Intermediate and high-dose ARA-C and m-AMSA (or daunorubicin) as remission and consolidation treatment for patients with relapsed acute leukaemia and lymphoblastic non-Hodgkin lymphoma

27 patients (aged 15-55 years) with relapsed acute myelogenous (AML) and lymphoblastic leukaemia (ALL), and with lymphoblastic non Hodgkin's lymphoma (NHL) have been treated with intermediate dose cytosine arabinoside (AraC, 1 g/m2 q 12 h X 12) and 3 d of m-AMSA (20 patients), 90-115 mg/m2 daily, or daunorubicin (7 patients). 18 of them attained a complete remission (AML 10/14, ALL 3/5, NHL 5/8). 7 patients received consolidation treatment with 1-2 courses comprising 4 d of AraC (3 g/m2 q 12 h X 8) and m-AMSA (90-115 mg/m2) on d 5 of each course. 2 patients underwent allogeneic bone marrow transplantation and 9 received no further treatment after remission induction. In addition to vomiting, fever and conjunctivitis, toxicity in 6 patients included a combination of severe diarrhoea, fever and signs of paralytic ileus. 3 of them died during the pancytopenic phase. The pancytopenic period ranged from 16-25 d (median 21 d) after the remission induction and 14-21 d (median 19 d) after the consolidation course. Median remission duration was 5 months for those patients who received no treatment after remission induction and greater than 9 months (4+ - 16+ months) for the patients who received consolidation courses. Increased dosages of AraC are active in relapsed leukaemia and lymphoma, although optimal dose and schedule are still undetermined.

Enhancement of the DNA breakage and cytotoxic effects of intercalating agents by treatment with sublethal doses of 1-beta-D-arabinofuranosylcytosine or hydroxyurea in L1210 cells

4'-(9-Acridinylamino)methanesulfon-m-anisidide (m-AMSA) and other DNA intercalating agents produce protein-associated DNA strand breaks, the formation of which are mediated by topoisomerase-like chromosomal proteins. As topoisomerases would be expected to be most active during DNA replication, DNA synthesis inhibitors may alter the sensitivity of cellular DNA to intercalator-induced scission. We report that treatment of L1210 cells with 1-beta-D-arabinofuranosylcytosine (ara-C) (0.1 microM) or hydroxyurea (HU) (0.1 mM) for 18 hr resulted in a 2- to 2.4-fold enhancement of m-AMSA-induced protein-associated DNA single-strand breaks and DNA-protein cross-links as measured by alkaline elution. This enhancement was dependent on the duration of ara-C or HU treatment as well as on the concentration of ara-C or HU. Enhancement did not correlate with any alteration in cellular uptake of intercalator or with ara-C- or HU-induced alterations in the DNA synthetic rate. The DNA within nuclei isolated from ara-C- or HU-treated cells also displayed an enhanced susceptibility to m-AMSA-induced scission. There was a correlation between enhanced single-strand break formation and recruitment of cells into S-phase as well as between single-strand break formation and the production of a hypomethylated state of cellular DNA. Concurrent with the enhancement of m-AMSA-induced cellular DNA effects was a synergistic effect on m-AMSA cytotoxicity by ara-C or HU. This enhancement of intercalator effects was also found for the intercalator Adriamycin. We propose that these sublethal concentrations of ara-C and HU alter chromatin structure possibly via DNA hypomethylation and/or altered DNA-histone interactions so that intercalator-induced DNA effects are enhanced. Alternatively, the topoisomerase-like activity involved in intercalator-induced, protein-associated DNA break production may be increased in the nuclei of ara-C- or HU-treated cells.

Chlorpromazine: a potential anticancer agent?

The antipsychotic drug chlorpromazine causes scission of the DNA in PY815 mouse mastocytoma cells or isolated PY815 cell nuclei and the broken DNA reseals when chlorpromazine is removed from nuclei. These properties suggest that chlorpromazine interferes with topoisomerase action as do several other DNA-intercalating anti-cancer drugs. However, protein is not associated with the broken DNA after chlorpromazine treatment suggesting a different mode of action on the topoisomerase. Reasons why chlorpromazine may have potential as anti-cancer agent are considered.

Premature chromosome condensation studies in human leukemia: 5. Prediction of early relapse

Previous reports have suggested that the technique of premature chromosome condensation (PCC) is useful for predicting relapse in patients with acute leukemia. However, these studies involved patients had been in complete remission (CR) for various periods of time and had heterogeneous expectations for relapse. The purpose of this study was to further determine the value of PCC in predicting relapse by examining the PCC characteristics of bone marrow specimens from patients with acute leukemia on a common therapeutic regimen after similar periods in CR. The remission durations after the PCC determinations were compared between patients with high or low proliferative potential indices (PPI, or the fraction of G1 cells in late G1 phase). Of 60 patients studied between two and eight weeks after achieving CR, 14 of the 16 patients exhibiting high PPI values (greater than or equal to 35) have relapsed. The mean time from PCC measurement to relapse was 23 weeks. In contrast, only 19 of the 44 patients exhibiting low PPI values have relapsed, with an estimated mean time to relapse of 68+ weeks. Likewise, of 38 patients studied between nine and 15 weeks of CR, nine of the ten patients exhibiting high PPI values have relapsed (mean time to relapse, 23 weeks), while only 16 of 28 patients with low PPI values have relapsed (estimated mean time to relapse, 54+ weeks). The predictive value of the PCC technique was found to be independent of other prognostic factors for the duration of CR, and it identified those patients within the poor prognostic category with a high likelihood of imminent relapse. While similar trends were observed at later time intervals in CR, the differences in relapse rate between patients with high or low PPI values is not significant. These results confirm the usefulness of the PCC technique in predicting relapse in acute leukemia and could aid in the identification of patients who might benefit by an alteration of therapeutic strategy.

In vivo and in vitro cytogenetic effects of the anti-tumor agent amsacrina (AMSA)

The genotoxic effect of AMSA, an anti-tumor agent, was evaluated using the micronucleus and anaphase-telophase tests. The doses assayed by the in vivo micronucleus test were 1.5, 3 and 6 mg/kg: they are within the range of those used in clinical trials. A significant increase of micronucleated cells (P less than 0.01) was observed in the three assayed doses, with a linear dose response (r 0.98). In the in vitro test, 3 drug concentrations, i.e. 10, 1 and 0.1 microgram/ml, were analyzed with the 2 higher doses. AMSA showed a marked inhibition of cellular replication, but with 0.1 microgram/ml it was possible to determine an increase (P less than 0.01) in aberrations in anaphase-telophase cells. Both studies clearly demonstrate the clastogenic effect of the drug, which should be taken into account when considering its carcinogenic risk.

Quantitative and qualitative effects of m-AMSA (amsacrine) on cellular immune components

The recently developed acridine derivative 4'-[(9-acridinyl)amino] methanesulphon-m-anisidine (m-AMSA) has become one of the preferred agents in the management of acute leukaemia but little is known of its effects on cellular immune components. We evaluated the qualitative and quantitative effects of m-AMSA on immune cell numbers and function, during both the leucopenic and myelorestorative phases, following intermittent high-dose therapy. Cell-mediated and inflammatory responses were depressed in the treated animals during the leucopenic phase but restoration of immune capability paralleled the recovery of circulating leucocyte numbers. Additionally, m-AMSA displayed unexpected immunomodulatory features: thymus-dependent antibody and delayed-type hypersensitivity responses were actually increased, suggesting the potential of m-AMSA as an immunoregulator in clinical and experimental studies.

Comparison of the mutagenic and clastogenic activity of amsacrine and other DNA-intercalating drugs in cultured V79 Chinese hamster cells

The acridine derivative amsacrine (m-AMSA) is used clinically for the treatment of acute leukemias. The mutagenic activity of this drug has been evaluated at the 6-thioguanine (6-TG) and ouabain resistance loci in cultured Chinese hamster fibroblasts (V79-171b cell line). m-AMSA was found to have weak but significant mutagenic activity at the 6-TG but not at the ouabain resistance locus, after either 1- or 45-hr exposures at concentrations causing up to 90% cell kill. Two other intercalating agents with antitumor activity, Adriamycin and actinomycin D, provided essentially identical results. All three drugs were potent inducers of micronuclei in V79-171b cells, indicating high clastogenic activity. For these intercalating agents, the yield of 6-TG-resistant mutants was approximately 100-fold lower than that for ethyl methanesulfonate after exposures causing equivalent toxicity or equivalent chromosome breakage. The acridine half-mustard ICR-191 resembled ethyl methanesulfonate rather than the other intercalating agents in providing a high yield of 6-TG-resistant mutants relative to its clastogenic activity. The tumor-inactive intercalator 9-aminoacridine demonstrated only low clastogenic activity with a lack of significant mutagenic activity at toxic concentrations. These results suggest that, for m-AMSA, Adriamycin, and actinomycin D, both cell killing and mutagenesis could be direct consequences of chromosome breakage, while 9-aminoacridine may kill cells by a different mechanism. In view of its mutagenic and clastogenic activity at clinically achievable exposures and the similarity of its genotoxic properties to Adriamycin, m-AMSA should be considered a potential carcinogen.

Glutathione metabolism as a determinant of therapeutic efficacy: a review

Glutathione, as the chief nonprotein intracellular sulfhydryl, affects the efficacy and interactions of a variety of antineoplastic interventions, mainly through nucleophilic thioether formation or oxidation-reduction reactions. Thus, glutathione plays a role in the detoxification and repair of cellular injury by such diverse agents as mechlorethamine, melphalan, cyclophosphamide, nitrosoureas, 6-thiopurine, 4'-(9-acridinylamino)methanesulfon-m-anisidide, the quinone antibiotics (including Adriamycin, daunorubicin, and mitomycin C), the sesquiterpene lactones (such as vernolepin), and other sulfhydryl-reactive diterpenes (like jatrophone). Glutathione may play a similar role in host and tumor cell responses to radiation, hyperthermia, and the reactive reduction products of oxygen secreted by inflammatory cells. Further, glutathione participates in the formation of toxic metabolites of such chemotherapeutics as azathioprine and bleomycin and may affect the cellular uptake of other agents, such as methotrexate. It seems likely that alterations in glutathione metabolism of tumor or host as a result of one therapeutic intervention may affect the outcome of concurrent treatments. Knowledge of these interactions may be useful in designing combination therapy for neoplastic disease.

m-AMSA and adenocarcinoma of the endometrium

Twenty-eight patients with advanced or recurrent adenocarcinoma of the endometrium were treated with m-AMSA. Twenty-four patients (86%) were treated at 30 mg/M2/d X 3d q 21 d and four patients were treated at 40 mg/M2/d X 3d q 21 d intravenously. Eighty-eight courses of m-AMSA were administered with a median of 2 courses per patient. One (5%) complete response occurred in 19 patients evaluable for response. Toxicity was well tolerated and generally mild. m-AMSA may be relatively inactive in the treatment of advanced adenocarcinoma of the endometrium; further studies, however, are required to determine its effectiveness in primary previously untreated disease.

Phase II study of PALA, amsacrine, teniposide, and zinostatin in small cell lung carcinoma (EST 2579)

Eighty-two patients with small cell lung carcinoma refractory to standard chemotherapy were entered in this phase II randomized study of PALA, amsacrine, teniposide, and zinostatin. Of the 66 evaluable patients, one partial response occurred among 17 patients treated with teniposide and no responses occurred with the other drugs. Two patients each treated with amsacrine and teniposide experienced life-threatening hematologic toxic effects and one patient treated with zinostatin died of thrombocytopenic pulmonary hemorrhage. The overall median patient survival was 9.6 weeks. Weight loss greater than or equal to 5% prior to therapy, extensive disease, and a nonambulatory status were associated with poor survival.

Acute electrocardiographic changes induced by amsacrine

The ECG effect of amsacrine (m-AMSA) was evaluated in 12 consecutive patients with leukemia. m-AMSA induced a significant prolongation of the Q-T interval (msecs, mean +/- SE) before (448 +/- 13) and 1 hour after (512 +/- 12) treatment (P . 0.0001, paired t test), without concomitant changes in the P-R interval, QRS duration, and heart rate. This selective cardiotoxic effect appeared to be transient and was noted towards the end of the iv drug administration, but was not present 24 hours later. No cardiac arrhythmias were noted during continuous monitoring. Nevertheless, it is assumed that the prolongation of the Q-T interval may represent a state of increased vulnerability to rhythm disturbances. Special care should be taken to avoid factors that may prolong the Q-T interval (hypokalemia, ischemia, or premedication with phenothiazine) during the administration of m-AMSA.

Effects of ruthenium red on accumulation and cytotoxicity of m-AMSA, vinblastine and daunorubicin in leukemia cells

Effects of ruthenium red on accumulation and cytotoxicity of m-AMSA, vinblastine and daunorubicin were examined in the P388 murine leukemia cell line and in an adriamycin-resistant subline, P388/ADR, which is cross-resistant to all three agents. Ruthenium red increased m-AMSA accumulation by both P388 and P388/ADR cells; the extent of this effect was a function of the concentration of both agents. Uptake enhancement occurred within 5 min of exposure of cells to ruthenium red and was readily reversed when cells were suspended in fresh medium. A 24-hr exposure to ruthenium red was needed to affect vinblastine or daunorubicin accumulation, and the effect was substantially less than that observed with m-AMSA. Ruthenium red protected P388 cells from m-AMSA toxicity. These data, together with reports indicating a protective effect of ruthenium red against vinblastine and anthracycline toxicity, suggest that the dye promotes tight binding of m-AMSA and other agents to cellular loci on which toxic effects are not exerted.

High-dose amsacrine (AMSA) therapy of relapsed and refractory adult acute nonlymphocytic leukemia A phase II study

Amsacrine (AMSA) has been shown to be an effective therapeutic agent in the treatment of adult acute nonlymphocytic leukemia (ANLL). The Eastern Cooperative Oncology Group studied the efficacy and toxicity of high-dose amsacrine (200 mg/m2/day for 5 days) in 38 adult patients with refractory and relapsed ANLL. The complete remission rate was low (8%). This dose level of amsacrine caused severe mucositis in 24% of patients and marked liver function abnormalities in 11%. Seizures did not occur, and two reversible cardiac events were not clearly attributable to amsacrine administration. Escalation of amsacrine beyond currently recommended total doses of 600-750 mg/m2 is unlikely to be of benefit.

[Combined therapy with AMSA and etoposide (VP 16-213) in refractory acute myeloid leukemia. A phase I study]

In a phase I study the combination of AMSA and etoposide was applied to 12 patients with intensively pretreated, refractory AML to evaluate the basis for a subsequent phase II study in terms of drug dosage and timing. Each treatment cycle consisted in a 5-day regimen of AMSA 210 mg/m2/d days 2, 3 and 4. Etoposide was administered on days 1 and 5 with a constant loading dose of 100 mg/m2 by an 1-h infusion followed by a 23-h infusion, the dose of which was escalated in 3 steps from 110 mg/m2 to 200 mg/m2 and 230 mg/m2. In 18 treatment cycles the recommended dosage for a subsequent phase II study was found to be 660 mg/m2 etoposide per cycle together with 630 mg/m2 AMSA per course. Main side effects were nausea and vomiting as well as mucositis; 1 patient developed a severe intrahepatic cholestasis. In 11 from 16 evaluable treatment cycles a significant reduction of bone marrow blasts was observed with a mean cytoreduction rate of 0,26 log10/d. 4 patients, 3 of whom were primarily resistent to 2 TAD induction courses, achieved a partial remission.

m-AMSA: phase II trial in advanced lymphoma and leukemia

m-AMSA, an acridine dye derivative, has been utilized in 36 patients with advanced hematologic malignancies. In 22 patients with lymphoma receiving 120 mg/m2 every 3 weeks, 10(45%) have achieved remissions. Eight of these remissions have been partial. The median duration of remission in patients with lymphoma was 3 months (range 1-12+ months). In 11 patients with acute leukemia receiving m-AMSA, 40 mg/m2 t.i.d. for 5 days, three (27%) have achieved remissions. Two of the three remissions have been complete. All three remissions in patients with leukemia were sustained for 1 month. Two patients with myeloma and one patient with chronic lymphocytic leukemia failed to respond. The major toxicity of m-AMSA has been myelosuppression. The dose-limiting toxic effect in patients with lymphoma was neutropenia. Nausea and vomiting, alopecia, phlebitis, and hepatic dysfunction have been noted in a minority of patients. Phlebitis appeared to be prevented with heparin administration after m-AMSA infusion. One fatal arrhythmia occurred, apparently related to therapy. m-AMSA appears active in advanced leukemia and lymphoma. Further studies are merited, particularly in combination with known effective agents, in order to improve upon remission duration.

Evaluation of AMSA in children with acute leukemia. A Pediatric Oncology Group study

One hundred four children with advanced leukemia in relapse (74 with acute lymphocytic leukemia [ALL] and 30 with acute nonlymphocytic leukemia [ANLL]) received AMSA (4'-(9-Acridinylamino) methanesulfon -m-anisidide) at a dose of 120 mg/m2/day for 5 days (Regimen I) or 60 mg/m2/day for 10 days (Regimen II). Children with ALL were randomized between Regimens I and II (31 and 36 evaluable patients, respectively). All 29 evaluable patients with ANLL were treated on Regimen I. Eighty-eight percent of evaluable patients experienced severe or life-threatening toxicity, with no statistical differences between Regimens I and II. Bacterial or fungal infections (considered life-threatening or fatal) occurred in 17 children with ALL and in 7 with ANLL. Fatal cardiac toxicity occurred in one patient. Complete or partial response occurred in 25.0% (SE = 8.8%), 28.1% (SE = 8.0%), and 25.9% (SE = 8.4%) of evaluable patients on ALL Regimen I, ALL Regimen II, and ANLL, respectively. However, responses were of short duration (16-91 days). There was no significant difference in the duration of survival from treatment start for the two ALL regimens (P = 0.46). The median duration of survival for ANLL patients was significantly longer (P = 0.004) than that of ALL patients treated on Regimens I and II combined. Eighty-two percent of the complete or partial responses (18 of 22) occurred after the first course of AMSA. At the dose schedules investigated, and in a heavily pretreated patient population, AMSA had activity in childhood leukemia. However, the high incidence of severe, life-threatening, or fatal infections meant that the quality and quantity of responses and survival was not commensurate with the toxicity, and that it would be difficult to incorporate this drug into combination chemotherapy with other myelosuppressive agents.

Formation and rejoining of deoxyribonucleic acid double-strand breaks induced in isolated cell nuclei by antineoplastic intercalating agents

The biochemical characteristics of the formation and disappearance of intercalator-induced DNA double-strand breaks (DSB) were studied in nuclei from mouse leukemia L1210 cells by using filter elution methodology [Bradley, M. O., & Kohn, K.W. (1979) Nucleic Acids Res. 7, 793-804]. The three intercalators used were 4'-(9-acridinylamino)-methanesulfon-m-anisidide (m-AMSA), 5-iminodaunorubicin (5-ID), and ellipticine. These compounds differ in that they produced predominantly DNA single-strand breaks (SSB) (m-AMSA) or predominantly DNA double-strand breaks (ellipticine) or a mixture of both SSB and DSB (5-ID) in whole cells. In isolated nuclei, each intercalator produced DSB at a frequency comparable to that which is produced in whole cells. Moreover, these DNA breaks reversed within 30 min after drug removal. It thus appeared that neither ATP nor other nucleotides were necessary for intercalator-dependent DNA nicking-closing reactions. The formation of the intercalator-induced DSB was reduced at ice temperature. Break formation was also reduced in the absence of magnesium, at a pH above 6.4 and at NaCl concentrations above 200 mM. In the presence of ATP and ATP analogues, the intercalator-induced cleavage was enhanced. These results suggest that the intercalator-induced DSB are enzymatically mediated and that the enzymes involved in these reactions can catalyze DNA double-strand cleavage and rejoining in the absence of ATP, although the occupancy of an ATP binding site might convert the enzyme to a form more reactive to intercalators. Three inhibitors of DNA topoisomerase II--novobiocin, nalidixic acid, and norfloxacin--reduced the formation of DNA strand breaks.(ABSTRACT TRUNCATED AT 250 WORDS)

Cytogenetic effects of amsacrine on human lymphocytes in vivo and in vitro

Amsacrine (m-AMSA) is presently being utilized in phase I-II studies at the Medicine Branch, National Cancer Institute, National Institutes of Health (Bethesda, MD), and is being administered as a continuous infusion to patients with progressive malignancy after conventional therapy. In the present study, we examined the effects of this drug, in vivo and in vitro, on chromosomal morphology and the frequency of sister chromatid exchange (SCE) induction in human peripheral blood lymphocytes. In the in vivo studies, eight patients receiving 30 mg/m2/day of m-AMSA by continuous infusion showed increased levels of chromosomal aberrations, up to a maximum of 14% (median; range, 10%-24%) at 96 hours compared to 1% (median; range, 0%-4%) in the control group; no increase was noted in SCE frequencies. In vitro studies of normal human lymphocytes with various concentrations of m-AMSA, including doses comparable to those used in vivo, showed both increased levels of chromosomal aberrations, ranging from 8% to 100%, and increased SCEs, ranging from 1.5 times the normal at the lowest concentration studied (0.005 microgram/ml) to 12 times the normal (0.25 microgram/ml). In correlating SCEs with breaks in the in vitro studies, it was found that two-thirds of the total breaks occurred at SCE points; this indicates a close relationship between the events leading to these two types of aberrations. In vitro isotope incorporation studies showed inhibition of both RNA and DNA syntheses but no significant inhibition of protein synthesis; at a dose of 5.0 micrograms/ml, RNA synthesis was 80% inhibited and DNA synthesis was 60% inhibited after 36 hours of incubation with m-AMSA. The difference in the results between in vitro and in vivo SCE studies may be due to possible DNA repair in the in vivo-treated lymphocytes in m-AMSA-free medium in vitro, a process not available to the in vitro-treated cells.