Potential mechanisms of tumor progression associated with postoperative infectious complications

AbstractThere is increasing evidence that postoperative infectious complications (PICs) are associated with poor prognosis after potentially curative surgery. However, the role that PICs play in tumor development remains unclear. In this article, we reviewed the literature for novel insights on the mechanisms of cancer progression associated with PICs. The Medline and EMBASE databases were searched for publications regarding the role of suppression of antitumor immunity by PIC in tumor progression and selected 916 manuscripts were selected for this review. In addition, a summary of the authors ’ own experimental data from this field was set in the context of current knowledge regarding cancer progression under septic conditions. Initially, sepsis/microbial infection dramatically activates the systemic immune system with increases in pro-inflammatory mediators, which results in the devel opment of systemic inflammatory response syndrome; however, when sepsis persists in septic patients, a shift toward an anti-inflammatory immunosuppressive state, characterized by macrophage deactivation, reduced antigen presentation, T cell anergy, and a shift in the T helper cell pattern to a predo minantly TH2-type response, occurs. Thus, various cytokine reactions and the immune status dynamically change during microbial infection, including PIC. We proposed three possible mechanisms for the tumor progression associated with PIC: first, a mechanism in which microbes and/or microbial PAMPs...
Source: Cancer and Metastasis Reviews - Category: Cancer & Oncology Source Type: research