OBJECTIVE: To evaluate the impact of energy and access methods on extrahepatic tumor spreading and the ablation zone in an ex vivo subcapsular tumor mimic model with a risk of extrahepatic tumor spreading. MATERIALS AND METHODS: Forty-two tumor-mimics were created in bovine liver blocks by injecting a mixture of iodine contrast material just below the liver capsule. Radiofrequency (RF) ablations were performed using an electrode placed parallel or perpendicular to hepatic surface through the tumor mimic with low- and high-power protocols (groups 1 and 2, respectively). Computed tomography (CT) scans were performed before and after ablation. The presence of contrast leak on the hepatic surface on CT, size of ablation zone, and timing of the first roll-off and popping sound were compared between the groups. RESULTS: With parallel access, one contrast leak in group 1 (1/10, 10%) and nine in group 2 (9/10, 90%) (p < 0.001) were identified on post-ablation CT. With perpendicular access, six contrast leaks were identified in each group (6/11, 54.5%). The first roll-off and popping sound were significantly delayed in group 1 irrespective of the access method (p = 0.002). No statistical difference in the size of the ablation zone of the liver specimen was observed between the two groups (p = 0.247). CONCLUSION: Low-power RF ablation with parallel access is proposed to be effective and safe from extrahepatic tumor spreading in RF ablation of a solid hepatic tumor in the subcapsular location. Perpendicular placement of an electrode to the capsule is associated with a risk of extrahepatic tumor spreading regardless of the power applied.
Animals ; Catheter Ablation ; Electrodes ; Iodine ; Liver ; Liver Neoplasms, Experimental ; Methods ; Neoplasm Seeding

OBJECTIVETo study whether the ethanol extract of Phellinus merrillii (EPM) has chemopreventive potential against liver carcinogenesis.

METHODSThirty male Spraque-Dawley rats were randomly divided into control group, EPM control group, hepatocarcinoma control group, low-dose EPM group and high-dose EPM group, 6 in each group. Using the Solt and Farber protocol in a rat model of hepatocarcinogenesis, the chemopreventive effect of EPM on diethylnitrosamine (DEN)-initiated, 2-acetylaminofluorene (2-AAF) and partial hepatectomy (PH)-promoted liver carcinogenesis in rats was evaluated. Basic pathophysiological and histological examinations, together with the serum levels of glutamic oxaloacetic transaminase (sGOT), glutamic pyruvic transaminase (sGPT) and gamma-glutamyl transpeptidase (γ-GT) were measured.

RESULTSTreatment of EPM at the concentration of 2 g/kg body weight in the diet for 8 weeks clearly prevented the development of carcinogenesis and reduced the levels of sGOT, sGPT, and serum γ-GT of rats as compared with the hepatocarcinoma control group (P<0.05 or P<0.01). These phenotypes were accompanied by a significant increase in natural killer cell activity.

CONCLUSIONEPM showed a strong liver preventive effect against DEN+2-AAF+PH-induced hepatocarcinogenesis in a rat model.

2-Acetylaminofluorene ; Animals ; Basidiomycota ; chemistry ; Carcinogenesis ; chemically induced ; Cytoprotection ; drug effects ; Diethylnitrosamine ; Ethanol ; chemistry ; Liver Neoplasms, Experimental ; chemically induced ; prevention & control ; Male ; Plant Extracts ; chemistry ; pharmacology ; Protective Agents ; pharmacology ; Rats ; Rats, Sprague-Dawley

The function of the spleen in tumor development has been investigated for years. The relationship of the spleen with hepatocellular carcinoma (HCC), a huge health burden worldwide, however, remains unknown. The present study aimed to examine the effect of splenectomy on the development of HCC and the possible mechanism. Mouse hepatic carcinoma lines H22 and Hepa1-6 as well as BALB/c and C57 mice were used to establish orthotopic and metastatic mouse models of liver cancer. Mice were divided into four groups, including control group, splenectomy control group (S group), tumor group (T group) and tumor plus splenectomy group (T+S group). Tumor growth, metastases and overall survival were assessed at determined time points. Meanwhile, myeloid-derived suppressor cells (MDSCs) were isolated from the peripheral blood (PB), the spleen and liver tumors, and then measured by flow cytometery. It was found that liver cancer led to splenomegaly, and increased the percentage of MDSCs in the PB and spleen in the mouse models. Splenectomy inhibited the growth and progression of liver cancer and prolonged the overall survival time of orthotopic and metastatic models, which was accompanied by decreased proportion of MDSCs in the PB and tumors of liver cancer-bearing mouse. It was suggested that splenectomy could be considered an adjuvant therapy to treat liver cancer.
Animals ; Carcinoma, Hepatocellular ; physiopathology ; surgery ; Cell Line, Tumor ; Flow Cytometry ; Humans ; Liver Neoplasms ; physiopathology ; surgery ; Mice ; Myeloid-Derived Suppressor Cells ; pathology ; Neoplasms, Experimental ; physiopathology ; surgery ; Spleen ; physiopathology ; surgery ; Splenectomy ; methods

OBJECTIVETo investigate the anticancer efficacy and the hepatic and renal toxicity of As2O3-lipiodol emulsion via transarterial embolization in a rabbit VX2 liver tumor model.

METHODSVX2 tumors were implanted in rabbit livers successfully, followed by transarterial embolization with high-dose As2O3(5 mg/kg with 0.2 mL lipiodol, n=10), low-dose As2O3(1 mg/kg with 0.2 mL lipiodol, n=10), and control(0.2 mL lipiodol, n=10). The growth ratios and microvessel densities(MVDs) of the tumors were estimated by multi-row spiral CT and CD34 immunohistochemical staining, respectively. Hepatic and renal function was also evaluated by means of blood biochemical analysis.

RESULTSThe growth ratios of the tumors differed significantly among three groups(P<0.01). The high-dose and low dose group showed significantly lower tumor growth ratios[44.05%(-36.40%~64.60%), 95.20%(-11.60%~159.40%)] than control group[145.55%(98.90%~250.30%), all P<0.05]. The MVDs of the tumors were significantly lower in the high-dose(21.4±10.6) and low-dose group(34.1±12.0) than those in control group(57.9±16.1,all P<0.05). The levels of blood ALT and AST obtained 28 days after transarterial embolization were significantly lower in the high-dose[(25.50±12.37)U/L,(24.25±10.89)U/L] and low-dose group[(45.00±14.04)U/L,(35.22±11.86)U/L] than in control group[(79.12±30.52)U/L,(75.25±25.89)U/L, all P<0.05].

CONCLUSIONAs2O3-lipiodol emulsion via transarterial embolization has anticancer effect without significant hepatic and renal functional damage in rabbit VX2 liver tumors.

Animals ; Antineoplastic Agents ; pharmacology ; Arsenicals ; pharmacology ; Embolization, Therapeutic ; Emulsions ; pharmacology ; Ethiodized Oil ; pharmacology ; Liver Neoplasms, Experimental ; drug therapy ; Oxides ; pharmacology ; Rabbits ; Tomography, Spiral Computed

OBJECTIVE: To observe the micromorphological changes of ultrastructure, apoptosis-related proteins expression and tumor cell apoptosis after ablation with the high-intensity focused ultrasound (HIFU), and to explore the mechanisms responsible for the thermal and non-thermal effect.
 METHODS: Forty rabbits with hepatic VX2 tumors were randomly divided into a thermal group (n=20) and a non-thermal group (n=20), and were subjected to HIFU ablation with thermal or non-thermal condition, respectively. Five animals in each group were sacrificed on the 1st, 3rd, 7th or 14th day after the ablation. The changes of ultrastructure, apoptosis-related proteins expression and tumor cell apoptosis were detected.
 RESULTS: The results of transmission electron microscope (TEM) revealed more severe injury on tissue and cells in the non-thermal group than that in the thermal group. The changes of apoptosis-related proteins expression and tumor cell apoptosis in transient zone were significantly different in comparison with that in the ablated area or peripheral area between the two groups. The expression of vascular endothelial growth factor (VEGF) was at low level on the 1st and 3rd day and elevated gradually on the 7th and 14th day, with no significant difference (all P>0.05). The expression of caspase-3 reached peak on the 3rd day and decreased on the 7th and 14th day. It was significantly higher in the non-thermal group than that in the thermal group on the 3rd and 7th day (all P<0.05). The expression of NF-κB was elevated from the 3rd day and reached peak on the 7th day while decreased on the 14th day. There was no significant difference at every time point between the 2 groups (all P>0.05). The apoptosis index in the non-thermal group and the thermal group on the 3rd and 7th day were (28.60±1.14)% vs (21.80±1.92)% and (21.00±1.58)% vs (14.80±1.48)%, respectively. It was higher in the non-thermal group than that in the thermal group (both P<0.01).
 CONCLUSION Both the thermal and the non-thermal effect of HIFU can induce apoptosis in transient zone, but the latter have a stronger effect.
Animals ; Apoptosis ; Caspase 3 ; metabolism ; High-Intensity Focused Ultrasound Ablation ; Liver Neoplasms ; pathology ; ultrastructure ; NF-kappa B ; metabolism ; Neoplasms, Experimental ; pathology ; ultrastructure ; Rabbits ; Vascular Endothelial Growth Factor A ; metabolism

Tumors are believed to consist of a heterogeneous population of tumor cells originating from rare cancer stem cells (CSCs). However, emerging evidence suggests that tumor may also originate from non-CSCs. To support this viewpoint, we are here to present definitive evidence indicating that the number of tumorigenic tumor cells is greater than that of CSCs in tumor, and tumor can also derive from non-CSCs. To achieve this, an idealized mathematical model was employed in the present study and theoretical calculation revealed that non-CSCs could initiate the occurrence of tumor if their proliferation potential was adequate. Further, experimental studies demonstrated that 17.7%, 38.6% and 5.2% of tumor cells in murine B16 solid melanoma, H22 hepatoma and Lewis lung carcinoma, respectively, were potentially tumorigenic. Thus, based on the aforementioned findings, we propose that the scarce CSCs, if exist, are not the sole source of a tumor.
Algorithms ; Animals ; Carcinogenesis ; pathology ; Carcinoma, Lewis Lung ; pathology ; Cell Differentiation ; Cell Line, Tumor ; Cell Proliferation ; Liver Neoplasms, Experimental ; pathology ; Melanoma, Experimental ; pathology ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Models, Biological ; Neoplasms, Experimental ; pathology ; Neoplastic Stem Cells ; pathology ; Time Factors ; Tumor Stem Cell Assay ; methods

OBJECTIVETo study the effect of spleen lymphocytes on the splenomegaly by hepatocellular carcinoma-bearing mouse model.

METHODSCell counts, cell cycle distribution, the percentage of lymphocytes subsets and the levels of IL-2 were measured, and two-dimensional gel electrophoresis (2-DE) was used to investigate the relationship between spleen lymphocytes and splenomegaly in hepatocellular carcinoma-bearing mice.

RESULTSCompared with the normal group, the thymus was obviously atrophied and the spleen was significantly enlarged in the tumor-bearing group. Correlation study showed that the number of whole spleen cells was positively correlated with the splenic index. The cell diameter and cell-cycle phase distribution of splenocytes in the tumor-bearing group showed no significant difference compared to the normal group. The percentage of CD3+ T lymphocytes and CD8+ T lymphocytes in spleen and peripheral blood of tumor-bearing mice were substantially higher than that in the normal mice. Meanwhile, the IL-2 level was also higher in the tumor-bearing group than in the normal group. Furthermore, two dysregulated protein, β-actin and S100-A9 were identified in spleen lymphocytes from H22-bearing mice, which were closely related to cellular motility.

CONCLUSIONIt is suggested that dysregulated β-actin and S100-A9 can result in recirculating T lymphocytes trapped in the spleen, which may explain the underlying cause of splenomegaly in H22-bearing mice.

Animals ; Carcinoma, Hepatocellular ; complications ; Cell Cycle ; Female ; Liver Neoplasms ; complications ; Lymphocytes ; physiology ; Mice ; Mice, Inbred ICR ; Neoplasms, Experimental ; therapy ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Spleen ; cytology ; pathology ; Splenomegaly ; etiology ; therapy ; Thymus Gland

Alkaloids ; pharmacology ; Animals ; Liver Neoplasms, Experimental ; enzymology ; prevention & control ; Quinolizines ; pharmacology ; Rats ; Selenium ; pharmacology ; Telomerase ; metabolism ; Yeast, Dried ; pharmacology

OBJECTIVETo establish a modified rat model of liver cancer with concurrent cirrhosis for the study of carcinogenesis characteristics and drug intervention of liver cancer.

METHODSFifty male Wistar rats weighing 100-120 g were randomly divided into normal control group (20 rats) and model group (30 rats). In the model group, the rats were subjected to intraperitoneal injection of 50 mg/kg DEN N-diethylnitrosamine (DEN) twice a week for 4 consecutive weeks, followed then by weekly injections for another 10 weeks. The control rats received injections of 0.1 ml saline in the same manner. At 2, 4, 8, 12, 14, and 18 weeks, 3 rats from each group were sacrificed for assessing tumor formation and liver cirrhosis.

RESULTSLiver cancer with concurrent cirrhosis was induced successfully after 14 weeks of DEN injections. At the 14th week, 3 out of the 5 rats were found to have cirrhosis and LC, and at the 18th week, all the 3 rats examined had cirrhosis and liver cancer. The total carcinogenesis rate in the rats was 75% at 18 weeks with an overall mortality of 33%.

CONCLUSIONThis approach to establishing rat models of liver cancer with concurrent cirrhosis requires simple operation, shortens the time of carcinogenesis, and ensures a high success rate of carcinogenesis and a low mortality rate. The carcinogenesis characteristics in this model are similar to those in human.

Animals ; Liver Cirrhosis, Experimental ; complications ; pathology ; Liver Neoplasms, Experimental ; etiology ; pathology ; Male ; Rats ; Rats, Wistar

This study is to investigate the anti-tumor activities of a novel cyclophosphamide derivate 4, 6-diphenyl cyclophosphamide (9b) in vivo and in vitro, and its possible mechanism of action. The inhibitory effects of 9b on human hepatoma cell line HepG2, human breast carcinoma cell line MCF-7 and human myeloid leukemia cell line K562 were measured by MTT assay in vitro. Cell cycle distribution and apoptotic rate were evaluated by flow cytometry. To evaluate the anti-tumor effect of 9b in vivo, mouse model bearing inoculated H22 tumor was established. The results indicated that 9b could inhibit the proliferation of HepG2, MCF-7 and K562 cells in a dose and time dependent manner. The ICo50 values of 9b were 32.34 micromol.L-1 to HepG2 cells, 87.07 micromol.L-1 to MCF-7 cells and 149.10 micromol.L-1 to K562 cells after incubation for 48 h. The results of flow cytometry indicated that after being treated for 48 h with different concentrations of 9b, the ratios of HepG2, MCF-7 cells at the Go/G1 phase and K562 cells at the G0/Gl phase and G2/M phase increased significantly compared with control group, and the apoptotic rate increased with the increase of the concentration of 9b. 9b could significantly reduce tumor weight of H22 solid tumor mouse model in vivo. To summarize, 9b showed significantly anti-tumor activity in vivo and in vitro, of which the mechanism might be associated with the change of cell cycle distribution and induction of tumor cell apoptosis.
Animals ; Antineoplastic Agents, Alkylating ; chemistry ; pharmacology ; Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cyclophosphamide ; analogs & derivatives ; chemistry ; pharmacology ; Dose-Response Relationship, Drug ; Female ; Humans ; Inhibitory Concentration 50 ; Liver Neoplasms, Experimental ; pathology ; Male ; Mice ; Molecular Structure ; Random Allocation ; Tumor Burden ; drug effects