Cancer Care Engineering: Pilot Studies on Oxidative Damage and SNPs James E. Klaunig, PhD Barbara A. Hocevar, PhD Lisa M. Kamendulis, PhD Indiana University 1

Question: Is oxidative stress status altered in individuals with polyps or colorectal cancer? Approach Whole blood collected and processed for: – Comet Analysis (Direct and Oxidative DNA damage) – Total Antioxidant Capacity (TEAC) – Focused SNP analysis Samples: – 72 controls (16 noted a history of polyps) – 66 polyps – 32 colorectal cancer (including 7 return visits) SNPs evaluated only on samples from the initial visit What Modulates Oxidative Stress? Dietary and lifestyle influences high fat diet, alcohol, smoking, etc.  increased ROS levels decreased antioxidants  increased ROS levels Sources: Inflammation Immune Cells (including microglia) Endothelial Cells Mitochondria Peroxisomes Metabolism (P450) (Xenobiotics) Antioxidants GSH, Vitamin E, VitC, SOD, Catalase, etc Pro-oxidants H 2 O 2, O 2 -, HO, 1 O 2 2

Comet data (95 samples analyzed): TEAC Data (110 samples analyzed): Question: Is oxidative stress status altered in individuals with polyps or colorectal cancer? 3

Question: Do differences exist in SNPs for oxidative stress and damage, and selective genes associated with colorectal cancer? Oxidative Stress – Catalase – SOD2 – NOS3 – GSTP – GSTM1 DNA Damage/Repair – APEX1 – XRCC – OGG1 – TP53 Inflammation – IL-6 – IL-8 – PTGS2 (COX2) Vitamin D Status – VDR – CASR – CYP24A1 Metabolism – CYP1A2 – CYP3A4 SNPs evaluated (~120 samples analyzed) 4

Selected Examples: GSTM1 null shown to be protective, % null population decreases in colorectal cancer Polymorphism in promoter region of COX2 reported to change transcriptional activity. Not previously reported in colon cancer I64V amino acid change, function unknown. No differences observed in this population. 5

Next Steps Complete sample and data analysis Select additional SNPs based on initial statistical analysis 6