AOSP21 GENETIC POLYMORPHISMS OF DRUG-METABOLISING ENZYMES AND CHEMOTHERAPY RESISTANCE IN PATIENTS WITH LYMPHOPROLIFERATIVE DISEASES

Abstract

s, 5th AOS and 9th Annual Conference of OOTR, 2013 / European Journal of Cancer 49S1 (2013) S1−S22 S13 AOSP19 ANTIMETASTATIC EFFECTS OF DIETHYLDITHIOCARBAMATE ON CHOLANGIOCARCINOMA CELLS P. Srikoona, R. Kariyaa, K. Vaeteewoottacharna,b, E. Kudoa, H. Gotoa, M. Tauraa, S. Wongkhamb, S. Okadaa *. aDivision of Hematopoiesis, Center for AIDS Research, Kumamoto University, Kumamoto, Japan, bDepartment of Biochemistry, Faculty of Medicine and Liver Fluke and Cholangiocarcinoma Research Center, Khon Kaen University, Khon Kaen, Thailand Introduction. Cholangiocarcinoma (CCA) is a malignant tumour of biliary ductswith poor prognosis andhighmortality rate. Highly constitutive activated transcription factor nuclear factor uB (NF-uB) is found generally in CCA cells. NF-uB is well known to play roles in different tumour genesis processes. Diethyldithiocarbamate (DDTC) has been reported to inhibit the NF-uB pathway, inducing cancer cell apoptosis. However, the effects of DDTC on cancer cell metastasis have not reported yet. Methods. Human CCA cell lines (KKU-M213, KKU-M214, and KKU-OCA17) were used to screen the inhibition of cell viability by DDTC treatment. Inhibitions of cell metastasis were performed using the KKU-M213 cell line. Cells treated with DDTC were compared with untreated (control) samples. Antimigration activities were investigated by wound healing assay and Transwell assay. Cell adhesion was observed by adhesion assay. NF-uB transcriptional activity was investigated by luciferase assay. Protein-DNA binding affinity was determined by electrophoresis mobility shift assay (EMSA). Western blot analysis was analysed to determine NF-uB protein levels. The levels of mRNA expression of NF-uB target genes related to cancer cellmetastasiswere determined by quantitative real-time PCR. Results. DDTC inhibited cell migration and adhesion in KKU-M213 cells in dose-dependent and time-dependent manners. Luciferase assay indicated that DDTC inhibit NF-uB transcriptional activity. The protein-DNA binding affinity was clearly suppressed, while protein levels showed the attenuated active p65 with DDTC treatment. The strong suppressionof intercellular adhesionmolecule-1 (ICAM1) gene expression suggested that CCA cell adhesion was inhibited by DDTC via the inhibition of NF-uB pathway. Discussion. These findings suggest that DDTC has an antimetastatic effect on CCA cells through the suppression of the NF-uB signalling pathway, which suggests therapeutic potential against human CCA metastasis. Funding. Grants-in-Aid for Science Research (No. 23107725) from the Ministry of Education, Science, Sports, and Culture of Japan. The authors declared no conflicts of interest. AOSP20 Abstract withdrawn AOSP21 GENETIC POLYMORPHISMS OF DRUG-METABOLISING ENZYMES AND CHEMOTHERAPY RESISTANCE IN PATIENTS WITH LYMPHOPROLIFERATIVE DISEASES E. Gorbachenkoa *, O. Gorevaa, A. Grishanovaa, E. Vigovskayab. aInstitute of Molecular Biology and Biophysics, Siberian Branch of the Russian Academy of Medical Sciences, Novosibirsk, Russian Federation, bMunicipal Clinical Hospital No. 2, Hematology Center, Novosibirsk, Russian Federation Introduction. One of the molecular mechanisms of multidrug resistance may be xenobiotic metabolism, including anticancer drugs. Cytochromes P450 (CYPs) and glutathioneS-transferases (GSTs) are important enzymes of phase I and phase II xenobiotic metabolism, respectively. CYPs and GSTP1 genes are polymorphic and can underlie the individual reactions of patients to chemotherapy. Our study analysed the association of functionally significant gene polymorphisms with chemotherapy resistance in patients with lymphoproliferative diseases. Methods. We determined CYP2C8*2, CYP2C8*3, CYP2C9*2, CYP2C9*3, CYP2C19*2, CYP2C19*3, CYP3A5*3, GSTP1 313A→G and GSTP1 341C→T genetic polymorphisms in blood samples of 79 patients (mean age 57 years, SD 13) with lymphoproliferative diseases (non-Hodgkin lymphoma, chronic lymphocytic leukaemia) by PCR-RFLP assays. All patients received chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisolone). The odds ratio (OR) was used to estimate association of CYP genotypes with chemotherapy resistance risk and was calculated for the combined group (mutant homozygous and heterozygous) in comparison with the wild genotype group. Results.Wehave found the followingmutant allele frequencies in patients with chronic lymphoproliferative diseases: CYP2C8*2, 0.00; CYP2C8*3, 0.14; CYP2C9*2, 0.11; CYP2C9*3, 0.05; CYP2C19*2, 0.13; CYP2C19*3, 0.00; CYP3A5*3, 0.93; GSTP1 313A→G, 0.21; and GSTP1 341C→T, 0.12. Patients were divided in two groups according to the response to chemotherapy: effect was estimated as positive (n=57) in cases of complete or partial remission or stabilisation and as negative (n=22) in cases of progression of disease. The risk of resistance to chemotherapy for patients had one or two CYP2C8*3 or CYP2C9*2 allele was 7.05-fold significantly (p=0.002) and 4.1fold significantly (p=0.02) higher than for wild genotype carriers, respectively. There were no significant associations of CYP2C9*3 (OR 0.85, p=0.99), CYP2C19*2 (OR 0.88, p=0.99), CYP3A5*3 (OR 1.58, p=0.72), GSTP1 313A→G (OR 1.38, p=0.74), and GSTP1 341C→T (OR 1.21, p=0.97) genetic polymorphisms with chemotherapy response. Discussion. Our results suggest that CYP2C8*3 and CYP2C9*2 polymorphisms are associated with chemotherapy resistance in patients with lymphoproliferative diseases. Funding. None declared. The authors declared no conflicts of interest.