GADD45β Determines Chemoresistance and Invasive Growth of Side Population Cells of Human Embryonic Carcinoma

Side population (SP) cells are an enriched population of stem, and the existence of SP cells has been reported in human cancer cell lines. In this study, we performed an SP analysis using 11 human cancer cell lines and confirmed the presence of SP cells in an embryonic carcinoma cell line, NEC8. NEC8 SP cells showed characteristics of cancer stem cells, such as high growth rate, chemoresistance and high invasiveness. To further characterize the NEC8 SP cells, we used DNA microarrays. Among 38,500 genes, we identified 12 genes that were over-expressed in SP cells and 1 gene that was over-expressed in non-SP cells. Among these 13 genes, we focused on GADD45b. GADD45b was over-expressed in non-SP cells, but the inhibition of GADD45b had no effect on non-SP cells. Paradoxically, the inhibition of GADD45b significantly reduced the viability of NEC8 SP cells. The inhibition of ABCG2, which determines the SP phenotype, had no effect on the invasiveness of NEC8 SP cells, but the inhibition of GADD45b significantly reduced invasiveness. These results suggest that GADD45b, but not ABCG2, might determine the cancer stem cell-like phenotype, such as chemoresistance and the high invasiveness of NEC8 SP cells, and might be a good therapeutic target

Phosphorylation of proteins and apoptosis induced by c-Jun N-terminal kinase1 activation in rat cardiomyocytes by H2O2 stimulation

AbstractCytokines and various cellular stresses are known to activate c-Jun N-terminal kinase-1 (JNK1), which is involved in physiological function. Here, we investigate the activation of JNK1 by oxidative stress in H9c2 cells derived from rat cardiomyocytes. H2O2 (100 μM) significantly induces the tyrosine phosphorylation of JNK1 with a peak 25 min after the stimulation. The amount of JNK1 protein remains almost constant during stimulation. Immunocytochemical observation shows that JNK1 staining in the nucleus is enhanced after H2O2 stimulation. To clarify the physiological role of JNK1 activation under these conditions, we transfected antisense JNK1 DNA into H9c2 cells. The antisense DNA (2 μM) inhibits JNK1 expression by 80% as compared with expression in the presence of the sense DNA, and significantly blocks H2O2-induced cell death. Consistent with the decrease in cell number, we detected condensation of the nuclei, a hallmark of apoptosis, 3 h after H2O2 stimulation in the presence of the sense DNA for JNK1. The antisense DNA of JNK1 inhibits the condensation of nuclei by H2O2. Under these conditions, the H2O2-induced phosphorylation of proteins with molecular masses of 55, 72, and 78 kDa is blocked by treatment with the antisense DNA for JNK1 as compared with the sense DNA for JNK1. These findings suggest that JNK1 induces apoptotic cell death in response to H2O2, and that the cell death may be involved in the phosphorylations of 55, 72, and 78 kDa proteins induced by JNK1 activation

Rearrangement of the breakpoint cluster region in Philadelphia chromosome positive acute leukemia.

The rearrangement of breakpoint cluster region (ber) was examined in leukemic cells obtained from 3 patients initially diagnosed as having Ph+ acute leukemia, 2 with acute lymphocytic leukemia (ALL) and one with acute mixed leukemia. DNA was digested with Bgl II and BamH I. The ber rearrangement was present in the case of acute mixed leukemia (Case 1), but was absent in the 2 cases of ALL (Cases 2 and 3). These results suggest that Case 1 represented a type of blast crisis of chronic myelocytic leukemia which was unusual in the sense of the occurrence of a myeloid-lymphoid conversion and lack of an apparent chronic phase. Cases 2 and 3 appeared to be de novo Ph+ ALL.</p

Clinical Evaluation of Immune Response in Patients with Lung Cancer

In patients with lung cancer, the immune response was observed with an analysis of various factors which mostly related to its prognosis. Its response was extremly depressed in the course of following surgery in advanced cases of stage III and IVas well as in unresectable cases for lung cancer, compared with those of stage I and II . Furthermore, it showed that the high levels of immune response were seen in those of long term survivors given OK-432 during follow-up period. It was obvious from this study that the use of OK-432 was suitable for activation of the immune reaction against host as one of the immunopotentiators. Meanwhile, from the immunological mechanism of view, the hyperactivity of immune response enable the patient to be free from recurrence of cancer for a long term following surgery, in contrast the low level of the immune response showed to be poor prognosis owing to early appearance of recurrence. Furthermore, the effectiveness in use of OK-432 was clinically presented in patients with malignant pleural effusion, which showed direct cytocidal action of OK-432 given intrapleurally with a 10 or 14 days interval

精神疾患におけるマイクログリア由来ニューレグリン発現

Several studies have revealed that neuregulins (NRGs) are involved in brain function and psychiatric disorders. While NRGs have been regarded as neuron- or astrocyte-derived molecules, our research has revealed that microglia also express NRGs, levels of which are markedly increased in activated microglia. Previous studies have indicated that microglia are activated in the brains of individuals with autism spectrum disorder (ASD). Therefore, we investigated microglial NRG mRNA expression in multiple lines of mice considered models of ASD. Intriguingly, microglial NRG expression significantly increased in BTBR and socially-isolated mice, while maternal immune activation (MIA) mice exhibited identical NRG expression to controls. Furthermore, we observed a positive correlation between NRG expression in microglia and peripheral blood mononuclear cells (PBMCs) in mice, suggesting that NRG expression in human PBMCs may mirror microglia-derived NRG expression in the human brain. To translate these findings for application in clinical psychiatry, we measured levels of NRG1 splice-variant expression in clinically available PBMCs of patients with ASD. Levels of NRG1 type III expression in PBMCs were positively correlated with impairments in social interaction in children with ASD (as assessed using the Autistic Diagnostic Interview-Revised test: ADI-R). These findings suggest that immune cell-derived NRGs may be implicated in the pathobiology of psychiatric disorders such as ASD.博士（医学）・乙第1404号・平成29年6月28日Copyright © 2017 Elsevier Inc. All rights reserved

An Experimental Evaluation of Tracheal Blood Flow with Special Referrence to Operative Procedure of Tracheal Mobilization

Based on the study with special referrence to blood flow in the trachea, the factors influential on the operative procedure of tracheal mobilization were carefully evaluated to ensure optimal surgical results. It has already been assumed with an aid of microangiographic technique that the main trancheal blood flow comprise two routes, namely, adventitial and submucosal layers. The amount of blood flow in the trachea divided into individual two layers were measured by hydrogen clearance test with wire electrodes placed in either adventitial or submucosal layer. When employed the procedure of extensive mobilization of the trachea, the level of tracheal blood flow reduced in adventitial layer rather lthan in submucosal layer. Blood flow in submucosal layer, however, remain closely near the normal level, which is thought to compensate a decreased blood supply in the tracheal adventitia. Meanwhile, when proposed an excessive tension of more than 800g at the site of anastomosis, a decrease in submucosal blood flow has become manifest despite of a slight decrease in adventitial blood flow simultaneously. Greater emphasis has been focused upo

Association of Transcription Factor Gene LMX1B with Autism

Multiple lines of evidence suggest a serotoninergic dysfunction in autism. The role of LMX1B in the development and maintenance of serotoninergic neurons is well known. In order to examine the role, if any, of LMX1B with autism pathophysiology, a trio-based SNP association study using 252 family samples from the AGRE was performed. Using pair-wise tagging method, 24 SNPs were selected from the HapMap data, based on their location and minor allele frequency. Two SNPs (rs10732392 and rs12336217) showed moderate association with autism with p values 0.018 and 0.022 respectively in transmission disequilibrium test. The haplotype AGCGTG also showed significant association (p = 0.008). Further, LMX1B mRNA expressions were studied in the postmortem brain tissues of autism subjects and healthy controls samples. LMX1B transcripts was found to be significantly lower in the anterior cingulate gyrus region of autism patients compared with controls (p = 0.049). Our study suggests a possible role of LMX1B in the pathophysiology of autism. Based on previous reports, it is likely to be mediated through a seretoninergic mechanism. This is the first report on the association of LMX1B with autism, though it should be viewed with some caution considering the modest associations we report