Reversal Effects Of Euphorbia Helioscopia L. Ethyl Acetate Extract On Multidrug Resistant Of Cell SGC7901/DDP

Objectives:To study whether Euphorbia helioscopia L ethyl acetate extract (EAE) have the reversal effect on gastric cancer resistant cells SGC7901/DDP as well as explore it’s possible mechanisms, and make a preparation for the further study.Methods:We choose ethyl acetate extract from Euphorbia helioscopia L by the system solvent as reagents used in this study. The cells were SGC7901, SGC7901/DDP, SGC7901/DDP+EAE(final concentration lOug/mL), and SGC7901/DDP+EAE(final concentration 20ug/mL). First part, the present study mainly observed cell morphology and growth conditions, draw growth curve of SGC7901 and SGC7901/DDP cells, and then observe two cell lines’invasion and metastasis ability. Drug resistance observed by MTT and RT-PCR that study the expression of MDR 1 and LRP mRNA. In second part, the reversal effects of EAE were studied. Drug resistant cell line SGC7901/DDP were observed by MTT, MDR 1 and LRP mRNA detected by RT-PCR and P-gP and LRP are quantitated by western blot.Results:Compared with SGC7901 cells, SGC79041/DDP cell has some visible changes: irregular, fuzzy boundaries, cell population doubling extend approximately 6.5h respectively are 32 ± 0.82h, and 25±0.76h, invasion and metastasis ability of cells increases, SGC-7901/DDP to 5-FU and cisplatin showed resistance, and resistance to cisplatin is more obvious; The expression of MDR 1 and LRP mRNA in SGC7901/DDP cells is significantly higher than SGC7901 cells and statistically significant. MTT assay detects the reversal effect of EAE found in EAE final concentration of 10ug/mL and 20ug/mL when multiple drug 5-FU was 3.80,2.68, reverse index: 2.28,2.93; multiple drug resistance was 4.40 DDP,4.58, reverse index:3.24,4.58. RT-PCR was used to detect MDR 1 and LRP mRNA expression in cells.We found that the mRNA expression of MDR 1 and LRP were the highest in SGC7901/DDP cells,which were decreased in SGC7901/ DDP+EAE (final concentration of lOug/mL) and SGC7901/DDP+EAE (final concentration of 20ug/mL).The mRNA expression of MDR1 and LRP decreased more significantly in SGC7901/ DDP+EAE (final concentration of 20ug/mL) at the same time. Western blot detection of protein P-gp and LRP protein, found in SGC7901 cells detected only low levels of expression of P-gP detected a very low amount of protein LRP, but in SGC7901/DDP cells, P-gP protein and LRP highest protein expression in SGC7901/DDP+EAE (final concentration of lOug/mL) of P-gP protein expression and protein LRP decline in SGC7901 DDP EAE (final concentration of 20ug/mL) of the protein expression of P-gP and LRP decline more apparent.Conclusions:1. EAE can reverse MDR in SGC7901/DDP cell line; 2. Down regulation of MDRl and LRP gene and its corresponding proteins P-gP and LRP expression decrease may be underlying mechanism of EAE reversal gastric cancer cells SGC7901/DDP resistant.