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Cell Death & Disease Sep 2023Krüppel-like factor 4 (KLF4) is an evolutionarily conserved zinc finger-containing transcription factor that regulates diverse cellular processes such as cell...
Krüppel-like factor 4 (KLF4) is an evolutionarily conserved zinc finger-containing transcription factor that regulates diverse cellular processes such as cell proliferation, apoptosis, and differentiation. Our previous study showed that KLF4 expression is upregulated in skeletal muscle ontogeny during embryonic development in pigs, suggesting its importance for skeletal muscle development and muscle function. We revealed here that KLF4 plays a critical role in skeletal muscle development and regeneration. Specific knockout of KLF4 in skeletal muscle impaired muscle formation further affecting physical activity and also defected skeletal muscle regeneration. In vitro, KLF4 was highly expressed in proliferating myoblasts and early differentiated cells. KLF4 knockdown promoted myoblast proliferation and inhibited myoblast fusion, while its overexpression showed opposite results. Mechanically, in proliferating myoblasts, KLF4 inhibits myoblast proliferation through regulating cell cycle arrest protein P57 by directly targeting its promoter; while in differentiated myoblasts, KLF4 promotes myoblast fusion by transcriptionally activating Myomixer. Our study provides mechanistic information for skeletal muscle development, reduced muscle strength and impaired regeneration after injury and unveiling the mechanism of KLF4 in myogenic regulation.
Topics: Female; Pregnancy; Animals; Swine; Kruppel-Like Factor 4; Muscle Development; Cell Differentiation; Apoptosis; Cell Cycle Proteins; Muscle, Skeletal
PubMed: 37723138
DOI: 10.1038/s41419-023-06136-w -
Cell Reports Jan 2024Blood flow is known to regulate cerebrovascular development through acting on vascular endothelial cells (ECs). As an indispensable component of the neurovascular unit,...
Blood flow is known to regulate cerebrovascular development through acting on vascular endothelial cells (ECs). As an indispensable component of the neurovascular unit, brain pericytes physically couple with ECs and play vital roles in blood-brain barrier integrity maintenance and neurovascular coupling. However, it remains unclear whether blood flow affects brain pericyte development. Using in vivo time-lapse imaging of larval zebrafish, we monitored the developmental dynamics of brain pericytes and found that they proliferate to expand their population and increase their coverage to brain vessels. In combination with pharmacological and genetic approaches, we demonstrated that blood flow enhances brain pericyte proliferation through Piezo1 expressed in ECs. Moreover, we identified that EC-intrinsic Notch signaling is downstream of Piezo1 to promote the activation of Notch signaling in pericytes. Thus, our findings reveal a role of blood flow in pericyte proliferation, extending the functional spectrum of hemodynamics on cerebrovascular development.
Topics: Animals; Pericytes; Zebrafish; Endothelial Cells; Brain; Blood-Brain Barrier; Hemodynamics; Cell Proliferation; Ion Channels; Zebrafish Proteins
PubMed: 38175750
DOI: 10.1016/j.celrep.2023.113652 -
Global Medical Genetics Dec 2023This review article discusses the epigenetic regulation of quiescent stem cells. Quiescent stem cells are a rare population of stem cells that remain in a state of cell... (Review)
Review
This review article discusses the epigenetic regulation of quiescent stem cells. Quiescent stem cells are a rare population of stem cells that remain in a state of cell cycle arrest until activated to proliferate and differentiate. The molecular signature of quiescent stem cells is characterized by unique epigenetic modifications, including histone modifications and deoxyribonucleic acid (DNA) methylation. These modifications play critical roles in regulating stem cell behavior, including maintenance of quiescence, proliferation, and differentiation. The article specifically focuses on the role of histone modifications and DNA methylation in quiescent stem cells, and how these modifications can be dynamically regulated by environmental cues. The future perspectives of quiescent stem cell research are also discussed, including their potential for tissue repair and regeneration, their role in aging and age-related diseases, and their implications for cancer research. Overall, this review provides a comprehensive overview of the epigenetic regulation of quiescent stem cells and highlights the potential of this research for the development of new therapies in regenerative medicine, aging research, and cancer biology.
PubMed: 38025190
DOI: 10.1055/s-0043-1777072 -
Cancer Medicine Aug 2023Gastric cancer is a highly heterogeneous disease, which makes it challenging to develop effective targeted therapies. Although the potassium voltage-gated channel...
BACKGROUND
Gastric cancer is a highly heterogeneous disease, which makes it challenging to develop effective targeted therapies. Although the potassium voltage-gated channel subfamily D (KCND) channels, particularly KCND2 (also known as Kv4.2), have found evidence of involvement in the occurrence and development of various cancers, there are still some limitations in our understanding of KCND2's roles in gastric cancer.
METHODS
We analyzed the correlation between KCND2 expression and clinical features as well as immune infiltration using the Cancer Genome Atlas (TCGA) database. Functional assays of KCND2 were conducted using Cell counting Kit-8 (CCK8), clone formation assay and cell cycle analysis. Additionally, immunofluorescence, flow cytometry and quantitative real-time polymerase chain reaction (qRT-PCR) techniques were used to investigate tumor proliferation and immune cell infiltration at different levels of KCND2 expression in vivo.
RESULTS
KCND2 was markedly elevated in gastric cancer and its expression appeared to link to different grades, T stages, and N stages. In addition, KCND2 was an independent predictor of prognosis, and its elevated levels in TCGA database revealed a more unfavorable prognosis for patients with gastric cancer. KCND2 strengthened the viability at the cellular level by boosting the proliferation of gastric cancer cells and reducing their death rate. Additionally, it also highlights that KCND2 the abilities of proliferating of gastric cancer cells by stimulating NF-κB both in cell and animal levels. In addition, the findings provided proof that in animal levels, KCND2 might regulate the immune system by associating with promoting M2 macrophages, which are known to play critical roles in cancer progression. Mechanistically, KCND2 was found to lead to the infiltration of M2 macrophages through activation of NF-κB, ultimately promoting the advancement of gastric cancer.
CONCLUSION
Overall, these findings suggest that KCND2 is likely to be available as an underlying therapeutic target for gastric cancer.
Topics: Animals; Stomach Neoplasms; Prognosis; NF-kappa B; Immunity; Biomarkers
PubMed: 37347147
DOI: 10.1002/cam4.6236 -
Epigenetics Dec 2023Prostate cancer is the most prevalent type of cancer among men worldwide. The importance of circular RNA (circRNA) in prostate cancer and its connection to malignancy...
Prostate cancer is the most prevalent type of cancer among men worldwide. The importance of circular RNA (circRNA) in prostate cancer and its connection to malignancy has been steadily recognized. circRNA expression was obtained by circRNA sequencing of prostate cancer. circRNA and its function were further analysed. The results were verified by qRT-PCR, RIP assay, FISH, RNA pulldown, WB, CCK-8, colony formation assay and wound-healing assay. BALB/c Nude mice were used for xenograft hosts. Low expression of circDHRS3 was assessed in prostate cancer. Overexpression of circDHRS3 inhibited prostate cancer growth and migration . Additionally, miR-421 was shown to be the downstream target of circDHRS3, as shown by fluorescence hybridization and dual-luciferase experiments. The rescue assay results for the PC3 and Du145 cell lines demonstrated that circDHRS3 inhibits prostate cancer cell lines' ability to proliferate and metastasize by modulating MEIS2 expression through the circDHRS3/miR-421/MEIS2 axis. investigations confirmed that the overexpression of circDHRS3 could inhibit both the lung and bone metastasis of prostate cancer cells. circDHRS3 has the potential to become a biomarker and a targeted therapeutic site for prostate cancer, particularly in the malignant stage. Our study indicates that circDHRS3 inhibits prostate cancer cell proliferation and metastasis through the circDHRS3/miR-421/MEIS2 axis.
Topics: Animals; Humans; Male; Mice; Cell Line, Tumor; Cell Movement; Cell Proliferation; DNA Methylation; Gene Expression Regulation, Neoplastic; Homeodomain Proteins; In Situ Hybridization, Fluorescence; Mice, Nude; MicroRNAs; Prostatic Neoplasms; RNA, Circular; Transcription Factors; Alcohol Oxidoreductases
PubMed: 36840946
DOI: 10.1080/15592294.2023.2178802 -
Molecular Oncology Oct 2023Changes in FOXA1 (forkhead box protein A1) protein levels are well associated with prostate cancer (PCa) progression. Unfortunately, direct targeting of FOXA1 in...
Changes in FOXA1 (forkhead box protein A1) protein levels are well associated with prostate cancer (PCa) progression. Unfortunately, direct targeting of FOXA1 in progressive PCa remains challenging due to variations in FOXA1 protein levels, increased FOXA1 mutations at different stages of PCa, and elusive post-translational FOXA1 regulating mechanisms. Here, we show that SKP2 (S-phase kinase-associated protein 2) catalyzes K6- and K29-linked polyubiquitination of FOXA1 for lysosomal-dependent degradation. Our data indicate increased SKP2:FOXA1 protein ratios in stage IV human PCa compared to stages I-III, together with a strong inverse correlation (r = -0.9659) between SKP2 and FOXA1 levels, suggesting that SKP2-FOXA1 protein interactions play a significant role in PCa progression. Prostate tumors of Pten/Trp53 mice displayed increased Skp2-Foxa1-Pcna signaling and colocalization, whereas disruption of the Skp2-Foxa1 interplay in Pten/Trp53/Skp2 triple-null mice demonstrated decreased Pcna levels and increased expression of Foxa1 and luminal positive cells. Treatment of xenograft mice with the SKP2 inhibitor SZL P1-41 decreased tumor proliferation, SKP2:FOXA1 ratios, and colocalization. Thus, our results highlight the significance of the SKP2-FOXA1 interplay on the luminal lineage in PCa and the potential of therapeutically targeting FOXA1 through SKP2 to improve PCa control.
Topics: Animals; Humans; Male; Mice; Hepatocyte Nuclear Factor 3-alpha; Lysosomes; Mice, Knockout; Proliferating Cell Nuclear Antigen; Prostatic Neoplasms; Ubiquitination
PubMed: 37491794
DOI: 10.1002/1878-0261.13497 -
Arteriosclerosis, Thrombosis, and... Aug 2023Collateral arteries act as natural bypasses which reroute blood flow to ischemic regions and facilitate tissue regeneration. In an injured heart, neonatal artery...
BACKGROUND
Collateral arteries act as natural bypasses which reroute blood flow to ischemic regions and facilitate tissue regeneration. In an injured heart, neonatal artery endothelial cells orchestrate a systematic series of cellular events, which includes their outward migration, proliferation, and coalescence into fully functional collateral arteries. This process, called artery reassembly, aids complete cardiac regeneration in neonatal hearts but is absent in adults. The reason for this age-dependent disparity in artery cell response is completely unknown. In this study, we investigated if regenerative potential of coronary arteries is dictated by their ability to dedifferentiate.
METHODS
Single-cell RNA sequencing of coronary endothelial cells was performed to identify differences in molecular profiles of neonatal and adult endothelial cells in mice. Findings from this in silico analyses were confirmed with in vivo experiments using genetic lineage tracing, whole organ immunostaining, confocal imaging, and cardiac functional assays in mice.
RESULTS
Upon coronary occlusion, neonates showed a significant increase in actively cycling artery cells and expressed prominent dedifferentiation markers. Data from in silico pathway analyses and in vivo experiments suggested that upon myocardial infarction, cell cycle reentry of preexisting neonatal artery cells, the subsequent collateral artery formation, and recovery of cardiac function are dependent on arterial VegfR2 (vascular endothelial growth factor receptor-2). This subpopulation of dedifferentiated and proliferating artery cells was absent in nonregenerative postnatal day 7 or adult hearts.
CONCLUSIONS
These data indicate that adult artery endothelial cells fail to drive collateral artery development due to their limited ability to dedifferentiate and proliferate.
Topics: Animals; Mice; Endothelial Cells; Vascular Endothelial Growth Factor A; Collateral Circulation; Coronary Vessels; Cell Proliferation
PubMed: 37345524
DOI: 10.1161/ATVBAHA.123.319319 -
Frontiers in Bioengineering and... 2023Ammonia (Amm), and its aqueous solved state, ammonium, which is produced from glutamine (Gln) metabolism, is a known inhibitor of stem cell proliferation . In the...
Ammonia (Amm), and its aqueous solved state, ammonium, which is produced from glutamine (Gln) metabolism, is a known inhibitor of stem cell proliferation . In the context of cultivated beef, primary bovine fibro-adipogenic progenitor cells (FAPs) need to be grown and differentiated for several weeks for the production of cultivated fat. In this study, the ammonium sensitivity of these cells was investigated by introducing ammonium chloride, which was found to inhibit their proliferation when above 5 mM and their adipogenic differentiation when above 2 mM. Novel serum-free proliferation and differentiation media were hence developed with the aim to suppress Amm production during expansion and adipogenesis. Glutamine substitutes, such as a-ketoglutarate (aKG), glutamate (Glt) and pyruvate (Pyr) were investigated. It was found that aKG based proliferation medium (PM) was the most effective in promoting and maintaining FAPs growth over several passages while the specific Amm production rate was reduced more than 5-fold. In terms of differentiation capacity, the substitution of glucose (Gluc) and Gln with galactose (Gal) and Pyr was shown to be the most effective in promoting FAPs differentiation into mature adipocytes, resulting in over 2-fold increase of fat volume per cell, while suppressing Amm production. Our findings suggest that FAPs do not require Gln as an essential nutrient but, on the contrary, possess all the necessary metabolic pathways to proliferate and subsequently differentiate in a Gln-free medium, resulting in decreased Amm production rates and seemingly synthesising glutamine . These findings are important for prolonging the lifespan of culture medium, allowing for reduced costs and process interventions.
PubMed: 37555077
DOI: 10.3389/fbioe.2023.1202165 -
BMC Genomics Jul 2023Skeletal muscle is the largest tissue in the body, and it affects motion, metabolism and homeostasis. Skeletal muscle development comprises myoblast proliferation,...
BACKGROUND
Skeletal muscle is the largest tissue in the body, and it affects motion, metabolism and homeostasis. Skeletal muscle development comprises myoblast proliferation, fusion and differentiation to form myotubes, which subsequently form mature muscle fibres. This process is strictly regulated by a series of molecular networks. Increasing evidence has shown that noncoding RNAs, especially microRNAs (miRNAs), play vital roles in regulating skeletal muscle growth. Here, we showed that miR-668-3p is highly expressed in skeletal muscle.
METHODS
Proliferating and differentiated C2C12 cells were transfected with miR-668-3p mimics and/or inhibitor, and the mRNA and protein levels of its target gene were evaluated by RT‒qPCR and Western blotting analysis. The targeting of Appl1 by miR-668-3p was confirmed by dual luciferase assay. The interdependence of miR-668-3p and Appl1 was verified by cotransfection of C2C12 cells.
RESULTS
Our data reveal that miR-668-3p can inhibit myoblast proliferation and myogenic differentiation. Phosphotyrosine interacting with PH domain and leucine zipper 1 (Appl1) is a target gene of miR-668-3p, and it can promote myoblast proliferation and differentiation by activating the p38 MAPK pathway. Furthermore, the inhibitory effect of miR-668-3p on myoblast cell proliferation and myogenic differentiation could be rescued by Appl1.
CONCLUSION
Our results indicate a new mechanism by which the miR-668-3p/Appl1/p38 MAPK pathway regulates skeletal muscle development.
Topics: Cell Line; Cell Differentiation; MicroRNAs; Myoblasts; Cell Proliferation; Muscle Development
PubMed: 37488537
DOI: 10.1186/s12864-023-09431-0 -
Science Advances Nov 2023Despite their importance in tissue maintenance and repair, fibroblast diversity and plasticity remain poorly understood. Using single-cell RNA sequencing, we uncover...
Despite their importance in tissue maintenance and repair, fibroblast diversity and plasticity remain poorly understood. Using single-cell RNA sequencing, we uncover distinct sclerotome-derived fibroblast populations in zebrafish, including progenitor-like perivascular/interstitial fibroblasts, and specialized fibroblasts such as tenocytes. To determine fibroblast plasticity in vivo, we develop a laser-induced tendon ablation and regeneration model. Lineage tracing reveals that laser-ablated tenocytes are quickly regenerated by preexisting fibroblasts. By combining single-cell clonal analysis and live imaging, we demonstrate that perivascular/interstitial fibroblasts actively migrate to the injury site, where they proliferate and give rise to new tenocytes. By contrast, perivascular fibroblast-derived pericytes or specialized fibroblasts, including tenocytes, exhibit no regenerative plasticity. Active Hedgehog (Hh) signaling is required for the proliferation of activated fibroblasts to ensure efficient tenocyte regeneration. Together, our work highlights the functional diversity of fibroblasts and establishes perivascular/interstitial fibroblasts as tenocyte progenitors that promote tendon regeneration in a Hh signaling-dependent manner.
Topics: Animals; Zebrafish; Tenocytes; Hedgehog Proteins; Regeneration; Fibroblasts; Single-Cell Analysis
PubMed: 37967180
DOI: 10.1126/sciadv.adi5771