RESUMEN
Xenograft mice are largely used to evaluate the efficacy of oncological drugs during preclinical phases of drug discovery and development. Mathematical models provide a useful tool to quantitatively characterize tumor growth dynamics and also optimize upcoming experiments. To the best of our knowledge, this is the first report where unperturbed growth of a large set of tumor cell lines (n = 28) has been systematically analyzed using a previously proposed model of nonlinear mixed effects (NLME). Exponential growth was identified as the governing mechanism in the majority of the cell lines, with constant rate values ranging from 0.0204 to 0.203 day-1 No common patterns could be observed across tumor types, highlighting the importance of combining information from different cell lines when evaluating drug activity. Overall, typical model parameters were precisely estimated using designs in which tumor size measurements were taken every 2 days. Moreover, reducing the number of measurements to twice per week, or even once per week for cell lines with low growth rates, showed little impact on parameter precision. However, a sample size of at least 50 mice is needed to accurately characterize parameter variability (i.e., relative S.E. values below 50%). This work illustrates the feasibility of systematically applying NLME models to characterize tumor growth in drug discovery and development, and constitutes a valuable source of data to optimize experimental designs by providing an a priori sampling window and minimizing the number of samples required.
Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Ratones , Modelos EstadísticosRESUMEN
In this work, a semimechanistic tumor growth-response model for gemcitabine in pancreatic (administered as single agent) and ovarian (given as single agent and in combination with carboplatin) cancer in mice was developed. Tumor profiles were obtained from nude mice, previously inoculated with KP4, ASPC1, MIA PACA2, PANC1 (pancreas), A2780, or SKOV3×luc (ovarian) cell lines, and then treated with different dosing schedules of gemcitabine and/or carboplatin. Data were fitted using the population approach with Nonlinear Mixed Effect Models 7.2. In addition to cell proliferation, the tumor progression model for both types of cancer incorporates a carrying capacity representing metabolite pool for DNA synthesis required to tumor growth. Analysis of data from the treated groups revealed that gemcitabine exerted its tumor effects by promoting apoptosis as well as decreasing the carrying capacity compartment. Pharmacodynamic parameters were cell-specific and overall had similar range values between cancer types. In pancreas, a linear model was used to describe both gemcitabine effects with parameter values between 3.26 × 10-2 and 4.2 × 10-1 L/(mg × d). In ovarian cancer, the apoptotic effect was driven by an EMAX model with an efficacy/potency ratio of 5.25-8.65 L/(mg × d). The contribution of carboplatin to tumor effects was lower than the response exerted by gemcitabine and was incorporated in the model as an inhibition of the carrying capacity. The model developed was consistent in its structure across different tumor cell lines and two tumor types where gemcitabine is approved. Simulation-based evaluation diagnostics showed that the model performed well in all experimental design scenarios, including dose, schedule, and tumor type.
Asunto(s)
Carboplatino , Desoxicitidina/análogos & derivados , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Pancreáticas/tratamiento farmacológico , Animales , Antimetabolitos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptosis/efectos de los fármacos , Carboplatino/administración & dosificación , Carboplatino/farmacocinética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Desoxicitidina/administración & dosificación , Desoxicitidina/farmacocinética , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Xenoinjertos/efectos de los fármacos , Xenoinjertos/patología , Ratones , Ratones Desnudos , Neoplasias Ováricas/patología , Neoplasias Pancreáticas/patología , GemcitabinaRESUMEN
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 Trifosfatasas/antagonistas & inhibidores , Antineoplásicos/uso terapéutico , Benzofuranos/uso terapéutico , Proteínas de Transporte de Catión/antagonistas & inhibidores , Leucemia Mieloide Aguda/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , ATPasas Transportadoras de Cobre , Regulación hacia Abajo/efectos de los fármacos , Humanos , Células K562 , Ratones , Células Madre Neoplásicas/efectos de los fármacos , Células U937 , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Prasugrel, a thienopyridine ADP receptor antagonist, is an orally administered prodrug requiring in vivo metabolism to form the active metabolite that irreversibly inhibits platelet activation and aggregation mediated by the P2Y12[sub 12] receptor. A comprehensive nonclinical safety assessment including genotoxicity and carcinogenicity studies supported the chronic use of prasugrel in patients with atherothrombotic disease. In addition, a special assessment of the potential for prasugrel to enhance tumor growth was undertaken to address regulatory concerns relating to increases in human cancers. Prasugrel demonstrated no evidence of genotoxicity and was not oncogenic in a 2-year rat carcinogenicity study. In the 2-year mouse study, an increase in hepatocellular adenomas was considered secondary to enzyme induction and not relevant to human safety. Further, the absence of any increase in common background tumors at any other organ site in either rodent study indicated a lack of tumor promoting activity (apart from the CYP450 induction-related increase in mouse liver tumors). Cell culture studies with 3 human tumor cell lines (lung, colon, prostate) demonstrated that exposure of serum-starved cells to prasugrel's active and major circulating human metabolites does not increase cell proliferation relative to starved cells stimulated to proliferate by addition of 10% FBS. Prasugrel also did not increase tumor growth relative to vehicle controls in nude mice implanted with 3 human tumor cell lines. Thus, traditional genotoxicity and 2-year bioassays as well as specially designed tumor growth enhancement studies in human tumor cell lines and mouse xenograft models clearly demonstrated prasugrel's lack of tumorigenic potential.
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Plaquetas/efectos de los fármacos , Carcinógenos/toxicidad , Piperazinas/efectos adversos , Inhibidores de Agregación Plaquetaria/efectos adversos , Tiofenos/efectos adversos , Adenoma de Células Hepáticas/patología , Animales , Plaquetas/metabolismo , Carcinógenos/administración & dosificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Endogámicos ICR , Piperazinas/administración & dosificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Clorhidrato de Prasugrel , Ratas , Ratas Endogámicas F344 , Factores de Riesgo , Tiofenos/administración & dosificación , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Well-behaved, in vitro bioassays generally produce normally distributed values in their primary (efficacy) data. Accordingly, the best practices for statistical analysis are well documented and understood. However, assays may occasionally display unusually high variability and fall outside the assumptions inherent in these standard analyses. These assays may still be in the optimization phase, in which the source of variation could be identified and addressed. They might also represent the best available option to address the biological process being examined. In these cases, the use of robust statistical methods may provide a more appropriate set of tools for both data analysis and assay optimization. This article provides guidance on best practices for the use of robust statistical methods for the analysis of bioassay data as an alternative to standard methods. Impacts on experimental design and interpretation will be discussed.
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Bioensayo/métodosRESUMEN
The combined influence of oncogenic drivers, genomic instability, and/or DNA damage repair deficiencies increases replication stress in cancer. Cells with high replication stress rely on the upregulation of checkpoints like those governed by CHK1 for survival. Previous studies of the CHK1 inhibitor prexasertib demonstrated activity across multiple cancer types. Therefore, we sought to (1) identify markers of prexasertib sensitivity and (2) define the molecular mechanism(s) of intrinsic and acquired resistance using preclinical models representing multiple tumor types. Our findings indicate that while cyclin E dysregulation is a driving mechanism of prexasertib response, biomarkers associated with this aberration lack sufficient predictive power to render them clinically actionable for patient selection. Transcriptome analysis of a pan-cancer cell line panel and in vivo models revealed an association between expression of E2F target genes and prexasertib sensitivity and identified innate immunity genes associated with prexasertib resistance. Functional RNAi studies supported a causal role of replication fork components as modulators of prexasertib response. Mechanisms that protect cells from oncogene-induced replication stress may safeguard tumors from such stress induced by a CHK1 inhibitor, resulting in acquired drug resistance. Furthermore, resistance to prexasertib may be shaped by innate immunity.
RESUMEN
The aim of this evaluation was to predict tumour response to gemcitabine in patients with advanced pancreas or ovarian cancer using pre-clinical data obtained from xenograft tumour-bearing mice. The approach consisted of building a translational model combining pre-clinical pharmacokinetic-pharmacodynamic (PKPD) models and parameters, with dosing paradigms used in the clinics along with clinical PK models to derive tumour profiles in humans driving overall survival. Tumour growth inhibition simulations were performed using drug effect parameters obtained from mice, system parameters obtained from mice after appropriate scaling, patient PK models for gemcitabine and carboplatin, and the standard dosing schedules given in the clinical scenario for both types of cancers. Tumour profiles in mice were scaled by body weight to their equivalent values in humans. As models for survival in humans showed that tumour size was the main driver of the hazard rate, it was possible to describe overall survival in pancreatic and ovarian cancer patients. Simulated tumour dynamics in pancreatic and ovarian cancer patients were evaluated using available data from clinical trials. Furthermore, calculated metrics showed values (maximal tumour regression [0-17%] and tumour size ratio at week 12 with respect to baseline [- 9, - 4.5]) in the range of those predicted with the clinical PKPD models. The model-informed Drug Discovery and Development paradigm has been successfully applied retrospectively to gemcitabine data, through a semi-mechanistic translational approach, describing the time course of the tumour response in patients from pre-clinical studies.
Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Desoxicitidina/análogos & derivados , Modelos Biológicos , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Pancreáticas/tratamiento farmacológico , Animales , Antimetabolitos Antineoplásicos/uso terapéutico , Interpretación Estadística de Datos , Desoxicitidina/farmacología , Desoxicitidina/uso terapéutico , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Ratones , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , GemcitabinaRESUMEN
PURPOSE: Checkpoint kinase 1 (CHK1) inhibitors potentiate the DNA-damaging effects of cytotoxic therapies and/or promote elevated levels of replication stress, leading to tumor cell death. Prexasertib (LY2606368) is a CHK1 small-molecule inhibitor under clinical evaluation in multiple adult and pediatric cancers. In this study, prexasertib was tested in a large panel of preclinical models of pediatric solid malignancies alone or in combination with chemotherapy. EXPERIMENTAL DESIGN: DNA damage and changes in cell signaling following in vitro prexasertib treatment in pediatric sarcoma cell lines were analyzed by Western blot and high content imaging. Antitumor activity of prexasertib as a single agent or in combination with different chemotherapies was explored in cell line-derived (CDX) and patient-derived xenograft (PDX) mouse models representing nine different pediatric cancer histologies. RESULTS: Pediatric sarcoma cell lines were highly sensitive to prexasertib treatment in vitro, resulting in activation of the DNA damage response. Two PDX models of desmoplastic small round cell tumor and one malignant rhabdoid tumor CDX model responded to prexasertib with complete regression. Prexasertib monotherapy also elicited robust responses in mouse models of rhabdomyosarcoma. Concurrent administration with chemotherapy was sufficient to overcome innate resistance or prevent acquired resistance to prexasertib in preclinical models of neuroblastoma, osteosarcoma, and Ewing sarcoma, or alveolar rhabdomyosarcoma, respectively. CONCLUSIONS: Prexasertib has significant antitumor effects as a monotherapy or in combination with chemotherapy in multiple preclinical models of pediatric cancer. These findings support further investigation of prexasertib in pediatric malignancies.
Asunto(s)
Antineoplásicos/farmacología , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/antagonistas & inhibidores , Neoplasias/metabolismo , Neoplasias/patología , Inhibidores de Proteínas Quinasas/farmacología , Pirazinas/farmacología , Pirazoles/farmacología , Animales , Línea Celular Tumoral , Células Cultivadas , Niño , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Sinergismo Farmacológico , Humanos , Ratones , Neoplasias/tratamiento farmacológico , Sarcoma de Ewing , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Loss-of-function mutations in the retinoblastoma gene RB1 are common in several treatment-refractory cancers such as small-cell lung cancer and triple-negative breast cancer. To identify drugs synthetic lethal with RB1 mutation (RB1 mut), we tested 36 cell-cycle inhibitors using a cancer cell panel profiling approach optimized to discern cytotoxic from cytostatic effects. Inhibitors of the Aurora kinases AURKA and AURKB showed the strongest RB1 association in this assay. LY3295668, an AURKA inhibitor with over 1,000-fold selectivity versus AURKB, is distinguished by minimal toxicity to bone marrow cells at concentrations active against RB1 mut cancer cells and leads to durable regression of RB1 mut tumor xenografts at exposures that are well tolerated in rodents. Genetic suppression screens identified enforcers of the spindle-assembly checkpoint (SAC) as essential for LY3295668 cytotoxicity in RB1-deficient cancers and suggest a model in which a primed SAC creates a unique dependency on AURKA for mitotic exit and survival. SIGNIFICANCE: The identification of a synthetic lethal interaction between RB1 and AURKA inhibition, and the discovery of a drug that can be dosed continuously to achieve uninterrupted inhibition of AURKA kinase activity without myelosuppression, suggest a new approach for the treatment of RB1-deficient malignancies, including patients progressing on CDK4/6 inhibitors.See related commentary by Dick and Li, p. 169.This article is highlighted in the In This Issue feature, p. 151.
Asunto(s)
Aurora Quinasa A/antagonistas & inhibidores , Neoplasias de la Mama/patología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Puntos de Control de la Fase M del Ciclo Celular/efectos de los fármacos , Proteínas de Unión a Retinoblastoma/metabolismo , Carcinoma Pulmonar de Células Pequeñas/patología , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Antineoplásicos/farmacología , Apoptosis , Aurora Quinasa A/genética , Aurora Quinasa A/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Proliferación Celular , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Proteínas de Unión a Retinoblastoma/genética , Transducción de Señal , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Carcinoma Pulmonar de Células Pequeñas/metabolismo , Células Tumorales Cultivadas , Ubiquitina-Proteína Ligasas/genética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The aim of this evaluation was to characterize the impact of the tumour size (TS) effects driven by the anticancer drug gemcitabine on overall survival (OS) in patients with advanced pancreatic cancer by building and validating a predictive semi-mechanistic joint TS-OS model. TS and OS data were obtained from one phase II and one phase III study where gemcitabine was administered (1000-1250â¯mg/kg over 30-60â¯min i.v infusion) as single agent to patients (nâ¯=â¯285) with advanced pancreatic cancer. Drug exposure, TS and OS were linked using the population approach with NONMEM 7.3. Pancreatic tumour progression was characterized by exponential growth (doubling timeâ¯=â¯67â¯weeks), and tumour response to treatment was described as a function of the weekly area under the gemcitabine triphosphate concentration vs time curve (AUC), including treatment-related resistance development. The typical predicted percentage of tumour growth inhibition with respect to no treatment was 22.3% at the end of 6 chemotherapy cycles. Emerging resistance elicited a 57% decrease in drug effects during the 6th chemotherapy cycle. Predicted TS profile was identified as main prognostic factor of OS, with tumours responders' profiles improving median OS by 30â¯weeks compared to stable-disease TS profiles. Results of NCT00574275 trial were predicted using this modelling framework, thereby validating the approach as a prediction tool in clinical development. Our analyses show that despite the advanced stage of the disease in this patient population, the modelling framework herein can be used to predict the likelihood of treatment success using early clinical data.
Asunto(s)
Antineoplásicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Desoxicitidina/uso terapéutico , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Páncreas/efectos de los fármacos , Páncreas/patología , Neoplasias Pancreáticas/patología , Pronóstico , Resultado del Tratamiento , GemcitabinaRESUMEN
BACKGROUND: TGFß signaling plays a pleotropic role in tumor biology, promoting tumor proliferation, invasion and metastasis, and escape from immune surveillance. Inhibiting TGFß's immune suppressive effects has become of particular interest as a way to increase the benefit of cancer immunotherapy. Here we utilized preclinical models to explore the impact of the clinical stage TGFß pathway inhibitor, galunisertib, on anti-tumor immunity at clinically relevant doses. RESULTS: In vitro treatment with galunisertib reversed TGFß and regulatory T cell mediated suppression of human T cell proliferation. In vivo treatment of mice with established 4T1-LP tumors resulted in strong dose-dependent anti-tumor activity with close to 100% inhibition of tumor growth and complete regressions upon cessation of treatment in 50% of animals. This effect was CD8+ T cell dependent, and led to increased T cell numbers in treated tumors. Mice with durable regressions rejected tumor rechallenge, demonstrating the establishment of immunological memory. Consequently, mice that rejected immunogenic 4T1-LP tumors were able to resist rechallenge with poorly immunogenic 4 T1 parental cells, suggesting the development of a secondary immune response via antigen spreading as a consequence of effective tumor targeting. Combination of galunisertib with PD-L1 blockade resulted in improved tumor growth inhibition and complete regressions in colon carcinoma models, demonstrating the potential synergy when cotargeting TGFß and PD-1/PD-L1 pathways. Combination therapy was associated with enhanced anti-tumor immune related gene expression profile that was accelerated compared to anti-PD-L1 monotherapy. CONCLUSIONS: Together these data highlight the ability of galunisertib to modulate T cell immunity and the therapeutic potential of combining galunisertib with current PD-1/L1 immunotherapy.
Asunto(s)
Terapia Combinada/métodos , Inmunoterapia/métodos , Pirazoles/uso terapéutico , Quinolinas/uso terapéutico , Factor de Crecimiento Transformador beta/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Pirazoles/farmacología , Quinolinas/farmacologíaRESUMEN
AICARFT is a folate dependent catalytic site within the ATIC gene, part of the purine biosynthetic pathway, a pathway frequently upregulated in cancers. LSN3213128 is a potent (16 nM) anti-folate inhibitor of AICARFT and selective relative to TS, SHMT1, MTHFD1, MTHFD2 and MTHFD2L. Increases in ZMP, accompanied by activation of AMPK and cell growth inhibition, were observed with treatment of LY3213128. These effects on ZMP and proliferation were dependent on folate levels. In human breast MDA-MB-231met2 and lung NCI-H460 cell lines, growth inhibition was rescued by hypoxanthine, but not in the A9 murine cell line which is deficient in purine salvage. In athymic nude mice, LSN3213128 robustly elevates ZMP in MDA-MB-231met2, NCI-H460 and A9 tumors in a time and dose dependent manner. Significant tumor growth inhibition in human breast MDA-MB231met2 and lung NCI-H460 xenografts and in the syngeneic A9 tumor model were observed with oral administration of LSN3213128. Strikingly, AMPK appeared activated within the tumors and did not change even at high levels of intratumoral ZMP after weeks of dosing. These results support the evaluation of LSN3213128 as an antineoplastic agent.
Asunto(s)
Aminoimidazol Carboxamida/análogos & derivados , Antineoplásicos , Inhibidores Enzimáticos/farmacología , Transferasas de Hidroximetilo y Formilo/antagonistas & inhibidores , Neoplasias Pulmonares , Complejos Multienzimáticos/antagonistas & inhibidores , Proteínas de Neoplasias/antagonistas & inhibidores , Nucleótido Desaminasas/antagonistas & inhibidores , Ribonucleótidos , Aminoimidazol Carboxamida/farmacocinética , Aminoimidazol Carboxamida/farmacología , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular Tumoral , Femenino , Humanos , Transferasas de Hidroximetilo y Formilo/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Complejos Multienzimáticos/metabolismo , Proteínas de Neoplasias/metabolismo , Nucleótido Desaminasas/metabolismo , Ribonucleótidos/farmacocinética , Ribonucleótidos/farmacología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Abemaciclib, an inhibitor of cyclin dependent kinases 4 and 6 (CDK4/6), has recently been approved for the treatment of hormone receptor-positive breast cancer. In this study, we use murine syngeneic tumor models and in vitro assays to investigate the impact of abemaciclib on T cells, the tumor immune microenvironment and the ability to combine with anti-PD-L1 blockade. Abemaciclib monotherapy resulted in tumor growth delay that was associated with an increased T cell inflammatory signature in tumors. Combination with anti-PD-L1 therapy led to complete tumor regressions and immunological memory, accompanied by enhanced antigen presentation, a T cell inflamed phenotype, and enhanced cell cycle control. In vitro, treatment with abemaciclib resulted in increased activation of human T cells and upregulated expression of antigen presentation genes in MCF-7 breast cancer cells. These data collectively support the clinical investigation of the combination of abemaciclib with agents such as anti-PD-L1 that modulate T cell anti-tumor immunity.
Asunto(s)
Aminopiridinas/uso terapéutico , Bencimidazoles/uso terapéutico , Inhibidor p15 de las Quinasas Dependientes de la Ciclina/uso terapéutico , Inhibidor p18 de las Quinasas Dependientes de la Ciclina/uso terapéutico , Receptor de Muerte Celular Programada 1/metabolismo , Aminopiridinas/farmacología , Bencimidazoles/farmacología , Inhibidor p15 de las Quinasas Dependientes de la Ciclina/farmacología , Inhibidor p18 de las Quinasas Dependientes de la Ciclina/farmacología , Humanos , Microambiente TumoralRESUMEN
Transforming growth factor-ß (TGFß) is an important driver of tumor growth via intrinsic and extrinsic mechanisms, and is therefore an attractive target for developing cancer therapeutics. Using preclinical models, we characterized the anti-tumor activity of a small molecule inhibitor of TGFß receptor I (TGFßRI), galunisertib (LY2157299 monohydrate). Galunisertib demonstrated potent and selective inhibition of TGFßRI with corresponding inhibition of downstream signaling via inhibition of SMAD phosphorylation (pSMAD). Galunisertib also inhibited TGFß-induced pSMAD in vivo, which enabled a pharmacokinetic/pharmacodynamic profile in Calu6 and EMT6-LM2 tumors. Galunisertib demonstrated anti-tumor activity including inhibition of tumor cell migration and mesenchymal phenotype, reversal of TGFß-mediated immune-suppression, and tumor growth delay. A concentration-effect relationship was established with a dosing schedule to achieve the optimal level of target modulation. Finally, a rat model demonstrated a correlation between galunisertib-dependent inhibition of pSMAD in tumor tissues and in PBMCs, supporting the use of PBMCs for assessing pharmacodynamic effects. Galunisertib has been tested in several clinical studies with evidence of anti-tumor activity observed in subsets of patients. Here, we demonstrate that galunisertib inhibits a number of TGFß-dependent functions leading to anti-tumor activity. The enhanced understanding of galunisertib provides rationale for further informed clinical development of TGFß pathway inhibitors.
RESUMEN
The Assay Guidance Manual (AGM) is an eBook of best practices for the design, development, and implementation of robust assays for early drug discovery. Initiated by pharmaceutical company scientists, the manual provides guidance for designing a "testing funnel" of assays to identify genuine hits using high-throughput screening (HTS) and advancing them through preclinical development. Combined with a workshop/tutorial component, the overall goal of the AGM is to provide a valuable resource for training translational scientists.
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Bioensayo/métodos , Descubrimiento de Drogas , Geografía , Ensayos Analíticos de Alto Rendimiento , Humanos , Investigación Biomédica TraslacionalRESUMEN
The splicing factor SPF45 (RBM17) is frequently overexpressed in many solid tumors, and stable expression in HeLa cells confers resistance to doxorubicin and vincristine. In this study, we characterized stable transfectants of A2780 ovarian carcinoma cells. In a 3-day cytotoxicity assay, human SPF45 overexpression conferred 3- to 21-fold resistance to carboplatin, vinorelbine, doxorubicin, etoposide, mitoxantrone, and vincristine. In addition, resistance to gemcitabine and pemetrexed was observed at the highest drug concentrations tested. Knockdown of SPF45 in parental A2780 cells using a hammerhead ribozyme sensitized A2780 cells to etoposide by approximately 5-fold relative to a catalytically inactive ribozyme control and untransfected cells, suggesting a role for SPF45 in intrinsic resistance to some drugs. A2780-SPF45 cells accumulated similar levels of doxorubicin as vector-transfected and parental A2780 cells, indicating that drug resistance is not due to differences in drug accumulation. Efforts to identify small molecules that could block SPF45-mediated drug resistance revealed that the selective estrogen receptor (ER) modulators tamoxifen and LY117018 (a raloxifene analogue) partially reversed SPF45-mediated drug resistance to mitoxantrone in A2780-SPF45 cells from 21-fold to 8- and 5-fold, respectively, but did not significantly affect the mitoxantrone sensitivity of vector control cells. Quantitative PCR showed that ERbeta but not ERalpha was expressed in A2780 transfectants. Coimmunoprecipitation experiments suggest that SPF45 and ERbeta physically interact in vivo. Thus, SPF45-mediated drug resistance in A2780 cells may result in part from effects of SPF45 on the transcription or alternate splicing of ERbeta-regulated genes.
Asunto(s)
Resistencia a Múltiples Medicamentos/fisiología , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/metabolismo , Proteínas de Unión al ARN/biosíntesis , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular Tumoral , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos , Receptor beta de Estrógeno/metabolismo , Etopósido/farmacocinética , Etopósido/farmacología , Femenino , Humanos , Mitoxantrona/farmacocinética , Mitoxantrona/farmacología , Neoplasias Ováricas/genética , Pirrolidinas/farmacología , Empalme del ARN , Factores de Empalme de ARN , ARN Catalítico/genética , ARN Catalítico/metabolismo , Proteínas de Unión al ARN/antagonistas & inhibidores , Proteínas de Unión al ARN/genética , Tamoxifeno/farmacología , Tiofenos/farmacología , TransfecciónRESUMEN
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.
Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Indoles/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Animales , Procesos de Crecimiento Celular/efectos de los fármacos , Neoplasias del Colon/enzimología , Neoplasias del Colon/patología , Femenino , Glioblastoma/enzimología , Glioblastoma/patología , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Células HCT116 , Humanos , Masculino , Ratones , Ratones Desnudos , Fosforilación/efectos de los fármacos , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/patología , Proteína Quinasa C beta , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Proteína S6 Ribosómica/antagonistas & inhibidores , Proteína S6 Ribosómica/metabolismo , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Purpose: To evaluate the antitumor efficacy of cetuximab in combination with LSN3074753, an analog of LY3009120 and pan-RAF inhibitor in 79 colorectal cancer patient-derived xenograft (PDX) models.Experimental Design: Seventy-nine well-characterized colorectal cancer PDX models were employed to conduct a single mouse per treatment group (n = 1) trial.Results: Consistent with clinical results, cetuximab was efficacious in wild-type KRAS and BRAF PDX models, with an overall response rate of 6.3% and disease control rate (DCR) of 20.3%. LSN3074753 was active in a small subset of PDX models that harbored KRAS or BRAF mutations. However, the combination treatment displayed the enhanced antitumor activity with DCR of 35.4%. Statistical analysis revealed that BRAF and KRAS mutations were the best predictors of the combinatorial activity and were significantly associated with synergistic effect with a P value of 0.01 compared with cetuximab alone. In 12 models with BRAF mutations, the combination therapy resulted in a DCR of 41.7%, whereas either monotherapy had a DCR of 8.3%. Among 44 KRAS mutation models, cetuximab or LSN3074753 monotherapy resulted in a DCR of 13.6% or 11.4%, respectively, and the combination therapy increased DCR to 34.1%. Molecular analysis suggests that EGFR activation is a potential feedback and resistant mechanism of pan-RAF inhibition.Conclusions: MAPK and EGFR pathway activations are two major molecular hallmarks of colorectal cancer. This mouse PDX trial recapitulated clinical results of cetuximab. Concurrent EGFR and RAF inhibition demonstrated synergistic antitumor activity for colorectal cancer PDX models with a KRAS or BRAF mutation. Clin Cancer Res; 23(18); 5547-60. ©2017 AACR.
Asunto(s)
Antineoplásicos/farmacología , Neoplasias Colorrectales/genética , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Proteínas Proto-Oncogénicas B-raf/genética , Animales , Biomarcadores de Tumor , Línea Celular Tumoral , Cetuximab/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Modelos Animales de Enfermedad , Quimioterapia Combinada , Receptores ErbB/metabolismo , Humanos , Ligandos , Ratones , Compuestos de Fenilurea/farmacología , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas B-raf/metabolismo , Pirimidinas/farmacología , Tasa de Supervivencia , Resultado del Tratamiento , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Most cancers preserve functional retinoblastoma (Rb) and may, therefore, respond to inhibition of D-cyclin-dependent Rb kinases, CDK4 and CDK6. To date, CDK4/6 inhibitors have shown promising clinical activity in breast cancer and lymphomas, but it is not clear which additional Rb-positive cancers might benefit from these agents. No systematic survey to compare relative sensitivities across tumor types and define molecular determinants of response has been described. We report a subset of cancers highly sensitive to CDK4/6 inhibition and characterized by various genomic aberrations known to elevate D-cyclin levels and describe a recurrent CCND1 3'UTR mutation associated with increased expression in endometrial cancer. The results suggest multiple additional classes of cancer that may benefit from CDK4/6-inhibiting drugs such as abemaciclib.
Asunto(s)
Aminopiridinas/farmacología , Bencimidazoles/farmacología , Ciclina D/metabolismo , Neoplasias/genética , Animales , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Ensayos Clínicos Fase I como Asunto , Ciclina D/genética , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
In this article, the authors compare the assay performance measures, signal window, Z' factor, and assay variability ratio. They examine their mathematical formulae for similarities and differences, describe their statistical sampling properties using the results of a computer simulation, and illustrate their use with example data. Based on these results, the authors recommend the Z' factor as a preferred measure of assay performance for screening assays and point out that none of these measures are adequate for characterizing concentration-response assays.