Affiliations: [a] Department of Dermatology, Third Affiliated Hospital of Inner Mongolia Medical University, Baotou 014010, Inner Mongolia, China | [b] Inner Mongolia Medical University, Hohehot 010000, Inner Mongolia, China | [c] Hunan Youcheng Biotechnology Co. Ltd, Changsha 410000, Hunan, China
Abstract: AIMS AND BACKGROUND: Squamous cell carcinoma (SCC) is one of the most common skin cancers. Photodynamic therapy (PDT) is a non-invasive treatment for SCC, but it is usually effective only on tumors just under the skin. Resveratrol (Res) is a polyphenolic compound, which is capable of promoting apoptosis of a variety of cancer cells. Res administration is non-invasive and effective on SCC, thus it may be used as an adjuvant for PDT. So far, there is no published study investigating the combination use of PDT with Res to improve clinical outcome of SCC. So in this study, we will examine the effectiveness of combined treatment of PDT and Res as well as its underlying mechanism. METHODS: The human HaCaT keratinocytes and human A431 epidermoid carcinoma cells were treated with ALA-PDT or/and Res, and cell proliferation and apoptosis were evaluated by MTT and flow cytometry respectively afterwards. p-ERK, p38, p53 and caspase-3 protein expression was examined by western blot. Then a p38 inhibitor was added to test the involvement of p38 pathway in A431 cells responding to ALA-PDT and Res treatments. RESULTS: The results showed that Res could enhance the effect of ALA-PDT on cell proliferation and apoptosis in A431 cells. We also found that the expression of p-ERK, p-p38, p53 and caspase-3 was increased. However, inhibition of p38 pathway attenuated the effect of Res. CONCLUSION: Our study demonstrated that Res could enhance the effect of ALA-PDT against skin cancer cells through p38/ MAPK pathway.
