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)

Chlorozotocin is a chloroethyl nitrosourea with a glucose carrier that has curative activity for the murine L1210 leukemia, but is nonmyelosuppressive in mice. To determine the mechanism for this unique property of reduced bone marrow toxicity, comparative studies were conducted with chlorozotocin and CCNU, a myelotoxic chloroethyl nitrosourea. Suspensions of L1210 leukemia and murine bone marrow cells were incubated for 2 h with 0.1 mM [(14)C]-chloroethyl chlorozotocin or CCNU. Chlorozotocin demonstrated a fourfold increased covalent binding of the chloroethyl group to L1210 nuclei when compared to equimolar CCNU. Chlorozotocin alkylation of L1210 cells resulted in the binding of 57 pmol of [(14)C]ethyl group/mg of DNA, which represented a 2.3-fold increased alkylation when compared to CCNU. In marked contrast, the binding of the chloroethyl group to bone marrow nuclei was equivalent for both drugs. In addition, chlorozotocin alkylation of murine bone marrow DNA, 45 pmol of [(14)C]ethyl group/mg of DNA, was equivalent to that of CCNU. The ratio of L1210:bone marrow DNA alkylation was 1.3 for chlorozotocin compared to 0.6 for CCNU. The intracellular carbamoylation of L1210 and bone marrow protein by CCNU was 400- to 600-fold greater than that produced by chlorozotocin. After a 2-h exposure to 0.1, 0.05, or 0.01 mM drug, both chlorozotocin and CCNU produced a reduction in the cloning efficiency of L1210 cells that was dose dependent. However, chlorozotocin was significantly more cytotoxic than CCNU at all three molar concentrations (P < 0.01). Chlorozotocin, 0.1 mM, reduced L1210 DNA synthesis to 1% of control by 48 h, in contrast to 16% with equimolar CCNU (P < 0.01). In mice bearing 10(5) L1210 cells, chlorozotocin produced its optimal antitumor activity (332% increased life span [ILS]) at doses of 48-64 mumol/kg, with >50% indefinite survivors. In contrast, CCNU at the same molar doses resulted in only a 191% ILS; a CCNU dose of 128 mumol/kg was required for comparable optimal L1210 antitumor activity, 413% ILS. On a molar basis, the dose of chlorozotocin that produced optimal in vivo L1210 antitumor activity was one-third to one-half that of CCNU. Chlorozotocin, unlike CCNU, produced no murine bone marrow toxicity at its optimal therapeutic dose. This unique combination of antitumor activity without myelosuppression can be correlated with the advantageous ratio of L1210:bone marrow in vitro DNA alkylation by chlorozotocin (1.3) as compared to equimolar CCNU (0.6).
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PMID:Chlorozotocin. Mechanism of reduced bone marrow toxicity in mice. 15 33

The newly synthesized nitrosoureas 1-(2-chloroethyl)-1-nitroso-3-(methylenecarboxamido)-urea (Acetamido-CNU), 1-(2-chloroethyl)-1-nitroso-3-(4-morpholino)-urea (Morpholino-CNU), 1-(2-chloroethyl)-1-nitroso-3-(1-piperidino)-urea (Piperidino-CNU), and 2-[3-(2-chloroethyl)-3-nitrosoureido]-ethylmethanesulfonate (Ethylmethanesulfonato-CNU) were compared in their chemotherapeutic activity against preterminal rat leukemia L 5222 with BCNU, CCNU, MeCCNU, Chlorozotocin, and Hydroxyethyl-CNU. With respect to the dose range effecting a median survival time of more than 90 days, MeCCNU was superior to the other substances. Chlorozotocin, on the other hand, was the only substance which achieved no cures in this experimental arrangement. From the four newly introduced substances the water-soluble substances Acetamido-CNU and Morpholino-CNU were approximately comparable to CCNU with regard to the dose range effecting a median survival time of greater than 90 days. Piperidino-CNU and Ethylmethanesulfonato-CNU also effected cures; however, only Piperidino-CNU in one dosage effected a median survival time of greater than 90 days.
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PMID:Examination of four newly synthesized 2-chloroethylnitrosoureas in comparison with BCNU, CCNU, MeCCNU, chlorozotocin and hydroxyethyl-CNU in preterminal rat leukemia L 5222. 15 9

Two hundred and twenty-seven children with recurrent acute lymphoblastic leukemia were treated with various combinations of vincristine, prednisone, cyclophosphamide and L-asparaginase in an approach to the induction of remission. The combination of L-asparaginase 1,000 mu/kg iv q.d. x 10, vincristine 2.0 mg/m2iv q.w. x 4 and prednisone 40 mg/m2 p.o.q.d. x 28 days was found to be highly effective. The incidence of remission was 73%. No significant improvement was achieved when cyclophosphamide was added to this regimen. Various combinations of cytosine arabinoside, cyclophosphamide, vincristine, prednisone, BCNU or CCNU failed to maintain remission duration for more than two or three months. Neither BCNU nor CCNU prevented the development of CNS leukemia.
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PMID:Vincristine, prednisone and L-asparaginase in the induction of remission in children with acute lymphoblastic leukemia following relapse. 27 45

In May 1972, the Cancer and Leukemia Group B initiated a randomized study comparing the effectiveness of CCNU and methyl-CCNU in patients with advanced malignant lymphomas, including Hodgkin's disease (HD), lymphosarcoma (LYS) and reticulum cell sarcoma (RCS). A single dose of 100 mg/m2 of CCNU or 150 mg/m2 of methyl-CCNU was given orally every 6 weeks. In patients with leukopenia or thrombocytopenia, due to prior treatment, this dose was reduced to 70 mg/m2 of CCNU and 100 gm/m2 of methyl-CCNU. Of 109 evaluable patients, 60 received CCNU and 49 received methyl-CCNU. Response rates (complete and partial) to CCNU and methyl-CCNU were respectively 42% (14/33) and 15% (3/20) in HD, 21% (3/14) and 21% (3/14) in LYS, 15% (2/13) and 27% (4/15) in RCS. Responses to methyl-CCNU, but not to CCNU, were seen only in patients who developed significant hematologic toxicity. Responses to both drugs were generally of short duration due to the advanced stage of the disease. Renal, hepatic or neurological toxicity was not observed. In conclusion, CCNU proved to be superior to methyl-CCNU for the treatment of advanced HD. CCNU was also observed to be of higher activity in Hodgkin's than in non-Hodgkin's lymphomas.
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PMID:Comparison of methyl-CCNU and CCNU in patients with advanced forms of Hodgkin's disease, lymphosarcoma nad reticulum cell sarcoma. 34 94

A novel nitrosourea derivative, methyl-6-[[[(2-chloroethyl)nitrosoamino]carbonyl]-amino]-6-deoxy-alpha-D-glucopyranoside (MCNU), is a water-soluble compound in which a methoxyl group is attached to the C-1 position and an N-(2-chloroethyl)-N-nitrosoureido group is attached to the C-6 position of the glucose moiety. MCNU exhibited a marked life-prolongation or growth-inhibitory effect against mouse L1210 leukemia, adenocarcinoma 755, Nakahara-Fukuoka sarcoma, Lewis lung carcinoma, and B16 melanoma. Ip, oral, or iv administration of MCNU was markedly effective against L1210 leukemia, and the therapeutic ratio by ip administration was larger than that of chlorozotocin or CCNU. The life-prolongation effect of MCNU against established Lewis lung carcinoma was similar to that of methyl-CCNU. The bone marrow toxicity of MCNU was less than that of CCNU but considerably more than that of chlorozotocin.
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PMID:Biologic activity of MCNU: a new antitumor agent. 46 55

Four new nitrosourea derivatives represent an appreciable progress in the treatment and cure of L1210 leukemia. Their therapeutic index is higher than that of CCNU and MeCCNU. Of these compounds, RFCNU may prove the most promising, as its therapeutic index is the highest of those for all the four compounds studied; moreover, unlike the other products, it is not immunosuppressive, whether administered before or after the antigen.
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PMID:The oncostatic and immunosuppressive action of new nitrosourea derivatives containing sugar radicals. 122 17

Transplantable adenocarcinomas of the colon in mice have been developed from primary tumors induced by 1,2-dimethylhydrazine. Two such transplant lines, MAC-13 and MAC-15, have been used to assess the possible value of this type of tumor in chemotherapy screening. A protocol has been established and 11 standard drugs were tested against the two lines. Both tumors show sensitivity which is remarkably similar to that of human large bowel cancer, and MAC-13 would have correctly predicted the activity in man for ten of the 11 drugs. Quantitatively, CCNU, methyl-CCNU, and cyclophamide were the most effective drugs. A comparison of the predictive efficiencies of L1210 leukemia, B16 melanoma, and these new tumors as screening systems for colorectal cancer is made and discussed.
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PMID:Chemotherapy of transplanted adenocarcinomas of the colon in mice. 122 93

The ability of DNA repair inhibitors to potentiate alkylating agent cytotoxicity was explored with PD 128763, a dihydroisoquinolinone known to effectively inhibit poly(ADP-ribose) synthetase. The cytotoxic activity of streptozotocin in L1210 leukemia cells was maximally potentiated (7-fold decrease in IC50) under conditions of 24 hr exposure to PD 128763 following treatment with the alkylating agent for 1 hr. Similar treatment conditions resulted in a much greater effect (36-fold enhancement in activity) for the 2-nitroimidazole RSU 1069. In contrast, 3-aminobenzamide was only weakly effective at enhancing activity of either streptozotocin or RSU 1069 (2-3 fold potentiation). However, PD 128763 was ineffective at potentiating the cytotoxicity of the bifunctional alkylating agents carmustine (BCNU) and lomustine (CCNU). Our results are consistent with a role for (poly-ADP) ribosylation in the repair of monofunctional alkylating agent damage. This study supports further exploration of the combination of PD 128763 and RSU 1069 as a potentially useful chemotherapeutic regimen.
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PMID:Enhancement of alkylating agent activity in vitro by PD 128763, a potent poly(ADP-ribose) synthetase inhibitor. 153 Dec 21

One hundred twenty-five assessable patients with advanced-stage Hodgkin's disease were randomized to receive mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) or MOPP alternating with lomustine (CCNU), doxorubicin, bleomycin, and streptozocin (CABS). The median follow-up is 7.7 years. The complete response rate was 60 of 66 MOPP-treated patients (91%) and 54 of 59 MOPP/CABS-treated patients (92%) (difference not significant). The level of the disease-free survival curve at longest follow-up is 65% for MOPP-treated patients and 72% for MOPP/CABS-treated patients (difference not significant). The overall survival at 12 years is projected at 68% for MOPP-treated patients and 54% for MOPP/CABS-treated patients (difference not significant). Thus, there were no significant differences in efficacy between MOPP and MOPP/CABS. However, MOPP/CABS was more emetogenic than MOPP, and four MOPP/CABS-treated patients went on to develop secondary acute leukemia. No MOPP-treated patients developed leukemia. High initial erythrocyte sedimentation rate (ESR) and high platelet counts adversely affected treatment outcome. MOPP-treated patients who received greater than 81% of the projected dose intensity of vincristine over the first three cycles had significantly improved disease-free survival rates over those receiving less than 81%. MOPP/CABS-treated patients who received greater than 82% of the projected dose intensity of vincristine had significantly better overall survival than those who received less than 82%. Disease-free survival on both arms was significantly better in patients who received greater than 84% of the projected dose intensity of all agents. The effect of dose intensity was particularly apparent in patients with poor prognostic factors where those who received greater than 84% of the projected dose intensity of all agents had significantly improved disease-free and overall survival.
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PMID:Treatment of advanced-stage Hodgkin's disease: alternating noncrossresistant MOPP/CABS is not superior to MOPP. 171 36

Synthesis of 2,6-Bis[bis(2-chloroethyl) amino]-4,8-dipiperidinopyrimido[5,4-d] pyrimidine, a derivative of dipyridamole, was carried out by treating dipyridamole with thionyl chloride. Cytotoxic activity of this compound was assessed using cultured P388 leukaemia cells and HeLa cells. The compound inhibited the colony-forming ability of HeLa cells and showed a cytotoxicity on P388 cells comparable to that of other alkylating drugs (chlorambucil and CCNU).
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PMID:Synthesis and cytotoxic activity of a new alkylating derivative of dipyridamole. 201 74


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