CD98 Activation Increases the Invasion of Human Breast Carcinoma MCF-7 Cells / 체질인류학회지

CD98, a disulfide-linked 125-kDa heterodimeric type II transmembrane glycoprotein, regulates the func-tions of beta1 integrin, suggesting that it may play a role in tumor cell invasion. In this study, the effects of CD98 signaling on the adhesion and invasion of tumor cells were investigated. The expression of CD98 on MCF-7 human breast carcinoma cells was confirmed by immunohistochemistry. The effects of CD98 activation on the adhesion to extracellular matrix (ECM) and invasion of MCF-7 cells were determined by adhesion assay and cell invasion assay. Dominant negative forms of focal adhesion kinase (FAK) were transiently transfected into MCF-7 cells using liposome reagents. CD98 stimulation increased the adhesion of MCF-7 cells to fibronectin, laminin and collagen IV. Activation of CD98 augmented the invasion rate of MCF-7 cells through ECM. EDTA or a function-blocking anti-beta1 integrin mAb suppressed the effect of CD98 on invasiveness. Inhibition of phosphorylation of FAK by PP2, an inhibitor of Src family kinase, reduced CD98-induced invasion of MCF-7 cells. This result was confirmed by over-expression of dominant negative forms of FAK. In addition, cytochalasin D or phalloidin inhibited CD98-mediated induction of tumor cell invasion. Inhibitory effects of PP2, cytochalasin D or phalloidin on CD98-stimulated invasion of MCF-7 cells were diminished by pretreatment of cells with Mn++, which is shown to induce conformational change of beta1 intgerin. These results provide the first evidence that CD98 activation increases tumor cell invasion by activating beta1 integrin affinity, and that FAK phosphorylation and subsequent cytoskeletal reorganization may be essential for CD98-mediated regulation of cell motility.

Tissue Transglutaminase Activates NF-kappaB Pathway in the Atherosclerotic Coronary Artery / 체질인류학회지

Molecular mechanism of nuclear factor-kappaB(NF-kappaB) in the atherosclerosis has been unclear. Recently, NF-kappaB activating function of tissue transglutaminase (tTGase), multifunctional calcium-dependent transamidation enzyme, have been reported in the various tissues like neuroglia. In this report, we investigated the immunoreactivity of tTGase at the human atherosclerotic coronary artery, and examined the effect of tTGase on the well-known proatherogenic NF-kappaB pathway using tTGase-overexpressed cells. Immunohistochemical studies on autopsy samples showed that immunoreactivity of tTGase was markedly elevated in the neointimal tissues of atherosclerotic coronary arteries with progression of disease. Immunohistochemical staining also demonstrated that phosphorylated I-kappaB was activated in the atherosclerotic vessel wall. In vitro study using rat cardiomyoblast (H9c2) and tTGase-overexpressed H9c2 showed that activated tTGase enhanced the phosphorylation of I-kappaB, and this activation was inhibited by tTGase specific inhibitors. These findings suggest that cytosolic tTGase may serve as an activator of NF-kappaB.

Application of Integrative Lecturing to Basic Medicine Courses for Undergraduate Health Allied Sciences Students / 한국의학교육

PURPOSE: In spite of the rapidly expanding importance of the basic sciences, the number of professors teaching basic sciences in medicine has not changed in the last decade. Thus, the need for new methods of teaching and learning has increased. The purpose of this study was to develop and assess integrative lecturing in the basic sciences for undergraduate allied health sciences students. METHODS: We developed an alternate form of lecturing in anatomy, physiology, microbiology, and pathology, focusing on the gastrointestinal system. We tested several teaching strategies including E-learning, face-to-face, and practice. Students majoring in nursing (n=43), sports science (n=26), and emergency medical technology (n=35) participated and were asked to complete an anonymous survey. RESULTS: The majority of the students were satisfied with the new lecture style (86.6%). They preferred integrative lectures to traditional lectures. The degree of satisfaction with E-learning and practice were much higher than with face-to-face. Most of the students identified the knowledge of interdisciplinary relationship and participating in cadaveric dissections as the important effects of this lecture style. CONCLUSION: From this study, it can be suggested that integrative lecturing in basic sciences for public health- / medicine- related courses is effective in teaching and learning. Further studies for the development of integrative contents and system are needed.