Photodynamic therapy with verteporfin accelerates apoptotic bleb formation in human ameloblastoma

Objective: Although benign, ameloblastoma is a locally aggressive lesion in some patients and the development of additional treatments is needed. Verteporfin (VP) is a photosensitizer exhibiting considerable photocytotoxicity in various tumor cells. We aimed to investigate the effects of verteporfin photodynamic therapy (VP PDT) on ameloblastoma.Methods: Eighteen patients who underwent surgery for ameloblastoma were randomly selected. We performed an immunohistochemical assessment to investigate the expression of low-density lipoprotein receptor (LDLR) and Yes-associated protein (YAP), targets of VP, in human ameloblastoma tissues and cultured human ameloblastoma cell line (HAM1). The effect of VP PDT on cell proliferation and apoptosis in HAM1 was analyzed.Results: The expression of LDLR and YAP were detected in human ameloblastoma tissues and HAM1. LDLR expression was significantly higher in patients who had previously undergone surgery than in patients who were receiving it for the first time. The cytotoxic effect of the combination of low-concentration VP administration and laser irradiation was comparable to high-concentration VP administration with and without laser irradiation. The addition of laser irradiation to VP administration significantly accelerated apoptotic bleb formation compared with VP administration alone.Conclusion: VP PDT has the potential to become an additional treatment for large-sized ameloblastoma.