A TET1-PSPC1-Neat1 molecular axis modulates PRC2 functions in controlling stem cell bivalency

SUMMARYTET1 maintains hypomethylation at bivalent promoters through its catalytic activity in embryonic stem cells (ESCs). However, whether and how TET1 exerts catalytic activity-independent functions in regulating bivalent genes is not well understood. Using a proteomics approach, we mapped the TET1 interactome in mouse ESCs and identified PSPC1 as a novel TET1 partner. Genome-wide location analysis reveals that PSPC1 functionally associates with TET1 and Polycomb repressive complex-2 (PRC2) complex. We establish that PSPC1 and TET1 repress, and Neat1, the PSPC1 cognate lncRNA, activates the bivalent gene expression. In ESCs, Neat1 tethers the TET1-PSPC1 pair with PRC2 at bivalent promoters. During the ESC-to-formative epiblast-like stem cell (EpiLC) transition, PSPC1 and TET1 promote PRC2 chromatin occupancy at bivalent gene promoters while restricting Neat1 functions in facilitating PRC2 binding to bivalent gene transcripts. Our study uncovers a novel TET1-PSPC1-Neat1 molecular axis that modulates PRC2 binding affinity to chromatin and bivalent gene transcripts in controlling stem cell bivalency.In BriefTET1 is a transcriptional repressor for bivalent genes in pluripotent stem cells, but its mechanistic action on stem cell bivalency is unclear. Huang et al. use proteomics and genetic approaches to reveal that catalytic activity-independent functions of TET1, coordinated with the paraspeckle components PSPC1 and its cognate lncRNA Neat1, dynamically regulates stem cell bivalency by modulating PRC2 binding affinity to chromatin and bivalent gene transcripts in pluripotent state transition.HighlightsThe TET1 interactome identifies PSPC1 as a novel partner in ESCsTET1 and PSPC1 repress bivalent genes by promoting PRC2 chromatin occupancyNeat1 facilitates bivalent gene activation by promoting PRC2 binding to their mRNAsNeat1 bridges the TET1-PSPC1 and PRC2 complexes in regulating bivalent gene transcription

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MiR-146a-dependent regulation of CD24/AKT/β-catenin axis drives cancer stem cell phenotype in oral squamous cell carcinoma

10.1101/429068 ◽

2018 ◽

Cited By ~ 1

Author(s):

Sangeeta Ghuwalewala ◽

Dishari Ghatak ◽

Sumit Das ◽

Pijush Das ◽

Ramesh Butti ◽

...

Keyword(s):

Stem Cells ◽

Squamous Cell Carcinoma ◽

Stem Cell ◽

Oral Squamous Cell Carcinoma ◽

Cancer Stem Cell ◽

Cell Carcinoma ◽

Squamous Cell ◽

Cell Phenotype ◽

List Type

AbstractCancer stem cells (CSCs) are known to potentiate tumor initiation and maintenance in Oral Squamous Cell Carcinoma (OSCC). Increasing evidences suggest that CD44highCD24low population in OSCC are potential CSCs. MicroRNAs (miRNAs) have emerged as crucial players in tumor development. However, their role in maintenance of OSCC stem cells remains unclear. Here we report that CD44highCD24low population within OSCC cells and primary HNSCC tumors have an elevated expression of miR-146a. Moreover, over-expression of miR-146a results in enhanced stemness phenotype by augmenting CD44highCD24low population. We demonstrate that miR-146a induces stemness by stabilizing β-catenin with concomitant loss of E-cadherin and CD24. Interestingly, CD24 is identified as a novel functional target of miR-146a and ectopic expression of CD24 abrogates miR-146a driven potential CSC phenotype. Mechanistic analysis reveals that higher CD24 levels inhibit AKT phosphorylation leading to β-catenin degradation. Using stably expressing miR-146a/CD24 OSCC cell lines, we also validate that the miR-146a/ CD24/AKT loop significantly alters tumorigenic ability in vivo. Furthermore, we confirmed that β-catenin trans-activates miR-146a, thereby forming a positive feedback loop contributing to stem cell maintenance. Collectively, our study demonstrates that miR-146a regulate CSCs in OSCC through CD24-AKT-β-catenin axis.HighlightsMiR-146a induces cancer stem cell characteristics in OSCC by targeting CD24CD24 abrogates miR-146a mediated stemness via β-catenin degradation in non-CSCsAkt/Wnt pathway is critical for sustenance of miR-146a driven potential CSCsThe miR-146a/CD24/AKT loop significantly alters tumorigenic ability in vivo

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CDK6 Antagonizes TP53-Induced Responses during Tumorigenesis

Blood ◽

10.1182/blood-2019-121101 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. SCI-15-SCI-15

Author(s):

Veronika Sexl ◽

Karoline Kollmann ◽

Florian Bellutti

Keyword(s):

Cell Cycle ◽

Stem Cells ◽

Stem Cell ◽

Transcription Factors ◽

Conflicts Of Interest ◽

Induced Responses ◽

Hematopoietic Stem ◽

Hematopoietic Malignancies ◽

Independent Functions ◽

Oncogenic Stress

Inhibitors directed against cyclin dependent kinases (CDKs) have raised much interest as anti-cancer therapeutics over the last years. In particular, inhibitors directed against CDK4/6 have been declared as a major breakthrough in cancer therapy by the FDA. CDK4 and CDK6 bind to D-type cyclins and subsequently phosphorylate the RB protein to allow cells to progress through the G1 phase of the cell cycle. The effectiveness of CDK4/6 inhibitors was primarily assigned to their ability to block cell cycle progression. In hematopoietic malignancies high levels of CDK6, but not CDK4, are frequently found. Over the last years we have assigned a novel and unexpected role for CDK6 as global transcriptional regulator. ChIP-Seq experiments identified more than 20.000 specific CDK6 binding sites in leukemic cells with the majority located in the promoter regions. CDK6 binding to chromatin does not require kinase activity whereas transcriptional control is regulated in a kinase- dependent as well as kinase-independent manner. Overlaying ChIP-Seq and RNA-Seq experiments showed that CDK6 contributes to the induction or repression of genes. Target genes of CDK6 which are important for leukemia progression include PIM1, c-MYC, AURKA, AURKB, AKT and VEGF-A. Murine leukemia models verified the importance of CDK6 for myeloid and lymphoid tumor formation downstream of a variety of oncogenes including FLT3-ITD, NPM/ALK, MLL/AF9, BCR/ABL or JAK2V617F. CDK6 contributes to disease development by regulating proliferation, cell survival, angiogenesis and cytokine production. In hematopoietic stem cells and leukemic stem cells kinase-independent functions dominate and CDK6 controls a network of transcription factors regulating stem cell quiescence and activation. The importance of kinase-dependent transcriptional effects is pronounced under conditions of stress and transformation. Upon oncogenic stress, CDK6 induces a set of genes that counteract pro-apoptotic TP53 responses including MDM4, PRMT5, PPM1D and BCL2. This response is induced by a CDK6 - dependent phosphorylation of the transcription factors SP1 and NFYA as verified by phospho-chromatome analysis. Murine Cdk6-deficient cells only survive oncogenic stress by mutating Tp53. The link between CDK6 and TP53 is conserved in human hematopoietic malignancies. Kollmann K, Heller G, Schneckenleithner C, et al. A kinase-independent function of CDK6 links the cell cycle to tumor angiogenesis. Cancer Cell. 2013;24(2):167-181.Scheicher R, Hoelbl-Kovacic A, Bellutti F, et al. CDK6 as a key regulator of hematopoietic and leukemic stem cell activation. Blood. 2015;125(1):90-101.Uras IZ, Walter GJ, Scheicher R, et al. Palbociclib treatment of FLT3-ITD+ AML cells uncovers a kinase-dependent transcriptional regulation of FLT3 and PIM1 by CDK6. Blood. 2016;127(23):2890-2902.Bellutti F, Tigan AS, Nebenfuehr S, et al. CDK6 antagonizes P53-induced responses during tumorigenesis. Cancer Discov. 2018;8(7):884-897.Uras IZ, Maurer B, Nivarthi H, et al. CDK6 coordinates JAK2V617F mutant MPN via NF-kB and apoptotic networks. Blood. 2019;133(15):1677-1690. Disclosures No relevant conflicts of interest to declare.

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Bivalent chromatin protects reversibly repressed genes from irreversible silencing

10.1101/2020.12.02.406751 ◽

2020 ◽

Author(s):

Dhirendra Kumar ◽

Raja Jothi

Keyword(s):

Dna Methylation ◽

Regulatory Mechanism ◽

De Novo ◽

Embryonic Stem ◽

Cell Types ◽

List Type ◽

Gene Promoters ◽

Dna Hypermethylation ◽

Rapid Activation ◽

Bivalent Gene

ABSTRACTBivalent chromatin is characterized by the simultaneous presence of H3K4me3 and H3K27me3, histone modifications generally associated with transcriptionally active and repressed chromatin, respectively. Prevalent in embryonic stem cells, bivalency is postulated to poise lineage-controlling developmental genes for rapid activation during embryogenesis while maintaining a transcriptionally repressed state in the absence of activation cues, but its function in development and disease remains a mystery. Here we show that bivalency does not poise genes for rapid activation but protects reversibly repressed genes from irreversible silencing. We find that H3K4me3 at bivalent gene promoters—a product of the underlying DNA sequence—persists in nearly all cell types irrespective of gene expression and confers protection from de novo DNA methylation. Accordingly, loss of H3K4me3 at bivalent promoters is strongly associated with aberrant hypermethylation and irreversible silencing in adult human cancers. Bivalency may thus represent a distinct regulatory mechanism for maintaining epigenetic plasticity.HIGHLIGHTSBivalent chromatin does not poise genes for rapid activationH3K4me3 at bivalent promoters is not instructive for transcription activationH3K4me3 at bivalent promoters protects reversibly repressed genes from de novo DNA methylationLoss of H3K4me3/bivalency is associated with aberrant DNA hypermethylation in cancer

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The hematopoietic landscape at single-cell resolution reveals unexpected stem cell features in naked mole-rats

10.1101/859454 ◽

2019 ◽

Author(s):

Stephan Emmrich ◽

Marco Mariotti ◽

Masaki Takasugi ◽

Maggie E. Straight ◽

Alexandre Trapp ◽

...

Keyword(s):

Stem Cells ◽

T Cells ◽

Stem Cell ◽

Single Cell ◽

Cell Biology ◽

List Type ◽

Hematopoietic Stem ◽

Age Related ◽

Mole Rat ◽

Naked Mole Rat

SUMMARYNaked mole-rats are the longest-lived rodents endowed with resistance to cancer and age-related diseases, yet their stem cell characteristics remain enigmatic. We profiled the naked mole-rat hematopoietic system down to single-cell resolution, and identified several unique features likely contributing to longevity. In adult naked mole-rats red blood cells are formed in spleen and marrow, a neotenic feature beneficial for hypoxic environments and to prevent anemia. Platelet numbers are lower compared to short-lived mice, which may preclude age-related platelet increase and thrombosis. T cells mature in thymus and lymph nodes, providing a supply of T cells after age-related thymus involution. The pool of quiescent stem cells is higher than in mice, and HSCs overexpress an oxidative phosphorylation signature, revealing a new paradigm of stem cell metabolism to benefit longevity and oppose oncogenesis. Our work provides a platform to study immunology and stem cell biology in an animal model of healthy aging.HIGHLIGHTSFlow cytometry labelling panel to purify viable naked mole-rat HSPCsThe spleen as the major site of erythropoiesis in the naked mole-ratNaked mole-rats show extrathymic T-cell development under homeostatic conditionsNaked mole-rat hematopoietic stem cells (HSCs) have high OXPHOS activity

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Renal Involvement in Patients with COVID-19 Pneumonia and Outcomes After Stem Cell Nebulization

10.1101/2020.12.16.20236877 ◽

2020 ◽

Author(s):

Gina M. Torres Zambrano ◽

Carlos A. Villegas Valverde ◽

Antonio Bencomo Hernández ◽

Lobna Abdel Hadi ◽

Rene Antonio Rivero ◽

...

Keyword(s):

Clinical Trial ◽

Stem Cells ◽

Stem Cell ◽

Hospital Stay ◽

Treated Group ◽

Abu Dhabi ◽

Great Promise ◽

List Type ◽

Early Recovery ◽

The Impact

ABSTRACTBackgroundThe COVID-19 pandemic presented an unprecedented challenge to identify effective drugs for prevention and treatment.ObjectiveTo characterize acute renal injury (AKI) in patients with COVID-19 and their relation with clinical outcomes within the framework of the SENTAD COVID clinical trial at the Abu Dhabi Stem Cells Center.MethodsAbu Dhabi Stem Cell Center (ADSCC) proposed a prospective clinical trial nebulization treatment with autologous stem cells (Non-Hematopoietic Peripheral Blood Stem Cells (NHPBSC)), at Abu Dhabi hospitals.Participants20 treated patients were compared with 23 not treated patients. Both groups received COVID 19 standard treatment.OutcomesAfter the results were collected, this study was created to determine the impact of the disease on the renal function and the efficacy of the therapy on patient’s outcomes.ResultsOne third of the critical patients studied suffered kidney failure. Patients in the treated group showed a favorable tendency to improve in contrast to those in the control group. Less patients from group A suffered from sepsis in comparison with the group B (25% vs 65%), HR=0.38, (95% Confidence Interval: 0.16 – 0.86), *p=0.0212. These results suggested a NNT=2.5. An improvement in lymphocyte count, CRP, and shorter hospital stay after treatment was evidenced, which led to less superinfection and sepsis in the treated group.ConclusionsThe proposed anti-inflammatory effect of the stem cells, offers a great promise for managing the illness, emerging as a crucial adjuvant tool in promoting healing and early recovery in severe COVID-19 infections and other supportive treatments.ARTICLE SUMMARYOur study had several strengths and limitation: It was a randomized trial.The treatment showed a positive result, providing evidence that this intervention is effective in routine practice.We found fewer complications related to prolonged hospital stay in the treated group.The is the small number of participants.It was carried out in 4 different hospitals, each with different criteria for the selection of the initial empirical antimicrobials, which can cause multiple resistant germs.

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ZFP982 confers mouse embryonic stem cell characteristics by regulating expression of Nanog, Zfp42 and Dppa3

10.1101/2020.06.03.131847 ◽

2020 ◽

Author(s):

Fariba Dehghanian ◽

Patrick Piero Bovio ◽

Zohreh Hojati ◽

Tanja Vogel

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Embryonic Stem Cells ◽

Neural Differentiation ◽

Marker Gene ◽

Embryonic Stem ◽

Mouse Embryonic Stem Cells ◽

Stem Cell Marker ◽

Marker Genes ◽

List Type

AbstractWe here used multi-omics analyses to identify and characterize zinc finger protein 982 (Zfp982) that confers stemness characteristics by regulating expression of Nanog, Zfp42 and Dppa3 in mouse embryonic stem cells (mESC). Network-based expression analyses comparing the transcriptional profiles of mESC and differentiated cells revealed high expression of Zfp982 in stem cells. Moreover, Zfp982 showed transcriptional overlap with Yap1, the major co-activator of the Hippo pathway. Quantitative proteomics and co-immunoprecipitation revealed interaction of ZFP982 with YAP1. ZFP982 used a GCAGAGKC motif to bind to chromatin, for example near the stemness conferring genes Nanog, Zfp42 and Dppa3 as shown by ChIP-seq. Loss-of-function experiments in mESC established that expression of Zfp982 is necessary to maintain stem cell characteristics. Zfp982 expression decreased with progressive differentiation, and knockdown of Zfp982 resulted in neural differentiation of mESC. ZFP982 localized to the nucleus in mESC and translocated to the cytoplasm upon neuronal differentiation. Similarly, YAP1 localized to the cytoplasm upon differentiation, but in mESC YAP1 was present in the nucleus and cytoplasm.Graphical AbstractZFP982 is a regulator of stemness of mouse embryonic stem cells and acts as transcription factor by activating expression of stem cell genes including Nanog, Dppa3 and Zfp42.HighlightsZfp982 is a new mouse stem cell defining marker gene.Zfp982 is co-expressed with Yap1 and stem cell marker genes in mESC.ZFP982 binds to DNA and induces expression of master genes of stemness in mESC.Expression of Zfp982 gene prevents neural differentiation and maintains stem cell characteristics.ZFP982 and YAP1 interact in mESC and translocate to the cytoplasm upon neural differentiation.

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microRNAs (miR 9, 124, 155 and 224) transdifferentiate macrophages to neurons

10.1101/2020.07.19.210633 ◽

2020 ◽

Author(s):

Naveen Challagundla ◽

Reena Agrawal-Rajput

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Transcription Factors ◽

Neuronal Differentiation ◽

Mononuclear Cells ◽

Neuronal Cells ◽

Cellular Reprogramming ◽

Intermediate Phenotype ◽

List Type ◽

Pluripotency Genes

AbstractDevelopment is an irreversible process of differentiating the undifferentiated cells to functional cells. Brain development involves generation of cells with varied phenotype and functions, which is limited during adulthood, stress, damage/degeneration. Cellular reprogramming makes differentiation reversible process with reprogramming somatic/stem cells to alternative fate with/without stem cells. Exogenously expressed transcription factors or small molecule inhibitors have driven reprogramming of stem/somatic cells to neurons providing alternative approach for pre-clinical/clinical testing and therapeutics. Here in, we report a novel approach of microRNA (miR)-induced trans-differentiation of macrophages (CD11b high) to induced neuronal cells (iNCs) (neuronal markers high-Nestin, Nurr1, Map2, NSE, Tubb3 and Mash1) without exogenous use of transcription factors. miR 9, 124, 155 and 224 successfully transdifferentiated macrophages to neurons with transient stem cell-like phenotype. We report trans differentiation efficacy 18% and 21% with miR 124 and miR 155. in silico (String 10.0, miR gator, mESAdb, TargetScan 7.0) and experimental analysis indicate that the reprogramming involves alteration of pluripotency genes like Oct4, Sox2, Klf4, Nanog and pluripotency miR, miR 302. iNCs also shifted to G0 phase indicating manipulation of cell cycle by these miRs. Further, CD133+ intermediate cells obtained during current protocol could be differentiated to iNCs using miRs. The syanpsin+ neurons were functionally active and displayed intracellular Ca+2 evoke on activation. miRs could also transdifferentiate bone marrow-derived macrophages and peripheral blood mononuclear cells to neuronal cells. The current protocol could be employed for direct in vivo reprogramming of macrophages to neurons without teratoma formation for transplantation and clinical studies.HighlightsmiR 9, miR 124 and miR155 could reprogramme macrophages to mature neurons.miR-induced neuronal reprogramming involves stem cell like intermediate phenotype.Graphical AbstractMacrophages transfected with miR 9, 124, 155 and 224 alter pluripotency genes and neuronal differentiation genes via various mechanisms as elucidated. NIM components may also manipulate driving neuronal differentiation gene expression inducing formation of neuronal cells.

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Cell cycle lengths of stem cells and their lineage from cellular demography

10.1101/2020.11.18.388314 ◽

2020 ◽

Author(s):

Purna Gadre ◽

Nitin Nitsure ◽

Debasmita Mazumdar ◽

Samir Gupta ◽

Krishanu Ray

Keyword(s):

Cell Cycle ◽

Stem Cells ◽

Stem Cell ◽

Fold Increase ◽

Tissue Homeostasis ◽

Fine Tuning ◽

List Type ◽

Germline Stem Cells ◽

Stem Cell Divisions ◽

Cycle Lengths

AbstractAdult stem cells and their transit-amplifying (TA) progeny dynamically alter their proliferation rates to maintain tissue homeostasis. To test how the division rates of stem cell and TA cells affect tissue growth and differentiation, we developed a computation strategy which estimates the average cell cycle lengths/lifespans of germline stem cells (GSCs) and their TA progeny from cellular demography. Analysis of the wild-type data from Drosophila testis using this method indicated anomalous changes in lifespans during the germline transit-amplification with a nearly 1.3-fold increase after the first division and about a 2-fold decrease in the subsequent stage. Genetic perturbations altering the cell cycle rates of GSC and its immediate daughter, the gonialblast (GB), proportionately changed the rates of subsequent TA divisions. Notably, a nearly 2-fold increase or decrease in the total TA duration did not alter the induction of meiosis after four mitotic cycles. Altogether, these results suggest that the rates of GSC and GB divisions can adjust the rates of subsequent divisions and the onset of differentiation.Significance StatementDynamic regulation of the proliferation rate of stem cells and their transit-amplifying daughters maintains tissue homeostasis in different conditions such as tissue regeneration, aging, and hormonal imbalance. Previous studies suggested that a molecular clock in the stem cell progeny determines the timing of differentiation. This work shows that alterations of the rates of stem cell divisions, as well as that of its progeny, could override the differentiation clock in the Drosophila testis, and highlights a possible mechanism of fine-tuning the transit-amplification program under different conditions such as tissue damage, aging, and hormonal inputs. Also, the method developed for this study could be adapted to estimate lineage expansion plasticity from demographic changes in other systems.HighlightsDetermination of cellular lifespan during transit-amplification from demographyLifespans of Drosophila male germline cells changes anomalously during the TALifespan changes of germline stem cells readjust that of the progeny cellsAnomalous lifespan expansion midway through TA precedes the Bam onset

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Hematopoietic Stem Cell Applications: Past, Present and Future

Journal of Postgraduate Medicine Education and Research ◽

10.5005/jp-journals-10028-1016 ◽

2012 ◽

Vol 46 (2) ◽

pp. 69-74

Author(s):

Subhash Varma ◽

Deepesh P Lad ◽

Pankaj Malhotra

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Hematopoietic Stem Cell Transplantation ◽

Stem Cell Transplantation ◽

Hematopoietic Stem Cells ◽

Cell Transplantation ◽

Hematopoietic Stem Cell ◽

Umbilical Cord ◽

List Type ◽

Hematopoietic Stem

ABSTRACT Hematopoietic stem cells have been at the forefront of stem cell research and its applications. Several advancements have occurred in the field of hematopoietic stem cell transplantation since this was first accepted as a treatment for otherwise incurable hematological disorders. The progress in this field is to the extent that it is unfathomable to a single person be it a scientific researcher or a practicing clinician. In this internet era, most patients are also well informed of the utility of stem cells. There is a need to bridge the gap in knowledge of this science between the scientists, physicians and the public at large. This review aims to summarize the advances in hematopoietic stem cell applications. Key messages Hematopoietic stem cells possess the characteristics of self renewal, differentiation, mobilization and apoptosis. The transfer of hematopoietic stem cells to rescue a recipient's hematopoiesis, who has received conditioning with high dose chemotherapy and/or total body irradiation, constitutes hematopoietic stem cell transplantation (HSCT). Hematopoietic stem cells can be obtained from the bone marrow, peripheral blood or umbilical cord blood. Autologous HSCT involves the infusion of one's own hematopoietic stem cells. An allogeneic HSCT involves the infusion of hematopoietic stem cells from another individual. Depending on the HLA match, the HSCT is of following types: Syngeneic, matched related, matched unrelated and haploidentical. Patient selection and the timing of transplant are the most important factors determining transplant outcomes. Hematopoietic stem cells and umbilical cord stem cells have applications in regenerative medicine as shown in preclinical and early clinical studies. How to cite this article Lad DP, Malhotra P, Varma S. Hematopoietic Stem Cell Applications: Past, Present and Future. J Postgrad Med Edu Res 2012;46(2):69-74.

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Laterally confined growth of cells induces nuclear reprogramming in the absence of exogenous biochemical factors

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1714770115 ◽

2018 ◽

Vol 115 (21) ◽

pp. E4741-E4750 ◽

Cited By ~ 21

Author(s):

Bibhas Roy ◽

Saradha Venkatachalapathy ◽

Prasuna Ratna ◽

Yejun Wang ◽

Doorgesh Sharma Jokhun ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

High Efficiency ◽

Somatic Cells ◽

Time Lapse ◽

Nuclear Reprogramming ◽

Sequencing Analysis ◽

Gene Promoters ◽

Mcf7 Cells ◽

Confined Growth

Cells in tissues undergo transdifferentiation programs when stimulated by specific mechanical and biochemical signals. While seminal studies have demonstrated that exogenous biochemical factors can reprogram somatic cells into pluripotent stem cells, the critical roles played by mechanical signals in such reprogramming process have not been well documented. In this paper, we show that laterally confined growth of fibroblasts on micropatterned substrates induces nuclear reprogramming with high efficiency in the absence of any exogenous reprogramming factors. We provide compelling evidence on the induction of stem cell-like properties using alkaline phosphatase assays and expression of pluripotent markers. Early onset of reprogramming was accompanied with enhanced nuclear dynamics and changes in chromosome intermingling degrees, potentially facilitating rewiring of the genome. Time-lapse analysis of promoter occupancy by immunoprecipitation of H3K9Ac chromatin fragments revealed that epithelial, proliferative, and reprogramming gene promoters were progressively acetylated, while mesenchymal promoters were deacetylated by 10 days. Consistently, RNA sequencing analysis showed a systematic progression from mesenchymal to stem cell transcriptome, highlighting pathways involving mechanisms underlying nuclear reprogramming. We then demonstrated that these mechanically reprogrammed cells could be maintained as stem cells and can be redifferentiated into multiple lineages with high efficiency. Importantly, we also demonstrate the induction of cancer stemness properties in MCF7 cells grown in such laterally confined conditions. Collectively, our results highlight an important generic property of somatic cells that, when grown in laterally confined conditions, acquire stemness. Such mechanical reprogramming of somatic cells demonstrated here has important implications in tissue regeneration and disease models.

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