Background PM 2.5 is associated with increased risk of mortality for a variety of cancers and all subjects, including breast cancer in females, and lung cancer in males. This study investigates the effects of waterextracted PM 2.5 on a triple-negative breast cancer (TNBC) cell line, MDA-MB-231, by sampling suspended particulates around a building demolition site. Methods PM 2.5 particles were obtained using a high-flow TISCH sampler. Being water-soluble, they were extracted from sampled filters using an ultrasonic oscillator and then freeze-dried. The heavy metal components of soluble PM 2.5 particle was analyzed by ICP-MS. Cell viability was evaluated by MTT assay for cells that were exposed to PM 2.5. Wound healing and transwell cell migration and invasion assays were used to measure cell motility and the invasiveness of cancer cells that had been exposed to PM 2.5 into a chemo-attractant substance. Possible mechanisms of cancer malignancy were analyzed by Western blot analysis. Results The results revealed that nearby PM 2.5 concentrations increased significantly during the deconstruction of buildings, and the Cd, Cu, Pb, Zn and Cr contents of soluble PM 2.5 also significantly increased. Following exposure to PM 2.5 , the survival rate of breast cancer cells was significantly higher than that of the control group. Soluble PM 2.5-treated cells also had a higher migration capacity, as determined by wound healing and transwell migration assays. The signaling pathway of FAK/PI3K/AKT proteins was more activated in PM 2.5-treated cells than the control group. The data show that increased levels of Aurora B and Bcl-2 were associated with cell proliferation. Elevated levels of cathepsins D, β-catenin, N-cadherin, vimentin and MMP-9 were associated with breast cancer cell metastasis Conclusion Soluble PM 2.5 that is generated in building demolition may have a role in the promotion/progression of

Background PM 2.5 is associated with increased risk of mortality for a variety of cancers and all subjects, including breast cancer in females, and lung cancer in males. This study investigates the effects of waterextracted PM 2.5 on a triple-negative breast cancer (TNBC) cell line, MDA-MB-231, by sampling suspended particulates around a building demolition site.Methods PM 2.5 particles were obtained using a high-flow TISCH sampler. Being water-soluble, they were extracted from sampled filters using an ultrasonic oscillator and then freeze-dried. The heavy metal components of soluble PM 2.5 particle was analyzed by ICP-MS. Cell viability was evaluated by MTT assay for cells that were exposed to PM 2.5 . Wound healing and transwell cell migration and invasion assays were used to measure cell motility and the invasiveness of cancer cells that had been exposed to PM 2.5 into a chemo-attractant substance. Possible mechanisms of cancer malignancy were analyzed by Western blot analysis. ResultsThe results revealed that nearby PM 2.5 concentrations increased significantly during the deconstruction of buildings, and the Cd, Cu, Pb, Zn and Cr contents of soluble PM 2.5 also significantly increased. Following exposure to PM 2.5 , the survival rate of breast cancer cells was significantly higher than that of the control group. Soluble PM 2.5 -treated cells also had a higher migration capacity, as determined by wound healing and transwell migration assays. The signaling pathway of FAK/PI3K/AKT proteins was more activated in PM 2.5 -treated cells than the control group. The data show that increased levels of Aurora B and Bcl-2 were associated with cell proliferation. Elevated levels of cathepsins D, β-catenin, N-cadherin, vimentin and MMP-9 were associated with breast cancer cell metastasis Conclusion Soluble PM 2.5 that is generated in building demolition may have a role in the promotion/progression of 3 surviving in TNBC cells, increasing the malignancy of breast cancer. The prevention of environmental PM 2.5 from deconstruction is strongly recommended.