Plasma Level Of Heavy Metal In Non-small-cell Lung Cancer And Pb Toxicity On Bronchial Epithelial Cell

Background:Heavy metal had been confirmed as carcinogens by the World Health Organization(WHO)'s international agency for research on cancer.They induce oxidative stress,produce inflammatory factors and influence metabolisms which could participate in the progression of cancer.some researches have comfirmed that chormium,cadmium and arsenic lead human bronchial epithelial cell(BEAS-2B cell)achieving tumorigenic ability.At present,there is no study on correlation among heavy metal,inflammatory factors and homocysteine(HCY).Further more there is no report about Pb can lead BEAS-2B cell achieving tumorigenic ability.Objective:To investigate the association of plasma heavy metal(Pb and Cd),inflammatory factors and homocysteine in non-small-cell lung cancer and further to explore their significance in the development in the carcinoma of lung.To explore whether the chronic lead exposure can induce inflammatory response and promote malignant transformation for bronchial epithelial cell.Methods:1.We recruited patients with non-small-cell lung cancer attending the first people's Hospital of Foshan.A total of 58 subjects has been collected,including 10 subjects in the stage of ???cancer,22 subjects in the stage of ? cancer,26 subjects in the stage of ?cancer.30 Control healthy subjects without chronic disease and without a history of direct contact with heavy metal were included.The levels of Pb and Cd were tested by Inductively coupled plasma mass spectrometry(ICP-MS).The concentration of inflammatory factors(IL-1??IL-8?COX-2?TNF-?)were tested by enzyme linked immunosorbent assay(ELISA).2.Chronic exposure of bronchial epithelial cells to lead BEAS-2B Cell has been studied.We found whether cells take acute toxicity under lead exposure by CCK-8 assay.Experimental cells were cultured with fresh medium of Pb for eight weeks.Cellular migration ability was assayed the cell scratch test.Tumorigenic ability of cells which were exposed to lead was quantified by soft-agar assays.Finally,expression of inflammatory cytokines was examined by RT-PCR and western Blotting.Results:1.Higher levels of Cd and Pb median(interquartile range)0.63(0.35?1.06)?g/L?42.04(22.34?91.62)?g/L were in patient with non-small-cell lung cancer compared with healthy controls 0.39(0.23?0.57)?g/L?17.91(8.92?23.16)?g/L(P<0.05).2.Higher levels of Cd and Pb were in smoker group and oldder group ompared with healthy controls(P<0.05).3.The concentration of median(interquartile range)IL-1?0(0.00?0.00)pg/mL?IL-8 20.94(0.00?57.67)pg/mL of the case group was higher than that of the control group 0.00(0.00?0.00)pg/mL?0.00(0.00?0.00)pg/mL(P<0.05).The concentration of COX-2 and TNF-? 14.08(11.91?17.20)ng/mL,35.84(22.52?44.99)pg/mL of the case group may be higher than that of the control group 12.63(11.33?14.33)ng/mL?27.84(23.23?34.21)pg/mL(P<0.1).4.The concentration of HCY of the case group mean±SD14.51±3.49 ?mol/L was higher than that of the control group 12.08±3.11?mol/L(P<0.05).5.The plasma Pb level positively correlated with the IL-8 and HCY levels.6.The levels of IL-8 and Pb were more abundant in the higher stage of lung cancer.7.BEAS-2B cells were cultured with different concentrations of medium(0?50?100?200?500?1000?g/L)of Pb for 24h in acute condition.We found that cells didn't have acute toxicity when cells under the medium at or below 100?g/L.It indicated that 100?g/L concentration of lead has little cute toxicity on BEAS-2B cells.Thus we determined to place the BEAS-2B cells under the 100?g/L concentration of Pb exposure for eight weeks for the long-term Pb chronic toxic effects.8.We found the cell activity increased when cells were exposed to 100ug/L concentration of Pb for 8 weeks compared with control group.However,there were no difference of cellular migration ability and tumorigenic ability between experimental group and control group.9.The protein and gene levels of IL-8 increased in the experimental group compared with control group.Conclusions:1.Heavy metal(Pb and Cd)and plasma inflammatory factors(IL-1??IL-8?COX-2?TNF-?)may play a significant role in the development of the lung cancer.2.Age and smoking might be the risk factors of heavy mental exposure.3.The exposure of Pb may increase the level of IL-8?HCY.4.We confirmed that chronic lead exposure for 8 weeks increased activity,cell number and the expression of IL-8 of lung epithelial cells,while chronic lead exposure had no effect on cellular migration ability and tumorigenic ability.