The expression of TRPV1 was also increased in the epidermal KCs of patients with Herpes Zoster, SFN, diabetic peripheral neuropathy (DPN), and nerve injury; with the expression level correlated with pain intensity (Facer et al., 2007; Wilder-Smith et al., 2007; Han et al., 2016). The gene discussed is TRPV1; the disease is dry eye syndrome.