Abstract

Purpose：Retinoids derived from vitamin A have diverse effects on development, morphogenesis, and homeostasis. They also have effects for prevention and treatment of cancers. In this study, the effect of N-(4-hydroxyphenyl) retinamide (4-HPR) on growth and/or proliferation of human gastric adenocarcinoma cell line SNU1 was investigated. Materials and Methods：The cytotoxic effect of 4-HPR was assessed by MTT assay. The apoptosis induced by 4-HPR was analyzed with cytoplasmic DNA Fragmentation, flow cytometry, and Western blot.
Results
：4-HPR induced cell death of SNU1. The cytoplasmic DNA fragmentation was increased time dependently after treatment of 4-HPR and the cells in the sub-G₀/G₁ fraction of flow cytometric analysis were also increased time dependently after treatment of 4-HPR. The cleavage of caspase 3 and PARP were detected after treatment of 4-HPR to SNU1. The phosphorylations of Raf, ERK and AKT were induced by 4-HPR but after pre-treatment of MAPK inhibitor (PD98059) or PI-3 kinase inhibitor (LY294002) the 4-HPR-induced cytoplasmic DNA fragmentation, the cells in the sub-G0/G1 fraction fraction of flow cytometric analysis, and cleavage of caspase 3 and PARP were diminished in SNU1 cells.
Conclusion
：The results show that 4-HPR induces apoptosis of SNU1 and this 4-HPRinduced apoptosis may be mediated through ERK1/2 and PI3 kinase signaling pathways in SNU1.

• Keywords: 4-HPR, SNU1, apoptosis;