ObjectiveTo study the apoptotic induction effect of Thapsigargin on estrogen receptor positive human breast cancer cell lines MCF7. MethodsCells were treated with Thapsigargin and 5FU in vitro. The rate of cell apoptosis and distribution of cell cycle were detected on flow cytometry. The cell viability was measured by MTT assay and ultrastructural changes in apoptotic cells were confirmed by transmission electron microscopy.ResultsThapsigargin could increase the rates both of cell apoptosis and growth supression of MCF7 cells induced by 5FU and alter the distribution of cell cycle. Under electron microscope, apoptotic bodies in MCF7 cells considerably increased.ConclusionThapsigargin apparently enhances the effect of apoptotic induction of 5FU on MCF7 cells, it is worthy of being further studied.
Objective To investigate a new grafting material of bone xenograft with b bone inductive and conductive capacity. Methods Based on successful clinical application of the reconstituted bone xenograft (RBX), a new xenograft was made by combining recombinant human bone morphogenetic protein-2 (rhBMP-2) with antigen-free bovine cancellous bone (BCB). Sixty male BALB/C mice aged 4 weeks were divided into study group of 30 and control group of 30 randomly. rhBMP-2 / BCB was implanted in the left thigh muscle pouch in the study group andBCB in the control group. The mice were sacrificed at 7 d, 14d and 21d after implantation. Inductivity of rhBMP-2/BCB was detected by histological observation and biochemical determination of the samples. Results Histological examinationshowed that rhBMP-2/BCB induced chondrogenesis on the 7th day, with woven boneformed on the 14th day, and lamellar bone and marrow on the 21st day, while BCBfailed to induce chondrogenesis or osteogenesis on the 7th, 14th and 21st days. The alkaline phosphatase activities and calcium content in study group were higher than those in control group with significant difference (P＜0.01). Conclusion rhBMP-2/BCB is an ideal grafting material with b bone inductive and conductive capacity without evoking immune reaction.
Objective To establ ish a new induction method from human embryonic stem cells (hESCs) differentiating into hepatocyte-l ike cells using an adherent culture system with single-step induction. Methods Undifferentiated hESCs were cultured on Matrigel-coated culture plates for 4 days, hepatic differentiation was initiated at 60%-70% confluence by adding Activin A for 5 days. Then the induction medium was replaced by hepatocyte induction medium (HIM) supplemented with fibroblast growth factor 1 (FGF-1) and bone morphogenetic protein 4 (BMP-4) for another 6 days. Finally, the cells were treated with HIM adding hepatocyte growth factor (HGF) and Oncostatin M (OSM) for 5-7 days. The characteristics of differentiated cells were determined by morphology, immunofluorescence staining, RT-PCR, and Periodicacid- Schiff (PAS) test. Results Differentiated cells treated with Activin A, FGF-1, BMP-4, HGF, and OSM sequentially were morphologically larger and became spherical, oval or polygon. Some cells had 2 or 3 nuclei, suggesting that the cells have a hepatocyte-l ike morphology. Differentiated cells at first induction stage could be stained positive by SOX17 and Forkhead (FOX)A2 after induction by Activin A. Then they turned to be α fetoprotein (AFP) and α1 antitripsin positive cells at second induction stage after induction by FGF-1 and BMP-4. Finally, the differentiated cells treated with HGF and OSM showed PAS possitive for glycogen detection. The differentiated cells at various stages also expressed at early (SOX17, FOXA2, and GATA-4),middle (AFP, albumin, and cytokeratin 18), and mature (alcohol dehydrogenase 1C and Cytochrome P4501B1) stage hepatic genes, respectively. Conclusion Using a simple-step induction method and by suppl ied with cytokines consequently, hESCs can be induced to differentiate into hepatocyte-l ike cells. The differentiation method can provide seed cells for hepatic tissue engineering or cell-therapy.
ObjectiveTo explore the role and significance of hypoxia inducible factor lα (HIF-lα) and hypoxia microenvironment in the pathogenesis of post-traumatic heterotopic ossification by detecting the expression of HIF-lα in rat model of heterotopic ossification after Achilles tenotomy. MethodsA total of 140 male Sprague Dawley rats, aged 8-10 weeks, and weighing (210.1±10.6) g, were randomly divided into experimental group (n=70) and control group (n=70). In experimental group, the Achilles tendon was cut off and clamped to prepare post-traumatic heterotopic ossification model; in control group, only Achilles tendon was exposed. The general condition of rats was observed after operation, and at 2, 3, 4, 5, 6, 7, 8, 10, 12, and 14 days after operation, the Achilles tendon tissue was harvested from 6 rats for gross observation, histological observation, and immunohistochemical staining observation, and real-time fluorescence quantitative PCR and Western blot were used to detect the expressions of HIF-lα gene and protein at different time points in 2 groups. The X-ray films were taken and histological examination was done at 10 weeks after operation to evaluate the formation of heterotopic ossification. ResultsDuring the experiment, 1 rat died in experimental group at 3 days after operation, and the other rats survived to the end of the experiment. Gross and histological staining showed that the Achilles tendon had no obvious change, with normal tendon structure in control group at each time point. In experimental group, atrophy and necrosis of Achilles tendon stump were observed, with infiltration of inflammatory cells; and the hardness of Achilles tendon tissue gradually increased with the time; there were a large number of irregular connective tissue and cartilage cells. When compared with control group, the HIF-lα mRNA and protein expressions were significantly increased in experimental group at each time point (P < 0.05). Immunohistochemical staining showed that HIF-lα was positive in experimental group. According to the results of X-ray films and histological examination at 10 weeks after operation, heterotopic ossification was found in experimental group, but no heterotopic ossification in control group. ConclusionThe expression of HIF-lα significantly increases at early stage of post-traumatic heterotopic ossification after Achilles tenotomy, suggesting that the local hypoxia microenvironment plays an important role in the pathogenesis of heterotopic ossification.
Objective To explore the regulator factor of osteogenes is induced by the fibroblast in vitro so as to provide enough seeding cells for the bon e tissue engineering. Methods The fibroblasts were isolated and purified from granu lation of New Zealand rabbits, and they were incubated in the media offibronectin (FN) 10, 20, 40, 60 and 80 μg/ml, respectively, in the experimenta l grou ps 1- 5，but there was no FN in the control group. The markers for osteogenic features were investigated by fibroblast morphogenesis,calcium nodules formationratios,labeling of tetracycline fluorescence, labeling of 3H-TdR, determination of o steocaline, and labeling of 3H-proline within 2 weeks. Results The morphologic al changes of the fibroblasts were manifested as transference from a long spindle to a round or multiple form, shifted nucleus increased in number, confluenced and formed multilayered structure. There was a piling-up of calcium crystals that were gradually merged into foggy substances. The foggy substances increased and formed nodules. The calcium nodules formation ratios were as follows: 15.35％± 3.45％in the control group, and 53.73％± 9.49％, 75.21％± 9.80％, 98.34％± 15.2 0％, 61.83％± 10.04％, and 45.11％± 8.70％ in the experimental groups 1.5 ,respectively. There was a significant difference between the control group and the 5 experimental groups at 14 days (Plt;0.05), and a significant differenc e be tween the experimental group 3 and the other experimental groups at 14 days (Plt;0.05). The histochemical study on the nodules with the specific labeling of tet racycline fluorescence indicated that the nodules were composed of new bones. Conclusion Fibronectin can stimulate the fibroblast to prolifer ate, secrete osteocaline, and synthesize collagen fibrils. Fibronectin, in an optimal dose of 40 -60 μg/ml, is capable of inducing the fibroblast to form the bone.
ObjectiveTo study the effect of tumor associated neutrophil (TAN) releasing a proliferation-inducing ligand (APRIL) on the proliferation of pancreatic cancer cells in microenvironment.Methods① The expressions of APRIL in neutrophils (differentiated by HL-60 cell) and TAN cells were detected by use ELISA. ② The expressions of APRIL receptors B cell maturation antigen (BCMA) and trans-membrane activator and CAML interactor (TACI) in pancreatic cancer cell line PANC-1 were confirmed by use Western blotting. ③ Pancreatic cancer PANC-1 cells were co-cultured with TAN, and divided into a PANC-1 control group (referred to as the control group), a PANC-1+TAN treatment group (referred to as the PANC-1+TAN group), PANC-1+TAN+APRIL antibody treatment group (referred to as PANC-1+TAN+APRIL group), and PANC-1+rtificial recombinant APRIL protein (rAPRIL) treatment group (referred to as PANC-1+rAPRIL group). The CCK8 method was used to determine TAN release of APRIL on PANC-1 effect of cell proliferation activity.Results① The APRIL content in the culture medium of TAN cell group was higher than that of neutrophil group [(556.20±84.38) pg/mL vs. (377.17±57.07) pg/mL, P=0.038]. ② PANC-1 cells express the receptors BCMA and TACI of APRIL. ③ PANC-1 cell activity of PANC-1+TAN group and PANC-1+rAPRIL group [(126.80±1.42)%, (168.95±12.54)%] were significantly higher than the control group [(100 ± 0.00)%, P<0.05, P<0.001], the activity of PANC-1 cells in the PANC-1+TAN group was significantly higher than that in the PANC-1+TAN+APRIL group [(86.29 ± 12.20)%, P=0.003] and significantly lower than that of PANC-1+rAPRIL group (P=0.002), the activity of PANC-1 cells in PANC-1+rAPRIL group was significantly higher than that in PANC-1+TAN+APRIL antibody group (P<0.001).ConclusionIn the microenvironment of pancreatic cancer, the release of APRIL from TAN increases, which promotes the proliferative activity of PANC-1 in pancreatic cancer cells, which provides a new idea for the mechanism research and treatment of pancreatic cancer progression.
目的:观察依托咪酯持续输注用于麻醉诱导和维持对肾上腺皮质功能的抑制程度以及评价是否会造成严重不良后果。方法:择期行普外手术患者60例,随机分成依托咪酯组(E组)和异丙酚组(P组)。两组患者常规麻醉诱导后,E组和P组分别采用瑞芬太尼0.1～0.4 μg/kg·min,复合依托咪酯或异丙酚维持,据BIS值调整依托咪酯或异丙酚的输注速率。分别测定麻醉前,手术结束时,术后24 h,术后48 h患者血清皮质醇浓度,记录各组的血压,心率,睁眼时间,拔管时间和术后不良反应。结果:与麻醉前比较,E组和P组患者在手术结束时皮质醇浓度均降低,但E组降低更明显(Plt;0.05),48 h后恢复正常甚至高于麻醉前水平;与诱导前相比,异丙酚组患者诱导后平均动脉压(MAP)明显低于诱导前,而依托咪酯组无明显变化;E组的拔管时间比P组长(Plt;0.05),而睁眼时间无明显差异(Pgt;0.05).结论:1依托咪酯和异丙酚均能抑制患者肾上腺皮质功能,且依托咪酯组更为明显,在术后48 h基本恢复正常,甚至高于术前水平。2依托咪酯在麻醉诱导和维持中比异丙酚具有血流动力学稳定性。3依托咪酯持续输注用于全身麻醉维持并不造成围术期严重不良后果。
ObjectiveTo explore the effects of hypoxia inducible factor-1 alpha (HIF-1α) on the reverse differentiation of hepatocellular carcinoma cells into liver cancer stem cells, and the maintenance of malignant biological behavior in hypoxic environment.MethodsCD133-negative cells in HepG2 cells were separated by immunomagnetic beads and divided into two groups. The cells of siRNA group were transfected with siRNA-HIF-1α to silence the expression of HIF-1α gene, while cells of the blank control group did not transfect any siRNA fragments. The two groups of cells were cultured under normal and hypoxic conditions respectively. MTT, cloning and Transwell chamber experiments were used to detect the proliferation and invasion ability of cells. Western blot and real-time PCR (RT-PCR) were used to detect the expressions of HIF-1α, CD133, CD90, and CD44 protein and mRNA in cells.ResultsMTT results showed that the cell proliferation rate increased with the prolongation of hypoxia in four groups. Compared with the blank control group at 24, 32, 40, and 48 hours, the cell proliferation rate decreased significantly after siRNA-HIF-1a transfection, on both two kinds of cultured conditions (P<0.05). The results of plate cloning experiment showed that the number of cell-forming clones increased significantly after hypoxic culture (there were significant differences between the transfected normoxic group and transfected hypoxic group, blank control normoxic group and blank control hypoxic group, P<0.05); and the formation of transfected hypoxic condition group at the same time of hypoxia was also significant (P<0.05). The number of clones were significantly less than that of the blank control group at the hypoxic condition (P<0.05). Transwell lab experiment showed that after hypoxic culture, the number of cells migrated to the inferior chamber in the transfection group was significantly reduced compared with that of the blank control group (P<0.05). Western blot and RT-PCR results showed that the expression levels of HIF-1α protein and tumor stem cell markers (CD133, CD90, and CD44 protein) in the blank control hypoxic condition group were significantly higher than those in the other three groups (P<0.05); after siRNA-HIF-1a transfection, HIF-1α mRNA and tumor stem cell markers mRNA (CD133, CD90, and CD44 mRNA) in the transfected hypoxic condition group were significantly lower than those in the transfected normal condition group and the blank control normal condition group (P<0.05).ConclusionsIn hypoxia environment, HIF-1α can promote hepatocellular carcinoma cells to differentiate into liver cancer stem cells and enhance their malignant biological behavior.