8-oxo-7-8-dihydrodeoxyguanine and Colorectal-Neoplasms

Oxidative stress linked with chronic inflammation is associated with etiology of the colorectal cancer.. To assess the diagnostic utility of urinary excretion of oxidatively modified DNA bases/nucleoside: 8-oxo-7,8-dihydroguanine (8-oxoGua), 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) and 5-hydroxymethyluracil (5-hmUra).. Seventy-two healthy controls, 15 patients with adenomas and 56 colorectal cancer patients were recruited.. The receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) for all markers tested separately was <0.7. The combination of these modifications showed better diagnostic power (AUC = 0.778 for 8-oxoGua + 8-oxodG)/5hmUra ratio).. Urinary DNA modifications may reflect the oxidative stress/chronic inflammation in colorectal cancer but diagnostic performance for early-detection is moderate.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aged; Biomarkers, Tumor; Colorectal Neoplasms; Female; Guanine; Humans; Male; Middle Aged; Pentoxyl

This study investigated the connection among the oxidative stress, depression and expression of specific genes involved in DNA-damage signaling pathways in patients with colorectal carcinoma (CRC).. A unique Dukes'C subset of patients with newly diagnosed colorectal adenocarcinoma were assessed using the Hamilton Depression Rating Scale (HAMD), Zung Self-rating Depression Scale (SDS), Zung Self-rating Anxiety Scale (SAS), Symptom Checklist 90 (SCL-90) and other multiple-item questionnaires. Oxidative-stress-related parameters in sera and the expression of genes were monitored during a pretreatment period.. Eighty-two eligibility cases were divided into 2 groups based on an HAMD score cutoff of 20: the mean score was 28.29 in Group A (depression, n=52) and 16.50 in Group B (nondepression, n=30). The serum total antioxidant capacity, catalase, and superoxide dismutase concentrations were lower in Group A, whereas those of nitric oxide and malondialdehyde were higher in Group A. Importantly, the 8-hydroxy-deoxyguanosine level was higher in Group A than in Group B (P<.05). Microarray analysis revealed that the expressions of p34, PA26, and ABL were higher in Group A, whereas those of HRAD51, CR6, and XRCC3 were higher in Group B.. Oxidative stress is capable of causing neuronal toxicity via lipid peroxidation, DNA damage, and abnormalities of gene expression, and therefore is a possible pathogenic mechanism underlying depression in patients with CRC.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenocarcinoma; Adult; Aged; Colorectal Neoplasms; Depressive Disorder; DNA Damage; Female; Gene Expression Regulation, Neoplastic; Guanine; Humans; Male; Middle Aged; Neoplasm Staging; Oligonucleotide Array Sequence Analysis; Oxidative Stress; Personality Inventory; Psychometrics; Reverse Transcriptase Polymerase Chain Reaction; Risk Factors; Signal Transduction

To clarify the role of oxidative stress in aging of colorectal tissue, we analyzed the 8-hydroxydeoxyguanosine (8-OH-dG) levels in colorectal biopsy samples from normal tissue of patients with either colorectal cancer (n = 15) or benign colorectal polyps (n = 40). An age-associated increase of 8-OH-dG was observed (p =.002), although the 8-OH-dG levels were not significantly different between the patients with cancer and those with polyps. These results suggest an increased level of 8-OH-dG formation in human colorectal tissue with age.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aged; Aged, 80 and over; Aging; Colon; Colonic Polyps; Colorectal Neoplasms; DNA; Guanine; Humans; Intestinal Polyps; Middle Aged; Oxidative Stress; Rectum