates a wide variety of normal cellular functions that can be subverted to support neoplasia, including cell proliferation, survival, apoptosis, scattering and motility, invasion, and angiogenesis. MET over-expression (with or without gene amplification), aberrant autocrine or paracrine ligand production, and missense MET mutations are mechanisms that lead to activation of the MET pathway in tumors and are associated with poor prognostic outcome. We report here preclinical development of a potent, orally bioavailable, small-molecule inhibitor LY2801653 targeting MET kinase. LY2801653 is a type-II ATP competitive, slow-off inhibitor of MET tyrosine kinase with a dissociation constant (Ki) of 2 nM, a pharmacodynamic residence time (Koff) of 0.00132 min(-1) and t1/2 of 525 min. LY2801653 demonstrated in vitro effects on MET pathway-dependent cell scattering and cell proliferation; in vivo anti-tumor effects in MET amplified (MKN45), MET autocrine (U-87MG, and KP4) and MET over-expressed (H441) xenograft models; and in vivo vessel normalization effects. LY2801653 also maintained potency against 13 MET variants, each bearing a single-point mutation. In subsequent nonclinical characterization, LY2801653 was found to have potent activity against several other receptor tyrosine oncokinases including MST1R, FLT3, AXL, MERTK, TEK, ROS1, DDR1/2 and against the serine/threonine kinases MKNK1/2. The potential value of MET and other inhibited targets within a number of malignancies (such as colon, bile ducts, and lung) is discussed. LY2801653 is currently in phase 1 clinical testing in patients with advanced cancer (trial I3O-MC-JSBA, NCT01285037).
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Indazóis/farmacologia , Niacinamida/análogos & derivados , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Tetrazóis/farmacologia , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacologia , Disponibilidade Biológica , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Indazóis/administração & dosagem , Indazóis/química , Camundongos , Mutação/genética , Niacinamida/administração & dosagem , Niacinamida/química , Niacinamida/farmacologia , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-met/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Tetrazóis/administração & dosagem , Tetrazóis/química , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Unbiased informatics approaches have the potential to generate insights into uncharacterized signaling pathways in human disease. In this study, we generated longitudinal transcriptomic profiles of plaque psoriasis lesions from patients enrolled in a clinical trial of the anti-IL17A antibody ixekizumab (IXE). This dataset was then computed against a curated matrix of over 700 million data points derived from published psoriasis and signaling node perturbation transcriptomic and chromatin immunoprecipitation-sequencing datasets. We observed substantive enrichment within both psoriasis-induced and IXE-repressed gene sets of transcriptional targets of members of the MuvB complex, a master regulator of the mitotic cell cycle. These gene sets were similarly enriched for pathways involved in the regulation of the G2/M transition of the cell cycle. Moreover, transcriptional targets for MuvB nodes were strongly enriched within IXE-repressed genes whose expression levels correlated strongly with the extent and severity of the psoriatic disease. In models of human keratinocyte proliferation, genes encoding MuvB nodes were transcriptionally repressed by IXE, and depletion of MuvB nodes reduced cell proliferation. Finally, we made the expression and regulatory networks that supported this study available as a freely accessible, cloud-based hypothesis generation platform. Our study positions inhibition of MuvB signaling as an important determinant of the therapeutic impact of IXE in psoriasis.
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Fármacos Dermatológicos , Psoríase , Humanos , Fármacos Dermatológicos/farmacologia , Fármacos Dermatológicos/uso terapêutico , Método Duplo-Cego , Psoríase/tratamento farmacológico , Psoríase/genética , Psoríase/patologia , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Resultado do TratamentoRESUMO
INTRODUCTION: The aim of this work is to describe real-world biologic-experienced psoriasis patients initiating ixekizumab by prior biologic therapy status and compare the effectiveness of ixekizumab between patients who previously failed secukinumab and those who failed other biologics. We hypothesized that (1) clinical outcomes and patient-reported outcomes would improve following a switch to IXE, and (2) there would be no differences in responses between patients who previously failed secukinumab and those who failed other biologics. METHODS: Participants (n = 419) included adult psoriasis patients enrolled in the CorEvitas Psoriasis Registry through 9/10/20 who switched to ixekizumab after discontinuing another biologic. Patients were classified by the biologic used immediately prior to ixekizumab and reason for discontinuation: prior secukinumab failure; prior secukinumab non-failure; prior other biologic failure; and prior other biologic non-failure. Discontinuations for efficacy reasons were considered failures; all others were considered non-failures. Baseline descriptive statistics were calculated. Multivariable Poisson regression models estimated the likelihood of response of other failure relative to secukinumab failure. RESULTS: Mean age was 51 years; 48% were women. Psoriasis disease characteristics were similar across prior biologic groups. At 6-month follow-up, disease severity improved for all who initiated ixekizumab after discontinuing another biologic. Secukinumab failure patients who switched to ixekizumab achieved BSA ≤ 1 (49%), BSA ≤ 3 (59%), PASI75 (46%), PASI ≤ 3 (64%), and IGA ≤ 1 (40%). Other failure patients achieved BSA ≤ 1 (55%), BSA ≤ 3 (72%), PASI75 (59%), PASI ≤ 3 (74%), and IGA ≤ 1 (54%). In regression modeling, we observed patients in the other biologics failure group had an increased likelihood of achieving response for BSA ≤ 3, PASI75, PASI90, PASI100, and IGA ≤ 1 compared to patients who failed secukinumab. CONCLUSIONS: These findings suggest that patients with psoriasis who switch to ixekizumab after discontinuing another biologic demonstrate improvement in disease severity after six months. Patients who discontinued biologics other than secukinumab may be more likely to respond to ixekiziumab compared to those who switched from secukinumab.
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Expression of eukaryotic translation initiation factor 4E (eIF4E) is commonly elevated in human and experimental cancers, promoting angiogenesis and tumor growth. Elevated eIF4E levels selectively increase translation of growth factors important in malignancy (e.g., VEGF, cyclin D1) and is thereby an attractive anticancer therapeutic target. Yet to date, no eIF4E-specific therapy has been developed. Herein we report development of eIF4E-specific antisense oligonucleotides (ASOs) designed to have the necessary tissue stability and nuclease resistance required for systemic anticancer therapy. In mammalian cultured cells, these ASOs specifically targeted the eIF4E mRNA for destruction, repressing expression of eIF4E-regulated proteins (e.g., VEGF, cyclin D1, survivin, c-myc, Bcl-2), inducing apoptosis, and preventing endothelial cells from forming vessel-like structures. Most importantly, intravenous ASO administration selectively and significantly reduced eIF4E expression in human tumor xenografts, significantly suppressing tumor growth. Because these ASOs also target murine eIF4E, we assessed the impact of eIF4E reduction in normal tissues. Despite reducing eIF4E levels by 80% in mouse liver, eIF4E-specific ASO administration did not affect body weight, organ weight, or liver transaminase levels, thereby providing the first in vivo evidence that cancers may be more susceptible to eIF4E inhibition than normal tissues. These data have prompted eIF4E-specific ASO clinical trials for the treatment of human cancers.
Assuntos
Fator de Iniciação 4E em Eucariotos/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias/metabolismo , Neoplasias/terapia , Biossíntese de Proteínas/genética , Animais , Apoptose , Sequência de Bases , Células Cultivadas , Células Endoteliais/metabolismo , Fator de Iniciação 4E em Eucariotos/genética , Humanos , Camundongos , Neoplasias/irrigação sanguínea , Neoplasias/patologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Merestinib is an oral multi-kinase inhibitor targeting a limited number of oncokinases including MET, AXL, RON and MKNK1/2. Here, we report that merestinib inhibits neurotrophic receptor tyrosine kinases NTRK1/2/3 which are oncogenic drivers in tumors bearing NTRK fusion resulting from chromosomal rearrangements. Merestinib is shown to be a type II NTRK1 kinase inhibitor as determined by x-ray crystallography. In KM-12 cells harboring TPM3-NTRK1 fusion, merestinib exhibits potent p-NTRK1 inhibition in vitro by western blot and elicits an anti-proliferative response in two- and three-dimensional growth. Merestinib treatment demonstrated profound tumor growth inhibition in in vivo cancer models harboring either a TPM3-NTRK1 or an ETV6-NTRK3 gene fusion. To recapitulate resistance observed from type I NTRK kinase inhibitors entrectinib and larotrectinib, we generated NIH-3T3 cells exogenously expressing TPM3-NTRK1 wild-type, or acquired mutations G595R and G667C in vitro and in vivo. Merestinib blocks tumor growth of both wild-type and mutant G667C TPM3-NTRK1 expressing NIH-3T3 cell-derived tumors. These preclinical data support the clinical evaluation of merestinib, a type II NTRK kinase inhibitor (NCT02920996), both in treatment naïve patients and in patients progressed on type I NTRK kinase inhibitors with acquired secondary G667C mutation in NTRK fusion bearing tumors.
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Activation of protein kinase Cbeta (PKCbeta) has been repeatedly implicated in tumor-induced angiogenesis. The PKCbeta-selective inhibitor, Enzastaurin (LY317615.HCl), suppresses angiogenesis and was advanced for clinical development based upon this antiangiogenic activity. Activation of PKCbeta has now also been implicated in tumor cell proliferation, apoptosis, and tumor invasiveness. Herein, we show that Enzastaurin has a direct effect on human tumor cells, inducing apoptosis and suppressing the proliferation of cultured tumor cells. Enzastaurin treatment also suppresses the phosphorylation of GSK3betaser9, ribosomal protein S6(S240/244), and AKT(Thr308). Oral dosing with Enzastaurin to yield plasma concentrations similar to those achieved in clinical trials significantly suppresses the growth of human glioblastoma and colon carcinoma xenografts. As in cultured tumor cells, Enzastaurin treatment suppresses the phosphorylation of GSK3beta in these xenograft tumor tissues. Enzastaurin treatment also suppresses GSK3beta phosphorylation to a similar extent in peripheral blood mononuclear cells (PBMCs) from these treated mice. These data show that Enzastaurin has a direct antitumor effect and that Enzastaurin treatment suppresses GSK3beta phosphorylation in both tumor tissue and in PBMCs, suggesting that GSK3beta phosphorylation may serve as a reliable pharmacodynamic marker for Enzastaurin activity. With previously published reports, these data support the notion that Enzastaurin suppresses tumor growth through multiple mechanisms: direct suppression of tumor cell proliferation and the induction of tumor cell death coupled to the indirect effect of suppressing tumor-induced angiogenesis.
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Apoptose/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Indóis/farmacologia , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Animais , Processos de Crescimento Celular/efeitos dos fármacos , Neoplasias do Colo/enzimologia , Neoplasias do Colo/patologia , Feminino , Glioblastoma/enzimologia , Glioblastoma/patologia , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Nus , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Proteína Quinase C beta , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Proteína S6 Ribossômica/antagonistas & inibidores , Proteína S6 Ribossômica/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The progression of human prostate cancer from the initial androgen-dependent phase to androgen independence involves diminished apoptosis and a release from the cell cycle block triggered by androgen ablation therapy. FOXO transcription factors play a central role in promoting expression of proapoptotic and cell cycle regulatory genes (e.g., FasL and p27KIP1). Reduced FOXO function might, therefore, play a role in androgen-independent progression of human prostate cancer. Herein, we show that FOXO function is compromised in androgen-independent prostate cancer cells (LNAI) versus androgen-dependent LNCaP cells. The FOXO3a protein, the most highly expressed FOXO family member in prostate cancer cells, is hyperphosphorylated in LNAI cells. FOXO3a expression is also markedly reduced in these androgen-independent LNAI cells when compared with parental LNCaP cells. Together, reduced FOXO3a expression coupled to FOXO3a hyperphosphorylation would suppress FOXO transcriptional activity. Accordingly, activity of the FOXO-responsive p27KIP1 promoter is reduced 60% in these LNAI cells when compared with LNCaP cells. Moreover, mutation of a conserved FOXO response element suppresses p27KIP1 promoter activity, substantiating a regulatory role for this FOXO response element in p27KIP1 promoter transactivation. Finally, we show that the activity of a distinct FOXO-responsive promoter, the 3X-IRS promoter, is also reduced in LNAI cells. Collectively, these data show that reduced FOXO3a expression coupled to increased FOXO3a phosphorylation coincide with reduced FOXO-responsive promoter activity in androgen-independent LNAI cells when compared with androgen-dependent LNCaP cells. To the extent that this model reflects human disease, these data suggest that FOXO function may be compromised with androgen-independent progression of human prostate cancer.
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Androgênios/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Fatores de Transcrição/metabolismo , Ativação Transcricional , Proteínas Supressoras de Tumor/genética , Western Blotting , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p27 , Progressão da Doença , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead , Humanos , Masculino , Fosforilação , Plasmídeos/metabolismo , Regiões Promotoras Genéticas , Neoplasias da Próstata/genética , Elementos de Resposta , Transdução de Sinais , Transfecção , Proteínas Supressoras de Tumor/metabolismoRESUMO
Fragile X syndrome (FXS) is the leading genetic cause of autism. Mutations in Fmr1 (fragile X mental retardation 1 gene) engender exaggerated translation resulting in dendritic spine dysmorphogenesis, synaptic plasticity alterations, and behavioral deficits in mice, which are reminiscent of FXS phenotypes. Using postmortem brains from FXS patients and Fmr1 knockout mice (Fmr1(-/y)), we show that phosphorylation of the mRNA 5' cap binding protein, eukaryotic initiation factor 4E (eIF4E), is elevated concomitant with increased expression of matrix metalloproteinase 9 (MMP-9) protein. Genetic or pharmacological reduction of eIF4E phosphorylation rescued core behavioral deficits, synaptic plasticity alterations, and dendritic spine morphology defects via reducing exaggerated translation of Mmp9 mRNA in Fmr1(-/y) mice, whereas MMP-9 overexpression produced several FXS-like phenotypes. These results uncover a mechanism of regulation of synaptic function by translational control of Mmp-9 in FXS, which opens the possibility of new treatment avenues for the diverse neurological and psychiatric aspects of FXS.
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Benzofuranos/farmacologia , Fator de Iniciação 4E em Eucariotos/fisiologia , Síndrome do Cromossomo X Frágil/tratamento farmacológico , Metaloproteinase 9 da Matriz/genética , Biossíntese de Proteínas/efeitos dos fármacos , Adenosina Trifosfatases/antagonistas & inibidores , Animais , Transtorno Autístico/enzimologia , Benzofuranos/uso terapêutico , Encéfalo/enzimologia , Proteínas de Transporte de Cátions/antagonistas & inibidores , Células Cultivadas , ATPases Transportadoras de Cobre , Espinhas Dendríticas/patologia , Indução Enzimática/efeitos dos fármacos , Feminino , Síndrome do Cromossomo X Frágil/enzimologia , Síndrome do Cromossomo X Frágil/genética , Humanos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Fosforilação , Processamento de Proteína Pós-Traducional , Receptores de Glutamato Metabotrópico/genética , Receptores de Glutamato Metabotrópico/metabolismoRESUMO
BACKGROUND: Aberrant cap-dependent translation is implicated in tumorigenesis in multiple tumor types including mesothelioma. In this study, disabling the eIF4F complex by targeting eIF4E with eIF4E-specific antisense oligonucleotide (4EASO) is assessed as a therapy for mesothelioma. METHODS: Mesothelioma cells were transfected with 4EASO, designed to target eIF4E mRNA, or mismatch-ASO control. Cell survival was measured in mesothelioma treated with 4EASO alone or combined with either gemcitabine or pemetrexed. Levels of eIF4E, ODC, Bcl-2 and ß-actin were assessed following treatment. Binding to a synthetic cap-analogue was used to study the strength of eIF4F complex activation following treatment. RESULTS: eIF4E level and the formation of eIF4F cap-complex decreased in response to 4EASO, but not mismatch control ASO, resulting in cleavage of PARP indicating apoptosis. 4EASO treatment resulted in dose dependent decrease in eIF4E levels, which corresponded to cytotoxicity of mesothelioma cells. 4EASO resulted in decreased levels of eIF4E in non-malignant LP9 cells, but this did not correspond to increased cytotoxicity. Proteins thought to be regulated by cap-dependent translation, Bcl-2 and ODC, were decreased upon treatment with 4EASO. Combination therapy of 4EASO with pemetrexed or gemcitabine further reduced cell number. CONCLUSION: 4EASO is a novel drug that causes apoptosis and selectively reduces eIF4E levels, eIF4F complex formation, and proliferation of mesothelioma cells. eIF4E knockdown results in decreased expression of anti-apoptotic and pro-growth proteins and enhances chemosensitivity.
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Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Fator de Iniciação 4F em Eucariotos/antagonistas & inibidores , Mesotelioma/genética , Oligonucleotídeos Antissenso/genética , RNA Mensageiro/antagonistas & inibidores , Actinas/genética , Actinas/metabolismo , Antineoplásicos/farmacologia , Apoptose , Contagem de Células , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação 4F em Eucariotos/genética , Fator de Iniciação 4F em Eucariotos/metabolismo , Expressão Gênica , Glutamatos/farmacologia , Guanina/análogos & derivados , Guanina/farmacologia , Humanos , Mesotelioma/metabolismo , Mesotelioma/patologia , Terapia de Alvo Molecular , Oligonucleotídeos Antissenso/metabolismo , Ornitina Descarboxilase/genética , Ornitina Descarboxilase/metabolismo , Pemetrexede , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Ligação Proteica , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transfecção , GencitabinaRESUMO
Activation of the translation initiation factor 4E (eIF4E) promotes malignant transformation and metastasis. Signaling through the AKT-mTOR pathway activates eIF4E by phosphorylating the inhibitory 4E binding proteins (4E-BP). This liberates eIF4E and allows binding to eIF4G. eIF4E can then be phosphorylated at serine 209 by the MAPK-interacting kinases (Mnk), which also interact with eIF4G. Although dispensable for normal development, Mnk function and eIF4E phosphorylation promote cellular proliferation and survival and are critical for malignant transformation. Accordingly, Mnk inhibition may serve as an attractive cancer therapy. We now report the identification of a potent, selective and orally bioavailable Mnk inhibitor that effectively blocks 4E phosphorylation both in vitro and in vivo. In cultured cancer cell lines, Mnk inhibitor treatment induces apoptosis and suppresses proliferation and soft agar colonization. Importantly, a single, orally administered dose of this Mnk inhibitor substantially suppresses eIF4E phosphorylation for at least 4 hours in human xenograft tumor tissue and mouse liver tissue. Moreover, oral dosing with the Mnk inhibitor significantly suppresses outgrowth of experimental B16 melanoma pulmonary metastases as well as growth of subcutaneous HCT116 colon carcinoma xenograft tumors, without affecting body weight. These findings offer the first description of a novel, orally bioavailable MNK inhibitor and the first preclinical proof-of-concept that MNK inhibition may provide a tractable cancer therapeutic approach.
Assuntos
Antineoplásicos/farmacologia , Benzofuranos/farmacologia , Fator de Iniciação 4E em Eucariotos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Neoplasias Pulmonares/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Sequência de Bases , Western Blotting , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Concentração Inibidora 50 , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Metástase Neoplásica/tratamento farmacológico , Fosforilação , Reação em Cadeia da Polimerase , Proteínas Serina-Treonina Quinases/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Enzastaurin (LY317615.HCl) is currently in a phase III registration trial for diffuse large B-Cell lymphoma and numerous phase II clinical trials. Enzastaurin suppresses angiogenesis and induces apoptosis in multiple human tumor cell lines by inhibiting protein kinase C (PKC) and phosphoinositide 3-kinase (PI3K)/AKT pathway signaling. PI3K/AKT pathway signaling liberates eukaryotic translation initiation factor 4E (eIF4E) through the hierarchical phosphorylation of eIF4E binding proteins (4E-BP). When hypophosphorylated, 4E-BPs associate with eIF4E, preventing eIF4E from binding eIF4G, blocking the formation of the eIF4F translation initiation complex. Herein, we show that enzastaurin treatment impacts signaling throughout the AKT/mTOR pathway leading to hypophosphorylation of 4E-BP1 in cancer cells of diverse lineages (glioblastoma, colon carcinoma, and B-cell lymphoma). Accordingly, enzastaurin treatment increases the amount of eIF4E bound to 4E-BP1 and decreases association of eIF4E with eIF4G, thereby reducing eIF4F translation initiation complex levels. We therefore chose to evaluate whether this effect on 4E-BP1 was involved in enzastaurin-induced apoptosis. Remarkably, enzastaurin-induced apoptosis was blocked in cancer cells depleted of 4E-BP1 by siRNAs, or in 4EBP1/2 knockout murine embryonic fibroblasts cells. Furthermore, eIF4E expression was increased and 4E-BP1 expression was decreased in cancer cells selected for reduced sensitivity to enzastaurin-induced apoptosis. These data highlight the importance of modulating 4E-BP1 function, and eIF4F complex levels, in the direct antitumor effect of enzastaurin and suggest that 4E-BP1 function may serve as a promising determinant of enzastaurin activity.
Assuntos
Apoptose/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Indóis/farmacologia , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Fator de Iniciação 4F em Eucariotos/metabolismo , Fatores de Iniciação em Eucariotos , Técnicas de Inativação de Genes , Humanos , Camundongos , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismoRESUMO
Elevated eukaryotic translation initiation factor 4E (eIF4E) function induces malignancy in experimental models by selectively enhancing translation of key malignancy-related mRNAs (c-myc and BCL-2). eIF4E activation may reflect increased eIF4E expression or phosphorylation of its inhibitory binding proteins (4E-BP). By immunohistochemical analyses of 148 tissues from 89 prostate cancer patients, we now show that both eIF4E expression and 4E-BP1 phosphorylation (p4E-BP1) are increased significantly, particularly in advanced prostate cancer versus benign prostatic hyperplasia tissues. Further, increased eIF4E and p4E-BP1 levels are significantly related to reduced patient survival, whereas uniform 4E-BP1 expression is significantly related to better patient survival. Both immunohistochemistry and Western blotting reveal that elevated eIF4E and p4E-BP1 are evident in the same prostate cancer tissues. In two distinct prostate cancer cell models, the progression to androgen independence also involves increased eIF4E activation. In these prostate cancer cells, reducing eIF4E expression with an eIF4E-specific antisense oligonucleotide currently in phase I clinical trials robustly induces apoptosis, regardless of cell cycle phase, and reduces expression of the eIF4E-regulated proteins BCL-2 and c-myc. Collectively, these data implicate eIF4E activation in prostate cancer and suggest that targeting eIF4E may be attractive for prostate cancer therapy.
Assuntos
Fator de Iniciação 4E em Eucariotos/biossíntese , Neoplasias da Próstata/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/fisiologia , Ciclo Celular/fisiologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Progressão da Doença , Fator de Iniciação 4E em Eucariotos/genética , Humanos , Imuno-Histoquímica , Masculino , Oligonucleotídeos Antissenso/genética , Fosfoproteínas/metabolismo , Fosforilação , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismoRESUMO
In multiple human cancers, the function of the eukaryotic translation initiation factor 4E (eIF4E) is elevated and directly related to disease progression. Overexpression or hyperactivation of eIF4E in experimental models can drive cellular transformation and malignant progression. Elevated eIF4E function triggers enhanced assembly of the eIF4F translation initiation complex and thereby drives cap-dependent translation. Though all capped mRNAs require eIF4F for translation, a pool of mRNAs are exceptionally dependent on elevated eIF4F activity for translation and are thereby selectively and disproportionately affected by altered eIF4F activity. These mRNAs encode proteins that play significant roles in all aspects of malignancy including angiogenesis factors (VEGF, FGF-2), onco-proteins (c-myc, cyclin D1, ODC), pro-survival proteins (survivin, BCL-2) and proteins involved in tumor invasion and metastasis (MMP-9, heparanase). Recent advances in targeting the eIF4F complex have highlighted the role for this complex in tumor cell survival and angiogenesis and have illuminated the enhanced susceptibility of the tumor cells to inhibition of the eIF4F complex. These studies have demonstrated the attractiveness and plausibility of targeting eIF4E and the eIF4F translation initiation complex for cancer therapy and have prompted the advance of the first eIF4E-specific therapy to the clinic.
Assuntos
Fator de Iniciação 4F em Eucariotos/antagonistas & inibidores , Neoplasias/terapia , Neovascularização Patológica/terapia , Proteínas Oncogênicas/antagonistas & inibidores , RNA Mensageiro/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Fator de Iniciação 4F em Eucariotos/genética , Fator de Iniciação 4F em Eucariotos/metabolismo , Humanos , Camundongos , Neoplasias/irrigação sanguínea , Neoplasias/metabolismo , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/uso terapêutico , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , RNA Mensageiro/biossínteseRESUMO
The eukaryotic translation initiation factor 4E (eIF4E) is frequently overexpressed in human cancers in relation to disease progression and drives cellular transformation, tumorigenesis, and metastatic progression in experimental models. Enhanced eIF4E function results from eIF4E overexpression and/or activation of the ras and phosphatidylinositol 3-kinase/AKT pathways and selectively increases the translation of key mRNAs involved in tumor growth, angiogenesis, and cell survival. Consequently, by simultaneously and selectively reducing the expression of numerous potent growth and survival factors critical for malignancy, targeting eIF4E for inhibition may provide an attractive therapy for many different tumor types. Recent work has now shown the plausibility of therapeutically targeting eIF4E and has resulted in the advance of the first eIF4E-specific therapy to clinical trials. These studies illustrate the increased susceptibility of tumor tissues to eIF4E inhibition and support the notion that the enhanced eIF4E function common to many tumor types may represent an Achilles' heel for cancer.