Genetic heterogeneity of liver cancer stem cells / 대한해부학회지

Cancer cell heterogeneity is a serious problem in the control of tumor progression because it can cause chemoresistance and metastasis. Heterogeneity can be generated by various mechanisms, including genetic evolution of cancer cells, cancer stem cells (CSCs), and niche heterogeneity. Because the genetic heterogeneity of CSCs has been poorly characterized, the genetic mutation status of CSCs was examined using Exome-Seq and RNA-Seq data of liver cancer.Here we show that different surface markers for liver cancer stem cells (LCSCs) showed a unique propensity for genetic mutations. Cluster of differentiation 133 (CD133)-positive cells showed frequent mutations in the IRF2, BAP1, and ERBB3 genes. However, leucine-rich repeat-containing G protein-coupled receptor 5-positive cells showed frequent mutations in the CTNNB1, RELN, and ROBO1 genes. In addition, some genetic mutations were frequently observed irrespective of the surface markers for LCSCs. BAP1 mutations was frequently observed in CD133-, CD24-, CD13-, CD90-, epithelial cell adhesion molecule-, or keratin 19-positive LCSCs. ASXL2, ERBB3, IRF2, TLX3, CPS1, and NFATC2 mutations were observed in more than three types of LCSCs, suggesting that common mechanisms for the development of these LCSCs. The present study provides genetic heterogeneity depending on the surface markers for LCSCs. The genetic heterogeneity of LCSCs should be considered in the development of LCSC-targeting therapeutics.

Large-scale functional brain networks for consciousness / 대한해부학회지

The generation and maintenance of consciousness are fundamental but difficult subjects in the fields of psychology, philosophy, neuroscience, and medicine. However, recent developments in neuro-imaging techniques coupled with network analysis have greatly advanced our understanding of consciousness. The present review focuses on large-scale functional brain networks based on neuro-imaging data to explain the awareness (contents) and wakefulness of consciousness.Despite limitations, neuroimaging data suggests brain maps for important psychological and cognitive processes such as attention, language, self-referential, emotion, motivation, social behavior, and wakefulness. We considered a review of these advancements would provide new insights into research on the neural correlates of consciousness.

Large-scale functional brain networks for consciousness / 대한해부학회지

The generation and maintenance of consciousness are fundamental but difficult subjects in the fields of psychology, philosophy, neuroscience, and medicine. However, recent developments in neuro-imaging techniques coupled with network analysis have greatly advanced our understanding of consciousness. The present review focuses on large-scale functional brain networks based on neuro-imaging data to explain the awareness (contents) and wakefulness of consciousness.Despite limitations, neuroimaging data suggests brain maps for important psychological and cognitive processes such as attention, language, self-referential, emotion, motivation, social behavior, and wakefulness. We considered a review of these advancements would provide new insights into research on the neural correlates of consciousness.

Development and Validation of a Risk Scoring System Derived from Meta-Analyses of Papillary Thyroid Cancer

Background@#The aim of this study was to develop a scoring system to stratify the risk of papillary thyroid cancer (PTC) and to select the proper management. @*Methods@#We performed a systematic search of MEDLINE and Embase. Data regarding patients’ prognoses were obtained from the included studies. Odds ratios (ORs) with statistical significance were extracted from the publications. To generate a risk scoring system (RSS), ORs were summed (RSS1), and summed after natural-logarithmic transformation (RSS2). RSS1 and RSS2 were compared to the eighth edition of the American Joint Committee on Cancer (AJCC) staging system and the 2015 American Thyroid Association (ATA) guidelines for thyroid nodules and differentiated thyroid carcinoma. @*Results@#Five meta-analyses were eligible for inclusion in the study. Eight variables (sex, tumour size, extrathyroidal extension, BRAF mutation, TERT mutation, histologic subtype, lymph node metastasis, and distant metastasis) were included. RSS1 was the best of the analysed models. @*Conclusion@#We developed and validated a new RSS derived from previous meta-analyses for patients with PTC. This RSS seems to be superior to previously published systems.

Prognostic Value of MicroRNAs in Coronary Artery Diseases: A Meta-Analysis

PURPOSE: Coronary artery diseases (CADs) are the leading causes of death in the world. Recent studies have reported that differentially expressed microRNAs (miRNAs) are associated with prognosis or major adverse cardiac events (MACEs) in CAD patients. In a previous meta-analysis, the authors made serious mistakes that we aimed to correct through an updated systematic review and meta-analysis of the prognostic value of altered miRNAs in patients with CADs. MATERIALS AND METHODS: We performed a systematic search of MEDLINE (from inception to May 2017) and EMBASE (from inception to May 2017) for English-language publications. Studies of CADs with results on miRNAs that reported survival data or MACEs were included. Data were extracted from each publication independently by two reviewers. RESULTS: After reviewing 515 articles, a total eight studies were included in this study. We measured pooled hazard ratios (HRs) and 95% confidence intervals (CIs) of miRNA 133a with a fixed-effect model (pooled HR, 2.35; 95% CI, 1.56–3.55). High expression of miRNA 133a, 208b, 126, 197, 223, and 122-5p were associated with high mortality. Additionally, high levels of miRNA 208b, 499-5p, 134, 328, and 34a were related with MACEs. CONCLUSION: The present study confirmed that miRNA 133a, which was associated with high mortality in CAD patients, holds prognostic value in CAD. More importantly, this study corrected issues raised against a prior meta-analysis and provides accurate information.

The Impact of Alternating Dissection in Conjunction with Reciprocal Peer Teaching on Practical Exam Scores in a Medical Anatomy Course / 체질인류학회지

The reformation of medical curriculum induced the reduction of anatomy course schedule especially in contact hours in anatomy laboratory. It has led to the use of more efficient teaching approaches in anatomy laboratory. The purpose of this work provide a detailed analysis of alternating dissections with reciprocal peer teaching in anatomy laboratory. Students were assigned alphabetically, in teams of eight or nine, to each dissecting table. The team was subdivided into two groups, A and B, each group dissected every other session. Students excused from dissection spent their time with team-based learning and self-directed learning. Dissected peer-teaching groups presented structures from the dissection to groups absent during dissection. Practical exam scores of the alternating dissection indicated no significant difference with those of classical dissection of previous year. Subgroup analysis of practical exam scores in alternating dissection was also no significant difference between group A and B. Assessment of question types showed that correction rates of questions in the dissected region was significantly higher on dissection group assignment. There were 9 questions (out of 86) in which there was a significant difference in correction rates between A and B groups. In conclusion, the laboratory paradigm of alternating dissection with reciprocal peer teaching demonstrated an effective method of learning gross anatomy laboratory for first year medical students.

The molecular mechanism for nuclear transport and its application / 대한해부학회지

Transportation between the cytoplasm and the nucleoplasm is critical for many physiological and pathophysiological processes including gene expression, signal transduction, and oncogenesis. So, the molecular mechanism for the transportation needs to be studied not only to understand cell physiological processes but also to develop new diagnostic and therapeutic targets. Recent progress in the research of the nuclear transportation (import and export) via nuclear pore complex and four important factors affecting nuclear transport (nucleoporins, Ran, karyopherins, and nuclear localization signals/nuclear export signals) will be discussed. Moreover, the clinical significance of nuclear transport and its application will be reviewed. This review will provide some critical insight for the molecular design of therapeutics which need to be targeted inside the nucleus.

Gastric stem cells and gastric cancer stem cells / 대한해부학회지

The gastric epithelium is continuously regenerated by gastric stem cells, which give rise to various kinds of daughter cells, including parietal cells, chief cells, surface mucous cells, mucous neck cells, and enteroendocrine cells. The self-renewal and differentiation of gastric stem cells need delicate regulation to maintain the normal physiology of the stomach. Recently, it was hypothesized that cancer stem cells drive the cancer growth and metastasis. In contrast to conventional clonal evolution hypothesis, only cancer stem cells can initiate tumor formation, self-renew, and differentiate into various kinds of daughter cells. Because gastric cancer can originate from gastric stem cells and their self-renewal mechanism can be used by gastric cancer stem cells, we review here how critical signaling pathways, including hedgehog, Wnt, Notch, epidermal growth factor, and bone morphogenetic protein signaling, may regulate the self-renewal and differentiation of gastric stem cells and gastric cancer stem cells. In addition, the precancerous change of the gastric epithelium and the status of isolating gastric cancer stem cells from patients are reviewed.

Expression and roles of NUPR1 in cholangiocarcinoma cells / 대한해부학회지

Nuclear protein-1 (NUPR1) is a small nuclear protein that is responsive to various stress stimuli. Although NUPR1 has been associated with cancer development, its expression and roles in cholangiocarcinoma have not yet been described. In the present study, we found that NUPR1 was over-expressed in human cholangiocarcinoma tissues, using immunohistochemistry. The role of NUPR1 in cholangiocarcinoma was examined by its specific siRNA. NUPR1 siRNA decreased proliferation, migration and invasion of human cholangiocarcinoma cell lines (HuCCT1 and SNU1196 cells). From these results, we conclude that NUPR1 is over-expressed in cholangiocarcinoma and regulates the proliferation and motility of cancer cells.

Characterization of the expression of cytokeratins 5, 8, and 14 in mouse thymic epithelial cells during thymus regeneration following acute thymic involution / 대한해부학회지

The thymus is a central lymphoid organ for T cell development. Thymic epithelial cells (TECs) constitute a major component of the thymic stroma, which provides a specialized microenvironment for survival, proliferation, and differentiation of immature T cells. In this study, subsets of TECs were examined immunohistochemically to investigate their cytokeratin (CK) expression patterns during thymus regeneration following thymic involution induced by cyclophosphamide treatment. The results demonstrated that both normal and regenerating mouse thymuses showed a similar CK expression pattern. The major medullary TECs (mTEC) subset, which is stellate in appearance, exhibited CK5 and CK14 staining, and the minor mTEC subset, which is globular in appearance, exhibited CK8 staining, whereas the vast majority of cortical TECs (cTECs) expressed CK8 during thymus regeneration. Remarkably, the levels of CK5 and CK14 expression were enhanced in mTECs, and CK8 expression was upregulated in cTECs during mouse thymus regeneration after cyclophosphamide-induced acute thymic involution. Of special interest, a relatively high number of CK5+CK8+ TEC progenitors occurred in the thymic cortex during thymus regeneration. Taken together, these findings shed more light on the role of CK5, CK8, and CK14 in the physiology of TECs during mouse thymus regeneration, and on the characterization of TEC progenitors for restoration of the epithelial network and for concomitant regeneration of the adult thymus.

Expression of IL-17A during Thymus Regeneration in the Rat / 체질인류학회지

IL-17A is a pro-inflammatroy cytokine secreted by activated T cells. The IL-17 family consist of IL-17A, IL-17B, IL-17C, IL-17D, IL-17E and IL-17F. IL-17A and IL-17F are produced primarily in activated T cells. In contrast, IL-17B, IL-17C, IL-17D and IL-17E are expressed in a wide assortment of tissues. Their functions partially overlap those of IL-17A, although they have not been as thoroughly investigated. The receptor for IL-17A (IL-17R) is widely expressed in a variety of tissues. IL-17A and IL-17E mRNAs were expressed in only EL4 cells. IL-17C mRNA expression was observed in the thymic subcapsular/cortex epithelial cells (SNEC), cortex or cortical reticular cells (CREC), medullary epithelial cells (MEC), medullary interdigitating-like cells (MDC), thymocytes and EL4 cells. However, IL-17C mRNA was not expressed in RAW 264.7 cells. Immunohistochemical study also demonstrated not only the presence of IL-17A mainly in the thymic epithelial cells, but also the upregulated expression of IL-17A in the thymic epithelial cells of the regenerating thymus. Thus, the results of the present study suggest that IL-17A expressed in the thymocytes and thymic epithelial cells could play an important role in the development of new T cells to replace T cells damaged by cyclophosphamide treatment during thymus regeneration.

Vitamin D3 regulates cell viability in gastric cancer and cholangiocarcinoma / 대한해부학회지

A low serum level of vitamin D has been associated with an increased incidence of gastrointestinal tract cancers. However, the effects of vitamin D3 have not been investigated in gastric cancer and cholangiocarcinoma. In the present study, we found that vitamin D3 treatment significantly suppressed the viability of gastric cancer and cholangiocarcinoma cells. Moreover, vitamin D3 had a synergistic effect with other anti-cancer drugs, such as paclitaxel, adriamycin, and vinblastine, for suppressing cell viability. To determine the underlying mechanism involved in the regulation of viability by vitamin D3, we examined the effects of vitamin D3 on expression of hedgehog signaling target genes, which has been associated with gastric cancer and cholangiocarcinoma. Vitamin D3 treatment decreased the level of mRNA expression of patched1, Gli1, cyclin D1, and Bcl2, suggesting the possibility that vitamin D3 may act through regulation of hedgehog signaling. From the above results, we conclude that vitamin D3 regulates cell viability in gastric cancer and cholangiocarcinoma.

CDH3/P-Cadherin regulates migration of HuCCT1 cholangiocarcinoma cells / 대한해부학회지

Intrahepatic cholangiocarcinoma is the second most common subtype of primary hepatobilliary cancer. Despite advances in surgical and medical therapy, its survival rate remains poor. Compared to hepatocellular carcinoma (HCC), the most common liver malignancy, the underlying mechanisms of cholangiocarcinoma carcinogenesis are poorly characterized. P-cadherin (CDH3) is a cadherin super family member. Although CDH3 is frequently over-expressed in cholangiocarcinoma tissues, its roles have never been characterized. To determine the roles of CDH3 in cholangiocarcinoma, we investigated CDH3 function in HuCCT1 cells using specific siRNA. Transfection with CDH3 siRNA did not affect proliferation of HuCCT1 cells. However, cell migration and invasion were significantly reduced when CDH3 was down-regulated. In addition, expressions of several biomarkers for epithelial-mesenchymal transition (EMT) were not changed by CDH3 down-regulation. These results suggest that CDH3 regulates cell migration independent of EMT in cholangiocarcinoma cells.

Expression of the p75NTR Neurotrophin Receptor in the Thymic Medullary Epithelial Cells and Interdigitating Dendritic Cells during Rat Thymus Regeneration Following Acute Thymic Involution / 대한해부학회지

The existence of a functional link between the nervous and immune systems has been well established. The present study was to characterize the expression of p75NTR during thymus regeneration from acute involution induced by cyclophosphamide in the rat. Immunohistochemical and double immunofluorescence analyses demonstrated that expression of the p75NTR was decreased in the thymic medullary epithelial cells and interdigitating dendritic cells during thymus regeneration. The presence of p75NTR protein in extracts from the control and regenerating rat thymus was confirmed by western blot. Furthermore, RT-PCR analysis supported these results by demonstrating that thymic extracts contain p75NTR mRNA at lower levels during thymus regeneration. Thus, our results suggest that the p75NTR located on the thymic medullary epithelial cells and interdigitating dendritic cells could play a role in the development of new T cells to replace the thymocytes damaged during thymus regeneration

Effects of Indomethacin on Ischemia-induced Brain Injury / 대한해부학회지

Cerebral ischemia can have severe results and disrupt quality of life. Current medicine is not effective at overcoming these problems. To find out more effective therapies, it is necessary to understand the microenvironment of cerebral injury after the ischemia. In the present study, to investigate the effects of inflammatory reaction, indomethacin, an anti-inflammatory drug, was used in a photothrombotic focal infarction rat model. It was revealed that cerebral ischemia increased neurogenesis in the subventricular (SVZ) and subgranular zones (SGZ), and in the penumbral region. Indomethacin treatment reduced the cerebral ischemia-induced neurogenesis by 86.2%, 53.8%, and 52.8% respectively. Cerebral ischemia increased gliosis and angiogenesis in the penumbral region and indomethacin reduced gliosis and angiogenesis by 48.2% and 58.1%, respectively. These results suggest that indomethacin treatment after the cerebral ischemia can reduce neurogenesis, angiogenesis, and gliosis in the penumbral region.

Effects of retinoic acid on ischemic brain injury-induced eurogenesis

Neurogenesis can be induced by pathological conditions such as cerebral ischemia. However the molecular mechanisms or modulating reagents of the reactive neurogenesis after the cerebral ischemia are poorly characterized. Retinoic acid (RA) has been shown to increase neurogenesis by enhancing the proliferation and neuronal differentiation of forebrain neuroblasts. Here, we examined whether RA can modulate the reactive neurogenesis after the cerebral ischemia. In contrast to our expectation, RA treatment decreased the reactive neurogenesis in subventricular zone (SVZ), subgranular zone (SGZ) and penumbral region. Furthermore, RA treatment also decreased the angiogenesis and gliosis in penumbral region.

Morphological Changes of Anterior Horn Cells of Lumbar Spinal Cord after Anterior Root Avulsion in Adult Rat / 대한해부학회지

The morphological changes in the anterior horn of the L4 and L5 spinal segments were observed following anterior root avulsion in the adult male Sprague-Dawley rat (300~350 gm) at 5 days, 1 week, 2 weeks and 3 weeks postlesion. The animals were perfused with 4% paraformaldehyde, 0.15% picric acid in 0.1 M phosphate buffer solution and cryostat sections were prepared. Immunohistochemistry was used to identify changes of the phenotype in the anterior horn cells. Primary antibodies, goat anti-choline acetyltransferase (ChaT, 1 : 500, Chemicon), mouse antirat ED-1 (1 : 200, Serotec), rabbit anti-glial fibrillary acidic protein (GFAP, 1 : 200, DAKO) and rabbit anti-vascular endothelial growth factor (VEGF, 1 : 500, Santa Cruz Biotechnology) were used. Avidin-Biotin complex method was performed for immunohistochemical reaction and color reaction was developed with DAB-H2O2. Following results were observed in the anterior horn of lumbar spinal cord; 1. The number of ChaT-immunoreactive (ir) cells were reduced 20% level of control animals at 3 weeks after avulsion. 2. ED-1-ir microglia were significantly increased at 1 week and processes of ED-1-ir microglia surrounded around the axotomized neuronal cell bodies. 3. Gliosis defined by extensive GFAP immunoreactivity was observed both ipsilateral and contralateral side of lesion but the VEGF-ir cells were significantly increased in the ipsilateral side of lesion. Therefore, this study suggested that the majority of axotomized motor neurons were degenerated and the cellular proliferation and phenotype changes including glial cell activation were observed in the lumbar spinal cord after anterior root avulsion of adult rats.

Comparison of the Effects of NOS Inhibitor or HS-1580 on Nigrostriatal Dopaminergic System in MPTP-induced Parkinson's Disease Animal Model / 대한해부학회지

The antioxidant effects of HS-1580 derived from Brown seaweeds in comparison with NOS inhibitor, L-NAME, were tested in the Parkinson's disease animal model. C57BL/6 mice were implanted with osmotic pump containing vehicle, HS-1580 or L-NAME intraperitoneally 2 days before MPTP injection. The Parkinson's animal model were prepared by intraperitonal injection of MPTP (20 mg/kg, 4 times with 2 hours intervals in a ay).The mice were perfused with Zamboni fixative 2 days or 7days after MPTP injection. The 30 micrometer cryostat section were immunostained with free-floating method. Rabbit anti-tyrosine hydroxylase (TH)and rat anti-mouse MAC-1 were used as the primary antibodies. The following results were obtained. The number of TH-immunoreactive (ir)neurons in substantia nigra (SN)and the relative density of TH-ir axon terminals in striatum were decreased by MPTP injection. But the ecrease was significantly attenuated with 10%HS-1580 or L-NAME (50 mg/kg)pretreatment before MPTP injection. MAC-1-ir activated microglia were observed in substantia nigra 2 days after MPTP injection. Activated microglia were showed as thickened processes with round cell bodies. The morphological changes of MAC-1-ir activated microglia were inhibited by HS-15980 or L-NAME pretreatment before MPTP injction. Above results mean that the damage of nigrostriatal dopaminergic system was rescued by pretreatment of HS-1580 or L-NAME in MPTP-induced Parkinson's disease animal model.

Roles of Gli3 in Dorsal Neural Tube / 대한해부학회지

Essential roles of Gli3 in ventral neural tube have been stressed from studies of Shh(-/-) and Shh(-/-); Gli3(-/-) mutants. However, roles of Gli3 in dorsal neural tube have not been fully appreciated despite of its high expression. To find out roles of Gli3 in dorsal neural tube, we studied cell proliferation and neuronal differentiation in dorsal neural tube of Gli3(-/-) mutant. In Gli3(-/-) mutant, proliferation of progenitor cells in dorsal neural tube is increased compared to wild type embryos based on phosphohistone 3 immunohistochemistry and BrdU experiment. The appearances of HuC/D positive and Isl1 postive cells which represent postmitotic neurons and dI3 interneurons were delayed in Gli3(-/-) mutant compared to wild type embryo. The appearance of a proneural gene, Ngn2 was also delayed in Gli3(-/-) mutant compared to wild type embryo. Neuronal differentiation of progenitor cells in dorsal neural tube was delayed in Gli3(-/-) mutant compared to wild type embryos based on HuC/D, Isl1 and Ngn2 expressions. These results suggest that Gli3 plays important roles in cell proliferation and neuronal differentiation in dorsal neural tube. Thus our data shed a new light on the role of Gli3 in the development of neural tube.

Roles of Gli3 in the Establishment of Progenitor Domains of Developing Spinal Cord / 대한해부학회지

University Sonic hedgehog (Shh) signaling has been shown to play instructive roles in developing spinal cord. Depending on the Shh concentration gradient, different progenitor domains and ventral neurons are induced. However, the way how the Shh gradient is translated into different progenitor domains, is not clear. To investigate the translation of the Shh gradient, we studied expressions of homeoproteins which are critical for establishment of progenitor domains, in the ventral neural tube of Shh(-/-)and Shh(-/-);Gli3(-/-) mutants, using in situ hybridization. In Shh(-/-) mutant, the expressions of class II homeoproteins (Nkx6.1, Nkx6.2, Olig2, Nkx2.2 were totally repressed. The expressions of class I homeoproteins (Dbx1, Dbx2, Irx3, Pax6 were ventralized. In Shh(-/-);Gli3(-/-) mutant, the expressions of class II homeoproteins except Nkx2.2 were restored. The expressions of class I home-oproteins were restored to its original position although their restoration is not complete. From above results, we conclude that Gli3 can regulate the expressions of class II homeoproteins, which suggests that the Shh gradient will be translated into Gli activity in the developing spinal cord.