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Fulltext Immunological history governs human stem cell memory CD4 heterogeneity via the Wnt signaling pathway

Kared H, Tan SW, Lau MC, Chevrier M, Tan C, How W, et al.

Nat Commun, 2020 02 10;11(1):821.
PMID: 32041953 DOI: 10.1038/s41467-020-14442-6

The diversity of the naïve T cell repertoire drives the replenishment potential and capacity of memory T cells to respond to immune challenges. Attrition of the immune system is associated with an increased prevalence of pathologies in aged individuals, but whether stem cell memory T lymphocytes (TSCM) contribute to such attrition is still unclear. Using single cells RNA sequencing and high-dimensional flow cytometry, we demonstrate that TSCM heterogeneity results from differential engagement of Wnt signaling. In humans, aging is associated with the coupled loss of Wnt/β-catenin signature in CD4 TSCM and systemic increase in the levels of Dickkopf-related protein 1, a natural inhibitor of the Wnt/β-catenin pathway. Functional assays support recent thymic emigrants as the precursors of CD4 TSCM. Our data thus hint that reversing TSCM defects by metabolic targeting of the Wnt/β-catenin pathway may be a viable approach to restore and preserve immune homeostasis in the context of immunological history.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism
Fulltext The Effects of Tocotrienol on Bone Peptides in a Rat Model of Osteoporosis Induced by Metabolic Syndrome: The Possible Communication between Bone Cells

Wong SK, Chin KY, Ima-Nirwana S

Int J Environ Res Public Health, 2019 09 09;16(18).
PMID: 31505801 DOI: 10.3390/ijerph16183313

A positive association between metabolic syndrome (MetS) and osteoporosis has been demonstrated in previous animal studies. The mechanisms of MetS in orchestrating the bone remodelling process have traditionally focused on the interactions between mature osteoblasts and osteoclasts, while the role of osteocytes is unexplored. Our earlier studies demonstrated the bone-promoting effects of tocotrienol using a rat model of osteoporosis induced by MetS. This study aimed to investigate the expression of osteocyte-derived peptides in the bone of rats with MetS-induced osteoporosis treated with tocotrienol. Age-matched male Wistar rats (12-week-old; n = 42) were divided into seven experimental groups. Two groups served as the baseline and normal group, respectively. The other five groups were fed with a high-carbohydrate high-fat (HCHF) diet to induce MetS. The five groups of HCHF animals were treated with tocopherol-stripped corn oil (vehicle), annatto tocotrienol (60 and 100 mg/kg), and palm tocotrienol (60 and 100 mg/kg) starting from week 8. At the end of the study, the rats were sacrificed and their right tibias were harvested. Protein was extracted from the metaphyseal region of the proximal right tibia and levels of bone peptides, including osteoprotegerin (OPG), soluble receptor activator of nuclear factor-kappa B ligand (sRANKL), sclerostin (SOST), Dickkopf-related protein 1 (DKK-1), fibroblast growth factor-23 (FGF-23), and parathyroid hormone (PTH), were measured. The vehicle-treated animals displayed higher levels of sRANKL, SOST, DKK-1, FGF-23, and PTH as compared to the normal animals. Oral supplementation of annatto and palm tocotrienol (60 and 100 mg/kg) reduced the levels of sRANKL and FGF-23 in the HCHF animals. Only 100 mg/kg annatto and palm tocotrienol lowered SOST and DKK-1 levels in the HCHF animals. In conclusion, tocotrienol exerts potential skeletal-promoting benefit by modulating the levels of osteocytes-derived bone-related peptides.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism
Fulltext Inflammasomes and Pyroptosis as Therapeutic Targets for COVID-19

Yap JKY, Moriyama M, Iwasaki A

J Immunol, 2020 Jul 15;205(2):307-312.
PMID: 32493814 DOI: 10.4049/jimmunol.2000513

The inflammatory response to severe acute respiratory syndrome-related coronavirus 2 infection has a direct impact on the clinical outcomes of coronavirus disease 2019 patients. Of the many innate immune pathways that are engaged by severe acute respiratory syndrome-related coronavirus 2, we highlight the importance of the inflammasome pathway. We discuss available pharmaceutical agents that target a critical component of inflammasome activation, signaling leading to cellular pyroptosis, and the downstream cytokines as a promising target for the treatment of severe coronavirus disease 2019-associated diseases.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism
Fulltext Significant Decreased Expressions of CaN, VEGF, SLC39A6 and SFRP1 in MDA-MB-231 Xenograft Breast Tumor Mice Treated with Moringa oleifera Leaves and Seed Residue (MOLSr) Extracts

Lim WF, Mohamad Yusof MI, Teh LK, Salleh MZ

Nutrients, 2020 Sep 30;12(10).
PMID: 33007803 DOI: 10.3390/nu12102993

Moringa oleifera is a miracle plant with many nutritional and medicinal properties. Chemopreventive values of the combined mixture of moringa leaves and seed residue (MOLSr) at different ratios (M1S9, M1S1 and M9S1) were investigated. MOLSr extracts were subjected to phytochemical screening, antioxidant assays, metabolite profiling and cytotoxic activity on the primary mammary epithelial cells (PMECs), non-malignant Chang's liver cells and various human cancer cell lines (including breast, cervical, colon and liver cancer cell lines). The MOLSr ratio with the most potent cytotoxic activity was used in xenograft mice injected with MDA-MB-231 cells for in vivo tumorigenicity study as well as further protein and gene expression studies. M1S9, specifically composed of saponin and amino acid, retained the lowest antioxidant activity but the highest glucosinolate content as compared to other ratios. Cell viability decreased significantly in MCF-7 breast cancer cells and PMECs after treatment with M1S9. Solid tumor from MDA-MB-231 xenograft mice was inhibited by up to 64.5% at third week after treatment with high-dose M1S9. High-dose M1S9 significantly decreased the expression of calcineurin (CaN) and vascular endothelial cell growth factor (VEGF) proteins as well as the secreted frizzled-related protein 1 (SFRP1) and solute carrier family 39 member 6 (SLC39A6) genes. This study provides new scientific evidence for the chemoprevention potential of MOLSr extracts in a breast cancer model; however, the precise mechanism warrants further investigation.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins
Fulltext Salivary bacterial shifts in oral leukoplakia resemble the dysbiotic oral cancer bacteriome

Gopinath D, Kunnath Menon R, Chun Wie C, Banerjee M, Panda S, Mandal D, et al.

J Oral Microbiol, 2020 Dec 09;13(1):1857998.
PMID: 33391629 DOI: 10.1080/20002297.2020.1857998

Objective: While some oral carcinomas appear to arise de novo, others develop within long-standing conditions of the oral cavity that have malignant potential, now known as oral potentially malignant disorders (OPMDs). The oral bacteriome associated with OPMD has been studied to a lesser extent than that associated with oral cancer. To characterize the association in detail we compared the bacteriome in whole mouth fluid (WMF) in patients with oral leukoplakia, oral cancer and healthy controls. Methods: WMF bacteriome from 20 leukoplakia patients, 31 patients with oral cancer and 23 healthy controls were profiled using the Illumina MiSeq platform. Sequencing reads were processed using DADA2, and taxonomical classification was performed using the phylogenetic placement method. Sparse Partial Least Squares Regression Discriminant Analysis model was used to identify bacterial taxa that best discriminate the studied groups. Results: We found considerable overlap between the WMF bacteriome of leukoplakia and oral cancer while a clearer separation between healthy controls and the former two disorders was observed. Specifically, the separation was attributed to 14 taxa belonging to the genera Megaspheara, unclassified enterobacteria, Prevotella, Porphyromonas, Rothia and Salmonella, Streptococcus, and Fusobacterium. The most discriminative bacterial genera between leukoplakia and oral cancer were Megasphaera, unclassified Enterobacteriae, Salmonella and Prevotella.Conclusion: Oral bacteria may play a role in the early stages of oral carcinogenesis as a dysbiotic bacteriome is associated with oral leukoplakia and this resembles that of oral cancer more than healthy controls. Our findings may have implications for developing oral cancer prevention strategies targeting early microbial drivers of oral carcinogenesis.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins
Systemic fusarium infection in cancer patients : a report of two cases

Mohamed, M., Ariffin, H., Arasu, A., Tuck Soon, S.H., Abdullah, W.A., Lin, H.P.

Malaysian Journal of Paediatrics and Child Health, 1998;10(2):55-58.
MyJurnal

Fusarium species is an emerging genus of fungal pathogens which until recently were rare causes of human disease apart from localized infection of the skin and nails. Two cases of fungaemia due to Fusarium sp. in children are described. The first child, an 8-year old girl with acute myeloid leukaemia developed character-sitic pyoderma gangrenosum-like skin lesions before succumbing to disseminated Fusarium infection and acute respiratory distress syndrome. The second child, a 5-month old boy, developed pneumonia associated with a transient erythematous skin rash while on chemother-apy for congenital leukaemia. Both patients had Fusarium isolated from blood. The second child improved after six weeks of treatment with ampho-tericin B and granulocyte-macrophage colony stimulat-ing factor but ultimately she died of the disease follow-ing discharge. Fusarium spp should be recognised as an opportunistic pathogen in immunocompromised patients. Current literature suggests that liposomal amphotericin B in conjunction with leukocyte growth factors are the treatment of choice in this potentially fatal infection.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins
Differential expression of Notch receptors and their ligands in desmoplastic ameloblastoma

Siar CH, Nakano K, Han PP, Nagatsuka H, Ng KH, Kawakami T

J Oral Pathol Med, 2010 Aug 1;39(7):552-8.
PMID: 20337864 DOI: 10.1111/j.1600-0714.2009.00871.x

In mammals, the Notch gene family encodes four receptors (Notch1-4), and all of them are important for cell fate decisions. Notch signaling pathway plays an essential role in tooth development. The ameloblastoma, a benign odontogenic epithelial neoplasm, histologically recapitulates the enamel organ at bell stage. Notch has been detected in the plexiform and follicular ameloblastoma. Its activity in the desmoplastic ameloblastoma is unknown.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/analysis
Squamous odontogenic tumor of the mandible: a case report demonstrating immunoexpression of Notch1, 3, 4, Jagged1 and Delta1

Siar CH, Nakano K, Ng KH, Tomida M, Nagatsuka H, Kawakami T

Eur J Med Res, 2010 Apr 08;15(4):180-4.
PMID: 20554499

BACKGROUND: Squamous odontogenic tumor (SOT) is a rare benign odontogenic epithelial neoplasm. A slow-growing painless expansive swelling is the common presenting symptom. Histopathologically, SOT can be easily misdiagnosed as an acanthomatous ameloblastoma. Although Notch receptors and ligands have been shown to play a role in cell fate decisions in ameloblastomas, the role of these cell signaling molecules in SOT is unknown.
CASE REPORT: This paper describes a case of SOT affecting the anterior mandible of a 10-year-old Indian female. The patient was treated by local surgical excision and there has been no follow-up clinical record of recurrence 5 years after primary treatment. Histo?pathological examination revealed a solid, locally-infiltrative neoplasm composed of bland-looking squamatoid islands scattered in a mature fibrous connective tissue stroma and the diagnosis was SOT. Immunohistochemical evaluation showed positive reactivity of varying intensity in the neoplastic epithelial cells for Notch1, Notch3, Notch4, and their ligands Jagged1 and Delta1. Expression patterns showed considerable overlap. No immunoreactivity was detected for Notch2 and Jagged2.
CONCLUSIONS: Present findings suggest that Notch receptors and their ligands play differential roles in the cytodifferentiation of SOT.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism*
A targeted approach to genome-wide studies reveals new genetic associations with central corneal thickness

Benson MD, Khor CC, Gage PJ, Lehmann OJ

Mol Vis, 2017;23:952-962.
PMID: 29296075

Purpose: To evaluate the ability of a targeted genome-wide association study (GWAS) to identify genes associated with central corneal thickness (CCT).
Methods: A targeted GWAS was used to investigate whether ten candidate genes with known roles in corneal development were associated with CCT in two Singaporean populations. The single nucleotide polymorphisms (SNPs) within a 500 kb interval encompassing each candidate were analyzed, and in light of the resulting data, members of the Wnt pathway were subsequently screened using similar methodology.
Results: Variants within the 500 kb interval encompassing three candidate genes, DKK1 (rs1896368, p=1.32×10-3), DKK2 (rs17510449, p=7.34×10-4), and FOXO1 (rs7326616, p=1.56×10-4 and rs4943785, p=1.19×10-3), were statistically significantly associated with CCT in the Singapore Indian population. DKK2 was statistically significantly associated with CCT in a separate Singapore Malaysian population (rs10015200, p=2.26×10-3). Analysis of Wnt signaling pathway genes in each population demonstrated that TCF7L2 (rs3814573, p=1.18×10-3), RYK (rs6763231, p=1.12×10-3 and rs4854785, p=1.11×10-3), and FZD8 (rs640827, p=5.17×10-4) were statistically significantly associated with CCT.
Conclusions: The targeted GWAS identified four genes (DKK1, DKK2, RYK, and FZD8) with novel associations with CCT and confirmed known associations with two genes, FOXO1 and TCF7L2. All six participate in the Wnt pathway, supporting a broader role for Wnt signaling in regulating the thickness of the cornea. In parallel, this study demonstrated that a hypothesis-driven candidate gene approach can identify associations in existing GWAS data sets.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/genetics
Fulltext Genome-wide meta-analysis identifies five new susceptibility loci for pancreatic cancer

Klein AP, Wolpin BM, Risch HA, Stolzenberg-Solomon RZ, Mocci E, Zhang M, et al.

Nat Commun, 2018 02 08;9(1):556.
PMID: 29422604 DOI: 10.1038/s41467-018-02942-5

In 2020, 146,063 deaths due to pancreatic cancer are estimated to occur in Europe and the United States combined. To identify common susceptibility alleles, we performed the largest pancreatic cancer GWAS to date, including 9040 patients and 12,496 controls of European ancestry from the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4). Here, we find significant evidence of a novel association at rs78417682 (7p12/TNS3, P = 4.35 × 10-8). Replication of 10 promising signals in up to 2737 patients and 4752 controls from the PANcreatic Disease ReseArch (PANDoRA) consortium yields new genome-wide significant loci: rs13303010 at 1p36.33 (NOC2L, P = 8.36 × 10-14), rs2941471 at 8q21.11 (HNF4G, P = 6.60 × 10-10), rs4795218 at 17q12 (HNF1B, P = 1.32 × 10-8), and rs1517037 at 18q21.32 (GRP, P = 3.28 × 10-8). rs78417682 is not statistically significantly associated with pancreatic cancer in PANDoRA. Expression quantitative trait locus analysis in three independent pancreatic data sets provides molecular support of NOC2L as a pancreatic cancer susceptibility gene.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins
Insulin-transferrin-selenium prevent human chondrocyte dedifferentiation and promote the formation of high quality tissue engineered human hyaline cartilage

Chua KH, Aminuddin BS, Fuzina NH, Ruszymah BH

Eur Cell Mater, 2005 Jun 17;9:58-67; discussion 67.
PMID: 15962238

This study was to investigate the effects of insulin-transferrin-selenium (ITS) on the proliferation and quantitative gene expression of adult human nasal septum chondrocytes in monolayer culture expansion and the formation of tissue engineered hyaline cartilage. Effects of ITS on human nasal septum chondrocytes monolayer culture expansion and gene expression were evaluated in various culture media either added with 2% fetal bovine serum (FBS) or 1 ng/mL basic fibroblast growth factor plus 1 ng/mL transforming growth factor or both serum and growth factors supplementation in comparison with medium added with 10%FBS. Chondrocytes cultured in medium added with 2% fetal bovine serum and growth factors either supplemented with or without ITS were then mixed with pluronic F-127 hydrogel for in vivo tissue engineered cartilage formation in nude mice model. Engineered tissues were removed after 8 weeks of implantation and evaluated with histological staining, immunohistochemistry, transmission electron microscopy and quantitative gene expression analysis. ITS promoted human chondrocytes proliferation and reduced chondrocytes dedifferentiation in media supplemented with serum and growth factors. ITS with 2% FBS and growth factors provided 15-fold increased in chondrocytes number by the end of the culture period compared to the standard culture medium used in chondrocytes culture (medium added with 10% FBS). Engineered tissue resulted from ITS supplementation demonstrated higher quality of cartilage formation. In conclusion, our study has demonstrated the benefits of ITS supplementation in human chondrocytes monolayer culture and tissue engineering cartilage formation.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins

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