BMS-214662 Targets Quiescent Chronic Myeloid Leukaemia Stem Cells and Enhances the Activity of Both Imatinib and Dasatinib (BMS-354825).

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 693-693 ◽  
Author(s):  
Mhairi Copland ◽  
Ashley Hamilton ◽  
Elaine K. Allan ◽  
Valerie Brunton ◽  
Tessa L. Holyoake
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Chronic Myeloid Leukaemia ◽  
Myeloid Leukaemia ◽  
Caspase 3 ◽  
Kinase Activity ◽  
Drug Control ◽  
Abl Kinase ◽  
Viable Cells

Abstract Chronic myeloid leukaemia (CML) is a clonal disease of stem cell origin associated with expression of the Philadelphia chromosome and its oncogenic fusion protein product Bcr-Abl. Despite an impressive rate of complete cytogenetic response in chronic phase CML, the majority of patients treated with imatinib mesylate (IM) show persistent molecular disease. Recent work by our group shows that this molecular persistence results from a population of quiescent CML stem cells which are not effectively targeted by IM, the novel, oral, multi-targeted kinase inhibitor dasatinib (BMS-354825; which targets Bcr-Abl and Src kinases), or several rationally designed drug combinations1. Further in vitro studies by our group have demonstrated that the only combination to have an improved response in the quiescent stem cell sub-population was IM with the farnesyl transferase inhibitor (FTI) lonafarnib. BMS-214662 is an atypical non-peptidomimetic cytotoxic FTI, which has been shown to preferentially kill non-dividing cells2 and has anti-leukaemic activity in acute myeloid leukaemia. We assessed the efficacy of this compound alone and in combination with IM and dasatinib in primary CD34+ CML cells in vitro using a CFSE-based flow cytometry method to track cell division, caspase-3 activity to measure apoptosis and dephosphorylation of Crkl to determine Bcr-Abl kinase activity. Primary CD34+ CML cells were cultured for 6 days in serum free medium supplemented with 5 growth factors (IL-3, IL-6, Flt-3 ligand, G-CSF and SCF). Conditions studied were: (1) no drug control, (2) IM (5μM; ~IC90 dose), (3) dasatinib (150nM; ~IC90 dose) (4) BMS-214662 (250nM; ~IC50 dose), (5) IM plus BMS-214662, (6) dasatinib plus BMS-214662. After 6 days culture, there was a significant reduction in total viable cells in all treatment arms relative to the no drug control (P=0.001). The combinations of IM plus BMS-214662 and dasatinib plus BMS-214662 showed increased cytotoxic effect over either IM or dasatinib alone (P=0.024 and P=0.034, respectively). While the IM and dasatinib arms showed significant accumulation of undivided CFSEmax CD34+ CML cells over the no drug control (P=0.04 and P=0.023, respectively), the arms containing BMS-214662 either alone or in combination showed a reduction in these primitive cells to <50% of the no drug control. This reduction was highly statistically significant when either IM or dasatinib alone was compared to the combination with BMS-214662 (P=0.01 and P=0.043, respectively). There were no significant differences in undivided CFSEmax CD34+ CML cells between the BMS-214662 containing arms. At 72 hours, caspase-3 activity was increased in the BMS-214662-containing arms with increased apoptosis in the undivided CFSEmax CD34+ CML cells. BMS-214662 induced dephosphorylation of Crkl in remaining viable cells at 72 hours and 6 days, suggesting inhibition of Bcr-Abl kinase activity. In conclusion, BMS-214662 is highly effective against CML cells, including, for the first time, the primitive quiescent stem cell fraction, overcoming the accumulation of this population seen with IM or dasatinib in vitro.

BMS-214662 Eliminates CML Stem Cells and Is Active Against Blast Crisis CML and Cells Expressing BCR-ABL Kinase Mutations.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 739-739 ◽  
Author(s):  
Mhairi Copland ◽  
Linda Richmond ◽  
Ashley Hamilton ◽  
Elaine K. Allan ◽  
Junia V. Melo ◽  
...  
Keyword(s):  
Stem Cells ◽  
Caspase 3 ◽  
Blast Crisis ◽  
Chronic Phase ◽  
Drug Control ◽  
Ki 67 ◽  
Abl Kinase ◽  
Cell Counts ◽  
Significant Difference

Abstract Recently, we have shown that BMS-214662, a cytotoxic farnesyltransferase inhibitor (FTI), targets primitive progenitor cells (PPC) in chronic myeloid leukaemia (CML) [Copland et al, Blood2005;106:204a]. These PPC are believed to be responsible for the molecular persistence which occurs following treatment with imatinib mesylate (IM) in CML. We have also shown that neither dasatinib (BMS-354825) nor nilotinib (AMN107) targets these PPC in vitro [Copland et al, Blood2006;107:4532; Jorgensen et al, Blood2005;106:314a]. To further investigate the efficacy of BMS-214662 against CML stem cells we performed long term culture-initiating cell (LTC-IC) assays with both chronic phase CML and normal CD34+ progenitors to assess drug selectivity. The CD34+ cells were treated for 72 hours under the following conditions no drug control, IM 5μM, dasatinib 150nM, BMS-214662 250nM, IM + BMS-214662, dasatinib + BMS-214662 before LTC-IC assay. Compared to the no drug control, CD34+ CML cells showed increased colony formation in the IM and dasatinib arms (181 and 178% respectively) indicating that, by inhibiting proliferation, these drugs exert a protective effect on CML PPC. The addition of BMS-214662 to either IM or dasatinib significantly reduced the number of colonies compared to either agent alone (P=0.045 and P=0.029 respectively). The BMS-214662 containing arms showed a dramatic reduction in total colony numbers to < 2.5% of the no drug control (P=0.038). In 2/3 experiments, FISH showed that, after treatment with BMS-214662, the majority of cells from residual colonies were BCR-ABL negative. In addition, BMS-214662 was less toxic to normal LTC-IC from healthy donors. Using CFSE-based flow cytometry to track cell division, we assessed BMS-214662 alone and in combination with IM or dasatinib in blast crisis (BC) CML. BMS-214662 reduced the number of PPC compared to the no drug control and acted synergistically with IM or dasatinib to reduce the total number of viable cells and PPC in BC CML. To determine if the effects of BMS-214662 in CML were due to inhibition of Ras, we used the CFSE method, caspase-3 activity to measure apoptosis and Ki-67/7AAD cell cycle analysis to assess quiescence to compare BMS-214662 with another FTI with equivalent Ras inhibition, BMS-225975. As previously, after 6 days culture, not only had BMS-214662 significantly reduced the number of CML PPC compared to the no drug control (P=0.018), but also compared to BMS-225975 containing arms (P=0.024). There was no significant difference between the no drug control and BMS-225975 arms. Caspase-3 activity was highest in the BMS-214662-containing arms. After 72 hours, Ki-67/7AAD analysis showed reduced G0 cells in the BMS-214662 arms. The disparate effects of BMS-214662 and BMS-225975 suggest that the efficacy of BMS-214662 in CML is not via inhibition of Ras. We then determined the efficacy of BMS-214662 in Ba/F3 cells expressing different BCR-ABL kinase mutations (WT BCR-ABL, T315I, M351T and H396P) using viable cell counts and 3H thymidine proliferation assays. BMS-214662 was equipotent in both WT BCR-ABL and mutant BCR-ABL kinase expressing cells. These results provide further evidence that BMS-214662 selectively targets CML stem cells, acts in synergy with IM or dasatinib and may prove useful in the management of IM-resistant and BC CML.

Leukemic Stem Cells of Chronic Phase CML Patients Possess Uniquely Elevated BCR-ABL Kinase Activity and Acquire Spontaneous BCR-ABL Kinase Domain Mutations at a High Frequency.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 438-438 ◽  
Author(s):  
Xiaoyan Jiang ◽  
Kyi Min Saw ◽  
Allen Eaves ◽  
Connie Eaves
Keyword(s):  
Stem Cells ◽  
Tyrosine Kinase ◽  
Kinase Activity ◽  
Point Mutations ◽  
Chronic Phase ◽  
Kinase Domain ◽  
Tyrosine Kinase Activity ◽  
Abl Kinase ◽  
Kinase Domain Mutations

Abstract Growing evidence indicates that the therapeutic potential of imatinib mesylate (IM) for the treatment of CML may be limited initially by a relative innate resistance of the leukemic stem cells and eventually by an accumulation of cells with BCR-ABL tyrosine kinase domain mutations. We now show that the amount and tyrosine kinase activity of p210-BCR-ABL in the most primitive and relatively IM-unresponsive lin−CD34+CD38− CML cells is 3 to 10-fold higher than in the majority of the lin−CD34+CD38+ CML progenitors (n=3). These results confirm previous BCR-ABL transcript data and identify elevated p210-BCR-ABL expression to be a likely important factor in the characteristic IM-insensitivity of very primitive CML cells. To determine whether in vivo, CML stem cells also accumulate gene mutations affecting the BCR-ABL kinase domain, cDNAs were prepared from RNA extracts of purified lin−CD34+CD38− cells isolated from 3 chronic phase patients that had not received IM therapy. Bidirectional sequencing of individually cloned cDNAs from these samples revealed BCR-ABL kinase domain mutations in 2 of the 3 patients at frequencies of 10% (1/10), 20% (2*/10,*identical mutations). Incubation of these lin−CD34+CD38− cells in vitro for 2–3 wk ± a high concentration of IM (up to 10 μM, which was sufficient to reduce the tyrosine kinase activity in the input cells by 70±12% and in their 2 wk progeny by 10±5%) selected a subpopulation of more differentiated and completely IM-resistant cells. This was shown in Western blots by the inability of 10 μM IM to reduce either their p210-BCR-ABL tyrosine kinase activity or CrkL phosphorylation and in methylcellulose assays ±5 μM IM. As predicted, IM-selected cells showed a higher frequency of kinase domain mutations (13–20% vs 0–20% of cDNA clones analyzed from 3 wk cells cultured ±IM). Analysis of individual colonies produced from CFCs in the cultured cells showed all (21/21) colonies from IM-selected cells had mutations vs 50% (5/10) in those cultured without IM. The total frequency of mutant cDNAs detected was also increased in the IM-resistant cells (35–55% vs 10–25% mutant cDNAs in selected vs control cells). Interestingly, in most cases, both wild-type and mutant cDNAs were identified in the same colony, indicating de novo generation of mutations in vitro. Overall, >50 different mutations were identified. These included 10 point mutations previously associated with clinical IM resistance (including G250 and T315), another 13 point mutations previously identified in a comprehensive mutational screen, and >20 previously undescribed mutations. Several of the latter affect the critical region of the P loop, the c-helix and the activation loop and would be predicted to confer significant IM resistance. To investigate the possibility that the observed genomic instability of very primitive CML cells might be related to their elevated innate p210-BCR-ABL activity, BCR-ABL transcript levels in individual IM-selected, fully resistant and control (similarly treated but no IM exposure) colonies were compared. This showed that BCR-ABL transcripts were ~20-fold higher (P<0.05) in the resistant colonies (30 assessed from 3 patients). These findings suggest that the increased BCR-ABL expression and activity that uniquely characterizes the most primitive CML cells may contribute not only to their innate insensitivity to IM but also to a deregulation of genomic stability leading to the emergence of IM-resistant mutants and other subclones associated with disease progression.

Modeling CML Development and Drug Resistance Using iPSC Technology,

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3767-3767
Author(s):  
Kran Suknuntha ◽  
Yuki Ishii ◽  
Kejin Hu ◽  
Jean YJ Wang ◽  
Igor Slukvin
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Drug Resistance ◽  
Stem Cell ◽  
Blood Cells ◽  
Kinase Activity ◽  
Hematopoietic Cells ◽  
Patient Specific ◽  
Hematopoietic Progenitors ◽  
Abl Kinase

Abstract Abstract 3767 Reprogramming of neoplastic cells to pluripotency provides a unique tool to personalize the exploration of tumor pathogenic mechanisms and drug resistance using iPSCs with patient-specific chromosomal abnormalities. We have developed a technology to generate transgene-free iPSCs from bone marrow and cord blood cells employing episomal vectors. Using this approach we created transgene-free iPSCs from a patient with CML in the chronic phase. CMLiPSCs showed a unique complex chromosomal translocation identified in the patinet's marrow sample while displaying typical embryonic stem cell phenotype and pluripotent differentiation potential. Importantly, these CMLiPSCs are devoid of genomic integration and expression of reprogramming factors, which are incompatible for modeling tumor development and drug response (Hu et al. Blood 117:e109). We have also shown that these CMLiPSCs contain the BCR-ABL oncogene without any detectable mutations in its kinase domain. By coculture with OP9, we generated APLNR+ mesodermal cells, MSCs, and lin-CD34+CD45+ hematopoietic progenitors from CMLiPSCs, and control BMiPSCs from a normal subject and analyzed the levels of BCR-ABL protein and tyrosine-phosphorylated (pTyr) cellular proteins in the different cell populations. The highest level of BCR-ABL protein expression was found in the in undifferentiated iPSCs, however, the overall cellular pTyr levels was lower than the control BMiPSCs, suggesting that BCR-ABL kinase activity was suppressed in the CMLiPScs. Consistent with these findings, imatinib does not inhibit the growth and survival of these CMLiPSCs. The levels of BCR-ABL protein decreased upon differentiation with a major reduction observed when cells became mesoderm. Following differentiation of CMLiPSC-derived mesoderm into the MSCs and lin-CD34+CD45+ hematopoietic progenitors, the levels of BCR-ABL protein did not change significantly, indicating that the major epigenetic regulation of BCR-ABL expression occurs during the transition to mesoderm. In spite of the decrease in BCR-ABL expression, the total pTyr levels significantly increased following transition of CMLiPSCs to mesoderm and blood cells, suggesting recovery of BCR-ABL kinase activity during differentiation. Interestingly, we found that imatinib had no effect on CFC potential of the most primitive lin-CD34+CD45+ hematopoietic progenitors derived from CMLiPSCs, while significant inhibition in hematopoietic CFC potential was observed when we used the patient's bone marrow cells. Following expansion of lin-CD34+CD45+ progenitors in serum-free medium with cytokines, we found that more differentiated hematopoietic cells became imatinib sensitive. The differential response of progenitors versus more differentiated cells to imatinib recapitulate the clinical observation that CML stem cells display innate resistance to imatinib but their differentiated progenies become sensitive to this BCR-ABL kinase inhibitor. The iPSC-based models provide several advantages for the study of CML pathogenesis. iPSCs can provide an unlimited supply of hematopoietic cells carrying patient-specific genetic abnormalities. Using well-defined temporal windows and surface markers, distinct cell subsets with tumor-initiating/tumor-propagating potential after transplantation in immunodeficient mice could be identified and used for drug screening. iPSC models make it possible to address CML stem-cell potential at various stages of differentiation for which it may be difficult to obtain samples from the patient, for example, at the hemangioblast stage. They also provide a unique opportunity to explore the interplays between epigenetics and oncogene function, as we have demonstrated using the CMLiPSCs. The major unsolved question is why CML stem cells are naturally resistant to imatinib, and this question can be addressed using the iPS system. Disclosures: Slukvin: CDI: Consultancy, Equity Ownership.

Characterization of cancer stem cells in chronic myeloid leukaemia

2007 ◽  
Vol 35 (5) ◽  
pp. 1347-1351 ◽  
Author(s):  
H.G. Jørgensen ◽  
T.L. Holyoake
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Chronic Myeloid Leukaemia ◽  
Tyrosine Kinase ◽  
Myeloid Leukaemia ◽  
Cell Population ◽  
Single Agent ◽  
Stem Cell Population ◽  
Wild Type ◽  
Apoptosis Protein

CML (chronic myeloid leukaemia) is a myeloproliferative disease that originates in an HSC (haemopoietic stem cell) as a result of the t(9;22) translocation, giving rise to the Ph (Philadelphia chromosome) and bcr-abl oncoprotein. The disease starts in CP (chronic phase), but as a result of genomic instability, it progresses over time to accelerated phase and then to BC (blast crisis), becoming increasingly resistant to therapy. bcr-abl is a constitutively active tyrosine kinase that has been targeted by TKIs (tyrosine kinase inhibitors), including IM (imatinib mesylate), nilotinib and dasatinib. We have developed various flow cytometry techniques to enable us to isolate candidate CML stem cells from CP patients at diagnosis that efflux Hoechst dye, express CD34, lack CD38 and are cytokine-non-responsive in culture over periods of up to 12 days in growth factors. These stem cells have been shown to regenerate bcr-abl-positive haemopoiesis in immunocompromised mice upon transplantation. We previously demonstrated that IM was antiproliferative for CML stem cells but did not induce apoptosis. Clinical experience now confirms that IM may not target CML stem cells in vivo with few patients achieving complete molecular remission and relapse occurring rapidly upon drug withdrawal. Our recent efforts have focused on understanding why CML stem cells are resistant to IM and on trying to find novel ways to induce apoptosis of this population. We have shown that CML stem cells express very high levels of functional wild-type bcr-abl; no kinase domain mutations have been detected in the stem cell population. Dasatinib, a more potent multitargeted TKI than IM, inhibits bcr-abl activity more efficiently than IM but still does not induce apoptosis of the stem cell population. Most recently, we have tested a number of novel drug combinations and found that FTIs (farnesyl transferase inhibitors) have activity against CML. BMS-214662 is the most effective of these and induces apoptosis of phenotypically and functionally defined CML stem cells in vitro, as a single agent and in combination with IM or dasatinib. The effect against CML stem cells is selective with little effect on normal stem cells. The drug is also effective against BC CML stem cells and equally effective against wild-type and mutant bcr-abl, including the most resistant mutant T315I. In association with apoptosis, there is activation of caspase 8 and caspase 3, inhibition of the MAPK pathway, IAP-1 (inhibitor of apoptosis protein-1), NF-κB (nuclear factor κB) and iNOS (inducible nitric oxide synthase). Furthermore, BMS-214662 synergizes with MEK1/2 [MAPK (mitogen-activated protein kinase)/ERK (extracellular-signal-regulated kinase) kinase 1/2] inhibitors, suggesting a second mechanism other that RAS inhibition for induction of apoptosis. Our intentions are now to explore the activity of BMS-214662 in other cancer stem cell disorders and to move this preclinical work to a clinical trial combining dasatinib with BMS-214662 in CML.

Gene Expression Profiling in Quiescent Stem Cells from Normal and Chronic Myeloid Leukaemia Patients.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2962-2962
Author(s):  
Susan M. Graham ◽  
Gerry J. Graham ◽  
Tessa L. Holyoake
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Stem Cells ◽  
Stem Cell ◽  
Chronic Myeloid Leukaemia ◽  
Myeloid Leukaemia ◽  
Stem Cell Marker ◽  
Quiescent Cells ◽  
Dividing Cells ◽  
Quiescent Stem Cells

Abstract Earlier studies have shown that Ph+ quiescent cells exist in chronic myeloid leukaemia (CML) (Blood (1999)94:2056) and we have previously shown that these cells are primitive in that they express the stem cell marker CD34. We have also shown that quiescent CML stem cells are insensitive to the effects of imatinib (IM Novartis Pharma) (Blood (2002) 99:319) and may present a possible source for relapse. This quiescent population therefore represents a potentially significant clinical problem and thus studies aimed at developing methods for eradicating this population are timely. In an effort to identify molecular markers of this population that may allow it to be specifically targeted during therapy, we have set out to investigate the transcriptional differences between quiescent and cycling stem cells. To this end, we have used specific stem cell enrichment and sorting protocols. Leukapheresis products from CML patients (N=5) in chronic phase at diagnosis and mobilised peripheral blood from allogeneic donors (N=3), were selected for CD34+ cells. Hoechst 33342 and Pyronin Y were used to discriminate the quiescent (G0) cells identified as Hoechstlo/Pyroninlo from the cycling cells. In combination with propidium iodide for dead cell exclusion we were able to sort 4–9x105 viable, quiescent stem cells and 4–11x106 cycling cells, which were processed for microarrays. Affymetrix gene chips (U133A) were used for the analysis and the data obtained was analysed using GeneSpring. Number of Genes Changed in Each Comparison 3 Fold 4 Fold 5 Fold CML G0 V CML Div 37 21 10 Norm G0 V Norm Div 188 92 47 CML G0 V Norm G0 168 85 49 CML Div V Norm Div 49 27 8 Initial analysis indicates that the greatest differences in gene expression are between the normal quiescent cells (G0) and normal dividing cells (Div) and between the normal quiescent cells and CML quiescent cells. A large percentage of the genes differentially expressed between the quiescent and cycling normal cells encode regulators of the cell cycle confirming the success of the sorting strategy for quiescent and cycling cells A selection of Genes Up-Regulated in Normal Cycling Cells Compared to G0 Gene Fold Up-regulation PCNA 3 CDC2 8 CCNB2 5 CCN1 3.5 CDC20 6 CDC25A 3.5 MCM5 3 In addition, many of the genes identified in our analysis are consistent with other published expression profiles for haemopoietic cells. Curiously, we have identified unanticipated changes in expression of cell cycle genes in the CML quiescent cells, which merit further investigation. We have also identified a number of unexpected genes as being more than 5 fold changed in the quiescent cells compared to dividing cells for both normal and CML samples. Specifically, there is a large cohort of genes preferentially expressed in quiescent normal or CML cells, which encode members of the chemokine family of proteins. Work is ongoing to establish the relevance, if any, of these genes to stem cell quiescence.

Chronic myeloid leukaemia: stem cell derived but progenitor cell driven

2005 ◽  
Vol 109 (1) ◽  
pp. 13-25 ◽  
Author(s):  
Stephen B. MARLEY ◽  
Myrtle Y. GORDON
Keyword(s):  
Stem Cell ◽  
Chronic Myeloid Leukaemia ◽  
Myeloid Leukaemia ◽  
Cell Population ◽  
Progenitor Cell ◽  
Stem Cell Population ◽  
Self Renewal ◽  
Myeloid Progenitor ◽  
In Vitro Investigation

The biology of CML (chronic myeloid leukaemia) has been extensively investigated as the disease is a paradigm of neoplasms induced when a translocation results in expression of a novel fusion protein, in this instance p210BCR-ABL. Although CML manifests itself principally as unregulated expansion of the myeloid lineage, the lesion is present in the stem cell population and it has long been assumed that disregulated stem cell kinetics must underlie the basic pathology of the disease. In this review, we present evidence that, in normal haemopoiesis, less primitive precursor cells retain considerable flexibility in their capacity to undergo self-renewal, allowing them to maintain lineage-specific homoeostasis without inflicting proliferative stress upon the stem cell population. This mechanism is dysregulated in CML and we have developed a self-renewal assay for CFU-GM (colony-forming unit-granulocyte/macrophage) which demonstrates that, in CML, the PI (proliferative index) of the myeloid progenitor cell population is increased. The ability to measure the PI as an endpoint of p210BCR-ABL expression gives considerable versatility to the in vitro investigation of putative therapeutic regimes in CML.

scholarly journals Regulation of sarcomagenesis by the empty spiracles homeobox genes EMX1 and EMX2

2021 ◽  
Vol 12 (6) ◽  
Author(s):  
Manuel Pedro Jimenez-García ◽  
Antonio Lucena-Cacace ◽  
Daniel Otero-Albiol ◽  
Amancio Carnero
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Transcription Factors ◽  
Neural Crest ◽  
Tumor Suppressors ◽  
Homeobox Genes ◽  
Neuronal Cell ◽  
Cell Gene Expression

AbstractThe EMX (Empty Spiracles Homeobox) genes EMX1 and EMX2 are two homeodomain gene members of the EMX family of transcription factors involved in the regulation of various biological processes, such as cell proliferation, migration, and differentiation, during brain development and neural crest migration. They play a role in the specification of positional identity, the proliferation of neural stem cells, and the differentiation of certain neuronal cell phenotypes. In general, they act as transcription factors in early embryogenesis and neuroembryogenesis from metazoans to higher vertebrates. The EMX1 and EMX2’s potential as tumor suppressor genes has been suggested in some cancers. Our work showed that EMX1/EMX2 act as tumor suppressors in sarcomas by repressing the activity of stem cell regulatory genes (OCT4, SOX2, KLF4, MYC, NANOG, NES, and PROM1). EMX protein downregulation, therefore, induced the malignance and stemness of cells both in vitro and in vivo. In murine knockout (KO) models lacking Emx genes, 3MC-induced sarcomas were more aggressive and infiltrative, had a greater capacity for tumor self-renewal, and had higher stem cell gene expression and nestin expression than those in wild-type models. These results showing that EMX genes acted as stemness regulators were reproduced in different subtypes of sarcoma. Therefore, it is possible that the EMX genes could have a generalized behavior regulating proliferation of neural crest-derived progenitors. Together, these results indicate that the EMX1 and EMX2 genes negatively regulate these tumor-altering populations or cancer stem cells, acting as tumor suppressors in sarcoma.

scholarly journals Cell Source-Dependent In Vitro Chondrogenic Differentiation Potential of Mesenchymal Stem Cell Established from Bone Marrow and Synovial Fluid of Camelus dromedarius

Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1918
Author(s):  
Young-Bum Son ◽  
Yeon Ik Jeong ◽  
Yeon Woo Jeong ◽  
Mohammad Shamim Hossein ◽  
Per Olof Olsson ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Stem Cell ◽  
Synovial Fluid ◽  
Cartilage Regeneration ◽  
Cartilage Tissue ◽  
Chondrocyte Differentiation ◽  
Differentiation Potential ◽  
Proliferation Capacity

Mesenchymal stem cells (MSCs) are promising multipotent cells with applications for cartilage tissue regeneration in stem cell-based therapies. In cartilage regeneration, both bone marrow (BM-MSCs) and synovial fluid (SF-MSCs) are valuable sources. However, the cellular characteristics and chondrocyte differentiation potential were not reported in either of the camel stem cells. The in vitro chondrocyte differentiation competence of MSCs, from (BM and SF) sources of the same Camelus dromedaries (camel) donor, was determined. Both MSCs were evaluated on pluripotent markers and proliferation capacity. After passage three, both MSCs showed fibroblast-like morphology. The proliferation capacity was significantly increased in SF-MSCs compared to BM-MSCs. Furthermore, SF-MSCs showed an enhanced expression of transcription factors than BM-MSCs. SF-MSCs exhibited lower differentiation potential toward adipocytes than BM-MSCs. However, the osteoblast differentiation potential was similar in MSCs from both sources. Chondrogenic pellets obtained from SF-MSCs revealed higher levels of chondrocyte-specific markers than those from BM-MSCs. Additionally, glycosaminoglycan (GAG) content was elevated in SF-MSCs related to BM-MSCs. This is, to our knowledge, the first study to establish BM-MSCs and SF-MSCs from the same donor and to demonstrate in vitro differentiation potential into chondrocytes in camels.

scholarly journals “Empowering” Cardiac Cells via Stem Cell Derived Mitochondrial Transplantation- Does Age Matter?

2021 ◽  
Vol 22 (4) ◽  
pp. 1824
Author(s):  
Matthias Mietsch ◽  
Rabea Hinkel
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Treatment Strategies ◽  
Cardiac Cells ◽  
Aging Effects ◽  
Beneficial Effects ◽  
Micro Rnas ◽  
New Treatment

With cardiovascular diseases affecting millions of patients, new treatment strategies are urgently needed. The use of stem cell based approaches has been investigated during the last decades and promising effects have been achieved. However, the beneficial effect of stem cells has been found to being partly due to paracrine functions by alterations of their microenvironment and so an interesting field of research, the “stem- less” approaches has emerged over the last years using or altering the microenvironment, for example, via deletion of senescent cells, application of micro RNAs or by modifying the cellular energy metabolism via targeting mitochondria. Using autologous muscle-derived mitochondria for transplantations into the affected tissues has resulted in promising reports of improvements of cardiac functions in vitro and in vivo. However, since the targeted treatment group represents mainly elderly or otherwise sick patients, it is unclear whether and to what extent autologous mitochondria would exert their beneficial effects in these cases. Stem cells might represent better sources for mitochondria and could enhance the effect of mitochondrial transplantations. Therefore in this review we aim to provide an overview on aging effects of stem cells and mitochondria which might be important for mitochondrial transplantation and to give an overview on the current state in this field together with considerations worthwhile for further investigations.

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