(Decock et al., 2008; Decock et al., 2011; Korpi et al., 2008) For instance, in breast cancer, elevated plasma levels of MMP‐8 seem to have a protective effect against lymph node metastasis, (Åström et al., 2017) and squamous cell carcinoma of the tongue, in which high‐tumor MMP‐8 expression had associations with improved cancer‐specific survival. This evidence concerns the gene MMP8 and tongue squamous cell carcinoma.