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Notes: Abstract Purpose:To determine the safety and activity of LY231514(ALIMTA™, MTA, pemetrexed disodium, Eli Lilly and Co.,Indianapolis, IN) in chemotherapy-naïve patients with advanced pancreaticcancer. Patients and methods:Patients with unresectable or metastaticpancreatic cancer received LY231514 600 mg/m2 as a 10–minuteinfusion every three weeks. Results:Forty-two patients were enrolled in this phase II trial.The median age was 60.3 (range 37–77) years; 79% had metastaticdisease. Neutropenia was common (40% of patients ≥ grade 3) butinfectious complications were rare. Significant anemia or thrombocytopeniaoccurred in 〈20% of patients. Non-hematologic toxicities includedgrade 2 or 3 skin reaction which was ameliorated by dexamethasone. Elevationsof bilirubin or transaminases were infrequent (〈25% of patients) anddid not require dose reductions or treatment delays. Thirty-five patientsreceived two cycles of therapy and were evaluable for response. One complete(duration 16.2 months) and one partial (duration 6.9 months) were observedresulting in an objective response rate of 5.7% for evaluable patients.In addition, 17 patients (40%) had stable disease that lasted ≥6months in 5 patients. The median survival was 6.5 months, with 28% ofpatients alive at one year. Conclusions:LY231514 is a well-tolerated agent with minimalobjective antitumor activity in pancreatic cancer. The median and one yearsurvival times, which may be important indicators in phase II trials of newagents, are of interest. Combination trials of LY231514 in pancreatic cancerare planned.

Notes: Abstract Purpose: The overall purpose of this study was to determine the potential efficacy of epoxide-containing piperazines as a new class of anti-cancer agents. Two representative compounds, specifically NCO-700, a 4-trimethoxyphenyl-substituted epoxide-piperazine, and TOP-008, a 4-phenylpropenyl-substituted epoxide-piperazine were tested in cytotoxic assays with human breast and prostate cancer cell lines. A second objective was to determine if these two compounds had anti-cancer activity in vivo when tested against xenograft tumors in nude mice or human tumors grown under the kidney capsule in mice. A final objective of this study was to establish if NCO-700 and TOP-008 achieved cancer cell killing through an apoptotic mechanism. Methods: The anti-proliferative activity of NCO-700 and TOP-008 were tested in a 7 day cell-survival assay utilizing a number of well characterized breast (HS-578T, T47D, MCF-7) and prostate (DU-145, PC-3, LNCaP) cancer cell lines. In vivo studies with the two compounds were performed, in nude mice bearing DU-145 xenograft tumors, and in normal mice in which DU-145 prostate cancer cells and HS-578T breast cancer cells were grown as solid tumors in the subrenal capsules of the animals. Apoptotic cell death of cancer cells was determined by a number of established techniques that detect apoptosis, including the confocal laser microscopy of treated cells and mitochondrial leakage assays utilizing the cationic dye, JC-1. Finally, the activation of the caspase cascade, enzymes that carry out apoptosis in mammalian cells, was examined in treated cells by immunoblot assays. Results: NCO-700 and TOP-008 displayed cytotoxicity to HS-578T human breast cancer cells, with ED50 values in the 3–6 μM range. Cytotoxicity to androgen receptor-negative human prostate cancer cells (PC-3 and DU-145 cells) occurred with ED50 values in the 5–20 μM range. Cytotoxicity to hormone receptor-positive breast and prostate cancer cell lines occurred at 10 to 20-fold higher concentrations of the two compounds. When human prostate (DU-145) or breast cancer (HS-578T) cells were grown as solid tumors in the subrenal capsules of mice, significant anti-tumor activity of NCO-700 was observed at 20 mg/kg and 50 mg/kg body weight respectively, for prostate and breast tumors. In nude mice bearing DU-145 prostate tumor xenografts, 50 mg/kg doses of the two compounds either stopped (TOP-008) tumor growth or slowed (NCO-700) growth. The mechanism of cytotoxicity was shown to be through apoptosis, (a) by confocal microscopy studies revealing nuclear fragmentation, (b) by mitochondrial studies revealing disruption of the mitochondrial membrane and release of the cationic dye, JC-1, into the cytoplasm and (c) by protein immunoblot assays indicating that over a 6 h period, TOP-008 induced a significant accumulation of the pro-apoptotic protein, bak, in the mitochondrial fraction of HS-578T human breast cancer cells, accompanied by activation, at 2.5 h, of caspase-3. Conclusions: These studies indicated that the epoxide-containing piperazines, as exemplified by NCO-700 and TOP-008, were effective anti-cancer agents when tested in vitro and in vivo against human breast and prostate tumors. Our studies also indicated that TOP-008 induced the initiation of the caspase cascade leading to apoptosis. Previous toxicology studies in rodents and dogs, as well as a Phase I study in humans, showed NCO-700 to be a well-tolerated, non-toxic compound. Taken together with our current findings, these results suggest that this class of compounds has the potential to be relatively safe, new chemotherapeutic agents for refractory breast and prostate cancers.

Notes: Abstract Introduction: CI-980 is a novel chemotherapeutic agent thatinhibits polymerization of tubulin. Preclinical studies haveindicated a high level activity of this agent against various tumorcell lines. Methods: 13 malignant melanoma patients who hadfailed prior chemotherapy and/or immunotherapy and 13 hormonerefractory prostate cancer patients, including 4 who had receivedprior chemotherapy, were treated in 2 separate NCI-supportedclinical trials. Subjects received a recommended phase II dose ofCI-980 of 4.5 mg/m2/day by continuous infusion for 72 hoursevery 3 weeks. Results: No activity was seen in either study.Toxicity was tolerable with neutropenia being the most common,significant toxicity. Among the melanoma patients, 15% and 31%developed grade 3 and grade 4 neutropenia, while 7% and 38% ofthe prostate patients developed grade 3 and grade 4 neutropenia,respectively. Conclusions: CI-980 at this dose and scheduleis ineffective against malignant melanoma and hormone refractoryprostate cancer.