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Bone Marrow Toxicity (bone + marrow_toxicity)
Selected AbstractsModel-based design of chemotherapeutic regimens that account for heterogeneity in leucopoeniaBRITISH JOURNAL OF HAEMATOLOGY, Issue 6 2006Markus Scholz Summary Patients treated with multicycle chemotherapy can exhibit large interindividual heterogeneity of haematotoxicity. We describe how a biomathematical model of human granulopoiesis can be used to design risk-adapted dose-dense chemotherapies, leading to more similar leucopoenias in the population. Calculations were performed on a large data set for cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP)-like chemotherapies for aggressive non-Hodgkin lymphoma. Age, gender, Eastern Cooperative Oncology Group performance status, lactate dehydrogenase and the degree of leucopoenia within the first therapy cycle were used to stratify patients into groups with different expected severity of leucopoenia. We estimated risk-specific bone marrow toxicities depending on the drug doses administered. These toxicities were used to derive risk-adapted therapy schedules. We determined different doses of cyclophosphamide and additional etoposide for patients treated with CHOP-14. Alternatively, the model predicted that further reductions of cycle duration were feasible in groups with low toxicity. We also used the model to identify appropriate granulocyte colony-stimulating factor (G-CSF) schedules. In conclusion, we present a method to estimate the potential of risk-specific dose adaptation of different cytotoxic drugs in order to design chemotherapy protocols that result in decreased diversity of leucopoenia between patients, to develop dose-escalation strategies in cases of low leucopoenic reaction and to determine optimal G-CSF support. [source] Cepharanthine activates caspases and induces apoptosis in Jurkat and K562 human leukemia cell linesJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2001Jianghong Wu Abstract Cepharanthine (CEP) is a known membrane stabilizer that has been widely used in Japan for the treatment of several disorders such as anticancer therapy-provoked leukopenia. We here report that apoptosis was induced by low concentrations (1,5 ,M) of CEP in a human leukemia T cell line, Jurkat, and by slightly higher concentrations (5,10 ,M) in a human chronic myelogenous leukemia (CML) cell line K562, which expresses a p210 antiapoptotic Bcr-Abl fusion protein. Induction of apoptosis was confirmed in both Jurkat and K562 cells by DNA fragmentation and typical apoptotic nuclear change, which were preceded by disruption of mitochondrial membrane potential and were induced through a Fas-independent pathway. CEP treatment induced activation of caspase-9 and -3 accompanied by cleavage of PARP, Bid, lamin B1, and DFF45/ICAD in both Jurkat and K562 cells, whereas caspase-8 activation and Akt cleavage were observed only in Jurkat cells. The CEP-induced apoptosis was completely blocked by zVAD-fmk, a broad caspase inhibitor. Interestingly, CEP treatment induced remarkable degradation of the Bcr-Abl protein in K562 cells, and this degradation was prevented partially by zVAD-fmk. When used in combination with a nontoxic concentration of herbimycin A, lower concentrations (2,5 ,M) of CEP induced obvious apoptosis in K562 cells with rapid degradation or decrease in the amount of Bcr-Abl and Akt proteins. Our results suggest that CEP, which does not have bone marrow toxicity, may possess therapeutic potential against human leukemias, including CML, which is resistant to anticancer drugs and radiotherapy. J. Cell. Biochem. 82: 200,214, 2001. © 2001 Wiley-Liss, Inc. [source] Inhibition of Hematopoietic Progenitor Cell Proliferation by Ethanol in Human Immunodeficiency Virus Type 1 Tat-Expressing Transgenic MiceALCOHOLISM, Issue 3 2001Om Prakash Background: A number of hematological abnormalities are associated with both human immunodeficiency virus type 1 (HIV-1) infection and alcohol abuse. There is little information on how alcohol abuse might further influence the survival and growth of hematopoietic progenitors in HIV-infected individuals in the presence of immune system abnormalities and anti-HIV drugs. Because there is evidence that viral transactivator Tat itself can induce hematopoietic suppression, in this study we examined the role of ethanol as a cofactor in transgenic mice that expressed HIV-1 Tat protein. Methods: Tat transgenic mice and nontransgenic littermates were given ethanol (20% v/v) and the anti-HIV drug 3,-azido-3,-deoxythymidine (AZT; 1 mg/ml) in drinking water. Immunosuppression in mice was induced by weekly intraperitoneal injections of anti-CD4 antibody. Hematopoiesis was examined by erythroid colony forming unit (CFU-E) and granulocyte/macrophage colony-forming unit (CFU-GM) assays of the bone marrow progenitor cells. Results: Administration of ethanol for 7 weeks resulted in a 50% decrease in the proliferative capacity of CFU-E- and CFU-GM-derived progenitors from transgenic mice compared with that of ethanol-treated nontransgenic controls. Similar decreases also were observed in transgenic mice treated with AZT or a combination of AZT and ethanol. Furthermore, ethanol and AZT were significantly more toxic to the granulopoietic progenitors (40,50% inhibition) than to the erythropoietic progenitors (10,20% inhibition) in Tat transgenic mice. Although a 10 day exposure of Tat transgenic and nontransgenic mice to a combination of ethanol and AZT had no suppressive effect on the erythropoietic and granulopoietic progenitor cells, there was a marked decrease (40,60%) in CFU-GM in mice made immunodeficient by CD4+ T-lymphocyte depletion. The ethanol-treated Tat transgenic mice but not the nontransgenic littermates also showed a significant decrease (25%) in CFU-GM. Conclusion: Our in vivo study strongly suggests that ethanol ingestion in HIV-1-infected individuals, particularly those on antiretroviral drugs, might increase bone marrow toxicity and contribute to HIV-1-associated hematopoietic impairment. [source] Methotrexate in psoriasis: 26 years' experience with low-dose long-term treatmentJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 5 2000U-F. Haustein Abstract Objective,To evaluate the efficacy, safety and side-effects of methotrexate (MTX) in psoriasis. Design,A 26-year retrospective study. Setting,Department of Dermatology, Leipzig University, Leipzig, Germany. Patients,One hundred and fifty-seven patients with extensive plaque psoriasis, erythrodermic, pustular and arthropathic forms, were treated with low-dose methotrexate (15,20 mg maximum weekly dosage [Weinstein schedule]), the majority for long-term periods. The mean cumulative dose was 3394 mg, the mean duration 237 weeks. Results,The effect of MTX treatment was good in 76%, moderate in 18% and poor in 6% of subjects; 61% experienced side-effects, most frequently due to liver function abnormalities, bone marrow suppression, nausea, gastric complaints and hair loss. In 20% of cases the subjects were forced to discontinue therapy; 9% refused therapy due to physical and psychological discomfort, 2% wanted to become pregnant, 16% were lost to follow-up, 6% died from multimorbidity and old age. Three subjects (2%) developed cancer of the lung, breast or cervix uteri, possibly in relation to long-term MTX treatment. Altogether there were no deaths or life-threatening side-effects attributable to MTX treatment, and no cases of progressive liver cirrhosis apart from two extensive skin necroses due to overdosage (misunderstanding, suicidal attempt) that were treated successfully with citrovorum factor. Conclusion,Low-dose MTX (<15,20 mg/week) is an effective therapy for extensive and severe forms of psoriasis if patients are selected carefully and monitored regularly, particularly with respect to liver and bone marrow toxicity. This helps to reduce severe side-effects even during long-term treatment. Drug interactions must be avoided. MTX therapy according to the guidelines is relatively safe and still has a place in the systemic treatment of psoriasis with 40 years of experience and an acceptable safety record. [source] Utility of azathioprine metabolite measurements in post-transplant recurrent autoimmune and immune-mediated hepatitisPEDIATRIC TRANSPLANTATION, Issue 6 2004Carolina Rumbo Abstract:, Patients with post-transplant immune-mediated hepatitis (IMH) and recurrent autoimmune hepatitis (RAIH) have a poor outcome and a higher need for retransplantation. Azathioprine (AZA) is used as adjunctive immunosuppression after transplantation; optimizing its dose may be a key point in preserving graft function. Complications of high AZA dosing make dose escalation potentially problematic. Our aim was to correlate AZA metabolite levels with therapeutic effects, toxicity, and adherence to medication in children with IMH and RAIH. Charts of 14 patients were retrospectively reviewed. The post-transplant diagnosis was based on liver biopsy and autoimmune markers. AZA was prescribed after establishing the post-transplant diagnosis. AZA was started at 1.1 (1.0,1.8) mg/kg/day. Routine biochemical studies, tacrolimus levels, 6-thioguanine (6-TG) and 6-methylmercaptopurine levels were assessed every 8 wk. AZA dose was routinely adjusted to achieve 6-TG levels between 235 and 450 pmol per 8 × 108 RBC. A total of 92 samples from 14 patients were reviewed. Four patients were excluded because of non-adherence. AZA dose was increased by 245% resulting in eight of 10 patients in the target range; no hepatic or bone marrow toxicity was observed. ALT levels and steroid requirements were significantly reduced (p < 0.05). The AZA dose required to achieve target 6-TG levels was significantly greater in children <10 yr. AZA metabolite testing in children post-liver transplant is useful in assessing adherence to medication and it is potentially helpful in optimizing medication dosing. In younger children the AZA dose requirements were two to four times higher than previously reported standard doses. [source] Preclinical evaluation of carcinoembryonic cell adhesion molecule (CEACAM) 6 as potential therapy target for pancreatic adenocarcinoma,THE JOURNAL OF PATHOLOGY, Issue 3 2009Laura A Strickland Abstract Despite the availability of new targeted therapies, ductal pancreatic adenocarcinoma continues to carry a poor prognosis. Carcinoembryonic antigen-related cell adhesion molecule (CEACAM)6 has been reported as a potential biomarker and therapy target for this malignancy. We have evaluated CEACAM6 as a potential therapy target, using an antibody,drug conjugate (ADC). Expression of CEACAM6 in pancreatic adenocarcinomas was determined using immunohistochemistry on tissue microarrays. The expression pattern in granulocytes and granulocytic precursors was measured by flow cytometry. Murine xenograft and non-human primate models served to evaluate efficacy and safety, respectively. Robust expression of CEACAM6 was found in > 90% of invasive pancreatic adenocarcinomas as well as in intraepithelial neoplastic lesions. In the granulocytic lineage, CEACAM6 was expressed at all stages of granulocytic maturation except for the early lineage-committed precursor cell. The anti-CEACAM6 ADC showed efficacy against established CEACAM6-expressing tumours. In non-human primates, antigen-dependent toxicity of the ADC consisted of dose-dependent and reversible depletion of granulocytes and their precursors. This was associated with preferential and rapid localization of the antibody in bone marrow, as determined by sequential in vivo PET imaging of the radiolabelled anti-CEACAM6. Localization of the radiolabelled tracer could be attenuated by predosing with unlabelled antibody confirming specific accumulation in this compartment. Based on the expression pattern in normal and malignant pancreatic tissues, efficacy against established tumours and limited and reversible bone marrow toxicity, we propose that CEACAM6 should be considered for an ADC-based therapy approach against pancreatic adenocarcinomas and possibly other CEACAM6-positive neoplasms. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Concomitant weekly cisplatin and altered fractionation radiotherapy in locally advanced head and neck cancerCANCER, Issue 19 2010Heather E. Newlin MD Abstract BACKGROUND: Both concomitant chemotherapy and altered fractionation radiotherapy (RT) have been shown to improve outcomes for patients with locoregionally advanced head and neck squamous cell carcinomas. However, both strategies also increase acute toxicity, and it is questionable whether the 2 can be safely combined. Traditional concomitant chemotherapy regimens include high-dose cisplatin given at 100 mg/m2 every 3 weeks. The authors' purpose was to report efficacy and toxicity after weekly cisplatin (30 mg/m2/wk) concurrent with altered fractionation RT. METHODS: One hundred twenty-one patients with American Joint Committee on Cancer stages II (3%), III (13%), or IV (84%) squamous cell carcinomas of the oropharynx (70%), hypopharynx (20%), or larynx (10%) were treated between 2000 and 2006 at the University of Florida with hyperfractionated RT (55 patients) or concomitant boost RT (66 patients) and concomitant cisplatin (30 mg/m2/wk). RESULTS: Median follow-up was 2.9 years; median follow-up on survivors was 3.6 years. Seventy-nine percent of patients completed ,6 cycles of chemotherapy; 94% received ,7200 centigrays. Seven (6%) patients changed from cisplatin to carboplatin because of bone marrow toxicity. Gastrostomy tube feeding was required in 54% of patients either before (16%) or during RT (38%). Two (1.6%) patients died from therapy-related complications. The 5-year outcomes were: local control, 83%; locoregional control, 79%; distant metastasis-free survival, 88%; cause-specific survival, 76%; and overall survival, 59%. Seven (6%) patients had severe late complications. Three (3%) patients required a permanent gastrostomy tube. CONCLUSIONS: Concomitant weekly cisplatin with altered fractionation RT is a safe and effective treatment regimen. Cancer 2010. © 2010 American Cancer Society. [source] | ||||||||||