Disturbance of systemic antioxidant profile in non-small cell lung carcinoma

¹ University Depts of Medicine
² Diagnostic Radiology
³ Pathology, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China

^* To whom correspondence should be addressed. E-mail: jcmho{at}netvigator.com.

	Abstract

This study aimed to determine the alterations of antioxidant activities in erythrocytes from patients with non-small cell lung carcinoma (NSCLC).

We conducted a comparative study of the systemic antioxidant activities in red blood cell lysate from subjects with NSCLC and healthy control subjects. Antioxidants (catalase, superoxide dismutase [SOD], and glutathione peroxidase [GPx]) were measured using chemical kinetic reactions under spectrophotometry.

There were 189 cases of mostly advanced stage IIIB or IV NSCLC and 202 healthy controls being studied. In subjects with lung cancer, there were similar catalase activity, lower SOD activity (median [interquartile range]: 13.4 [9.0, 27.2] vs 48.7 [27.0, 64.3] U·gHb^-1, p<0.001), and higher GPx activity (median [interquartile range]: 175.2 [126.6, 288.3] vs 49.2 [39.5, 59.2] mU·gHb^-1, p<0.001) compared with controls. The antioxidant activities in lung cancer subjects were not associated with age, gender, smoking status, or tumour cell types. However, more advanced disease (stage IV compared to IIIB) was associated with lower SOD activity. Using multivariable analysis, the presence of lung cancer independently predicts SOD and GPx activities.

In conclusion, NSCLC in Chinese is associated with alterations in systemic antioxidant activities, which may play an important role in carcinogenesis.