著者
Izumi Tsukayama Keisuke Toda Yasunori Takeda Takuto Mega Mitsuki Tanaka Yuki Kawakami Yoshitaka Takahashi Masumi Kimoto Kei Yamamoto Yoshimi Miki Makoto Murakami Toshiko Suzuki-Yamamoto
出版者
SOCIETY FOR FREE RADICAL RESEARCH JAPAN
雑誌
Journal of Clinical Biochemistry and Nutrition (ISSN:09120009)
巻号頁・発行日
vol.62, no.2, pp.139-147, 2018 (Released:2018-03-01)
参考文献数
41
被引用文献数
7

Hyperproduced prostaglandin E2 by cyclooxygenase-2 and microsomal prostaglandin E synthase-1 evokes several pathophysiological responses such as inflammation and carcinogenesis. Our recent study demonstrated that Dioscorea japonica extract suppressed the expression of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 and induced apoptosis in lung carcinoma A549 cells. In the present study, we investigated the effects of Dioscorea japonica on squamous cell carcinoma of mouse skin. Dioscorea japonica feeding and Dioscorea japonica extract topical application suppressed the expression of cyclooxygenase-2, microsomal prostaglandin E synthase-1, interleukin-1β and interleukin-6 and inhibited tumor formation, hyperplasia and inflammatory cell infiltration. Immunohistochemical analyses showed the immunoreactivities of cyclooxygenase-2 and microsomal prostaglandin E synthase-1 in tumor keratinocytes and stronger immunoreactivities of cyclooxygenase-2 and hematopoietic prostaglandin D synthase in epidermal dendritic cells (Langerhans cells). Treatment with Dioscorea japonica decreased the immunoreactivity of cyclooxygenase-2 and microsomal prostaglandin E synthase-1. These results indicate that Dioscorea japonica may have inhibitory effects on inflammation and carcinogenesis via suppression of the prostaglandin E2 synthetic pathway.