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The International Journal of... 2006The cellular and developmental analysis of evolutionary-conserved genes directing bilaterian mesodermal and myogenic cell fate previously identified the hydromedusan... (Comparative Study)
Comparative Study Review
The cellular and developmental analysis of evolutionary-conserved genes directing bilaterian mesodermal and myogenic cell fate previously identified the hydromedusan entocodon and its differentiation product, the striated muscle, as mesodermal derivatives. In view of these findings we presented a hypothesis disputing the diploblast classification of cnidarians without providing further explanations for the apparent diploblasty of the polyp stage and the formation of the subepidermal striated muscle in those Medusozoa lacking the entocodon nodule (Seipel and Schmid, 2005). Hence we carried out a systematic review of the histological and experimental evidence for mesodermal differentiations in cnidarians. In anthozoan and scyphozoan but not in hydrozoan polyps the presumptive mesodermal elements include amoeboid cells, the mesentery retractor muscles and scleroblasts, all of which are embedded or deeply rooted in the extracellular matrix (mesoglea) and derive from the ectoblastemal cells invading the extracellular matrix from the gastrulation site during or shortly after endoderm formation. These data lend further support to the cnidarian mesodermate hypothesis, whereby cnidarians and bilaterians share a common triploblast ancestor, the Urtriploblast, a small, motile, possibly medusa-like organism that did not feature a sessile polyp stage in its life cycle. As a consequence the diploblasty of the hydrozoan polyps may represent a derived morphology resulting from heterochronic modulations of the gastrulation process after endoderm formation.
Topics: Animals; Cell Differentiation; Cnidaria; Germ Layers; Life Cycle Stages; Mesoderm; Models, Biological; Muscle, Skeletal
PubMed: 16892172
DOI: 10.1387/ijdb.062150ks -
Iranian Journal of Medical Sciences Feb 2024Some studies have evaluated the manipulation of the sonic hedgehog (Shh) signaling pathway to generate more efficient insulin-producing cells (IPCs). In a systematic... (Review)
Review
BACKGROUND
Some studies have evaluated the manipulation of the sonic hedgehog (Shh) signaling pathway to generate more efficient insulin-producing cells (IPCs). In a systematic review, we evaluated and studies on the effect of inhibition or activation of the Shh pathway on the production, differentiation, maintenance, and endocrine activity of IPCs.
METHODS
A systematic review was conducted using all available experimental studies published between January 2000 and November 2022. The review aimed at determining the effect of Shh manipulation on the differentiation of stem cells (SCs) into IPCs. Keywords and phrases using medical subject headings were extracted, and a complete search was performed in Web of Science, Embase, ProQuest, PubMed, Scopus, and Cochrane Library databases. The inclusion criteria were manipulation of Shh in SCs, SCs differentiation into IPCs, and endocrine activity of mature IPCs. Articles with incomplete data and duplications were excluded.
RESULTS
A total of 208 articles were initially identified, out of which 11 articles were included in the study. The effect of Shh inhibition in the definitive endoderm stage to produce functional IPCs were confirmed. Some studies showed the importance of Shh re-activation at late-stage differentiation for the generation of efficient IPCs. It is proposed that baseline concentrations of Shh in mature pancreatic β-cells affect insulin secretion and endocrine activities of the cells. However, Shh overexpression in pancreatic β-cells ultimately leads to improper endocrine function and inadequate glucose-sensing insulin secretion.
CONCLUSION
Accurate manipulation of the Shh signaling pathway can be an effective approach in the production and maintenance of functional IPCs.
Topics: Hedgehog Proteins; Insulin; Cell Differentiation; Signal Transduction; Insulin-Secreting Cells
PubMed: 38356490
DOI: 10.30476/ijms.2023.95425.2678 -
Frontiers in Oncology 2023The canonical Wnt inhibitor Dickkopf-1 (Dkk-1) has the capacity to modulate homeostasis between canonical and non-canonical Wnt pathways and also signal independently of...
BACKGROUND
The canonical Wnt inhibitor Dickkopf-1 (Dkk-1) has the capacity to modulate homeostasis between canonical and non-canonical Wnt pathways and also signal independently of Wnt. The specific effects of Dkk-1 activity on tumor physiology are therefore unpredictable with examples of Dkk-1 serving as either a driver or suppressor of malignancy. Given that Dkk-1 blockade may serve as a potential treatment for some types of cancer, we questioned whether it is possible to predict the role of Dkk-1 on tumor progression based on the tissue origin of the tumor.
METHODS
Original research articles that described Dkk-1 in terms a tumor suppressor or driver of cancer growth were identified. To determine the association between tumor developmental origin and the role of Dkk-1, a logistic regression was performed. The Cancer Genome Atlas database was interrogated for survival statistics based on tumor Dkk-1 expression.
RESULTS
We report that Dkk-1 is statistically more likely to serve as a suppressor in tumors arising from the ectoderm ( = 0.0198) or endoderm ( = 0.0334) but more likely to serve as a disease driver in tumors of mesodermal origin ( = 0.0155). Survival analyses indicated that in cases where Dkk-1 expression could be stratified, high Dkk-1 expression is usually associated with poor prognosis. This in part may be due to pro-tumorigenic role Dkk-1 plays on tumor cells but also through its influence on immunomodulatory and angiogenic processes in the tumor stroma.
CONCLUSION
Dkk-1 has a context-specific dual role as a tumor suppressor or driver. Dkk-1 is significantly more likely to serve as a tumor suppressor in tumors arising from ectoderm and endoderm while the converse is true for mesodermal tumors. Patient survival data indicated high Dkk-1 expression is generally a poor prognostic indicator. These findings provide further support for the importance of Dkk-1 as a therapeutic cancer target in some cases.
PubMed: 37007131
DOI: 10.3389/fonc.2023.1114822 -
World Journal of Stem Cells Nov 2019Mesenchymal stem cells are pluripotent cells that have the ability to generate cells from a cell line or in other cell types from different tissues but from the same...
BACKGROUND
Mesenchymal stem cells are pluripotent cells that have the ability to generate cells from a cell line or in other cell types from different tissues but from the same origin. Although those cells have more limited differentiation capacity than embryonic stem cells, they are easily obtained from somatic tissue and can be grown in large quantities. This characteristic of undifferentiated stem cells differentiating into different cell lines arouses strategies in regenerative medicine for the treatment of different diseases such as neurodegenerative diseases.
AIM
To evaluate the cell differentiation capacity of human breastmilk stem cells for the three germ layers by a systematic review.
METHODS
The searched databases were PubMed, EMBASE, OVID, and COCHRANE LIBRARY, published between 2007 and 2018 in the English language. All were studies for analysis of the "cell differentiation potential" in the literature using the keywords "human breastmilk," "stem cells," and keywords combined with the Boolean operator "NOT" were used to exclude those articles that had the word "CANCER" and their respective synonyms, which were previously consulted according to medical subject heading terms. PRISMA 2009 guidelines were followed in this study.
RESULTS
A total of 315 titles and abstracts of articles were examined. From these, 21 were in common with more than one database, leaving 294 articles for analysis. Of that total, five publications met the inclusion criteria. When analyzing the publications, it was demonstrated that human breastmilk stem cells have a high cellular plasticity, exhibiting the ability to generate cells of all three germ layers, endoderm, mesoderm, and ectoderm, demonstrating their stemness. Those cells expressed the genes, TRA-1-60/81, octamer-binding transcription factor 4, and NANOG, of which NANOG, a critical regulator for self-renewal and maintenance, was the most highly expressed. Those cells have the ability to differentiate into adipocytes, chondrocytes, osteocytes, oligodendrocytes, astrocytes, and neurons as well hepatocytes, β-pancreatic cells, and cardiomyocytes.
CONCLUSION
Although the literature has been scarce, the pluripotentiality of these cells represents great potential for tissue engineering and cellular therapy. Further studies for safe clinical translation are needed.
PubMed: 31768226
DOI: 10.4252/wjsc.v11.i11.1005