Objective To establish a stable colorectal cancer model in liver specific insulin-like growth factor (IGF)-1 deficient (LID) mice and examine the potential relationship between IGF-1 level and risk of mice constitutional colorectal cancer. Methods ①Establishment of a colorectal cancer model: The LID mice, in which IGF-1 level in circulation was 25% of BALB/c mice. Induction of colorectal cancer was achieved by using the 1,1 Dimethylhydrazine (DMH) with hypodermic injection at transverse part. ②Eighty fresh samples of cancer tissues and adjacent tissues were obtained from LID mice (experimental group) and BALB/c mice (control group). The expression of IGF-1 was studied by immunohistochemical assay (SP method). Results ①Weight loss occurred in both experimental group and control group after injection. Compared with the body weight before injection on 18 weeks and 24 weeks in each group, there were significant differences after injection at the same phase in each group (P＜0.05). ②The results of IGF-1 expression in cancer tissues and adjacent tissues: IGF-1 got a diffuse distribution in cancer cell cytoplasm. The positive expressions of IGF-1 in the cancer tissues and their adjacent cancer tissues were 6/7, 2/7 and 13/16, 7/16 respectively in experimental group and control group. There were significant differences between the cancer tissues and adjacent tissues inside both groups (P＜0.05). There were no significant differences inside both of cancer tissues and adjacent tissues respectively between experimental group and control group (Pgt;0.05). Conclusion In the established colorectal cancer model by DMH, IGF-1 plays an important role in the development and progression of colorectal cancer.
ObjectiveTo establish an animal model of anaplastic thyroid cancer with high metastatic activity as in human body. MethodsHuman anaplastic thyroid cancer cell line TAK was injected into one of the lateral lobes of the thyroid gland, as well as in the subcuitis in a series of nude mice. Mice were sacrificed when found moribund, and autopsy and histology were performed subsequently.ResultsThe implantation of human anaplastic thyroid cancer cells in an ectopic enviroment did not permit expression of metastasis potential. In contrast, intrathyroid implantation did. Lymph node (5/10), lung (3/10) and one metastasis (1/10) were noted upon histological examination. ConclusionAn animal model with high metastatic activity is established when human anaplastic thyroid cancer cell line TAK is implanted orthotopically into nude mice.
Objective To investigate the feasibility and characteristic of tissue engineered testicular prosthesis with highdensity polyethylene(HDPE，trade name: Medpor) and polyglycolic acid(PGA). Methods The chondrocytes were isolated from the swine articular.The PGA scaffold was incorporated with medpor which semidiameters were 6mmand 4mm respectively.Then, the chondrocytes (5×10 7/ml) were seeded onto Medpor-PGA scaffold and cultured for 2 weeks. The ten BALB／C mice were divided into two groups randomly(n=5). In the experimental group, the cell-scaffold construct was implanted into subcutaneous pockets on the back of nude mice. In the control group, the Medpor-PGA scaffold was implanted. The mice of two groups were sacrificed to harvest the newly formed cartilage prosthesis after 8 weeks. Macroscopy, histology and immunohistochemistry observations were made. Results The gross observation showed that on changes were in shape and at size, the color and elasticity were similar to that of normal cartilage and that the cartilage integrated with Medpor in the experimental group; no cartilage formed and fiberlike tissue was found in the control group. HE staining showed that many mature cartilage lacuna formed without blood vessel and some PGA did not degradated completely. Toluidine blue staining showed extracellular matrix had metachromia. Safranin O-fast green staining showed that many proteoglycan deposited and collagen type Ⅱ expression was bly positive. In the control group, Medpor was encapsulated by fiber tissue with rich blood vessel. Conclusion The newly formed complex of Medpor-PGA and cells was very similar to testicle in gross view and to normal cartilage in histology. This pilot technique of creating testicular prosthesis by incorporating tissue-engineered cartilage with Medpor demonstrated success.
Objective To investigate the intervention effect of 3-phosphoinositede dependent protein kinase-1 (PDK1) inhibitor on prostaglandin E2 (PGE2) in smoking-induced chronic obstructive pulmonary disease (COPD) mice. Methods Fifty C57BL/6 male mice were randomly divided into normal control group, smoking group, smoking +low dose PDK1 inhibitor group, smoking + medium dose PDK1 inhibitor group and high dose PDK1 inhibitor group with 10 mice in each group. The mice in the normal control group inhaled phosphate-buffered saline twice a day for 12 weeks, and the mice in the smoking group were fumigated twice a day, 5 days per week for 12 weeks, and the other three groups were given intraperitoneal injection of low-dose PDK1 inhibitor OSU-03012 (0.25 mg/kg), medium-dose PDK1 inhibitor (0.5 mg/kg) and high-dose PDK1 inhibitor (1.0 mg/kg) respectively before smoking. After smoking, lung function was tested, the bronchoalveolar lavage fluid (BALF) of each mouse was taken for cell count, the PGE2 in serum and BALF of mice was determined by enzyme linked immunosorbent assay, and the lung tissue of mice was sectioned with paraffin and stained by hematoxylin-eosin (HE), and pathological changes were observed under microscope. Results Compared with the control group, FEV100/FVC and FEV200/FVC of the mice in each smoking group were significantly decreased (P<0.05); The number of cells in BALF of smoking group was significantly higher than that of normal control group (P<0.05). There was no significant difference in the total number of BALF cells, the proportion of neutrophils and macrophages between the smoking + low-dose PDK1 inhibitor group and the smoking group. However, the total number of BALF cells and the proportion of neutrophils in the smoking + medium dose PDK1 inhibitor group and the high dose PDK1 inhibitor group gradually decreased, while the proportion of macrophages gradually increased, compared with the normal control group, the PGE2 concentrations of serum and BALF in the smoking group and the smoking + PDK1 inhibitor group were significantly higher than those in the control group. Compared with the smoking group, the PGE2 concentrations of serum and BALF in the middle and high dose PDK1 inhibitor groups were significantly lower than those in the smoking group. HE staining of lung tissue showed that there were a large number of inflammatory cell infiltration, alveolar cavity dilatation, alveolar wall rupture and fusion, alveolar formation, significant decrease in the number of alveoli and other pathological changes in the smoking group, which were consistent with the pathological changes of COPD. The inflammatory cell infiltration, mucus obstruction and alveolar dilatation were slightly alleviated in the smoking + low-dose PDK1 inhibitor group, while the inflammatory cell infiltration, alveolar wall thinning and alveolar dilatation were improved in both the medium-dose inhibitor group and the high-dose inhibitor group, and the improvement was more obvious in the high-dose inhibitor group. Conclusion The lung function of the smoked COPD mouse decreases, the airway inflammation is obvious, and the secretion of PGE2 is also increased, while the use of PDK1 inhibitor could reduce the secretion of PGE2, reduce airway inflammation and pathological changes, and improve lung function in a dose-dependent manner.
ObjectiveTo discuss the effects of coix seed extract injection on rate of tumor of C57 mice liver cancer model, tumor size, and serum IL-6. MethodsUsing chemical carcinogens diethyl nitrosamine (DEN) to establish the mice model of liver cancer, liver cancer mouse model to coix seed extract was given observation of C57 mice liver cancer model come tumor formation rate, tumor growth, and the change of serum IL-6. ResultsC57 mice after intraperitoneal injection of coix seed extract injection model of liver cancer tumor rate (55.6%) significantly lower than the DEN group (87.5%), P < 0.01; tumor diameter[(0.3±0.05) cm] was lower than that in group DEN[(0.8±0.06) cm], P < 0.01. The serum level of IL-6 in C57 mice after treated with coix seed extract significantly lower than that in group DEN (P < 0.01). ConclusionCoix seed extract can effectively inhibit the tumor rate and the growth of tumor in hepatocellular carcinoma model of C57 mice, and decrease the level of serum IL-6.
ObjectiveTo study the feasibility of human adipose-derived stem cells (hADSCs) combined with small intestinal submucosa powder (SISP)/chitosan chloride (CSCl)-β-glycerol phosphate disodium (GP)-hydroxyethyl cellulose (HEC) for adipose tissue engineering. MethodshADSCs were isolated from human breast fat with collagenase type I digestion, and the third passage hADSCs were mixed with SISP/CSCl-GP-HEC at a density of 1×106 cells/mL. Twenty-four healthy female nude mice of 5 weeks old were randomly divided into experimental group (n=12) and control group (n=12), and the mice were subcutaneously injected with 1 mL hADSCs+SISP/CSCl-GP-HEC or SISP/CSCl-GP-HEC respectively at the neck. The degradation rate was evaluated by implant volume measurement at 0, 1, 2, 4, and 8 weeks. Three mice were euthanized at 1, 2, 4, and 8 weeks respectively for general, histological, and immunohistochemical observations. The ability of adipogenesis (Oil O staining), angiopoiesis (CD31), and localized the hADSCs (immunostaining for human Vimentin) were identified. ResultsThe volume of implants of both groups decreased with time, but it was greater in experimental group than the control group, showing significant difference at 8 weeks (t=3.348, P=0.029). The general observation showed that the border of implants was clear with no adhesion at each time point;fat-liked new tissues were observed with capillaries on the surface at 8 weeks in 2 groups. The histological examinations showed that the structure of implants got compact gradually after injection, and SISP gradually degraded with slower degradation speed in experimental group;adipose tissue began to form, and some mature adipose tissue was observed at 8 weeks in the experimental group. The Oil O staining positive area of experimental group was greater than that of the control group at each time point, showing significant difference at 8 weeks (t=3.411, P=0.027). Immunohistochemical staining for Vemintin showed that hADSCs could survive at each time point in the experimental group;angiogenesis was most remarkable at 2 weeks, showing no significant differences in CD31 possitive area between 2 groups (P>0.05), but angiogenesis was more homogeneous in experimental group. ConclusionSISP/CSCl-GP-HEC can use as scaffolds for hADSCs to reconstruct tissue engineered adipose.
Objective To determine the effect of insulin-like growth factor-1 (IGF-1) on angiogenesis in mouse breast cancer model of lower and normal serum IGF-1 levels after using angiogenesis inhibitor ginsenoside Rg3 （GS Rg3）. Methods The breast cancer models were established in control mice and liver specific IGF-1 deficient (LID) mice by feeding DMBA and were treated with GS Rg3. Vascular endothelial growth factor (VEGF) and F8-RAg were detected by immunohistochemical method in breast cancer tissues. IGF-1 gene and angiogenesis relating genes were detected by gene chip in breast cancer and normal breast tissue. Results The incidence rate of breast cancer in LID mice was lower than that in control mice (P＜0.05). VEGF expression and microvessel density of LID mice were lower than those in control mice (P＜0.05). Compared to the control mice, IGF-1, FGF-1, TGF-β1 and HGF genes were increased, and FGFR-2, PDGF-A and PDGF-B genes were decreased in breast cancer of LID mice. After GS Rg3 treatment, VEGFa, EGF, EGFR, PDGF-A and FGFR-2 genes were increased, IGF-1 and TGF-β1 genes were decreased in breast cancer of LID mice compared with the control mice. Conclusion IGF-1 may be involved in mouse breast cancer progression and associated with the growth of blood vessels. Angiogenesis inhibitor may play an antitumor role by IGF-1 and TGF-β1.
A multiple-stimuli-responsive drug-conjugated cross-linked micelles was prepared by radical copolymerization. The chemical structure, morphology, and size of the cross-linked micelles were characterized, and the drug loading of the micelle was calculated. The experimental results indicated that the hydrodynamic size of the drug-loaded micelles were about 100 nm, and the as prepared micelles could be degraded and swelled in presence of reducing glutathione (GSH). The low critical solution temperature (LCST) of the micelle was around 39.4℃. According to the experimental results, the micelles will shrink at temperature above the LCST. Subsequently, the accumulative drug release rate was up to 91.78% under acidic (pH 5.0), reductive (GSH 10 mmol/L) and high temperature (42.0℃) conditions mimicking the tumor microenvironment, while a relatively low release rate of 1.12% was observed without stimulation. The drug-conjugated cross-linked micelles showed a strong cell uptake behavior. In the cytotoxicity assay, the micelles exhibited effective anti-cancer activity and excellent biocompatibility. In brief, the experimental results show that the as-prepared drug-conjugated cross-linked micelle exhibits multiple stimuli-responsiveness, which holds great promise for anti-cancer drug delivery.
ObjectiveTo evaluate the feasibility of monitoring of permanent middle cerebral artery occlusion (MCAO) model in C57BL/6 mice by Laser Doppler flowmetry. MethodsC57BL/6 mice were divided into 2 groups randomly:sham group and permanent MCAO group. Permanent MCAO model was established with the method of suture inserted into the internal carotid artery. Sufficiency of MCAO was monitored by Laser Doppler flowmetry during ischemia in mice. The neurological deficit score was assessed and the cerebral infarction size was measured by 2, 3, 5-triphenytetrazolium chloride (TTC) staining technique twenty-four hours after MCAO. ResultsIn the MCAO group, the local blood flow was decreased from the preoperative value of (186.78±62.50) PU to the postoperative value of (25.80±7.66) PU. Cerebral blood flow was reduced by 90.4% during MCAO. The neurological deficit score was 2.48±0.36. The cerebral infarction area accounted for 39.79% by TTC staining. However, the cerebral blood flow fluctuations were not reduced and the neurological deficit score was found normal in the sham group. Furthermore, there was no cerebral infarction lesion in the sham group. ConclusionMonitoring by Laser Doppler flowmetry is efficient for evaluating the success rate of MCAO.
ObjectiveTo study the expression of lipid associated with neutrophil gelatinase associated lipocalin (NGAL) in nude mice orthotopic pancreatic cancer tissues and the relationship between the occurred and development of pancreatic cancer. MethodsThe expressions of NGAL mRNA and protein of pancreatic cancer tissues and their adjacent tissues, and normal pancreatic tissues in nude mice were detected by using RT-PCR and immunohistochemical methods. ResultsThe expressions of NGAL mRNA in pancreatic cancer tissues and adjacent tissues were significantly higher than that in normal pancreatic tissues (P < 0.05), and the expression of NGAL mRNA in pancreatic carcinoma tissues was significantly higher than that in para carcinoma tissues (P < 0.05). The strong positive expression rate of NGAL protein in pancreatic carcinoma tissues was significantly higher than thoes in para carcinoma tissues and normal pancreatic tissues (P < 0.05). ConclusionsNGAL is highly expressed in pancreatic cancer tissues, and NGAL may be an important regulatory factor in the development of pancreatic cancer.