RESUMO
With 54 new drugs and seven cellular and gene therapy products, the approvals by the US Food and Drug Administration (FDA) recovered 2023 from the 2022 dent back to the levels of 2020-2021. As in previous years of this annual review, we assign these new drugs to one of three levels of innovation: first drug against a condition ("first-in-indication"), first drug using a novel molecular mechanism ("first-in-class"), and "next-in-class," i.e., a drug using an already exploited molecular mechanism. We identify four (7%) "first-in-indication," 22 (36%) "first-in-class," and 35 (57%) "next-in-class" drugs. By treatment area, rare diseases (54%) and cancer drugs (23%) were once again the most prevalent (and partly overlapping) therapeutic areas. Other continuing trends were the use of accelerated regulatory approval pathways and the reliance on biopharmaceuticals (biologics). 2023 marks the approval of a first therapy based on CRISPR/Cas9 gene editing.
Assuntos
Aprovação de Drogas , United States Food and Drug Administration , Estados Unidos , Humanos , AnimaisRESUMO
Unlike genomic alterations, gene expression profiles have not been widely used to refine cancer therapies. We analyzed transcriptional changes in acute myeloid leukemia (AML) cell lines in response to standard first-line AML drugs cytarabine and daunorubicin by means of RNA sequencing. Those changes were highly cell- and treatment-specific. By comparing the changes unique to treatment-sensitive and treatment-resistant AML cells, we enriched for treatment-relevant genes. Those genes were associated with drug response-specific pathways, including calcium ion-dependent exocytosis and chromatin remodeling. Pharmacological mimicking of those changes using EGFR and MEK inhibitors enhanced the response to daunorubicin with minimum standalone cytotoxicity. The synergistic response was observed even in the cell lines beyond those used for the discovery, including a primary AML sample. Additionally, publicly available cytotoxicity data confirmed the synergistic effect of EGFR inhibitors in combination with daunorubicin in all 60 investigated cancer cell lines. In conclusion, we demonstrate the utility of treatment-evoked gene expression changes to formulate rational drug combinations. This approach could improve the standard AML therapy, especially in older patients.
Assuntos
Leucemia Mieloide Aguda , Humanos , Idoso , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Daunorrubicina/farmacologia , Linhagem Celular , Montagem e Desmontagem da Cromatina , Receptores ErbBRESUMO
While new drug approvals by the U.S. Food and Drug Administration (FDA) had remained stable or even increased in the first 2 years of the COVID-19 pandemic, the 37 newly approved drugs in 2022 are considerably less than the 53 and 50 new drugs approved in 2020 and 2021, respectively, and less than the rolling 10-year average of 43. As in previous years of this annual review, we assign these new drugs to one of three levels of innovation: first drug against a condition ("first-in-indication"), first drug using a novel molecular mechanism ("first-in-class"), and "next-in-class," i.e., a drug using an already exploited molecular mechanism. We identify two "first-in-indication" (ganaxolon and teplizumab), 20 (54%) "first-in-class," and 17 (46%) "next-in-class" drugs. By treatment area, rare diseases and cancer drugs were once again the most prevalent (partly overlapping) therapeutic areas. Other continuing trends were the use of accelerated regulatory approval pathways and the reliance on biopharmaceuticals (biologics).
Assuntos
Produtos Biológicos , COVID-19 , Estados Unidos , Humanos , United States Food and Drug Administration , Pandemias , Preparações Farmacêuticas , Aprovação de DrogasRESUMO
The second year of the COVID-19 pandemic had no adverse effect on the number of new drug approvals by the US Food and Drug Administration (FDA). Quite the contrary, with a total of 50 new drugs, 2021 belongs to the most successful FDA years. We assign these new drugs to one of three levels of innovation: (1) first drug against a condition ("first-in-indication"), (2) first drug using a novel molecular mechanism ("first-in-class"), and (3) "next-in-class", i.e., a drug using an already exploited molecular mechanism. We identify 21 first-in-class, 28 next-in-class, and only one first-in-indication drugs. By treatment area, the largest group is once again cancer drugs, many of which target specific genetic alterations. Every second drug approved in 2021 targets an orphan disease, half of them being cancers. Small molecules continue to dominate new drug approvals, followed by antibodies and non-antibody biopharmaceuticals. In 2021, the FDA continued to approve drugs without strong evidence of clinical effects, best exemplified by the aducanumab controversy.
Assuntos
Tratamento Farmacológico da COVID-19 , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Aprovação de Drogas , Humanos , Pandemias , Estados Unidos , United States Food and Drug AdministrationRESUMO
Cancer therapies with anthracyclines have been shown to induce cardiovascular complications. The aims of this study were to establish an in vitro induced pluripotent stem cell model (iPSC) of anthracycline-induced cardiotoxicity (ACT) from patients with an aggressive form of B-cell lymphoma and to examine whether doxorubicin (DOX)-treated ACT-iPSC cardiomyocytes (CM) can recapitulate the clinical features exhibited by patients, and thus help uncover a DOX-dependent pathomechanism. ACT-iPSC CM generated from individuals with CD20+ B-cell lymphoma who had received high doses of DOX and suffered cardiac dysfunction were studied and compared to control-iPSC CM from cancer survivors without cardiac symptoms. In cellular studies, ACT-iPSC CM were persistently more susceptible to DOX toxicity including augmented disorganized myofilament structure, changed mitochondrial shape, and increased apoptotic events. Consistently, ACT-iPSC CM and cardiac fibroblasts isolated from fibrotic human ACT myocardium exhibited higher DOX-dependent reactive oxygen species. In functional studies, Ca2+ transient amplitude of ACT-iPSC CM was reduced compared to control cells, and diastolic sarcoplasmic reticulum Ca2+ leak was DOX-dependently increased. This could be explained by overactive CaMKIIδ in ACT CM. Together with DOX-dependent augmented proarrhythmic cellular triggers and prolonged action potentials in ACT CM, this suggests a cellular link to arrhythmogenic events and contractile dysfunction especially found in ACT engineered human myocardium. CamKIIδ inhibition prevented proarrhythmic triggers in ACT. In contrast, control CM upregulated SERCA2a expression in a DOX-dependent manner, possibly to avoid heart failure conditions. In conclusion, we developed the first human patient-specific stem cell model of DOX-induced cardiac dysfunction from patients with B-cell lymphoma. Our results suggest that DOX-induced stress resulted in arrhythmogenic events associated with contractile dysfunction and finally in heart failure after persistent stress activation in ACT patients.
Assuntos
Cardiopatias , Insuficiência Cardíaca , Células-Tronco Pluripotentes Induzidas , Linfoma de Células B , Neoplasias , Cardiotoxicidade/metabolismo , Cardiotoxicidade/patologia , Doxorrubicina/metabolismo , Doxorrubicina/toxicidade , Cardiopatias/metabolismo , Insuficiência Cardíaca/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Miócitos Cardíacos/metabolismo , Neoplasias/metabolismoRESUMO
Recently approved cancer drugs remain out-of-reach to most patients due to prohibitive costs and only few produce clinically meaningful benefits. An untapped alternative is to enhance the efficacy and safety of existing cancer drugs. We hypothesized that the response to topoisomerase II poisons, a very successful group of cancer drugs, can be improved by considering treatment-associated transcript levels. To this end, we analyzed transcriptomes from Acute Myeloid Leukemia (AML) cell lines treated with the topoisomerase II poison etoposide. Using complementary criteria of co-regulation within networks and of essentiality for cell survival, we identified and functionally confirmed 11 druggable drivers of etoposide cytotoxicity. Drivers with pre-treatment expression predicting etoposide response (e.g., PARP9) generally synergized with etoposide. Drivers repressed by etoposide (e.g., PLK1) displayed standalone cytotoxicity. Drivers, whose modulation evoked etoposide-like gene expression changes (e.g., mTOR), were cytotoxic both alone and in combination with etoposide. In summary, both pre-treatment gene expression and treatment-driven changes contribute to the cell killing effect of etoposide. Such targets can be tweaked to enhance the efficacy of etoposide. This strategy can be used to identify combination partners or even replacements for other classical anticancer drugs, especially those interfering with DNA integrity and transcription.
RESUMO
AIM: To identify gene variants responsible for anthracycline-induced cardiotoxicity. PATIENTS & METHODS: Polymorphisms of the NADPH oxidase subunits and of the anthracycline transporters ABCC1, ABCC2 and SLC28A3 were genotyped in elderly patients (61-80 years) treated for aggressive CD20(+) B-cell lymphomas with CHOP-14 with or without rituximab and followed up for 3 years. RESULTS: The accumulation of RAC2 subunit genotypes TA/AA among cases was statistically significant upon adjustment for gender, age and doxorubicin dose in a multivariate logistic regression analysis (OR: 2.3, p = 0.028; univariate: OR: 1.8, p = 0.077). RAC2 and CYBA genotypes were significantly associated with anthracycline-induced cardiotoxicity in a meta-analysis of this and a similar previous study. CONCLUSION: Our results support the theory that NADPH oxidase is involved in anthracycline-induced cardiotoxicity. Original submitted 9 July 2014; Revision submitted 19 December 2014.
Assuntos
Cardiotoxicidade/genética , Linfoma de Células B/tratamento farmacológico , NADPH Oxidases/genética , Proteínas rac de Ligação ao GTP/genética , Idoso , Idoso de 80 Anos ou mais , Antraciclinas/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cardiotoxicidade/patologia , Ciclofosfamida/efeitos adversos , Doxorrubicina/efeitos adversos , Feminino , Estudos de Associação Genética , Humanos , Linfoma de Células B/genética , Masculino , Pessoa de Meia-Idade , Proteína 2 Associada à Farmacorresistência Múltipla , Polimorfismo de Nucleotídeo Único , Prednisona/efeitos adversos , Rituximab/efeitos adversos , Vincristina/efeitos adversos , Proteína RAC2 de Ligação ao GTPRESUMO
BACKGROUND AND PURPOSE: The catalytic topoisomerase II inhibitor dexrazoxane has been associated not only with improved cancer patient survival but also with secondary malignancies and reduced tumour response. EXPERIMENTAL APPROACH: We investigated the DNA damage response and the role of the activating transcription factor 3 (ATF3) accumulation in tumour cells exposed to dexrazoxane. KEY RESULTS: Dexrazoxane exposure induced topoisomerase IIα (TOP2A)-dependent cell death, γ-H2AX accumulation and increased tail moment in neutral comet assays. Dexrazoxane induced DNA damage responses, shown by enhanced levels of γ-H2AX/53BP1 foci, ATM (ataxia telangiectasia mutated), ATR (ATM and Rad3-related), Chk1 and Chk2 phosphorylation, and by p53 accumulation. Dexrazoxane-induced γ-H2AX accumulation was dependent on ATM. ATF3 protein was induced by dexrazoxane in a concentration- and time-dependent manner, which was abolished in TOP2A-depleted cells and in cells pre-incubated with ATM inhibitor. Knockdown of ATF3 gene expression by siRNA triggered apoptosis in control cells and diminished the p53 protein level in both control and dexrazoxane -treated cells. This was accompanied by increased γ-H2AX accumulation. ATF3 knockdown also delayed the repair of dexrazoxane -induced DNA double-strand breaks. CONCLUSIONS AND IMPLICATIONS: As with other TOP2A poisons, dexrazoxane induced DNA double-strand breaks followed by activation of the DNA damage response. The DNA damage-triggered ATF3 controlled p53 accumulation and generation of double-strand breaks and is proposed to serve as a switch between DNA damage and cell death following dexrazoxane treatment. These findings suggest a mechanistic explanation for the diverse clinical observations associated with dexrazoxane.
Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/antagonistas & inibidores , Dexrazoxano/farmacologia , Fibrossarcoma/tratamento farmacológico , Inibidores da Topoisomerase II/farmacologia , Fator 3 Ativador da Transcrição/genética , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Apoptose/efeitos dos fármacos , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , DNA Topoisomerases Tipo II/genética , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Fibrossarcoma/genética , Fibrossarcoma/metabolismo , Fibrossarcoma/patologia , Histonas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Proteína Supressora de Tumor p53/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53RESUMO
BACKGROUND: The bisdioxopiperazine dexrazoxane (DRZ) prevents anthracycline-induced heart failure, but its clinical use is limited by uncertain cardioprotective mechanism and by concerns of interference with cancer response to anthracyclines and of long-term safety. METHODS: We investigated the effects of DRZ on the stability of topoisomerases IIα (TOP2A) and IIß (TOP2B) and on the DNA damage generated by poisoning these enzymes by the anthracycline doxorubicin (DOX). RESULTS: DRZ given i.p. transiently depleted in mice the predominant cardiac isoform Top2b. The depletion was also seen in H9C2 cardiomyocytes and it was attenuated by mutating the bisdioxopiperazine binding site of TOP2B. Consistently, the accumulation of DOX-induced DNA double strand breaks (DSB) by wild-type, although not by mutant TOP2B, was reduced by DRZ. In contrast, the DRZ analogue ICRF-161, which is capable of iron chelation but not of TOP2B binding and cardiac protection, did not deplete TOP2B and did not prevent the accumulation of DOX-induced DSB. TOP2A, re-expressed in cultured cardiomyocytes by fresh serum, was depleted by DRZ along with TOP2B. DRZ depleted TOP2A also from fibrosarcoma-derived cells, but not from lung cancer-derived and human embryo-derived cells. DRZ-mediated TOP2A depletion reduced the accumulation of DOX-induced DSB. CONCLUSIONS: Taken together, our data support a model of anthracycline-induced heart failure caused by TOP2B-mediated DSB and of its prevention by DRZ via TOP2B degradation rather than via iron chelation. The depletion of TOP2B and TOP2A suggests an explanation for the reported DRZ interference with cancer response to anthracyclines and for DRZ side-effects.
Assuntos
Antineoplásicos/farmacologia , Dano ao DNA/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , Dexrazoxano/farmacologia , Doxorrubicina/toxicidade , Inibidores da Topoisomerase II/farmacologia , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , DNA Topoisomerases Tipo II/química , DNA Topoisomerases Tipo II/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Coração/efeitos dos fármacos , Humanos , Isoenzimas , Camundongos , Mutação , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose , Substâncias Protetoras/farmacologia , Domínios e Motivos de Interação entre Proteínas/genéticaRESUMO
Cardio-oncology is a relatively new discipline that focuses on the cardiovascular sequelae of anti-tumour drugs. As any other young adolescent discipline, cardio-oncology struggles to define its scientific boundaries and to identify best standards of care for cancer patients or survivors at risk of cardiovascular events. The International Colloquium on Cardio-Oncology was held in Rome, Italy, 12-14 March 2014, with the aim of illuminating controversial issues and unmet needs in modern cardio-oncology. This colloquium embraced contributions from different kind of disciplines (oncology and cardiology but also paediatrics, geriatrics, genetics, and translational research); in fact, cardio-oncology goes way beyond the merging of cardiology with oncology. Moreover, the colloquium programme did not review cardiovascular toxicity from one drug or the other, rather it looked at patients as we see them in their fight against cancer and eventually returning to everyday life. This represents the melting pot in which anti-cancer therapies, genetic backgrounds, and risk factors conspire in producing cardiovascular sequelae, and this calls for screening programmes and well-designed platforms of collaboration between one key professional figure and another. The International Colloquium on Cardio-Oncology was promoted by the Menarini International Foundation and co-chaired by Giorgio Minotti (Rome), Joseph R Carver (Philadelphia, Pennsylvania, United States), and Steven E Lipshultz (Detroit, Michigan, United States). The programme was split into five sessions of broad investigational and clinical relevance (what is cardiotoxicity?, cardiotoxicity in children, adolescents, and young adults, cardiotoxicity in adults, cardiotoxicity in special populations, and the future of cardio-oncology). Here, the colloquium chairs and all the session chairs briefly summarised what was said at the colloquium. Topics and controversies were reported on behalf of all members of the working group of the International Colloquium on Cardio-Oncology.
RESUMO
OBJECTIVES: The reduction in mother-to-child transmission of HIV-1 by single-dose nevirapine given at birth onset is achieved at the expense of de novo HIV-1 resistance mutations. In the VITA1 study, single-dose carbamazepine accelerated nevirapine elimination, but the accompanying trend towards fewer de novo HIV-1 mutations was statistically non-significant. METHODS: We investigated if the effect of carbamazepine was confounded by the individual variability in nevirapine metabolism and transport. RESULTS: Nine of 34 (26%) single-dose nevirapine-treated women had one or more nevirapine-associated resistance mutations, compared with 3 of 34 (9%) in the single-dose nevirapine/carbamazepine arm. The genetic polymorphisms in CYP2B6 and MRP7 affected neither nevirapine kinetics nor the development of HIV-1 resistance. In contrast, the reduction in HIV-1 mutations by single-dose carbamazepine reached statistical significance at Pâ=â0.04 with an OR of 0.1 (95% CI 0.01-0.90) upon consideration of CYP3A activity, defined as the ratio of 4ß-hydroxycholesterol to cholesterol, and it was more likely in women with higher CYP3A activity. These findings were in agreement with CYP3A induction in carbamazepine-treated patients. Likewise, carbamazepine induced CYP3A4, but not CYP2B6, in vitro when combined with nevirapine. CONCLUSIONS: The induction of nevirapine elimination reduces HIV-1 resistance mutations, but this effect is modulated by individual CYP3A activity. The study suggests that CYP3A4 activity could be monitored using an endogenous marker and, if needed, boosted to improve clinical endpoints.
Assuntos
Fármacos Anti-HIV/administração & dosagem , Carbamazepina/administração & dosagem , Indutores do Citocromo P-450 CYP3A/administração & dosagem , Farmacorresistência Viral , HIV-1/efeitos dos fármacos , Mutação de Sentido Incorreto/efeitos dos fármacos , Nevirapina/administração & dosagem , Fármacos Anti-HIV/farmacologia , Carbamazepina/metabolismo , Quimioprevenção/métodos , Citocromo P-450 CYP3A/metabolismo , Indutores do Citocromo P-450 CYP3A/metabolismo , Feminino , Infecções por HIV/prevenção & controle , HIV-1/genética , Humanos , Nevirapina/farmacologia , Gravidez , Resultado do TratamentoRESUMO
BACKGROUND & AIMS: A fraction of gastrointestinal stromal tumor (GIST) cells overexpress the platelet-derived growth factor receptor (PDGFR)A, although most overexpress KIT. It is not known if this is because these receptor tyrosine kinases have complementary oncogenic potential, or because of heterogeneity in the cellular origin of GIST. Little also is known about why Hedgehog (HH) signaling is activated in some GIST. HH binds to and inactivates the receptor protein patched homolog (PTCH). METHODS: Ptch was conditionally inactivated in mice (to achieve constitutive HH signaling) using a Cre recombinase regulated by the lysozyme M promoter. Cre-expressing cells were traced using R26R-LacZ reporter mice. Tumors were characterized by in situ hybridization, immunohistochemistry, immunoblot, and quantitative reverse-transcriptase polymerase chain reaction analyses. Cell transformation was assessed by soft agar assay. RESULTS: Loss of Ptch from lysozyme M-expressing cells resulted in the development of tumors of GIST-like localization and histology; these were reduced when mice were given imatinib, a drug that targets KIT and PDGFRA. The Hh signaling pathway was activated in the tumor cells, and Pdgfrα, but not Kit, was overexpressed and activated. Lineage tracing revealed that Cre-expressing intestinal cells were Kit-negative. These cells sometimes expressed Pdgfrα and were located near Kit-positive interstitial cells of Cajal. In contrast to KIT, activation of PDGFRA increased anchorage-independent proliferation and was required for tumor formation in mice by cells with activated HH signaling. CONCLUSIONS: Inactivation of Ptch in mice leads to formation of GIST-like tumors that express Pdgfrα, but not Kit. Activation of Pdgfrα signaling appears to facilitate tumorigenesis.
Assuntos
Neoplasias Gastrointestinais/genética , Tumores do Estroma Gastrointestinal/metabolismo , Proteínas Hedgehog/genética , Leiomiossarcoma/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Superfície Celular/genética , Animais , Benzamidas , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/metabolismo , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Expressão Gênica , Genótipo , Proteínas Hedgehog/metabolismo , Humanos , Mesilato de Imatinib , Integrases/genética , Integrases/metabolismo , Mucosa Intestinal/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Leiomiossarcoma/metabolismo , Camundongos , Muramidase/genética , Muramidase/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores Patched , Receptor Patched-1 , Piperazinas/uso terapêutico , Regiões Promotoras Genéticas , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Receptores de Superfície Celular/metabolismo , Transdução de Sinais/genética , Proteína GLI1 em Dedos de Zinco , Proteína Gli2 com Dedos de Zinco , Proteína Gli3 com Dedos de ZincoRESUMO
The multidrug resistance-associated protein 2 (MRP2/ABCC2) is involved in the efflux of endogenous and xenobiotic substrates, including several anticancer and antiviral drugs. The functional consequences of ABCC2 protein variants remain inconsistent, which may be due to shortcomings of the in vitro assays used. To study systematically the functional consequences of nonsynonymous ABCC2 variants, we used a novel "Screen and Insert" (ScIn) technology to achieve stable and highly reproducible expression of 13 ABCC2 variants in HT1080 cells. Western blotting revealed lower (30-65%) ABCC2 expression for D333G, R1174H, and R1181L as compared with wild type (WT; 100%), whereas the linked variant V1188E/C1515Y resulted in higher expression (150%). R1174H caused mislocalization of ABCC2 to the cytoplasm with an endoplasmic reticulum-like distribution. Variants N1244K and R1174H decreased transport of glutathione-methylfluorescein (GS-MF) and glutathione-monochlorobimane (GS-MCB) by 80% and 50%, respectively, whereas R1181L and P1291L reduced only GS-MCB transport by 50% as compared with WT. Contrary to protein data, the double variant V1188E/C1515Y decreased specific transport activity for GS-MF and GS-MCB by 40%. The ScIn approach is a feasible and reliable method to functionally characterize systematically ABCC2 variants. D333G, R1174H, R1181L, N1244K, P1291L, and double variant V1188E/C1515Y have been identified as most promising for further clinical evaluation.
Assuntos
Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Negro ou Afro-Americano/genética , Asiático/genética , Linhagem Celular Tumoral , Cloraminas/metabolismo , Fibrossarcoma/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Variação Genética , Células HEK293 , Haplótipos , Humanos , Proteína 2 Associada à Farmacorresistência Múltipla , Mutação de Sentido Incorreto , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tetraciclina/farmacologiaRESUMO
We searched for a drug capable of sensitization of sarcoma cells to doxorubicin (DOX). We report that the dual PI3K/mTOR inhibitor PI103 enhances the efficacy of DOX in several sarcoma cell lines and interacts with DOX in the induction of apoptosis. PI103 decreased the expression of MDR1 and MRP1, which resulted in DOX accumulation. However, the enhancement of DOX-induced apoptosis was unrelated to DOX accumulation. Neither did it involve inhibition of mTOR. Instead, the combination treatment of DOX plus PI103 activated Bax, the mitochondrial apoptosis pathway, and caspase 3. Caspase 3 activation was also observed in xenografts of sarcoma cells in nude mice upon combination of DOX with the specific PI3K inhibitor GDC-0941. Although the increase in apoptosis did not further impact on tumor growth when compared to the efficient growth inhibition by GDC-0941 alone, these findings suggest that inhibition of PI3K may improve DOX-induced proapoptotic effects in sarcoma. Taken together with similar recent studies of neuroblastoma- and glioblastoma-derived cells, PI3K inhibition seems to be a more general option to sensitize tumor cells to anthracyclines.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase , Sarcoma/tratamento farmacológico , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Caspase 3/metabolismo , Linhagem Celular Tumoral , Citocromos c/metabolismo , Doxorrubicina/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Ativação Enzimática/efeitos dos fármacos , Furanos/administração & dosagem , Expressão Gênica/efeitos dos fármacos , Humanos , Indazóis/administração & dosagem , Camundongos , Camundongos Nus , Proteínas Associadas à Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Piridinas/administração & dosagem , Pirimidinas/administração & dosagem , Sarcoma/enzimologia , Sulfonamidas/administração & dosagem , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/metabolismoRESUMO
NAD(P)H oxidase is a major endogenous source of reactive oxygen species (ROS). ROS may not only be involved in carcinogenesis but also in efficacy of chemotherapeutic agents like doxorubicin. By a comprehensive genotyping approach covering 48 genetic polymorphisms (single-nucleotide polymorphisms) in five subunits of phagocytic NAD(P)H oxidase, we asked whether they affect gene expression, enzymatic activity, and outcome of CHO(E)P chemotherapy. A highly consistent effect was observed for the CYBA 640A>G variant. In peripheral blood granulocytes of 125 healthy volunteers, the G allele of 640A>G was associated with lower NAD(P)H oxidase activity (P = 0.006). Moreover, the G allele was associated with lower mRNA and protein expression (both P = 0.02). Of clinical importance, the outcome of patients suffering from non-Hodgkin lymphoma and treated with CHO(E)P regimen was dependent on the CYBA 640A>G polymorphism. In an exploratory study (n = 401), carriers of 640GG had an event-free survival (EFS) risk ratio of 1.95 [95% confidence interval (95% CI), 1.31-2.90; P = 0.001] compared with 640AA. In a confirmatory set (n = 477), the risk ratios were 1.53 (1.04-2.25, P = 0.03). The complete set of 878 patients showed a relative risk of 1.72 (1.30-2.26) and 1.59 (1.14-2.21) for EFS and overall survival, respectively. Further molecular-biological experiments showed lower expression and reduced stability of transcripts with the G allele in lymphoblastoid cell lines. Transfection of allele-specific plasmids into HEK293 cells elicited lower activity for the G allele in a luciferase reporter gene construct. Thus, CYBA 640A>G was shown to be a functional polymorphism with possible consequences for patients receiving CHO(E)P chemotherapy and might have further implications for other ROS-mediated modalities.
Assuntos
Linfoma não Hodgkin/enzimologia , NADPH Oxidases/genética , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Expressão Gênica , Humanos , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/genética , Masculino , Pessoa de Meia-Idade , NADPH Oxidases/biossíntese , NADPH Oxidases/metabolismo , Polimorfismo de Nucleotídeo Único , Prednisolona/administração & dosagem , Subunidades Proteicas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Resultado do Tratamento , Vincristina/administração & dosagem , Adulto JovemRESUMO
Coadministration of the iron chelator dexrazoxane reduces by 80% the incidence of heart failure in cancer patients treated with anthracyclines. The clinical application of dexrazoxane is limited, however, because its ability to inhibit topoisomerase IIα (TOP2A) is feared to adversely affect anthracycline chemotherapy, which involves TOP2A-mediated generation of DNA double-strand breaks (DSB). Here, we investigated the apoptotic effects of dexrazoxane and the anthracycline doxorubicin, alone and in combination, in a tumor cell line with conditionally regulated expression of TOP2A. Each drug caused apoptosis that was only partly dependent on TOP2A. Unexpectedly, dexrazoxane was found to cause TOP2A depletion, thereby reducing the doxorubicin-induced accumulation of DSB. Despite this latter effect, dexrazoxane showed no adverse effect on doxorubicin-induced apoptosis. This could be explained by the TOP2A-independent apoptotic effects of each drug: those of doxorubicin included TOP2A-independent DSB formation and depletion of intracellular glutathione, whereas those of dexrazoxane were caspase independent. In conclusion, both doxorubicin and dexrazoxane induce apoptosis via TOP2A-dependent and TOP2A-independent mechanisms, the latter compensating for the reduction in cell killing due to dexrazoxane-induced TOP2A depletion. These observations suggest an explanation for the absence of adverse dexrazoxane effects on clinical responses to doxorubicin.
Assuntos
Antígenos de Neoplasias/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Doxorrubicina/farmacologia , Razoxano/farmacologia , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glutationa/análise , Histonas/metabolismo , Humanos , Proteínas de Ligação a Poli-ADP-Ribose , Proteína Supressora de Tumor p53/metabolismoRESUMO
Mutations in Patched (PTCH) have been associated with tumors characteristic both for children [medulloblastoma (MB) and rhabdomyosarcoma (RMS)] and for elderly [basal cell carcinoma (BCC)]. The determinants of the variability in tumor onset and histology are unknown. We investigated the effects of the time-point and dosage of Ptch inactivation on tumor spectrum using conditional Ptch-knockout mice. Ptch heterozygosity induced prenatally resulted in the formation of RMS, which was accompanied by the silencing of the remaining wild-type Ptch allele. In contrast, RMS was observed neither after mono- nor biallelic postnatal deletion of Ptch. Postnatal biallelic deletion of Ptch led to BCC precancerous lesions of the gastrointestinal epithelium and mesenteric tumors. Hamartomatous gastrointestinal cystic tumors were induced by monoallelic, but not biallelic Ptch mutations, independently of the time-point of mutation induction. These data suggest that the expressivity of Ptch deficiency is largely determined by the time-point, the gene dose and mode of Ptch inactivation. Furthermore, they point to key differences in the tumorigenic mechanisms underlying adult and childhood tumors. The latter ones are unique among all tumors since their occurrence decreases rather than increases with age. A better understanding of mechanisms underlying this ontological restriction is of potential therapeutic value.
Assuntos
Envelhecimento/patologia , Carcinoma Basocelular/genética , Dosagem de Genes , Inativação Gênica , Receptores de Superfície Celular/fisiologia , Rabdomiossarcoma/genética , Envelhecimento/genética , Animais , Carcinoma Basocelular/patologia , Cistos/genética , Cistos/patologia , Neoplasias Gastrointestinais/embriologia , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Mutação em Linhagem Germinativa , Camundongos , Camundongos Knockout , Neoplasias Musculares/genética , Neoplasias Musculares/patologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Mutação , Receptores Patched , Receptor Patched-1 , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Receptores de Superfície Celular/genética , Rabdomiossarcoma/embriologia , Rabdomiossarcoma/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologiaRESUMO
The roles of individual nitric oxide synthases (NOS) in anthracycline-related cardiotoxicity are not completely understood. We investigated the effects of a chronic treatment with doxorubicin (DOX) on knockouts of the individual NOS isozymes and on transgenic mice with myocardial overexpression of eNOS. Fractional shortening (FS) was reduced in untreated homozygous nNOS and iNOS knockouts as well as in eNOS transgenics. DOX-induced FS decrease in wild-type mice was attenuated only in eNOS knockouts, which were found to overexpress nNOS. No worsening of contractility was observed in DOX-treated eNOS transgenics and iNOS knockouts. Although the surviving DOX-treated nNOS knockouts exhibited no further impairment in contractility, most (70%) animals died within 7 weeks after treatment onset. In comparison to untreated wild-type hearts, the nitric oxide (NO) level was lower in hearts from DOX-treated wild-type mice and in all three untreated knockouts. DOX treatment had no effect on NO in the knockouts. These data indicate differential roles of the individual NOS in DOX-induced cardiotoxicity. Protection against DOX effects conferred by eNOS deletion may be mediated by a compensatory overexpression of nNOS. NOS inhibition-based prevention of anthracycline-induced cardiotoxicity should be eNOS-selective, simultaneously avoiding inhibiting nNOS.
Assuntos
Antibióticos Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , Cardiopatias/induzido quimicamente , Óxido Nítrico/metabolismo , Animais , Antibióticos Antineoplásicos/administração & dosagem , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Cardiopatias/mortalidade , Cardiopatias/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Contração Miocárdica/efeitos dos fármacos , Óxido Nítrico Sintase Tipo I/genética , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Taxa de SobrevidaRESUMO
Patched (Ptch) heterozygous mice develop medulloblastoma (MB) and rhabdomyosarcoma (RMS) resembling the corresponding human tumors. We have previously shown that epigenetic silencing of the intact Ptch allele contributes to tumor formation in this model. Here, we investigated whether targeting of epigenetic silencing mechanisms could be useful in the treatment of Ptch-associated cancers. A reduction of endogenous DNA methyltransferase1 (Dnmt1) activity significantly reduced tumor incidence in heterozygous Ptch knockout mice. A combined treatment with the Dnmt inhibitor 5-aza-2'deoxycytidine (5-aza-dC) and the histone deacetlyase (HDAC) inhibitor valproic acid (VPA) efficiently prevented MB and RMS formation, whereas monotherapies with either drug were less effective. Wild-type Ptch expression was efficiently reactivated in tumors by 5-aza-dC/VPA combination therapy. This was associated with reduced methylation of the Ptch promoter and induction of histone hyperacetylation suggesting inhibition of HDACs in vivo. However, the treatment was not effective in clinically overt, advanced stage tumors. This is a first in vivo demonstration that targeting of Dnmt and HDAC activities is highly effective in preventing formation of Ptch-associated tumors. The results suggest a novel clinical strategy for consolidation therapy of corresponding tumors in humans after completion of conventional treatment. Our data also suggest that epigenetic therapy may be less effective in treating advanced stages of tumors, at least in this tumor model.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Meduloblastoma/tratamento farmacológico , Receptores de Superfície Celular/genética , Rabdomiossarcoma/tratamento farmacológico , Acetilação , Animais , Azacitidina/administração & dosagem , Azacitidina/análogos & derivados , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Decitabina , Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Inibidores de Histona Desacetilases , Histona Desacetilases/metabolismo , Histonas/metabolismo , Meduloblastoma/genética , Meduloblastoma/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Receptores Patched , Receptor Patched-1 , Rabdomiossarcoma/genética , Rabdomiossarcoma/metabolismo , Ácido Valproico/administração & dosagemRESUMO
A first step in the enzymatic disposition of the antineoplastic drug doxorubicin (DOX) is the reduction to doxorubicinol (DOX-OL). Because DOX-OL is less antineoplastic but more cardiotoxic than the parent compound, the individual rate of this reaction may affect the antitumor effect and the risk of DOX-induced heart failure. Using purified enzymes and human tissues we determined enzymes generating DOX-OL and interindividual differences in their activities. Human tissues express at least two DOX-reducing enzymes. High-clearance organs (kidney, liver, and the gastrointestinal tract) express an enzyme with an apparent Km of approximately 140 microM. Of six enzymes found to reduce DOX, Km values in this range are exhibited by carbonyl reductase 1 (CBR1) and aldo-keto reductase (AKR) 1C3. CBR1 is expressed in these three organs at higher levels than AKR1C3, whereas AKR1C3 has higher catalytic efficiency. However, inhibition constants for DOX reduction with 4-amino-1-tert-butyl-3-(2-hydroxyphenyl)pyrazolo[3,4-d]pyrimidine (an inhibitor that can discriminate between CBR1 and AKR1C3) were identical for CBR1 and human liver cytosol, but not for AKR1C3. These results suggest that CBR1 is a predominant hepatic DOX reductase. In cytosols from 80 human livers, the expression level of CBR1 and the activity of DOX reduction varied >70- and 22-fold, respectively, but showed no association with CBR1 gene variants found in these samples. Instead, the interindividual differences in CBR1 expression and activity may be mediated by environmental factors acting via recently identified xenobiotic response elements in the CBR1 promoter. The variability in the CBR1 expression may affect outcomes of therapies with DOX, as well as with other CBR1 substrates.