Prognostic relationship of metabolic profile obtained of melanoma B16F10

Melanoma is a type of cancer that reaches more people in the world, characterized by genetic mutations that trigger the growth of disorganized cells. The diagnosis of skin tumors by invasive techniques has become a risk to the patients, so the search for new non-invasive techniques has been the subject of research in recent years. The objective of this work is to propose a non-invasive method prognosis based on the identification of specific biomarkers of the cancer, known as metabolomics analysis. For this study, we used B16F10 melanoma tumor cells and metabolic profiles were obtained at three time-periods by ¹H NMR and comparison with the cell cycle, apoptosis pathways and proliferation index. The metabolic profiles show the relationship between the metabolites found with energy metabolism, pathways of apoptosis and proliferation, which showed increases in proportion during growth and progression. Were found 29 metabolites, of which the differentially expressed are: lactate, aspartate, glycerol, lipids, alanine, myo-inositol, phosphocholine, choline, acetate, creatine and taurine. Choline and creatine are closely related with tumor progression, and are inversely expressed in later stages of tumor growth, which demonstrates the ability to be markers of tumor progression or monitoring the pharmacological efficacy when combined with other therapies. We conclude that the metabolome appeared as effective non-invasive technique predicts, besides providing possible biomarkers of melanoma.     

Etoposide loaded solid lipid nanoparticles for curtailing B16F10 melanoma colonization in lung

Poor solubility of etoposide and associated poor bioavailability of the drug was circumvented by developing solid lipid nanocarrier system. The objective of the research work was to prepare etoposide loaded solid lipid nanoparticles (SLN) for improved efficacy and therapy of metastasized cancers. Entrapment of drug into nanoparticulate system modifies the pharmacokinetic and biodistribution profile of the drug with improved therapeutic efficacy. Solid lipid nanoparticles of various triglycerides were prepared using hot homogenization technique. Further, the process and formulation parameters viz. homogenization cycle and pressure, type of lipid were optimized. Developed nanoparticles were characterised for particle size, in vitro dissolution studies, DSC thermogram, surface morphology and cytotoxicity assay. Pharmacokinetic and biodistribution study were performed to assess the distribution of the drug in vivo. Modulation of the therapeutic activity of the drug was studied by performing antimetastatic activity on a B16F10 melanoma mouse model. The obtained results exhibited suitability of trimysristin for fabrication of nanoparticles. Characterisation of nanoparticles depicted formation of homogenous, spherical particles entrapping approximately 50% of the drug. The results for the performed MTT assay suggested that the developed nanoparticles exhibited cytotoxicity in a time- and concentration-dependent fashion. These findings concord with the results of the in vitro dissolution profile. Pharmacokinetic parameters demonstrated increase in area under curve (AUC), t_1/2 and mean residence time (MRT) for drug in plasma. Further there is enhancement in the ratio of the drug that reaches to the highly perfused organs (upon encapsulation into solid lipid nanoparticles). Generally, cancer cells metastasized through the blood or lymphatic system. Accumulation of the drug in the highly perfused organ suggests suitability of the developed nanoparticles for targeting metastasized tumors. This was proved by the findings of the in vivo B16F10 mouse melanoma model. Improvement in the tumoricidal activity and survival rate of the animals substantiates the application of nanoparticles for improved therapeutic activity of etoposide.     

Topoisomerase I inactivation by reticulol and its in vivo cytotoxicity against B16F10 melanoma

To investigate the enzyme-inhibitory efficacy and the cytotoxicity of reticulol produced from a strain of Streptoverticillium, we conducted a DNA topoisomerase (Topo) cleavage assay and an in vivo assay using B16F10 melanoma. From the inhibition assay of reticulol for Topo I, which is involved in melanoma metastasis, it was seen that Topo I treated with 45 microM reticulol did not replicate or transcribe DNA by forming supercoiled DNA. In the annexin V/propidium iodide staining assay to investigate the death pattern of B16F10 cells treated with 200 microM reticulol, proliferation of B16F10 cells was inhibited due to necrosis. Furthermore, from the in vivo assay, reticulol combined with Adriamycin (a mixture with retinolol 5 mg/kg and Adriamycin 1 mg/kg) further retarded the tumor growth compared to that in mice treated with Adriamycin alone (1 mg/kg). The survival rate of tumor-bearing mice treated with the mixture was closely associated with its cytotoxicity. Taken together, these results suggested that reticulol inactivates Topo I, which is involved in tumor metastasis, and exhibits excellent cytotoxic efficacy against B16F10 melanoma, when combined with Adriamycin, in a mouse model.     

Inhibition of melanogenesis in B16-F1 melanoma cells after exposure to diflubenzuron

The insect growth regulator diflubenzuron was found to be a potent inhibitor of melanosome synthesis and release in mouse melanoma cell cultures, and after three to five successive passages of melanoma cells in growth medium containing this compound, these cells were unable to produce monolayers in untreated medium and were incapable of inducing tumor formation in mice. This is the first time that an insect growth regulator has been shown to have a deleterious effect on malignant cells of animals.     

Alteration in the glutathione,glutathione peroxidase,superoxide dismutase and lipid peroxidation by ascorbic acid in the skin of mice exposed to fractionated gamma radiation

BACKGROUND: In spite of the immense therapeutic gains produced by the fractionated irradiation (IR) regimen, radiation burden on the skin increases significantly. Protection of skin might enable use of higher radiation doses for better therapeutic gains. Ascorbic acid (AA), an essential ingredient of the human diet, is known to be a free radical scavenger and radioprotective agent. This study was undertaken to evaluate the effect of ascorbic acid on the radiation-induced changes in the status of glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD) and lipid peroxidation (LPx) in the skin of mice exposed to 10, 16 and 20 Gy of fractionated gamma radiation. METHODS: One group of the animals was administered daily with double distilled water (DDW), while the other group received 250 mg/kg b. wt. of ascorbic acid once daily, consecutively for 5, 8 or 10 days, before hemibody (below rib cage) exposure to 2 Gy/day of gamma-rays. Skin biopsies from both the groups were collected for the biochemical estimations. RESULTS: The irradiation of animals resulted in a dose-dependent decline in the activities of superoxide dismutase, glutathione peroxidase and glutathione contents. Ascorbic acid pretreatment resulted in a significant increase in the activities of both the enzymes and glutathione in the irradiated mouse skin. Normal concentrations of glutathione could not be restored even by day 6 post-irradiation. Conversely, lipid peroxidation increased in a dose-dependent manner in both the groups reaching a peak concentration by 3 h post-irradiation, while the ascorbic acid pretreatment inhibited the radiation-induced increase in lipid peroxidation. CONCLUSIONS: The ascorbic acid treatment arrested the decline in the activities of superoxide dismutase and glutathione peroxidase, glutathione contents and inhibited the radiation-induced lipid peroxidation in the skin of mice exposed to different doses of fractionated gamma radiation.     

Reinforcing B16F10/GPI-IL-21 vaccine efficacy against melanoma by injecting mice with shZEB1 plasmid or miR200c agomir

In this study, we hypothesized that the inhibition of epithelial to mesenchymal transition (EMT) program by knockdown of Zinc-finger E-box binding homeobox 1 (ZEB1) or administration of miR200c agomir would strengthen the B16F10 cells transfected with GPI-anchored IL-21 (B16F10/GPI-IL-21) vaccine efficacy in inhibiting the melanoma metastasis. Our findings from the current study indicated that, when compared with the mice immunized with the B16F10/GPI-IL-21 vaccine alone, the mice immunized with B16F10/GPI-IL-21 vaccine combined with injection of shZEB1 plasmid or miR200c agomir not only meaningfully inhibited EMT of melanoma, reduced the EMT characteristic molecular expression in tumor tissues, but also significantly decreased the Treg cells and TGF-β1, enhanced the cytotoxicities of NK cells and cytotoxic T lymphocytes and the IFN-γ level. Furthermore, the immunotherapeutic combination resulted in inhibiting the melanoma growth and lung metastasis. Our study demonstrated that using the B16F10/GPI-IL-21 vaccine in combination with the down-regulated ZEB1 or miR200c administration effectively elicited anti-tumor immunity and reduced melanoma metastasis by inhibiting the EMT program in the B16F10 melanoma-bearing mice.     

Antitumor efficacy of reticulol from Streptoverticillium against the lung metastasis model B16F10 melanoma. Lung metastasis inhibition by growth inhibition of melanoma

Reticulol was isolated from the culture broth of the strain Streptoverticillium sp. NA-4803. Recticulol (M.W. 222.2) exhibited a potent in vitro cytotoxicity against A427, a human lung tumor cell line, and B16F10, a mouse melanoma cell line. In the trypan blue staining assay for B16F10 cells, the cell viability by reticulol treatment was significantly decreased in a dose-dependent manner. The in vivo assay for the lung metastasis-blocking effect showed that reticulol injected intravenously suppressed the increase in colonies on the lung in a dose-dependent manner. In addition, the survival rate of tumor-implanted mice treated with reticulol was closely associated with its antitumoral efficacy. Reticulol administered via the peritoneum of mice showed less metastasis inhibition than that injected intravenously. To demonstrate the mechanism for inhibition of metastasis, the inhibitory effect of reticulol for matrix metalloproteinase-2 or -9 involved in melanoma metastasis was investigated; however, they were not observed on zymogram gel. In addition, the antitumor efficacy of reticulol was not associated with cell cycle arrest or apoptosis. Therefore, it was inferred that reticulol known as a phosphodiesterase inhibitor directly inhibited the growth of B16F10 melanoma, showing necrotic response. These results suggest that reticulol protects its lung metastasis via the bloodstream by inhibiting the growth of B16F10 melanoma at the cellular level.     

The effect of dietary treatment on erythrocyte lipid peroxidation, superoxide dismutase, glutathione peroxidase, and serum lipid peroxidation in patients with type 2 diabetes mellitus

Objectives: The aim of the present study was to investigate the effect of dietary treatment on serum and erythrocyte lipid peroxidation and erythrocyte antioxidative enzyme activity of patients with Type 2 diabetes.

Design and methods: A total of 30 patients with newly diagnosed as Type 2 diabetes were enrolled to the study. A total of 30 healthy subjects served as controls. Diabetic patients were given standard dietary treatment that was composed of 50% to 55% carbohydrate and 30% fat for 2 months. No diet was applied for controls. For both groups serum and erythrocyte lipid peroxidation and erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were obtained at first and at the end of 2 months.

Results: Diabetic patients had higher serum and erythrocyte lipid peroxidation than those of controls before dietary treatment(p < 0.05). However, there was no absolute differences in erythrocyte SOD and GSH-Px (p > 0.05). At the end of 2 months of dietary treatment, while diabetics had still higher glucose and erythrocyte lipid peroxidation than controls (p < 0.05), serum lipid peroxidation, erythrocyte SOD, and GSH-Px levels did not differ significantly from those of controls (p > 0.05). In diabetic patients, after 2 months of dietary treatment, whereas serum and erythrocyte lipid peroxidation decreased, erythrocyte SOD and GSH-Px activities showed significant increase (p < 0.05).

Conclusions: Our results showed significant alteration in serum and erythrocyte lipid peroxidation and erythrocyte antioxidant enzyme status of patients with Type 2 diabetes by dietary treatment. However, whether such alterations have clinical importance for diabetic patients needs further investigation.     

Novel membrane-bound GM-CSF vaccines for the treatment of cancer: generation and evaluation of mbGM-CSF mouse B16F10 melanoma cell vaccine

Cancer vaccines composed of tumor cells engineered to secrete granulocyte-macrophage colony-stimulating factor (GM-CSF) are currently being clinically evaluated. To enhance the immunogenicity of GM-CSF-secreting tumor cell vaccines, a novel approach expressing GM-CSF as a membrane-bound form (mbGM-CSF) on the tumor cell surface was investigated. The intent was to enhance antigen presentation by increasing interactions between the tumor cell lines in the vaccine and GM-CSF receptor positive antigen presenting cells (APC), notably the patient's Langerhans cells residing within the intradermal injection site. B16.F10 cells engineered to express either membrane-bound or secreted GM-CSF were compared in the B16.F10 mouse melanoma model. We observed that mbGM-CSF on the tumor cell surface retarded growth and induced protective immunity to subsequent wild-type tumor challenge more effectively than tumor cells secreting GM-CSF. Vaccination with irradiated mbGM-CSF B16.F10 also provided strong protection from wild-type tumor challenge, improved therapeutic effects against established tumors, and retarded lung metastases. These results demonstrate that mbGM-CSF B16.F10 cells can induce strong systemic immunity that protects against and therapeutically treats B16.F10 melanoma more effectively than analogous vaccines containing only secreted GM-CSF. These data warrant further development and clinical testing of mbGM-CSF tumor cell vaccines.     

Comparison of the endocytic properties of linear and branched PEIs, and cationic PAMAM dendrimers in B16f10 melanoma cells.

Many different polymers and architectures are now being developed as polymer therapeutics and non-viral vectors for cytosolic delivery, and cationic dendrimers, and linear and branched poly(ethylenimine)s (PEIs) have been widely used. For rational design and safe transfer into the clinic, it is important to better understand the cellular pharmacokinetics of the carrier, even if this will likely change when it is conjugated to, or complexed with, a targeting residue or therapeutic payload. The aim of these studies was to compare binding, endocytic capture and intracellular trafficking of linear and branched PEIs (Mw 25,000 g/mol) and cationic PAMAM dendrimers (generations (gen) 2- 4) using B16F10 murine melanoma cells. FITC-dextran was used as a control for comparison. All polymers were first conjugated to Oregon Green (OG) and carefully characterised in respect of pH- and concentration-dependence of fluorescence. Throughout, non-toxic concentrations of polymer were used. Flow cytometry showed that all the cationic polymers were internalised by "adsorptive" endocytosis, with maximum uptake seen for PAMAM gen 4>branched PEI>linear PEI>PAMAM gen 3>PAMAM gen 2. The PAMAM gen 4 uptake rate was 130 fold greater than seen for FITC-dextran. Branched PEI had the highest extracellular binding (accounting for >50% of total cell-associated fluorescence) whereas for the linear PEI, binding was only 13% of the cell-associated fluorescence. Unlike FITC-dextran, all cationic polymers lacked significant exocytosis over the time period studied. Whereas PAMAM gen 4 and the branched PEI were predominately internalised by cholesterol-dependent pathways, internalisation of linear PEI appeared to be independent of clathrin and cholesterol. A perception of the rate and mechanisms of cellular uptake of these vectors will be important in the context of their proposed use as drug delivery systems.     

Effect of endothelin-1 on intracellular glutathione and lipid peroxide availability and on the secretion of vasoactive substances by human umbilical vein endothelial cells

BACKGROUND: The major pathophysiologic changes observed in preeclampsia suggest that endothelial cell dysfunction plays an important role in this disorder. The pathway mediating endothelial cell layer dysfunction is unknown. The concentration of endothelin-1 (ET-1), a potent mammalian vasoconstrictor peptide produced by the vascular endothelium, has been observed to be significantly increased in preeclampsia. In this study, we determined the in vitro effect of endothelin-1 on glutathione and lipid peroxide levels and on the secretion of vasoactive substances by human umbilical vein endothelial cells (HUVECs). METHODS: Human umbilical vein endothelial cells were incubated for 24 h in the presence of different concentrations of ET-1 (0-1000 pmol L(-1)), which were shown in an earlier experiment to have no effects on vitality and proliferation rate of HUVECs. The levels of glutathione (GSH) and lipid peroxides (LPO) were measured in endothelial cell lysates. For the measurement of vasoactive substances, levels of nitric oxide (NO), prostacyclin (PGI2) and thromboxane A2 (TXA2) were measured in endothelial cell supernatants. RESULTS: At lower concentrations (5-50 pmol L(-1)), ET-1 increases the intracellular content of LPO, stimulates the secretion of TXA2, but inhibits the secretion of PGI2 in endothelial cells compared with control cells. At higher concentrations (100-1000 pmol L(-1)), ET-1 increases the intracellular content of GSH, but results in a decrease of LPO, and increase of PGI2, back to control levels. ET-1 has no effect on NO secretion. CONCLUSION: These findings demonstrate that at concentrations corresponding to values in plasma from preeclamptic women, ET-1 induces oxidative stress and results in altered secretion of vasoactive substances in human endothelial cells. We conclude that ET-1 may participate in the pathway leading to endothelial cell dysfunction seen in preeclampsia.     

Prevention of hippocampus neuronal damage in ischemic gerbils by a novel lipid peroxidation inhibitor (quinazoline derivative)

We investigated the effect of a novel quinazoline derivative (KB-5666), a lipid peroxidation inhibitor, on ischemic neuronal damage using Mongolian gerbils. The animals were sacrificed 7 or 30 days after 5 min of forebrain ischemia induced by bilateral common carotid artery occlusion. Morphologic changes, a microtubule-associated protein 2 (MAP2) immunohistochemical study and quantitative autoradiographic study using [3H]phorbol 12, 13-dibutyrate ([3H]PDBu) were evaluated in the hippocampus after ischemia. KB-5666 (3-50 mg/kg, i.v.) showed protective effects against neuronal death of the CA1 subfield 5 min before ischemia, immediately or 1 hr after ischemia, but not 4 hr after ischemia. KB-5666 (i.p.) also showed protective effects in a dose-dependent manner immediately after ischemia. Furthermore, KB-5666 dose-dependently prevented a marked decrease in microtubule-associated protein 2 immunoreactivity in the dendritic fields of the CA1 pyramidal cells after ischemia. The [3H]PDBu binding activity in the stratum oriens and the stratum lacunosum-moleculare of the CA1 subfield was reduced by 19 and 30%, respectively, 7 days after ischemia. [3H]PDBu binding sites were unchanged in the stratum oriens in the CA3 subfield. By contrast, in the molecular layer of the dentate gyrus, the [3H]PDBu binding activity increased by 15%. KB-5666 (i.v.) prevented a decrease in the [3H]PDBu binding activity in the stratum oriens and stratum lacunosum-moleculare of the CA1 subfield and an increase in the molecular layer of the dentate gyrus. These histologic, immunohistochemical and receptor-autoradiographic data indicate that KB-5666 protects the brain from both cellular and functional consequences of ischemia.     

Lansoprazole inhibits mitochondrial superoxide production and cellular lipid peroxidation induced by indomethacin in RGM1 cells

Lansoprazole is effective in healing non-steroidal anti-inflammatory drugs induced ulcers, and antioxidant properties have been thought to play a key role in healing ulcers. We hypothesize that lansoprazole exerts a cytoprotective effect by inhibiting reactive oxygen species leakage from mitochondria and lipid peroxidation. We pretreated gastric epithelial RGM1 cells with lansoprazole and then treated them with indomethacin in vitro. We found that the lansoprazole pretreatment significantly reduced cellular injury, maintained mitochondrial transmembrane potential, and decreased lipid peroxidation. Furthermore, the signal intensity of the electron spin resonance spectrum of the indomethacin-treated mitochondria which were pretreated with lansoprazole showed considerable reduction compared to those without the lansoprazole pretreatment. These results suggest that lansoprazole reduced superoxide production in the mitochondria of indomethacin treated cells, and subsequently inhibited lipid peroxide and cellular injury in gastric epithelial cells.     

Functional roles of hyaluronan in B16-F10 melanoma growth and experimental metastasis in mice

Although hyaluronan (HA), a high molecular weight glycosaminoglycan, is generally believed to regulate tumor growth, invasion, and metastasis, functional roles of HA have only been speculated indirectly from the outcome of blocking HA receptors (e.g., CD44). Using a phage display technique, we recently developed a synthetic peptide (GAHWQFNALTVR; Pep-1) that binds to and inhibits the function of HA. In this study, we have used Pep-1 to determine whether HA directly regulates the behavior of tumor cells. B16-F10 melanoma cells, which constitutively expressed CD44, showed significant adhesion to HA-coated plates, and this adhesion was blocked almost completely either by neutralizing antibodies against CD44 or by Pep-1. These results imply that CD44 is the primary HA receptor mediating the adhesive interaction of the melanoma cells with HA substrates. In contrast, Pep-1 failed to inhibit in vitro proliferation of B16-F10 melanoma cells or the in vitro growth of the cells after s.c. inoculation in mice. Importantly, single injection of Pep-1 significantly reduced the incidence of lung metastasis of i.v. inoculated melanoma cells and prolonged the survival of the tumor-bearing animals. These results suggest a direct contribution of HA to one or more steps in the initial seeding of melanoma cells in the lung microenvironment. Our observations also introduce a new concept that synthetic inhibitors of HA may represent unique tools for studying the roles of HA in tumor biology and perhaps a new class of therapeutic reagents.     

Direct visualization of changes of lymphatic function and drainage pathways in lymph node metastasis of B16F10 melanoma using near-infrared fluorescence imaging

The lymphatic system provides an initial route for cancer cell dissemination in many cancers including melanoma. However, it is largely unknown how the lymphatic system changes during tumor progression due in part to the lack of imaging techniques currently available. In this study, we non-invasively imaged changes of lymphatic function and drainage patterns using near-infrared fluorescence (NIRF) imaging. Dynamic NIRF imaging following intradermal injection of indocyanine green (ICG) was conducted in C57BL/6 mice prior to inoculation of B16F10 murine melanoma cells to the dorsal aspect of the left hindpaw for baseline data or directly to the popliteal lymph node (PLN) and until 21 days post-implantation (p.i.). A series of acquired fluorescent images were quantified to measure lymphatic contractile function. Computed tomography (CT) was also performed to measure the volume of tumor-draining lymph nodes (LNs). We observed significant reduction of lymphatic contractility from 7 days p.i. until 21 days p.i.. Altered lymphatic drainage patterns were also detected at 21 days p.i. in mice with tumor in the paw and at 11 days p.i. in mice with tumor in the PLN, due to lymphatic obstruction of normal lymphatic drainages caused by extensive tumor invasion of draining LNs. Since lymphatic function and architecture were progressively altered during tumor growth and metastasis, non-invasive NIRF imaging may provide a new method to stage disease. In addition, this novel technique can be used as a diagnostic method to non-invasively assess lymphatic response as mechanism of therapeutic action.OCIS codes: (170.0170) Medical optics and biotechnology, (170.2655) Functional monitoring and imaging, (170.3880) Medical and biological imaging, (170.4580) Optical diagnostics for medicine     

8-Isoprostaglandin F2 alpha: a potential index of lipid peroxidation in systemic lupus erythematosus

BACKGROUND: Lipid peroxidation is a central feature of oxidant injury that leads to the vascular disease associated with systemic lupus erythematosus (SLE). In the past, lipid peroxidation has been difficult to measure. Because isoprostanes are thought to have particular relevance in vascular disease, we set out to measure, in vivo, serum concentrations of 8-isoprostaglandin F2 alpha (8-iso-PGF2alpha) as a marker of oxidative stress to evaluate the occurrence and ascertain the significance of lipid peroxidation in SLE. METHODS: Sixty patients with SLE and 20 age- and sex-matched controls were recruited. Patients were assessed according to a standard protocol, including demographic, clinical, laboratory and treatment variables. We measured the serum concentrations of 8-iso-PGF2alpha using the enzyme-linked immunoabsorbent assay. Fasting lipid profiles and serum lipid peroxide concentrations were also assessed in both SLE patients and controls. RESULTS: In SLE patients, with a mean age of 22.4 (standard deviation [SD] 2.7) years and a disease duration of 20.9 (SD 4.9) months, the serum concentrations of 8-iso-PGF2alpha were higher than in the age- and sex-matched controls (p < 0.001). The mean level of 8-iso-PGF2alpha in SLE patients was 466 (SD 296.8) pg/mL compared with a mean of 90.9 (SD 26.6) pg/mL in the control group (p < 0.001). Our findings revealed a dose-response relationship between 8-iso-PGF2alpha concentrations and the dosage of prednisone. The level of serum lipid peroxide in SLE patients was increased compared with levels measured in the control group. CONCLUSIONS: Our findings suggest that oxidative stress is implicated in the pathogenesis of SLE and that 8-iso-PGF2alpha can be used as a sensitive, noninvasive, reliable marker of oxidative stress in vivo. Furthermore, it should be possible to target therapies more effectively so that the detrimental actions of vascular oxygen free radicals can be reduced.     

蛋白酶活化受体1在B16F10瘤细胞体内外迁移中的作用

目的:研究蛋白酶活化受体 1(PAR1)在肿瘤细胞转移过程中的作用,评估凝血系统与肿瘤转移的关系。方法:首先通过逆转录聚合酶链反应(RT-PCR)和 Western-blot 方法检测了 siRNA 对 B16F10 黑色素瘤细胞中 PAR1的内源表达的影响,然后在 PAR1 受 siRNA 干扰的情况下检测 B16F10细胞在体内外迁移能力,其结果与未受siRNA 干扰的试验结果相对照,来确定 PAR1 在 B16F10 瘤细胞体内外迁移中的作用。结果:75nmol/L 的 siRNA 干扰48h 后可明显抑制 B16F10中 PAR1 的表达,其转录水平抑制率是60%,蛋白水平的抑制率为85%;体外迁移实验表明,PAR1 表达量减少后与对照组相比细胞迁移能力减弱(P<0.01);动物实验表明.干扰 B16F10细胞中的 PAR1后,肿瘤细胞经血管迁移能力减弱,在肺部形成的转移瘤数目减少(P<0.01)。结论:PAR1 具有促进肿瘤细胞迁移作用。开发 PAR1 封闭剂有望抑制肿瘤转移,可作为研制抗肿瘤转移药物的新靶点。