👤 M Kodama

Lysophosphatidic acid (LPA) is a crucial bioactive lipid mediator involved in various physiological processes; however, its role in macrophage polarization remains poorly understood; therefore, this study aimed to elucidate the modulatory effect of LPA on macrophage polarization, particularly its ability to shift M1 macrophages towards an M2-like phenotype, using murine macrophage RAW264.7 cells to confirm the expression of LPA receptor 1 (LPAR1) through immunofluorescence staining, which revealed that treatment of resting MO macrophages with LPA decreased inflammatory cytokines (IL-6, TNF-α) and increased TGF-β, with similar effects observed in LPS-stimulated cells and reversed by the LPAR1 inhibitor AM095, and immunostaining demonstrated a notable shift from an M1- to M2-like phenotype, as evidenced by an increase in the arginase-1/CD68 ratio; furthermore, LPA significantly decreased lactate production and increased ATP production in M1 macrophages, promoting a shift towards oxidative phosphorylation and suggesting metabolic reprogramming towards an M2-like phenotype, significantly influencing macrophage polarization and promoting a shift from a pro-inflammatory M1-like phenotype to an anti-inflammatory M2-like phenotype; these results suggest that treatment with LPA may help ameliorate diseases characterized by aberrant macrophage polarization, providing insights for the development of potential therapeutic strategies for inflammatory and autoimmune diseases. Show less

RNA editing is a significant mechanism underlying genetic variation and protein molecule alteration; C-to-U RNA editing, specifically, is important in the regulation of mammalian genetic diversity. The ability to define and limit accesses of enzymatic machinery to avoid the modification of unintended targets is key to the success of RNA editing. Identification of the core component of the apoB RNA editing holoenzyme, APOBEC, and investigation into new candidate genes encoding other elements of the complex could reveal further details regarding APOBEC-mediated mRNA editing. Menkes disease is a recessive X-chromosome-linked hereditary syndrome in humans, caused by defective copper metabolism due to mutations in the Show less

Neuromuscular scoliosis is associated with cerebral palsy caused by metabolic diseases. Patients with scoliosis require meticulous consideration in abdominal surgery, as scoliosis can reduce the abdominal cavity volume, compress abdominal organs, and cause abdominal complications. Special attention should be paid to the graft position, especially in the setting of liver transplantation (LT). We herein describe a pediatric case of LT for carbamoyl phosphate synthetase I (CPS1) deficiency with severe scoliosis. A 13-year-old girl with CPS1 deficiency was transferred to our department as a candidate for liver transplantation. She underwent living donor liver transplantation with a left lobe from her mother. Following LT, portal vein (PV) complications occurred due to the kinking anastomosis, requiring several rounds of graft repositioning, PV reconstruction, thrombectomy, and finally stent placement due to severe scoliosis. Technical efforts were made to ensure PV blood flow with stent placement via the umbilical vein. Three months after LT, she was discharged from our hospital with sufficient PV flow. This report suggests the need for a careful surgical approach in patients with skeletal abnormalities, such as the management of complications arising from anatomical abnormalities and selection of the appropriate graft size. Preoperative assessment and surgical planning of both donors and recipients according to patient characteristics should be carefully conducted. Show less

This study aims to elucidate the clinical and molecular characteristics, treatment outcomes and prognostic factors of patients with histone H3 K27-mutant diffuse midline glioma. We retrospectively analyzed 93 patients with diffuse midline glioma (47 thalamus, 24 brainstem, 12 spinal cord and 10 other midline locations) treated at 24 affiliated hospitals in the Kansai Molecular Diagnosis Network for CNS Tumors. Considering the term "midline" areas, which had been confused in previous reports, we classified four midline locations based on previous reports and anatomical findings. Clinical and molecular characteristics of the study cohort included: age 4-78 years, female sex (41%), lower-grade histology (56%), preoperative Karnofsky performance status (KPS) scores ≥ 80 (49%), resection (36%), adjuvant radiation plus chemotherapy (83%), temozolomide therapy (76%), bevacizumab therapy (42%), HIST1H3B p.K27M mutation (2%), TERT promoter mutation (3%), MGMT promoter methylation (9%), BRAF p.V600E mutation (1%), FGFR1 mutation (14%) and EGFR mutation (3%). Median progression-free and overall survival time was 9.9 ± 1.0 (7.9-11.9, 95% CI) and 16.6 ± 1.4 (13.9-19.3, 95% CI) months, respectively. Female sex, preoperative KPS score ≥ 80, adjuvant radiation + temozolomide and radiation ≥ 50 Gy were associated with favorable prognosis. Female sex and preoperative KPS score ≥ 80 were identified as independent good prognostic factors. This study demonstrated the current state of clinical practice for patients with diffuse midline glioma and molecular analyses of diffuse midline glioma in real-world settings. Further investigation in a larger population would contribute to better understanding of the pathology of diffuse midline glioma. Show less

Lymphangiogenesis is essential for the development of the lymphatic system and is important for physiological processes such as homeostasis, metabolism and immunity. Cellular communication network factor 2 (CCN2, also known as CTGF), is a modular and matricellular protein and a well-known angiogenic factor in physiological and pathological angiogenesis. However, its roles in lymphangiogenesis and intracellular signaling in lymphatic endothelial cells (LECs) remain unclear. Here, we investigated the effects of CCN2 on lymphangiogenesis. In in vivo Matrigel plug assays, exogenous CCN2 increased the number of Podoplanin-positive vessels. Subsequently, we found that CCN2 induced phosphorylation of ERK in primary cultured LECs, which was almost completely inhibited by the blockade of integrin αvβ5 and partially decreased by the blockade of integrin αvβ3. CCN2 promoted direct binding of ERK to dual-specific phosphatase 6 (DUSP6), which regulated the activation of excess ERK by dephosphorylating ERK. In vitro, CCN2 promoted tube formation in LECs, while suppression of Dusp6 further increased tube formation. In vivo, immunohistochemistry also detected ERK phosphorylation and DUSP6 expression in Podoplanin-positive cells on CCN2-supplemented Matrigel. These results indicated that CCN2 promotes lymphangiogenesis by enhancing integrin αvβ5-mediated phosphorylation of ERK and demonstrated that DUSP6 is a negative regulator of excessive lymphangiogenesis by CCN2. Show less

The prognosis of patients with high-grade or advanced-stage endometrial cancer remains poor. As cancer stem-like cells (CSCs) are thought to be associated with endometrial cancers, it is essential to investigate the molecular mechanisms that regulate endometrial CSCs. Dual-specificity phosphatase 6 (DUSP6) functions as a negative-feedback regulator of MAPK-ERK1/2 signaling, but its role in endometrial cancer remains unknown. We investigated whether DUSP6 is involved in cancer cell stemness using endometrial cancer cell lines and specimens from endometrial cancer patients. DUSP6 induced the expression of CSC-related genes including ALDH1, Nanog, SOX2 and Oct4A, increased the population of cells in the G0/G1 phase, and promoted sphere formation ability. DUSP6 knockdown resulted in reduced cell invasion and metastasis, whereas DUSP6 overexpression inhibited apoptosis under serum-free conditions. Moreover, DUSP6 decreased phosphorylated ERK1/2 and increased phosphorylated Akt levels, which potentially induces CSC features. In patients with endometrial cancers, DUSP6 expression was determined using immunohistochemistry, and based on the results, the patients were dichotomized into high- and low-DUSP6-expression groups. Progression-free survival and overall survival were significantly shorter in the high-DUSP6-expression group. These results suggest that DUSP6 has potential value as a biomarker of CSCs and as a target of therapies designed to eliminate CSCs in endometrial cancer. Show less

Liver X receptor (LXR) is a nuclear receptor that acts as a sterol sensor and metabolic regulator of cholesterol and lipid homeostasis. The foam cell transformation of macrophages (Mvarphi) is considered a critical process in atherosclerotic lesions. The relationship, however, of the foam cell transformation of Mvarphi and LXR is not fully understood. The purpose of the present study was to examine the expression of LXRalpha, retinoid X receptor (RXR)alpha, ATP-binding cassette transporter (ABCA1), and macrophage scavenger receptor A (MSR-A), and lipid accumulation in human monocyte-derived Mvarphi. The expression of LXRalpha, ABCA1, MSR-A in 7 day cultured granulocyte-macrophage colony-stimulating factor (GM-CSF)-induced Mvarphi (GM-Mvarphi) was significantly higher than that in 7 day cultured M-CSF-induced Mvarphi (M-Mvarphi). The expression levels of LXRalpha, ABCA1 and MSR-A protein decreased from 48 h to 5 days after the addition of lipopolysaccharide (LPS) in GM-Mvarphi, but only MSR-A protein decreased at 5 days after the addition of LPS in M-Mvarphi. Intracellular lipid accumulation was clearly observed when GM-Mvarphi was pre-stimulated with LPS for 48 h and incubated with oxidized LDL for an additional 5 days. These findings suggest that the inhibitory activity of LXRalpha, ABCA1 and MSR-A by LPS may be related to the transformation of Mvarphis, especially GM-Mvarphi into foam cells. Show less

Coordinated interactions between microtubule (MT) and actin cytoskeletons are involved in many polarized cellular processes. Spectraplakins are enormous (>500 kDa) proteins able to bind both MTs and actin filaments (F-actin) directly. To elucidate the physiological significance and functions of mammalian spectraplakin ACF7, we've conditionally targeted it in skin epidermis. Intriguingly, ACF7 deficiency compromises the targeting of microtubules along F-actin to focal adhesions (FAs), stabilizes FA-actin networks, and impairs epidermal migration. Exploring underlying mechanisms, we show that ACF7's binding domains for F-actin, MTs, and MT plus-end proteins are not sufficient to rescue the defects in FA-cytoskeletal dynamics and migration functions of ACF7 null keratinocytes. We've uncovered an intrinsic actin-regulated ATPase domain in ACF7 and demonstrate that it is both functional and essential for these roles. Our findings provide insight into the functions of this important cytoskeletal crosslinking protein in regulating dynamic interactions between MTs and F-actin to sustain directional cell movement. Show less

In the yeast, Saccharomyces cerevisiae, cell size is affected by the kind of carbon source in the medium. Here, we present evidence that the Gpr1 receptor and Gpa2 Galpha subunit are required for both maintenance and modulation of cell size in response to glucose. In the presence of glucose, mutants lacking GPR1 or GPA2 gene showed smaller cells than the wild-type strain. Physiological studies revealed that protein synthesis rate was reduced in the mutant strains indicating that reduced growth rate, while the level of mRNAs for CLN1, 2 and 3 was not affected in all strains. Gene chip analysis also revealed a down-regulation in the expression of genes related to biosynthesis of not only protein but also other cellular component in the mutant strains. We also show that GPR1 and GPA2 are required for a rapid increase in cell size in response to glucose. Wild-type cells grown in ethanol quickly increased in size by addition of glucose, while little change was observed in the mutant strains, in which glucose-dependent cell cycle arrest caused by CLN1 repression was somewhat alleviated. Our study indicates that the yeast G-protein coupled receptor system consisting of Gpr1 and Gpa2 regulates cell size by affecting both growth rate and cell division. Show less

ACF7 is a member of the spectraplakin family of cytoskeletal crosslinking proteins possessing actin and microtubule binding domains. Here, we show that ACF7 is an essential integrator of MT-actin dynamics. In endodermal cells, ACF7 binds along microtubules but concentrates at their distal ends and at cell borders when polarized. In ACF7's absence, microtubules still bind EB1 and CLIP170, but they no longer grow along polarized actin bundles, nor do they pause and tether to actin-rich cortical sites. The consequences are less stable, long microtubules with skewed cytoplasmic trajectories and altered dynamic instability. In response to wounding, ACF7 null cultures activate polarizing signals, but fail to maintain them and coordinate migration. Rescue of these defects requires ACF7's actin and microtubule binding domains. Thus, spectraplakins are important for controlling microtubule dynamics and reinforcing links between microtubules and polarized F-actin, so that cellular polarization and coordinated cell movements can be sustained. Show less

It is generally accepted that both dysfunction of the Wnt signaling pathway, including mutations in the adenomatous polyposis coli (APC) and beta-catenin genes, and genetic instability play important roles in colorectal carcinogenesis. However, alteration of the components in the Wnt signaling pathway in colorectal cancer (CRC) with microsatellite instability (MSI) has not been elucidated. In order to assess the status of the Wnt signaling components in CRC with MSI, mutational analyses of the beta-catenin, APC, Axin 1, and T cell factor 4 (TCF4) genes were performed. Three of 33 samples had mutations in exon 3 of the beta-catenin gene and two in the APC gene. Eight mutations in seven samples were detected by single-strand conformation polymorphism and subsequent direct sequence analysis of the entire coding region of the Axin 1 gene. Furthermore, TCF4, which is one of the transcriptional factors in the Wnt signaling pathway and has a mononucleotide repeat sequence (a nine- adenine repeat, (A)9) in its C-terminal region, was mutated in 13 of the 33 samples. Thus, alteration in the Wnt signaling pathway is frequently observed in CRC with MSI, including hereditary nonpolyposis colorectal cancer, as well as in familial adenomatous polyposis and sporadic CRC without MSI. Show less

Two functionally different MAP kinase phosphatases (MKPs) were investigated to clarify their roles in behavioral sensitization to methamphetamine (METH). MKP-1 mRNA levels increased substantially by about 60-300% in a range of brain regions, including several cortices, the striatum and thalamus 0.5-1 h after acute METH administration. After chronic METH administration its increase was less pronounced, but a more than 50% increase was still seen in the frontal cortex. MKP-1 protein levels also increased 3 h after acute or chronic METH administration. MKP-3 mRNA levels increased by about 30-50% in several cortices, the striatum and hippocampus 1 h after acute METH administration, but only in the hippocampus CA1 after chronic METH administration. Pre-treatment with the D(1) dopamine receptor antagonist, SCH23390, attenuated the METH-induced increase of MKP-1 and MKP-3 mRNA in every brain region, while pre-treatment with the NMDA receptor antagonist, MK-801, attenuated it in some regions. These findings suggest that in METH-induced sensitization, MKP-1 and MKP-3 play important roles in the neural plastic modification in widespread brain regions in the earlier induction process, but in the later maintenance process, they do so only in restricted brain regions such as MKP-1 in the frontal cortices and MKP-3 in the hippocampus. Show less