Objective To investigate the changes in function of liver and kidney of the rabbits bearing VX2 liver tumor after transarterial embolization and hyperthermia with magnetic nanoparticles suspended in lipiodol(MN-L) and its therapeutic effect Methods Thirty-two rabbits bearing VX2 liver tumor were randomly divided into four groups and each group contained 8 rabbits The four groups were MN-L embolization hyperthermia group (Group A), MN-L embolization group(Group B),Lipiodol embolization group(Group C), and Control group (Group D), Each rabbit in Group A and B was embolized with 0.5-0.8 ml MN-L through hepatic artery, while each rabbit in Group C was embolized with 0.5-0.8 ml lipiodol.Hyperthermia in alternating magnetic field was performed in Group A after embolization.The remaining groups did not undergo hyperthermia.The rabbits in control group were not treated.The function of liver and kidney of all the animals was measured 1d before embolization,and 1,7,and 14 d after embolization/hyperthermia respectively.Alanine aminotransferase (ALT) and aspartate aminotransaminase (AST) were used to reflect the function of liver,and blood urea nitrogen(BUN) and creatinine (Cr) were used to reflect the function of kidney.CT was performed on all of subjects before and after embolization to determine the embolization effect and the tumor size, and follow-up CT was performed weekly.All of subjects were sacrificed 14 days after embolization/hyperthermia, and their livers, spleens, kidneys and lungs were removed for histopathology examination.The data from every group were analyzed using analysis of variance of repeated measure data.Results On 1 day before embolization and 1,7, and 14 d after embolization/hyperthermia, the function of liver of the rabbits was as follows:Group A:ALT was (43.9±19.0),(795.1±327.1),(67.0±9.3), and(41.9±10.8) U/L respectively,and AST was (50.2±13.6),(1011.2±655.9),(62.4±24.1),and(51.6±7.9) U/L respectively; Group B: ALT was(45.0±19.1),(580.8±160.4),(67.2±31.0),and(47.6±7.8) U/L respectively, and AST was (52.9±20.3),(735.2±186.1),(57.9±24.8),and (50.9±9.8) U/L respectively; Group C: ALT was (47.4±14.6),(558.5±167.8),(63.5±21.9),and (48.0±9.3) U/L respectively, and AST was (51.8±9.5),(752.5±112.0),(56.5±20.6),and(51.4±8.6) U/L respectively.Both ALT and AST mean values of the rabbits were significantly elevated 1 d after embolization/hyperthermia in Group A, B and C, and the data showed statistically significant difference comparing with that before therapy and that of Group D 1 d after therapy (P<0.01).The function of liver showed no statistically significant difference between 7 or 14 days after embolization and 1 day before embolization in Group A,B and C. BUN and Cr mean values in pre-embolization and post-embolization rabbits revealed no statistically significant difference in group A, B, C and D.The MN-L /lipiodol were deposited in the tumor when it was injected, which was validated by CT.To compare with immediate CT after embolization, the MN-L deposited in tumors was not significantly different on CT 7 d after embolization .On the 14 th day after treatment,the MN-L deposited in tumors became concentrative and compact in Group A, while the MN-L/lipiodol deposited at the rim of tumors disappeared on CT in five rabbits of Group B and C.And the tumor size decreased by 21.7% compared to that before treatment in Group A [from (7.8±1.4)cm~3 to(6.1±0.6) cm~3,F=17.56, P<0.01], but tumor size increased by 16.2% and 18.9% in Group B and C respectively [from (7.9±1.1)and (7.8±0.9)cm~3 to (9.1±0.8) and (9.3±1.0)cm~3, F =25.23,55.50, P<0.01].Histopathologically, the tumor of Group A was necrotic for at least 80% 14 day after embolization, while the tumor of Group B and C was necrotic for 30% to 50% .Conclusion Transarterial embolization and hyperthermia with MN-L is safe, effective and feasible on the rabbits bearing VX2 liver tumor. Key words: Liver neoplasms, experimental; Nanoparticles; Chemoembolization, therapeutic; Models, animal
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