Résumé
PURPOSE: The insulin-like growth factor II (IGF-II) gene expresses a family of transcripts in embryonic/fetal tissue, and also highly was expressed during hepatocellular carcinogenesis. In this study, we showed that IGF-II mRNA and protein levels are detected in rat embryo, HepG2 human hepatoma cells and Chang liver cells. MATERIALS AND METHODS: This study included sections of rat embryos 7~17 days post coitum (d.p.c), HepG2 cells and Chang liver cells. Using immunohistochemistry, Northern blotting and Western blotting, we observed the expression of IGF-II in the rat embryo, HepG2 cells and Chang liver cells. RESULTS: We localized IGF-II gene products in sections of rat embryo 7~17 d.p.c by performing immunohistochemistry. The IGF-II was mainly expressed in the proximal endoderm and ectoplacental cone between 7 and 9 d.p.c. At 10 d.p.c. the expression was localized at the heart primodium as well as the proximal endoderm, and at 11 d.p.c. the IGF-II was expressed in the liver and heart. After 12 d.p.c. and 14 d.p.c., the expression was also detected in the brain, muscle and bone, and head mesenchyme, respectively. While the expression of IGF-II protein was not detected in the normal adult liver, intense staining was detected in the heart, liver and choroids plexus at 17 d.p.c. CONCLUSION: These results suggest that IGF-II may act as an oncofetal protein during hepatocellular carcinogenesis and embryogenesis.
Sujets)
Adulte , Animaux , Femelle , Humains , Grossesse , Rats , Technique de Northern , Technique de Western , Encéphale , Carcinogenèse , Carcinome hépatocellulaire , Choroïde , Développement embryonnaire , Structures de l'embryon , Endoderme , Tête , Coeur , Cellules HepG2 , Immunohistochimie , Facteur de croissance IGF-II , Foie , Mésoderme , ARN messagerRésumé
PURPOSE: Hepatocellular carcinoma (HCC), a typical hypervasculized tumor is very sensitive to hypoxia and vascular endothelial growth factor (VEGF) has previously been identified to be up-regulated in response to hypoxia in several cell types. However, the molecular mechanisms by which hypoxia is sensed by the cells remain enigmatic. To investigate whether calcium and AP-1 are involved in hypoxia-sensing mechanism, we performed following experiments. MATERIALS AND METHODS: Hep3B cells were grown in hypoxic condition. To assess cell viability, MTT assay was performed. To investigate the effect of calcium and AP-1, northern blot analysis was performed after treatment with BAPTA/AM. RESULTS: The expression of VEGF was significantly up-regulated by hypoxia in Hep3B, hepatocellular carcinoma cell line. The increased expression of VEGF induced by hypoxia was blocked by the addition of BAPTA/AM, a cytosolic calcium chelator to the media. In addition, we found that the expression of c-jun protooncogene was also up-regulated by hypoxia. Hypoxic increase of c-jun expression was also normalized by the treatment with BAPTA/AM. CONCLUSION: These results suggest that the increased expression of VEGF by hypoxia is mediated through the calcium and c-jun signalling pathway in the Hep3B human hepatoma cell lines.
Sujets)
Humains , Hypoxie , Technique de Northern , Calcium , Carcinome hépatocellulaire , Lignée cellulaire , Survie cellulaire , Cytosol , Facteur de transcription AP-1 , Facteur de croissance endothéliale vasculaire de type ARésumé
The common bile duct and the duct of Wirsung cojoin at the level of the duodenum, forming the major. papilla of Vater. Existence of a double major papilla, i.e., two neighboring independent papillary structure:, is infrequent. In our endoscopy unit we have experienced one case of double papilla of Vater wherein canulation of the common bile duct and pancreatic duct could be accom plished through either orifice independently.
Sujets)
Conduit cholédoque , Duodénum , Endoscopie , Conduits pancréatiquesRésumé
C-fos protein is a gene regulatory third messenger involved in long-term responses of cells to various stimuli. Kainic acid(KA), a powerful excitatory analogue, induces seizures and damages the hippocampus and other limbic regions in rats. KA treatment induces c-fos protein production in the hippocampus. This study was undertaken to investigate the expression of c-fos protein in the hippocampus according to seizure stage induced by systemic injection of KA. Twenty-three adult male Sprague-Dawley rats experienced convulsions by a single intraperitoneal injection of convulsive dose (20-40 mg/Kg) of KA. Seven control rats received normal saline. Animals were sacrificed 3 hr after KA treatment. The expression of c-fos protein was tested in the hippocampus by immunohistochemical staining using polyclonal anti-Fos. Most of the rats exhibited limbic motor epileptic activity. C-fos protein immunoreactivity increased in the CA1, CA3 and dentate gyrus at stage 1-2, and not only in the CA1, CA3 and dentate gyrus but also in the CA4 at stage 3-4. At stage 5, c-fos protein immunoreactivity increased in all areas of the hippocampus. C-fos protein immunoreactivity increased progressively with increasing severity of convulsions. These results show that KA produces limbic motor seizure associated with a rise in the c-fos protein in the hippocampus, and that the expression of c-fos protein may has some relevance to the progressive and permanent brain changes occurring during epilepsy.
Sujets)
Adulte , Animaux , Humains , Mâle , Rats , Encéphale , Gyrus denté , Épilepsie , Gènes vif , Hippocampe , Injections péritoneales , Rat Sprague-Dawley , Crises épileptiquesRésumé
No abstract available.
Résumé
No abstract available.