A study of glutathione status in the blood and tissues of patients with breast cancer

Abstract

Glutathione plays an important role in the antioxidant system that is required for the maintenance of the redox status of the cell, defence against free radicals and detoxification of toxic compounds. Reduced glutathione (redGSH) can be converted to oxidized glutathione (GSSG) during oxidative stress. The ratio of redGSH/total glutathione can be regarded as an index of the redox status and a useful indicator of disease risks. We conducted experiments by the capillary zone electrophoresis method to investigate the alterations of the glutathione status in the blood and tissue samples from patients with breast cancer. The results showed that the levels of redGSH, GSSG, total glutathione and the ratio of redGSH/total glutathione were significantly decreased in the blood of the patients with breast cancer compared to those of the control subjects. The levels of various forms of glutathione were lower and more pronounced in stage III. In contrast, the levels of redGSH, GSSG, total glutathione and the redGSH/total glutathione ratio in breast cancer tissues were significantly increased relative to those of the adjacent cancer-free tissues, especially in stage II. We suggest that the high redGSH levels are associated with the enhancement of cell proliferation and resistance to apoptosis in the cancer cells, and the loss of the large amount of erythrocyte redGSH may be due to increased detoxification capacities and defence against oxidative stress. We propose that redGSH should be regarded as an important biochemical parameter for detecting breast malignancy.

Suppressive Effects of Puerariae Radix on the Breast Tumor Incidence in Rats Treated with DMBA

“…A previous study indicated that elevated oxidative status arising from the imbalance between reactive oxygen species (ROS) and antioxidant systems played an important role in carcinogenesis (Wu, 2006), a finding consistent with other studies that observed increased oxidative stress in patients with breast cancer (Yeh et al, 2005(Yeh et al, , 2006. ROS are a family of molecules that include highly reactive free oxygen radicals produced in all cells during oxygen metabolism.…”

Connotation of Glutathione-S-Transferase Enzyme Expression (GST) and Glutathione (GSH) in Human Head and Neck Squamous Cell Carcinoma Cancer

“…The other plausible explanation for decreased levels of glutathione observed in head and neck cancer patients is possibly GSH, being exhausted as a main low molecular weight antioxidant in cellular protection [15,16]. Our results are in agreement with earlier studies which showed that levels of glutathione decrease in blood of the breast cancer when compared with control subjects [17].…”

Redox status expressed as GSH:GSSG ratio as a marker for oxidative stress in paediatric tumour patients

“…Oxidative stress causes profound alterations of various biological structures, including cellular membranes, lipids, proteins and nucleic acids. Oxidative stress is considered to be involved in ageing (14)(15)(16)(17)(18)(19)(20) Redox status expressed as GSH:GSSG ratio as a marker for oxidative stress in paediatric tumour patients (36)(37)(38)(39)(40)(41)(42)(43)(44). There is an increasingly growing interest in identifying biomarkers for diseases, in which oxidative stress is involved (45).…”