scholarly journals Cryptic developmental events determine medulloblastoma radiosensitivity and cellular heterogeneity without altering transcriptomic profile

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Daniel Shiloh Malawsky ◽  
Seth J. Weir ◽  
Jennifer Karin Ocasio ◽  
Benjamin Babcock ◽  
Taylor Dismuke ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Tumor Microenvironment ◽  
Transgenic Mice ◽  
Genetically Engineered ◽  
Neural Progenitors ◽  
Cellular Heterogeneity ◽  
Neuronal Stem Cells ◽  
Precise Understanding ◽  
Genetically Engineered Mice

AbstractIt is unclear why medulloblastoma patients receiving similar treatments experience different outcomes. Transcriptomic profiling identified subgroups with different prognoses, but in each subgroup, individuals remain at risk of incurable recurrence. To investigate why similar-appearing tumors produce variable outcomes, we analyzed medulloblastomas triggered in transgenic mice by a common driver mutation expressed at different points in brain development. We genetically engineered mice to express oncogenic SmoM2, starting in multipotent glio-neuronal stem cells, or committed neural progenitors. Both groups developed medulloblastomas with similar transcriptomic profiles. We compared medulloblastoma progression, radiosensitivity, and cellular heterogeneity, determined by single-cell transcriptomic analysis (scRNA-seq). Stem cell-triggered medulloblastomas progressed faster, contained more OLIG2-expressing stem-like cells, and consistently showed radioresistance. In contrast, progenitor-triggered MBs progressed slower, down-regulated stem-like cells and were curable with radiation. Progenitor-triggered medulloblastomas also contained more diverse stromal populations, with more Ccr2+ macrophages and fewer Igf1+ microglia, indicating that developmental events affected the subsequent tumor microenvironment. Reduced mTORC1 activity in M-Smo tumors suggests that differential Igf1 contributed to differences in phenotype. Developmental events in tumorigenesis that were obscure in transcriptomic profiles thus remained cryptic determinants of tumor composition and outcome. Precise understanding of medulloblastoma pathogenesis and prognosis requires supplementing transcriptomic/methylomic studies with analyses that resolve cellular heterogeneity.

scholarly journals Cryptic developmental events determine medulloblastoma radiosensitivity and cellular heterogeneity without altering transcriptomic profile.

2020 ◽  
Author(s):  
Daniel Shiloh Malawsky ◽  
Seth Weir ◽  
Jennifer Ocasio ◽  
Ben Babcock ◽  
Taylor Dismuke ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Genetically Engineered ◽  
Response To Therapy ◽  
Cellular Heterogeneity ◽  
Cerebellar Granule Neuron ◽  
Transcriptomic Profile ◽  
Precise Understanding ◽  
Genetically Engineered Mice ◽  
Long Term Survivors

Abstract Patients with medulloblastoma are typically treated with a narrow range of therapies, but may experience widely divergent outcomes; 80-90% become long-term survivors while 20% develop incurable recurrence. Transcriptomic profiling has identified four subgroups with different recurrence risks, but outcomes remain variable for individual patients within each subgroup. To gain new insight into why patients with similar-appearing tumors have variable outcomes, we examined how the timing of tumor initiation effects medulloblastomas triggered by a single, common driver mutation. We genetically-engineered mice to express an oncogenic Smo allele starting early in development in the broad lineage of neural stem cells, or later, in the more committed lineage of cerebellar granule neuron progenitors. Both groups developed medulloblastomas and no other tumors. We compared medulloblastoma progression, response to therapy, gene expression profile and cellular heterogeneity, determined by single cell transcriptomic analysis (scRNA-seq). The average transcriptomic profiles of the tumors were similar. However, stem cell-triggered medulloblastomas progressed faster, contained more OLIG2-expressing tumor stem cells, and consistently showed radioresistance. In contrast, progenitor-triggered MBs progressed slower, lost stem cell character over time and were radiosensitive. Progenitor-triggered medulloblastomas also contained more diverse stromal populations, including tumor-associated macrophages, indicating that the timing of oncogenesis affected the subsequent interactions between the tumor and microenvironment. Our findings show that developmental events in tumorigenesis may be impossible to infer from transcriptomic profile, but while remaining cryptic can nevertheless influence tumor composition and the outcome of therapy. Precise understanding of medulloblastoma pathogenesis and prognosis requires supplementing transcriptomic data with biomarkers of cellular heterogeneity.

scholarly journals The CXCL12 Crossroads in Cancer Stem Cells and Their Niche

Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 469
Author(s):  
Juan Carlos López-Gil ◽  
Laura Martin-Hijano ◽  
Patrick C. Hermann ◽  
Bruno Sainz
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Tumor Microenvironment ◽  
Cancer Stem Cells ◽  
Crucial Role ◽  
Diverse Group ◽  
Hematopoietic Stem ◽  
Stem Cell Support ◽  
Cell Support ◽  
Tumor Entities

Cancer stem cells (CSCs) are defined as a subpopulation of “stem”-like cells within the tumor with unique characteristics that allow them to maintain tumor growth, escape standard anti-tumor therapies and drive subsequent repopulation of the tumor. This is the result of their intrinsic “stem”-like features and the strong driving influence of the CSC niche, a subcompartment within the tumor microenvironment that includes a diverse group of cells focused on maintaining and supporting the CSC. CXCL12 is a chemokine that plays a crucial role in hematopoietic stem cell support and has been extensively reported to be involved in several cancer-related processes. In this review, we will provide the latest evidence about the interactions between CSC niche-derived CXCL12 and its receptors—CXCR4 and CXCR7—present on CSC populations across different tumor entities. The interactions facilitated by CXCL12/CXCR4/CXCR7 axes seem to be strongly linked to CSC “stem”-like features, tumor progression, and metastasis promotion. Altogether, this suggests a role for CXCL12 and its receptors in the maintenance of CSCs and the components of their niche. Moreover, we will also provide an update of the therapeutic options being currently tested to disrupt the CXCL12 axes in order to target, directly or indirectly, the CSC subpopulation.

scholarly journals DYRK1A Negatively Regulates CDK5-SOX2 Pathway and Self-Renewal of Glioblastoma Stem Cells

2021 ◽  
Vol 22 (8) ◽  
pp. 4011
Author(s):  
Brianna Chen ◽  
Dylan McCuaig-Walton ◽  
Sean Tan ◽  
Andrew P. Montgomery ◽  
Bryan W. Day ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cell Differentiation ◽  
Critical Role ◽  
Stem Cell Differentiation ◽  
Neural Progenitor Cell ◽  
Cellular Heterogeneity ◽  
Differentiation Potential ◽  
Glioblastoma Stem Cells ◽  
Glioblastoma Stem Cell

Glioblastoma display vast cellular heterogeneity, with glioblastoma stem cells (GSCs) at the apex. The critical role of GSCs in tumour growth and resistance to therapy highlights the need to delineate mechanisms that control stemness and differentiation potential of GSC. Dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) regulates neural progenitor cell differentiation, but its role in cancer stem cell differentiation is largely unknown. Herein, we demonstrate that DYRK1A kinase is crucial for the differentiation commitment of glioblastoma stem cells. DYRK1A inhibition insulates the self-renewing population of GSCs from potent differentiation-inducing signals. Mechanistically, we show that DYRK1A promotes differentiation and limits stemness acquisition via deactivation of CDK5, an unconventional kinase recently described as an oncogene. DYRK1A-dependent inactivation of CDK5 results in decreased expression of the stemness gene SOX2 and promotes the commitment of GSC to differentiate. Our investigations of the novel DYRK1A-CDK5-SOX2 pathway provide further insights into the mechanisms underlying glioblastoma stem cell maintenance.

205 SELECTIVE ANTITUMOR THERAPEUTIC EFFECT OF 5-FLUOROCYTOSINE AND INTERFERON-BETA AGAINST BREAST AND ENDOMETRIAL CANCER CELLS BY ENGINEERED STEM CELLS EXPRESSING CYTOSINE DEAMINASE AND HUMAN INTERFERON-BETA

2012 ◽  
Vol 24 (1) ◽  
pp. 215
Author(s):  
B.-R. Yi ◽  
K.-A. Hwang ◽  
K.-C. Choi
Keyword(s):  
Stem Cells ◽  
Endometrial Cancer ◽  
Stem Cell ◽  
Cell Viability ◽  
Cancer Cells ◽  
Therapeutic Efficacy ◽  
Interferon Beta ◽  
Cytosine Deaminase ◽  
Genetically Engineered ◽  
Human Interferon

When genetically engineered with chemo- or immunotherapeutic genes, stem cells can exhibit a potent therapeutic efficacy combined with their strong tumour tropism. The stem cells were genetically engineered to express a bacterial cytosine deaminase (CD) gene and/or a human interferon-β (IFN-b) gene; thus, 2 stem cell lines, HB1.F3.CD and HB1.F3.CD.IFN-b, were generated, respectively. The CD gene, one of suicide gene, can convert the nontoxic prodrug 5-fluorocytosine (5-FC) to an active form, 5-fluorouracil (5-FU), which has a powerful cytotoxic effect on cancer cells. In addition, human IFN-b is a typical cytokine having an antitumour effect. Using reverse transcription-PCR (RT-PCR), we confirmed CD and/or IFN-b gene expression in HB1.F3 (maternal stem cells) and HB1.F3.CD and HB1.F3.CD.IFN-b cells and the expression of chemoattractant ligands and receptors including stem cell factor (SCF), CXCR4, c-kit, vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) in breast (MCF-7) and endometrial cancer (Ishikawa) cells. To determine the migratory capability of engineered stem cells, we performed a modified trans-well assay. In addition, to identify their therapeutic efficacy, we co-cultured HB1.F3.CD or HB1.F3.CD.IFN-b with breast and endometrial cancer cells and cell viability was measured by MTT assay. The engineered stem cells expressed CD and IFN-b genes and several chemoattractant molecules, SCF, CXCR4, VEGF/VEGFR2 and c-kit, were strongly expressed in breast and endometrial cancer cells. These stem cells were effectively migrated to breast and endometrial cancer cells due to chemoattractant molecules secreted by breast and endometrial cancer cells. In therapeutic efficacy, the viability of breast and endometrial cancer cells treated with 5-FC was reduced in the presence of the HB1.F3.CD and HB1.F3.CD.IFN-b cells. Cell viability was more reduced when co-cultured with HB1.F3.CD.IFN-b compared with HB1.F3.CD cells. In conclusion, the results from the present study suggest that genetically modified stem cells expressing CD and IFN-b can be used as a gene-based therapy for treating breast and endometrial cancer via their tumour tropism. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2011-0005723).

scholarly journals Metabolic Alterations in Pancreatic Cancer Progression

Cancers ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 2 ◽  
Author(s):  
Enza Vernucci ◽  
Jaime Abrego ◽  
Venugopal Gunda ◽  
Surendra K. Shukla ◽  
Aneesha Dasgupta ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Tumor Microenvironment ◽  
Cancer Cells ◽  
Cancer Progression ◽  
Precancerous Lesions ◽  
Genetically Engineered ◽  
Metabolic Reprogramming ◽  
Pancreatic Tumors ◽  
Metabolic Alterations ◽  
Genetically Engineered Mice

Pancreatic cancer is the third leading cause of cancer-related deaths in the USA. Pancreatic tumors are characterized by enhanced glycolytic metabolism promoted by a hypoxic tumor microenvironment and a resultant acidic milieu. The metabolic reprogramming allows cancer cells to survive hostile microenvironments. Through the analysis of the principal metabolic pathways, we identified the specific metabolites that are altered during pancreatic cancer progression in the spontaneous progression (KPC) mouse model. Genetically engineered mice exhibited metabolic alterations during PanINs formation, even before the tumor development. To account for other cells in the tumor microenvironment and to focus on metabolic adaptations concerning tumorigenic cells only, we compared the metabolic profile of KPC and orthotopic tumors with those obtained from KPC-tumor derived cell lines. We observed significant upregulation of glycolysis and the pentose phosphate pathway metabolites even at the early stages of pathogenesis. Other biosynthetic pathways also demonstrated a few common perturbations. While some of the metabolic changes in tumor cells are not detectable in orthotopic and spontaneous tumors, a significant number of tumor cell-intrinsic metabolic alterations are readily detectable in the animal models. Overall, we identified that metabolic alterations in precancerous lesions are maintained during cancer development and are largely mirrored by cancer cells in culture conditions.

scholarly journals Epsins Regulate Mouse Embryonic Stem Cell Exit from Pluripotency and Neural Commitment by Controlling Notch Activation

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Marina Cardano ◽  
Jacopo Zasso ◽  
Luca Ruggiero ◽  
Giuseppina Di Giacomo ◽  
Matteo Marcatili ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Embryonic Stem Cells ◽  
Notch Signaling ◽  
Neural Differentiation ◽  
Radial Glia ◽  
Embryonic Stem ◽  
Mouse Embryonic Stem Cell ◽  
Neural Progenitors ◽  
Notch Activation

Epsins are part of the internalization machinery pivotal to control clathrin-mediated endocytosis. Here, we report that epsin family members are expressed in mouse embryonic stem cells (mESCs) and that epsin1/2 knockdown alters both mESC exits from pluripotency and their differentiation. Furthermore, we show that epsin1/2 knockdown compromises the correct polarization and division of mESC-derived neural progenitors and their conversion into expandable radial glia-like neural stem cells. Finally, we provide evidence that Notch signaling is impaired following epsin1/2 knockdown and that experimental restoration of Notch signaling rescues the epsin-mediated phenotypes. We conclude that epsins contribute to control mESC exit from pluripotency and allow their neural differentiation by appropriate modulation of Notch signaling.

scholarly journals Extracellular Vesicles: Evolving Factors in Stem Cell Biology

2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Muhammad Nawaz ◽  
Farah Fatima ◽  
Krishna C. Vallabhaneni ◽  
Patrice Penfornis ◽  
Hadi Valadi ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Tumor Microenvironment ◽  
Extracellular Vesicles ◽  
Cell Biology ◽  
Trophic Factors ◽  
Stem Cell Biology ◽  
Cell Fates ◽  
Bidirectional Communication

Stem cells are proposed to continuously secrete trophic factors that potentially serve as mediators of autocrine and paracrine activities, associated with reprogramming of the tumor microenvironment, tissue regeneration, and repair. Hitherto, significant efforts have been made to understand the level of underlying paracrine activities influenced by stem cell secreted trophic factors, as little is known about these interactions. Recent findings, however, elucidate this role by reporting the effects of stem cell derived extracellular vesicles (EVs) that mimic the phenotypes of the cells from which they originate. Exchange of genetic information utilizing persistent bidirectional communication mediated by stem cell-EVs could regulate stemness, self-renewal, and differentiation in stem cells and their subpopulations. This review therefore discusses stem cell-EVs as evolving communication factors in stem cell biology, focusing on how they regulate cell fates by inducing persistent and prolonged genetic reprogramming of resident cells in a paracrine fashion. In addition, we address the role of stem cell-secreted vesicles in shaping the tumor microenvironment and immunomodulation and in their ability to stimulate endogenous repair processes during tissue damage. Collectively, these functions ensure an enormous potential for future therapies.

scholarly journals Adhesion Molecules Involved in Stem Cell Niche Retention During Normal Haematopoiesis and in Acute Myeloid Leukaemia

2021 ◽  
Vol 12 ◽  
Author(s):  
Julien M. P. Grenier ◽  
Céline Testut ◽  
Cyril Fauriat ◽  
Stéphane J. C. Mancini ◽  
Michel Aurrand-Lions
Keyword(s):  
Stem Cells ◽  
Drug Resistance ◽  
Stem Cell ◽  
Acute Myeloid Leukaemia ◽  
Myeloid Leukaemia ◽  
Adhesion Molecules ◽  
Molecular Mechanisms ◽  
Genetically Engineered ◽  
Cell Niche ◽  
Acute Myeloid

In the bone marrow (BM) of adult mammals, haematopoietic stem cells (HSCs) are retained in micro-anatomical structures by adhesion molecules that regulate HSC quiescence, proliferation and commitment. During decades, researchers have used engraftment to study the function of adhesion molecules in HSC’s homeostasis regulation. Since the 90’s, progress in genetically engineered mouse models has allowed a better understanding of adhesion molecules involved in HSCs regulation by BM niches and raised questions about the role of adhesion mechanisms in conferring drug resistance to cancer cells nested in the BM. This has been especially studied in acute myeloid leukaemia (AML) which was the first disease in which the concept of cancer stem cell (CSC) or leukemic stem cells (LSCs) was demonstrated. In AML, it has been proposed that LSCs propagate the disease and are able to replenish the leukemic bulk after complete remission suggesting that LSC may be endowed with drug resistance properties. However, whether such properties are due to extrinsic or intrinsic molecular mechanisms, fully or partially supported by molecular crosstalk between LSCs and surrounding BM micro-environment is still matter of debate. In this review, we focus on adhesion molecules that have been involved in HSCs or LSCs anchoring to BM niches and discuss if inhibition of such mechanism may represent new therapeutic avenues to eradicate LSCs.

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