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Objective To investigate the killing effect of polymethylmethacrylate (PMMA) on spinal metastasis of transplanted VX2 carcinoma in experimental rabbit models. Methods Spinal metastasis of transplanted VX2 carcinoma model was successfully established in 18 rabbits. The experimental rabbits were randomly and equally divided into three groups with 6 rabbits in each group. Under CT guidance , PMMA or saline was injected into the center of VX2 tumor; in group A 0.3 ml of PMMA was used, in group B 0.1 ml of PMMA was used and in group C (control group) 0.3 ml saline was used. Twenty-four hours after the injection, the animals were sacrificed. Four tissue samples were obtained from the sites at 1 mm , 5 mm, 10 mm and 15 mm away from the PMMA mass in each rabbit of group A and group B , while four tissue samples were collected from different four sites from the tumor ’s center to border in each rabbit of group C. TdT-mediated dUTP nick-end labeling (TUNEL) method was used to determine the tumor cell apoptosis rate. Results After successful establishment of rabbit model, injection of PMMA was performed in sixteen among the eighteen rabbits. Technical success rates were 83.3% in both group A and B, and the success rate was 100% in group C. The difference in technical success rate was not significant. The mean tumor cell apoptosis rates of spinal VX2 carcinoma at 1 mm, 5 mm and 10 mm away from the PMMA mass in group A were (65.75±18.81)%, (50.00±14.24)% and(14.95±8.98)% respectively. The mean apoptosis rate in the control group was (9.79 ±5.24)%; the differences between the group A and the control group were statistically significant (P<0.05). The mean tumor cell apoptosis rate of spinal VX2 carcinoma at 15 mm away from the PMMA mass in group A was (10.30 ±8.13)%, which was not significantly different with that of the control group. The mean tumor cell apoptosis rates of spinal VX2 carcinoma at 1 mm and 5 mm away from the PMMA mass in group B were (49.20±15.57)% and(17.75±9.28)% respectively, which was significantly different with that of the control group(P<0.05); the mean tumor cell apoptosis rates at 10 mm and 15 mm away from the PMMA mass in group B were not significantly different with those of the control group. Statistically significant differences in the mean tumor cell apoptosis rates determined at 1 mm, 5 mm and 10 mm away from the PMMA mass existed between group A and group B(P<0.001). Conclusion PMMA can promote the apoptosis of tumor cells, properly increasing the injected amount of PMMA can enlarge the extent of tumor cell apoptosis.
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OBJECTIVE: The purpose of this study was to compare the antitumor effect and hepatotoxicity of an intraarterial delivery of low-dose and high-dose 3-bromopyruvate (3-BrPA) and those of a conventional Lipiodol-doxorubicin emulsion in a rabbit VX2 hepatoma model. MATERIALS AND METHODS: This experiment was approved by the animal care committee at our institution. VX2 carcinoma was implanted in the livers of 36 rabbits. Transcatheter intraarterial administration was performed using low dose 3-BrPA (25 mL in a 1 mM concentration, n = 10), high dose 3-BrPA (25 mL in a 5 mM concentration, n = 10) and Lipiodol-doxorubicin emulsion (1.6 mg doxorubicin/ 0.4 mL Lipiodol, n = 10), and six rabbits were treated with normal saline alone as a control group. One week later, the proportion of tumor necrosis was calculated based on histopathologic examination. The hepatotoxicity was evaluated by biochemical analysis. The differences between these groups were statistically assessed with using Mann-Whitney U tests and Kruskal-Wallis tests. RESULTS: The tumor necrosis rate was significantly higher in the high dose group (93% +/- 7.6 [mean +/- SD]) than that in the control group (48% +/- 21.7) (p = 0.0002), but the tumor necrosis rate was not significantly higher in the low dose group (62% +/- 20.0) (p = 0.2780). However, the tumor necrosis rate of the high dose group was significantly lower than that of the Lipiodol-doxorubicin treatment group (99% +/- 2.7) (p = 0.0015). The hepatotoxicity observed in the 3-BrPA groups was comparable to that of the Lipiodol-doxorubicin group. CONCLUSION: Even though intraarterial delivery of 3-BrPA shows a dose-related antitumor effect, single session treatment seems to have limited efficacy when compared with the conventional method.
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Animals , Rabbits , Disease Models, Animal , Dose-Response Relationship, Drug , Doxorubicin/administration & dosage , Infusions, Intra-Arterial , Iodized Oil/administration & dosage , Liver Neoplasms, Experimental/drug therapy , Pyruvates/administration & dosage , Statistics, Nonparametric , Tomography, X-Ray ComputedABSTRACT
Objective To investigate the effects of low dosage of β-elemene on the radiosensitivity of rabbit VX2 renal transplant carcinoma model. Methods We took the rabbit VX2 renal transplant carcinoma as the model. Experimental rabbits were divided into three groups: the control group, the radiation group, and the radiation +β-elemene (radiosensitivity) group. The change of tumor was observed by Spiral CT and B ultrasound to compare its regrowth period. The tumor was measured by light microscopy and electron microscopy. Results The tumor in radiosensitivity group was restrained obviously and the sensitization enhancement ratio (SER) of β-elemene was 1.89. Different apoptosis was observed under transmission electron microscopy. Conclusion Low dosage β-elemene can enhance the radiosensitivity of rabbit VX2 renal transplant carcinoma model and induce the apoptosis of tumor cells, but the mechanism needs further study. It promotes apoptosis in mechanisms in vitro.
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Objective:To evaluate the safety of high intensity focused ultrasound(HIFU) for the treatment of implanted rabbit breast tumor.Methods:Forty New England rabbits were randomly divided into the following groups:HIFU treatment group(20),surgery group(10) and control group(10).HIFU ablation was performed at focal peak intensity 11500W/cm with a frequency of 1.6MHz in HIFU group.In surgery group all animals underwent lumpectomy.The animals in control group underwent pseudo-irradiation.The sonograms of target tumor were assessed before and immediately after HIFU ablation.The treated tumor was removed immediately after HIFU,and the lesion was measured by gross examination.Routine serum chemistry examination including hepatic,renal function tests,and serum electrolytes in all animals were performed before and at 1st,3rd,5th and 7th days after treatment.Also tumor metastases were observed after treatment.Results:The gray-scale of target tumors on ultrasound image was low before HIFU and increased immediately after HIFU irradiation.The hyperechoic location was the same as the lesion observed by gross observation.The necrotic lesion completely covered the tumor.No significant differences were observed in hepatic,renal function tests,and serum electrolytes before and after therapy in HIFU group.And these indices were not significantly different in HIFU treatment group,surgery group and control group,respectively.The metastatic rates of HIFU treatment group and surgery group were 20% and 30% respectively.They were significantly different from that of control group(100%,P
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Objective:To explore a method of high successful rate to establish the rabbit VX2 carcinoma model, and monitor the tumor with ultrasound technique.Methods:Tumor block transplanting method was used to make the rabbit VX2 carcinoma model,and verify the tumor in rabbit′s liver with pathological section.Ultrasound technique was applied to detect liver echo, size and echo of tumor,generation and changing of blood vessels in tumor and to find out the characters of the rabbit VX2 carcinoma.Results:The rabbit VX2 carcinoma model was made successfully with tumor block transplanting method, and the success rate was 100%.The ultrasound technique could measure the size of tumor exactly, and it could monitor the changes of the echo and tumor blood vessels in carcinoma exactly at the right time.Conclusion:Tumor block transplanting method is a simple method to make rabbit VX2 carcinoma model with high successful rate. The ultrasound technique is an accurate、convenient and non-invasive method to monitor the carcinoma and blood vessels in tumor.The results provide experimental evidence in evaluating the efficacy of new techniques and therapeutics for liver carcinoma.
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Objective To evaluate the anticancer effect of arsenic trioxide (As 2O 3) on rabbits with hepatic Vx 2 carcinoma by transcatheter arterial infusion (TAI). Methods Rabbits with hepatic Vx 2 carcinoma were treated with As 2O 3 by TAI for 7 d consecutively. The tumor inhibitory rate and the average tumor weight were determined. The morphological changes of the tumor were observed with a transmission electron microscope. bax/bcl 2 and VEGF expressions were examined by immunohistochemistry. Results The average weight of the tumor was 7.99, 6.50, and 4.87 g, and the tumor growth inhibitory rates in the experimental groups were 50.31%, 59 58%, and 69 71%, respectively. Tumor growth was significantly inhibited as compared with that in the NS group ( P