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)

Using flow cytometry and immunocytochemistry, we investigated the reactivities of two different murine monoclonal antibodies (MAbs), MRK 16 and MRK 20, specific to adriamycin-resistant K562 cells (K562/ADM) with peripheral human mononuclear cells (MNC) (mainly blastic cells and lymphocytes) from 31 patients with leukaemia or malignant lymphoma. Reactivity with MRK 16 MAb was observed in five cases and reactivity with MRK 20 MAb in 18 cases. The cases were divided into three groups according to their reactivity patterns: group I, only the proportion of MRK 16-positive cells was increased; group II, only the proportion of MRK 20-positive cells was increased; group III, both MRK 16-and MRK 20-positive cells were increased. Some cases reflected the prior administration of adriamycin, vincristine, vinblastine and VP-16, which are known to induce P-glycoprotein expression. Expression of Mr 85,000 protein was observed more frequently than that of P-glycoprotein in leukaemia and malignant lymphoma, and this was not associated with either the total dose or period of administration of anticancer drugs. The expression of Mr 85,000 protein recognised by MRK 20 was further confirmed by Western blot analysis.
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PMID:High-level expression of MRK 16 and MRK 20 murine monoclonal antibody-define proteins (170,000-180,000 P-glycoprotein and 85,000 protein) in leukaemias and malignant lymphomas. 257 70

Forty cultured human leukemia and lymphoma cell lines never exposed to anticancer agents in culture, apart from doxorubicin (ADM)-resistant K562/ADM, were examined for reactivity with a monoclonal antibody, MRK16 in F(ab')2 form [MRK16-F(ab')2], which recognizes P-glycoprotein (P-gp). The relative resistance index to various drugs was calculated by dividing the 50% growth inhibitory concentration (IC50) of the test cell line by IC50 of K562, which was the negative control in the antibody experiment. MRK16-F(ab')2 reacted with four cell lines, K562/ADM, KYO-1, HEL and CMK, which had relative resistance index values of 2 or more to vincristine (VCR), vindesine, vinblastine, ADM, daunorubicin, mitoxantrone (MIT), etoposide (VP-16) and actinomycin-D (ACT-D). The level of resistance to VCR and ADM in these cell lines decreased significantly in the presence of 10 microM verapamil in vitro. Significant expression of mRNA of P-gp gene was also detected in K562/ADM, KYO-1 and HEL. MRK16-F(ab')2 did not react with 36 other cell lines. Among them, three cell lines, PL-21, P31/FUJ and KOPM-28, had relative resistance index values of 2 or more to anthracyclines, MIT and VP-16, but not to vinca alkaloids or ACT-D. The level of ADM-resistance in these cell lines did not decrease significantly in the presence of 10 microM verapamil. Five cell lines, ATL-1K, HL-60, KMOE-2, ML-1 and U266, had relative resistance index values of 2 or more to some of the drugs, but not to the others, and 19 other cell lines did not. These results indicate that the reactivity of MRK16-F(ab')2 correlates with a relative resistance index of 2 or more to all these drugs in cultured human leukemia and lymphoma cell lines.
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PMID:Multidrug resistance in cultured human leukemia and lymphoma cell lines detected by a monoclonal antibody, MRK16. 257 8

The effect of verapamil (calcium influx blocker) on adriamycin-induced cytotoxicity against sensitive and resistant subline of K 562 acute myelogenous human leukemia cells has been evaluated. Verapamil by itself at a concentration of 0.5 microgram/ml did not affect the cell growth. It was found that the nontoxic concentration of verapamil moderately enhanced adriamycin cytotoxicity against K 562 cells, showing enhancement ratio of 1.3-1.4 according to the schedule used. A significant enhancement of adriamycin cytotoxicity (enhancement ratio of 5.8) was observed when verapamil and adriamycin were administered simultaneously against resistant subline of K 562/ADM cells. The results obtained give grounds to assume that verapamil could be used to overcome drug resistance in tumor cells.
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PMID:Effect of calcium influx blocker verapamil on adriamycin-induced cytotoxicity in leukemia cells in vitro. 263 1

Harringtonine showed cross resistance in adriamycin-resistant murine leukemia P388 (P388/ADM) and human leukemia K562 (K562/ADM) cells. The relative resistance of the P388/ADM and K562/ADM cells to harringtonine was about 7 and 40, respectively. Calcium influx blockers, diltiazem and the biscoclaurine alkaloid cepharanthine enhanced the cytotoxicity of harringtonine in P388/ADM and K562/ADM cells. The extent of enhancement was different for the two drugs, and up to a 9- to 10-fold increase in harringtonine cytotoxicity occurred in P388/ADM cells, and 14- to 22-fold enhancement in K562/ADM cells with diltiazem or cepharanthine. Harringtonine resistance of P388/ADM was circumvented completely, and the resistance of K562/ADM was circumvented partially, by diltiazem or cepharanthine. The mechanism of enhanced cytotoxicity by diltiazem and cepharanthine is probably inhibition of active efflux of harringtonine in P388/ADM and K562/ADM cells.
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PMID:Potentiation of harringtonine cytotoxicity by calcium antagonist diltiazem and biscoclaurine alkaloid cepharanthine in adriamycin-resistant P388 murine leukemia and K562 human leukemia cells. 275 76

Structures of three antioxidant isoflavonoids isolated from the cultured broth of Streptomyces sp. OH-1049 were shown to be 4',7,8-trihydroxyisoflavone (1), 3',4',7-trihydroxyisoflavone (2) and 8-chloro-3',4',5,7-tetrahydroxyisoflavone (3), respectively. Among them, 3 is a novel isoflavonoid possessing a chlorine atom in the molecule. Compound 1 was synthesized and its antitumor activities were tested against IMC carcinoma, S180, P388 leukemia and P388/ADM leukemia in vivo. As a result, 1 showed 139% increase in life span (ILS) against S180 bearing mice whereas it showed slight or no ILS against IMC carcinoma, P388 leukemia and P388/ADM leukemia bearing mice.
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PMID:Structural study of isoflavonoids possessing antioxidant activity isolated from the fermentation broth of Streptomyces sp. 279 89

The authors have synthesized 7-O-(2,6-dideoxy-2-fluoro-alpha-L-talopyranosyl) adriamycinone (FT-ADM) which exhibited strong antitumour activity and weak toxicity. These characteristics of FT-ADM are partly due to the presence of a 2'-fluoro atom which strengthens the glycoside bond. FT-ADM, however, is sparingly soluble in water because of lack of the 3'-amino group of adriamycin. To increase the solubility of FT-ADM, a hydrophilic group was added at the 14-OH group. Then, the 14-hemisuccinate, 14-hemiglutarate, 14-hemiadipiate, 14-hemipimelate and 14-hemisuberate derivatives of FT-ADM were synthesized. Among them, the 14-hemipimelate derivative (FAD-104) was selected for further development because of its potent antitumour activity and weak toxicity. When drugs were injected intraperitoneally every day from day 1 to 9, FAD-104 showed an apparently stronger antitumour effect against mouse L-1210 leukaemia than adriamycin with lower toxicities. FAD-104 was also more effective than adriamycin on L-1210 using other administration schedules. A characteristic feature is that FAD-104 is effective over a very broad range, which will be advantageous for safe clinical use. FAD-104 also showed marked antitumour effect against L-1210 when it was injected intravenously either once on day 1 or three times on days 1, 5 and 9. Thus, FAD-104 may be a more potent antitumour anthracycline than adriamycin.
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PMID:Antitumour activity of new semi-synthetic anthracyclines containing fluorotalopyranose. 324 Jul 3

In this article, the clinical effects of rH-TNF on various cancer patients and the mechanism of self-induction of defense against rH-TNF cytotoxicity in tumor cells and the counter measures against this are reviewed. 1) Clinical effects of rH-TNF Intratumoral administration of rH-TNF was performed in 7 patients and clinical efficacy (PR + MR) was observed in 3/7 (42.9%). Also a reduction of leukemia cells in peripheral blood was observed in all 4 leukemia patients following intravenous (i.v.) administration of rH-TNF. Furthermore, in 2 multiple myeloma patients, the myeloma protein and plasma cells in bone marrow were reduced by i.v. administration of rH-TNF. 2) Self-induction of defense against rH-TNF cytotoxicity Investigation of the effect of TNF on RNA and protein synthesis by tumorigenic and normal cell lines showed that their synthesis in tumor cells was increased at 12 h and peaked at 24 h of incubation with TNF, while that in normal diploid fibroblast (HEL) cells was apparently unaffected by the presence of TNF. Artificial inhibition of either RNA or protein synthesis by L-M cells, upon addition of Act D or CHI increased the cytotoxic effect of TNF, thus suggesting that the elevated RNA and protein synthesis is related not to the cytotoxic reaction itself but rather to a defense mechanism. Similar incubation of HEL cells with TNF in the presence of either inhibitor resulted in the occurrence of cytotoxicity not observed with TNF alone, thus suggesting the existence of a defense mechanism in normal, TNF-resistant cells which is absent or greatly weakened in tumor cells. 3) Combination therapy of rH-TNF with various anticancer drugs. A synergistic increase in the cytotoxic effects of rH-TNF and anti-cancer drugs was demonstrated in vitro The cytotoxicity of rH-TNF against L-M cells in combination with MMC, ADM, Ara-C, ACD, DM, CDDP, VCR and 5-FU was 4 to 347 times as high as that of rH-TNF alone. These results suggest that combination therapy including rH-TNF and anti-cancer drugs may be of value in the treatment of malignancy in human patients.
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PMID:[Anti-tumor effect of human recombinant TNF]. 329 72

A cultured subline (P388/ADM) of mouse P388 leukemia resistant to doxorubicin, vinblastine, vincristine, dactinomycin, and daunorubicin became sensitive again when treated with noncytotoxic doses of either of two synthetic isoprenoids: N-solanesyl-N,N'-bis(3,4-dimethoxybenzyl)ethylenediamine (SDB-ethylenediamine) and N-(p-methylbenzyl)decaprenylamine X HCI (PMB-decaprenylamine). The isoprenoids also reversed resistance to doxorubicin and vincristine in a cultured vincristine-resistant P388 leukemia subline (P388/VCR). Median lethal doses (LD50) for PMB-decaprenylamine and SDB-ethylenediamine administered ip were 123 and 350 mg/kg against mice, whereas the LD50 for verapamil, another modifier of cellular drug resistance, was about 7.6 mg/kg. In vivo experiments with P388/VCR-bearing mice showed that both SDB-ethylenediamine and verapamil overcame vincristine resistance, but PMB-decaprenylamine showed only slight activity. SDB-ethylenediamine was especially effective, overcoming the vincristine resistance at 1 mg drug/kg. Since the structure of SDB-ethylenediamine resembles that of verapamil, a calcium-blocking agent that overcomes drug resistance, it was checked for calcium-blocking activity. However, calcium channel-blocking activity was not observed with 20 micrograms isoprenoid/ml, whereas calcium channel activity was completely blocked by 1 microgram verapamil/ml.
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PMID:Overcoming drug resistance in cancer cells with synthetic isoprenoids. 345 80

The calcium channel blockers verapamil, diltiazem, nicardipine, and niludipine potentiated the antitumor activities of mitotic poison antitumor agents, such as vincristine, vinblastine, vindesine, VP16-213, and taxol in P388 leukemia cells resistant to vincristine. The potentiating effect was generally dependent on the extent of cross-resistance seen in the cell line for these drugs. Calcium channel blockers also potentiate the antitumor activities of several DNA-interacting drugs, such as adriamycin, THP-adriamycin, daunomycin, aclacinomycin A, mitomycin C, actinomycin D, mitoxantrone, and nogalamycin derivatives in P388 leukemia resistant to adriamycin. Greater potentiation was observed for those antitumor agents to which the ADM-resistant cell line had become markedly cross-resistant, with the exception of the nogalamycin derivatives. Only a two-fold enhancement was observed for mitomycin C and aclacinomycin, as the cell line was only weakly cross-resistant to these agents. These results suggest the potential for therapeutic gain through the use of calcium channel blockers in combination with classic chemotherapeutic agents.
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PMID:Potentiation of antitumor agents by calcium channel blockers with special reference to cross-resistance patterns. 400 44

(2''R)-4'-O-Tetrahydropyranyladriamycin (THP) is a new derivative of doxorubicin (adriamycin, ADM). The concentrations of THP and ADM required to inhibit by 50% the growth of a cultured L1210 cells was 0.003 microgram/ml and 0.016 microgram/ml, respectively. Various therapeutic designs of combinations of THP with other antitumor agents were investigated in vivo using the L1210 murine leukemia. The combination of THP with cytosine arabinoside (Ara-C), cyclocytidine hydrochloride (Cyclo-C), 6-mercaptopurine (6-MP) and cyclophosphamide (EX) showed a great effectiveness following daily intraperitoneal treatment from days 1 to 10. High therapeutic effects were also obtained with the combinations of THP with Ara-C, Cyclo-C, vincristine (VCR) and EX following intravenous combination therapy one day following implantation of L1210 leukemia. Schedule dependency and its therapeutic efficacy of THP were examined. THP showed almost the same antitumor activity on the solid-type sarcoma-180 or solid-type Ehrlich carcinoma as ADM by intraperitoneal or intravenous treatment. THP showed some superior activity to ADM in the advanced stage of L1210 leukemia. High antitumor activity of THP on murine leukemia L1210 has been reported by Tsuruo et al. (Cancer Res. 42: 1462-1467, 1982) and was also confirmed. THP gave many mice cures, especially in the intravenous treatment.
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PMID:Antitumor activities of (2"R)-4'-O-tetrahydropyranyl-adriamycin (THP) and its combination with other antitumor agents on murine tumors. 406 93


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