IL6 and rheumatoid arthritis: The fine tuning of IL-6 expression is crucial since dysregulation of IL-6 has been attributed to many diseases such as atherosclerosis [21], systemic lupus erythematosus [22], Behçet′s disease [23], diabetes [24], multiple myeloma [25], depression [26], Alzheimer′s Disease [27], prostate cancer [28] and rheumatoid arthritis [29].