Cell migration is essential to direct embryonic cells to specific sites at which their developmental fates are ultimately determined. However, the mechanism by which cell motility is regulated in embryonic development...Cell migration is essential to direct embryonic cells to specific sites at which their developmental fates are ultimately determined. However, the mechanism by which cell motility is regulated in embryonic development is largely unknown. Cortactin, a filamentous actin binding protein, is an activator of Arp2/3 complex in the nucleation of actin cytoskeleton at the cell leading edge and acts directly on the machinery of cell motility. To determine whether cortactin and Arp2/3 mediated actin assembly plays a role in the morphogenic cell movements during the early development of zebrafish, we initiated a study of cortactin expression in zebrafish embryos at gastrulating stages when massive cell migrations occur. Western blot analysis using a cortactin specific monoclonal antibody demonstrated that cortactin protein is abundantly present in em-bryos at the most early developmental stages. Immunostaining of whole-mounted embryo showed that cortactin immunoreactivity was associated with the embryonic shield, predominantly at the dorsal side of the embryos during gastrulation. In addition, cortactin was detected in the convergent cells of the epiblast and hypoblast, and later in the central nervous system. Im-munofluorescent staining with cortactin and Arp3 antibodies also revealed that cortactin and Arp2/3 complex colocalized at the periphery and many patches associated with the cell-to-cell junction in motile embryonic cells. Therefore, our data suggest that cortactin and Arp2/3 medi-ated actin polymerization is implicated in the cell movement during gastrulation and perhaps the development of the central neural system as well.展开更多
Cell phone and personal computer use has increased considerably in recent years, particularly in developed countries. These devices have facilitated communication on a global scale. However, there have been a number o...Cell phone and personal computer use has increased considerably in recent years, particularly in developed countries. These devices have facilitated communication on a global scale. However, there have been a number of reports of health problems related to the electromagnetic waves emitted by such electronic devices. A long list of both general and severe symptoms, including headaches, fatigue, tinnitus, dizziness, memory loss, irregular heartbeat and whole-body skin le-sions, have been reported. These are reportedly associated with the condition known as electro-magnetic hypersensitivity (EHS). This report shows how a subject’s abnormal involuntary body movements, caused by electromagnetic waves emitted by a cell phone, are prevented by placing a gold alloy inlay in the subject’s mouth. It appears that the subject’s involuntary movements are the result of balance dysregulation resulting from EHS. The subject’s various symptoms improve after the specific dental treatment. However, the underlying mechanism of the symptoms and the rea-sons why this treatment is so successful remain unknown. Further research is required to clarify these issues.展开更多
AIM: To demonstrate the relationship between H-ras oncogene and hepatocellular carcinoma (HCC) metastasis. METHODS: Activated H-ras oncogene was transfected into SMMC 7721, a cell line derived from human HCC, by calci...AIM: To demonstrate the relationship between H-ras oncogene and hepatocellular carcinoma (HCC) metastasis. METHODS: Activated H-ras oncogene was transfected into SMMC 7721, a cell line derived from human HCC, by calcium phosphate transfection method. Some metastasis-related parameters were detected in vitro, including adhesion assay, migration assay, expression of collagenase IV(c IV ase) and epidermal growth factor receptor (EGFR). RESULTS: The abilities of H-ras-transfected cell clones in adhesion to laminin (LN) or fibronectin (FN), migration, c IV ase secretion increased markedly, and the expression of EGFR elevated moderately. More importantly, these alterations were consistent positively with the expression of p21, the protein product of H-ras oncogene. CONCLUSION: H-ras oncogene could induce the metastatic phenotype of HCC cell in vitro to raise its metastatic potential.展开更多
AIML To investigate the effect and mechanism of action of the nitric oxide synthase （NOS） inhibitor NG-nitro-L-arginine methyl ester （L-NAME） on invasion and metastasis of human colorectal cancer cell line SL-174T...AIML To investigate the effect and mechanism of action of the nitric oxide synthase （NOS） inhibitor NG-nitro-L-arginine methyl ester （L-NAME） on invasion and metastasis of human colorectal cancer cell line SL-174T. METHODS： Human colorectal cancer cel4 line SL-174T was cultured and treated separately with four different dosages of L-NAME for 72 h, Nitric oxide （NO） production was measured with Griess reagent, The effect of L-NAME on invasion and migration of SL-174T cells were evaluated by using Transwell chambers attached with polycarbonate filters and reconstituted basement membrane （Matrigel）, RT-PCR was performed to determine the mRNA levels of matrix metalloproteinase-2 （MMP-2） and tissue inhibitor metalloproteinase-2 （TIMP-2）,RESULTS： L-NAME could significantly inhibit NO production of SL-174T in a dose-dependent manner. After being treated for 72 h with 0.2, 0.4, 0.8, and 1.0 mmol/L L- NAME, respectively, the ability of the L-NAME treated SL- 174T cells to invade the reconstituted basement membrane decreased significantly （t = 8.056, P〈0.05; t= 14.467, P〈0.01; t= 27.785, P〈0.01; and t= 29.405, P〈0.01, respectively） and the inhibition rates were 10.29%, 19.62%, 34.08%, and 42.23%, respectively. Moreover, L-NAME could inhibit migration of SL-174T cells, and the inhibition rates were 20.76%, 24.95%, 39.43%, and 46. 85% for L-NAME at 0.2, 0.4, 0.8, and 1.0 mmol/L, respectively （t = 15.116, P〈0.01）. In addition, after treatment with L-NAME, expression of MMP-2 mRNA was significantly decreased （t = 71.238, P〈0.01） and that of TIMP-2 mRNA was markedly increased （t = -13.020, P〈0.01）. CONCLUSION： L-NAME exerts anti-invasive and anti- metastatic effects on SL-174T cell line via downregulating MNP-2 mRNA expression and upregulating TIMP-2 mRNA expression.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.30270692&30271034).
文摘Cell migration is essential to direct embryonic cells to specific sites at which their developmental fates are ultimately determined. However, the mechanism by which cell motility is regulated in embryonic development is largely unknown. Cortactin, a filamentous actin binding protein, is an activator of Arp2/3 complex in the nucleation of actin cytoskeleton at the cell leading edge and acts directly on the machinery of cell motility. To determine whether cortactin and Arp2/3 mediated actin assembly plays a role in the morphogenic cell movements during the early development of zebrafish, we initiated a study of cortactin expression in zebrafish embryos at gastrulating stages when massive cell migrations occur. Western blot analysis using a cortactin specific monoclonal antibody demonstrated that cortactin protein is abundantly present in em-bryos at the most early developmental stages. Immunostaining of whole-mounted embryo showed that cortactin immunoreactivity was associated with the embryonic shield, predominantly at the dorsal side of the embryos during gastrulation. In addition, cortactin was detected in the convergent cells of the epiblast and hypoblast, and later in the central nervous system. Im-munofluorescent staining with cortactin and Arp3 antibodies also revealed that cortactin and Arp2/3 complex colocalized at the periphery and many patches associated with the cell-to-cell junction in motile embryonic cells. Therefore, our data suggest that cortactin and Arp2/3 medi-ated actin polymerization is implicated in the cell movement during gastrulation and perhaps the development of the central neural system as well.
文摘Cell phone and personal computer use has increased considerably in recent years, particularly in developed countries. These devices have facilitated communication on a global scale. However, there have been a number of reports of health problems related to the electromagnetic waves emitted by such electronic devices. A long list of both general and severe symptoms, including headaches, fatigue, tinnitus, dizziness, memory loss, irregular heartbeat and whole-body skin le-sions, have been reported. These are reportedly associated with the condition known as electro-magnetic hypersensitivity (EHS). This report shows how a subject’s abnormal involuntary body movements, caused by electromagnetic waves emitted by a cell phone, are prevented by placing a gold alloy inlay in the subject’s mouth. It appears that the subject’s involuntary movements are the result of balance dysregulation resulting from EHS. The subject’s various symptoms improve after the specific dental treatment. However, the underlying mechanism of the symptoms and the rea-sons why this treatment is so successful remain unknown. Further research is required to clarify these issues.
文摘AIM: To demonstrate the relationship between H-ras oncogene and hepatocellular carcinoma (HCC) metastasis. METHODS: Activated H-ras oncogene was transfected into SMMC 7721, a cell line derived from human HCC, by calcium phosphate transfection method. Some metastasis-related parameters were detected in vitro, including adhesion assay, migration assay, expression of collagenase IV(c IV ase) and epidermal growth factor receptor (EGFR). RESULTS: The abilities of H-ras-transfected cell clones in adhesion to laminin (LN) or fibronectin (FN), migration, c IV ase secretion increased markedly, and the expression of EGFR elevated moderately. More importantly, these alterations were consistent positively with the expression of p21, the protein product of H-ras oncogene. CONCLUSION: H-ras oncogene could induce the metastatic phenotype of HCC cell in vitro to raise its metastatic potential.
文摘AIML To investigate the effect and mechanism of action of the nitric oxide synthase （NOS） inhibitor NG-nitro-L-arginine methyl ester （L-NAME） on invasion and metastasis of human colorectal cancer cell line SL-174T. METHODS： Human colorectal cancer cel4 line SL-174T was cultured and treated separately with four different dosages of L-NAME for 72 h, Nitric oxide （NO） production was measured with Griess reagent, The effect of L-NAME on invasion and migration of SL-174T cells were evaluated by using Transwell chambers attached with polycarbonate filters and reconstituted basement membrane （Matrigel）, RT-PCR was performed to determine the mRNA levels of matrix metalloproteinase-2 （MMP-2） and tissue inhibitor metalloproteinase-2 （TIMP-2）,RESULTS： L-NAME could significantly inhibit NO production of SL-174T in a dose-dependent manner. After being treated for 72 h with 0.2, 0.4, 0.8, and 1.0 mmol/L L- NAME, respectively, the ability of the L-NAME treated SL- 174T cells to invade the reconstituted basement membrane decreased significantly （t = 8.056, P〈0.05; t= 14.467, P〈0.01; t= 27.785, P〈0.01; and t= 29.405, P〈0.01, respectively） and the inhibition rates were 10.29%, 19.62%, 34.08%, and 42.23%, respectively. Moreover, L-NAME could inhibit migration of SL-174T cells, and the inhibition rates were 20.76%, 24.95%, 39.43%, and 46. 85% for L-NAME at 0.2, 0.4, 0.8, and 1.0 mmol/L, respectively （t = 15.116, P〈0.01）. In addition, after treatment with L-NAME, expression of MMP-2 mRNA was significantly decreased （t = 71.238, P〈0.01） and that of TIMP-2 mRNA was markedly increased （t = -13.020, P〈0.01）. CONCLUSION： L-NAME exerts anti-invasive and anti- metastatic effects on SL-174T cell line via downregulating MNP-2 mRNA expression and upregulating TIMP-2 mRNA expression.
