Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lipids extracted from doxorubicin-resistant murine leukemia cells (P388/ADR) contained greater relative amounts of myristic and palmitoleic acids than lipids from sensitive cells (P388). This was seen in both the phospholipid and neutral lipid fractions under two nutritional conditions. Correspondingly in P388/ADR cells, myristic acid comprised a greater proportion of the products of the fatty acid synthetase system, and acyl-CoA 9-desaturase activity was transiently greater than in P388. Similar alterations in myristic acid synthesis were exhibited by DC3F/AD X, N417/VP-16, and P388/AZQ30U cells but not by CHRC5 or HL60/AR cells. This alterations was independent of alterations in the P180 glycoprotein and might be linked via the myristoylation of proteins to a different mechanism of drug resistance. Doxorubicin-resistant P388/ADR cells also exhibited a much higher rate of oxidative energy production.
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PMID:Differences in myristic acid synthesis and in metabolic rate for P388 cells resistant to doxorubicin. 208 96

We present a case of acute megakaryoblastic leukemia identified by electron microscopy and platelet-specific antibodies. The histological examination of bone marrow showed distinct myelofibrosis. In accordance with recent communications, low-dose cytosine arabinoside treatment (20 mg twice daily s.c. over 21 days) was initiated. The subsequent bone marrow examination showed a severe hypoplasia with persistent blasts. Amsacrine and VP-16 were given without success. Finally the patient died of septicemia without proof of pathogen uninfluenced by antibiotic and antiseptic therapy 6 weeks after diagnosis. Our case report confirms the poor prognosis of acute megakaryoblastic leukemia.
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PMID:Acute megakaryoblastic leukemia: a case report. 218 29

We studied the effects of two modulators of multidrug resistance (MDR), cyclosporine and verapamil, on the cytotoxicity of etoposide (VP-16) in normal human bone marrow; two human leukemia cell lines, K562 and CEM; their MDR variants, K562/DOX and CEM/VLB; and mixtures of normal marrow and leukemic cells. VP-16 was selectivity toxic to the parental leukemic cells, with IC-50 values of 2 microM for CEM cells, 1.5 microM for K562 cells, and 12 microM for normal marrow CFU-GM. This selectivity was lost in the MDR variant leukemia cells, with IC-50s of 20 microM in K562/DOX and 8 microMs in CEM/VLB. Cyclosporine, 6 microMs, and verapamil, 20 microM, alone were nontoxic to bone marrow CFU-GM, and did not significantly increase the toxicity of VP-16 to normal marrow cells or to the two drug-sensitive leukemic cell lines. However, cyclosporine specifically enhanced the cytotoxicity of VP-16 in the MDR leukemia cells, reducing the IC-50 to the same level as the parental sensitive cells. Verapamil was considerably less effective. In a mixing experiment that included K562/DOX cells and normal bone marrow, cyclosporine increased the toxicity of VP-16 to the resistant leukemic cells by nearly 20-fold. Because the cytotoxic effect of cyclosporine is additive for resistant tumor cells, its combination with VP-16 may be useful in the purging of contaminating tumor cells prior to autologous bone marrow transplantation.
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PMID:Modulation of etoposide (VP-16) cytotoxicity by verapamil or cyclosporine in multidrug-resistant human leukemic cell lines and normal bone marrow. 222 79

To further evaluate possible non-cross-resistant regimens in Hodgkin's disease, a phase II trial utilizing antimetabolites and etoposide was initiated by the Cancer and Leukemia Group B (CALGB). Etoposide was included because of its known efficacy in relapsed Hodgkin's disease and to evaluate for synergy with an alkylating agent and vincristine. Cytosine arabinoside and methotrexate were included to evaluate their effectiveness in rapidly growing resistant disease. Forty-two patients with previously treated Hodgkin's disease were entered, of which 37 are evaluable for response and toxicity. All patients had at least 2 prior regimens of chemotherapy and 59% had additional radiation therapy. Complete and partial response was observed in 61%; there were 32% complete responders. Duration of complete response was a median of 8 months (range 2-28+ months). Duration of partial response was 7 months (range 1-17 months). Three patients remain in complete remission at 19, 19, and 28 months. Major toxicity was hematologic with severe or life-threatening toxicity in 54%. There was one patient with a fatal infection. Non-hematologic toxicity, save for nausea and vomiting, was mild and uncommon. There were two fatal and one severe pulmonary toxicities reported in patients who had previous exposure to bleomycin and mediastinal radiation. Three had interstitial pneumonitis and one pulmonary emboli. The interstitial pneumonitis was thought to be drug related. Survival of the entire group is estimated at 61% at 12 months. We conclude that MOPLACE is an effective regimen with an appreciable complete response rate in this heavily pretreated group of patients. Hematologic and pulmonary toxicities are severe and may necessitate dose modifications. The use of etoposide containing combinations requires further study as primary therapy in untreated patients.
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PMID:Phase II study of MOPLACE chemotherapy for patients with previously treated Hodgkin's disease: a CALGB study. 223 20

The West Japan Pediatric Oncology Group studied the treatment of pediatric malignant tumors with VP-16 from December 1984 to March 1988. Study subjects were divided into two groups. One group received only VP-16, while the other received VP-16 combined with other anti-tumor agents. VP-16 evaluation was possible in a total of 116 cases. The efficacy rate was calculated by considering both complete and partial remission as effective. The efficacy rate for VP-16 alone was 87.5% for primary cases of ANLL and 100% for primary cases of histiocytosis. The efficacy rates for combination therapy were as follows: 92.6% for primary cases of ANLL, 66.7% for primary cases of histiocytosis, 45.5% for relapsed cases of ANLL and 66.7% for relapsed cases of ALL. Bone marrow suppression was seen in the form of leukopenia and thrombocytopenia for 2 to 3 weeks after VP-16 administration. Alopecia, mucositis and gastrointestinal symptoms were also observed, but they presented no significant problem. From our results, we believe that chemotherapy including VP-16 is effective for remission induction therapy in primary cases of ANLL and for salvage therapy in relapsed leukemia. Additionally, VP-16 is considered to be effective for the treatment of histiocytosis.
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PMID:Treatment of pediatric malignant tumors with VP-16. West Japan Pediatric Oncology Group. 223 3

The effect of etoposide-induced deoxyribonucleic acid (DNA) damage and its effect on nucleotide pools were examined in murine leukemia L1210 cells. Etoposide (15 mg/kg) was administered intraperitoneally on the third day after peritoneal inoculation of 1 x 10(6) L1210 cells. The dosage of etoposide produced 175% of the increase of lifespan as described previously. Strand breaks in DNA occurred within 10 min after i.p. injection, but as the time interval between injection and removal of the cells from the mice was elongated to 1 and 3 h, the continuous repairing of DNA was observed. At 6 h after the injection, the maximum concentration of DNA was located in the vicinity of that of control. In our previous study, ara-C was most effective when given at 3 to 6 h after the administration of etoposide. The sensitivity to ara-C might increase during the repairing period from the etoposide-induced DNA damage. All four dNTPs increased progressively within 6 h up to 3-fold of control. The changes in rNTPs were similar, but the degree of the changes was smaller than that of dNTPs. These changes in dNTPs and rNTPs would be an important factor for the combination to determine the antitumor effect of etoposide and nucleoside analogues.
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PMID:[Etoposide-induced deoxyribonucleic acid (DNA) damage and its effects on nucleotide pools in murine leukemia L1210 cells]. 226 79

The epipodophyllotoxines VP-16 and VM-26 are chemically closely related. VM-26 has been found to be considerably more potent than VP-16 in vitro in a number of investigations. Although the drugs have been known for greater than 20 years, they have not been compared at clearly defined equitoxic doses on an optimal schedule in vivo and it has not been clarified as to whether a therapeutic difference exists between them. A prolonged schedule is optimal for both drugs; accordingly we determined the toxicity in mice using a 5-day schedule. The dose killing 10% of the mice (LD10) was 9.4 mg/kg daily (95% confidence limits, 7.4-11.8) for VP-16 and 3.4 (2.5-4.5) mg/kg daily for VM-26. In vitro, we found VM-26 to be 6-10 times more potent than VP-16 in a clonogenic assay on murine tumors P388 and L1210 leukemia and Ehrlich ascites. This pattern was also demonstrated in a multidrug-resistant subline of Ehrlich selected for resistance to daunorubicin (Ehrlich/DNR+), as it was 30 times less sensitive than Ehrlich cells to both VP-16 and VM-26. Using 90%, 45%, and 22% of the LD10 on the same murine tumors in vivo, we found that the effect of the two drugs was equal as evaluated by both the increase in life span and the number of cures. The drugs were also compared in nude mice inoculated with human small-cell lung cancer lines OC-TOL and CPH-SCCL-123; however, they were more toxic to the nude mice and only a limited therapeutic effect was observed. In conclusion, the complete cross-resistance between the two drugs suggests that they have an identical antineoplastic spectrum. VM-26 was more potent than VP-16 in vitro; however, this was not correlated to a therapeutic advantage for VM-26 over VP-16 in vivo.
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PMID:Antitumor activity of the two epipodophyllotoxin derivatives VP-16 and VM-26 in preclinical systems: a comparison of in vitro and in vivo drug evaluation. 226 55

Eighty-seven consecutive children and young adults with acute nonlymphocytic leukemia (ANLL) were treated uniformly with induction chemotherapy based on daunorubicin and cytarabine (ara-C), with the addition of etoposide (VP-16) and azacytidine (5-Az) for refractory patients. Of the 65 patients who entered complete remission, 42 were eligible for assessment of response to intensive chemotherapy consisting of four pairs of drugs administered in sequential fashion. Nineteen others with available histocompatibility locus antigen (HLA)-compatible donors were assigned to receive allogeneic bone marrow transplants within 16 weeks from their dates of complete remission. Durations of continuous complete remission (CCR) in the two groups were not significantly different at a median follow-up time of 6 years (P = .30 by log-rank analysis). Kaplan-Meier estimates of CCR probabilities (+/- SE) at 6 years were 43% +/- 13% (transplantation) and 31% +/- 7% (sequential chemotherapy). Postremission failures in the sequential chemotherapy group resulted from bone marrow relapse in 23 of 29 patients (79%), whereas in the transplantation group, failures were equally divided between marrow relapse and transplantation-related complications of graft-versus-host disease (GVHD) or infection due to the immunosuppressive effects of ablative chemotherapy. Comparison of hematologic remission curves indicated a significant advantage for marrow transplantation in terms of systemic leukemia control (P = .06). Thus, in programs of intensive chemotherapy of the type described here, allogeneic marrow transplantation should be seriously considered as alternative therapy for patients in first remission who have an HLA-matched sibling donor, provided that effective methods for control of transplant-related complications are available.
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PMID:Allogeneic bone marrow transplantation in a program of intensive sequential chemotherapy for children and young adults with acute nonlymphocytic leukemia in first remission. 229 72

Diaziquone (AZQ) and etoposide (VP-16) were administered as simultaneous 5-day continuous infusions to 27 patients with acute leukemia (22 with acute myeloid leukemia (AML), three with chronic myeloid leukemia in blast crisis (CML-B), and two with acute lymphocytic leukemia) at four different doses in a phase I trial. Gastrointestinal toxicity, primarily stomatitis, was dose limiting, occurring in six of 10 patients at the highest dose level. Diarrhea was the only other grade 3 toxicity noted (three of 10 at the highest dose level). The duration of bone marrow aplasia was excessive at the highest dose (median 48 days to granulocytes greater than 500/mm3, range 33-67) but acceptable (31 days) at the maximum tolerated dose: AZQ 28 mg/m2/day x 5 days, VP-16 150 mg/m2/day x 5 days. Complete remissions were seen in seven patients (six AML, one CML-B) and a partial remission in one patient with AML. The median duration of unmaintained complete remission was 3 months (range 1.5-26+).
Leukemia 1990 Mar
PMID:Continuous infusion diaziquone and etoposide: a phase I study in adult patients with acute leukemia. 231 18

A phase II study was conducted by the Cancer and Leukemia Group B (CALGB) in patients with refractory and relapsed Hodgkin's disease (HD) to assess the activity of the combination of etoposide and cis-platin. Twenty-seven patients were entered; 22 were evaluated for this report. Treatment consisted of etoposide (VP-16), 80 mg/m2 IV over 1 hour and cis-platin, 20 mg/m2 IV over 1/2-1 hour; both agents were given daily for 5 days and repeated every 21 days. All patients had received at least 2 prior chemotherapy regimens, had measurable disease, and most (86%) had a performance status of 0-1. In the 22 evaluable patients, there were 4 complete responses (18%) and 4 partial responses, for an overall response rate of 36% (95% Cl: 17.2%, 59.3%). Response duration was from 2.1 to 31 months. Significant toxicity was observed with this regimen. Ten patients (45%) had leukopenia less than 1,000/microliters, and 11 patients (50%) had thrombocytopenia less than 25,000/microliters. Serum creatinine levels reached greater than 2.0 in 14% of patients. Seven patients (32%) had severe nausea and vomiting. VP-16, cis-platin appears to be an active combination in HD; however, their combined activity is only marginally better than reported single-agent activity for VP-16 in the doses and schedule used. Further studies of related combinations in HD are currently under evaluation by the CALGB.
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PMID:Phase II trial of etoposide and cis-diaminodichloro-platinum in patients with refractory and relapsed Hodgkin's disease: Cancer and Leukemia Group B (CALGB) Study 8353. 232 62


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