A joined analysis of two European Organization for the Research and Treatment of Cancer (EORTC) studies to evaluate the role of pegylated liposomal doxorubicin (Caelyx) in the treatment of elderly patients with metastatic breast cancer.

We have performed a retrospective analysis to evaluate the impact of age, using a 70 year cutoff, on the safety and efficacy of pegylated liposomal doxorubicin (Caelyx) given at 60 mg/m(2) every 6 weeks (treatment A) or 50 mg/m(2) every 4 weeks (treatment B) to 136 metastatic breast cancer patients in two EORTC trials, of whom 65 were 70 years of age or older. No difference in terms of toxicity was observed between younger and older patients treated with the 4-week schedule, while a higher incidence of hematological toxicity, anorexia, asthenia, and stomatitis was observed in older patients when the 6-week schedule was used. Antitumor activity was not affected by age. In the older cohort of patients, no dependence was found between the incidence of grade 3-4 toxicity or antitumor activity and patients' baseline performance status, number and severity of comorbidities, or number of concomitant medications. The higher therapeutic index of Caelyx 50 mg/m(2) every 4 weeks makes it, of the two dose schedules investigated, the preferred regimen in the elderly.

Increasing doxorubicin activity against breast cancer cells using PPARγ-ligands and by exploiting circadian rhythms

Doxorubicin is effective against breast cancer, but its major side effect is cardiotoxicity. The aim of this study was to determine whether the efficacy of doxorubicin on cancer cells could be increased in combination with PPARγ agonists or chrono-optimization by exploiting the diurnal cycle. We determined cell toxicity using MCF-7 cancer cells, neonatal rat cardiac myocytes and fibroblasts in this study. Doxorubicin damages the contractile filaments of cardiac myocytes and affects cardiac fibroblasts by significantly inhibiting collagen production and proliferation at the level of the cell cycle. Cyclin D1 protein levels decreased significantly following doxorubicin treatment indicative of a G1 /S arrest. PPARγ agonists with doxorubicin increased the toxicity to MCF-7 cancer cells without affecting cardiac cells. Rosiglitazone and ciglitazone both enhanced anti-cancer activity when combined with doxorubicin (e.g. 50% cell death for doxorubicin at 0.1 μM compared to 80% cell death when combined with rosiglitazone). Thus, the therapeutic dose of doxorubicin could be reduced by 20-fold through combination with the PPARγ agonists, thereby reducing adverse effects on the heart. The presence of melatonin also significantly increased doxorubicin toxicity, in cardiac fibroblasts (1 μM melatonin) but not in MCF-7 cells. Our data show, for the first time, that circadian rhythms play an important role in doxorubicin toxicity in the myocardium; doxorubicin should be administered mid-morning, when circulating levels of melatonin are low, and in combination with rosiglitazone to increase therapeutic efficacy in cancer cells while reducing the toxic effects on the heart.

The mechanism of the pharmacological actions of dexrazoxane on different tissue types

Approximately 6,600 people die from acute myelogenous leukemia (AML) on an annual basis. During the past 10 to 15 years, there has been gradual overall improvements in the therapy of this disease, yet the majority of patients with AML succumb to this disease. In an attempt to improve current therapeutic strategies for AML, we became interested in a commercially available drug, dexrazoxane, which protects against anthracycline-induced cardiotoxicity. We have investigated dexrazoxane's (DEX) effects on different tissue types in an effort to determine its unique mechanism of action. Colony forming assays were used to evaluate stem-cell renewal of myeloid cells in vitro and median effect analysis was used to evaluate antagonism, synergism, or additivity. The anthracyclines, doxorubicin, daunorubicin, and idarubicin were individually combined with DEX in leukemic myeloid models to determine if the combination of the two drugs resulted in a synergistic, additive or antagonistic effect. Etoposide and cytosine arabinoside were also evaluated in combination with DEX using the same in vitro model and evaluated similarly. ^ Dexrazoxane in combination with any of the anthracyclines was schedule dependent. The combination of DEX and anthracycline resulted in a greater antitumor effect than anthracycline alone except for DEX administered 24 hours before doxorubicin or daunorubicin. These data were corroborated through median effect analysis. Etoposide in combination with dexrazoxane was synergistic for all combinations, and the combination of cytosine arabinoside and DEX was schedule dependent. In contrast, using an in vivo gastrointestinal model, DEX in combination with doxorubicin was antagonistic for almost all of the ratios used, except for the highest. A Withers' assay was used to evaluate toxicity on jejunal crypt cells. No effect was apparent for the combination of idarubicin and DEX, however, as seen with RZ, DEX in addition to radiation greatly potentiated the cytotoxic effects of radiation on crypts. These paradoxical effects of dexrazoxane were initially enigmatic, but after additional investigation, we propose a model that explains our findings. We conclude that DEX in combination with anthracyclines produces an additive to synergistic antileukemic response and may have therapeutic potential clinically. Additionally, DEX protects the gastrointestinal tract from doxorubicin toxicity, which could have clinical implications for the administration of greater doses of doxorubicin. ^

Doxorubicin-paclitaxel: a safe regimen in terms of cardiac toxicity in metastatic breast carcinoma patients. Results from a European Organization for Research and Treatment of Cancer multicenter trial.

BACKGROUND: The potential cardiotoxicity of the doxorubicin-paclitaxel regimen, when paclitaxel is given shortly after the end of the anthracycline infusion, is an issue of concern, as suggested by small single institution Phase II studies. METHODS: In a large multicenter Phase III trial, 275 anthracycline naive metastatic breast carcinoma patients were randomized to receive either doxorubicin (60 mg/m(2)) followed 30 minutes later by paclitaxel (175 mg/m(2) 3-hour infusion; AT) or a standard doxorubicin-cyclophosphamide regimen (AC; 60/600 mg/m(2)). Both treatments were given once every 3 weeks for a maximum of six cycles. Close cardiac monitoring was implemented in the study design. RESULTS: Congestive heart failure (CHF) occurred in three patients in the AT arm and in one patient in the AC arm (P = 0.62). Decreases in left ventricular ejection fraction to below the limit of normal were documented in 33% AT and 19% AC patients and were not predictive of CHF development. CONCLUSIONS: AT is devoid of excessive cardiac risk among metastatic breast carcinoma patients, when the maximum planned cumulative dose of doxorubicin does not exceed 360 mg/m(2).

Improved efficacy and reduced toxicity of doxorubicin encapsulated in sulfatide-containing nanoliposome in a glioma model

As a glycosphingolipid that can bind to several extracellular matrix proteins, sulfatide has the potential to become an effective targeting agent for tumors overexpressing tenasin-C in their microenvironment. To overcome the dose-limiting toxicity of doxorubicin (DOX), a sulfatide-containing nanoliposome (SCN) encapsulation approach was employed to improve treatment efficacy and reduce side effects of free DOX. This study analysed in vitro characteristics of sulfatidecontaining nanoliposomal DOX (SCN-DOX) and assessed its cytotoxicity in vitro, as well as biodistribution, therapeutic efficacy, and systemic toxicity in a human glioblastoma U-118MG xenograft model. SCN-DOX was shown to achieve highest drug to lipid ratio (0.5:1) and a remarkable in vitro stability. Moreover, DOX encapsulated in SCN was shown to be delivered into the nuclei and displayed prolonged retention over free DOX in U-118MG cells. This simple two-lipid SCN- DOX nanodrug has favourable pharmacokinetic attributes in terms of prolonged circulation time, reduced volume of distribution and enhanced bioavailability in healthy rats. As a result of the improved biodistribution, an enhanced treatment efficacy of SCNDOX was found in glioma-bearing mice compared to the free drug. Finally, a reduction in the accumulation of DOX in the drug’s principal toxicity organs achieved by SCN-DOX led to the diminished systemic toxicity as evident from the plasma biochemical analyses. Thus, SCN has the potential to be an effective and safer nano-carrier for targeted delivery of therapeutic agents to tumors with elevated expression of tenascin-C in their microenvironment.

In vivo evaluation of the genetic toxicity of Rubus niveus Thunb. (Rosaceae) extract and initial screening of its potential chemoprevention against doxorubicin-induced DNA damage

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A phase II study of Caelyx, liposomal doxorubicin : lack of activity in patients with advanced gastric cancer

Purpose A phase II study was designed to assess the efficacy and safety of Caelyx (liposomal doxorubicin) in patients with advanced or metastatic gastric cancer. Methods A total of 25 patients with gastric adenocarcinoma were treated with Caelyx 45 mg/m2 every 28 days as first-line therapy for advanced disease. Patients were treated until tumour progression or unacceptable toxicity. Results One patient was withdrawn from the study after experiencing a severe infusion reaction. Of the 24 evaluable patients, 1 had a partial response, 7 had stable disease and the others progressed. Side effects, in particular palmar-plantar erythrodysaesthesia and haematological toxicity, were minor. Conclusions We conclude that while this dose and schedule of Caelyx in this patient group is acceptable, further studies with this regimen cannot be recommended due to the lack of antitumour activity seen.

Paclitaxel versus doxorubicin as first-line single-agent chemotherapy for metastatic breast cancer: a European Organization for Research and Treatment of Cancer Randomized Study with cross-over.

PURPOSE: To compare the efficacy of paclitaxel versus doxorubicin given as single agents in first-line therapy of advanced breast cancer (primary end point, progression-free survival ¿PFS) and to explore the degree of cross-resistance between the two agents. PATIENTS AND METHODS: Three hundred thirty-one patients were randomized to receive either paclitaxel 200 mg/m(2), 3-hour infusion every 3 weeks, or doxorubicin 75 mg/m(2), intravenous bolus every 3 weeks. Seven courses were planned unless progression or unacceptable toxicity occurred before the seven courses were finished. Patients who progressed within the seven courses underwent early cross-over to the alternative drug, while a delayed cross-over was optional for the remainder of patients at the time of disease progression. RESULTS: Objective response in first-line therapy was significantly better (P =.003) for doxorubicin (response rate ¿RR, 41%) than for paclitaxel (RR, 25%), with doxorubicin achieving a longer median PFS (7.5 months for doxorubicin v 3.9 months for paclitaxel, P <.001). In second-line therapy, cross-over to doxorubicin (91 patients) and to paclitaxel (77 patients) gave response rates of 30% and 16%, respectively. The median survival durations of 18.3 months for doxorubicin and 15.6 months for paclitaxel were not significantly different (P =.38). The doxorubicin arm had greater toxicity, but this was counterbalanced by better symptom control. CONCLUSION: At the dosages and schedules used in the present study, doxorubicin achieves better disease and symptom control than paclitaxel in first-line treatment. Doxorubicin and paclitaxel are not totally cross-resistant, which supports further investigation of these drugs in combination or in sequence, both in advanced disease and in the adjuvant setting.

A randomised phase II study of two different schedules of pegylated liposomal doxorubicin in metastatic breast cancer (EORTC-10993).

One hundred and sixteen women with measurable metastatic breast cancer participated in a randomised phase II study of single agent liposomal pegylated doxorubicin (Caelyx) given either as a 60 mg/m2 every 6 weeks (ARM A) or 50 mg/m2 every 4 weeks (ARM B) schedule. Patients were over 65 years of age or, if younger, had refused or been unsuitable for standard anthracyclines. The aims of the study were to evaluate toxicity and dose delivery with the two schedules and obtain further information on the response rate of liposomal pegylated doxorubicin as a single agent in anthracycline nai ve advanced breast cancer. Twenty-six patients had received prior adjuvant chemotherapy (including an anthracycline in 10). Sixteen had received non-anthracycline-based first-line chemotherapy for advanced disease. One hundred and eleven patients were evaluable for toxicity and 106 for response. The delivered dose intensity (DI) was 9.8 mg/m2 (95% CI, 7.2-10.4) with 37 (69%) achieving a DI of >90% on ARM A and 11.9 mg/m2 (95% CI, 7.5-12.8) with 37 (65%) achieving a DI of >90% on ARM B. The adverse event profiles of the two schedules were distinctly different. Mucositis was more common with the every 6 weeks regimen (35% CTC grade 3/4 in ARM A, 14% in ARM B) but palmar plantar erythrodysesthesia (PPE) was more frequent with the every 4 weeks regimen (2% CTC grade 3/4 in ARM A, 16% in ARM B). Confirmed objective partial responses by RECIST criteria were seen with both schedules; 15/51 (29%) on ARM A and 17/56 (31%) on ARM B. Liposomal pegylated doxorubicin showed significant activity in advanced breast cancer with a generally favourable side-effect profile. The high frequency of stomatitis seen with 6 weekly treatment makes this the less preferred of the two schedules tested.

Doxorubicin and paclitaxel versus doxorubicin and cyclophosphamide as first-line chemotherapy in metastatic breast cancer: The European Organization for Research and Treatment of Cancer 10961 Multicenter Phase III Trial.

PURPOSE: To compare the efficacy and tolerability of the combination of doxorubicin and paclitaxel (AT) with a standard doxorubicin and cyclophosphamide (AC) regimen as first-line chemotherapy for metastatic breast cancer. PATIENTS AND METHODS: Eligible patients were anthracycline-naive and had bidimensionally measurable metastatic breast cancer. Two hundred seventy-five patients were randomly assigned to be treated with AT (doxorubicin 60 mg/m(2) as an intravenous bolus plus paclitaxel 175 mg/m(2) as a 3-hour infusion) or AC (doxorubicin 60 mg/m(2) plus cyclophosphamide 600 mg/m(2)) every 3 weeks for a maximum of six cycles. A paclitaxel (200 mg/m(2)) and cyclophosphamide (750 mg/m(2)) dose escalation was planned at cycle 2 if no grade >or= 3 neutropenia occurred in cycle 1. The primary efficacy end point was progression-free survival (PFS). Secondary end points were response rate (RR), safety, overall survival (OS), and quality of life. RESULTS: A median number of six cycles were delivered in the two treatment arms. The relative dose-intensity and delivered cumulative dose of doxorubicin were lower in the AT arm. Dose escalation was only possible in 17% and 20% of the AT and AC patients, respectively. Median PFS was 6 months in the two treatments arms. RR was 58% versus 54%, and median OS was 20.6 versus 20.5 months in the AT and AC arms, respectively. The AT regimen was characterized by a higher incidence of febrile neutropenia, 32% versus 9% in the AC arm. CONCLUSION: No differences in the efficacy study end points were observed between the two treatment arms. Treatment-related toxicity compromised doxorubicin-delivered dose-intensity in the paclitaxel-based regimen

Increased anti-tumour efficacy of doxorubicin when combined with sulindac in a xenograft model of an MRP-1-positive human lung cancer

Background: A number of cellular proteins, including P-glycoprotein (P-gp) and Multiple drug Resistance Protein (MRP-1), act as drug efflux pumps and are important in the resistance of many cancers to chemotherapy. We previously reported that a small number of NSAIDs could inhibit the activity of MRP-1. Materials and Methods: We chose sulindac as a candidate agent for further investigation as it has the most favourable efficacy and toxicity profile of the agents available for a potential specific MRP-1 inhibitor. NCI H460 cells expressed MRP-1 protein (by Western blot) and also the toxicity, of doxorubicin (a substrate of MRP-1) could be potentiated in this line using non-toxic concentrations of the MRP-1 substrate/inhibitor sulindac. These cells were implanted in nude mice and the animals divided into various groups which were administered doxorubicin and/or sulindac. Results: Sulindac was shown to significantly potentiate the tumour growth inhibitor activity of doxorubicin in this MRP-1-overexpressing human tumour xenograft model. Conclusion: Sulindac may be clinically useful as an inhibitor of the MRP-1 cancer resistance mechanism.

Doxorubicin In Vivo Rapidly Alters Expression and Translation of Myocardial Electron Transport Chain Genes, Leads to ATP Loss and Caspase 3 Activation

Background: Doxorubicin is one of the most effective anti-cancer drugs but its use is limited by cumulative cardiotoxicity that restricts lifetime dose. Redox damage is one of the most accepted mechanisms of toxicity, but not fully substantiated. Moreover doxorubicin is not an efficient redox cycling compound due to its low redox potential. Here we used genomic and chemical systems approaches in vivo to investigate the mechanisms of doxorubicin cardiotoxicity, and specifically test the hypothesis of redox cycling mediated cardiotoxicity.

Acute Eosinophilic and Neutrophilic Pneumonia following Transarterial Chemoembolization with Drug-Eluting Beads Loaded with Doxorubicin for Hepatocellular Carcinoma: A Case Report.

At an intermediate or advanced stage, i.e. stage B or C, based on the Barcelona Clinic Liver Cancer classification of hepatocellular carcinoma (HCC), transarterial chemoembolization (TACE) may be offered as a treatment of palliative intent. We report the case of a patient suffering from acute respiratory distress syndrome after TACE with drug-eluting beads loaded with doxorubicin for HCC. To our knowledge, this is the first case described where a bronchoalveolar lavage was performed, and where significant levels of alveolar eosinophilia and neutrophilia were evident, attributed to a pulmonary toxicity of doxorubicin following liver chemoembolization. © 2014 S. Karger AG, Basel.