CXCL12 and oral cavity squamous cell carcinoma: Although CXCL12 promotes the expression of Snail1 (Liao et al., 2016; Lv et al., 2015) and Twist1 (Yao et al., 2016) in glioblastoma cancer cells, and of Snail1 in human oral squamous cell carcinomas (Taki et al., 2008), no reports show CXCL12‐induced expression of Snail1 or Twist1 in tumour cells of gastric cancers.