S100A2 and keratoconus: Keratin 6A (KRT6A) belongs to the keratin gene family and contributes to the activation of follicular keratinocytes following wounding in physiological conditions.6 Furthermore, previous studies indicated that KRT6A can activate the SRC pathway, and promote the development of intestinal villus.7 Calcium sensors and modulators, such as A2 (S100A2), are involved in calcium signaling within cells.8 S100A2 is also a composed protein of keratoconus corneal proteome, co-expressed with and regulated by KRT6A.9 Several cancer types have been found to have dysregulation of KRT6A or S100A2.