zd-9331 and Colorectal-Neoplasms

Topics: Antineoplastic Agents; Clinical Trials as Topic; Colorectal Neoplasms; Enzyme Inhibitors; Folic Acid; Glutamates; Guanine; Humans; Pemetrexed; Quinazolines; Thiophenes; Thymidylate Synthase

Thymidylate synthase (TS) is a critical enzyme for DNA replication and cell growth because it is the only de novo source of thymine nucleotide precursors for DNA synthesis. TS is the primary target of 5-fluorouracil (5-FU), which has been used for cancer treatment for more than 40 years. However, dissatisfaction with the overall activity of 5-FU against the major cancers, and the recognition that TS still remains an attractive target for anticancer drugs because of its central position in the pathway of DNA synthesis, led to a search for new inhibitors of TS structurally analogous to 5,10-methylenetetrahydrofolate, the second substrate of TS. TS inhibitory antifolates developed to date that are in various stages of clinical evaluation are ZD 1694 and ZD9331 (Astra-Zeneca, London, UK), (Eli Lilly, Indianapolis, IN), LY231514 (BW1843U89 (Glaxo-Wellcome, Research Triangle Park, NC), and AG337 and AG331 (Agouron, La Jolla, CA). Although each of these compounds has TS as its major intracellular site of action, they differ in propensity for polyglutamylation and for transport by the reduced folate carrier. LY231514 also has secondary target enzymes. As a result, each compound is likely to have a different spectrum of antitumor activity and toxicity. This review will summarize the development and properties of this new class of TS inhibitors.

Topics: Animals; Antimetabolites, Antineoplastic; Colorectal Neoplasms; Enzyme Inhibitors; Folic Acid; Folic Acid Antagonists; Glutamates; Guanine; Humans; Indoles; Isoindoles; Pemetrexed; Quinazolines; Thiophenes; Thymidylate Synthase

This study investigated the efficacy and tolerability of ZD9331 as second- or third-line treatment for patients with advanced colorectal cancer (aCRC). One hundred patients were recruited to the study: 45 in group 1 (failed first-line 5-FU-based regimen) and 55 in group 2 (failed first-line 5-FU-based regimen and second-line irinotecan). Patients received ZD9331 as a 30-minute intravenous infusion on days 1 and 8 of a 3-week cycle, and treatment continued until disease progression (PD) or withdrawal. After a median of 4 cycles of treatment, there were no objective responses in group 1 (N = 37), 25 (67.6%) patients had a best overall response of stable disease (SD), and 12 (32.4%) had PD. After a median of 3 cycles of treatment, there were 2 (4.5%) partial responses in group 2 (N = 44), 21 (47.7%) patients had a best overall response of SD, 20 (45.4%) had PD, and 1 (2.3%) had clinical progression. At data cut-off, 59.5% and 77.3% of patients in groups 1 and 2, respectively, had PD. The main adverse events were neutropenia (69%), fatigue (53%), nausea (46%), and diarrhea (40%), and most (72.3%) were grade I/II. ZD9331 demonstrated minimal antitumor activity, and manageable toxicity, in the second- or third-line treatment of aCRC.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Colorectal Neoplasms; Drug Resistance, Neoplasm; Female; Humans; Male; Middle Aged; Quinazolines

ZD9331 is a novel thymidylate synthase inhibitor that, unlike some other antifolates, does not require polyglutamation for activity. This phase I dose-escalation trial investigated the tolerability, efficacy and pharmacokinetics of ZD9331 in Japanese patients with refractory, solid malignancies.. The mean age of patients was 57.6 years, and the most common primary tumours were gastric and colorectal cancer. Most patients had received prior chemotherapy and/or surgery. ZD9331 (69, 108 and 130 mg/m2/day) was administered as a 30-min i.v. infusion on days 1 and 8 of a 3-week cycle.. A total of 18 patients received ZD9331 treatment; six at each dose level. Patients received a median of 2 cycles of treatment ZD9331 demonstrated some antitumour activity, with one-third of patients showing no significant change in tumour size. ZD9331 was associated with non-dose-dependent myelosuppression, and dose-limiting toxicity was observed in one patient given 69 mg/m2/day and one patient given 130 mg/m2/day. The maximum plasma concentration and total area under the concentration-time curve increased with ZD9331 dose, whereas other pharmacokinetic parameters remained constant and independent of dose. Pharmacokinetic parameters were comparable following day 1 and 8 doses, with no accumulation of ZD9331 following the second dose.. ZD9331 has a manageable toxicity profile and shows some evidence of activity in Japanese patients with refractory, solid malignancies. The pharmacokinetic profile of ZD9331 in Japanese patients is similar to that observed in Western patients.

Topics: Adult; Colorectal Neoplasms; Drug Tolerance; Female; Humans; Japan; Male; Middle Aged; Neoplasms; Quinazolines; Stomach Neoplasms

5-Fluorouracil (5-FU) exerts cytotoxic effects through inhibition of thymidylate synthase (TS) and incorporation of metabolites into RNA. TS inhibition may be greater for infusional 5-FU, with bolus regimens more likely to cause RNA effects. Elevation of plasma 2'-deoxyuridine (dUrd) is a surrogate marker of TS inhibition. Nineteen patients were treated with continuous infusion (CI) 5-FU 300mg/m(2)/day or bolus 5-FU 425mg/m(2)/day plus leucovorin (LV) 20mg/m(2)/day days 1-5. Pretreatment (day 1) and day 2, 3, 4, 5, 8, 15, 22, and 29 plasma samples were assayed for dUrd by reverse-phase high-performance liquid chromatography. In patients treated with bolus 5-FU/LV, dUrd elevation at 24 and 48 h was 235 +/- 125 and 254 +/- 119%, respectively, falling to 138 +/- 58%, 156 +/- 89%, and 92 +/- 25% on days 8, 15, and 22, respectively. dUrd elevation with CI 5-FU was 229 +/- 86% at 24 h and 239 +/- 86, 240 +/- 98%, and 255 +/- 109% at days 15, 22, and 29, respectively. Duration of dUrd elevation was generally less than 8 days for bolus 5-FU/LV. A single dose of raltitrexed (3 mg/m(2)) gave a similar profile to this regimen. ZD9331 (130 mg/m(2), days 1 and 8) gave dUrd elevation for 14 of 21 days, with some recovery prior to day 8. Thus, both 5-FU regimens inhibit TS, and prolonged TS inhibition is achieved by CI 5-FU without significant toxicity. This suggests that the mechanism of antiproliferative toxicity from bolus 5-FU/LV is partly non-TS mediated. These results clarify underlying pharmacodynamic processes and could guide scheduling of 5-FU and TS inhibitors.

Topics: Antimetabolites, Antineoplastic; Biomarkers, Tumor; Colorectal Neoplasms; Deoxyuridine; Enzyme Inhibitors; Fluorouracil; Humans; Infusions, Intravenous; Quinazolines; Thiophenes; Thymidylate Synthase

The folate analogue BGC9331 is a new thymidylate synthase (TS) inhibitor showing a broad spectrum of cyto-toxic activity against several human solid tumors, including colorectal cancer. In this study, we investigated the anticancer activity of BGC9331 either alone or combined with 5-fluorouracil (5-FU), MTA (multi-target antifolate), oxali-platin and SN-38, the active metabolite of the topoisomerase I inhibitor CPT-11. The antiproliferative activity of each drug and BGC9331-based combinations was investigated in the HT-29 human colorectal cancer cell line and its HT-29/5-FU counterparts selected for resistance to 5-FU. BGC9331 combined with MTA or SN-38 induced synergistic responses in HT-29 cells. Treatment of HT-29 cells with either BGC9331 or SN-38 increased caspase-3 activity and the percentage of apoptotic cells from 3 to 13%. Both drugs also augmented the proteolytic cleavage of the Rho-kinase ROCK-1 that was attenuated by the caspase-3 pathway inhibitor z-DEVD-fmk. BGC9331 combined with SN-38 further increased the percentage of apoptotic cells to 25%, and inhibited cell cycle progression and cell proliferation by 65%. This was accompanied by proteolytic activation of ROCK-1, through both caspase-3-dependent and -independent mechanisms, as shown in caspase-3-deficient MCF-7 breast cancer cells. These encouraging results warrant further preclinical investigations and clinical trials on the use of BGC9331 combined with SN-38/CPT-11 in treatment of patients with advanced colorectal or gastric cancers.

Topics: Antineoplastic Agents; Apoptosis; Breast Neoplasms; Camptothecin; Caspase 3; Caspase Inhibitors; Caspases; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Cysteine Proteinase Inhibitors; DNA Topoisomerases, Type I; Dose-Response Relationship, Drug; Drug Synergism; Enzyme Inhibitors; Fluorouracil; Folic Acid Antagonists; Glutamates; Guanine; HT29 Cells; Humans; Intracellular Signaling Peptides and Proteins; Irinotecan; Oligopeptides; Organoplatinum Compounds; Oxaliplatin; Pemetrexed; Protein Serine-Threonine Kinases; Quinazolines; rho-Associated Kinases; Thymidylate Synthase; Time Factors; Topoisomerase I Inhibitors

We have demonstrated previously that interferon (IFN)-gamma sensitizes human colon carcinoma cell lines to the cytotoxic effects of 5-fluorouracil combined with leucovorin and to the thymidylate synthase inhibitor, ZD9331, dependent on thymineless stress-induced DNA damage, independent of p53. Here we demonstrate that the cyclin-dependent kinase (CDK) inhibitor p21(Cip1) regulates thymineless stress-induced cytotoxicity in these cells. HCT116 wild-type (wt) and p53-/- cells underwent apoptosis and loss in clonogenic survival when exposed to ZD9331, whereas p21Cip1-/- cells were resistant. In contrast, IFN-gamma induced marked cytotoxicity in p21Cip1-/- cells only. ZD9331 induced p21Cip1 up-regulation in all of the cell lines examined, as did thymidine deprivation in thymidylate synthase-deficient (thymidylate synthase-) cells. Furthermore, selective induction of p21Cip1 in RKO was sufficient to induce apoptosis. P21Cip1, cdk1, cdk2, and cyclin E mRNA expression increased coincident with S-phase accumulation in HT29 cells treated with ZD9331 or 5fluorouracil/leucovorin, as demonstrated by cDNA microarray analyses. Cell cycle analyses revealed that HCT116 wt and p21Cip1 -/- cells accumulated in S phase within 24 h of ZD9331 exposure; however, wt cells exited S-phase more rapidly, where apoptosis occurred before mitosis, either in late S or G2. Finally, the CDK inhibitor roscovitine potentiated the cytotoxic activity of ZD9331 in both wt and p21Cip1-/- cells, strongly suggesting a role for p21Cip1-dependent CDK inhibition in cytotoxicity induced by thymidylate synthase inhibition. In summary, p21Cip1 positively regulates the cytotoxic action of thymidylate synthase inhibitors, negatively regulates the cytotoxic action of IFN-gamma, and enhances S-phase exit after thymineless stress, possibly via interaction with CDK-cyclin complexes.

Topics: Apoptosis; Colorectal Neoplasms; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; Drug Synergism; Enzyme Inhibitors; fas Receptor; G1 Phase; HCT116 Cells; HT29 Cells; Humans; Interferon-gamma; Purines; Quinazolines; Roscovitine; S Phase; Thymidylate Synthase

Topics: Antibodies, Monoclonal; Antibodies, Monoclonal, Murine-Derived; Antineoplastic Combined Chemotherapy Protocols; Camptothecin; Capecitabine; Colorectal Neoplasms; Deoxycytidine; Fluorouracil; Humans; Irinotecan; Leucovorin; Organoplatinum Compounds; Oxaliplatin; Quinazolines