Sphingolipids make up a family of molecules associated with an array of biological functions, including cell death and migration. Sphingolipids are often altered in cancer, though how these alterations lead to tumor formation and progression is largely unknown. Here, we analyzed non–small-cell lung cancer (NSCLC) specimens and cell lines and determined that ceramide synthase 6 (CERS6) is markedly overexpressed compared with controls. Elevated CERS6 expression was due in part to reduction of microRNA-101 (miR-101) and was associated with increased invasion and poor prognosis. CERS6 knockdown in NSCLC cells altered the ceramide profile, resulting in decreased cell migration and invasion in vitro, and decreased the frequency of RAC1-positive lamellipodia formation while CERS6 overexpression promoted it. In murine models, CERS6 knockdown in transplanted NSCLC cells attenuated lung metastasis. Furthermore, combined treatment with
Motoshi Suzuki, Ke Cao, Seiichi Kato, Yuji Komizu, Naoki Mizutani, Kouji Tanaka, Chinatsu Arima, Mei Chee Tai, Kiyoshi Yanagisawa, Norie Togawa, Takahiro Shiraishi, Noriyasu Usami, Tetsuo Taniguchi, Takayuki Fukui, Kohei Yokoi, Keiko Wakahara, Yoshinori Hasegawa, Yukiko Mizutani, Yasuyuki Igarashi, Jin-ichi Inokuchi, Soichiro Iwaki, Satoshi Fujii, Akira Satou, Yoko Matsumoto, Ryuichi Ueoka, Keiko Tamiya-Koizumi, Takashi Murate, Mitsuhiro Nakamura, Mamoru Kyogashima, Takashi Takahashi
Lamellipodia formation/membrane ruffling requires C16:0 ceramide.