aclarubicin and Carcinoma--Small-Cell

Topics: Aclarubicin; Adult; Aged; Carcinoma, Small Cell; Drug Administration Schedule; Drug Evaluation; Drug Resistance; Female; Humans; Lung Neoplasms; Male; Middle Aged; Recurrence

Topics: Aclarubicin; Adenocarcinoma; Adult; Aged; Antibiotics, Antineoplastic; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Clinical Trials as Topic; Drug Evaluation; Female; Humans; Lung Neoplasms; Male; Middle Aged; Naphthacenes

Aclacinomycin-A (ACLA-A), the new anthracycline antibiotic that produces substantially less cardiotoxicity relative to doxorubicin, was evaluated in a phase II trial for advanced large cell and adenocarcinoma of the lung patients. Twenty-three patients with measurable disease were entered into the trial and received ACLA-A in doses of a weekly infusion of 65 mg/m2 and 85 mg/m2. Eighteen patients were evaluable for response and toxicity. Two patients were evaluable for toxicity only, one died before completion of a full course of therapy, and two did not receive the drug. There were no complete or partial remissions in this study. Three patients had disease stabilization for a median of 10 weeks (range 6-17). Toxicity was mainly hematologic. Nausea and vomiting were moderate. ACLA-A, in the dose schedules used, appears to have no activity in large cell and adenocarcinoma of the lung.

Topics: Aclarubicin; Adenocarcinoma; Adult; Aged; Carcinoma, Small Cell; Clinical Trials as Topic; Drug Evaluation; Female; Humans; Infusions, Parenteral; Leukopenia; Lung Neoplasms; Male; Middle Aged; Naphthacenes; Nausea; Thrombocytopenia; Vomiting

In previous studies, we found that VP-16 (etoposide) induced cytotoxicity and protein-concealed strand break formation was prevented in a small cell lung cancer (SCLC) cell line, when the cells were incubated with aclarubicin prior to treatment with VP-16. In the present work, we studied the effect of adding aclarubicin to the cell suspension after VP-16. In a clonogenic assay, we found that the cytotoxicity induced by VP-16 in SCLC cells was inhibited when cells were postincubated with aclarubicin. The addition of aclarubicin at any time in relation to VP-16 was able to stop further cytotoxicity induced by the topoisomerase II (topo-II) targeting drug. Aclarubicin was also found to antagonize the cytotoxicity induced by VM-26 (teniposide), and m-AMSA. With the alkaline elution technique we found that postincubating the cells with aclarubicin inhibited VP-16-induced DNA strand break formation. In an in vitro system with purified topo-II and naked DNA we likewise found, that postincubation with aclarubicin prevented VP-16 induced cleavage. In the same in vitro system, also baseline cleavage induced by topo-II was inhibited when aclarubicin was present. Importantly, aclarubicin exerted the antagonism to topo-II targeting drugs both when administered prior to and after the topo-II targeting agents. Thus, our data suggest that sequential rather than simultaneous administration of aclarubicin and topo-II targeting agents may be superior with respect to net-cytotoxicity.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aclarubicin; Animals; Carcinoma, Small Cell; DNA Damage; DNA, Neoplasm; Etoposide; Humans; Lung Neoplasms; Mice; Time Factors; Topoisomerase II Inhibitors; Tumor Cells, Cultured; Tumor Stem Cell Assay

In contrast to the classic anthracyclines (doxorubicin and daunorubicin), aclarubicin (ACLA) does not stimulate topoisomerase II (topo II) mediated DNA-cleavage. This distinction may be important with respect to topo II-related drug resistance, and the aim of this study was to clarify drug-structures responsible for this difference. Various ACLA analogs were tested for: (a) interaction with purified topo II, (b) induction of DNA cleavage in cells, (c) cellular uptake and (d) cytotoxicity. A remarkable distinction was seen between analogs containing the chromophore aklavinone (AKV) (e.g. ACLA) which have a carboxymethyl group (COOCH3) at C-10 and drugs with a beta-rhodomycinone (RMN) chromophore with hydroxyl groups at C-10 and at C-11. Thus, RMN-containing analogs, including the aglycone RMN itself, effectively stimulated topo II-mediated DNA cleavage. In contrast, AKV-containing drugs inhibited DNA cleavage and antagonized cytotoxicity mediated by RMN-containing drugs. In OC-NYH/VM cells, exhibiting multidrug resistance due to an altered topo II phenotype (at-MDR), cross-resistance was only seen to the RMN-containing drugs whereas no cross-resistance was seen to the non-DNA cleaving AKV-containing compounds. Thus, our data show that one domain in the anthracycline is of particular importance for the interaction with topo II, namely the positions C-10 and C-11 in the chromophore, and further that at-MDR was circumvented by a COOCH3 substitution at position C-10. These findings may provide guidance for the synthesis and development of new analogs with activity in at-MDR cells.

Topics: Aclarubicin; Animals; Anthracyclines; Antibiotics, Antineoplastic; Carcinoma, Small Cell; DNA Damage; DNA Topoisomerases, Type II; DNA, Neoplasm; Drug Interactions; Drug Resistance; Drug Screening Assays, Antitumor; Humans; Leukemia L1210; Lung Neoplasms; Mice; Naphthacenes; Stimulation, Chemical; Structure-Activity Relationship; Topoisomerase II Inhibitors; Tumor Cells, Cultured

Anthracyclines possessing either a 9-alkyl modification in the A-ring of the tetracyclic aglycone and/or specific changes to the amino sugar moiety retain effective cytotoxic activity against multidrug resistant (MDR) cell lines. To obtain a better understanding of the structural features responsible for this potentially valuable behaviour, we used the MTT tetrazolium dye reduction assay to calculate resistance factors (RF = the ratio of ID50 for the drug-resistant line to that for the parental line) for the EMT6/P mouse mammary tumour and its MDR variant EMT6/AR1.0, and the H69/P human small cell lung cancer line and its MDR counterpart H69/LX4. Both MDR lines exhibit marked resistance to doxorubicin, MDR 1 gene amplification, hyperexpression of the membrane P-glycoprotein and reduced drug accumulation. RF values for doxorubicin were 34 and 131 in the EMT6 and H69 cell line pairs, respectively. The 9-alkyl-substituted anthracyclines were confirmed as having RF values 9- to 15-fold lower than those for doxorubicin. The 9-ethyl analogues Ro 31-1966 (RF for EMT6 2.2, RF for H69 4.7) and Ro 31-1749 (RF for EMT6 3.9, RF for H69 9.5) were superior to the previously studied 9-methyl analogue Ro 31-1215 (RF for EMT6 8.1 RF for H69 12.4). A clear trend for RF values to decrease with increasing 9-alkyl chain length was also noted in the structurally more complex aclacinomycin series. For example, 13-methyl-aclacinomycin (RF for EMT6 1.0, RF for H69 2.2) featuring a 9-isopropyl moiety was superior to the 9-alkyl-containing aclacinomycin A (RF for EMT6 4.7, RF for H69 5.8), and this was in turn more effective than the 9-methyl analogue sulfurmycin A (RF for EMT6 6.4, RF for H69 14.2). The trisaccharide moiety was not an essential feature for activity against MDR lines in the aclacinomycins, as shown by the low RF value with aklavine (RF for EMT6 2.1, RF for H69 2.5). However, a small change in one of the sugar moieties of aclacinomycin A, as in marcellomycin, resulted in a considerable increase in RF values (RF for EMT6 18.5, RF for H69 25.3). The complex anthracyclines AD 32 (RF for EMT6 6.5, RF for H69 11.7) and particularly tetrahydropyranyl-doxorubicin (RF for EMT6 1.4, RF for H69 3.2) were effective against MDR lines.(ABSTRACT TRUNCATED AT 400 WORDS)

Topics: Aclarubicin; Animals; Carcinoma, Small Cell; Doxorubicin; Drug Resistance; Drug Screening Assays, Antitumor; Humans; Lung Neoplasms; Mammary Neoplasms, Experimental; Mice; Structure-Activity Relationship; Tumor Cells, Cultured

The effect of combinations of the anthracyclines aclarubicin and daunorubicin was investigated in a clonogenic assay using the human small cell lung cancer cell line OC-NYH and a multidrug-resistant (MDR) murine subline of Ehrlich ascites tumor (EHR2/DNR+). It was found that the cytotoxicity of daunorubicin in OC-NYH cells was antagonized by simultaneous exposure to nontoxic concentrations of aclarubicin. Coordinately, aclarubicin inhibited the formation of daunorubicin-induced protein-concealed DNA single-strand breaks and DNA-protein cross-links in OC-NYH cells when assayed by the alkaline elution technique. Aclarubicin had no influence on the accumulation of daunorubicin in these cells. In contrast, the accumulation of daunorubicin in EHR2/DNR+ cells was enhanced by more than 300% when the cells were simultaneously incubated with the MDR modulator verapamil, aclarubicin, or the two agents combined. Yet the cytotoxicity of daunorubicin was potentiated significantly only by verapamil. The increased cytotoxicity of daunorubicin in the presence of verapamil was completely antagonized when aclarubicin was used together with the MDR modulator. Finally, the effect of daunorubicin on the DNA cleavage activity of purified topoisomerase II in the presence and absence of aclarubicin was examined. It was found that daunorubicin stimulated DNA cleavage by topoisomerase II at specific DNA sites. The addition of aclarubicin completely inhibited the daunorubicin-induced stimulation of DNA cleavage. Taken together, these data indicate that aclarubicin-mediated inhibition of daunorubicin-induced cytotoxicity is due mainly to a drug interaction with the nuclear enzyme topoisomerase II. This antagonism at the nuclear level explains why aclarubicin is a poor modulator of daunorubicin resistance even though aclarubicin is able to increase the intracellular accumulation of daunorubicin in a MDR cell line.

Topics: Aclarubicin; Animals; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Ehrlich Tumor; Carcinoma, Small Cell; Colony-Forming Units Assay; Daunorubicin; DNA; DNA Damage; DNA Replication; DNA Topoisomerases, Type II; Dose-Response Relationship, Drug; Drug Antagonism; Humans; In Vitro Techniques; Lung Neoplasms; Mice; Verapamil

The intramolecular combination of 9-alkyl substitution in the anthracycline A-ring plus incorporation of the amino group of the daunosamine sugar within a morpholinyl ring led to the retention of almost complete activity against P-glycoprotein positive, multidrug resistant variants of a mouse mammary tumour line and a human small cell lung cancer line. Resistance factors were close to unity. These structural elements may prevent efflux by the P-glycoprotein multidrug transporter. The use of 9-alkyl, morpholinyl anthracyclines with resistance circumvention properties may have clinical application.

Topics: Aclarubicin; Adjuvants, Immunologic; Animals; Antibiotics, Antineoplastic; ATP Binding Cassette Transporter, Subfamily B, Member 1; Carcinoma, Small Cell; Doxorubicin; Drug Resistance; Humans; Lung Neoplasms; Mammary Neoplasms, Experimental; Membrane Glycoproteins; Mice; Neoplasm Proteins; Tumor Cells, Cultured

The effect of combinations of the anthracycline aclarubicin and the topoisomerase II targeting drugs 4'-demethylepipodophyllotoxin-9-(4,6-O-ethylidene-beta-D-glucopyra noside) (VP-16) and 4'-(9-acridinylamino)methanesulfon-m-anisidide (m-AMSA) was investigated in a clonogenic assay. The cytotoxicity of VP-16 was almost completely antagonized by preincubating cells with nontoxic concentrations of aclarubicin. The inhibition of cytotoxicity was not seen when the cells were exposed to aclarubicin after exposure to VP-16. The inhibition was significant over a wide range of aclarubicin concentrations (3 nM to 0.4 microM), above which the toxicity of aclarubicin became apparent. A similar effect was seen on the toxicity of m-AMSA. In contrast to aclarubicin, preincubation with Adriamycin did not antagonize the effect of VP-16. With purified topoisomerase II and naked DNA, aclarubicin did not stimulate the formation of cleavable complexes between topoisomerase II and DNA. Aclarubicin concentrations above 1 microM inhibited the baseline formation of cleavable complexes elicited with the enzyme alone. Low (1 to 10 nM) aclarubicin concentrations increased the formation of cleavable complexes obtained with VP-16 and m-AMSA; however, at aclarubicin concentrations above 1 microM an antagonistic effect was obtained. In cells, the m-AMSA- and VP-16-induced, protein-concealed DNA strand breaks were completely inhibitable by aclarubicin preincubation with no synergic dose levels. Our results suggest that aclarubicin inhibits topoisomerase II-mediated DNA cleavage. This inhibition could represent the mechanism of action of the drug and explain the lack of cross-resistance to the classical anthracyclines. The observed antagonism could have consequences for scheduling of aclarubicin with topoisomerase II-active anticancer drugs.

Topics: Aclarubicin; Amsacrine; Carcinoma, Small Cell; Cell Survival; DNA Damage; DNA, Neoplasm; Doxorubicin; Etoposide; Humans; Lung Neoplasms; Topoisomerase II Inhibitors; Tumor Cells, Cultured

The cytotoxicity anti-tumour intercalating agents such as the anthraquinone mitoxantrone is thought to relate to DNA binding and the trapping of DNA topoisomerase II complexes on cellular DNA. We have studied the uptake, nuclear location, DNA binding mode and DNA damaging capacity of mitoxantrone in a small cell lung carcinoma cell line (NCI-H69) compared with an in vitro-derived variant subline (NCI-H69/LX4) that exhibits "classical" multi-drug resistance (MDR). Variant cells maintained under doxorubicin selection showed reduced RNA levels that returned to control values within 7 days of growth under non-selective conditions. Variant cells released from selection stress showed resistance to DNA cleavage by doxorubicin, mitoxantrone, 4'-epidoxorubicin, 4'-deoxy-doxorubicin but reduced resistance to aclacinomycin A and a 9-alkyl substituted anthracycline in broad agreement with the cross-resistance patterns for cytotoxicity. Mitoxantrone treated NCI-H69 cells were found to accumulate DNA-protein crosslinks during a 4 hr post-treatment incubation period whereas variant cells maintained depressed levels of crosslinking. There was no apparent abnormality in the availability or drug sensitivity of topoisomerase II assayed in crude nuclear extracts of NCI-H69/LX4 cells. Whole cell uptake of radiolabelled mitoxantrone was depressed (50%) in NCI-H69/LX4 compared with NCI-H69, whereas assessment of nuclear-bound drug in individual cells by a fluorescence quenching technique showed at least a 10-fold greater level of target protection. The quenching results provide evidence of a high affinity, saturable mode of drug binding, favoured at low drug concentrations, that correlated with DNA cleavage capacity. We propose that the cytotoxic action of mitoxantrone is dependent upon a restricted and persistent form of binding to DNA that favours the long-term or progressive trapping of topoisomerase II complexes.

Topics: Aclarubicin; Carcinoma, Small Cell; Cell Survival; DNA Damage; DNA Topoisomerases, Type II; DNA, Neoplasm; Doxorubicin; Drug Resistance; Enzyme Induction; Humans; Intercalating Agents; Lung Neoplasms; Mitoxantrone; Tumor Cells, Cultured

The sensitivity of eight cell lines established from treated and untreated patients with small cell carcinoma of the lung (SCCL) was tested in the clonogenic assay with 1 h and continuous exposure to aclarubicin (ACLA), adriamycin (ADR), daunorubicin (DAU) and mitoxantrone (MITO). The sensitivity to ADR, DAU and MITO covariated, and varied with a factor of five. The sensitivity to ACLA was independent of the sensitivity to ADR and varied only within a factor of two. Only ACLA showed pronounced increased potency with continuous incubation, and ACLA was the most potent drug in the three cell lines least sensitive to ADR. Two resistant cell lines were selected by treating NCI-H69 in vitro with DAU. One cell line (9-fold resistant to DAU) expressed large amounts of P-glycoprotein, the other cell line (4-fold resistant to DAU) had barely detectable glycoprotein. Both lines acquired resistance to ADR, ACLA and MITO. The cross-resistance to ACLA and MITO was only partial and ACLA was still the most potent drug on these lines. The sensitivity to ACLA of the cell lines least sensitive to ADR suggest that ACLA partially circumvents mechanisms of multidrug resistance. Together with the pronounced increase in potency with prolonged exposure, these results suggest that ACLA has a mechanism of action different from the 'classical' anthracyclines. In this context mitoxantrone is more similar to the classical anthracyclines although its structure is more dissimilar.

Topics: Aclarubicin; ATP Binding Cassette Transporter, Subfamily B, Member 1; Blood Proteins; Carcinoma, Small Cell; Daunorubicin; Doxorubicin; Drug Resistance; Drug Screening Assays, Antitumor; Humans; In Vitro Techniques; Lung Neoplasms; Membrane Glycoproteins; Mitoxantrone; Tumor Stem Cell Assay

Topics: Aclarubicin; Aged; Antineoplastic Combined Chemotherapy Protocols; Bleomycin; Bronchoalveolar Lavage Fluid; Bronchopneumonia; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Cisplatin; Cyclophosphamide; Doxorubicin; Humans; Lung; Lung Neoplasms; Male; Methotrexate; Middle Aged; Peplomycin; Vincristine

A series of experiments with ACM was performed to evaluate the effect for local treatment of malignant pleurisy from the view points of (1) clinical response, (2) pharmacokinetics following intrapleural administration, and (3) pleural reaction. The results were as follows: (1) In 6 patients with malignant pleural effusion, ACM was intrapleurally administered at a dose of 40 mg. In 4 out of the 5 evaluable cases, an extreme decrease in the pleural fluid volume and suppression of reswelling were observed, including 2 cases found to be negative for tumor cells upon cytodiagnosis. (2) In 5 patients, the pharmacokinetics was studied by using compartment model. The clearance curves of ACM in pleural fluid were described by a two-compartment model. The mean half lives of initial phase and terminal phase were 0.78 hr, and 15.28 hr, respectively. The time to reach the maximal whole blood level was 1 to 2 hrs after pleural administration, followed by a slow decline. (3) The pleural reaction to ACM was studied in rabbits by scanning and transmission electron microscope. At a dose of 4 mg per kg of body weight, the shortened microvilli, the degenerated mesothelial cells and the disappearance of basement membrane were observed. On the basis of these findings, we suggest that ACM might be an agent of choice in the treatment of malignant pleurisy.

Topics: Aclarubicin; Adenocarcinoma; Aged; Animals; Antibiotics, Antineoplastic; Breast Neoplasms; Carcinoma, Small Cell; Female; Humans; Lung Neoplasms; Male; Middle Aged; Naphthacenes; Pleural Effusion; Rabbits