Effect of low dose arsenious acid combined with total particulate matter of cigarette smoke on oxidative stress in human lung cancer cell line A549 / 公共卫生与预防医学

Objective To investigate the effect of low-dose arsenious acid solution (As(III)) combined with total particulate matter (TPM) from cigarette smoke on cellular oxidative stress in human lung cancer cell line A549 cells. Methods A549 cells were divided into four groups: negative control group (0.75% DMSO), low dose As(III) group (0.88% μg/mL, 75% DMSO), cigarette smoke TPM group (75 μg/mL), and combined exposure group (75 μg/mL TPM, 0.88 μg/mL As (III)). After 24 hours' exposure, the superoxide dismutase (SOD) level in cell culture medium and intracellular 8-hydroxy-2-deoxyguanosine (8-OHdG) content were detected by ELISA, and intracellular reactive oxygen species (ROS) level was detected by fluorescent probe DCFH-DA. 2×2 factorial design was used to evaluate the interaction. Results Compared with the control group, the level of SOD in the combined exposure group was significantly increased (P<0.05). In addition, the ROS content in the combined exposure group and TPM alone group was significantly increased (P<0.05). The levels of 8-OHdG in the combined exposure group and low-dose As(III) treated group were significantly higher than those in the control group(P<0.05). The results of the factorial analysis showed that low-dose As(III) and TPM had interaction on SOD levels, ROS and 8-OHdG contents in A549 cells. The effects on SOD and ROS were synergistic, while the effect on 8-OHdG was antagonistic. Conclusion Low-dose arsenious acid solution As(III) and TPM in cigarette smoke have interaction on oxidative stress in A549 cells.

Research progress in cell transformation test and its application in cigarette smoke evaluation / 公共卫生与预防医学

In order to understand the current development of cell transformation assay (CTA) and its application in the evaluation of cigarette smoke carcinogenesis, the relevant literatures were analyzed and combed from these two aspects. CTA can evaluate the carcinogenicity of various genotoxic and non-genotoxic carcinogens in a short period of time, and has a strong consistency with the results of animal carcinogenic test. After malignant transformation, the cells show changes in cell morphology, immortalization of cells, disappearance of cell-cell contact inhibition, and the ability to form tumors when injected into animals. The identification methods of transformed cells include transformed cell focus count, agglutination test, soft agar culture and inoculation of nude mice, etc. At present, BALB/c 3T3 cells, Bhas 42 cells and SHE cells are the most widely used cells for CTA. Cigarette smoke is a complex aerosol containing a variety of non-genetic carcinogenic chemicals. Cell transformation tests are often used as an in vitro alternative method to evaluate the carcinogenic effects of cigarette smoke, which is different from the short-term genetic toxicity test. It simulates the long-term state of human smoking induced malignant transformation of cells, through the long-term exposure of cells for several decades, which is closer to the occurrence of cancer caused by human smoking. Therefore, CTA can evaluate the carcinogenicity of cigarette smoke and other tobacco products.