Macrophage migration inhibitory factor as an indicator of chronic inflammation and metabolic risk in women

Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine with multiple functions in the immune system and other tissues. Physiologically, MIF has been implicated in the regulation of the immune response, in pathogen clearance, in cell regeneration, in the regulation of insulin secretion, and in the regulation of cardio- and neuro-protective effects. Pathologically, high MIF levels have been associated with inflammatory and autoimmune diseases, diabetes mellitus, obesity and cancer. The present study assessed serum MIF levels in women by ELISA. Subsequently, the possible relationship between MIF serum levels and risk factors associated with the development of breast and other types of cancer was evaluated. MIF serum levels in the studied population ranged between 80.7 and 4,790.5 pg/ml. Notably, high MIF serum levels were related to obesity (median 1,604.0 pg/ml; P=0.0197 vs. overweight and P=0.0002 vs. normal body mass index), a high waist-to-hip ratio (WHR; median 1,542.0 pg/ml; P=0.0126 vs. moderate WHR) and hypertension (median 1,582.0 pg/ml; P=0.0234). Also, a weak correlation was observed between MIF levels and aging (P=0.0239, r=0.1558). Furthermore, MIF levels were decreased in women with Breast Imaging Reporting and Data System (BI-RADS) classification 2 (P=0.0189) and 3 (P=0.0023) when compared with the levels in women with BI-RADS classification 1, and no other association was identified with the other cancer risk factors evaluated. In conclusion, the present results indicated that, although increased levels of MIF were not associated with increased breast cancer risk as evaluated by BI-RADS classification or other cancer risk factors, elevated MIF levels were related to states of chronic inflammation such as obesity, a high WHR and aging, indicating that an increase in the serum concentration of MIF may be related to metabolic disease.