Signaling factors and pathways of α-particle irradiation induced bilateral bystander responses between Beas-2B and U937 cells

Publication date: Available online 2 May 2016 Source:Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis Author(s): Jiamei Fu, Juan Wang, Xiangdong Wang, Ping Wang, Jinping Xu, Cuiping Zhou, Yang Bai, Chunlin Shao Although radiation induced bystander effects (RIBE) have been investigated for decades for their potential health risk, the underlying gene regulation is still largely unclear, especially the roles of immune system and inflammatory response in RIBE. In the present study, macrophage U937 cells and epithelial Beas-2B cells were co-cultured to disclose the cascades of bystander signaling factors and intercellular communications. After α-particle irradiation, both ERK and p38 pathways were activated in Beas-2B cells and were associated with the autocrine and paracrine signaling of TNF-α and IL-8, resulting in direct damage to the irradiated cells. Similar upregulation of TNF-α and IL-8 was induced in the bystander U937 cells after co-culture with α-irradiated Beas-2B cells. This upregulation was dependent on the activation of NF-κB pathway and was responsible for the enhanced damage of α-irradiated Beas-2B cells. Interestingly, the increased expressions of TNF-α and IL-8 mRNAs in the bystander U937 cells were clearly relayed on the activated ERK and p38 pathways in the irradiated Beas-2B cells, and the upregulation of TNF-α and IL-8 mRNAs in co-cultured Beas-2B cells was also partly due to the activated NF-κB pathway in the...

Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - May 1, 2016 Category: Cytology Source Type: research