AIM To investigate the effects of taxol onSMMC-7721 human hepatoma and itsmechanisms.METHODS In vitro cell growth was assessedby trypan blue exclusion method.Experimentalhepatoma model was established by seedingSMMC-7721 cells subcutaneously into Balb/c(nu/nu)nude mice.In vivo tumor growth wasdetermined by measurement of tumor diameterwith Vernier calipers.The syntheses of DNA,RNA and protein were analyzed by incorporationof ~3H-thymidine,~3H-uridine and ~3H-leucinerespectively.Using light and electronmicroscopes to observe the morphologicalchanges of cells including mitosis andapoptosis.RESULTS Taxol was effective against SMMC-7721 human hepatoma cell growth in the rangesof 2.5 nmol/L-10 nmol/L with mitotic arrestand apoptosis in vitro.DNA,RNA and proteinsyntheses in cells were also obviouslysuppressed by in vitro treatment of taxol for72 h.Taxol at 2.5 nmol/L reduced ~3H-thymidineuptake to about 34% of the control value(P<0.05).Increasing the dose of taxol to20 nmol/L resulted in a greater decrease in ~3H-thymidine incorporation to 60% of the controlvalue(P<0.01).At a concentration of 20 nmol/L,the ~3H-uridine and ~3H-leucine uptakeswere reduced to 52%(P<0.05)and 63%(P<0.01),respectively.In vivo,taxolsignificantly inhibited SMMC-7721 tumor growthat 10 mg/kg,i.p.,once daily for 10 d.A morethan 90% decrease in tumor volume wasobserved by day 11(P<0.01)similarly withmitotic arrest and cell apoptosis.CONCLUSION Taxol has a marked anticanceractivity in SMMC-7721 human hepatoma both invitro and in nude mice.Its mechanisms might beassociated with mitotic arrest,subsequently,apoptosis of the hepatoma cells.No obvioustoxicity was observed with in vivoadministration of taxoi. AIM To investigate the effects of taxol on SMMC-7721 human hepatoma and its mechanisms. METHODS In vitro cell growth was assessed by trypan blue exclusion method. Experimental pattern was established by seeding SMMC-7721 cells subcutaneously into Balb / c (nu / nu) nude mice. vivo tumor growth was determined by measurement of tumor diameter with Vernier calipers. The syntheses of DNA, RNA and protein were analyzed by incorporation of ~ 3H-thymidine, ~ 3H-uridine and ~ 3H-leucinerespectively. Using Light and electron microscopes to observe the morphological changes of cells including mitosis andapoptosis.RESULTS Taxol was effective against SMMC-7721 human hepatoma cell growth in the ranges of 2.5 nmol / L-10 nmol / L with mitotic arrest and apoptosis in vitro. DNA, RNA and protein syntheses in cells were also demonstrated by in vitro treatment of taxol for 72 h.Taxol at 2.5 nmol / L reduced ~ 3H-thymidine uptake to about 34% of the control value (P <0.05) .crecreasing the dose of taxol to 20 nmol / L resulted in ag A decrease of ~ 3H-thymidine incorporation to 60% of the control value (P <0.01) .At a concentration of 20 nmol / L, the ~ 3H-uridine and ~ 3H-leucine uptakeswere reduced to 52% 63% (P <0.01), respectively.In vivo, taxanesignificantly inhibited SMMC-7721 tumor growth 10 mg / kg, ip, once daily for 10 dA morethan 90% decrease in tumor volume wasobserved by day 11 (P <0.01) similarly withmitotic arrest and cell apoptosis. CONCLUSION Taxol has a marked anticanceractivity in SMMC-7721 human hepatoma both invitro and in nude mice. Later, apoptosis of the hepatoma cells. No obvioustoxicity was observed with in vivo administration of taxoi.