CXCL12 and neoplasm: ROS also initiated the inflammatory reaction by the NF-κB pathway to secrete chemokines both in tumor cells and the tumor microenvironment, such as CCL2, CCL3, CXCL2, and CXCl12, which were upregulated by Se-PC PDT, and CCL24 and CXC17, which were downregulated by Se-PC PDT in the tumor niche.