Thymidylate SynthaseFolic Acid AntagonistsThiophenesFluorodeoxyuridylateDeoxyuracil NucleotidesTrimetrexateThymidine MonophosphateTetrahydrofolate DehydrogenaseTetrahydrofolatesFloxuridineAntimetabolites, AntineoplasticFolic AcidAminopterinMethotrexateQuinazolinesDihydrouracil Dehydrogenase (NADP)Polyglutamic AcidReduced Folate Carrier ProteinFluorouracilIsoindolesGlutamatesLeukemia L1210DeoxyuridineLactobacillus caseiGuanineNucleoside-Phosphate KinasePteroylpolyglutamic AcidsFormyltetrahydrofolatesDrug ResistancePhosphoribosylglycinamide FormyltransferaseHydroxymethyl and Formyl TransferasesFolate Receptors, GPI-AnchoredPhosphoribosylaminoimidazolecarboxamide FormyltransferaseProguanilThymidineLeucovorinMethyltransferasesPeptide SynthasesThymidine PhosphorylaseEnzyme InhibitorsThymine NucleotidesTumor Cells, CulturedDihydropteroate SynthaseKineticsMolecular Sequence DataRNA, MessengerGlycine HydroxymethyltransferaseOrotate PhosphoribosyltransferaseColonic NeoplasmsColorectal NeoplasmsCitrate (si)-Synthasegamma-Glutamyl HydrolaseDrug Resistance, NeoplasmBase Sequence