Study On The Anti-tumor Mechanism Of Ginsenoside Rg3: Suppression LeY Synthesis And EGFR Activity In MCF-7 Cells

Objective: To analyze the expression of PCNA, FUT1/FUT4, LeY, EGFR, p-EGFR, and their correlations in breast cancer cells (MCF-7) when they were treated with ginsenoside Rg3(Rg3).Methods: MTT,RT-PCR,Western blot,FCM,indirect immunofluoresce- nce were used to analyze the alterations of cells proliferation, and the level of PCNA, FUT1/FUT4, LeY, EGFR, p-EGFR expression in MCF-7 cells after Rg3.treatment.Results: 1.Rg3 obviously suppressed the proliferation of tumor cells (>80μg/ml). There were no statistical difference between 24h and 48h when the cells incubated with Rg3. 2.When the concentration of Rg3 was at 160μg/ml (IC50), it could effectively inhibited the expression of the molecules mentioned above, but the expression of EGFR was unchanged. 3. Incubation of the cells with anti-LeY antibody (BG8) could suppress p-EGFR but not EGFR. 4. Anti-LeY antibody decreased LeY on EGFR.In conclusion,we can suppose that Rg3 can inhibit the proliferation of breast cancer cells by downregulating the expression of the FUT1/FUT4 which decreases the synthesis of LeY on EGFR.The expression of LeY on EGFR plays a important role for EGFR to bind with its ligands.Suppression of the expression of LeY on EGFR will inactivate EGFR and the downs- tream signal pathway.This study provides a new information to explore the EGFR related signal transduction pathway and the regulation of LeY on EGFR as a target by Rg3.