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International Journal of Molecular... Oct 2023The quality and quantity of animal meat are closely related to the development of skeletal muscle, which, in turn, is determined by myogenic cells, including myoblasts...
The quality and quantity of animal meat are closely related to the development of skeletal muscle, which, in turn, is determined by myogenic cells, including myoblasts and skeletal muscle satellite cells (SMSCs). Circular RNA, an endogenous RNA derivative formed through specific reverse splicing in mRNA precursors, has the potential to influence muscle development by binding to miRNAs or regulating gene expression involved in muscular growth at the transcriptional level. Previous high-throughput sequencing of circRNA in chicken liver tissue revealed a circular transcript, circIGF2BP3, derived from the gene encoding insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3). In this study, we confirmed the presence of the natural circular molecule of circIGF2BP3 through an RNase R enzyme tolerance assay. RT-qPCR results showed high circIGF2BP3 expression in the pectoral and thigh muscles of at embryonic ages 14 and 18, as well as at 7 weeks post-hatch. Notably, its expression increased during embryonic development, followed by a rapid decrease after birth. As well as using RT-qPCR, Edu, CCK-8, immunofluorescence, and Western blot techniques, we demonstrated that overexpressing circIGF2BP3 could promote the proliferation and differentiation of chicken primary myoblasts through upregulating genes such as proliferating cell nuclear antigen (), cyclin D1 ), cyclin E1 (), cyclin dependent kinase 2 (), myosin heavy chain (), myoblast-determining 1 (), myogenin (), and . In conclusion, circIGF2BP3 promotes the proliferation and differentiation of myoblasts in chickens. This study establishes a foundation for further investigation into the biological functions and mechanisms of circIGF2BP3 in myoblasts proliferation and differentiation.
Topics: Animals; Chickens; RNA, Circular; Cell Differentiation; MicroRNAs; Myoblasts; Cell Proliferation; RNA, Messenger; Muscle Development
PubMed: 37958531
DOI: 10.3390/ijms242115545 -
American Journal of Physiology. Cell... Sep 2023Breast cancer is the leading cause of cancer deaths for women worldwide. Endocrine therapies represent the cornerstone for hormone-dependent breast cancer treatment....
Breast cancer is the leading cause of cancer deaths for women worldwide. Endocrine therapies represent the cornerstone for hormone-dependent breast cancer treatment. However, in many cases, endocrine resistance is induced with poor prognosis for patients. In the current study, we have developed MCF-7 cell lines resistant to fulvestrant (MCF-7Fulv) and tamoxifen (MCF-7Tam) aiming at investigating mechanisms underlying resistance. Both resistant cell lines exerted lower proliferation capacity in two-dimensional (2-D) cultures but retain estrogen receptor α (ERα) expression and proliferate independent of the presence of estrogens. The established cell lines tend to be more aggressive exhibiting advanced capacity to form colonies, increased expression of epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), and heterodimerization of ERBB family receptors and activation of EGFR downstream pathways like MEK/ERK1/2 and PI3K/AKT. Tyrosine kinase inhibitors tested against resistant MCF-7Fulv and MCF-7Tam cells showed moderate efficacy to inhibit cell proliferation, except for lapatinib, which concomitantly inhibits both EGFR and HER2 receptors and strongly reduced cell proliferation. Furthermore, increased autophagy was observed in resistant MCF-7Fulv and MCF-7Tam cells as shown by the presence of autophagosomes and increased Beclin-1 levels. The increased autophagy in resistant cells is not associated with increased apoptosis, suggesting a cytoprotective role for autophagy that may favor cells' survival and aggressiveness. Thus, by exploiting those underlying mechanisms, new targets could be established to overcome endocrine resistance. The development of resistance to hormone therapy caused by both fulvestrant and tamoxifen promotes autophagy with concomitant apoptosis evasion, rendering cells capable of surviving and growing. The fact that resistance also triggers ERBB family signaling pathways, which are poorly inhibited by tyrosine kinase inhibitors might attribute to cells' aggressiveness. It is obvious that the development of endocrine therapy resistance involves a complex interplay between deregulated ERBB signaling and autophagy that may be considered in clinical practice.
Topics: Humans; Female; Breast Neoplasms; Fulvestrant; Phosphatidylinositol 3-Kinases; Cell Line, Tumor; Signal Transduction; Tamoxifen; Cell Proliferation; MCF-7 Cells; Autophagy; Drug Resistance, Neoplasm; ErbB Receptors
PubMed: 37575061
DOI: 10.1152/ajpcell.00199.2023 -
American Journal of Clinical and... 2023Increasing evidence demonstrates that long non-coding RNAs (lncRNAs) are closely related to multiple human autoimmune diseases, and their dysregulation is tightly linked...
OBJECTIVE
Increasing evidence demonstrates that long non-coding RNAs (lncRNAs) are closely related to multiple human autoimmune diseases, and their dysregulation is tightly linked to inflammation and disease progression. Nonetheless, little is known about the consequences of aberrant expression of lncRNAs during rheumatoid arthritis (RA) development. In this study, we screened for the expressions of lncRNAs in RA synovial fibroblasts (RA-SF) and investigated their functions in RA-SF proliferation and migration, and the relevant underlying mechanisms.
METHODS
The lncRNAs expression profiles were interrogated with microarrays. The expressions of key lncRNAs were confirmed in synovial fibroblasts from RA patients and MH7A cells using qRT-PCR. Proliferations and migrations of MH7A and HFL-1 cells were evaluated using CCK-8 assay and cell migration assay kits, respectively. The expression of inflammatory cytokines (IL-6, IL-1β, and TNF-α) and cell migration related proteins (MMP-1 and MMP-3) were evaluated using qRT-PCR and western blotting. Collagen type II-induced arthritis (CIA) in mice was used as an animal model of RA.
RESULTS
Nine lncRNAs were significantly altered in RA-SF, of which lncRNA-000239 showing the most significant upregulation. Overexpression of lncRNA-000239 significantly enhanced the proliferation and migration of human RS-SF cells (MH7A), while the opposite effect was observed with lncRNA-000239 silencing. Importantly, lncRNA-000239 enhanced annexin A1 expression by upregulating the expression of miR-146a. Moreover, locally enhanced expression of lncRNA-000239 promoted the onset of arthritis in CIA.
CONCLUSION
These data indicate that lncRNA-000239 upregulates annexin A1 expression via miR-146a and thus, promotes the proliferation and migration of RA-SF. This highlights a potential role of lncRNA-000239 as an inflammatory factor of RA.
PubMed: 37736077
DOI: No ID Found -
Biology Aug 2023Although microglia exist as a minor glial cell type in the normal state of the brain, they increase in number in response to various disorders and insults. However, it... (Review)
Review
Although microglia exist as a minor glial cell type in the normal state of the brain, they increase in number in response to various disorders and insults. However, it remains unclear whether microglia proliferate in the affected area, and the mechanism of the proliferation has long attracted the attention of researchers. We analyzed microglial mitosis using a facial nerve transection model in which the blood-brain barrier is left unimpaired when the nerves are axotomized. Our results showed that the levels of macrophage colony-stimulating factor (M-CSF), cFms (the receptor for M-CSF), cyclin A/D, and proliferating cell nuclear antigen (PCNA) were increased in microglia in the axotomized facial nucleus (axotFN). In vitro experiments revealed that M-CSF induced cFms, cyclin A/D, and PCNA in microglia, suggesting that microglia proliferate in response to M-CSF in vivo. In addition, M-CSF caused the activation of c-Jun N-terminal kinase (JNK) and p38, and the specific inhibitors of JNK and p38 arrested the microglial mitosis. JNK and p38 were shown to play roles in the induction of cyclins/PCNA and cFms, respectively. cFms was suggested to be induced through a signaling cascade of p38-mitogen- and stress-activated kinase-1 (MSK1)-cAMP-responsive element binding protein (CREB) and/or p38-activating transcription factor 2 (ATF2). Microglia proliferating in the axotFN are anticipated to serve as neuroprotective cells by supplying neurotrophic factors and/or scavenging excite toxins and reactive oxygen radicals.
PubMed: 37627005
DOI: 10.3390/biology12081121 -
The Journal of Clinical Investigation Nov 2023BACKGROUNDHIV-1-infected CD4+ T cells contribute to latent reservoir persistence by proliferating while avoiding immune recognition. Integration features of intact...
BACKGROUNDHIV-1-infected CD4+ T cells contribute to latent reservoir persistence by proliferating while avoiding immune recognition. Integration features of intact proviruses in elite controllers (ECs) and people on long-term therapy suggest that proviruses in specific chromosomal locations can evade immune surveillance. However, direct evidence of this mechanism is missing.METHODSIn this case report, we characterized integration sites and full genome sequences of expanded T cell clones in an EC before and after chemoradiation. We identified the cognate peptide of infected clones to investigate cell proliferation and virus production induced by T cell activation, and susceptibility to autologous CD8+ T cells.RESULTSThe proviral landscape was dominated by 2 large clones with replication-competent proviruses integrated into zinc finger (ZNF) genes (ZNF470 and ZNF721) in locations previously associated with deeper latency. A third nearly intact provirus, with a stop codon in Pol, was integrated into an intergenic site. Upon stimulation with cognate Gag peptides, infected clones proliferated extensively and produced virus, but the provirus in ZNF721 was 200-fold less inducible. While autologous CD8+ T cells decreased the proliferation of cells carrying the intergenic provirus, they had no effect on cells with the provirus in the ZNF721 gene.CONCLUSIONSWe provide direct evidence that upon activation of infected clones by cognate antigen, the lower inducibility of intact proviruses in ZNF genes can result in immune evasion and persistence.FUNDINGOffice of the NIH Director and National Institute of Dental & Craniofacial Research; NIAID, NIH; Johns Hopkins University Center for AIDS Research.
Topics: Humans; HIV-1; HIV Infections; Proviruses; CD4-Positive T-Lymphocytes; Clone Cells; Virus Latency
PubMed: 37698927
DOI: 10.1172/JCI171097 -
Haematologica Nov 2023Post-transplant lymphoproliferative disorders (PTLD) are iatrogenic immune deficiency-associated lymphoid/plasmacytic proliferations developing due to immunosuppression...
Post-transplant lymphoproliferative disorders (PTLD) are iatrogenic immune deficiency-associated lymphoid/plasmacytic proliferations developing due to immunosuppression in solid organ or hematopoietic stem cell allograft patients. PTLD are characterized by abnormal proliferation of lymphoid cells and have a heterogeneous clinical behavior. We profiled expression of >700 tumor microenvironment (TME)-related genes in 75 post-transplant aggressive B-cell lymphomas (PTABCL). Epstein-Barr virus (EBV)-positive PT-ABCL clustered together and were enriched for type I interferon pathway and antiviral-response genes. Additionally, a cytotoxicity gene signature associated with EBV-positivity and favorable overall survival (OS) (hazard ratio =0.61; P=0.019). In silico immunophenotyping revealed two subgroups with distinct immune cell compositions. The inflamed subgroup with higher proportions of immune cells had better outcome compared to noninflamed subgroup (median OS >200.0 vs. 15.2 months; P=0.006). In multivariable analysis with EBV status, International Prognostic Index, and rituximab-containing treatment, inflamed TME remained as an independent predictor for favorable outcome. We also compared TME between post-transplant and immunocompetent host diffuse large B-cell lymphomas (n=75) and discovered that the proportions of T cells were lower in PT-diffuse large B-cell lymphomas. In conclusion, we provide a comprehensive phenotypic characterization of PT-ABCL, highlighting the importance of immune cell composition of TME in determining the clinical behavior and prognosis of PT-ABCL.
Topics: Humans; Epstein-Barr Virus Infections; Herpesvirus 4, Human; Tumor Microenvironment; Rituximab; Lymphoproliferative Disorders; Lymphoma, Large B-Cell, Diffuse
PubMed: 37259566
DOI: 10.3324/haematol.2023.282831 -
Cancer Letters Jul 2024Cancer-associated fibroblasts play a crucial role within the tumor microenvironment. However, a comprehensive characterization of CAF in colorectal cancer (CRC) is still...
Cancer-associated fibroblasts play a crucial role within the tumor microenvironment. However, a comprehensive characterization of CAF in colorectal cancer (CRC) is still missing. We combined scRNA-seq and spatial proteomics to decipher fibroblast heterogeneity in healthy human colon and CRC at high resolution. Analyzing nearly 23,000 fibroblasts, we identified 11 distinct clusters and verified them by spatial proteomics. Four clusters, consisting of myofibroblastic CAF (myCAF)-like, inflammatory CAF (iCAF)-like and proliferating fibroblasts as well as a novel cluster, which we named "T cell-inhibiting CAF" (TinCAF), were primarily found in CRC. This new cluster was characterized by the expression of immune-interacting receptors and ligands, including CD40 and NECTIN2. Co-culture of CAF and T cells resulted in a reduction of the effector T cell compartment, impaired proliferation, and increased exhaustion. By blocking its receptor interaction, we demonstrated that NECTIN2 was the key driver of T cell inhibition. Analysis of clinical datasets showed that NECTIN2 expression is a poor prognostic factor in CRC and other tumors. In conclusion, we identified a new class of immuno-suppressive CAF with features rendering them a potential target for future immunotherapies.
Topics: Humans; Colorectal Neoplasms; Nectins; Cancer-Associated Fibroblasts; Signal Transduction; Tumor Microenvironment; T-Lymphocytes; Cell Proliferation; Coculture Techniques; Proteomics
PubMed: 38821255
DOI: 10.1016/j.canlet.2024.216985 -
The Journal of Poultry Science 2023A germline chimera is a useful model for developing and differentiating germ cells . Gonadal germ cells (GGCs) collected from chicken embryonic gonads may be used to...
A germline chimera is a useful model for developing and differentiating germ cells . Gonadal germ cells (GGCs) collected from chicken embryonic gonads may be used to produce germline chimeras as donor cells. However, the migratory and proliferative abilities of GGCs after transfer into recipient embryos are unclear. Here, the migratory and proliferative abilities of GGCs collected from 7-day-old White Leghorn embryos and fluorescently labeled were analyzed following transfer into the dorsal aorta of 2.5-day-old Rhode Island Red (RIR) embryos. Five days after transfer, the numbers of male and female GGCs were significantly higher in the RIR gonads than those in non-gonadal RIR organs when 50 GGCs were transferred per embryo. To analyze the temporal migration of GGCs in intermediate mesoderm, 50 GGCs were again transferred. The numbers of male and female GGCs in RIR gonads increased significantly from days 3 to 6 after transfer. To analyze GGC migration and proliferation in the gonads, a single GGC was transferred into 100 male and 100 female embryos. Five days after transfer, the frequencies of settled and proliferated GGCs were 37% (37/100) and 24% (24/100) in males, and 23% (23/100) and 8% (8/100) in females, respectively. Thus, GGCs are a heterogeneous cell population that may or may not have migratory and proliferative abilities. The heterogeneity of GGCs may be greater in females than that in males. When 50 GGCs were transplanted, almost all those present in embryos had settled and proliferated in the gonads and mesonephros. The migratory and proliferative abilities of GGCs in recipient gonads were considerably diverse in individual GGCs or between donor sexes.
PubMed: 38034482
DOI: 10.2141/jpsa.2023028 -
Frontiers in Cell and Developmental... 2023Melanoma is the deadliest form of skin cancer and develops from the melanocytes that are responsible for the pigmentation of the skin. The skin is also a highly...
Melanoma is the deadliest form of skin cancer and develops from the melanocytes that are responsible for the pigmentation of the skin. The skin is also a highly regenerative organ, harboring a pool of undifferentiated melanocyte stem cells that proliferate and differentiate into mature melanocytes during regenerative processes in the adult. Melanoma and melanocyte regeneration share remarkable cellular features, including activation of cell proliferation and migration. Yet, melanoma considerably differs from the regenerating melanocytes with respect to abnormal proliferation, invasive growth, and metastasis. Thus, it is likely that at the cellular level, melanoma resembles early stages of melanocyte regeneration with increased proliferation but separates from the later melanocyte regeneration stages due to reduced proliferation and enhanced differentiation. Here, by exploiting the zebrafish melanocytes that can efficiently regenerate and be induced to undergo malignant melanoma, we unravel the transcriptome profiles of the regenerating melanocytes during early and late regeneration and the melanocytic nevi and malignant melanoma. Our global comparison of the gene expression profiles of melanocyte regeneration and nevi/melanoma uncovers the opposite regulation of a substantial number of genes related to Wnt signaling and transforming growth factor beta (TGF-β)/(bone morphogenetic protein) BMP signaling pathways between regeneration and cancer. Functional activation of canonical Wnt or TGF-β/BMP pathways during melanocyte regeneration promoted melanocyte regeneration but potently suppressed the invasiveness, migration, and proliferation of human melanoma cells and . Therefore, the opposite regulation of signaling mechanisms between melanocyte regeneration and melanoma can be exploited to stop tumor growth and develop new anti-cancer therapies.
PubMed: 38020918
DOI: 10.3389/fcell.2023.1297910 -
Neuro-oncology Oct 2023Chromosome instability (CIN) with recurrent copy number alterations is a feature of many solid tumors, including glioblastoma (GBM), yet the genes that regulate cell...
BACKGROUND
Chromosome instability (CIN) with recurrent copy number alterations is a feature of many solid tumors, including glioblastoma (GBM), yet the genes that regulate cell division are rarely mutated in cancers. Here, we show that the brain-abundant mitogen, platelet-derived growth factor-A (PDGFA) fails to induce the expression of kinetochore and spindle assembly checkpoint genes leading to defective mitosis in neural progenitor cells (NPCs).
METHODS
Using a recently reported in vitro model of the initiation of high-grade gliomas from murine NPCs, we investigated the immediate effects of PDGFA exposure on the nuclear and mitotic phenotypes and patterns of gene and protein expression in NPCs, a putative GBM cell of origin.
RESULTS
NPCs divided abnormally in defined media containing PDGFA with P53-dependent effects. In wild-type cells, defective mitosis was associated with P53 activation and cell death, but in some null cells, defective mitosis was tolerated. Surviving cells had unstable genomes and proliferated in the presence of PDGFA accumulating random and clonal chromosomal rearrangements. The outcome of this process was a population of tumorigenic NPCs with recurrent gains and losses of chromosomal regions that were syntenic to those recurrently gained and lost in human GBM. By stimulating proliferation without setting the stage for successful mitosis, PDGFA-transformed NPCs lacking P53 function.
CONCLUSIONS
Our work describes a mechanism of transformation of NPCs by a brain-associated mitogen, raising the possibility that the unique genomic architecture of GBM is an adaptation to defective mitosis that ensures the survival of affected cells.
Topics: Humans; Animals; Mice; Mitogens; Tumor Suppressor Protein p53; Mitosis; Neural Stem Cells; Glioblastoma
PubMed: 37186014
DOI: 10.1093/neuonc/noad082