Hcpt And To Nctd Killing Effect Of The Difference Between Tumor And Host Cells

Camptothecin(CPT)is an alkaloid extracted from Camptotheca acuninata Decne,the only selective inhibitor of DNA topoisomeraseⅠ(TopoⅠ). Hydroxyamptothecin(HCPT)is another alkaloid that has effective anti-cancer activity, and was extracted from Camptotheca acuninata after CPT.Compared with CPT, HCPT has stronger anti-cancer effect and lower toxicity,and be widely used in clinical,mainly used in the treatment of cancer,such as non small cell lung cancer, liver cancer,bladder cancer and so on.Cantharidin is the effective ingredient of Chinese medicine Mylabris.Norcantharidin(NCTD)is the demethylated analogue of cantharidin,and has significant anti-cancer activity and small side effects,and be used widely in the treatment of cancer,such as liver cancer,lung cancer and so on.Most of the anti-caner drugs can kill normal host cell when they reacted,and even kill more normal host cell than tumor cell.So,it is very necessary and urgent to study the different effect about anti-cancer drug between tumor and its normal host cell.This study choose lung cancer cell(A549)and its normal host cell embryo lung fibroblasts(MRC-5),these two cell lines are come from the same human tissue.In order to research the distinctions between the role of anti-A549 and MRC-5 of HCPT and NCTD,this study use different concentrations of HCPT and NCTD to affect these two cell lines.The result shows that:HCPT induced significant proliferation inhibition in A549 and MRC-5 cells when the concentration upon 50um/L.In 0-72 hours,MRC-5 cell was more resistant to HCPT induce cytotoxicity in the concentration range of 50-100μm/L.The IC50 of 24h HCPT treatment for A549 and MRC-5 were 155.97 and＞200μmol/L,48h were A54μ9＜50μmol/L and MRC-5 133.96μmol/L,72h were A549＜50μmol/L and MRC-550μmol/L;NCTD induced proliferation inhibition in A549 and MRC-5 cells when the concentration upon 30μm/L,and MRC-5 cells were more resistant to NCTD induce cytotoxicity in the concentration range of 30-60μm/L and the time range of 0-24h.The IC50 of 24h NCTD treatment for A549 and MRC-5 were 97.71 and＞120μmol/L,48h were A549 79.66μmol/L and MRC-5 68.05μol/L,72h were A549 50.04μol/L and MRC-5 36.98μol/L.A549 and MRC-5 were exposed to HCPT and NCTD for a period of time(24h), and then cultured 5 days with normal culture medium.The result shows that:HCPT also inhibited subsequent cell proliferation in both two cells within 5 day,but the different cytotoxic effects of HCPT that A549 was stronger than MRC-5 is not significantly;NCTD inhibited subsequent cell proliferation in both A549 and MRC-5, but the different cytotoxic effects of NCTD that A549 was stronger than MRC-5 is also exist in the 3-4 day of the concentration of 30μmol/L.Flow cytometry analysis indicates 50μmol/L HCPT delays cell cycle progression of A549 and MRC-5 with apparent effect on S phase,and a marked increase in apoptosis after 48h of A549 only;30μmol/L NCTD delays cell cycle progression of A549 with apparent effect on G2-M phase,and weakly effect of MRC-5.The apoptosis of MRC-5 was slightly higher after 48h.In order to study anti-cancer drug sensitivity in-vivo environment,this study established a tumor and host cells co-culture system in vitro specially,researched the growth characteristics of A549 and MRC-5 and the sensitivities of these tow cell line about HCPT and NCTD.The result shows that there are no difference in drug sensitivities of HCPT and NCTD between A549 cultured alone and be co-cultured with MRC-5;However,MRC-5 cell was more sensitive with HCPT when be co-cultured with A549 in 12h and 72h,and also more sensitive with NCTD when be co-cultured with A549 in 12h and 24h.