Expression of Hsp27 and Hsp70 in lymphocytes and plasma in healthy workers and coal miners with lung cancer

Abstract

In coal mines, main occupational hazard is coal-mine dust, which can cause health problem including coal workers' pneumoconiosis and lung cancer. Some heat shock proteins (Hsps) have been reported as an acute response to a wide variety of stressful stimuli. Whether Hsps protect against chronic environmental coal-mine dust over years is unknown. It is also interesting to know that whether the expression of Hsp27 and Hsp70 proteins as a marker for exposure is associated risk of lung cancer among coal miners. We investigated the association between levels of Hsp27 and Hsp70 expression in lymphocytes and plasma and levels of coal-mine dust exposure in workplace or risk of lung cancer in 42 cancer-free non-coal miners, 99 cancer-free coal miners and 51 coal miners with lung cancer in Taiyuan city in China. The results showed that plasma Hsp27 levels were increased in coal miners compared to non-coal miners (P<0.01). Except high cumulative coal-mine dust exposure (OR=13.62, 95%CI=6.05-30.69) and amount of smoking higher than 24 pack-year (OR=2.72, 95% CI=1.37-5.42), the elevated levels of plasma Hsp70 (OR=13.00, 95% CI=5.14-32.91) and plasma Hsp27 (OR=2.97, 95% CI=1.40-6.32) and decreased expression of Hsp70 in lymphocytes (OR=2.36, 95% CI=1.05-5.31) were associated with increased risk of lung cancer. These findings suggest that plasma Hsp27 may be a potential marker for coal-mine dust exposure. And the expression of Hsp27 and Hsp70 levels in plasma and lymphocytes may be used as biomarkers for lung cancer induced by occupational coal-mine dust exposure.