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Purpose: Angiosarcomas are rare, aggressive vascular tumours known to express vascular endothelial growth factor (VEGF), a key pro-angiogenic growth factor. The aim of this study was to determine the potential effects of vascular-targeted agents for the treatment of angiosarcoma, using two human cutaneous angiosarcoma cell lines (ASM and ISO-HAS), and human dermal microvascular endothelial cells (HuDMECs) for comparison., Methods: Protein arrays were used to assess the expression of angiogenesis-related proteins, and potential drug targets were assessed by ELISA and Western blotting. Response to vascular-targeted agents, including bevacizumab an anti-VEGF antibody, axitinib a VEGF-receptor tyrosine kinase inhibitor, everolimus an mTOR inhibitor, selumetinib a MEK inhibitor and vadimezan a vascular-disrupting agent were compared in functional in vitro cellular assays, including viability, differentiation and migration assays., Results: ASM and ISO-HAS cells expressed a broad range of pro-angiogenic growth factors. ASM and ISO-HAS VEGF expression was significantly increased (p = 0.029) compared with HuDMECs. Striking responses were seen to vadimezan with an IC50 of 90 and 150 μg/ml for ASM and ISO-HAS cells, respectively. Selumetinib inhibited ASM with an IC50 of 1,750 ng/ml, but was not effective in ISO-HAS. Everolimus reduced both ASM and ISO-HAS viable cell counts by 20 % (p < 0.001). Minimal responses were observed to bevacizumab and axitinib in assays with ASM and ISO-HAS cells., Conclusions: Further studies are warranted to investigate mTOR inhibitors, MEK inhibitors and vascular-disrupting agents for the treatment of angiosarcoma.

Purpose: Amsalog is a derivative of 9-aminoacridine. Phase I studies using intravenous (i.v.) amsalog have shown the dose-limiting toxicity (DLT) to be phlebitis and myelosuppression. Phase II studies using a variety of schedules have shown evidence of activity in patients with large-cell lung, breast, and head and neck cancers. Preclinical studies demonstrated that amsalog is active orally: a clinical study of the oral bioavailability of amsalog was therefore performed., Methods: A group of 20 patients with refractory malignancies were treated. There were two phases of the study: a pharmacokinetic comparison of i.v. against oral amsalog, followed by a pharmacokinetically guided oral dose escalation study. In the first phase of the study, 11 patients were treated. Amsalog 50 mg/m2 was administered i.v., and 50 mg/m2 and 200 mg/m2 orally. In the second phase of the study, 9 patients were treated in three cohorts of three. On day 1 of a 5-day schedule, amsalog was administered i.v. at the maximum tolerated dose (MTD) of 200 mg/m2. Subsequent doses were given orally, starting at a dose of 200 mg/m2 per day, with intrapatient dose escalation of up to 100% for the second cycle. Doses were escalated further in subsequent cohorts, based on oral bioavailability and toxicity., Results: Oral bioavailability of 50 mg/m2 amsalog was 34%. In the dose escalation phase, DLT was neutropenia; other toxicities included malaise and nausea. The MTD was 1600 mg/m2 per day for 5 days. The plasma AUC using 1600 mg/m2 by the oral route was higher than that achieved using 200 mg/m2 by the i.v. route., Conclusion: Amsalog can be tolerated orally on a 5-day schedule at doses up to 1600 mg/m2. The recommended dose for further evaluation is 800 mg/m2 daily for 5 days, repeated three weekly.

Purpose: Amsalog, a derivative of 9-aminoacridine, is an inhibitor of topoisomerase II. Early studies of intravenous amsalog administered either once weekly, or daily for 3 days repeated every 3 weeks, showed that myelosuppression is the dose-limiting toxicity (DLT). Phase II studies showed only limited activity in breast, head and neck, and non-small-cell lung cancer. The activity of other topoisomerase inhibitors is schedule-dependent. We therefore performed a phase I study to evaluate the use of amsalog on a more prolonged schedule., Methods: A group of 19 patients with refractory malignancies were treated in six cohorts using 2-h infusions of amsalog daily for 5 days, repeated every 3 weeks., Results: Myelosuppression was seen as DLT at 200 mg/m2 per day. Other toxicities included nausea and vomiting, fatigue, and, when administered via a peripheral venous line, severe phlebitis necessitating administration via an indwelling central venous catheter for doses greater than 100 mg/m2. Pharmacokinetic studies showed a linear relationship between Cmax and AUC, and dose. The terminal half-life was 2 h, consistent with previous studies., Conclusion: We conclude that amsalog can be safely given on a 5-day schedule every 3 weeks at doses up to 200 mg/m2. The dose recommended for further studies is 180 mg/m2 per day for 5 days repeated every 3 weeks. However, in view of the phlebitis, which necessitated the use of central venous catheters for administration, other routes of administration, for example oral formulations, should be explored.