Their research revealed that overexpression of microRNA-139 (miR-139), observed in the hippocampus of AD mice, impaired spatial memory, object recognition, fear response, and reactions to pro-inflammatory stimuli by inhibition of intercellular adhesion molecule 1 (ICAM-1) and cluster of differentiation 40 (CD40), and reduction in interleukin-6 (IL-6) and tumor necrosis factor-a (TNF-a). Here, IL6 is linked to Alzheimer disease.