Role of interleukin-23 circulating levels increase in resected colorectal cancer before and after chemotherapy: preliminary data and future perspectives.

Expression of IL-23, a heterodimeric cytokine involved in the induction of Th17 cells, is increased in human tumors. Although the endogenous IL-23 expression has been reported to promote tumor development and growth, the studies using local and systemic administration of IL-23 have shown that its application at the excessive amount induces antitumor immune responses. IL-23 is, today, considered the key driver of intestinal inflammation and its role in inflammatory responses is tissue-specific. The aim of this study was to investigate the role of circulating levels of IL-23 in patients with resected colorectal cancer (CRC) before and after chemotherapy, respect to healthy controls. Twenty-five patients were enrolled between June 2007 and January 2009, and followed through 2010. All patients underwent chemotherapy, mostly FOLFOX4. Twenty-sex and age-matched healthy donors were recruited as controls. IL-23 serum concentrations, measured by a quantitative enzyme immunoassay technique, were significantly higher in patients with resected CRC (26.02 ± 28.63 pg/ml versus 7.1 ± 6.4 pg/ml, P < 0.001) and after chemotherapy respect to controls (21.74 ± 23.82 pg/ml versus 7.17 ± 6.43 pg/ml, P < 0.001). An increase was documented also before chemotherapy (26.02 ± 28.63 pg/ml versus 21.74 ± 23.82 pg/ml, P = 0.7) but not statistically significant. This work investigated, for the first time, the role of IL-23 in CRC resection and chemotherapy, showing no correlation with the severity of disease, tumor removal, and chemotherapeutic treatment. However, other works are needed to better clarify if IL-23 could be considered a key-molecule in human CRC and a target for tumor treatment.