The level of oxidative stress and the expression of genes involved in DNA-damage signaling pathways in depressive patients with colorectal carcinoma.

OBJECTIVES

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).

METHODS

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.

RESULTS

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.

CONCLUSION

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.