C2-ceramide exhibits antiproliferative activity and potently induces apoptosis in endometrial carcinoma

The purpose of the present study was to investigate the effects of an exogenously administered cell-permeable synthetic ceramide analogue, C2-ceramide (N-acetyl-sphingosine) on the growth, cell cycle, and death of Ishikawa human endometrial carcinoma cells. We investigated the effects of C2-ceramide on Ishikawa endometrial cancer cell lines in vitro. The cells were treated with C2-ceramide, and its effects on cell growth, cell cycle, apoptosis, and related measurements were investigated. MTT assays showed that C2-ceramide, a cell-permeable analogue of ceramide, significantly induced dose- and time-dependent death in human endometrial carcinoma Ishikawa cells. Cell-cycle analysis indicated that their exposure to C2-ceramide decreased the proportion of cells in S phase and increased the proportion in G0/G1 and/or G2/M phases of the cell cycle. Induction of apoptosis was confirmed by annexin V staining of externalized phosphatidylserine and loss of the transmembrane potential of mitochondria. This induction occurred in concert with the altered expression of genes related to cell growth, malignant phenotype, and apoptosis, including cleavage of poly-ADP ribose polymerase. Furthermore, we demonstrated that the amount of phosphorylated Akt was decreased by C2-ceramide. These results raise the possibility that C2-ceramide may prove particularly effective in the treatment of endometrial cancers.