Chronic inflammation reduces the anti-cancer defenses of the cells
There is a strong correlation between chronic inflammation, such as ulcerative colitis, and the increased risk of cancer onset. This finding has been reported in a study realized by Bologna University and S. Orsola-Malpighi Hospital, published in the international scientific journal Oncogene. The research has demonstrated this correlation not only in vitro, but also "in vivo" in hospitalized patients.
The study is the result of collaboration between a team of researchers coordinated by Massimo Derenzini (Laboratory of Clinical Pathology, Department of Experimental, Diagnostic and Specialty Medicine) and the team coordinated by Carlo Calabrese (Inflammatory Bowel Disease Research Unit, Department of Medical and Surgical Sciences), and has been made possible thanks to a grant from the Italian Association for Cancer Research (AIRC).
As explained by the researcher Elisa Brighenti, first author of the published work, "when a chronic inflammatory process is developing in the human body, a substance called interleukin-6 (IL-6) is released into the tissues. In this study we have shown that IL-6 is responsible for a reduction of the anti-cancer defenses of the cells, causing the acquisition of changes characteristic of neoplastic cells. This is due to the activation of a mechanism that leads to a reduction of p53 expression and activity. p53 is the main "cellular guardian of genome integrity" and has the function to protect the cell from the accumulation of genetic mutations that may promote tumor formation. Furthermore, we have shown that chronic exposure to IL-6 confers to cells the ability to migrate and to invade the surrounding tissues. "
The research has clarified the mechanism of action of interleukin-6 not only in vitro, using cell cultures, but also "in vivo" in patients with ulcerative colitis, a chronic inflammation of the colon characterized by a high release of IL-6 and associated with an increased risk of cancer. The clinical trials performed on these patients also showed that the effects of interleukin-6 described above can be blocked by the treatment with anti-inflammatory drugs.
"This work – as reported by Elisa Brighenti - sheds light on one possible mechanism linking chronic inflammation and cancer, and identifies interleukin-6 as a potential factor favoring the onset of malignant disease. These results could explain the increased frequency of cancer, not only in subjects with chronic inflammatory diseases, but also in obese and type 2 diabetes patients, two conditions which are characterized by an increased release of interleukin-6.