Background & objective: Cellular FLICE inhibitory protein (cFLIP) plays an important role in cell apoptosis, researches of antisense oligonucleotides (ASODN) of cFLIP gene may provide a new method or protocol for treatment of human gastric cancer. This study was to explore effect of cFLIP ASODN on apoptosis of human gastric cancer cell line BGC823.
Methods: Human cervical cancer cell line HeLa was used as control, cFLIP ASODN was introduced into BGC823 cells and HeLa cells, reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot were used to detect cFLIP(L/S) (cellular FLIP(Short) and cellular FLIP(long)) mRNA and protein. The 5'FAM-conjugated ASODN was created complementary to a sequence that included the start site of FLIP open reading frame. After introducing, MTT was used to detect cell inhibition rate,TUNEL and flow cytometry (FCM) were used to detect cell apoptosis, and Western blot was used to detect protein level of cFLIP.
Results: The encoding mRNA and protein of cFLIP(L) and cFLIP(S) can be detected in both HeLa and BGC823 cells. MTT revealed that cFLIP ASODN significantly inhibited proliferation of BGC823 cells (P< 0.05) in a concentration-dependent manner. TUNEL staining detected positive FLIP expression, specific apoptotic peak can be detected before G1 peak by FCM, and Western blot revealed that protein level of cFLIP(L) and cFLIP(S) decreased significantly (P< 0.05).
Conclusion: The cFLIP(L/S) mRNA and encoded proteins expressed in both HeLa and BGC823 cells. ASODN may down-regulate cFLIP(L/S) protein level, and initiate apoptosis of BGC823 cells.