Effects On Anti-proliferation And Inducing Apoptosis And Gene Expressions Of Hydroxycamptothecin Combined With 5-Fu And γ-INF For MGC-803 Cell Of Gastric Cancer

Objective : To research the anti-proliferation and apoptosis inducing effects of hydroxycamptothecin(HCPT) on MGC-803 gastric cancer cell line combined with 5-FU and y-INF and the influences on genes expressions . Methods : 1. Using the MTT assay detected the suppressive effect of HCPT to MGC-803 gastric cancer line combined with 5-FU and y-INF 2. The morphological changes of the apoptosis cell waere observed by invert microscope ,MTT assay , electron microscope and acridine orange/ethidium bromide stain 3. The apoptosis inducing effect of the medicine on MGC-803 gastric cancer cell line was evaluated by TUNEL methods 4. The positive expression of Ki-67 Bcl-2 Bax were determined by immnocytochemistry (ICC). Result (1) MTT assay showed that 0.5-50μg/ml of HCPT ,2-25μg/ml 5-FU and 1000-15000u/ml y-IFN had the inhibitive action on MGC-803 gastric cancer cell line respectively and had a concentration dependence relationship. The inhibition rate was different significantly (P<0.05 or P<0.01) among the three kind of medicines with different concentration. The inhibition rate is different significantly(P<0.05 or P<0.01)among the combined group and also had a concentration dependence relationship, further more the combined group(HCPT12μg/ml+5-FU25μg/ml+gamma-INF1500u/ml)/3isdifferentsignificantly(P<0.05 or P<0.01)with each single medicine at triple concentration . (2)Morphologic changes of cell apoptosis that the microvillus disappeared,cytoplasm had vacuolation , chromation are pyknosis and coagulate to mass clustered around the membrane are revealed by electron microscope.(3)The AO/EB fluorescence stain showed that chromatin coagulated ,cytoplasm shrinked led to cell contract to bull shape when apoptosis occured (4)Tunlel showed that the single and combined treating group had a quantity depending effects of apoptosis inducing respectively and the action came to maximum at 48' hour and decreased as time prolonged. The combined medicine treating group A,B>C and D have significantly different(P<0.05 or P<0.01). effect of apoptosis inducing on MGC-803 gastric cancer cell line compared with single medicine treating group at triple concentration except few treating time and concentration(p>0.05) ; the group B,C and D had a consistent significant difference(P<0.05 or P<0.01)compared with single medicine treating group.(5)Ki-67 anti-proliferation test indicated that the single treating group as well as combined treating group had a quantity depending effects of apoptosis inducing on MGC-803 gastric cancer cell line respectively and the effect came to maximum at 48th hour and decreased as time prolonged. The combined medicine treating group A,B,C and D have significantly different (P<0.05 or PO.01) effect of apoptosis inducing on MGC-803 gastric cancer cell line compared with single medicine treating group at triple concentration except certain treating time and concentration(p>0.05) ; the group B,C and D had a consistent significant difference(P<0.01) comparedwith single medicine treating group. (6) The expression of oncogene Bcl-2 decreased and the expression of anti-oncogene Bax increased after the administration of HCPT at concentration of 12ug/ml.Conclusions: (1) HCPT ,5-FU and gamma- INF have effects of anti-proliferation and apoptosis inducing on MGC-803 gastric cancer cell line respectively (2) HCPT effects of anti-proliferation and apoptosis inducing on MGC-803 gastric cancer cell line was enhanced when combined with 5-FU and y-INF(3)Our study indicate that HCPT induce the apoptosis of MGC-803 gastric cancer cell line and the molecular biological mechanism is related to the suppressing the expression of oncogene Bcl-2 and inhance the expression of anti-oncogene Bax.