“…Previous studies have suggested that several miRNAs were abnormal expression in the progress of periodontal disease and regulated multifarious genes such as RUNX2, osteocalcin (OC), and EGFR (Motedayyen, Ghotloo, Saffari, Sattari, & Amid, ; Xie et al, ; Zhou et al, ). MiR‐218, a tumour suppressor, is significantly downregulated in various cancers (Deng et al, ; Shi et al, ) and inflammatory disorders (Xu et al, ). For example, the decrease of serum miR‐218 levels was observed in the inflammation induced by cigarette smoking, and miR‐218 overexpression would repress TNFR1‐mediated activation of NF‐κB and resulted in decreasing levels of serum IL‐6 and IL‐8 (Xu et al, ).…”