The aim of the study was to determine whether modulation of 5-fluorouracil (FU) by methotrexate (MTX) improves survival compared to FU+6-s-leucovorin (LV) following potentially curative resection of stage II and III colon cancer. Within 8 weeks from surgery, 1945 patients with stage III (44%) or high-risk stage II (55%) colon cancer were randomly assigned to receive either 6 monthly cycles of FU 370 mg m(-2) i.v. bolus preceded by LV 100 mg m(-2) i.v. bolus on days 1-5, or 6 monthly cycles of sequential MTX 200 mg m(-2) i.v. days 1 and 15 and FU 600 mg m(-2) i.v. on days 2 and 16 followed by LV rescue (15 mg given p.o. q 6 h x 6 doses). Levamisole 50 mg p.o. t.i.d. on days 1-3, every 14 days for 6 months, was planned to be given in both arms. After a median follow-up of 4.2 years, 568 patients have relapsed and 403 have died. Survival was similar with MTX --> FU and FU+LV (77 vs 77% at 5 years; P = 0.90), as were 5-year disease-free survivals (67 vs 63%; P = 0.44). Efficacy results were similar for both stage III and II patients. There were two toxic deaths, two in the MTX --> FU arm (0.2%) and zero in the control arm. We conclude that biochemical modulation of FU with LV or with MTX produces similar results in the adjuvant setting of colon cancer.

In Asians, the risk of irinotecan-induced severe toxicities is related in part to UGT1A1*6 (UGT, UDP glucuronosyltransferase) and UGT1A1*28, variant alleles that reduce the elimination of SN-38, the active metabolite of irinotecan. We prospectively studied the relation between the UGT1A1 genotype and the safety of irinotecan-based regimens in Japanese patients with advanced colorectal cancer, and then constructed a nomogram for predicting the risk of severe neutropenia in the first treatment cycle.

Dihydropyrimidine dehydrogenase (DPD) catabolises ∼85% of the administered dose of fluoropyrimidines. Functional DPYD gene variants cause reduced/abrogated DPD activity. DPYD variants analysis may help for defining individual patients' risk of fluoropyrimidine-related severe toxicity.

The phase II J003 (N = 169) and phase III RECOURSE (N = 800) trials demonstrated a significant improvement in survival with trifluridine (FTD)/tipiracil (TPI) versus placebo in patients with refractory metastatic colorectal cancer. This post hoc analysis investigated pharmacokinetic data of FTD/TPI exposure and pharmacodynamic markers, such as chemotherapy-induced neutropenia (CIN) and clinical outcomes.

The primary structure of nucleoside diphosphate (NDP) kinase II, one of the two isozymes found in spinach leaves, has been deduced from its cDNA sequence. NDP kinase II comprises 233 amino acid residues and has a molecular mass of 26,107 Da, which is larger than that of the purified NDP kinase II subunits (18 kDa) by about 8 kDa, suggesting that NDP kinase II might be post-translationally processed. Homology was found between the sequence of spinach NDP kinase II, and the sequences of spinach NDP kinase I, rat NDP kinases alpha and beta, Dictyostelium discoideum NDP kinase, the human Nm23-H1 and Nm23-H2 proteins and the awd protein of Drosophila melanogaster.

Human oxidation resistance 1 (OXR1) functions in protection against oxidative damage and its homologs are highly conserved in eukaryotes examined so far, but its function still remains uncertain. In this study, we identified a homolog (LMD-3) of human OXR1 in the nematode Caenorhabditis elegans (C. elegans). The expressed LMD-3 was able to suppress the mutator phenotypes of E. coli mutMmutY and mutT mutants. Purified LMD-3 did not have enzymatic activity against 8-oxoG, superoxide dismutase (SOD), or catalase activities. Interestingly, the expression of LMD-3 was able to suppress the methyl viologen or menadione sodium bisulfite-induced expression of soxS and sodA genes in E. coli. The sensitivity of the C. elegans lmd-3 mutant to oxidative and heat stress was markedly higher than that of the wild-type strain N2. These results suggest that LMD-3 protects cells against oxidative stress. Furthermore, we found that the lifespan of the C. elegans lmd-3 mutant was significantly reduced compared with that of the N2, which was resulted from the acceleration of aging. We further examined the effects of deletions in other oxidative defense genes on the properties of the lmd-3 mutant. The deletion of sod-2 and sod-3, which are mitochondrial SODs, extended the lifespan of the lmd-3 mutant. These results indicate that, in cooperation with mitochondrial SODs, LMD-3 contributes to the protection against oxidative stress and aging in C. elegans.