RESUMEN
The in vivo Pig-a assay is being used in safety studies to evaluate the potential of chemicals to induce somatic cell gene mutations. Ongoing work is aimed at developing an Organisation for Economic Cooperation and Development (OECD) test guideline to support routine use for regulatory purposes (OECD project number 4.93). Among the details that will need to be articulated in an eventual guideline are recommended treatment and harvest schedules. With this in mind, experiments reported herein were performed with Wistar Han rats exposed to aristolochic acid I (AA), 1,3-propane sultone, chlorambucil, thiotepa or melphalan using each of two commonly used treatment schedules: 3 or 28 consecutive days. In the case of the 3-day studies, blood was collected for Pig-a analysis on days 15 or 16 and 29 or 30. For the 28-day studies blood was collected on day 29 or 30. The effect of treatment on mutant reticulocytes and mutant erythrocytes was evaluated with parametric pair-wise tests. While each of the five mutagens increased mutant phenotype cell frequencies irrespective of study design, statistical significance was consistently achieved at lower dose levels when the 28-day format was used (e.g. 2.75 vs 20 mg/kg/bw for AA). To more thoroughly investigate the dose-response relationships, benchmark dose (BMD) analyses were performed with PROAST software. These results corroborate the pair-wise testing results in that lower BMD values were obtained with the 28-day design. Finally, mutagenic potency, as measured by BMD analyses, most consistently correlated with the mutagens' tumorigenic dose 50 values when the lengthier treatment schedule was used. Collectively, these results suggest that both 3- and 28-day treatment schedules have merit in hazard identification-type studies. That being said, for the purpose of regulatory safety assessments, there are clear advantages to study designs that utilise protracted exposures.
Asunto(s)
Proteínas de la Membrana/genética , Pruebas de Mutagenicidad/métodos , Mutágenos/toxicidad , Mutación , Reticulocitos/efectos de los fármacos , Animales , Ácidos Aristolóquicos/toxicidad , Clorambucilo/toxicidad , Eritrocitos/efectos de los fármacos , Masculino , Melfalán/toxicidad , Ratas , Ratas Wistar , Tiofenos/toxicidad , Tiotepa/toxicidad , Factores de TiempoRESUMEN
The Pig-a assay, which uses reticulocytes (PIGRET assay) as target cells, is anticipated to detect mutagenicity at earlier time points than the RBC Pig-a assay, which uses all red blood cells as target cells. As part of a collaborative study conducted by the Mammalian Mutagenicity Study (MMS) Group, we evaluated the PIGRET and RBC Pig-a assays to detect Pig-a gene mutations induced by the carcinogen thiotepa. A single dose of thiotepa at 7.5, 15, and 30mg/kg was administered to 8-week-old male Sprague-Dawley rats by oral gavage. PIGRET and RBC Pig-a assays were performed using peripheral blood collected from rats 7, 14, and 28days after thiotepa administration (Day 0 as the day of administration), and the resulting Pig-a mutant frequencies (MFs) were compared. Increased Pig-a MF was observed from Day 7 onwards using the PIGRET assay. Pig-a MF remained fairly constant thereafter until Day 28 in the 30mg/kg group, whereas it peaked on Day 14 in the 7.5 and 15mg/kg groups. Using the RBC Pig-a assay, on the other hand, no significant increase in MF was observed at any of the dosages on Days 7, 14, or 28. These findings show that Pig-a gene mutations following a single dose of thiotepa were detected using the PIGRET assay but not the RBC Pig-a assay, which suggests that PIGRET assay is more suitable than RBC Pig-a assay for evaluating the in vivo mutagenicity by a single dose.
Asunto(s)
Eritrocitos/efectos de los fármacos , Proteínas de la Membrana/genética , Pruebas de Mutagenicidad/métodos , Mutágenos/toxicidad , Reticulocitos/efectos de los fármacos , Tiotepa/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
Validation of the Pig-a gene mutation assay has been based mainly on studies in male rodents. To determine if the mutagen-induced responses of the X-linked Pig-a gene differ in females compared to males, groups of five male and female Sprague Dawley rats were exposed to the mutagens 1,3-propane sultone (80mg/kg/day), ethyl carbamate (600mg/kg/day), or thiotepa (7.5mg/kg/day) for three consecutive days (study days 1-3). Pig-a mutant phenotype reticulocyte (RET(CD59-)) and mutant phenotype erythrocyte (RBC(CD59-)) frequencies were determined on study days -4, 15, 30 and 46 using immunomagnetic separation in conjunction with flow cytometric analysis (In Vivo MutaFlow(®)). While the percentage of reticulocytes (%RET) was markedly higher for pre-treatment blood samples from males compared to females (6.6% vs. 3.5%), this sex effect was slight or nonexistent at later time points. Treatment-related effects to %RET were generally modest owing to the 12-day interval between last exposure and blood sampling. Mean RET(CD59-) and RBC(CD59-) frequencies were consistently low in vehicle control animals of both sexes, with 77% of samples exhibiting mutant cell frequencies ≤1×10(-6) over study days 15-46. Treatment with each mutagen caused significant increases to mean RET(CD59-) and RBC(CD59-) frequencies. Whereas genotoxicant-induced RET(CD59-) values were maximal on day 15, induced RBC(CD59-) frequencies were highest at the last sampling time. Sex did not affect 1,3-propane sultone- or thiotepa-induced mutant cell frequencies. While ethyl carbamate-exposed females exhibited higher mean mutant cell frequencies compared to like-treated males, statistical significance was achieved only for RBC(CD59-) at one time point (7.6±1.0×10(-6) compared to 4.7±0.6×10(-6) on day 30). Thus, while some quantitative differences were evident, there were no qualitative differences in how males and females responded to three diverse mutagens. These data support the use of both sexes for Pig-a gene mutation studies.
Asunto(s)
Eritrocitos/efectos de los fármacos , Proteínas de la Membrana/genética , Mutación , Tiofenos/toxicidad , Tiotepa/toxicidad , Uretano/toxicidad , Animales , Antineoplásicos Alquilantes/toxicidad , Antígenos CD59/genética , Carcinógenos/toxicidad , Eritrocitos/metabolismo , Femenino , Frecuencia de los Genes , Masculino , Ratas Sprague-Dawley , Reticulocitos/efectos de los fármacos , Reticulocitos/metabolismo , Factores de TiempoRESUMEN
The number of studies examining the use of tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/auto-SCT) to treat high-risk or recurrent brain tumors is increasing. However, studies addressing the toxicity associated with tandem HDCT/auto-SCT, particularly during the second HDCT/auto-SCT, are very limited. For this reason, we retrospectively evaluated the toxicity of tandem HDCT/auto-SCT with carboplatin-thiotepa-etoposide (CTE) and cyclophosphamide-melphalan (CM) regimens when used to treat high-risk or recurrent brain tumors. A total of 109 patients who received a first HDCT/auto-SCT and 100 who proceeded to a second HDCT/auto-SCT between May 2005 and December 2013 were included. Hematologic recovery was rapid during both the first and second HDCT/auto-SCT. In the first HDCT/auto-SCT, mucositis-related gastrointestinal toxicity was frequent, and two (1.8 %) patients died from toxicity [one hepatic veno-occlusive disease (VOD) and one sepsis]. In the second HDCT/auto-SCT, mucositis-related toxicity was milder than in the first round. However, hepatic VOD frequency was high (20.0 %), and six (6.0 %) patients died from toxicity (four hepatic VODs, one asphyxia, and one sepsis). Multivariate analysis indicated that age younger than 8 years was the only significant predictor for hepatic VOD. All six patients who died from toxicity during the second HDCT/auto-SCT were younger than 9 years of age. This study demonstrates that tandem HDCT/auto-SCT using CTE/CM regimens was generally feasible. However, dose reduction during the second HDCT/auto-SCT in young children might be needed to decrease the death rate from toxicity.
Asunto(s)
Antineoplásicos Alquilantes/toxicidad , Neoplasias Encefálicas/terapia , Trasplante de Células Madre/efectos adversos , Adolescente , Adulto , Factores de Edad , Antineoplásicos Alquilantes/administración & dosificación , Carboplatino/administración & dosificación , Carboplatino/toxicidad , Niño , Preescolar , Terapia Combinada/efectos adversos , Etopósido/administración & dosificación , Etopósido/toxicidad , Femenino , Humanos , Lactante , Masculino , Melfalán/administración & dosificación , Melfalán/toxicidad , Estudios Retrospectivos , Tiotepa/administración & dosificación , Tiotepa/toxicidad , Trasplante Autólogo/efectos adversos , Adulto JovenAsunto(s)
Antineoplásicos Alquilantes/toxicidad , Carcinógenos/toxicidad , Esterilizantes Químicos/toxicidad , Tiotepa/toxicidad , Animales , Antineoplásicos Alquilantes/química , Esterilizantes Químicos/química , Femenino , Neoplasias/inducido químicamente , Neoplasias/epidemiología , Tiotepa/químicaRESUMEN
Zebrafish embryos have been shown to be a useful model for the detection of direct acting teratogens. This communication presents a protocol for a 3-day in vitro zebrafish embryo teratogenicity assay and describes results obtained for 10 proteratogens: 2-acetylaminofluorene, benzo[a]pyrene, aflatoxin B(1), carbamazepine, phenytoin, trimethadione, cyclophosphamide, ifosfamide, tegafur and thio-TEPA. The selection of the test substances accounts for differences in structure, origin, metabolism and water solubility. Apart from 2-acetylaminofluorene, which mainly produces lethal effects, all proteratogens tested were teratogenic in zebrafish embryos exposed for 3 days. The test substances and/or the substance class produced characteristic patterns of fingerprint endpoints. Several substances produced effects that could be identified already at 1 dpf (days post fertilization), whereas the effects of others could only be identified unambiguously after hatching at ≥ 3 dpf. The LC50 and EC50 values were used to calculate the teratogenicity index (TI) for the different substances, and the EC20 values were related to human plasma concentrations. Results lead to the conclusion that zebrafish embryos are able to activate proteratogenic substances without addition of an exogenous metabolic activation system. Moreover, the teratogenic effects were observed at concentrations relevant to human exposure data. Along with other findings, our results indicate that zebrafish embryos are a useful alternative method for traditional teratogenicity testing with mammalian species.
Asunto(s)
Pruebas de Mutagenicidad/métodos , Teratógenos/toxicidad , Pez Cebra , 2-Acetilaminofluoreno/toxicidad , Aflatoxina B1/toxicidad , Animales , Carbamazepina/toxicidad , Cinarizina/toxicidad , Ciclofosfamida/toxicidad , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Ifosfamida/toxicidad , Óvulo/efectos de los fármacos , Piracetam/toxicidad , Tegafur/toxicidad , Tiotepa/toxicidad , Trimetadiona/toxicidad , Pez Cebra/embriologíaRESUMEN
We previously demonstrated that Busulfan-Thiotepa (Bu-Thio) and ASCT effectively treated patients with locally relapsed medulloblastoma after surgery and conventional chemotherapy. We thus evaluated the administration of Bu-Thio in patients relapsing after conventional CNS irradiation. Patients were scheduled to receive Busulfan (600 mg/m(2)) and Thiotepa (900 mg/m(2)) and ASCT. Resection of residual tumour and additional irradiation were performed if necessary and feasible after Bu-Thio. Toxicity was compared to that observed in 35 patients treated without previous CNS irradiation. From 5/88 to 3/02, 15 patients were treated according to this strategy. Toxicity was significantly higher than that observed in unirradiated patients: thrombocytopenia <50,000/mm(3) lasting 56 days (13-732) (P=0.02) and 30 days (4-124), respectively, HVOD (10/15 and 12/35 patients, respectively) (P=0.06), neurological toxicity (8/15 vs 3/35 patients) (P=0.01). Tumour response was assessable in seven patients and consisted in two CR, three PR and two NR. Currently, two of 15 patients are alive with no evidence of disease. In conclusion, the toxicity of Bu-Thio was significantly more severe in previously irradiated patients. In spite of a high response rate, this strategy failed to improve the prognosis of previously irradiated patients with a relapse from a medulloblastoma.
Asunto(s)
Busulfano/administración & dosificación , Irradiación Craneana , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Meduloblastoma/terapia , Tiotepa/administración & dosificación , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Busulfano/toxicidad , Niño , Preescolar , Terapia Combinada , Femenino , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Lactante , Masculino , Meduloblastoma/complicaciones , Meduloblastoma/mortalidad , Síndromes de Neurotoxicidad/etiología , Inducción de Remisión/métodos , Tasa de Supervivencia , Tiotepa/toxicidad , Trombocitopenia/etiología , Trasplante Autólogo , Resultado del TratamientoRESUMEN
The aim of this study was to investigate thiotepa (TT) and fludarabine (Fluda) as a preparative regimen for allogeneic peripheral stem cell transplant in patients not eligible for a standard myeloablative regimen due to comorbidities and/or poor performance status. TT was given at a dose of 10 mg/kg over 2 days and Fluda at 125 mg/m(2) over 5 days. In all, 21 patients (14 male, seven female; 10 acute leukaemia, eight myelodysplastic syndrome, two non-Hodgkin's lymphoma, one Hodgkin's disease) were treated. The median age was 51 years (range 30-55 years). All patients achieved full donor-type chimaerism. Adverse events included mild nausea and vomiting in two patients and a slight increase of serum amylase in three. A total of 13 patients received RBC transfusions (median 6 U, range 1-23), and all received platelets (median 4 U, range 1-27). Four patients died of nonrelapse causes and five of relapse. The 1-year probabilities of transplant-related mortality and relapse were 19 and 29%, respectively. In total, 12 patients remain in complete remission (median follow-up: 786 days). The 3-year overall survival probability was 58%. We conclude that this regimen is feasible and well tolerated.
Asunto(s)
Neoplasias Hematológicas/terapia , Tiotepa/administración & dosificación , Acondicionamiento Pretrasplante/métodos , Vidarabina/análogos & derivados , Vidarabina/administración & dosificación , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Transfusión Sanguínea , Femenino , Supervivencia de Injerto , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Trasplante de Células Madre de Sangre Periférica/efectos adversos , Trasplante de Células Madre de Sangre Periférica/métodos , Recurrencia , Inducción de Remisión , Análisis de Supervivencia , Tiotepa/toxicidad , Quimera por Trasplante , Acondicionamiento Pretrasplante/efectos adversos , Trasplante Homólogo , Vidarabina/toxicidadAsunto(s)
Tiotepa/efectos adversos , Animales , Antineoplásicos Alquilantes/efectos adversos , Antineoplásicos Alquilantes/síntesis química , Antineoplásicos Alquilantes/química , Antineoplásicos Alquilantes/toxicidad , Pruebas de Carcinogenicidad , Carcinógenos/síntesis química , Carcinógenos/química , Carcinógenos/toxicidad , Células Cultivadas , Femenino , Regulación Gubernamental , Guías como Asunto , Humanos , Masculino , Ratones , Modelos Biológicos , Exposición Profesional/efectos adversos , Exposición Profesional/legislación & jurisprudencia , Primates , Conejos , Ratas , Tiotepa/síntesis química , Tiotepa/química , Tiotepa/toxicidad , Estados UnidosRESUMEN
High-dose chemotherapy (HD-CT) has a role in the potentially curative treatment of several tumours. The relative efficacies of the different regimens have not been studied in comparative trials, but it is clear that toxicities differ significantly between them. We analysed the immediate and long-term toxicity in the first 100 consecutive patients treated with the CTC regimen (cyclophosphamide 6000 mg m(-2), carboplatin 1600 mg m(-2) (or 20 mg ml(-1) min under the curve (AUC)) both as daily 1 h infusion, thiotepa 480 mg m(-2) as twice daily 30 min infusion, all divided over 4 consecutive days) followed by peripheral blood progenitor cell reinfusion (PBPC-Tx). Most patients had high-risk (n=86) or metastatic (n=4) breast cancer, or a germ cell tumour (n=8). Two patients (with a medulloblastoma and an aesthesioneuroblastoma, respectively) received CTC as off-protocol salvage regimen. The main toxicity was bone marrow suppression. Most patients had PBPC-Tx with granulocyte colony-stimulating factor (G-CSF), and the median time to neutrophil count 500 x 10(6) l(-1) and platelet count >20 x 10(9) l(-1) without transfusion independence was 10 (range 8-25) and 13 (8-60) days, respectively. The toxic death rate was 1%. Other frequent toxicities were neutropenic fever requiring antibiotics (n=65), central catheter-related infection (n=12) or a bleeding episode (n=48), mostly epistaxis (n=26). Reversible cardiac toxicity was seen in six patients and pulmonary events occurred in seven patients (infection (n=6), embolism (n=1)). Grade 3-4 gastrointestinal toxicity was frequent: nausea and vomiting 55%, diarrhoea 28% and mild liver toxicity (transaminase elevations) 9%. One patient pretreated with cisplatin had a kidney transplantation 8 years after HD-CT. Late complications included reversible radiation pneumonitis (n=12) and chronic heart failure (n=2). We found five second solid malignancies and two myelodysplasias. In conclusion, the CTC regimen is associated with a moderate, mainly reversible, toxicity. Future studies need to compare the efficacy and toxicity of the different HD-CT regimens.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Neoplasias de la Mama/tratamiento farmacológico , Carboplatino/toxicidad , Ciclofosfamida/toxicidad , Germinoma/tratamiento farmacológico , Tiotepa/toxicidad , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Médula Ósea/efectos de los fármacos , Carboplatino/administración & dosificación , Ciclofosfamida/administración & dosificación , Esquema de Medicación , Estudios de Seguimiento , Hemorragia/complicaciones , Humanos , Infecciones/complicaciones , Masculino , Persona de Mediana Edad , Países Bajos , Tiotepa/administración & dosificaciónRESUMEN
Fludarabine, thiotepa and total body irradiation (TBI) has been used as conditioning in haplo-identical transplantation. We studied this conditioning regimen in adults undergoing matched sibling transplantation and alternative donor transplantation. A total of 30 consecutive patients underwent matched related, haplo-identical related or matched unrelated donor transplantation with fludarabine, thiotepa and TBI conditioning. All but four had advanced hematologic malignancies. For haplo-identical transplant, ATG was added to the regimen. All patients received peripheral blood stem cells; these were T-cell depleted for 2-antigen or 3-antigen mismatched related transplantation. Additional graft-versus-host disease prophylaxis consisted of tacrolimus and mini-methotrexate. One recipient of haplo-identical transplant failed to engraft; all other evaluable patients had prompt engraftment. Four patients died of regimen-related toxicity. In all, 14 additional patients died of regimen-related causes including four from failure to thrive with persistent thrombocytopenia and four from delayed pulmonary toxicity. Six patients relapsed. Progression-free survival at 12 months was 47% (90% CI: 25-69%) for recipients of HLA-identical sibling transplants and 30% (90% CI: 14-46%) for all patients. Five of six long-term survivors have extensive chronic GVHD. As a result of the delayed complications and a relatively high recurrence rate, we abandoned this regimen.
Asunto(s)
Antineoplásicos Alquilantes/toxicidad , Neoplasias Hematológicas/terapia , Trasplante de Células Madre de Sangre Periférica/métodos , Acondicionamiento Pretrasplante/métodos , Vidarabina/análogos & derivados , Irradiación Corporal Total/efectos adversos , Adolescente , Adulto , Antineoplásicos Alquilantes/administración & dosificación , Niño , Terapia Combinada , Supervivencia de Injerto , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Enfermedad Injerto contra Huésped/inmunología , Haplotipos , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/mortalidad , Histocompatibilidad , Humanos , Persona de Mediana Edad , Trasplante de Células Madre de Sangre Periférica/efectos adversos , Trasplante de Células Madre de Sangre Periférica/mortalidad , Análisis de Supervivencia , Tiotepa/administración & dosificación , Tiotepa/toxicidad , Acondicionamiento Pretrasplante/efectos adversos , Acondicionamiento Pretrasplante/mortalidad , Trasplante Homólogo/inmunología , Insuficiencia del Tratamiento , Resultado del Tratamiento , Vidarabina/administración & dosificación , Vidarabina/toxicidad , Irradiación Corporal Total/métodosRESUMEN
A single high-dose cycle of chemotherapy can produce response rates in excess of 50%. However, disease-free survival (DFS) is 15-20% at 5 years. The single most important predictor of prolonged DFS is achieving a complete response (CR). Increasing the proportion of patients who achieve a complete response may improve disease-free survival. Women with metastatic breast cancer and at least a partial response (PR) to induction chemotherapy received three separate high-dose cycles of chemotherapy with peripheral blood progenitor support and G-CSF. The first intensification was paclitaxel (825 mg/m(2)), the second melphalan (180 mg/m(2)) and the third consisted of cyclophosphamide 6000 mg/m(2) (1500 mg/m(2)/day x 4), thiotepa 500 mg/m(2) (125 mg/m(2)/day x 4) and carboplatin 800 mg/m(2) (200 mg/m(2)/day x 4) (CTCb). Sixty-one women were enrolled and 60 completed all three cycles. Following the paclitaxel infusion most patients developed a reversible, predominantly sensory polyneuropathy. Of the 30 patients with measurable disease, 12 converted to CR, nine converted to a PR*, and five had a further PR, giving an overall response rate of 87%. The toxic death rate was 5%. No patient progressed on study. Thirty percent are progression-free with a median follow-up of 31 months (range 1-43 months) and overall survival is 61%. Three sequential high-dose cycles of chemotherapy are feasible and resulted in a high response rate. The challenge continues to be maintenance of response and provides the opportunity to evaluate strategies for eliminating minimal residual disease.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/secundario , Neoplasias de la Mama/terapia , Trasplante de Células Madre de Sangre Periférica , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Neoplasias de la Mama/mortalidad , Carboplatino/administración & dosificación , Carboplatino/toxicidad , Ciclofosfamida/administración & dosificación , Ciclofosfamida/toxicidad , Femenino , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Humanos , Melfalán/administración & dosificación , Melfalán/toxicidad , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Paclitaxel/toxicidad , Polineuropatías/inducido químicamente , Inducción de Remisión , Análisis de Supervivencia , Tasa de Supervivencia , Tiotepa/administración & dosificación , Tiotepa/toxicidadRESUMEN
Sixty-two adults underwent marrow or blood stem cell transplantation from an HLA-matched related donor using high-dose thiotepa, busulfan, and cyclophosphamide (TBC) as the preparative regimen for treatment of advanced myelodysplastic syndrome (MDS) (refractory anemia with excess blasts with or without transformation) or acute myelogenous leukemia (AML) past first remission. All evaluable patients engrafted and had complete donor chimerism. A grade 3-4 regimen-related toxicity occurred in eight (13%) patients, and a diagnosis of MDS was the only independent risk factor for grade 3-4 regimen-related toxicity (hazard ratio 9.25, P = 0.01). Day-100 treatment-related mortality (TRM) was 19%. Poor-prognosis cytogenetics increased the risk of day-100 TRM (hazard ratio 11.4, P = 0.003), and use of tacrolimus for graft-versus-host disease prophylaxis reduced the risk of day-100 TRM (hazard ratio 0.13, P = 0.027). For all patients, the three-year relapse rate was 43% (95% CI, 28%-58%). Refractoriness to conventional induction chemotherapy prior to transplantation was an independent risk factor for relapse (hazard ratio 10.8, P = 0.02). Three-year survival was 26% (95% CI, 14%-37%); survival rates were 29% for those transplanted for AML in second remission, 31% transplanted for AML in relapse, and 17% with MDS, and there were no independent risk factors for survival. TBC is an active preparative regimen for advanced AML. Patients with advanced MDS appeared to have a higher risk of toxicity and early mortality, and alternative preparative regimens should be considered for these patients.
Asunto(s)
Antineoplásicos Alquilantes/administración & dosificación , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicos/terapia , Acondicionamiento Pretrasplante , Trasplante Homólogo/normas , Adolescente , Adulto , Anemia Refractaria con Exceso de Blastos/terapia , Antineoplásicos Alquilantes/toxicidad , Trasplante de Médula Ósea/efectos adversos , Trasplante de Médula Ósea/mortalidad , Trasplante de Médula Ósea/normas , Busulfano/administración & dosificación , Busulfano/toxicidad , Ciclofosfamida/administración & dosificación , Ciclofosfamida/toxicidad , Femenino , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/mortalidad , Trasplante de Células Madre Hematopoyéticas/normas , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/toxicidad , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/mortalidad , Tiotepa/administración & dosificación , Tiotepa/toxicidad , Acondicionamiento Pretrasplante/normas , Trasplante Homólogo/efectos adversos , Resultado del TratamientoRESUMEN
The study was designed to evaluate the efficacy and safety of an intensive, tri-alkylator conditioning regimen, consisting of thiotepa, busulfan and cyclophosphamide (TBC), prior to autologous hematopoietic cell transplantation in patients with multiple myeloma (MM) and to analyze factors associated with outcome. One hundred and twenty patients with MM received high-dose chemotherapy with TBC followed by autologous bone marrow (n = 24) or peripheral blood stem cell (PBSC) transplantation (n = 96). Fifty-four patients had chemosensitive disease and 66 had refractory disease at the time of transplantation. The overall response rate was 81% and the complete remission (CR) rate was 26%. Patients with chemosensitive disease had a CR rate of 52% vs 5% for patients with refractory disease. Multivariable analysis determined disease status at transplant as the factor most likely associated with long survival. Estimated median survival was 48, 35 and 9 months for patients with chemosensitive, primary refractory or disease in refractory relapse, respectively. Short interval from diagnosis to transplant among patients with primary refractory disease and younger age were also favorable prognostic factors for survival. Patients with refractory disease pre-transplant who achieved remission criteria rapidly after treatment had a worse outcome than the slow responders. Treatment-related mortality with the introduction of PBSC and better supportive care was 4.8%. In conclusion, TBC is an effective and relatively well-tolerated intensive conditioning regimen in patients with MM. A more favorable outcome was observed in patients with chemosensitive disease and with early treatment for primary refractory disease. TBC merits further study in these subgroups and comparison with alternative regimens in prospective studies is warranted.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/normas , Mieloma Múltiple/terapia , Acondicionamiento Pretrasplante/métodos , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Busulfano/administración & dosificación , Busulfano/toxicidad , Ciclofosfamida/administración & dosificación , Ciclofosfamida/toxicidad , Femenino , Supervivencia de Injerto , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/mortalidad , Pronóstico , Inducción de Remisión , Análisis de Supervivencia , Tiotepa/administración & dosificación , Tiotepa/toxicidad , Factores de Tiempo , Acondicionamiento Pretrasplante/normas , Trasplante Autólogo/métodos , Trasplante Autólogo/normasRESUMEN
Modulation of DNA damage repair activity could lead to new approaches to reduce cytotoxic side effects of chemotherapy. N,N',N"-Triethylenethiophosphoramide (thioTEPA) induces the formation of amino-ethyl adducts of guanine, resulting in imidazole ring opening [formamidopyrimidine (Fapy)] and is associated with significant myelosuppression in dose-intensive therapies. In Escherichia coli, Fapy lesions are repaired by the Fapy-DNA glycosylase (Fpg) protein. We hypothesized that the expression of the Fpg could increase resistance of hematopoietic cells to thioTEPA-induced cytotoxicity. Expression of Fpg in bone marrow (BM) cells via a retrovirus vector was associated with demonstrable 8-oxodeoxyguanosine DNA glycosylase activity. BM cells were infected with a recombinant retrovirus, SF91, containing the Fpg gene and expressing the enhanced green fluorescence protein (EGFP) via an internal ribosomal entry site element. Control mice received BM transduced with the backbone containing IRES-EGFP alone. Fpg-transduced and GFP+ BM hematopoietic cells were resistant in vitro to thioTEPA at multiple concentrations. Mice transplanted with transduced cells were treated with four doses of thioTEPA (10 mg/kg) given over 7 weeks. Despite low transduction efficiency, peripheral blood leukocytes, hemoglobin, and platelet counts of thioTEPA-treated Fpg mice were significantly higher than treated control mice (P < 0.05). In addition, after treatment, the BM, spleen, and thymic cellularity as well as the number of GFP+ progenitor cells in the BM of treated mice were significantly higher than those of control group. Selection of Fpg-transduced cells in vivo was demonstrated by an increase in the mean fluorescence intensity of peripheral mononuclear cells of Fpg mice compared with pretreatment value. In addition, a significant increase in the EGFP-bright cells was demonstrated, suggesting preferential survival of high-expressing hematopoietic cells. Similar results were demonstrated in vitro with primary BM expressing the human functional counterpart of Fpg, OGG1. These results show that expression of the Fpg or hOGG1 protein protects hematopoietic cells from thioTEPA-induced DNA damage and suggest that a high level of expression of these repair proteins is required to establish resistance to this drug. Expression of Fpg and/or OGG1 may provide an novel approach to preventing thioTEPA-induced toxicity of primary hematopoietic cells.
Asunto(s)
Antineoplásicos Alquilantes/toxicidad , Reparación del ADN , Proteínas de Escherichia coli , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/enzimología , N-Glicosil Hidrolasas/biosíntesis , N-Glicosil Hidrolasas/genética , Tiotepa/toxicidad , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , ADN-Formamidopirimidina Glicosilasa , Femenino , Técnicas de Transferencia de Gen , Vectores Genéticos/genética , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/fisiología , Humanos , Inmunofenotipificación , Ratones , Ratones Endogámicos C57BL , N-Glicosil Hidrolasas/sangre , Provirus/genética , Retroviridae/genética , Bazo/citología , Bazo/efectos de los fármacos , Timo/citología , Timo/efectos de los fármacos , Transducción Genética , Integración ViralRESUMEN
Eighty patients receiving hematological stem cell transplantation (HCT) with a preparative regimen consisting of total body irradiation (12.5 Gy), cyclophosphamide (4000 or 4500 mg/m2), and thiotepa (400 mg/m2) were evaluated for the development of cardiac toxicity. Patients in whom the pretransplant cumulative dose of anthracycline was more than or equal to 300 mg/m2 showed a lower left ventricular ejection fraction (EF) before HCT compared to patients with less than 300 mg/m2 (0.61 +/- 0.09 vs 0.67 +/- 0.06, P = 0.0010). Patients who had undergone more than or equal to six courses of chemotherapy showed a decreased EF before HCT compared to those after less than six courses (0.67 +/- 0.05 vs 0.63 +/- 0.09, P = 0.03). Three of seven patients (43%) whose pretransplant EF had been less than or equal to 0.55 developed severe cardiac toxicity, characterized by congestive heart failure (CHF) compared with none of 83 patients (0%) whose pretransplant EF had been more than 0.55 (P = 0.00026). Of the three patients who developed severe cardiac toxicity, two were given more than 300 mg/m2 of cumulative anthracycline and underwent 23 courses and six courses of chemotherapy, while the other patient received only two courses of chemotherapy with a total dose of 139 mg/m2 of anthracycline. These results indicate that an increased cumulative dose of anthracycline and number of chemotherapy treatments are correlated with a decrease of the EF and that the EF before HCT is useful for predicting the risk of cardiac complications for recipients who have received chemotherapy.
Asunto(s)
Insuficiencia Cardíaca/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Ciclofosfamida/administración & dosificación , Ciclofosfamida/toxicidad , Relación Dosis-Respuesta a Droga , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Masculino , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Volumen Sistólico/fisiología , Tiotepa/administración & dosificación , Tiotepa/toxicidad , Irradiación Corporal TotalRESUMEN
A hypothesis on the genetic determination of periodic fluctuations of the sensitivity to the mutagen thioTEPA in successive inbred generations of mice has been earlier put forward. This study was the initial stage of testing this hypothesis. The mouse strain CBA/LacY was divided into two substrains, which differed in the rate of generation change. As a result, two colonies of isogenic mice differing by 10-12 generations with respect to the inbred age were obtained. Both the rate and range of variations in the mutagen sensitivity (four generations per period of the cycle and 20-40% of cells with chromosome aberrations after the standard dose of 2.5 mg/kg of thioTEPA, respectively) in 19 generations of the "fast" substrain agreed with earlier data. The response of the "slow" substrain corresponded to the expected response of the "fast" substrain after the given number of generations. In the mice of generations F142 and F146 that lived simultaneously and differed in thioTEPA sensitivity, the effects of the carcinogen benzo[a]pyrene (BaP) were significantly different. The levels of these effects corresponded to the levels of the responses to thioTEPA. The data obtained agree with the hypothesis tested.
Asunto(s)
Benzo(a)pireno/toxicidad , Endogamia , Mutágenos/toxicidad , Tiotepa/toxicidad , Animales , Aberraciones Cromosómicas , Ratones , Ratones Endogámicos CBARESUMEN
Forty-two patients (29 newly diagnosed) with high grade gliomas (n = 37), medulloblastoma (n = 2) or non-biopsied tumors (n = 3) with supratentorial (n = 24), brain stem (n = 11), posterior fossa (n = 5) or spinal (n = 2) location were eligible for this study with adequate organ function and no bone marrow tumor infiltration. Median patient age was 12.2 years (range, 0.7-46.8). A total of 600 mg/m2 BCNU, 900 mg/m2 thiotepa and 1500 or 750 mg/m2 etoposide (VP-16) was administered followed by autologous bone marrow reinfusion (ABMR). Twenty-one newly diagnosed patients received local irradiation (RT) post ABMR. Nine early deaths were observed (21%), as well as one secondary graft failure. Half of the patients aged 18 years or older experienced toxic deaths, whereas only 15% of patients younger than 18 years experienced toxic death (P = 0.05). Of 25 evaluable newly diagnosed patients, 20% achieved complete remission (CR) and 4% partial remission (PR), while 28% remained in continuing complete remission (CCR) and 44% remained with stable disease prior to RT. Of eight evaluable patients with recurrent disease, one achieved CR and two PR, while one remained in CCR and four with stable disease for 1 to 110.2 months. Overall survival was 36%, 24% and 17% at 1, 2 and 3 years following ABMR, with three newly diagnosed patients and one patient treated for recurrent disease being alive, without disease progression 64.4, 67.0, 86.3 and 110.2 months after ABMR, respectively. The combination of high-dose BCNU/ thiotepa/VP-16 has substantial toxicity but definite activity for high risk CNS tumors. Similar protocols with lower toxicity merit further evaluation in both newly diagnosed and recurrent CNS tumors.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea , Neoplasias del Sistema Nervioso Central/complicaciones , Neoplasias del Sistema Nervioso Central/terapia , Adolescente , Adulto , Carmustina/administración & dosificación , Carmustina/toxicidad , Neoplasias del Sistema Nervioso Central/mortalidad , Enfermedad Hepática Inducida por Sustancias y Drogas , Niño , Preescolar , Terapia Combinada , Supervivencia sin Enfermedad , Etopósido/administración & dosificación , Etopósido/toxicidad , Femenino , Supervivencia de Injerto , Enfermedades Hematológicas/inducido químicamente , Humanos , Lactante , Enfermedades Renales/inducido químicamente , Enfermedades Pulmonares/inducido químicamente , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica/inducido químicamente , Enfermedades del Sistema Nervioso/inducido químicamente , Tasa de Supervivencia , Tiotepa/administración & dosificación , Tiotepa/toxicidad , Trasplante Autólogo , Resultado del TratamientoRESUMEN
UCN-01 is undergoing Phase I evaluation and is a candidate for combination strategies in the clinic. UCN-01 has been shown to have a variety of effects on cellular targets and the cell cycle. It has also been reported to sensitize cells to several clinical drugs in vitro, possibly in a manner related to p53 status. Thus, combinations of UCN-01 with a series of clinical agents in variety of cell lines have been investigated in vitro. Certain cell lines demonstrated synergistic interactions with combinations of UCN-01 (20-150 nM) and thiotepa, mitomycin C, cisplatin, melphalan, topotecan, gemcitabine, fludarabine or 5-fluorouracil. In contrast, UCN-01 combinations with the antimitotic agents, paclitaxel and vincristine, or topoisomerase II inhibitors, adriamycin and etoposide, did not result in synergy, only in additive toxicity. Cells with non-functional p53 were significantly more susceptible to the supra-additive effects of certain DNA-damaging agents and UCN-01 combinations, than cells expressing functional p53 activity. In contrast, there was no significant relationship between p53 status and susceptibility to synergy between antimetabolites and UCN-01. The mechanism behind the observed synergy appeared unrelated to effects on protein kinase C or abrogation of the cell cycle in G2. Moreover, increased apoptosis did not fully explain the supradditive response. These data indicate that UCN-01 sensitizes a variety of cell lines to certain DNA-damaging agents (frequently covalent DNA-binding drugs) and antimetabolites in vitro, but the mechanism underlying this interaction remains undefined.