1 / 37

Pharmcogenetics in oncology

Pharmcogenetics in oncology. Pierre Laurent-Puig INSERM, U775 Molecular basis of xenobiotic response AP-HP H ôpital Européen Georges Pompidou Molecular Oncology and Pharmacogenetic laboratory. Introduction. Multiple active regimens for cancer but:

ivy
Download Presentation

Pharmcogenetics in oncology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Pharmcogenetics in oncology Pierre Laurent-Puig INSERM, U775 Molecular basis of xenobiotic response AP-HP Hôpital Européen Georges Pompidou Molecular Oncology and Pharmacogenetic laboratory

  2. Introduction • Multiple active regimens for cancer but: • Variation in response rate to the different regimen • Unpredictable toxicity for the different regimens • With choice came the time to decision • Need to the development of tools which help clinicians

  3. Pharmacogenetics Anticancer drugs Genetic factors Environmental factors Variations in drug response or toxicity Transport Metabolism Drug target Cell Drug interactions Lee et al. Oncologist. 2005;10:104-111.

  4. Introduction • Pharmacogenetics : the science of incorporating information of inherited genetic variability into predicting treatment response. • Polymorphisms in both individual’s genome as well as tumor genome will affect drug toxicity and drug response. • Drug-related toxicity will be predicted mainly by genotyping non tumour tissues. • Drug response will be predicted both by genotyping non tumour and tumour tissues.

  5. 5-FU Pathway Capecitabine FBAL Carboxyl esterase -ureidopropionase 5’dFCR Cytidine deaminase FUPA 5’dFUR (Uracil misincorporation) DNA Thymidinephosphorylase Dihydropyrimidinase 80%-90% Tegafur 5-FU DHFU 5-MTHF dUTP Dihydropyrimidine dehydrogenase Uridine phosphorylase Methylene tetrahydrofolate reductase Thymidine phosphorylase dUTPase dUDP 5F-uridine 5F-deoxyuridine Orotate phosphoribosyl transferase Thymidine kinase dUMP 5, 10-MTHF Uridine kinase Serine hydroxymethyl transferase Thymidylate synthase 5-FUMP FdUMP THF Uridine monophosphate kinase Uridine monophosphate kinase dUTPase Dihydrofolate reductase DHF dTMP dTDP FdUDP FdUTP Folinic acid (leucovorin) 5-FUDP Ribonucleotide reductase Uridine diphosphate kinase Uridine diphosphate kinase dTTP 5-FUTP DNA

  6. DPD and 5-FU toxicity • IVS14+1G>A Polymorphism leads to the skipping of exon 14. • As a result, the mature DPD mRNA lacks a 165 nucleotide segment encoding amino acids 581–635 • Prevalence of IVS14+1G>A 0.75% to 2.2% van Kuilenburg et al. Eur J Cancer. 2004;40:939-950.

  7. 5-FU Toxicity and the Prevalence of IVS14 + 1G>A Mutations IVS14 + 1G>A Total group DPD ≤ 70% DPD > 70% Patients (n = 60) Heterozygotes Homozygotes 16 (27%) 1 (2%) 15 (42%) 1 (3%) 1 (4%) 0 Patients (n = 25) Heterozygotes Homozygotes 5 (20%) 1 (4%) n.d. n.d. n.d. n.d. • 24-29% of patients with grade 3-4 5-FU toxicity were heterozygous or homozygous for the IVS14 + 1G>A mutation • Almost half of the patients with decreased DPD activity were carriers of the IVS14 + 1G>A mutation • Applying Bayes’ theorem we can estimate the risk of 5-FU grade 3-4 toxicity for a carrier of IVS14+1G>A mutation to 87% van Kuilenburg et al. Eur J Cancer. 2004;40:939-950; van Kuilenburg et al. Pharmacogenetics. 2002;12:555-558; Raida et al. Clin Cancer Res. 2001;7:2832-2839.

  8. 5-FU Toxicity and the Prevalence of DYPD polymorphism 14 IVS14 + 1G>A Exon 14 skipping; 2846A>T, D949V; 1679T>G,I560S Sensitivity, specificity, and PPV and NPV of the detection of these three major SNPs as toxicity predictive factors were 0.31, 0.98, and 0.62 and 0.94, respectively. Morel A. Mol Cancer Ther 2006:5:2895-904.

  9. Functional consequences In vitro studies demonstrated that an increasing number of tandem repeats leads to an increase in TS gene expression and TS enzyme activity The SNP in the second repeat of the 3R allele disrupts the upstream stimulatory factor (USF) consensus element and therefore decreases the in vitro transcriptional activation of TS The TS 3’UTR del6 allele may determine low TS mRNA stability and low TS expression in comparison with TS 3’UTR ins 6 allele TS Polymorphisms Polymorphisms • One in the enhancer region of TS consisting in a double or triple repeat of a 28-base pair sequence (2R or 3R) • G>C SNP in the second of the three 28-bp repeats produces two additional alleles (3RG or 3RC) • One in the 3’UTR region consisting of an insertion or a deletion of 6 bp Desai et al. Oncogene. 2003;22:6621-6628.

  10. 5-FU Toxicity (all) and Polymorphism of TS Gene Promoter in CRC N = 86 CRC patients 5-FU based chemotherapy % (6/14) • TS promoter genotype is predictive of grade 3/4 toxicities with 5-FU • 3R/3R genotype, over-expressing TS, has fewer toxicities • No association with a response to 5-FU and survival Grade 3 / 4 toxicities (%) (8/44) % (1/28) % (49%) (31%) (16%) P = 0.02 Lecomte et al. Clin Cancer Res. 2004;10:5880-5888. * 2R/2R vs 2R/3R, 3R/3R

  11. E428A MTHFR Polymorphisms A222V • Two polymorphisms may alter enzyme activity • 677C->T (Ala222Val) increases MTHFR thermolability • 1298A->T (Glu428Ala) decreases MTHFR activity • Since a loss in MTHFR enzymatic activity may favor an increase in intracellular CH2FH4 concentrations, it can be hypothesized that tumors exhibiting mutated MTHFR genotypes may be more sensitive to 5-FU cytotoxicity.

  12. MTHFR Polymorphisms & Clinical Outcomes

  13. MTHFR and 5-FU response 219 patients with advanced colorectal cancer receiving 5-FU *unadjusted OR Cohen et al. Clin Cancer Res 2003;9:1611-1615; Etienne et al. Pharmacogenetics 2004;14:785-792; Jakobsen et al. J Clin Oncol. 2005;23:1365-1369.

  14. Two types of colorectal cancer Tumor LOH + (85%) Tumor MSI + (15%) •Hyperploid •Diploid •Recurrent allelic losses on chromosomes 17p, 18q, 5q, 8p, 22q •No allelic losses on chromosome 17p, 18q, 5q, 8p, 22q •Frequent p53 and APC gene mutations •Rare p53 and APC gene mutations •Frequent BRAF and PIK3CA gene mutations •Frequent KRAS and PIK3CA gene mutations •Frequent mutation of TGFß receptor type II, Caspase 5, Bax and TCF4 genes •Up to 20 different genes were found mutated •Alteration of MLH1 MSH2, MSH6 and MSH3 genes •Mainly in distal colon •Mainly in proximal colon Chromosomal instability Paradigm: FAP tumors owing to germline mutation of APC gene Genetic instability Paradigm: HNPCC tumors owing to germline mutation of MMR genes

  15. Role of MSI status in adjuvant 5FU treatment response Treatment overall suvival % Control MSS tumours Control Treatment MSI tumours overall suvival % A significant interaction was observed between microsatellite instability status and the benefit of treament p=0.01 Ribic et al N Engl J Med 2003; 349:247-57.

  16. P-gp ABCB1 CES2 CES2 APC CYP3A4 CYP3A5 NPC SN-38G ABCB1 P-gp death CPT-11 TOPI SN-38 SN-38 SN-38 Irinotecan Pathway CPT-11 CPT-11 UGT1A1

  17. UGT1A1 promoter polymorphisms Promoter Exons UGT1A1 (TA)6 TAA Variant (TA)7 TAA Normal gene expression Decrease gene expression Low glucuronidation leads to 1.8 to 3.9 fold lower glucuronidation of SN-38 Normal glucuronidation Iyer et al. Pharmacogenomics J. 2002;2:43-47.

  18. Published Data on UGT1A1 & grade 4 neutropenia

  19. UGT1A1 promoter genotype and Irinotecan toxicity (in combination) • 400 patients with high risk stage III colorectal cancer included in a randomised trial FNCLCC Accord02 / FFCD9802 comparing LV5FU2 alone versus Folfiri regimen. • FOLFIRI regimen • Irinotecan 180mg/m2, 90 min iv day 1 • Leucovorin 200mg/m2 during irinotecan day 1 • 5FU 400mg/m2 iv bolus followed by 2400mg/m2, during 46 hours • Clinical evaluation • Toxicity • Survival • UGT1A1 TA6/TA7 and -3156 G->A polymorphisms were studied in 94 patients receiving FOLFIRI

  20. Hematological toxicity grade 3-4 according to UGT1A1 genotypes TA6>TA7 -3156G>A p=0.15 p=0.02

  21. Survival without grade 3-4 hematological toxicity (-3156G>A) Proportion of patient without hematological grade 3-4 toxicity p=0.012 Number of cycles Côté et al. Clinical Cancer Res accepted

  22. Response to chemotherapy WHO and UGT1A1 *28 polymorphism (n=238) Toffoli presentation the ASCO GI Meeting in January 2006

  23. Oxaliplatin Pathway Extracellular Platinum Cell membrane Intracellular ABCG2 ABCC2 Detoxify GSTM1 NQO1 Platinum GSTP1 MPO SLC31A1 SOD1 Platinum ATP7A Translesional replication POLB POLH Platinum Pt G G Platinum HMGB1 ERCC1 Damage recognition XPA XRCC1 ERCC2 MLH1 MSH6 Excision repair Mismatch repair Cell death

  24. GSTP1 Polymorphisms I105V A114V • Two non synonymous coding polymorphisms • Single nucleotide polymorphism (SNP) at residue 105 Ile105Val substitution (39%) • Single nucleotide polymorphism (SNP) at residue 114 Ala114Val (12%) • Four haplotypes *A Ile105+Ala114; *B Val105+Ala114; *C Val105+Val114; *D Ile105+Val114 • Variability in enzymatic activities depending of the substrate • Lower thermal stability for the 105 Val allele • Variability in detox properties according to the haplotypes Ishimoto TM, Ali-Osman F. Pharmacogenetics 2002;12:543-553.

  25. GSTP1 Polymorphisms & Clinical Outcomes

  26. GSTP1, Oxaliplatin and survival 107 patients with metastatic colorectal cancer who received 5-FU/oxal VAL/VAL (n=10) ILE/VAL (n=45) ILE/ILE (n=45) P < 0.001 After adjustment for performance status the relative risk of dying for patients with ILE/VAL and ILE/ILE genotypes was 2.73 and 3.25 respectively P = 0.072 Stoehlmacher et al. JNCI. 2002;94:936-941; Stoehlmacher et al. Br J Cancer. 2004;94: 944-954.

  27. ERCC1 polymorphism N118N • ERCC1 codes for a protein in the nucleotide excision repair pathway • High ERCC1 level is associated with resistance to oxaliplatin • Polymorphism in codon 118 is silent • 118 TT genotype is associated with reduced translation of the gene, and presumably reduced DNA repair capability (ovarian cancer cell lines). But in colon cancer, patients with ERCC1 118 TT genotype have a higher expression of ERCC1 mRNA.

  28. ERCC1 Polymorphisms & Clinical Outcomes 2 studies with conflicting results: • Stoehlmacher et al. Br J Cancer 2004;94: 944-54 • 107 metastatic colorectal cancer patients receiving oxaliplatin plus 5FU • Relative risk of dying was 2.05, 95%CI [1.00-4.20] forCTand TT genotypes as compared to CC genotype patients • Viguier et al. Clin Cancer Res 2005;11:6212-7 • 61 metastatic colorectal cancer patients receiving FOLFOX regimen • The objective response rate was 21.4% , 42.3% and 61.9% for CC, CT and TT genotypes

  29. Summary

  30. TK TK TK EGFR pathways EGF ligands TGF Dimerisation membrane P EGFR Phosphorylation = Activation P Resistance to apoptosis angiogenesis proliferation Bad, caspase 9 VEGF, IL8 Cycline D1

  31. membrane P P TK TK P P ERK ERK Ras/MAPK pathways hSos Ras Raf Grb GTP P MEK MEK Intracellular phosphorylation cascade (Raf, Erk, Mek) = MAP Kinases Serine/Threonine Kinases ERK P C-MYC, JUNB, c-JUN cycline D1 cdk6  c-fos P phase G1 cell cycle nucleus

  32. membrane P P P TK TK PI3K/Akt pathways Phosphatidyl-inositol PI 3,4,5-P3 PI3K Pdk1 Pdk2 PI3K Akt Akt P P - - P P Activation of eIF-4E inhibition of 4E-BP1 S6 kinase Bad, caspase-9, Fkhrl-1 Gsk3 Stabilisation of Cyclin D1 Resistance to apoptosis Cell cycle G1 transition Protein synthesis 

  33. Response to Cetuximab • 30 patients treated by cetuximab for a stage IV colorectal cancer • 3 in first line with folfiri • 3 in second line • 24 in third line • 11 responders (1 with complete response ) • Sequencing of KRAS (ex1), BRAF (ex11&15), PIK3CA (ex1,ex2, ex9, ex11) • Measure of EGFR amplification by CISH (F.Penault-Llorca) Lievre et al. Can Res 2006;66:3992-5

  34. Prevalence of alterations • KRAS is mutated in 13 cases (48%) • 10 cases at codon 12 • 3 cases at codon 13 • PIK3CA is mutated in 2 cases (7%) • 2 cases in exon 9 • these 2 tumours are also mutated for KRAS • BRAF is not mutated • EGFR is amplified in 3 cases • >20 copies in 1 case • >10 copies in 2 cases

  35. Response rate to cetuximab therapy according to KRAS mutation P=0.0003 Lievre et al. Can Res 2006;66:3992-5

  36. Overall survival according to KRAS mutation for patients treated with cetuximab Lievre et al. Can Res 2006;66:3992-5

  37. Conclusions • Molecular predictive factors of response to chemotherapy for colorectal cancer patients have been identified • From the host or from the tumor • From different pathways • Xenobiotic metabolizing enzyme , Drug target • It is time to study more than one predictive factor at the same time in order to choose the best • The development of “omic” approaches will allow the “a la carte” treatment of cancer patient with the most efficient and the less toxic drugs

More Related