Qin et al. used western blot analysis, real-time PCR, semi-quantitative RT-PCR analyses, and IHC in order to compare the levels of periostin in normal oral epithelial cells, cancer-associated fibroblasts (CAFs) and normal fibroblasts (NFs) isolated from head and neck cancer (HNC) tissues, as well as cell lysates from 6 HNC cell lines [61]. The gene discussed is POSTN; the disease is cancer.