RESUMEN
Triple-negative breast cancer (TNBC) remains the most lethal subtype of breast cancer, characterized by poor response rates to current chemotherapies and a lack of additional effective treatment options. While approximately 30% of patients respond well to anthracycline- and taxane-based standard-of-care chemotherapy regimens, the majority of patients experience limited improvements in clinical outcomes, highlighting the critical need for strategies to enhance the effectiveness of anthracycline/taxane-based chemotherapy in TNBC. In this study, we report on the potential of a DNA-PK inhibitor, peposertib, to improve the effectiveness of topoisomerase II (TOPO II) inhibitors, particularly anthracyclines, in TNBC. Our in vitro studies demonstrate the synergistic antiproliferative activity of peposertib in combination with doxorubicin, epirubicin and etoposide in multiple TNBC cell lines. Downstream analysis revealed the induction of ATM-dependent compensatory signaling and p53 pathway activation under combination treatment. These in vitro findings were substantiated by pronounced anti-tumor effects observed in mice bearing subcutaneously implanted tumors. We established a well-tolerated preclinical treatment regimen combining peposertib with pegylated liposomal doxorubicin (PLD) and demonstrated strong anti-tumor efficacy in cell-line-derived and patient-derived TNBC xenograft models in vivo. Taken together, our findings provide evidence that co-treatment with peposertib has the potential to enhance the efficacy of anthracycline/TOPO II-based chemotherapies, and it provides a promising strategy to improve treatment outcomes for TNBC patients.
Asunto(s)
Sinergismo Farmacológico , Inhibidores de Topoisomerasa II , Neoplasias de la Mama Triple Negativas , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Femenino , Humanos , Ratones , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , ADN-Topoisomerasas de Tipo II/metabolismo , Proteína Quinasa Activada por ADN/antagonistas & inhibidores , Proteína Quinasa Activada por ADN/metabolismo , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Doxorrubicina/análogos & derivados , Epirrubicina/farmacología , Etopósido/farmacología , Etopósido/uso terapéutico , Polietilenglicoles/farmacología , Sulfonas/farmacología , Inhibidores de Topoisomerasa II/farmacología , Inhibidores de Topoisomerasa II/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patologíaRESUMEN
Anti-EGFR monoclonal antibodies (mAb) like Cetuximab are commonly used for treatment of EGFR+ solid tumors mainly by exerting their therapeutic effect through inhibition of signal transduction. Additionally, IgG1 is a potent mediator of antibody-dependent cytotoxicity (ADCC). In case of the IgG1, Cetuximab induction of ADCC in vivo is controversially discussed. In our study, we investigated the efficiency of Cetuximab-mediated ADCC in a humanized mouse tumor model in vivo and analyzed the contribution of immunologic processes toward antitumor activity. Therefore, we used immunodeficient NOD/Scid mice transgenic for human MHC class I molecule HLA-A2 and adoptively transferred human HLA-A2+ PBMC after engraftment of human epidermoid cell carcinoma A431. Here, we show that high doses of anti-EGFR mAb induced strong tumor regression independent of the immune system. However, tumor regression by low doses of anti-EGFR mAb treatment was ADCC dependent and mediated by tumor infiltrating CD8+ T effector cells. This novel mechanism of ADCC conducted by CD8+ T effector cells was restricted to IgG1 anti-EGFR mAb, dependent of binding to CD16 on T cells and could be inhibited after EGFR blockade on tumor cells. Furthermore, CD8+ T effector cell-mediated ADCC was enhanced in the presence of IL-15 and strongly improved after glycosylation of anti-EGFR mAb indicating the potential of glycoengineered therapeutic mAb as efficient biologicals in cancer therapy.
Asunto(s)
Citotoxicidad Celular Dependiente de Anticuerpos , Linfocitos T CD8-positivos/inmunología , Receptores ErbB/inmunología , Inmunoglobulina G/farmacología , Animales , Línea Celular Tumoral , Técnicas de Cocultivo , Receptores ErbB/antagonistas & inhibidores , Proteínas Ligadas a GPI/metabolismo , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Humanos , Inmunoglobulina G/uso terapéutico , Interleucina-15/fisiología , Ratones Endogámicos NOD , Ratones SCID , Receptores de IgG/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Synovial sarcoma is a rare and highly aggressive subtype of soft tissue sarcoma. The clinical challenge posed by advanced or metastatic synovial sarcoma, marked by limited treatment options and suboptimal outcomes, necessitates innovative approaches. The topoisomerase II (Topo II) inhibitor doxorubicin has remained the cornerstone systemic treatment for decades, and there is pressing need for improved therapeutic strategies for these patients. This study highlights the potential to enhance the cytotoxic effects of doxorubicin within well-characterized synovial sarcoma cell lines using the potent and selective DNA-PK inhibitor, peposertib. In vitro investigations unveil a p53-mediated synergistic anti-tumor effect when combining doxorubicin with peposertib. The in vitro findings were substantiated by pronounced anti-tumor effects in mice bearing subcutaneously implanted tumors. A well-tolerated regimen for the combined application was established using both pegylated liposomal doxorubicin (PLD) and unmodified doxorubicin. Notably, the combination of PLD and peposertib displayed enhanced anti-tumor efficacy compared to unmodified doxorubicin at equivalent doses, suggesting an improved therapeutic window-a critical consideration for clinical translation. Efficacy studies in two patient-derived xenograft models of synovial sarcoma, accurately reflecting human metastatic disease, further validate the potential of this combined therapy. These findings align with previous evidence showcasing the synergy between DNA-PK inhibition and Topo II inhibitors in diverse tumor models, including breast and ovarian cancers. Our study extends the potential utility of combined therapy to synovial sarcoma.
RESUMEN
RAF kinase plays a critical role in the RAF-MEK-ERK signaling pathway and inhibitors of RAF could be of use for the treatment of various cancer types. We have designed potent RAF-1 inhibitors bearing novel bicyclic heterocycles as key structural elements for the interaction with the hinge region. In both series exploration of the SAR was focussed on the substitution of the phenyl ring, which binds to the induced fit pocket. Overall, it was confirmed that incorporation of lipophilic substituents was needed for potent Raf inhibition and a number of potent analogues were obtained.
Asunto(s)
Bencimidazoles/química , Isoquinolinas/química , Inhibidores de Proteínas Quinasas/síntesis química , Quinasas raf/antagonistas & inhibidores , Bencimidazoles/síntesis química , Bencimidazoles/farmacología , Sitios de Unión , Dominio Catalítico , Simulación por Computador , Diseño de Fármacos , Isoquinolinas/síntesis química , Isoquinolinas/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal , Relación Estructura-Actividad , Quinasas raf/metabolismoRESUMEN
Here we describe the discovery and optimization of hexahydro-2H-pyrano[3,2-c]quinolines (HHPQs) as potent and selective inhibitors of the mitotic kinesin-5 originally found during a high-throughput screening (HTS) campaign sampling our in-house compound collection. The compounds optimized subsequently and characterized herein were potently inhibiting the ATPase activity of Kinesin-5 and also exhibited consistent cellular activity, in that cells arrested in mitosis and apoptosis induction could be observed. X-ray crystallographic data demonstrated that these inhibitors bind in an allosteric pocket of Kinesin-5 distant from the nucleotide and microtubule binding sites. The selected clinical candidate EMD 534085 caused strong growth inhibition in human tumor xenograft models using Colo 205 colon carcinoma cells at doses below 30mg/kg administered twice weekly without showing severe toxicity as determined by loss of body weight.
Asunto(s)
Antineoplásicos/química , Inhibidores Enzimáticos/química , Cinesinas/antagonistas & inhibidores , Mitosis , Quinolinas/química , Regulación Alostérica , Animales , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Sitios de Unión , Línea Celular Tumoral , Cristalografía por Rayos X , Descubrimiento de Drogas , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Ensayos Analíticos de Alto Rendimiento , Humanos , Cinesinas/metabolismo , Ratones , Quinolinas/síntesis química , Quinolinas/farmacología , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Physical and chemical DNA-damaging agents are used widely in the treatment of cancer. Double-strand break (DSB) lesions in DNA are the most deleterious form of damage and, if left unrepaired, can effectively kill cancer cells. DNA-dependent protein kinase (DNA-PK) is a critical component of nonhomologous end joining (NHEJ), one of the two major pathways for DSB repair. Although DNA-PK has been considered an attractive target for cancer therapy, the development of pharmacologic DNA-PK inhibitors for clinical use has been lagging. Here, we report the discovery and characterization of a potent, selective, and orally bioavailable DNA-PK inhibitor, M3814 (peposertib), and provide in vivo proof of principle for DNA-PK inhibition as a novel approach to combination radiotherapy. M3814 potently inhibits DNA-PK catalytic activity and sensitizes multiple cancer cell lines to ionizing radiation (IR) and DSB-inducing agents. Inhibition of DNA-PK autophosphorylation in cancer cells or xenograft tumors led to an increased number of persistent DSBs. Oral administration of M3814 to two xenograft models of human cancer, using a clinically established 6-week fractionated radiation schedule, strongly potentiated the antitumor activity of IR and led to complete tumor regression at nontoxic doses. Our results strongly support DNA-PK inhibition as a novel approach for the combination radiotherapy of cancer. M3814 is currently under investigation in combination with radiotherapy in clinical trials.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Proteína Quinasa Activada por ADN/antagonistas & inhibidores , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias de Cabeza y Cuello/radioterapia , Inhibidores de Proteínas Quinasas/farmacología , Piridazinas/farmacología , Quinazolinas/farmacología , Radiación Ionizante , Animales , Apoptosis , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Proliferación Celular , Femenino , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/patología , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Ratones , Ratones Desnudos , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/radioterapia , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
PURPOSE: The epidermal growth factor receptor ErbB-1 is commonly expressed in pancreatic cancer and ErbB-1 targeting has shown promising results. We wanted to evaluate matuzumab (EMD72000), a fully humanized ErbB-1-specific monoclonal antibody in combination with gemcitabine in experimental pancreatic cancer. EXPERIMENTAL DESIGN: Using the human pancreatic cancer cell line L3.6pl, we investigated matuzumab in vitro and in vivo. ErbB-1 phosphorylation and downstream pathway activation were evaluated by Western blot. Proliferation and migration assays and fluorescence-activated cell sorting analysis were done. For in vivo studies, we used an orthotopic nude mice model in which 40 mg/kg of matuzumab+/-100 mg/kg of gemcitabine were administered twice weekly. Different treatment durations (7, 14, 21, and 25 days) and varying time points of treatment initiation (days 8, 15, 22, and 29) were evaluated. Ki67, CD31, and phosphorylated p44/42 mitogen-activated protein kinase (MAPK) immunohistochemistry were done. RESULTS: ErbB-1 phosphorylation and downstream MAPK and AKT signaling were significantly reduced by matuzumab. Matuzumab significantly inhibited proliferation and migration in vitro, and induced tumor cell apoptosis in a dose-dependant manner. Matuzumab therapy significantly lowered tumor volume in vivo, reduced lymph node and liver metastases, and decreased microvessel density and tumor cell proliferation. These effects were significantly enhanced when gemcitabine was added. A significant and prolonged antitumor activity was even evident with short-term therapy (7 days) and with a late onset of therapy (day 22 after tumor cell injection). CONCLUSIONS: Matuzumab is an effective agent with long-lasting antiproliferative, proapoptotic, antiangiogenic, and antimetastatic activity in human pancreatic cancer models. These effects might be potentiated by gemcitabine.
Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamiento farmacológico , Animales , Anticuerpos Monoclonales Humanizados , Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Desoxicitidina/administración & dosificación , Humanos , Ratones , Metástasis de la Neoplasia/prevención & control , Neovascularización Patológica/tratamiento farmacológico , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto , GemcitabinaRESUMEN
Kinesin-5 inhibitors (K5I) are promising antimitotic cancer drug candidates. They cause prolonged mitotic arrest and death of cancer cells, but their full range of phenotypic effects in different cell types has been unclear. Using time-lapse microscopy of cancer and normal cell lines, we find that a novel K5I causes several different cancer and noncancer cell types to undergo prolonged arrest in monopolar mitosis. Subsequent events, however, differed greatly between cell types. Normal diploid cells mostly slipped from mitosis and arrested in tetraploid G(1), with little cell death. Several cancer cell lines died either during mitotic arrest or following slippage. Contrary to prevailing views, mitotic slippage was not required for death, and the duration of mitotic arrest correlated poorly with the probability of death in most cell lines. We also assayed drug reversibility and long-term responses after transient drug exposure in MCF7 breast cancer cells. Although many cells divided after drug washout during mitosis, this treatment resulted in lower survival compared with washout after spontaneous slippage likely due to chromosome segregation errors in the cells that divided. Our analysis shows that K5Is cause cancer-selective cell killing, provides important kinetic information for understanding clinical responses, and elucidates mechanisms of drug sensitivity versus resistance at the level of phenotype.
Asunto(s)
Antimitóticos/uso terapéutico , Cinesinas/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Fenotipo , Antimitóticos/farmacología , Línea Celular Tumoral , Proliferación Celular , Segregación Cromosómica , Humanos , Interpretación de Imagen Asistida por Computador , Microscopía Fluorescente , Mitosis , Neoplasias/metabolismoRESUMEN
Combination therapies are widely accepted as a cornerstone for treatment of different cancer types. A tumor growth inhibition (TGI) model is developed for combinations of cetuximab and cisplatin obtained from xenograft mice. Unlike traditional TGI models, both natural cell growth and cell death are considered explicitly. The growth rate was estimated to 0.006 h-1 and the natural cell death to 0.0039 h-1 resulting in a tumor doubling time of 14 days. The tumor static concentrations (TSC) are predicted for each individual compound. When the compounds are given as single-agents, the required concentrations were computed to be 506 µg · mL-1 and 56 ng · mL-1 for cetuximab and cisplatin, respectively. A TSC curve is constructed for different combinations of the two drugs, which separates concentration combinations into regions of tumor shrinkage and tumor growth. The more concave the TSC curve is, the lower is the total exposure to test compounds necessary to achieve tumor regression. The TSC curve for cetuximab and cisplatin showed weak concavity. TSC values and TSC curves were estimated that predict tumor regression for 95% of the population by taking between-subject variability into account. The TSC concept is further discussed for different concentration-effect relationships and for combinations of three or more compounds.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Modelos Biológicos , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/patología , Cetuximab/administración & dosificación , Cisplatino/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto/métodosRESUMEN
PURPOSE: To explore in a panel of patient-derived xenograft models of human non-small cell lung cancer (NSCLC) whether high EGFR expression, was associated with cetuximab activity. EXPERIMENTAL DESIGN: NSCLC patient-derived xenograft models (n=45) were implanted subcutaneously into panels of nude mice and randomization cohorts were treated with either cetuximab, cisplatin, cisplatin plus cetuximab, vehicle control, or else were left untreated. Responses according to treatment were assessed at week 3 by analyzing the relative change in tumor volume and an experimental analogue of the Response Evaluation Criteria in Solid Tumors (RECIST) guidelines. An EGFR IHC score was calculated for each patient-derived xenograft model and response was assessed according to EGFR expression level. RESULTS: When tumors were stratified into high and low EGFR expression groups (IHC score threshold 200; scale 0-300), a stronger antitumor activity was seen in the high EGFR expression group compared with the low EGFR expression group in both the cetuximab monotherapy and cisplatin plus cetuximab combination therapy settings. For tumors treated with cisplatin plus cetuximab, the objective response rate was significantly higher in the high EGFR expression group compared with the low EGFR expression group (68% vs. 29%). Objective response rates were similar in high and low expression groups for tumors treated with cisplatin alone (27% vs. 24%, respectively). CONCLUSION: Cetuximab activity in NSCLC patient-derived xenograft models was demonstrated clearly only in tumors that expressed high levels of EGFR, as defined by an IHC score of ≥200.
Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Receptores ErbB/biosíntesis , Animales , Anticuerpos Monoclonales Humanizados/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Cetuximab , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Ratones , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The pleiotropic growth factor TGFbeta plays an important role in regulating responses to skin injury. TGFbeta targets many different cell types and is involved in all aspects of wound healing entailing inflammation, re-epithelialization, matrix formation and remodeling. To elucidate the role of TGFbeta signal transduction in keratinocytes during cutaneous wound healing, we have used transgenic mice expressing a dominant negative type II TGFbeta receptor exclusively in keratinocytes. We could demonstrate that this loss of TGFbeta signaling in keratinocytes led to an accelerated re-epithelialization of full thickness excisional wounds accompanied by an increased proliferation in keratinocytes at the wound edge. Furthermore, we show that impaired TGFbeta signaling in keratinocytes reduces apoptosis in re-epithelialized wounds of transgenic animals. A cDNA array identified the transcription factor early growth response factor 1 (Egr1) as a target gene for TGFbeta in late phases of the wound healing process. As a member of the immediate-early gene family, Egr1 is upregulated shortly after injury and induces the expression of growth factor genes. We could demonstrate that Egr1 expression is also upregulated in skin wounds which have already undergone re-epithelialization. In conclusion, we attribute the enhanced re-epithelialization in our transgenics to the resistance of keratinocytes to TGFbeta-mediated growth restriction and apoptosis induction. We also propose a new role for TGFbeta induced Egr1 in late phase wound repair.