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1.
BMC Infect Dis ; 24(1): 96, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38233756

ABSTRACT

BACKGROUND: Whether human T-lymphotropic virus type 1 (HTLV-1) carriers can develop sufficient humoral immunity after coronavirus disease 2019 (COVID-19) vaccination is unknown. METHODS: To investigate humoral immunity after COVID-19 vaccination in HTLV-1 carriers, a multicenter, prospective observational cohort study was conducted at five institutions in southwestern Japan, an endemic area for HTLV-1. HTLV-1 carriers and HTLV-1-negative controls were enrolled for this study from January to December 2022. During this period, the third dose of the COVID-19 vaccine was actively administered. HTLV-1 carriers were enrolled during outpatient visits, while HTLV-1-negative controls included health care workers and patients treated by participating institutions for diabetes, hypertension, or dyslipidemia. The main outcome was the effect of HTLV-1 infection on the plasma anti-COVID-19 spike IgG (IgG-S) titers after the third dose, assessed by multivariate linear regression with other clinical factors. RESULTS: We analyzed 181 cases (90 HTLV-1 carriers, 91 HTLV-1-negative controls) after receiving the third dose. HTLV-1 carriers were older (median age 67.0 vs. 45.0 years, p < 0.001) and more frequently had diabetes, hypertension, or dyslipidemia than did HTLV-1-negative controls (60.0% vs. 27.5%, p < 0.001). After the third dose, the IgG-S titers decreased over time in both carriers and controls. Multivariate linear regression in the entire cohort showed that time since the third dose, age, and HTLV-1 infection negatively influenced IgG-S titers. After adjusting for confounders such as age, or presence of diabetes, hypertension, or dyslipidemia between carriers and controls using the overlap weighting propensity score method, and performing weighted regression analysis in the entire cohort, both time since the third dose and HTLV-1 infection negatively influenced IgG-S titers. CONCLUSIONS: The humoral immunity after the third vaccination dose is impaired in HTLV-1 carriers; thus, customized vaccination schedules may be necessary for them.


Subject(s)
COVID-19 , Diabetes Mellitus , Dyslipidemias , HTLV-I Infections , Human T-lymphotropic virus 1 , Hypertension , Humans , Aged , COVID-19/prevention & control , COVID-19 Vaccines , Immunity, Humoral , Prospective Studies , Vaccination , Immunoglobulin G , Antibodies, Viral
2.
J Infect Chemother ; 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39097170

ABSTRACT

Most cases of nontuberculous mycobacterial pulmonary disease (NTM-PD) have a progressive clinical course, and initiation of treatment is recommended rather than watchful waiting. The NTM-PD medications are frequently associated with adverse reactions, occasionally serious. Optimization of the methods for monitoring and managing adverse events in NTM-PD treatment is thus an important medical issue. Here we report a first case of postprandial hypoglycemia caused by the combination of clarithromycin (CAM) and rifampicin (RFP) in a patient with NTM-PD. A 73-year-old Japanese woman with NTM-PD was hospitalized for treatment with a combination of oral CAM, RFP, and ethambutol. She took the first doses of antibiotics before breakfast, and 3 h later went into a hypoglycemic state. Postprandial hypoglycemia occurred with high reproducibility and was accompanied by relative insulin excess. Continuous glucose monitoring with or without food and in combination with various patterns of medication revealed that the combination of CAM and RFP specifically induced postprandial hypoglycemia. Shifting the timing of administration of the CAM and RFP combination from morning to before sleep corrected the hypoglycemia and enabled continuation of the antimicrobial treatment. In conclusion, our report suggests the importance of introducing NTM-PD medication under inpatient management in order to closely monitor and early detect postprandial hypoglycemia and other serious adverse events.

3.
Brief Bioinform ; 22(6)2021 11 05.
Article in English | MEDLINE | ID: mdl-34180966

ABSTRACT

Accurate variant effect prediction has broad impacts on protein engineering. Recent machine learning approaches toward this end are based on representation learning, by which feature vectors are learned and generated from unlabeled sequences. However, it is unclear how to effectively learn evolutionary properties of an engineering target protein from homologous sequences, taking into account the protein's sequence-level structure called domain architecture (DA). Additionally, no optimal protocols are established for incorporating such properties into Transformer, the neural network well-known to perform the best in natural language processing research. This article proposes DA-aware evolutionary fine-tuning, or 'evotuning', protocols for Transformer-based variant effect prediction, considering various combinations of homology search, fine-tuning and sequence vectorization strategies. We exhaustively evaluated our protocols on diverse proteins with different functions and DAs. The results indicated that our protocols achieved significantly better performances than previous DA-unaware ones. The visualizations of attention maps suggested that the structural information was incorporated by evotuning without direct supervision, possibly leading to better prediction accuracy.


Subject(s)
Computational Biology , Deep Learning , Protein Domains , Proteins/chemistry , Algorithms , Amino Acid Sequence , Neural Networks, Computer , Protein Binding , Protein Interaction Domains and Motifs , Reproducibility of Results
4.
Endocr J ; 70(8): 825-832, 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37258249

ABSTRACT

There is no computed tomography (CT)-based numerical index for predicting Cushing's syndrome (CS) in patients with adrenal incidentalomas. We tested the hypothesis that the iliopsoas muscle (Ip-M) to visceral fat (V-fat) ratio (IVR) on CT may predict CS in elderly female patients with adrenal tumors. We examined the V-fat area, subcutaneous fat (S-fat) area, Ip-M area, V-fat/S-fat ratio, and IVR at the third lumbar vertebra (L3) level using abdominal CT in female patients aged ≥50 years with cortisol-producing adrenal tumor diagnosed with CS or non-functioning adrenal tumor (NFT) in the derivation cohort. We performed receiver operating characteristic (ROC) analysis to evaluate the diagnostic value of the V-fat/S-fat ratio and IVR for predicting CS. We assessed the usefulness of the IVR in a separate validation cohort. In the derivation cohort, the IVR was significantly lower in the 9 patients with CS than in the 15 patients with NFT (p < 0.001). In ROC analysis with a cut-off value of 0.067, the IVR showed a sensitivity of 100%, specificity of 80.0%, positive likelihood ratio (PLR) of 5.000, and negative likelihood ratio (NLR) of 0.000. The area under the curve was significantly higher for the IVR than for the V-fat/S-fat ratio (0.933 vs. 0.704, respectively, p = 0.036). In 23 patients in the validation cohort, the IVR demonstrated a PLR of 5.714 and an NLR of 0.327. The novel IVR index, based on single-slice CT at the L3 level, predicted CS in elderly female patients with adrenal tumors.


Subject(s)
Adrenal Gland Neoplasms , Cushing Syndrome , Aged , Humans , Female , Cushing Syndrome/diagnostic imaging , Cushing Syndrome/pathology , Adrenal Gland Neoplasms/complications , Adrenal Gland Neoplasms/diagnostic imaging , Adrenal Gland Neoplasms/pathology , Intra-Abdominal Fat/diagnostic imaging , Intra-Abdominal Fat/pathology , Tomography, X-Ray Computed , Hydrocortisone , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/pathology
5.
Biochem Biophys Res Commun ; 527(4): 1050-1056, 2020 07 05.
Article in English | MEDLINE | ID: mdl-32439160

ABSTRACT

Phospholipids are distributed asymmetrically in the plasma membrane (PM) of mammalian cells. Phosphatidylinositol (PI) and its phosphorylated forms are primarily located in the inner leaflet of the PM. Among them, phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is a well-known substrate for phospholipase C (PLC) or phosphoinositide-3 kinase, and is also a regulator for the actin cytoskeleton or ion channels. Although functions of PI(4,5)P2 in the inner leaflet are well characterized, those in the outer leaflet are poorly understood. Here, PI(4,5)P2 was detected in the cell surface of non-permeabilized cells by anti-PI(4,5)P2 antibodies and the pleckstrin-homology (PH) domain of PLCδ1 that specifically binds PI(4,5)P2. Cell surface PI(4,5)P2 signal was universally detected in various cell lines and freshly isolated mouse bone marrow cells and showed a punctate pattern in a cholesterol, sphingomyelin, and actin polymerization-dependent manner. Furthermore, blocking cell surface PI(4,5)P2 by the addition of anti-PI(4,5)P2 antibody or the PH domain of PLCδ1 inhibited cell attachment, spreading, and migration. Taken together, these results indicate a unique localization of PI(4,5)P2 in the outer leaflet that may have a crucial role in cell attachment, spreading, and migration.


Subject(s)
Cell Adhesion , Cell Membrane/metabolism , Cell Movement , Phosphatidylinositol 4,5-Diphosphate/metabolism , Actins/metabolism , Cell Line , Cholesterol/metabolism , Humans , Phosphatidylinositol 4,5-Diphosphate/analysis , Pleckstrin Homology Domains , Sphingomyelins/metabolism , Type C Phospholipases/analysis , Type C Phospholipases/metabolism
6.
Endocr J ; 67(1): 31-35, 2020 Jan 28.
Article in English | MEDLINE | ID: mdl-31527321

ABSTRACT

We report a case of a 47-year-old woman with hypercalcemia 6 months after discontinuation of denosumab. She underwent right mastectomy for breast cancer and had received aromatase inhibitor and denosumab therapy for 5 years. Thirst, appetite loss, and bilateral ankle pain began few months after cessation of denosumab. She was admitted to the hospital for hypercalcemia and hyperthyroidism 6 months after the last dose of denosumab. Laboratory investigations revealed hypercalcemia, normophosphatemia, normal renal function, and elevated levels of fibroblast growth factor 23 (FGF-23). Serum tartrate-resistant acid phosphatase 5b and urine N-terminal cross-linked telopeptide of type I collagen were both elevated, and bone scintigraphy revealed increase of whole bone uptake. Radiological examinations showed no recurrence of breast cancer or tumors that secrete intact PTH or FGF-23. Hypercalcemia, which lasted for 1 month, was refractory to discontinuation of the aromatase inhibitor, normalization of thyroid hormone levels, saline hydration, and calcitonin administration, but was effectively treated with zoledronic acid. Abnormal uptake on bone scintigraphy and ankle pain both resolved a few months after treatment, and hypercalcemia has not recurred in the ensuing 2 years. In conclusion, we found elevated levels of circulating FGF-23 with hypercalcemia following the discontinuation of denosumab. FGF-23 might be a surrogate marker for massive bone resorption triggered by discontinuation of long-term denosumab treatment.


Subject(s)
Aromatase Inhibitors/therapeutic use , Bone Density Conservation Agents/therapeutic use , Bone Neoplasms/prevention & control , Bone Resorption/blood , Breast Neoplasms/drug therapy , Denosumab/therapeutic use , Deprescriptions , Hypercalcemia/blood , Ankle , Anorexia/etiology , Anorexia/physiopathology , Antithyroid Agents/therapeutic use , Arthralgia/etiology , Arthralgia/physiopathology , Bone Neoplasms/secondary , Bone Resorption/drug therapy , Bone Resorption/etiology , Bone Resorption/physiopathology , Collagen Type I/urine , Female , Fibroblast Growth Factor-23 , Fibroblast Growth Factors/blood , Graves Disease/diagnosis , Graves Disease/drug therapy , Humans , Hypercalcemia/drug therapy , Hypercalcemia/etiology , Hypercalcemia/physiopathology , Methimazole/therapeutic use , Middle Aged , Parathyroid Hormone/blood , Peptides/urine , Potassium Iodide/therapeutic use , Radionuclide Imaging , Tartrate-Resistant Acid Phosphatase/blood , Thirst , Zoledronic Acid/therapeutic use
7.
Biochem Biophys Res Commun ; 495(2): 1942-1947, 2018 01 08.
Article in English | MEDLINE | ID: mdl-29247652

ABSTRACT

RhoA is a member of Rho family small GTPases that regulates diverse cellular functions. Recent large-scale sequencing studies have identified recurrent somatic mutations of RHOA in diffuse-type gastric carcinoma (DGC), indicating that RHOA is a driver of DGC. In this study, we investigated the possible abnormalities of RHOA in a panel of gastric carcinoma (GC) cell lines. Pulldown assay and immunoblot analysis showed that the activity and expression of RhoA were detectable in all GC cell lines tested, except for two DGC cell lines, HSC-59 and GSU. RHOA coding region sequencing revealed that aberrant alternative splicing of RHOA occurred in these cell lines. Quantitative real-time PCR analysis showed that the expression of wild-type RHOA was nearly undetectable, whereas splicing variants were almost exclusively expressed in HSC-59 and GSU cell lines. However, the expression levels of RHOA splicing variants were very low and the corresponding proteins were not detected by immunoblotting. Moreover, the splicing isoforms of RhoA protein were neither efficiently expressed nor activated even if ectopically expressed in cells. These results indicate that aberrant alternative splicing of RHOA results in the loss of its activity and expression in DGC cells.


Subject(s)
Alternative Splicing/genetics , Gene Expression Regulation, Neoplastic/genetics , Protein Isoforms/genetics , Stomach Neoplasms/enzymology , Stomach Neoplasms/genetics , rhoA GTP-Binding Protein/genetics , Cell Line, Tumor , Enzyme Activation/genetics , Humans , Mutation/genetics
8.
Biochem Biophys Res Commun ; 495(1): 1292-1299, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29162448

ABSTRACT

Development of resistance against temozolomide (TMZ) in glioblastoma (GBM) after continuous treatment with TMZ is one of the critical problems in clinical GBM therapy. Intracellular cholesterol regulates cancer cell biology, but whether intracellular cholesterol is involved in TMZ resistance of GBM cells remains unclear. The involvement of intracellular cholesterol in acquired resistance against TMZ in GBM cells was investigated. Intracellular cholesterol levels were measured in human U251 MG cells with acquired TMZ resistance (U251-R cells) and TMZ-sensitive control U251 MG cells (U251-Con cells), and found that the intracellular cholesterol level was significantly lower in U251-R cells than in U251-Con cells. In addition, treatment by intracellular cholesterol remover, methyl-beta cyclodextrin (MßCD), or intracellular cholesterol inducer, soluble cholesterol (Chol), regulated TMZ-induced U251-Con cell death in line with changes in intracellular cholesterol level. Involvement of death receptor 5 (DR5), a death receptor localized in the plasma membrane, was evaluated. TMZ without or with MßCD and/or Chol caused accumulation of DR5 into the plasma membrane lipid raft and formed a complex with caspase-8, an extrinsic caspase cascade inducer, reflected in the induction of cell death. In addition, treatment with caspase-8 inhibitor or knockdown of DR5 dramatically suppressed U251-Con cell death induced by combination treatment with TMZ, MßCD, and Chol. Combined treatment of Chol with TMZ reversed the TMZ resistance of U251-R cells and another GBM cell model with acquired TMZ resistance, whereas clinical antihypercholesterolemia agents at physiological concentrations suppressed TMZ-induced cell death of U251-Con cells. These findings suggest that intracellular cholesterol level affects TMZ treatment of GBM mediated via a DR5-caspase-8 mechanism.


Subject(s)
Caspase 8/metabolism , Cholesterol/metabolism , Dacarbazine/analogs & derivatives , Glioblastoma/drug therapy , Glioblastoma/metabolism , Membrane Microdomains/metabolism , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism , Antineoplastic Agents, Alkylating/administration & dosage , Apoptosis/drug effects , Cell Line, Tumor , Dacarbazine/administration & dosage , Dose-Response Relationship, Drug , Drug Resistance, Neoplasm , Glioblastoma/pathology , Humans , Intracellular Fluid/metabolism , Membrane Microdomains/drug effects , Temozolomide
10.
Cancer Sci ; 108(5): 1049-1057, 2017 May.
Article in English | MEDLINE | ID: mdl-28256037

ABSTRACT

CUB domain-containing protein-1 (CDCP1) is a trans-membrane protein predominantly expressed in various cancer cells and involved in tumor progression. CDCP1 is phosphorylated at tyrosine residues in the intracellular domain by Src family kinases and recruits PKCδ to the plasma membrane through tyrosine phosphorylation-dependent association with the C2 domain of PKCδ, which in turn induces a survival signal in an anchorage-independent condition. In this study, we used our cell-free screening system to identify a small compound, glycoconjugated palladium complex (Pd-Oqn), which significantly inhibited the interaction between the C2 domain of PKCδ and phosphorylated CDCP1. Immunoprecipitation assays demonstrated that Pd-Oqn hindered the intercellular interaction of phosphorylated CDCP1 with PKCδ and also suppressed the phosphorylation of PKCδ but not that of ERK or AKT. In addition, Pd-Oqn inhibited the colony formation of gastric adenocarcinoma 44As3 cells in soft agar as well as their invasion. In mouse models, Pd-Oqn markedly reduced the peritoneal dissemination of gastric adenocarcinoma cells and the tumor growth of pancreatic cancer orthotopic xenografts. These results suggest that the novel compound Pd-Oqn reduces tumor metastasis and growth by inhibiting the association between CDCP1 and PKCδ, thus potentially representing a promising candidate among therapeutic reagents targeting protein-protein interaction.


Subject(s)
Cell Proliferation/drug effects , Neoplasm Metastasis/drug therapy , Neoplasm Proteins/metabolism , Protein Kinase C-delta/metabolism , Small Molecule Libraries/pharmacology , A549 Cells , Animals , Cell Adhesion/drug effects , Cell Line , Cell Line, Tumor , Cell Movement/drug effects , HEK293 Cells , Humans , MAP Kinase Signaling System/drug effects , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects
11.
Biochem Biophys Res Commun ; 468(1-2): 240-7, 2015.
Article in English | MEDLINE | ID: mdl-26518652

ABSTRACT

Temozolomide (TMZ) is one of the few effective anticancer agents against gliomas. However, acquisition of TMZ resistance or adaptation by gliomas is currently a crucial problem, especially increased invasiveness which is critical for the determination of clinical prognosis. This study investigated the molecular regulatory mechanisms of TMZ resistance in gliomas involved in invasiveness, particularly invadopodia formation, a molecular complex formed at the invasive front to cause extracellular matrix degradation during cellular local invasion. The TMZ-resistant clone of the U343 MG human glioma cell line (U343-R cells) was established. U343-R cells demonstrated higher invadopodia formation compared with U343 cells without TMZ resistance (U343-Con cells). Immunoblot analysis of DNA damage-related mitogen-activated protein kinase signals found increased phosphorylation of c-Jun terminal kinase (JNK) and higher activation of its downstream signaling in U343-R cells compared with U343-Con cells. Treatment of U343-R cells with specific inhibitors of JNK or siRNA targeting JNK suppressed up-regulation of invadopodia formation. In addition, paxillin, one of the known JNK effectors which is phosphorylated and affects cell migration, was phosphorylated at serine 178 in JNK activity-dependent manner. Expression of paxillin with mutation of the serine 178 phosphorylation site in U343-R cells blocked invadopodia formation. The present findings suggest that increased formation of invadopodia in U343-R cells is mediated by hyperactivation of JNK-paxillin signaling, and both JNK and paxillin might become targets of novel therapies against TMZ-resistant gliomas.


Subject(s)
Antineoplastic Agents, Alkylating/pharmacology , Dacarbazine/analogs & derivatives , Drug Resistance, Neoplasm , Glioma/drug therapy , JNK Mitogen-Activated Protein Kinases/metabolism , Paxillin/metabolism , Podosomes/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Dacarbazine/pharmacology , Glioma/metabolism , Glioma/pathology , Humans , Phosphorylation/drug effects , Podosomes/metabolism , Podosomes/pathology , Signal Transduction/drug effects , Temozolomide
12.
Biochem Biophys Res Commun ; 457(2): 148-53, 2015 Feb 06.
Article in English | MEDLINE | ID: mdl-25529453

ABSTRACT

Neuroendocrine regulatory peptides (NERP-1 and -2) are novel amidated peptides derived from VGF, a polypeptide secreted from neurons and endocrine cells through a regulated pathway. Dr. Nakazato Masamitsu reported that NERP-1 and -2 may have a local modulator function on the human endocrine system, and clearly showed expression of NERP-1 and -2 in human pancreas islets. Based on these data, we investigated the alteration of insulin secretion, insulin granule-related protein, and pancreas-specific transcription factors in response to NERPs expression. We confirmed the expression of NERP-1 and -2 in the pancreas of a human diabetes patient, in addition to diabetic animal models. When INS1 cells and primary rat islets were incubated with 10nM NERPs for 3 days, glucose-stimulated insulin secretion levels were blunted by NERP-1 and -2. The number of insulin granules released from the readily releasable pool, which is associated with the first phase of glucose-stimulated insulin release, was decreased by NERP-1 and -2. Insulin granule-related proteins and mRNAs were down-regulated by NERP-2 treatment. NERP-2 decreased the expression of BETA2/NeuroD and insulin and controlled the nucleo-cytoplasmic translocation of FOXO1 and Pdx-1. We observed that NERP-2 levels were dramatically increased in diabetic pancreas. In conclusion, NERP-2 may play an important role in insulin secretion through the regulation of insulin secretory granules and ß-cell transcription factors. In addition, NERP-2 expression is increased in diabetic conditions. Therefore, we suggest that NERPs may be potent endogenous suppressors of glucose-dependent insulin secretion.


Subject(s)
Gene Expression Regulation , Insulin-Secreting Cells/metabolism , Insulin/metabolism , Nerve Tissue Proteins/metabolism , Animals , Diabetes Mellitus/metabolism , Diabetes Mellitus/pathology , Humans , Insulin Secretion , Insulin-Secreting Cells/drug effects , Rats, Sprague-Dawley , Secretory Vesicles/metabolism , Transcription Factors/metabolism
13.
Cancer Sci ; 105(5): 528-36, 2014 May.
Article in English | MEDLINE | ID: mdl-24612061

ABSTRACT

Diffuse-type gastric carcinomas (DGC) exhibit more aggressive progression and poorer prognosis than intestinal-type and other gastric carcinomas. To identify potential therapeutic targets, we examined protein tyrosine phosphorylation in a panel of DGC and other gastric cancer cell lines. Protein tyrosine phosphorylation was significantly enhanced or altered in DGC cell lines compared with that in other gastric cancer cell lines. Affinity purification and mass spectrometry analysis of tyrosine-phosphorylated proteins identified Met as a protein that is preferentially expressed and phosphorylated in DGC cell lines. Unexpectedly, Met inhibitors blocked cell growth, Met downstream signaling and peritoneal dissemination in vivo in only a subset of cell lines that exhibited remarkable overexpression of Met. Likewise, only cell lines with overexpression of fibroblast growth factor receptor 2 (FGFR2) or phosphorylation of FRS2 were sensitive to an FGFR2 inhibitor. A Src inhibitor saracatinib impaired growth in cell lines that are insensitive to both Met and FGFR2 inhibitors. Saracatinib also effectively impaired peritoneal dissemination of Met-independent and FGFR2-independent SGC cells. Moreover, DGC cell lines exhibited nearly mutually exclusive susceptibility to Met, FGFR and Src inhibitors. These results suggest that DGC have distinct sensitivities to molecular target drugs and that targeting Src is beneficial in the treatment of DGC insensitive to Met and FGFR inhibition.


Subject(s)
Antineoplastic Agents/pharmacology , Benzodioxoles/pharmacology , Drug Resistance, Neoplasm , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-met/antagonists & inhibitors , Quinazolines/pharmacology , Receptor, Fibroblast Growth Factor, Type 2/antagonists & inhibitors , Stomach Neoplasms/drug therapy , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Molecular Targeted Therapy , Peritoneum/cytology , Peritoneum/drug effects , Phosphorylation , Proto-Oncogene Proteins c-met/metabolism , Receptor, Fibroblast Growth Factor, Type 2/metabolism , Signal Transduction/drug effects , src-Family Kinases/antagonists & inhibitors
14.
J Cell Sci ; 125(Pt 21): 4979-84, 2012 Nov 01.
Article in English | MEDLINE | ID: mdl-22946045

ABSTRACT

Highly selective nucleocytoplasmic molecular transport is critical to eukaryotic cells, which is illustrated by size-filtering diffusion and karyopherin-mediated passage mechanisms. However, a considerable number of large proteins without nuclear localization signals are localized to the nucleus. In this paper, we provide evidence for the spontaneous migration of large proteins in a karyopherin-independent manner. Time-lapse observation of a nuclear transport assay revealed that several large molecules spontaneously and independently pass through the nuclear pore complex (NPC). The amphiphilic motifs were sufficient to overcome the selectivity barrier of the NPC. Furthermore, the amphiphilic property of these proteins enables altered local conformation in hydrophobic solutions so that elevated surface hydrophobicity facilitates passage through the nuclear pore. The molecular dynamics simulation revealed the conformational change of the amphiphilic structure that exposes the hydrophobic amino acid residues to the outer surface in a hydrophobic solution. These results contribute to the understanding of nucleocytoplasmic molecular sorting and the nature of the permeability barrier.


Subject(s)
Karyopherins/physiology , Nuclear Pore/metabolism , Actinin/chemistry , Actinin/metabolism , Active Transport, Cell Nucleus , Animals , Cell Nucleus/metabolism , Green Fluorescent Proteins/chemistry , Green Fluorescent Proteins/metabolism , HeLa Cells , Humans , Hydrophobic and Hydrophilic Interactions , Kinetics , Molecular Dynamics Simulation , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Protein Structure, Secondary , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Sf9 Cells , Spectrin/chemistry , Spectrin/metabolism , Spodoptera , Surface Properties , Time-Lapse Imaging , beta Catenin/chemistry , beta Catenin/metabolism
15.
J Cell Sci ; 125(Pt 3): 724-34, 2012 Feb 01.
Article in English | MEDLINE | ID: mdl-22389406

ABSTRACT

Invadopodia are proteolytic membrane protrusions formed by highly invasive cancer cells, commonly observed on substrate(s) mimicking extracellular matrix. Although invadopodia are proposed to have roles in cancer invasion and metastasis, direct evidence has not been available. We previously reported that neural Wiskott-Aldrich syndrome protein (N-WASP), a member of WASP family proteins that regulate reorganization of the actin cytoskeleton, is an essential component of invadopodia. Here, we report that N-WASP-mediated invadopodium formation is essential in breast cancer invasion, intravasation and lung metastasis. We established stable cell lines based on MTLn3 rat mammary adenocarcinoma cells that either overexpressed a dominant-negative (DN) N-WASP construct or in which N-WASP expression was silenced by a pSuper N-WASP shRNA. Both the N-WASP shRNA and DN N-WASP cells showed a markedly decreased ability to form invadopodia and degrade extracellular matrix. In addition, formation of invadopodia in primary tumors and collagen I degradation were reduced in the areas of invasion (collagen-rich areas in the invasive edge of the tumor) and in the areas of intravasation (blood-vessel-rich areas). Our results suggest that tumor cells in vivo that have a decreased activity of N-WASP also have a reduced ability to form invadopodia, migrate, invade, intravasate and disseminate to lung compared with tumor cells with parental N-WASP levels.


Subject(s)
Lung Neoplasms/metabolism , Lung Neoplasms/secondary , Mammary Neoplasms, Experimental/metabolism , Mammary Neoplasms, Experimental/pathology , Neoplasm Invasiveness/physiopathology , Wiskott-Aldrich Syndrome Protein, Neuronal/metabolism , Adenocarcinoma/genetics , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Adenocarcinoma/secondary , Animals , Base Sequence , Cell Line, Tumor , Female , Gene Knockdown Techniques , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mammary Neoplasms, Experimental/genetics , Matrix Metalloproteinases/metabolism , Mice , Mice, SCID , Neoplasm Invasiveness/genetics , Neoplasm Invasiveness/pathology , RNA, Small Interfering/genetics , Rats , Rats, Inbred F344 , Wiskott-Aldrich Syndrome Protein, Neuronal/antagonists & inhibitors , Wiskott-Aldrich Syndrome Protein, Neuronal/genetics
16.
Cancers (Basel) ; 16(9)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38730588

ABSTRACT

Cancer invasion is a requisite for the most malignant progression of cancer, that is, metastasis. The mechanisms of cancer invasion were originally studied using in vitro cell culture systems, in which cancer cells were cultured using artificial extracellular matrices (ECMs). However, conventional culture systems do not precisely recapitulate in vivo cancer invasion because the phenotypes of cancer cells in tumor tissues are strongly affected by the tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs) are the most abundant cell type in the TME and accelerate cancer progression through invasion, metastasis, therapy resistance, and immune suppression. Thus, the reciprocal interactions between CAFs and cancer cells have been extensively studied, leading to the identification of factors that mediate cellular interactions, such as growth factors, cytokines, and extracellular vesicles. In addition, the importance of direct heterocellular adhesion between cancer cells and CAFs in cancer progression has recently been elucidated. In particular, CAFs are directly associated with cancer cells, allowing them to invade the ECM and metastasize to distant organs. In this review, we summarize the recent progress in understanding the molecular and cellular mechanisms of the direct heterocellular interaction in CAF-led cancer invasion and metastasis, with an emphasis on gastric cancer.

17.
Diabetol Int ; 15(3): 439-446, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39101182

ABSTRACT

Aim: Education on insulin self-injection techniques is important for good glycemic control, but its effectiveness in some elderly patients is limited due to loss of cognitive function and impaired activities of daily living. We hypothesized that classification using the Dementia Assessment Sheet for Community-based Integrated Care System 8-items (DASC-8) would help identify elderly patients with diabetes who effectively learn self-injection techniques. Methods: Diabetes patients aged ≥ 65 years who used a self-injection insulin pen were administered the DASC-8 and a questionnaire to evaluate insulin self-injection techniques, and then received technical education. The questionnaire was administered again 4 months later, and patients were classified into the education-effective and education-ineffective groups. The achievement of HbA1c targets defined for each patient according to guidelines based on DASC-8 category was examined over 12 months. Results: 76 Japanese patients (median age 72.0 years and 53.9% female) with DASC-8 categories I (n = 55), II (n = 13), and III (n = 8) were enrolled. In the education-effective group, the percentage of patients in category I was significantly higher than that of patients in category II or III (92.0% to 23.8%, P < 0.001). Category I was independently associated with education effectiveness (odds ratio 14.50, 95% confidence interval: 2.110-100.0, P = 0.007). Category I patients in the education-effective group showed significantly improved achievement of target HbA1c from baseline to the 12th month (from 27.6% to 62.1%, P = 0.008). Conclusions: The DASC-8 was a useful indicator for identifying elderly patients who would benefit from education on self-injection techniques. Supplementary Information: The online version contains supplementary material available at 10.1007/s13340-024-00710-z.

18.
ACS Synth Biol ; 12(2): 572-582, 2023 02 17.
Article in English | MEDLINE | ID: mdl-36734676

ABSTRACT

Enzyme engineering using machine learning has been developed in recent years. However, to obtain a large amount of data on enzyme activities for training data, it is necessary to develop a high-throughput and accurate method for evaluating enzyme activities. Here, we examined whether a biosensor-based enzyme engineering method can be applied to machine learning. As a model experiment, we aimed to modify the substrate specificity of XylM, a rate-determining enzyme in a multistep oxidation reaction catalyzed by XylMABC in Pseudomonas putida. XylMABC naturally converts toluene and xylene to benzoic acid and toluic acid, respectively. We aimed to engineer XylM to improve its conversion efficiency to a non-native substrate, 2,6-xylenol. Wild-type XylMABC slightly converted 2,6-xylenol to 3-methylsalicylic acid, which is the ligand of the transcriptional regulator XylS in P. putida. By locating a fluorescent protein gene under the control of the Pm promoter to which XylS binds, a XylS-producing Escherichia coli strain showed higher fluorescence intensity in a 3-methylsalicylic acid concentration-dependent manner. We evaluated the 3-methylsalicylic acid productivity of XylM variants using the fluorescence intensity of the sensor strain as an indicator. The obtained data provided the training data for machine learning for the directed evolution of XylM. Two cycles of machine learning-assisted directed evolution resulted in the acquisition of XylM-D140E-V144K-F243L-N244S with 15 times higher productivity than wild-type XylM. These results demonstrate that an indirect enzyme activity evaluation method using biosensors is sufficiently quantitative and high-throughput to be used as training data for machine learning. The findings expand the versatility of machine learning in enzyme engineering.


Subject(s)
Biosensing Techniques , Pseudomonas putida , Toluene/metabolism , Substrate Specificity , Plasmids , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Pseudomonas putida/genetics , Pseudomonas putida/metabolism , Machine Learning
19.
J Neurosurg Case Lessons ; 6(10)2023 Sep 04.
Article in English | MEDLINE | ID: mdl-37728240

ABSTRACT

BACKGROUND: Ameloblastic carcinoma (AC) is a rare odontogenic carcinoma with histological features resembling ameloblastoma. Metastasis to distant organs and direct expansion into the skull base structures are associated with a poor clinical outcome. This rare case of AC metastasis to the pituitary gland presented without local recurrence at the primary focus of the maxilla. OBSERVATIONS: A 47-year-old man had a 2-year history of AC in the right maxilla. Computed tomography for his regular checkup incidentally demonstrated pituitary tumor, rapidly growing over 2 months. He presented with the recent onset of panhypopituitarism and visual field defect. Magnetic resonance imaging showed a large, irregularly shaped intrasellar and suprasellar lesion with chiasmal compression. Endoscopic endonasal transsphenoidal surgery was performed for decompression of the optic apparatus to avoid intracranial spread. Histopathology confirmed metastatic AC, and a genetic panel test confirmed BRAF V600E mutation. Stereotactic radiotherapy (SRT) with the CyberKnife system was administered to the residual tumor. Remarkable tumor shrinkage was obtained, and panhypopituitarism was resolved 12 months later. LESSONS: A multidisciplinary treatment strategy including maximal safe resection to avoid dissemination in combination with SRT may be crucial for local control with the preservation of pituitary and visual functions in patients with solitary pituitary metastatic AC.

20.
Diabetes Ther ; 14(3): 569-579, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36732433

ABSTRACT

INTRODUCTION: Endothelial dysfunction is a risk factor for cardiovascular disease in patients with diabetes. We hypothesized that imeglimin, a novel oral hypoglycemic agent, would improve endothelial function. METHODS: In this study, imeglimin was administered to patients with type 2 diabetes and HbA1c ≥ 6.5% who were not receiving insulin therapy. A meal tolerance test (592 kcal, glucose 75.0 g, fat 28.5 g) was performed before and 3 months after administration, and endothelial function, blood glucose, insulin, glucagon, and triglycerides were evaluated. Endothelial function was assessed by flow-mediated dilation (FMD). RESULTS: Twelve patients (50% male) with a median age of 55.5 years old (interquartile range [IQR] 51.3-66.0) were enrolled. Fasting FMD did not differ before or 3 months after imeglimin administration (from 6.1 [3.9-8.5] to 6.6 [3.9-9.0], p = 0.092), but 2 h postprandial FMD was significantly improved 3 months after imeglimin administration (from 2.3 [1.9-3.4] to 2.9 [2.4-4.7], p = 0.013). In terms of the glucose profile, imeglimin administration significantly improved HbA1c (from 7.2 ± 0.6% to 6.9 ± 0.6%, p = 0.007), fasting glucose (from 138 ± 19 mg/dL to 128 ± 20 mg/dL, p = 0.020), and 2 h postprandial glucose (from 251 ± 47 mg/dL to 215 ± 68 mg/dL, p = 0.035). The change in 2 h postprandial FMD between before and 3 months after imeglimin administration (Δ2 h postprandial FMD) was negatively correlated with Δ2 h postprandial glucose (r = - 0.653, p = 0.021) in a univariate correlation coefficient analysis. Both patients with and without decreased postprandial glucose 3 months after imeglimin administration had improved postprandial FMD. CONCLUSION: In this small study, imeglimin administration improved 2 h postprandial FMD. Both glycemic control-dependent and -independent mechanisms might contribute to improved endothelial function. TRIAL REGISTRATION: This research was registered in the University Hospital Medical Information Network (UMIN, UMIN000046311).

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