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)

Harringtonine, homoharringtonine, deoxyharringtonine and isoharringtonine isolated from Cephalotaxus plant are the esters of cephalotaxine with significant inhibitory activity against P-388 leukemia. In this investigation seventeen new esters of cephalotaxine type alkaloids have been synthesized. Preliminary pharmacological examination showed that compounds 1, 2, 2 + 3, 6 and 8 showed similar antileukemic activity as homoharringtonine. Compounds 4, 5, 15 and 16 showed moderate inhibitory activity. Some structure activity correlations of these esters were discussed.
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PMID:[Studies on the alkaloids of Cephalotaxus. IX. Semi-synthesis of cephalotaxine esters and their anti-leukemic activity]. 141 82

Homoharringtonine (HHT) is a cephalotaxine alkaloid with reported efficacy in acute myelogenous leukemia (AML). In a phase II trial, we evaluated HHT 5 mg/m2 by continuous infusion daily for 9 days in patients with relapsed or refractory acute leukemia and blastic phase of chronic myelogenous leukemia (BLCML). Sixty-six patients were entered. There were 40 males and 26 females with a median age of 41 years (range 15-81). Of 43 patients with relapsed AML, seven achieved a complete remission (16%, 95% confidence interval 5%-27%). Although 11 patients with AML primarily resistant to an anthracycline/cytarabine combination did not respond, two of three patients primarily resistant to low-dose cytarabine achieved complete remission. No patients with acute lymphoblastic leukemia, biphenotypic leukemia, or BLCML responded. Hypotension during the administration of HHT was the most difficult toxicity encountered, requiring multiple interruptions of therapy in several patients and the administration of intravenous saline. Fluid retention and weight gain occurred in 29% of patients. Transient asymptomatic hyperglycemia was observed in 63% of patients. Other toxicity was mild and included nausea and vomiting, diarrhea, mucositis, hepatic dysfunction, and cardiac arrhythmias. As expected, severe myelosuppression occurred in all patients. HHT is well tolerated, but with unique problems associated with administration. It has demonstrable efficacy in pre-treated patients with AML, but its role in the treatment of this disease remains to be defined.
Leukemia 1992 Nov
PMID:Homoharringtonine is safe and effective for patients with acute myelogenous leukemia. 143 2

Homoharringtonine (HHT) is one of several cephalotaxine alkaloids that has shown clinical efficacy in patients with acute myelogenous leukemia (AML). In a phase I trial we evaluated cytarabine 100 mg/m2 by continuous infusion daily for 7 days in combination with four dose levels of HHT ranging from 1.5-5 mg/m2 by continuous infusion daily for 7 days to see if an effective regimen could be developed. Twenty-two patients with relapsed and/or primary refractory AML were treated. Seventeen males and five females were treated, with a median age of 40 years (range 19-63). There were five remissions in 14 patients with relapsed AML and none of eight responders in patients with primary refractory AML. None of the three patients treated at 1.5 mg/m2 dose level of HHT responded. Of three patients treated at the 3 mg/m2 dose level, there was one complete remission. At both 4 mg/m2 and 5 mg/m2, two of eight patients achieved complete remission. Four of the five remissions occurred in patients with acute promyelocytic leukemia. Drug induced pancytopenia was universal, and hypotension and fluid retention were more common at the higher dose levels. Other toxicity was mild and included nausea, vomiting, diarrhea, and mucositis. No significant hepatic, renal, or cardiac toxicity was seen. We conclude that the dose of HHT 4 mg/m2 for 7 days by continuous infusion in combination with cytarabine is safe for patients with AML; and this combination is appropriate for a phase II evaluation.
Leukemia 1992 Nov
PMID:Homoharringtonine in combination with cytarabine for patients with acute myelogenous leukemia. 143 3

Homoharringtonine is one of a group of cephalotaxine esters reported by the Chinese to have significant antitumor efficacy, with particularly good activity in human leukemias. Preclinical antitumor activity against P388 leukemia, colon 38 carcinoma, and mammary carcinoma led to phase I trials which are currently nearing completion in this country. The phase I study reported here used a single infusion of homoharringtonine over 90 minutes given every 21 days. Dose-related and life-threatening hypotension, without significant myelosuppression, was the dose-limiting toxic effect. The mechanism of hypotension is not understood but it is not related to cardiac arrhythmias. Myelosuppression was not seen regularly. We do not recommend this schedule for phase II trials.
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PMID:Phase I trial of homoharringtonine. 688 57

Homoharringtonine and harringtonine are esters of cephalotaxine and are naturally occurring alkaloids in certain coniferous trees in China. These compounds have been shown to have activity against certain types of leukemia in cell cultures, experimental animals, and initial clinical trials in China, and will undergo Phase I trials in several institutions. A gas chromatographic mass spectrometric technique was developed for the quantification of both drugs in serum. One drug serves as internal standard for the other. The drugs are extracted from serum with dichloromethane and are quantified by monitoring the protonated molecular ions of the trimethylsilyl derivatives obtained by chemical ionization (methane). Masses monitored are: m/z = 690 for homoharringtonine and m/z = 676 for harringtonine. Detection limit: 10 ng ml-1 (20 nmol); reproducibility: 1.6-15.0% in the 0-200 ng ml-1 range. Serum levels of harringtonine reached 145 ng mg-1 upon intraperitoneal injection of 3 mg kg-1 in BDF-3 mice.
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PMID:Quantification of homoharringtonine and harringtonine in serum by chemical ionization mass spectrometry. 716 86

Homoharringtonine (HHT) is a cephalotaxine alkaloid that showed clinical efficacy in the chronic phase of chronic myeloid leukemia (Ph1+CML). As a single agent, it resulted in effectively controlling leukocytosis and in producing sporadic karyotypic conversions; its clinical use in combination with interferon (IFN-alpha) for the treatment of CML could thus be considered. In this study we evaluated the growth inhibition and the induction of apoptosis determined by HHT alone and in combination with IFN-alpha and cytosine arabinoside (Ara-C) on normal and CML (both in chronic, CML-CP and in blastic phase; CML-BP) hematopoietic progenitors. HHT is able to determine a dose-dependent cell growth inhibition; evaluation of cytotoxic activity on semisolid cultures showed an activity significantly higher on CML-CP than on normal cells (P = 0.02 for HHT 50 ng/ml and P = 0.01 for HHT 200 ng/ml). HHT exerted a synergistic effect with IFN-alpha, Ara-C and IFN-alpha + Ara-C in inhibiting CML-CP colony growth; the same activity was demonstrated by the combination of HHT with Ara-C and by the triple combination, but not by HHT + IFN-alpha, on normal myeloid progenitors. The triple combination only was able to exert a synergistic effect in CML-BP. The induction of apoptosis resulted HHT dose-dependent in CML-CP and normals; at higher drug concentrations (100-200-1000 ng/ml), HHT induced a significant increase of apoptotic cells (for normals: P = 0.04, P = 0.02 and P = 0.04; for CML-CP: P = 0.01, P = 0.01 and P = 0.04, respectively); no significant changes were observed in CML-BP. In conclusion, the differences in cytotoxic effect and apoptosis induction observed, depending on the various phases of CML, add experimental evidence to the different clinical results between the chronic phase, where the clone is responsive to HHT, and the acute phase, where the drug is ineffective. The in vitro synergism of HHT with Ara-C and IFN-alpha in CML-CP suggests further evaluation in the clinical setting.
Leukemia 1997 May
PMID:Effects of homoharringtonine alone and in combination with alpha interferon and cytosine arabinoside on 'in vitro' growth and induction of apoptosis in chronic myeloid leukemia and normal hematopoietic progenitors. 918 Feb 82

Harringtonine (HT), homoharringtonine (HHT) and isoharringtonine (IHT) are cephalotaxine alkaloids with anticancer activities which were isolated from Cephalotaxus hainanensis indigenous to China. Since the 1970s, HT and HHT have been developed as effective anticancer drugs in China and have been used widely in the treatment of acute nonlymphoid leukemia and chronic granulocyte leukemia. Although IHT has the advantage of low toxicity, it has not been developed as an anticancer drug because of its very low content in the plant. The cell apoptosis induced by isoharringtonine was investigated in human acute promyelocytic leukemia HL-60 cells by agarose gel electrophoresis of DNA, flow cytometry and transmission electron microscopy. In these experiments IHT showed significant and rapid apoptotic inductive effect on HL-60 cells in both concentration- and time-dependent fashion. The characteristic apoptosis-related features could be seen in IHT treated HL-60 cells. Transmission electron microscopy of IHT treated HL-60 cells displayed chromatin condensation and aggregation under the nuclear membrane, nuclear fragmentation and apoptosis body formation. Typical DNA ladder in agarose gel electrophoresis and pre-G1 peak in flow cytometric analysis were also observed in the cells exposed to IHT. The apoptotic rate could reach 43.8% in the HL-60 cells treated for 120 minutes with IHT 10(-7) mol.L-1. The cytotoxicity of IHT paralleled with cell apoptosis indicating that the anticancer activity of IHT results from the induction of apoptosis. These results are important impetus for further research and development of IHT as an anticancer agent.
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PMID:[Isoharringtonine induces apoptosis in human leukemia HL-60 cell]. 1201 8

There is considerable interest among basic and clinical researchers in novel drugs with activity against leukemia. The vast history of experience of traditional Chinese medicine (TCM) with medicinal plants may facilitate the identification of novel antileukemic compounds. In the present investigation, we tested 22 drugs for their activity toward CCRF-CEM cell lines: artesunate, artemisinin, baicalein, baicalin, berberine, bufalin, cantharidin, cephalotaxine, curcumin, daidzein, daidzin, diallyl disulfide, ginsenoside Rh2, glycyrrhizic acid, isonardosinon, homoharringtonine, nardosinon, nardofuran, puerarin, quercetin, tannic acid, and tetrahydronardosinon. As compounds from folk medicinal remedies are sometimes looked upon as alternative medicine with some hesitation or criticism, we investigated only chemically pure compounds and tested the drugs independently in two different laboratories in Germany and Australia. We used CCRF-CEM parental cells and doxorubicin-selected P-glycoprotein (P-gp)/MDR1-expressing CEM/ADR5000, vinblastine-selected P-gp/MDR1-expressing CEM/VLB(100), and epirubicin-selected multidrug resistance-related protein 1 (MRP1)-expressing CEM/E1000 sublines thereof. While CEM/ADR5000, CEM/VLB(100), and CEM/E1000 cells were highly resistant to the corresponding selecting agents, no or only minimal degrees of cross-resistance were observed to TCM drugs in both growth inhibition assay and MTT assay (range from 0.4- to 8-fold). Homoharringtonine, artesunate, and bufalin were most active among this panel of compounds. As shown by flow cytometry, artesunate significantly increased daunorubicin accumulation in CEM/E1000 cells, but not in CEM/VLB(100) or CCRF-CEM parental cells. Bufalin caused a small, but significant increase in daunorubicin accumulation in CEM/VLB(100) and CEM/E1000 cells. As artesunate and bufalin showed both antileukemic activity if applied alone and modulation activity in combination with daunorubicin in multidrug-resistant (MDR) cells, these two drugs may be suitable for novel combination treatment regimens to improve leukemia cell killing.
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PMID:Activity of drugs from traditional Chinese medicine toward sensitive and MDR1- or MRP1-overexpressing multidrug-resistant human CCRF-CEM leukemia cells. 1206 12

Deoxyharringtonine (1) is among the most potent of the anti-leukemia alkaloids isolated from the Cephalotaxus genus. A convergent total synthesis of (-)-1 is reported, involving novel synthetic methods and strategies that include (1) the strain-release rearrangement of N-aryl-2-vinylaziridines for [3]benzazepine synthesis, (2) a vinylogous amide acylation-cycloaddition cascade for spiro-pyrrolidine construction, and (3) efficient acylation of the cephalotaxine core by alpha-(beta-lactone)carboxylic acid derivatives to access the biologically active cephalotaxus esters. These innovations should allow rapid access not only to other Cephalotaxus alkaloids but also to non-natural analogues of potential therapeutic utility.
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PMID:Strain-release rearrangement of N-vinyl-2-arylaziridines. Total synthesis of the anti-leukemia alkaloid (-)-deoxyharringtonine. 1689 94

The Cephalotaxus genus belongs to the Cephalotaxaceae family of conifers. Over the past decades it has proved to be a fruitful source of interesting natural products, especially alkaloids (cephalotaxine esters) and terpenoids (abietanes, troponoids), which often display medicinal properties, especially in the anticancer area. Homoharringtonine is active against some orphan leukaemia and is nowadays approaching marketability. A phytochemical update will be provided and the total synthesis of alkaloids and terpenoids will be discussed in detail.
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PMID:Natural products from Cephalotaxus sp.: chemical diversity and synthetic aspects. 2271 32


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