amrubicinol and amrubicin

To evaluate the pharmacokinetics and cardiac repolarization effect (measured by QT/QTc interval) of amrubicin and its active metabolite amrubicinol in non-Japanese patients with advanced solid tumors.. Patients received amrubicin 40 mg/m(2)/day as a 5-min infusion on days 1-3 of a 21-day cycle. During cycle 1, serial blood and plasma samples were collected on days 1-9 and time-matched triplicate electrocardiograms on the "off-drug" visit (1-5 days prior to start of treatment) and days 1-9.. Twenty-four patients were treated. Amrubicinol reached peak concentration 2-4 h after amrubicin administration and had a terminal half-life of 53 h. Distribution of amrubicinol into erythrocytes was fivefold greater than into plasma. The molar ratio of amrubicinol to amrubicin in blood was 0.67 on day 3. The presence of an NQO1 polymorphism did not alter drug exposure. The upper bound of the one-sided 95 % confidence interval for the time-matched, baseline-adjusted change from the off-drug day in QTcI (individual correction) was <10 ms at all times and was only >10 ms (10.20 ms) at a single time point for QTcF (Fridericia correction). No relationship was observed between blood amrubicin or amrubicinol concentrations and QTcF changes. All QTcF measurements were <480 ms, and none increased by >60 ms from baseline.. Data suggest that amrubicinol is an important active metabolite in humans and that both compounds were not associated with clinically relevant QTc interval prolongation at the dose regimen studied.

Topics: Adult; Aged; Anthracyclines; Antineoplastic Agents; Electrocardiography; Female; Heart; Heart Rate; Humans; Male; Middle Aged; NAD(P)H Dehydrogenase (Quinone); Neoplasms

Amrubicinol (AMR-OH) is an active metabolite of amrubicin (AMR), a novel synthetic 9-aminoanthracycline derivative. The time-concentration profile of AMR-OH exhibits a continuous long plateau slope in the terminal phase. To determine the relationships between the steady-state plasma concentration of AMR-OH and treatment effects and toxicities associated with AMR therapy, we carried out a pharmacokinetic/pharmacodynamic study in patients treated with AMR alone or the combination of AMR+cisplatin (CDDP). AMR was given at a dose of 30 or 40 mg/m(2) on days 1-3. Plasma samples were collected 24 h after the third injection (day 4). Plasma concentrations of AMR-OH or total CDDP were determined by a high-performance liquid chromatography or an atomic absorption spectrometry. Percent change in neutrophil count (dANC) and the plasma concentration of AMR-OH were evaluated using a sigmoid E(max) model. A total of 35 patients were enrolled. Significant relationships were observed between AMR-OH on day 4 and the toxicity grades of leukopenia, neutropenia, and anemia (P=0.018, P=0.012, and P=0.025, respectively). Thrombocytopenia grade exhibited a tendency toward relationship with AMR-OH on day 4 (P=0.081). The plasma concentration of AMR-OH on day 4 was positively correlated with dANC in the group of all patients, as well as in patients treated with AMR alone and in patients coadministered with CDDP. In conclusion, the plasma concentration of AMR-OH on day 4 was correlated with hematological toxicities in patients treated with AMR. The assessment of plasma concentration of AMR-OH at one timepoint might enable the prediction of hematological toxicities.

Topics: Adult; Aged; Anthracyclines; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Drug Administration Schedule; Female; Hematologic Diseases; Humans; Leukopenia; Lung Neoplasms; Male; Middle Aged; Neutropenia; Treatment Outcome

Amrubicin is a novel synthetic 9-aminoanthracycline derivative and is converted enzymatically to its C-13 hydroxy metabolite, amrubicinol, whose cytotoxic activity is 10-100 times that of amrubicin. We aimed to determine the maximum tolerated dose (MTD) of amrubicin and to characterize the pharmacokinetics of amrubicin and amrubicinol in previously treated patients with refractory or relapsed lung cancer. The 15 patients were treated with amrubicin intravenously at doses of 30, 35, or 40 mg/m(2) on three consecutive days every 3 weeks for a total of 43 courses. Neutropenia was the major toxicity (grade 4, 67%). The MTD was 40 mg/m(2), with the specific dose-limiting toxicities being grade 4 neutropenia persisting for >4 days, febrile neutropenia, or grade 3 arrhythmia in the three patients treated at this dose. A patient with non-small-cell lung cancer showed a partial response, and ten individuals experienced a stable disease. The area under the plasma concentration versus time curve (AUC) for amrubicin and that for amrubicinol increased with amrubicin dose. The amrubicin AUC was significantly correlated with the amrubicinol AUC. The recommended phase II dose of amrubicin for patients with lung cancer refractory to standard chemotherapy is thus 35 mg/m(2) once a day for three consecutive days every 3 weeks.

Topics: Aged; Anthracyclines; Antineoplastic Agents; Area Under Curve; Atrial Fibrillation; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Chromatography, High Pressure Liquid; Disopyramide; Dose-Response Relationship, Drug; Drug Administration Schedule; Dyspnea; Female; Half-Life; Humans; Hypoxia; Infusions, Intravenous; Leukopenia; Male; Middle Aged; Neoplasm Recurrence, Local; Neutropenia; Platelet Transfusion; Pneumonia; Steroids; Thrombocytopenia

Amrubicin, a synthetic 9-aminoanthracycline agent, was recently approved in Japan for treatment of small-cell lung cancer and non-small-cell lung cancer. Amrubicin is converted enzymatically to the C-13 hydroxy metabolite amrubicinol, which is active and possesses a cytotoxicity 10 to 100 times that of the parent drug. The purpose of this study was to characterize the pharmacokinetics of amrubicin and its active metabolite amrubicinol. Amrubicin was administered on days 1-3 in 16 patients with advanced lung cancer. The pharmacokinetics analysis of amrubicin and amrubicinol was performed by high-performance liquid chromatography. When 45 mg/m amrubicin was administered in a bolus injection once every 24 hours for 3 consecutive days, the areas under the curves (0 to 72 hours) for amrubicin and amrubicinol were 13,490 and 2585 ng . h/mL, respectively. The apparent total clearance (CLapp) of amrubicin was 15.4 L/h. The area-under-the-curve ratio of amrubicinol to amrubicin was 15.1 +/- 4.6% (mean +/- SD) at doses ranging from 30 to 45 mg/m. Interindividual variability in the enzymatic conversion of amrubicin to amrubicinol was small. In contrast, a large interindividual variability in the CLapp of amrubicin was observed (CV = 49.8%). The areas under the curves of amrubicin and amrubicinol seemed to be associated with the severity of hematologic toxicities. There is a possibility that monitoring of the plasma concentrations of amrubicin and amrubicinol may provide an efficient tool for establishing the optimal dosage of amrubicin in each patient.

Topics: Aged; Anthracyclines; Area Under Curve; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Chromatography, High Pressure Liquid; Female; Humans; Leukopenia; Lung Neoplasms; Male; Middle Aged; Thrombocytopenia

Amrubicin (AMR) has shown promising activity for lung cancer. However, little is known about the mechanism underlying resistance to this agent. The aim of this study was to elucidate the mechanism underlying resistance to AMR.. We first developed amrubicinol (AMR-OH)-resistant cell lines (H520/R and DMS53/R) by exposing lung cancer cell lines (H520 and DMS53) to increasing concentrations of AMR-OH and performed functional analysis by using these cell lines.. Transcriptome analyses showed that amphiregulin (AREG) was the most highly up-regulated gene in both AMR-OH-resistant cell lines compared to parent cells. Conditioned medium from DMS53/R cells reduced the sensitivity to AMR-OH in DMS53 cells. In contrast, DMS53/R cells transfected with siRNA directed against AREG recovered their sensitivity to AMR-OH. An additional administration of cetuximab with amrubicinol also restored the sensitivity to AMR-OH.. Amphiregulin plays an important role in resistance to AMR-OH.

Topics: Amphiregulin; Animals; Anthracyclines; Antineoplastic Agents; Cell Line, Tumor; Drug Resistance, Neoplasm; Female; Humans; Lung Neoplasms; Mice, Inbred BALB C; Mice, Nude; RNA, Small Interfering; Tumor Burden

Limited sampling points for both amrubicin (AMR) and its active metabolite amrubicinol (AMR-OH) were simultaneously optimized using Akaike's information criterion (AIC) calculated by pharmacokinetic modeling.. In this pharmacokinetic study, 40 mg/m(2) of AMR was administered as a 5-min infusion on three consecutive days to 21 Japanese lung cancer patients. Blood samples were taken at 0, 0.08, 0.25, 0.5, 1, 2, 4, 8 and 24 h after drug infusion, and AMR and AMR-OH concentrations in plasma were quantitated using a high-performance liquid chromatography. The pharmacokinetic profile of AMR was characterized using a three-compartment model and that of AMR-OH using a one-compartment model following a first-order absorption process. These pharmacokinetic profiles were then integrated into one pharmacokinetic model for simultaneous fitting of AMR and AMR-OH. After fitting to the pharmacokinetic model, 65 combinations of four sampling points from the concentration profiles were evaluated for their AICs. Stepwise regression analysis was applied to select the sampling points for AMR and AMR-OH to predict the area under the concentration-time curves (AUCs) at best.. Of the three combinations that yielded favorable AIC values, 0.25, 2, 4 and 8 h yielded the best AUC prediction for both AMR (R(2) = 0.977) and AMR-OH (R(2) = 0.886). The prediction error for AUC was less than 15%.. The optimal limited sampling points of AMR and AMR-OH after AMR infusion were found to be 0.25, 2, 4 and 8 h, enabling less frequent blood sampling in further expanded pharmacokinetic studies for both AMR and AMR-OH.

Topics: Aged; Anthracyclines; Antineoplastic Agents; Area Under Curve; Female; Humans; Lung Neoplasms; Male; Middle Aged

The pharmacokinetic (PK)-pharmacodynamic (PD) relationship of amrubicin and its active metabolite, amrubicinol, has only been evaluated using trough levels of these agents since the full PK profiles not yet been clarified so far. This study was performed to analyze the full PK profiles of amrubicin and amrubicinol and to evaluate their toxicity-PK relationships in Japanese patients.. Amrubicin (35-40 mg/m(2)) was administered to 21 lung cancer patients on days 1-3 every 3-4 weeks. Fourteen blood samples were obtained per patient over the course of 3 administration days. The plasma concentrations of amrubicin and amrubicinol were quantitated by HPLC, and the relationships between PK parameters of these compounds and hematological toxicities were evaluated.. The overall PK profiles of amrubicin and amrubicinol were well characterized using a 3-compartment model and a 1-compartment model with a first-order metabolic process, respectively. The major toxicities were hematological. The clearance of amrubicinol was significantly correlated with grade 4 neutropenia (P = 0.01). The percentage decreases in the neutrophil count, hemoglobin level and platelet count were well correlated with the amrubicinol AUC.. The pharmacokinetic profiles of amrubicin and amrubicinol were clarified, and the subsequent PK-PD analyses indicate that the clearance of amrubicinol is the major determinant of neutropenia.

Topics: Adult; Aged; Aged, 80 and over; Anthracyclines; Carcinoma, Non-Small-Cell Lung; Female; Humans; Japan; Lung Neoplasms; Male; Middle Aged; Small Cell Lung Carcinoma

Anthracycline-related cardiotoxicity correlates with cardiac anthracycline accumulation and bioactivation to secondary alcohol metabolites or reactive oxygen species (ROS), such as superoxide anion (O₂·⁻) and hydrogen peroxide H₂O₂). We reported that in an ex vivo human myocardial strip model, 3 or 10 μM amrubicin [(7S,9S)-9-acetyl-9-amino-7-[(2-deoxy-β-D-erythro-pentopyranosyl)oxy]-7,8,9,10-tetrahydro-6,11-dihydroxy-5,12-napthacenedione hydrochloride] accumulated to a lower level compared with equimolar doxorubicin or epirubicin (J Pharmacol Exp Ther 341:464-473, 2012). We have characterized how amrubicin converted to ROS or secondary alcohol metabolite in comparison with doxorubicin (that formed both toxic species) or epirubicin (that lacked ROS formation and showed an impaired conversion to alcohol metabolite). Amrubicin and doxorubicin partitioned to mitochondria and caused similar elevations of H₂O₂, but the mechanisms of H₂O₂ formation were different. Amrubicin produced H₂O₂ by enzymatic reduction-oxidation of its quinone moiety, whereas doxorubicin acted by inducing mitochondrial uncoupling. Moreover, mitochondrial aconitase assays showed that 3 μM amrubicin caused an O₂·⁻-dependent reversible inactivation, whereas doxorubicin always caused an irreversible inactivation. Low concentrations of amrubicin therefore proved similar to epirubicin in sparing mitochondrial aconitase from irreversible inactivation. The soluble fraction of human myocardial strips converted doxorubicin and epirubicin to secondary alcohol metabolites that irreversibly inactivated cytoplasmic aconitase; in contrast, strips exposed to amrubicin failed to generate its secondary alcohol metabolite, amrubicinol, and only occasionally exhibited an irreversible inactivation of cytoplasmic aconitase. This was caused by competing pathways that favored formation and complete or near-to-complete elimination of 9-deaminoamrubicinol. These results characterize amrubicin metabolic advantages over doxorubicin and epirubicin, which may correlate with amrubicin cardiac safety in preclinical or clinical settings.

Topics: Aconitate Hydratase; Alcohols; Anthracyclines; Antineoplastic Agents; Cytoplasm; Doxorubicin; Epirubicin; Humans; Hydrogen Peroxide; Mitochondria; Myocardium; Oxidation-Reduction; Reactive Oxygen Species; Troponin I

Amrubicin, a totally synthetic 9-aminoanthracycline anticancer drug, has shown promising activity for lung cancer, but little is known about the mechanism of resistance for this agent. This study was aimed to clarify the role of P-glycoprotein (P-gp) in amrubicinol, an active metabolite of amrubicin, resistance in lung cancer cells.. Amrubicinol-resistant cell line PC-6/AMR-OH was developed by continuously exposing the small-cell lung cancer cell line PC-6 to amrubicinol. Gene expression level of MDR1, which encodes P-gp, and intracellular accumulation of amrubicinol were evaluated by PC-6 and PC-6/AMR-OH cells. The involvement of MDR1 in amrubicinol resistance was evaluated by treatment with P-gp inhibitor verapamil and small interfering RNA (siRNA) against MDR1. Also, expression levels and single-nucleotide polymorphisms (SNPs) of MDR1 in 22 lung cancer cell lines were examined, and the relationships between these factors and sensitivity to amrubicinol were evaluated.. The MDR1 gene was increased approximately 4,500-fold in PC-6/AMR-OH cells compared with PC-6 cells, and intracellular accumulation of amrubicinol in PC-6/AMR-OH cells was decreased to about 15 percent of that in PC-6 cells. Treatment with verapamil and siRNA against MDR1 significantly increased the sensitivity to amrubicinol in PC-6/AMR-OH cells with increased cellular accumulation of amrubicinol. Meanwhile, neither MDR1 gene expression levels nor SNPs of the gene were associated with amrubicinol sensitivity.. Results of this study indicate that increased MDR1 expression and P-gp activity confer acquired resistance to amrubicinol. In contrast, neither expression level nor SNPs of MDR1 are likely to be predictive markers for amrubicin activity.

Topics: Animals; Anthracyclines; ATP Binding Cassette Transporter, Subfamily B, Member 1; Calcium Channel Blockers; Drug Resistance, Neoplasm; LLC-PK1 Cells; Lung Neoplasms; Polymorphism, Single Nucleotide; Reverse Transcriptase Polymerase Chain Reaction; RNA Interference; RNA, Neoplasm; RNA, Small Interfering; Swine; Verapamil

A simple and sensitive high-performance liquid chromatographic (HPLC) method was developed for determination of amrubicin and its metabolite amrubicinol in human plasma. After protein precipitation with methanol without evaporation procedure, large volume samples were injected and separated by two monolithic columns with a guard column. The mobile phase consisted of tetrahydrofuran-dioxane-water (containing 2.3 mM acetic acid and 4 mM sodium 1-octanesulfonate; 2:6:15, v/v/v). Wavelengths of fluorescence detection were set at 480 nm for excitation and 550 nm for detection. Under these conditions, linearity was confirmed in the 2.5-5000 ng/mL concentration range of both compounds. The intra- and inter-day precision and intra- and inter-day accuracy for both compounds were less than 10%. The method was successfully applied to a clinical pharmacokinetic study of amrubicin and amrubicinol in cancer patients.

Topics: Anthracyclines; Antineoplastic Agents; Chromatography, High Pressure Liquid; Humans; Lung Neoplasms; Prospective Studies; Sensitivity and Specificity

This study examined the pharmacokinetics of irinotecan (CPT-11), active metabolite 7-ethyl-10-hydroxycamptothecin (SN-38), SN-38 glucuronide (SN-38G) amrubicin (AMR), and active metabolite amrubicinol (AMR-OH) after intravenous administration of this combination therapy in rats.. Male Sprague-Dawley rats were treated with 10 mg/kg CPT-11 with 10 mg/kg AMR. AMR, AMR-OH, CPT-11, SN-38 and SN-38G were measured in plasma, bile, and tissues using high-performance liquid chromatography.. Co-administration of CPT-11 resulted in a significant decrease in plasma concentrations and area under the curves (AUC) of AMR-OH compared with treatment with AMR alone. On the other hand, co-administration of AMR resulted in a slight increase in the initial plasma concentration of SN-38; however, there were no differences in AUC values in CPT-11 and SN-38. The cumulative biliary excretion curves of AMR, CPT-11, and their active metabolites were not changed. CPT-11 inhibited the conversion of AMR to AMR-OH in rat cytosolic fractions.. CPT-11 did not affect the pharmacokinetic of AMR but decreased the plasma concentration of AMR-OH and might affect the formation of AMR-OH from AMR in hepatocytes.

Topics: Animals; Anthracyclines; Antineoplastic Combined Chemotherapy Protocols; Camptothecin; Drug Interactions; Glucuronides; Irinotecan; Liver; Male; Rats; Rats, Sprague-Dawley; Tissue Distribution

Amrubicin is a new anticancer drug that has been shown to exert efficacy against small cell lung cancer. The pharmacokinetic parameters of amrubicin have not yet been investigated in hemodialysis patients, although it had been expected that amrubicin might not be cleared by hemodialysis because of its high lipid solubility, high protein binding rate and low urinary excretion rate. We encountered a case of small cell lung cancer on hemodialysis who was treated with amrubicin. We assayed the plasma concentrations of amrubicin and amrubicinol (its active metabolite) and analyzed the pharmacokinetic parameters of the drug in this hemodialysis patient. The results revealed that the pharmacokinetic parameters of the drug in this patient undergoing hemodialysis were similar to those in patients not on hemodialysis. Our results suggest that amrubicin and amrubicinol are cleared by hemodialysis, and that dose adjustment of amrubicin might not be required in hemodialysis patients.

Topics: Anthracyclines; Antineoplastic Agents; Humans; Lung Neoplasms; Male; Middle Aged; Renal Dialysis; Small Cell Lung Carcinoma

Amrubicin is a completely synthetic 9-aminoanthracycline agent for the treatment of lung cancer in Japan. The cytotoxicity of C-13 hydroxy metabolite, amrubicinol, is 10 to 100 times greater than that of amrubicin. The transporters responsible for the intracellular pharmacokinetics of amrubicin and amrubicinol remains unclear. This study was aimed to determine whether P-glycoprotein (P-gp) plays functional and preventive role in cellular accumulation and cytotoxicity of amrubicin and its active metabolite amrubicinol by in vitro transport and toxicity experiments. Cytotoxicity and intracellular accumulation of amrubicin and amrubicinol were evaluated by LLC-PK1 cells, MDR1 gene-transfected LLC-PK1 (L-MDR1) cells overexpressing P-gp, and human A549 lung adenocarcinoma cells. L-MDR1 cells showed 6- and 12-fold greater resistance to amrubicin and amrubicinol, respectively, than the parental LLC-PK1 cells. The intracellular accumulation of both drugs in L-MDR1 cells was significantly reduced compared to the LLC-PK1 cells. The basal-to-apical transepithelial transport of both drugs markedly exceeded, whereas the apical-to-basal transport of both drugs was significantly lower in L-MDR1 cells than LLC-PK1 cells. Cyclosporin A (CyA) restored the sensitivity, intracellular accumulation and transport activity for both drugs in L-MDR1 cells. In A549 cells, CyA significantly increased the intracellular accumulation and cytotoxicity of both drugs. These findings indicated that P-gp is responsible for cellular accumulation and cytotoxicity of both amrubicin and amrubicinol, therefore suggesting that the antitumor effect of amrubicin could be affected by the expression level of P-gp in lung cancer cells in chemotherapeutic treatments.

Topics: Adenocarcinoma; Animals; Anthracyclines; Antineoplastic Agents; ATP Binding Cassette Transporter, Subfamily B, Member 1; Biological Transport; Cell Line, Tumor; Cell Survival; Drug Resistance, Neoplasm; Humans; LLC-PK1 Cells; Lung Neoplasms; Molecular Structure; Swine; Transfection

Amrubicin, a completely synthetic 9-aminoanthracycline derivative, is an active agent in the treatment of untreated extensive disease-small-cell lung cancer and advanced non-small-cell lung cancer. Amrubicin administered intravenously at 25 mg/kg substantially prevented the growth of five of six human lung cancer xenografts established in athymic nude mice, confirming that amrubicin as a single agent was active in human lung tumors. To survey which antitumor agent available for clinical use produces a synergistic interaction with amrubicin, we examined the effects in combinations with amrubicinol, an active metabolite of amrubicin, of several chemotherapeutic agents in vitro using five human cancer cell lines using the combination index (CI) method of Chou and Talalay. Synergistic effects were obtained on the simultaneous use of amrubicinol with cisplatin, irinotecan, gefitinib and trastuzumab, with CI values after 3 days of exposure being <1. Additive effect was observed with the combination containing vinorelbine with CI values indistinguishable from 1, while the combination of amrubicinol with gemcitabine was antagonistic. All combinations tested in vivo were well tolerated. The combinations of cisplatin, irinotecan, vinorelbine, trastuzumab, tegafur/uracil, and to a lesser extent, gemcitabine with amrubicin caused significant growth inhibition of human tumor xenografts without pronouncedly enhancing body weight loss, compared with treatment using amrubicin alone at the maximum tolerated dose. Growth inhibition of tumors by gefitinib was not antagonized by amrubicin. These results suggest that amrubicin appears to be a possible candidate for combined use with cisplatin, irinotecan, vinorelbine, gemcitabine, tegafur/uracil or trastuzumab.

Topics: Animals; Anthracyclines; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antimetabolites, Antineoplastic; Antineoplastic Agents; Antineoplastic Agents, Phytogenic; Camptothecin; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Cell Line, Tumor; Cisplatin; Deoxycytidine; Drug Synergism; Female; Gefitinib; Gemcitabine; Humans; In Vitro Techniques; Irinotecan; Lung Neoplasms; Mice; Mice, Nude; Quinazolines; Random Allocation; Stomach Neoplasms; Tegafur; Trastuzumab; Uracil; Vinblastine; Vinorelbine; Xenograft Model Antitumor Assays

We previously demonstrated the doxorubicin-induced expression of urokinase-type plasminogen activator (uPA), interleukin-8 (IL-8), monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-alpha in human RC-K8 lymphoma cells and NCI-H69 small cell lung carcinoma cells in which reactive oxygen species might be involved. Amurubicin hydrochloride (AMR), a novel derivative drug of doxorubicin, was recently introduced to clinical practice for treatment of lung cancer in Japan. Therefore, we investigated the effects of AMR on the expression of uPA and chemokines in NCI-H69 cells. AMR and its active form, amurubicinol hydrochloride (AMROH), both induced the expression of uPA, IL-8 and MCP-1 in H69 cells in a dose-dependent manner. When the cultured supernatant obtained from AMR-treated H69 cells was subcutaneously injected into rabbits, migration of a significant number of eosinophils was observed around the injected site. Antigen levels of eotaxin-3, a major migration-factor of eosinophils, were increased in AMROH-treated cells in parallel with the mRNA levels. The induction was observed below the clinically achievable concentration of AMR or AMROH. Thus, the simultaneous induction of uPA, IL-8, MCP-1 and eotaxin-3 may play a role in the pharmacological action of AMR through induction of the interaction between proinflammatory cells and lung carcinoma cells.

Topics: Animals; Anthracyclines; Blotting, Northern; Carcinoma, Small Cell; Cell Line, Tumor; Cell Movement; Chemokine CCL2; Chemokine CCL26; Chemokines, CC; Culture Media, Conditioned; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Eosinophils; Gene Expression Regulation, Neoplastic; Humans; Injections, Subcutaneous; Interleukin-8; Lung Neoplasms; Rabbits; RNA, Messenger; Urokinase-Type Plasminogen Activator

Amrubicin, a completely synthetic 9-aminoanthracycline derivative, inhibits cell growth by stabilizing a topoisomerase II-DNA complex. This study was designed to examine the apoptosis induced in human leukemia U937 cells by amrubicin and its active metabolite amrubicinol. Amrubicin, amrubicinol and other antitumor agents, such as daunorubicin and etoposide, induced typical apoptosis with characteristic nuclear morphological change and DNA fragmentation. Measuring the population of sub-G(1) phase cells, it was found that under conditions where cell growth was inhibited by either amrubicin or amrubicinol, U937 cells underwent apoptotic cell death in a dose-dependent manner accompanied by an arrest of the cell cycle at G(2)/M. Furthermore, amrubicin- and amrubicinol-induced apoptosis was mediated by the activation of caspase-3/7, but not caspase-1, preceding a loss of mitochondrial membrane potential. These results indicate that both a reduction in mitochondrial membrane potential and the activation of caspase-3/7 are key events in the apoptosis induced by amrubicin and amrubicinol as well as the other antitumor agents. In addition, studies with oligomycin suggested that the apoptosis induced by amrubicin and amrubicinol involved substantially different pathways from that triggered by daunorubicin and etoposide. Oligomycin blocked the etoposide-induced increase in the number of sub-G(1) phase cells without preventing the activation of caspase-3/7, and had no inhibitory effect on the expansion of the sub-G(1) population in daunorubicin-treated cells, whereas apoptosis-related changes caused by amrubicin and amrubicinol were suppressed in the presence of oligomycin.

Topics: Anthracyclines; Antibiotics, Antineoplastic; Antineoplastic Agents; Antineoplastic Agents, Phytogenic; Apoptosis; Caspase 3; Caspase 7; Cell Division; Daunorubicin; Drug Therapy, Combination; Enzyme Activation; Etoposide; G2 Phase; Humans; Membrane Potentials; Mitochondria; Tumor Cells, Cultured; U937 Cells

The effects of amrubicin (AMR) and its active metabolite, amrubicinol (AMROH), on the sensitivity of human lung adenocarcinoma A549 cells to ionizing radiation were investigated in vitro. Further, the kinetics of apoptosis and necrosis induction were also analyzed. The cytocidal effects of X-ray irradiation on A549 cells resulted in a low level of radiosensitivity with a D0 value of 12 Gy. The slopes of the survival curves in the exponential phase were plotted on semilogarithmic paper for radiation combined with AMR (2.5 microg/ml) and AMROH (0.02 microg/ml) treatment, and were shown to be approximately parallel to treatment with irradiation alone. The initial shoulder-shape portion of the survival curve for radiation alone, indicating the repair of sublethal damage, was reduced as compared to that for sequential combined treatment with AMR or AMROH. Sequential treatments with AMR or AMROH prior to ionizing radiation resulted in an additive radio-enhancement effect that reduced not only survival, but also the shoulder width. Fractionated irradiation with 2 Gy per fraction of A549 cells was carried out in vitro similar to that commonly performed in clinical radiotherapy and the radio-resistance of the cells was shown to be inhibited by AMR and AMROH. Similar to AMR and AMROH, adriamycin and etoposide (VP-16) are DNA topoisomerase II inhibitors. The effects of these 4 agents on cells that received X-ray irradiation were compared and all of the agents exhibited comparable radio-enhancement effects. The induction of apoptosis was investigated at 48 and 72 h after administration of AMROH, radiation or combined treatment, and apoptosis was not significantly induced after any of the treatments. We also examined the induction of necrosis, and found that the incidence of necrosis following combined treatment was approximately 2 times higher than that with either of the single treatments.

Topics: Adenocarcinoma; Anthracyclines; Apoptosis; Cell Line, Tumor; Humans; Kinetics; Lung Neoplasms; Necrosis; Radiation Tolerance; Radiation-Sensitizing Agents; Topoisomerase II Inhibitors; X-Rays

The effects of amrubicin (AMR) and its active metabolite, amrubicinol (AMROH), on the sensitivity of human lung adenocarcinoma A549 cell line to hyperthermia at 44 degrees C were investigated. The cell phase response as well as the kinetics of apoptosis and necrosis induction were also analyzed. The cytocidal effects of 44 degrees C hyperthermia on A549 cells exhibited low thermosensitivity with a T(0) value of 12 min. The slope of the survival curve in the exponential phase, described semilogarithmically, in 44 degrees C hyperthermia combined treatment with AMROH (0.02 microg/ml) was approximately parallel to 44 degrees C hyperthermia alone. The initial shoulder shape portion of the survival curve from 44 degrees C hyperthermia alone, indicating the repair of sublethal thermal damage (SLTDR), was reduced with the sequential combined treatment of AMR or AMROH. Sequential treatments with AMR or AMROH prior to 44 degrees C hyperthermia resulted in additive thermo-enhancement effect by reducing not only survival but was shoulder wide. Furthermore, like AMR and AMROH, adriamycin (ADM) and etoposide (VP-16) are DNA topoisomerase II inhibitors, and the effects of these 4 agents on 44 degrees C hyperthermia were compared. All 4 agents exhibited comparable thermo-enhancement effects. Using synchronized A549 cells, AMR or AMROH did not elicit cell phase responses, irrespective of the concentration. The induction of apoptosis was investigated at 48 and 72 h after AMROH treatment, 44 degrees C hyperthermia or the combined treatment, in which apoptosis was not significantly induced after any treatment. Furthermore, the incidence of necrosis was examined as well as apoptosis. The incidence of necrosis at 48 and 72 h after AMROH was 2.4 and 4.3%, respectively; after 44 degrees C hyperthermia was 3.3 and 4.0%, respectively; and after the combined treatment it was 10.7 and 8.7%, respectively. The necrosis induced after the combined treatment was circa 3 times higher than that in either of the single treatments.

Topics: Adenocarcinoma; Anthracyclines; Apoptosis; Cell Line, Tumor; Cell Survival; Doxorubicin; Drug Synergism; Etoposide; Hot Temperature; Humans; Lung Neoplasms; Necrosis; Time Factors

The in vitro metabolism of amrubicin by rat and human liver microsomes and cytosol was examined. The main metabolic routes in both species were reductive deglycosylation and carbonyl group reduction in the side-chain. In vitro metabolism of amrubicinol by rat and human liver microsomes and cytosol was also examined and the main metabolic route of this active metabolite was reductive deglycosylation. Metabolism of amrubicin in human liver microsomes was inhibited by TlCl(3) and that in human liver cytosol was inhibited by dicumarol and quercetin. Generation of amrubicinol was inhibited only by quercetin. The results indicate that metabolism of amrubicin is mediated by NADPH-cytochrome P450 reductase, NADPH:quinone oxidoreductase and carbonyl reductase. In addition, generation of amrubicinol is mediated by carbonyl reductase. Metabolism of amrubicinol in human liver microsomes was inhibited by TlCl(3) and that in human liver cytosol was inhibited by dicumarol. The results indicate that metabolism of amrubicinol is mediated by NADPH-cytochrome P450 reductase and NADPH:quinone oxidoreductase. To investigate the influence of cisplatin on the metabolism of amrubicin and amrubicinol, human liver microsomes and cytosol were pre-incubated with cisplatin. This did not change the rates of amrubicin and amrubicinol metabolism in either human liver microsomes or cytosol.

Topics: Adult; Aged; Animals; Anthracyclines; Cisplatin; Cytosol; Enzyme Inhibitors; Female; Humans; In Vitro Techniques; Male; Microsomes, Liver; Middle Aged; Models, Biological; Rats; Time Factors

Amrubicin, a 9-aminoanthracycline anti-cancer drug, and its C-13 hydroxyl metabolite amrubicinol, were examined for growth-inhibitory activity as well as cellular uptake and distribution in P388 murine leukemia cells and doxorubicin-resistant P388 cells. Also discussed are the differences in the mechanisms of action among amrubicin, amrubicinol and doxorubicin in terms of their cellular pharmacokinetic character. In P388 cells, amrubicinol was about 80 times as potent as amrubicin, and about 2 times more potent than doxorubicin in a 1-h drug exposure growth-inhibition test. A clear cross-resistance was observed to both amrubicin and amrubicinol in doxorubicin-resistant P388 cells, though the resistance index was lower for amrubicin. The intracellular concentration of amrubicinol was about 6 times and 2 times higher than those of amrubicin and doxorubicin, respectively. Compared to doxorubicin, amrubicin and amrubicinol were released rapidly after removal of the drugs from the medium. A clear correlation was found between the growth-inhibiting activity and the cellular level of amrubicin and amrubicinol in P388 cells. About 10 to 20% of amrubicin or amrubicinol taken up by the cells was detected in the cell nuclear fraction, whereas 70 to 80% of doxorubicin was localized in this fraction. These results suggest that amrubicin and amrubicinol exert cytotoxic activity via a different mechanism from that of doxorubicin.

Topics: Animals; Anthracyclines; Antibiotics, Antineoplastic; Cell Division; Drug Resistance, Neoplasm; Leukemia P388; Mice; Tumor Cells, Cultured

It has been reported that the 9-aminoanthracycline amrubicin shows good efficacy in human tumor xenograft models. We studied the disposition and metabolism of amrubicin in mice, in comparison with those of doxorubicin. Amrubicinol, a 13-hydroxy metabolite of amrubicin, which is 10 to 100 times more cytotoxic than amrubicin, was detected as a major metabolite in blood and tissues, and aglycones of amrubicin were also detected. A pharmacokinetic study revealed that amrubicin had a smaller distribution volume and a shorter half-life than doxorubicin. In several normal tissues, the levels of amrubicin and amrubicinol were lower than those of doxorubicin. In contrast, the tumor levels of amrubicinol in the mice treated with amrubicin were higher than those of doxorubicin in the mice treated with that drug, in tumors that are sensitive to amrubicin. These results suggest that the potent therapeutic activity of amrubicin is caused by the selective distribution of its highly active metabolite, amrubicinol, in tumors.

Topics: Animals; Anthracyclines; Antibiotics, Antineoplastic; Doxorubicin; Female; Half-Life; Humans; Male; Metabolic Clearance Rate; Mice; Mice, Inbred BALB C; Mice, Nude; Models, Biological; Stomach Neoplasms; Tissue Distribution; Transplantation, Heterologous

Amrubicin, a completely synthetic 9-aminoanthracycline derivative, was previously shown to have potent antitumor activities against various human tumor xenografts. In this study, the in vitro activities of amrubicin and its major metabolite, amrubicinol, were examined using 17 human tumor cell lines. Amrubicinol was 5 to 54 times more potent than amrubicin, and as potent as doxorubicin, in inhibiting the growth of the cells following 3-day continuous drug exposure. Amrubicinol closely resembled doxorubicin in its profile of activities on the 17 human tumor cell lines. Cells were incubated with the drugs for 1 h, and the intracellular drug concentration and cell growth inhibition after 3 days were determined. Amrubicinol attained similar intracellular concentrations at lower medium concentrations compared to amrubicin, and the intracellular concentration of amrubicinol necessary to produce 50% cell growth inhibition was 3 to 8 times lower than that of amrubicin in 4 cell lines tested. Amrubicinol has a higher activity level inside the cells than does amrubicin. When cells were incubated with amrubicin for 5 h, a substantial amount of amrubicinol, more than 9% of that of amrubicin, was found in cells in 4 of the 8 cell lines tested. Amrubicinol may contribute to the in vitro growth-inhibitory effect of amrubicin on these cells. The results suggest that amrubicinol plays an important role in the in vivo antitumor effect of amrubicin as an active metabolite.

Topics: Anthracyclines; Antibiotics, Antineoplastic; Biotransformation; Cell Division; Cell Survival; Colonic Neoplasms; Hematologic Neoplasms; Humans; Kidney Neoplasms; Lung Neoplasms; Osteosarcoma; Tumor Cells, Cultured; U937 Cells; Urinary Bladder Neoplasms

Amrubicin is a novel, completely synthetic 9-aminoanthracycline derivative. Amrubicin and its C-13 alcohol metabolite, amrubicinol, inhibited purified human DNA topoisomerase II (topo II). Compared with doxorubicin (DXR), amrubicin and amrubicinol induced extensive DNA-protein complex formation and double-strand DNA breaks in CCRF-CEM cells and KU-2 cells. In this study, we found that ICRF-193, a topo II catalytic inhibitor, antagonized both DNA-protein complex formation and double-strand DNA breaks induced by amrubicin and amrubicinol. Coordinately, cell growth inhibition induced by amrubicin and amrubicinol, but not that induced by DXR, was antagonized by ICRF-193. Taken together, these findings indicate that the cell growth-inhibitory effects of amrubicin and amrubicinol are due to DNA-protein complex formation followed by double-strand DNA breaks, which are mediated by topo II.

Topics: Anthracyclines; Antibiotics, Antineoplastic; Catalysis; Cell Division; DNA Damage; DNA Topoisomerases, Type II; DNA, Neoplasm; Doxorubicin; Drug Screening Assays, Antitumor; Enzyme Stability; Humans; Intercalating Agents; Topoisomerase II Inhibitors; Tumor Cells, Cultured