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Leukemia is a complex disease shaped by the intricate interplay of genetic and environmental factors. Given our preliminary data showing different leukemia incidence in genetically homogenous AKR mice harboring the spontaneous leukemia-inducing mutation Rmcfs, we sought to unravel the role of metabolites and gut microbiota in the leukemia penetrance. Our metabolomic analysis revealed distinct serum metabolite profiles between mice that developed leukemia and those that did not. We discovered that linoleic acid (LA), an essential ω-6 polyunsaturated fatty acid, was significantly decreased in the leukemia group, with the lower levels observed starting from 25 weeks before the onset. A predictive model based on LA levels demonstrated high accuracy in predicting leukemia development (area under curve 0.82). In vitro experiment confirmed LA's cytotoxic effects against leukemia cells, and in vivo study showed that a diet enriched with LA prolonged survival in AKR mice. Furthermore, gut microbiome analysis identified specific Lachnospiraceae species, that affect host lipid metabolism, are exclusively present in the leukemia group, suggesting their potential influence on LA metabolism and leukemia development. These findings shed light on the complex relationship between metabolites, gut microbiota, and leukemia development, providing valuable insights into the role of non-genetic factors in leukemia penetrance and potential strategies for leukemia prevention., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Human mesenchymal stem cells (MSCs) are known to have anti-inflammatory and immunomodulatory functions; thus, several MSC products have been applied as cell therapy in clinical trials worldwide. Recent studies have demonstrated that MSC spheroids have superior anti-inflammatory and immunomodulatory functions to a single cell suspension. Current methods to prepare MSC spheroids include hanging drop, concave microwell aggregation, spinner flask, and gravity circulation. However, all these methods have limitations such as low scalability, easy cell clumping, low viability, and irregular size distribution. Here, we present a nano-patterned culture plasticware named PAMcell™ 3D plate to overcome these limitations. Nano-sized silica particles (700 nm) coated with RGD peptide were arrayed into fusiform onto the PLGA film. This uniform array enabled the seeded MSCs to grow only on the silica particles, forming uniform-sized semi-spheroids within 48 h. These MSC spheroids have been shown to have enhanced stemness, anti-inflammatory, and immunomodulatory functions, as revealed by the increased expression of stem cell markers (Oct4, Sox2, and Nanog), anti-inflammatory (IL-10, TSG6, and IDO), and immunomodulatory molecules (HGF, VEGF, CXCR4) both at mRNA and protein expression levels. Furthermore, these MSC spheroids demonstrated an increased palliative effect on glycemic control in a multiple low-dose streptozotocin-induced diabetes model compared with the same number of MSC single cell suspensions. Taken together, this study presents a new method to produce uniform-sized MSC spheroids with enhanced anti-inflammatory and immunomodulatory functions in vitro and in vivo., Competing Interests: Declaration of competing interest All authors have no conflict of interest., (Copyright © 2021 Elsevier Inc. All rights reserved.)

High mobility group (HMGB1) is an alarmin known to be harmful to pancreatic beta cells and associated with diabetes mellitus pathogenesis and pancreatic islet graft failure. It has been long thought that the suppression of HMGB1 molecule is beneficial to the beta cells. However, recent studies have indicated that cytoplasmic HMGB1 (cHMGB1) could function as a modulator to relieve cells from apoptotic stress by autophagy induction. Particularly, pancreatic beta cells have been known to utilize the autophagy-to-apoptosis switch when exposed to hypoxia or lipotoxicity. This study aimed to investigate the beta cells under hypoxic and lipotoxic stress while utilizing a small molecule inhibitor of HMGB1, inflachromene (ICM) which can suppress cHMGB1 accumulation. It was revealed that under cellular stress, blockade of cHMGB1 accumulation decreased the viability of islet grafts, primary islets and MIN6 cells. MIN6 cells under cHMGB1 blockade along with lipotoxic stress showed decreased autophagic flux and increased apoptosis. Moreover, cHMGB1 blockade in HFD-fed mice produced unfavorable outcomes on their glucose tolerance. In sum, these results suggested the role of cHMGB1 within beta cell autophagy/apoptosis checkpoint. Given the importance of autophagy in beta cells under apoptotic stresses, this study might provide further insights regarding HMGB1 and diabetes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Inc.)

Islet cell dysfunction in type 2 diabetes is primarily attributed to the increased apoptosis of pancreatic beta cells. Silk fibroin hydrolysate (SFH) has an effect on blood in type 2 diabetes model mice (C57BL/KsJ-db/db). However, its exact mechanism is unknown. The type 2 diabetes model mice were randomly divided into non-diabetic mice (ND), diabetic mice (DB), and diabetic mice treated with silk fibroin hydrolysate (DB-SFH). The results showed that SFH significantly decreased fasting blood glucose and hemoglobin A1c (HbA1c). The oral glucose tolerance and insulin tolerance were significantly improved in the DB-SFH group. The DB-SFH group exhibited increased superoxide dismutase (SOD) activity in the plasma, as well as increased Mn-SOD and CuZn-SOD activities in the pancreatic islets. Furthermore, the pancreatic islet cells' death was decreased in the DB-SFH group. In the DB-SFH group, the protein expression of caspase-3 was significantly decreased compared with the DB group. The expression of the Nkx6.1 and Pdx1 proteins were increased in the DB-SFH group. The results suggest that SFH prevents the degeneration of pancreatic islets via increasing SOD while hyperglycemia is alleviated by maintaining beta cell mass in type 2 diabetes model mice., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Cancer stem cells (CSCs) are a subpopulation of cancer cells and have been known to create cancer reoccurrence during cancer therapy due to their stem cell-like characteristics. However, exact target to control the CSC has not been fully established. Here, we enriched CD44 High population of MDA-MB-231 cells by CD44 antibody as a CSC marker. By Phospho Antibody Array, CD44 High population of MDA-MB-231 cells reveals Feline sarcoma-related tyrosine kinase (FER) protein was highly activated. When FER siRNA and low molecular weight protamine (LMWP) as cell penetrating peptides are applied to this population, cancer migration and colony forming ability are inhibited. Moreover, silencing FER using FER siRNA and LMWP conjugates enhances anti-metastasis related factors including E-cadherin, p75 and p63. Taken together, FER is a new marker for targeting breast CSCs and peptide-mediated siRNA method could be an effective and safe way of delivery and be a new therapeutic strategy for targeting breast cancer., (Copyright © 2017. Published by Elsevier Inc.)

Sclerostin, encoded by the Sost gene, is mainly produced by osteocytes in bone and antagonizes the Wnt/β-catenin signaling pathway, which is a requisite for bone formation. Currently, human anti-sclerostin antibodies are being tested in phase III clinical trials. In addition, serum sclerostin levels are reported to be associated with bone mineral density and fracture risk in normal individuals; however, the correlation between serum sclerostin and bone mass remains controversial. To study the effects of the continuous exposure of exogenous sclerostin on bone, a ΦC31 integrase system, which has the characteristics of site-specificity and efficiency, was applied for the delivery of the Sost gene in this study. We injected Sost-attB plasmid with or without ΦC31 integrase plasmid into the mouse tail vein using a hydrodynamic-based method. The site-specific integration of the Sost gene into the mouse genome was confirmed by examining a pseudo-attP site on the hepatic genomic DNA. Sclerostin was expressed in the hepatocytes, secreted into the blood flow, and maintained at high concentrations in the mice with both Sost-attB plasmid and ΦC31 integrase plasmid injections, which was observed by serial measurement. Moreover, the mice with long-term high levels of serum sclerostin showed trabecular bone loss on micro-CT analysis. Peripheral B cell populations were not affected. Our results suggested that sclerostin could be expressed in the liver and sustained successfully at high levels in the blood by using the ΦC31 integrase system, leading to trabecular bone loss. These findings may help to further ascertain the effects of sclerostin introduced exogenously on the skeleton., (Copyright © 2016 Elsevier Inc. All rights reserved.)

It is well known that interactions between epithelial components and mesenchymal components are essential for tooth development. Therefore, it has been postulated that both types of stem cells might be involved in the regeneration of dental hard tissues. Recently, mesenchymal dental pulp stem cells that have odontogenic potential were identified from human dental pulp. However, the existence of epithelial cells has never been reported in human dental pulp. In the present study, we isolated and characterized epithelial cell-like cells from human deciduous dental pulp. They had characteristic epithelial morphology and expressed epithelial markers. Moreover, they expressed epithelial stem cell-related genes such as ABCG2, Bmi-1, DeltaNp63, and p75. Taken together, our findings suggest that epithelial stem cell-like cells might exist in human deciduous dental pulp and might play a role as an epithelial component for the repair or regeneration of teeth.

The cancer stem cell theory suggests that chemoresistance and recurrence of tumors are often due to the similarity of stem cell properties between normal and cancer cells. Adult T-cell leukemia/lymphoma (ATLL) has poor prognosis, suggesting that ATLL cells possess common stem cell properties. We analyzed side population (SP), a characteristic stem cell phenotype, and CD markers in ATLL cell lines. We found that several lines contained SP with expressions of some hematopoietic stem cell markers. On the other hand, treatment with interferon (IFN)-alpha is sometimes effective in ATLL, particularly combined with other drugs. We examined its effect on ATLL cells and found that IFN-alpha significantly reduced the SP proportion. Moreover, CD25-positive cells and phosphorylation of STAT1/5 and ERK were upregulated during this process. These data suggest that their stem cell properties render ATLL cells therapy-resistant, and IFN-alpha exerts its clinical effect through a reduction of the SP cell population.

Three proteases were identified in the excretory/secretory proteins (ESP) from Toxoplasma gondii by the gelatin acrylamide gel electrophoresis (GAGE), of which the molecular masses were 80, 70, and 42 kDa. One of the proteases with 42 kDa was reactive to a monoclonal antibody (mAb), Tg786 clone, which was localized in the rhoptry of T. gondii by immunohistochemistry. The protease was maximally active at the pH range between 7.5 and 8.5, and was sensitive to inhibition by TPCK and EGTA. The gelatinolytic activity of the protease was dependent on the concentration of calcium ion. The protease was active only in the millimolar ranges of calcium but not in micromolar ranges, implicating that the secretion is critical event for the activation of the protease. The secreted protease was shown to bind to the host cells upon Western blot and immunofluorescence analysis. It is suggested that the protease may target to the plasma membrane of the host cells, which provides appropriate environment for the entry of the parasite into host cells. The mAb (Tg786) of T. gondii also reacted with a protein of the same size and equivalent locality of rhoptry in Neospora caninum, a similar Apicomplexan protozoa, suggesting that secreted protease mediates a common function in the mechanism of entry into host cells., (Copyright 2001 Academic Press.)

Genomic alterations and abnormal expression of the fragile histidine triad (FHIT) gene in gastric carcinomas were examined to determine whether the FHIT gene is actually a frequent target for alteration during gastric carcinogenesis. To correlate DNA and RNA lesions of the FHIT gene with the effect on FHIT protein expression, we have investigated the FHIT gene for loss of heterozygosity (LOH), aberrant transcripts, point mutations, and protein expression in 35 gastric adenocarcinomas. Allelic loss at D3S1300 was detected in 7 of 33 (21%) informative cases. Aberrant transcripts, with deletions and/or insertions, were observed in 20 of 35 (57.1%) cases and resulted from alternative splicing through exon skipping and/or insertion of the FHIT intron 5 sequence or activation of the cryptic splice site. Point mutations were not found in the FHIT coding region but detected in noncoding exon 2, 3, 4, or 5 of eight aberrant transcripts. Significant reduction of FHIT protein expression was observed in 22 of 35 (62.9%) cases. Aberrant FHIT transcription was shown to be associated with loss of FHIT protein expression. However, aberrant FHIT transcripts themselves were not associated with any clinicopathological parameters, such as age, sex, tumor site, or clinical stage. Moreover, there was no association between the presence of LOH at D3S1300 and the expression of aberrant FHIT transcripts. Nevertheless, high frequency of aberrant FHIT transcripts, significant rate of LOH at D3S1300, and altered expression of the FHIT protein indicate that alterations of the FHIT gene can play an important role in gastric carcinogenesis., (Copyright 2001 Academic Press.)

To date, little is known about the molecular mechanisms controlling the regulation of phospholipase C-delta1 (PLC-delta1) gene expression. To understand the mechanisms responsible for the regulation of PLC-delta1 gene expression, the 5'-flanking region of the mouse PLC-delta1 gene was isolated from a mouse genomic DNA library. Primer extension analysis revealed that there is a single transcriptional start site located at 127 bases upstream from the translation start codon in the mouse PLC-delta1 gene. DNA sequence analysis showed that the sequence around the transcriptional start site is very GC-rich and has no TATA or CAAT boxes. Transient expression of a luciferase reporter gene under the control of serially deleted 5'-flanking sequences revealed that the 160-base-pair region from -622 to -462 upstream of the transcriptional start site includes a positive cis-acting element(s) for the efficient expression of the PLC-delta1 gene. Gel retardation analysis suggests that multiple transcription factors bind to separate sites on the promoter region. Based on these results, our study suggests that the minimal essential region located at -622 to +70 is fully sufficient to confer high-level transcriptional activity and contains high-affinity binding elements for multiple transcription factors., (Copyright 2000 Academic Press.)