Cell cycle control of β-cell replication in the prenatal and postnatal human pancreas

2011 ◽  
Vol 300 (1) ◽  
pp. E221-E230 ◽  
Author(s):  
Christina U. Köhler ◽  
Marvin Olewinski ◽  
Andrea Tannapfel ◽  
Wolfgang E. Schmidt ◽  
Helga Fritsch ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Regulation ◽  
Cyclin D3 ◽  
Cell Regeneration ◽  
Human Pancreas ◽  
Cell Replication ◽  
Β Cells ◽  
Β Cell ◽  
Cell Cycle Proteins ◽  
Cycle Regulation

β-Cell regeneration declines with aging, but the molecular mechanisms controlling β-cell replication in humans are not well understood. We compared the expression of selected cell cycle proteins in prenatal and adult tissue and examined the association of these proteins with β-cell replication. Pancreatic tissue from a total of 20 human fetuses and adults was stained for Ki67, cyclin D3, p16 and p27, and insulin. The β-cellular expression of these cell cycle proteins was determined. The frequency of β-cell replication was lower in adult compared with prenatal β-cells (<0.5 vs. 3.4 ± 0.5%, respectively; P < 0.0001). p16 was sporadically expressed in prenatal β-cells (8.0 ± 1.1%) but highly enriched in adult β-cells (63.1 ± 5.2%, P < 0.0001). Likewise, the expression of p27 was much lower in prenatal β-cells (1.7 ± 0.4 vs. 44.1 ± 5.4%, respectively, P < 0.0001), and cyclin D3 expression increased from 24.2 ± 4.1 to 47.25 ± 5.0%, respectively ( P < 0.001), with aging. The expression of all three proteins was significantly correlated with each other ( P < 0.01 and r > 0.75, respectively). The strong expression of cyclin D3 in adult human β-cells and its correlation to p27 and p16 suggest a positive role in human β-cell cycle regulation. p16 and p27 appear to restrict β-cell replication with aging. The age dependency of cell cycle regulation in human β-cells might explain the reduced β-cell regeneration in adult humans.

scholarly journals Dynamics of β-cell turnover: evidence for β-cell turnover and regeneration from sources of β-cells other than β-cell replication in the HIP rat

2009 ◽  
Vol 297 (2) ◽  
pp. E323-E330 ◽  
Author(s):  
Erica Manesso ◽  
Gianna M. Toffolo ◽  
Yoshifumi Saisho ◽  
Alexandra E. Butler ◽  
Aleksey V. Matveyenko ◽  
...  
Keyword(s):  
Cell Mass ◽  
Cell Formation ◽  
Cell Regeneration ◽  
Cell Turnover ◽  
Cell Replication ◽  
Wild Type ◽  
Β Cells ◽  
Β Cell ◽  
Islet Amyloid

Type 2 diabetes is characterized by hyperglycemia, a deficit in β-cells, increased β-cell apoptosis, and islet amyloid derived from islet amyloid polypeptide (IAPP). These characteristics are recapitulated in the human IAPP transgenic (HIP) rat. We developed a mathematical model to quantify β-cell turnover and applied it to nondiabetic wild type (WT) vs. HIP rats from age 2 days to 10 mo to establish 1) whether β-cell formation is derived exclusively from β-cell replication, or whether other sources of β-cells (OSB) are present, and 2) to what extent, if any, there is attempted β-cell regeneration in the HIP rat and if this is through β-cell replication or OSB. We conclude that formation and maintenance of adult β-cells depends largely (∼80%) on formation of β-cells independent from β-cell duplication. Moreover, this source adaptively increases in the HIP rat, implying attempted β-cell regeneration that substantially slows loss of β-cell mass.

FLT3/ITD Expression Increases Expansion, Survival and Entry into Cell Cycle of Human Hematopoietic Stem Cells.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 484-484
Author(s):  
Li Li ◽  
Obdulio Piloto ◽  
Kyu-Tae Kim ◽  
Zhaohui Ye ◽  
Bao Nguyen ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Stem Cells ◽  
Tyrosine Kinase ◽  
Cell Cycle Regulation ◽  
Cyclin D3 ◽  
Leukemic Transformation ◽  
Hematopoietic Stem ◽  
Activating Mutations ◽  
Juxtamembrane Region ◽  
Cycle Regulation

Abstract FMS-like tyrosine kinase-3 (FLT3) is a Class III receptor tyrosine kinase that is important for normal hematopoiesis. Activating mutations of FLT3 by internal tandem duplications (ITDs) in the juxtamembrane region are the most common molecular aberrations found in acute myeloid leukemia (AML). The contributions of FLT3 activating mutations in the leukemic transformation of normal human hematopoietic stem/progenitor cells (HSCs) have not yet been fully elucidated. In this study, using a single lentiviral vector containing two promoters, we achieved consistent and efficient coexpression of FLT3/ITD and green fluorescent protein (GFP) in transduced human CD34+ HSCs. When cultured in medium containing SCF, TPO and FLT3 ligand (FL), FLT3/ITD-transduced cells survived with enhanced self-renewal and survival potential, which was not affected by the withdrawal of FL. These cells retained a surface immunophenotype typical of HSCs (CD34+CD38−). Compared to cells transduced with a vector expressing GFP alone, FLT3/ITD-transduced HSCs had a higher fraction of cells in cell cycle. Clonogenic assays showed that FLT3/ITD-transduced HSCs produced fewer CFU-GM, implying that they were at least partially blocked in their ability to differentiate along the myeloid lineage. FLT3/ITD-transduced HSCs were more sensitive to the induction of cytotoxicity by CEP-701, a selective FLT3 inhibitor. In the FLT3/ITD-transduced HSCs, we detected increased expression of Pim-1, a serine/threonine kinase with an important role in cell survival, proliferation and differentiation, c-myc, a transcription factor involved in cell proliferation and cell cycle regulation, and Cyclin D3, a key factor in cell cycle regulation, each of which may contribute to the altered genetic program instituted by FLT3/ITD signaling. These results together indicate that FLT3/ITD mutations may contribute to leukemic transformation of normal HSCs by prolonging survival, promoting proliferation, and blocking differentiation. CEP-701 may act as a potent agent for AML stem cells harboring FLT3/ITD mutations.

The MEIS1 Interactome in Megakaryocytes Reveals a Role in Cell Cycle Regulation,

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3380-3380
Author(s):  
Vishal A Salunkhe ◽  
Iain Macaulay ◽  
Sylvia Nuernberg ◽  
Cathal McCarthy ◽  
Willem Hendrik Ouwehand ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Regulation ◽  
Cell Cycle Progression ◽  
Cyclin D3 ◽  
Haematopoietic Stem Cell ◽  
Nuclear Fraction ◽  
Cell Cycle Regulators ◽  
Cycle Progression ◽  
Cycle Regulation

Abstract Abstract 3380 Haematopoiesis is highly coordinated process of fate determination at branch points that is regulated by transcription factors and their cofactors. Our comprehensive catalogue of transcripts in the eight main mature blood cell elements, including erythroblasts and megakaryocytes (MKs) showed that the transcription factor MEIS1 is uniquely transcribed in MKs and the CD34+ haematopoietic stem cell. Gene silencing studies in mice and zebrafish has shown a pivotal role for MEIS1 in haematopoiesis, megakaryopoiesis and vasculogenesis, although its precise hierarchical position and function remain unknown. To gain further insight in the role of MEIS1 in megakaryopoiesis, we used a proteomics approach to search for its nuclear interaction partners. Co-immunoprecipitation was used to isolate MEIS1 interacting proteins from the nuclear fraction of the MK cell line, CHRF 288–11 and resulting eluates were subjected to proteomics analysis using one-dimensional electrophoresis and liquid chromatography (LC) coupled to tandem mass spectrometry (MS) or GeLC-MS/MS. In total 70 proteins were identified to co-immunoprecipitate with MEIS1 from 3 replicate MS analyses. These included the previously validated MEIS1 interactors PBX1 and HOXB9, as well as numerous novel interactors such as ARID3B and DHX9. Network analysis of our MEIS1 interactome dataset revealed a strong association with cell cycle regulation. In fact, we had identified a myriad of cell cycle regulators including CDK1, CDK2, CDK9, CUL3, PCNA, CDC5L, ARID3B and MDC1. These interactions are consistent with recent microarray studies in promyelocytic leukemic cell lines that link MEIS1 with cell cycle entry and its regulation of genes such as CDK2, CDK6, CDKN3, CDC7 and Cyclin D3 among others. To confirm the novel interaction of MK MEIS1 with cell cycle regulators we performed reverse immuno-precipitation/immunoblot analysis in CHRF cells and purified MEIS1 containing multiprotein complexes from L8057 murine megakaryoblastic cells. Using a cell cycle specific PCR array, we demonstrate that MEIS1 overexpression in L8057 cells regulates numerous cell cycle regulatory genes. Preliminary analysis using flow cytometry demonstrated that MEIS1 overexpression resulted in an altered cell cycle progression. Furthermore, genome wide ChIP-Seq analysis in CHRF cells for MEIS1 revealed binding sites in Cyclin D3 and CDK6, two known key regulators of the cell cycle and megakaryopoiesis. Taken together this study provides evidence linking MEIS1 to the cell cycle control of MKs and will help elucidate the role of MEIS1 in cell cycle progression, megakaryopoiesis and associated disorders. Disclosures: No relevant conflicts of interest to declare.

Rapamycin-induced G1 arrest in cycling B-CLL cells is associated with reduced expression of cyclin D3, cyclin E, cyclin A, and survivin

Blood ◽  
2003 ◽  
Vol 101 (1) ◽  
pp. 278-285 ◽  
Author(s):  
Thomas Decker ◽  
Susanne Hipp ◽  
Ingo Ringshausen ◽  
Christian Bogner ◽  
Madlene Oelsner ◽  
...  
Keyword(s):  
Cell Cycle ◽  
B Cells ◽  
Cell Cycle Regulation ◽  
Cell Cycle Progression ◽  
Cyclin E ◽  
Cyclin A ◽  
Cyclin D3 ◽  
G1 Arrest ◽  
Cycle Progression ◽  
Cycle Regulation

Abstract In B-cell chronic lymphocytic leukemia (B-CLL), malignant cells seem to be arrested in the G0/early G1phase of the cell cycle, and defective apoptosis might be involved in disease progression. However, increasing evidence exists that B-CLL is more than a disease consisting of slowly accumulating resting B cells: a proliferating pool of cells has been described in lymph nodes and bone marrow and might feed the accumulating pool in the blood. Rapamycin has been reported to inhibit cell cycle progression in a variety of cell types, including human B cells, and has shown activity against a broad range of human tumor cell lines. Therefore, we investigated the ability of rapamycin to block cell cycle progression in proliferating B-CLL cells. We have recently demonstrated that stimulation with CpG-oligonucleotides and interleukin-2 provides a valuable model for studying cell cycle regulation in malignant B cells. In our present study, we demonstrated that rapamycin induced cell cycle arrest in proliferating B-CLL cells and inhibited phosphorylation of p70s6 kinase (p70s6k). In contrast to previous reports on nonmalignant B cells, the expression of the cell cycle inhibitor p27 was not changed in rapamycin-treated leukemic cells. Treatment with rapamycin prevented retinoblastoma protein (RB) phosphorylation in B-CLL cells without affecting the expression of cyclin D2, but cyclin D3 was no longer detectable in rapamycin-treated B-CLL cells. In addition, rapamycin treatment inhibited cyclin-dependent kinase 2 activity by preventing up-regulation of cyclin E and cyclin A. Interestingly, survivin, which is expressed in the proliferation centers of B-CLL patients in vivo, is not up-regulated in rapamycin-treated cells. Therefore, rapamycin interferes with the expression of many critical molecules for cell cycle regulation in cycling B-CLL cells. We conclude from our study that rapamycin might be an attractive substance for therapy for B-CLL patients by inducing a G1 arrest in proliferating tumor cells.

scholarly journals cMyc Is a Principal Upstream Driver of β-Cell Proliferation in Rat Insulinoma Cell Lines and Is an Effective Mediator of Human β-Cell Replication

2011 ◽  
Vol 25 (10) ◽  
pp. 1760-1772 ◽  
Author(s):  
Esra Karslioglu ◽  
Jeffrey W. Kleinberger ◽  
Fatimah G. Salim ◽  
Amy E. Cox ◽  
Karen K. Takane ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Cell Death ◽  
Cell Lines ◽  
Cell Cycle Control ◽  
Diabetes Research ◽  
Cell Replication ◽  
Β Cells ◽  
Β Cell ◽  
Normal Rat

Adult human β-cells replicate slowly. Also, despite the abundance of rodent β-cell lines, there are no human β-cell lines for diabetes research or therapy. Prior studies in four commonly studied rodent β-cell lines revealed that all four lines displayed an unusual, but strongly reproducible, cell cycle signature: an increase in seven G1/S molecules, i.e. cyclins A, D3, and E, and cdk1, -2, -4, and -6. Here, we explore the upstream mechanism(s) that drive these cell cycle changes. Using biochemical, pharmacological and molecular approaches, we surveyed potential upstream mitogenic signaling pathways in Ins 1 and RIN cells. We used both underexpression and overexpression to assess effects on rat and human β-cell proliferation, survival and cell cycle control. Our results indicate that cMyc is: 1) uniquely up-regulated among other candidates; 2) principally responsible for the increase in the seven G1/S molecules; and, 3) largely responsible for proliferation in rat β-cell lines. Importantly, cMyc expression in β-cell lines, although some 5- to 7-fold higher than normal rat β-cells, is far below the levels (75- to 150-fold) previously associated with β-cell death and dedifferentiation. Notably, modest overexpression of cMyc is able to drive proliferation without cell death in normal rat and human β-cells. We conclude that cMyc is an important driver of replication in the two most commonly employed rat β-cell lines. These studies reverse the current paradigm in which cMyc overexpression is inevitably associated with β-cell death and dedifferentiation. The cMyc pathway provides potential approaches, targets, and tools for driving and sustaining human β-cell replication.

scholarly journals Translational repression of cyclin D3 by a stable G-quadruplex in its 5′ UTR: implications for cell cycle regulation

RNA Biology ◽  
2012 ◽  
Vol 9 (8) ◽  
pp. 1099-1109 ◽  
Author(s):  
Heng-You Weng ◽  
Hui-Lin Huang ◽  
Pan-Pan Zhao ◽  
Hui Zhou ◽  
Liang-Hu Qu
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Regulation ◽  
Cyclin D3 ◽  
Translational Repression ◽  
G Quadruplex ◽  
Cycle Regulation

scholarly journals Cell Cycle Regulation of the Pdx1 Transcription Factor in Developing Pancreas and Insulin-Producing β Cells

Diabetes ◽  
2021 ◽  
pp. db200599
Author(s):  
Xiaogdong Zhu ◽  
Alexis Oguh ◽  
Morgan A. Gingerich ◽  
Scott A. Soleimanpour ◽  
Doris A. Stoffers ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Transcription Factor ◽  
Cell Cycle Regulation ◽  
Β Cells ◽  
Cycle Regulation

scholarly journals Development of a reliable automated screening system to identify small molecules and biologics that promote human β-cell regeneration

2016 ◽  
Vol 311 (5) ◽  
pp. E859-E868 ◽  
Author(s):  
Kristie I. Aamodt ◽  
Radhika Aramandla ◽  
Judy J. Brown ◽  
Nathalie Fiaschi-Taesch ◽  
Peng Wang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Cyclin D3 ◽  
Cell Counting ◽  
Cell Cycle Regulators ◽  
Β Cells ◽  
Β Cell ◽  
Ki 67 ◽  
Proliferation Markers

Numerous compounds stimulate rodent β-cell proliferation; however, translating these findings to human β-cells remains a challenge. To examine human β-cell proliferation in response to such compounds, we developed a medium-throughput in vitro method of quantifying adult human β-cell proliferation markers. This method is based on high-content imaging of dispersed islet cells seeded in 384-well plates and automated cell counting that identifies fluorescently labeled β-cells with high specificity using both nuclear and cytoplasmic markers. β-Cells from each donor were assessed for their function and ability to enter the cell cycle by cotransduction with adenoviruses encoding cell cycle regulators cdk6 and cyclin D3. Using this approach, we tested 12 previously identified mitogens, including neurotransmitters, hormones, growth factors, and molecules, involved in adenosine and Tgf-1β signaling. Each compound was tested in a wide concentration range either in the presence of basal (5 mM) or high (11 mM) glucose. Treatment with the control compound harmine, a Dyrk1a inhibitor, led to a significant increase in Ki-67+ β-cells, whereas treatment with other compounds had limited to no effect on human β-cell proliferation. This new scalable approach reduces the time and effort required for sensitive and specific evaluation of human β-cell proliferation, thus allowing for increased testing of candidate human β-cell mitogens.

scholarly journals Overexpression of Hepatocyte Nuclear Factor-4α Initiates Cell Cycle Entry, but Is not Sufficient to Promote β-Cell Expansion in Human Islets

2012 ◽  
Vol 26 (9) ◽  
pp. 1590-1602 ◽  
Author(s):  
Sebastian Rieck ◽  
Jia Zhang ◽  
Zhaoyu Li ◽  
Chengyang Liu ◽  
Ali Naji ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Dna Damage ◽  
Human Islets ◽  
Cyclin D3 ◽  
Hepatocyte Nuclear Factor ◽  
Β Cells ◽  
Β Cell ◽  
Cell Cycle Entry ◽  
Damage Response ◽  
Hepatocyte Nuclear Factor 4Α

Abstract The transcription factor HNF4α (hepatocyte nuclear factor-4α) is required for increased β-cell proliferation during metabolic stress in vivo. We hypothesized that HNF4α could induce proliferation of human β-cells. We employed adenoviral-mediated overexpression of an isoform of HNF4α (HNF4α8) alone, or in combination with cyclin-dependent kinase (Cdk)6 and Cyclin D3, in human islets. Heightened HNF4α8 expression led to a 300-fold increase in the number of β-cells in early S-phase. When we overexpressed HNF4α8 together with Cdk6 and Cyclin D3, β-cell cycle entry was increased even further. However, the punctate manner of bromodeoxyuridine incorporation into HNF4αHigh β-cells indicated an uncoupling of the mechanisms that control the concise timing and execution of each cell cycle phase. Indeed, in HNF4α8-induced bromodeoxyuridine+,punctate β-cells we observed signs of dysregulated DNA synthesis, cell cycle arrest, and activation of a double stranded DNA damage-associated cell cycle checkpoint mechanism, leading to the initiation of loss of β-cell lineage fidelity. However, a substantial proportion of β-cells stimulated to enter the cell cycle by Cdk6 and Cyclin D3 alone also exhibited a DNA damage response. HNF4α8 is a mitogenic signal in the human β-cell but is not sufficient for completion of the cell cycle. The DNA damage response is a barrier to efficient β-cell proliferation in vitro, and we suggest its evaluation in all attempts to stimulate β-cell replication as an approach to diabetes treatment.

Sign in / Sign up

Export Citation Format

Share Document