Cornulin (CRNN) Contributes to the Development of Cutaneous squamous cell carcinoma via Activation of AKT in SCL-1

Cutaneous squamous cell carcinoma (cSCC) is one of the common malignant skin tumors with increasing incidence in recent years, especially in the elderly. There is growing evidence that cornulin (CRNN), as an oncogene, participates in the pathogenesis of various tumors, but its role in cSCC is still unclear. Here, we found that the expression of CRNN was significantly upregulated in cSCC samples compared with normal skin. Downregulation of CRNN expression in cSCC cell line SCL-1 induced growth arrest during the G1/S transition, inhibited cell proliferation, promoted cell apoptosis, and decreased cell invasion and migration. In contrast, overexpression of CRNN promoted cell proliferation and protected cells from basal apoptosis, and these oncogenic effects of CRNN were associated with activation of AKT. Using a mouse xenograft model, we demonstrated that depletion of CRNN suppressed in vivo cSCC tumor growth. These results suggest that CRNN is involved in the occurrence and development of cSCC. Our study provides a the foothold for further evaluating the therapeutic efficacy of CRNN on cSCC.