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1.
Gynecol Oncol ; 191: 100-105, 2024 Oct 08.
Article in English | MEDLINE | ID: mdl-39383630

ABSTRACT

OBJECTIVE: Age-adjusted rates of new cervical cancer diagnoses in the United States have remained stable despite increasing availability of Human Papilloma Virus (HPV) vaccination. As it is well established that sociodemographic factors drive cervical cancer care inequity, we aimed to evaluate their impact on catch-up HPV vaccination rates in adults. METHODS: The All of Us (AoU) Research Program is a longitudinal cohort study sponsored by the National Institutes of Health. All participants ages 18-47 assigned female sex at birth enrolled between May 2018 and April 2023 were included in this analysis. Primary outcome was receipt of HPV vaccination. Bivariable and multivariable tests were used to examine associations. RESULTS: A total of 113,344 participants were identified in the AoU program, with 53 % (n = 60,594) self-identifying as a racial or ethnic minority. Only 3575 participants (3.2 %) were documented as having received HPV vaccination. Median age of vaccination was 26 and participants ages 18-27 were more likely to be vaccinated. Participants without health insurance (OR = 0.32, 95 % CI 0.26-0.40), stable employment (OR = 0.85, 95 % CI 0.79-0.91), and those who reported lower income (OR = 0.87, 95 % CI 0.79-0.97) were significantly less likely to have received HPV vaccination. Participants who described cost as a barrier to healthcare were also less likely to have received HPV vaccination (OR = 0.82, 95 % CI 0.73-0.93). CONCLUSION: Sociodemographic factors including low income, lack of health insurance, and lack of stable employment were all associated with lower likelihood of catch-up HPV vaccination among adult women living in the United States.

2.
bioRxiv ; 2024 Aug 19.
Article in English | MEDLINE | ID: mdl-39229096

ABSTRACT

Somatic mutations arising in hematopoietic stem cells (HSCs) may provide the latter with a fitness advantage, allowing the mutant HSC to clonally expand. Such mutations have been recurrently identified in the chromatin modifier, SRCAP, in both non-malignant and leukemic clones, suggesting that this gene plays a significant role in hematopoiesis. We generated a conditional Srcap loss of function murine model and determined the consequences of hematopoietic-specific loss of this gene. We show that Srcap is essential for normal fetal liver erythropoiesis and monocytopoiesis. In Srcap deficient fetal livers, the number of phenotypic HSCs is similar to that of controls, but these HSCs exhibit a profound repopulating defect. Likewise, conditional deletion of Srcap during adult hematopoiesis results in a rapid loss of HSCs. Loss of Srcap is associated with evidence of increased DNA damage in HSCs and lineage-restricted progenitors as assessed by y-H2AX expression. Consistent with this finding, we observed strong transcriptional upregulation of the p53 pathway in Srcap deficient erythroid precursors. Collectively our data highlight the importance of Srcap in maintaining HSC function and supporting hematopoietic differentiation and suggests that it plays an essential role in maintaining genomic integrity.

3.
Gynecol Oncol ; 190: 272-282, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39265465

ABSTRACT

OBJECTIVE: To assess the influence of geographies and race on the survival outcomes in patients diagnosed with cervical squamous cell carcinoma (CSCC) across three continents. METHODS: This multicontinental retrospective study was conducted in 8 hospitals across Asia, Europe, and North America (NA). Clinicopathologic data of 595 patients with presumed early stages of CSCC, treated surgically, with curative intent was collected. Descriptive analysis and Cox regression models were produced. RESULTS: A total of 595 patients, consisting of 445 (74.8 %) white, 75 (12.6 %) Blacks, and 75 (12.6 %) Asian patients were included. Geographical distribution comprised 69 % of patients from NA, 22 % from Europe, and 9 % from Asia. The median age at diagnosis was 46 years. The median overall survival (OS) and relapse-free survival (RFS) were 22.09 years and 21.19 years, respectively. Patient characteristics varied significantly across geographical regions, except for consensus tumor grade. Patients in Europe from middle-income countries with limited CC screening had a substantially higher risk of death than those in NA (HR, 1.79; 95 % CI, 1.13 to 2.79; p = 0.015). Patients from single center in Japan had higher risk of relapse than those from the four heterogeneous NA centers (sub-distribution hazard ratio, 2.19; 95 % CI, 1.22 to 3.95; p = 0.009), although OS did not differ significantly. Race remained statistically insignificant for survival outcomes across the three continents but seemed to influence survival outcomes in NA centers. CONCLUSION: Our study highlights impact of geographies and races on CSCC survival outcomes, emphasizing the need of considering these factors when developing targeted interventions against CSCC.

4.
Front Oncol ; 14: 1432333, 2024.
Article in English | MEDLINE | ID: mdl-39104719

ABSTRACT

Introduction: Ovarian and other peritoneal cancers have a strong tendency to metastasize into the surrounding adipose tissue. This study describes an effect of the adipose microenvironment on upregulation of sialic acid-containing glycans in ovarian cancer (OC). Heterogeneous populations of glycosylated OC tumors converged to a highly sialylated cell state that regulates tumorigenesis in an immune-dependent manner. Methods: We modeled the adipose microenvironment by conditioning growth media with human patient-derived adipose tissue. OC cell lines grown in the presence vs. absence of adipose conditioned media (ACM) were characterized by transcriptomics, western blotting, and chemical biology glycan labeling methods. Fluorescence-activated cell sorting was used to separate adipose-driven upregulation of hypersialylated ("SNA-high") vs. hyposialylated ("SNA-low") OC subpopulations. The two subpopulations were characterized by further transcriptomic and quantitative polymerase chain reaction analyses, then injected into a syngeneic mouse model. Immune system involvement was implicated using wild type and athymic nude mice with a primary endpoint of overall survival. Results: Adipose conditioning resulted in upregulation of sialyltransferases ST3GAL1, ST6GAL1, ST6GALNAC3, and ST8Sia1. In culture, OC cells displayed two distinct sialylated subpopulations that were stable for up to 9 passages, suggesting inherent heterogeneity in sialylation that is maintained throughout cell division and media changes. OC tumors that implanted in the omental adipose tissue exclusively reprogrammed to the highly sialylated subpopulation. In wild type C57BL/6 mice, only the hypersialylated SNA-high subpopulation implanted in the adipose, whereas the hyposialylated SNA-low subpopulation failed to be tumorigenic (p=0.023, n=5). In the single case where SNA-low established a tumor, post-mortem analysis revealed reprogramming of the tumor to the SNA-high state in vivo. In athymic nude mice, both subpopulations rapidly formed tumors, implicating a role of the adaptive immune system. Conclusions: These findings suggest a model of glycan-dependent tumor evolution wherein the adipose microenvironment reprograms OC to a tumorigenic state that resists the adaptive immune system. Mechanistically, adipose factors upregulate sialyltransferases. To our knowledge, this is the first demonstration of the effect of adipose microenvironment on OC tumor sialylation. Our results set the stage for translational applications targeting sialic acid pathways in OC and other peritoneal cancer tumorigenesis and metastasis.

5.
bioRxiv ; 2024 May 15.
Article in English | MEDLINE | ID: mdl-38798490

ABSTRACT

Sialylation, the addition of negatively charged sialic acid sugars to terminal ends of glycans, is upregulated in most cancers. Hypersialylation supports multiple pro-tumor mechanisms such as enhanced migration and invasion, resistance to apoptosis and immune evasion. A current gap in knowledge is the lack of understanding on how the tumor microenvironment regulates cancer cell sialylation. The adipose niche is a main component of most peritoneal cancers' microenvironment. This includes ovarian cancer (OC), which causes most deaths from all gynecologic cancers. In this report, we demonstrate that the adipose microenvironment is a critical regulator of OC cell sialylation. In vitro adipose conditioning led to an increase in both ⍺2,3- and ⍺2,6-linked cell surface sialic acids in both human and mouse models of OC. Adipose-induced sialylation reprogramming was also observed in vivo from intra-peritoneal OC tumors seeded in the adipose-rich omentum. Mechanistically, we observed upregulation of at least three sialyltransferases, ST3GAL1, ST6GAL1 and ST3GALNAC3. Hypersialylated OC cells consistently formed intra-peritoneal tumors in both immune-competent mice and immune-compromised athymic nude mice. In contrast, hyposiaylated OC cells persistently formed tumors only in athymic nude mice demonstrating that sialylation impacts OC tumor formation in an immune dependent manner. To our knowledge, this is the first demonstration of the effect of adipose microenvironment on OC tumor sialylation. Our results set the stage for translational applications targeting sialic acid pathways in OC and other peritoneal cancers.

6.
J Vis Exp ; (203)2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38345216

ABSTRACT

Ovarian cancer is the deadliest gynecologic malignancy. The omentum plays a key role in providing a supportive microenvironment to metastatic ovarian cancer cells as well as immune modulatory signals that allow tumor tolerance. However, we have limited models that closely mimic the interaction between ovarian cancer cells and adipose-rich tissues. To further understand the cellular and molecular mechanisms by which the omentum provides a pro-tumoral microenvironment, we developed a unique 3D ex vivo model of cancer cell-omentum interaction. Using human omentum, we are able to grow ovarian cancer cells within this adipose-rich microenvironment and monitor the factors responsible for tumor growth and immune regulation. In addition to providing a platform for the study of this adipose-rich tumor microenvironment, the model provides an excellent platform for the development and evaluation of novel therapeutic approaches to target metastatic cancer cells in this niche. The proposed model is easy to generate, inexpensive, and applicable to translational investigations.


Subject(s)
Ovarian Neoplasms , Peritoneal Neoplasms , Humans , Female , Peritoneal Neoplasms/secondary , Omentum , Ovarian Neoplasms/pathology , Adipose Tissue/pathology , Neoplasm Metastasis/pathology , Tumor Microenvironment
8.
J Ovarian Res ; 16(1): 233, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-38037081

ABSTRACT

BACKGROUND: Chromobox protein homolog 7 (CBX7), a member of the Polycomb repressor complex, is a potent epigenetic regulator and gene silencer. Our group has previously reported that CBX7 functions as a tumor suppressor in ovarian cancer cells and its loss accelerated formation of carcinomatosis and drove tumor progression in an ovarian cancer mouse model. The goal of this study is to identify specific signaling pathways in the ovarian tumor microenvironment that down-regulate CBX7. Given that adipocytes are an integral component of the peritoneal cavity and the ovarian tumor microenvironment, we hypothesize that the adipose microenvironment is an important regulator of CBX7 expression. RESULTS: Using conditioned media from human omental explants, we found that adipose-derived exosomes mediate CBX7 downregulation and enhance migratory potential of human ovarian cancer cells. Further, we identified adipose-derived exosomal miR-421 as a novel regulator of CBX7 expression and the main effector that downregulates CBX7. CONCLUSION: In this study, we identified miR-421 as a specific signaling pathway in the ovarian tumor microenvironment that can downregulate CBX7 to induce epigenetic change in OC cells, which can drive disease progression. These findings suggest that targeting exosomal miR-421 may curtail ovarian cancer progression.


Subject(s)
MicroRNAs , Ovarian Neoplasms , Animals , Mice , Humans , Female , Polycomb Repressive Complex 1/genetics , Ovarian Neoplasms/pathology , Signal Transduction , Cell Line, Tumor , MicroRNAs/genetics , MicroRNAs/metabolism , Gene Expression Regulation, Neoplastic , Tumor Microenvironment/genetics
9.
bioRxiv ; 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37986971

ABSTRACT

Background: Chromobox protein homolog 7 (CBX7), a member of the Polycomb repressor complex, is a potent epigenetic regulator and gene silencer. Our group has previously reported that CBX7 functions as a tumor suppressor in ovarian cancer cells and its loss accelerated formation of carcinomatosis and drove tumor progression in an ovarian cancer mouse model. The goal of this study is to identify specific signaling pathways in the ovarian tumor microenvironment that down-regulate CBX7. Given that adipocytes are an integral component of the peritoneal cavity and the ovarian tumor microenvironment, we hypothesize that the adipose microenvironment is an important regulator of CBX7 expression. Results: Using conditioned media from human omental explants, we found that adipose-derived exosomes mediate CBX7 downregulation and enhance migratory potential of human ovarian cancer cells. Further, we identified adipose-derived exosomal miR-421 as a novel regulator of CBX7 expression and the main effector that downregulates CBX7. Conclusion: In this study, we identified miR-421 as a specific signaling pathway in the ovarian tumor microenvironment that can downregulate CBX7 to induce epigenetic change in OC cells, which can drive disease progression. These findings suggest that targeting exosomal miR-421 may curtail ovarian cancer progression.

10.
Semin Respir Crit Care Med ; 44(4): 447-453, 2023 08.
Article in English | MEDLINE | ID: mdl-37308114

ABSTRACT

Malignant pleural effusions (MPE) have historically been associated with a poor prognosis, and patients often require a series of invasive procedures and hospitalizations that significantly reduce quality of life at the terminus of life. However, advances in the management of MPE have coincided with the era of immunotherapies, and to a lesser extent, antiangiogenic therapies for the treatment of lung cancer. Landmark studies have shown these drugs to improve overall survival and progression-free survival in patients with lung cancer, but a paucity of phase III trial data exists for the impact of immune checkpoint inhibitors (ICI) on lung cancers associated with MPE. This review will focus on the leading studies investigating the impact of ICI and antiangiogenic therapies in patients with lung cancer and MPE. The diagnostic and prognostic values of vascular endothelial growth factor and endostatin expression levels in malignancy will also be discussed. These advancements are changing the paradigm of MPE management from palliation to treatment for the first time since 1767 when MPE was first reported. The future holds the promise of durable response and extended survival in patients with MPE.


Subject(s)
Lung Neoplasms , Pleural Effusion, Malignant , Humans , Pleural Effusion, Malignant/drug therapy , Pleural Effusion, Malignant/diagnosis , Vascular Endothelial Growth Factor A , Quality of Life , Lung Neoplasms/drug therapy , Immunotherapy
11.
PLoS Genet ; 19(3): e1010319, 2023 03.
Article in English | MEDLINE | ID: mdl-36976799

ABSTRACT

One of the most common cell shape changes driving morphogenesis in diverse animals is the constriction of the apical cell surface. Apical constriction depends on contraction of an actomyosin network in the apical cell cortex, but such actomyosin networks have been shown to undergo continual, conveyor belt-like contractions before the shrinking of an apical surface begins. This finding suggests that apical constriction is not necessarily triggered by the contraction of actomyosin networks, but rather can be triggered by unidentified, temporally-regulated mechanical links between actomyosin and junctions. Here, we used C. elegans gastrulation as a model to seek genes that contribute to such dynamic linkage. We found that α-catenin and ß-catenin initially failed to move centripetally with contracting cortical actomyosin networks, suggesting that linkage is regulated between intact cadherin-catenin complexes and actomyosin. We used proteomic and transcriptomic approaches to identify new players, including the candidate linkers AFD-1/afadin and ZYX-1/zyxin, as contributing to C. elegans gastrulation. We found that ZYX-1/zyxin is among a family of LIM domain proteins that have transcripts that become enriched in multiple cells just before they undergo apical constriction. We developed a semi-automated image analysis tool and used it to find that ZYX-1/zyxin contributes to cell-cell junctions' centripetal movement in concert with contracting actomyosin networks. These results identify several new genes that contribute to C. elegans gastrulation, and they identify zyxin as a key protein important for actomyosin networks to effectively pull cell-cell junctions inward during apical constriction. The transcriptional upregulation of ZYX-1/zyxin in specific cells in C. elegans points to one way that developmental patterning spatiotemporally regulates cell biological mechanisms in vivo. Because zyxin and related proteins contribute to membrane-cytoskeleton linkage in other systems, we anticipate that its roles in regulating apical constriction in this manner may be conserved.


Subject(s)
Actomyosin , Caenorhabditis elegans , Animals , Actomyosin/genetics , Actomyosin/metabolism , Zyxin/genetics , Zyxin/metabolism , Caenorhabditis elegans/metabolism , Constriction , Proteomics , Intercellular Junctions/genetics , Intercellular Junctions/metabolism , Morphogenesis/genetics
12.
Cancer Discov ; 11(12): 3126-3141, 2021 12 01.
Article in English | MEDLINE | ID: mdl-34193440

ABSTRACT

Myeloproliferative neoplasms (MPN) are chronic blood diseases with significant morbidity and mortality. Although sequencing studies have elucidated the genetic mutations that drive these diseases, MPNs remain largely incurable with a significant proportion of patients progressing to rapidly fatal secondary acute myeloid leukemia (sAML). Therapeutic discovery has been hampered by the inability of genetically engineered mouse models to generate key human pathologies such as bone marrow fibrosis. To circumvent these limitations, here we present a humanized animal model of myelofibrosis (MF) patient-derived xenografts (PDX). These PDXs robustly engrafted patient cells that recapitulated the patient's genetic hierarchy and pathologies such as reticulin fibrosis and propagation of MPN-initiating stem cells. The model can select for engraftment of rare leukemic subclones to identify patients with MF at risk for sAML transformation and can be used as a platform for genetic target validation and therapeutic discovery. We present a novel but generalizable model to study human MPN biology. SIGNIFICANCE: Although the genetic events driving MPNs are well defined, therapeutic discovery has been hampered by the inability of murine models to replicate key patient pathologies. Here, we present a PDX system to model human myelofibrosis that reproduces human pathologies and is amenable to genetic and pharmacologic manipulation. This article is highlighted in the In This Issue feature, p. 2945.


Subject(s)
Leukemia, Myeloid, Acute , Myeloproliferative Disorders , Animals , Clonal Evolution/genetics , Disease Models, Animal , Humans , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/pathology , Mice , Mutation , Myeloproliferative Disorders/complications , Myeloproliferative Disorders/drug therapy , Myeloproliferative Disorders/genetics
14.
Nat Commun ; 10(1): 5649, 2019 12 11.
Article in English | MEDLINE | ID: mdl-31827082

ABSTRACT

Clonal hematopoiesis of indeterminate potential (CHIP) increases with age and is associated with increased risks of hematological malignancies. While TP53 mutations have been identified in CHIP, the molecular mechanisms by which mutant p53 promotes hematopoietic stem and progenitor cell (HSPC) expansion are largely unknown. Here we discover that mutant p53 confers a competitive advantage to HSPCs following transplantation and promotes HSPC expansion after radiation-induced stress. Mechanistically, mutant p53 interacts with EZH2 and enhances its association with the chromatin, thereby increasing the levels of H3K27me3 in genes regulating HSPC self-renewal and differentiation. Furthermore, genetic and pharmacological inhibition of EZH2 decreases the repopulating potential of p53 mutant HSPCs. Thus, we uncover an epigenetic mechanism by which mutant p53 drives clonal hematopoiesis. Our work will likely establish epigenetic regulator EZH2 as a novel therapeutic target for preventing CHIP progression and treating hematological malignancies with TP53 mutations.


Subject(s)
Epigenesis, Genetic , Hematologic Diseases/metabolism , Hematopoiesis , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Animals , Enhancer of Zeste Homolog 2 Protein/genetics , Enhancer of Zeste Homolog 2 Protein/metabolism , Female , Hematologic Diseases/genetics , Hematologic Diseases/physiopathology , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Histones/genetics , Histones/metabolism , Humans , Male , Methylation , Mice, Inbred C57BL , Mutation , Protein Binding
15.
Immunity ; 51(3): 479-490.e6, 2019 09 17.
Article in English | MEDLINE | ID: mdl-31402259

ABSTRACT

Natural killer (NK) cells are cytotoxic type 1 innate lymphoid cells (ILCs) that defend against viruses and mediate anti-tumor responses, yet mechanisms controlling their development and function remain incompletely understood. We hypothesized that the abundantly expressed microRNA-142 (miR-142) is a critical regulator of type 1 ILC biology. Interleukin-15 (IL-15) signaling induced miR-142 expression, whereas global and ILC-specific miR-142-deficient mice exhibited a cell-intrinsic loss of NK cells. Death of NK cells resulted from diminished IL-15 receptor signaling within miR-142-deficient mice, likely via reduced suppressor of cytokine signaling-1 (Socs1) regulation by miR-142-5p. ILCs persisting in Mir142-/- mice demonstrated increased expression of the miR-142-3p target αV integrin, which supported their survival. Global miR-142-deficient mice exhibited an expansion of ILC1-like cells concurrent with increased transforming growth factor-ß (TGF-ß) signaling. Further, miR-142-deficient mice had reduced NK-cell-dependent function and increased susceptibility to murine cytomegalovirus (MCMV) infection. Thus, miR-142 critically integrates environmental cues for proper type 1 ILC homeostasis and defense against viral infection.


Subject(s)
Homeostasis/immunology , Immunity, Innate/immunology , Lymphocytes/immunology , MicroRNAs/immunology , Animals , Cell Line , Female , HEK293 Cells , Humans , Killer Cells, Natural/immunology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Muromegalovirus/immunology , NIH 3T3 Cells , Receptors, Interleukin-15/immunology , Signal Transduction/immunology , Suppressor of Cytokine Signaling Proteins/immunology , Transforming Growth Factor beta/immunology
17.
Gastroenterol Hepatol (N Y) ; 15(2): 83-89, 2019 Feb.
Article in English | MEDLINE | ID: mdl-31011302

ABSTRACT

Nonalcoholic fatty liver disease (NAFLD) affects 75 to 100 million adults in the United States and is the leading cause of chronic liver disease worldwide, fueled by the rising epidemic of obesity and metabolic syndrome. NAFLD is the hepatic manifestation of metabolic syndrome; thus, accurately assessing and managing comorbid metabolic syndrome components is paramount. Nonalcoholic steatohepatitis (NASH) is a subset of NAFLD that includes a more progressive and advanced form of the disease, with a greater risk of fibrosis progression. Correctly diagnosing and staging NAFLD and distinguishing the subset of NASH patients is not only critical for disease monitoring and prognostication, but also holds potential implications for therapies. Although the current therapeutic landscape for NAFLD does not offer many options, future therapies are on the horizon. Properly staging the severity of disease and fibrosis is especially important when considering the eligibility and cost-effectiveness of these therapies.

18.
Psychiatry Clin Neurosci ; 72(12): 856-863, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30246448

ABSTRACT

AIM: Delirium is common and dangerous among elderly inpatients; yet, it is underdiagnosed and thus undertreated. This study aimed to test the diagnostic characteristics of a noninvasive point-of-care device with two-channel (bispectral) electroencephalography (EEG) for the screening of delirium in the hospital. METHODS: Patients admitted to the University of Iowa Hospitals and Clinics were assessed for the presence of delirium with a clinical assessment, the Confusion Assessment Method for Intensive Care Unit and Delirium Rating Scale. Subsequently, we obtained a 10-min bispectral EEG (BSEEG) recording from a hand-held electroencephalogram device during hospitalization. We performed power spectral density analysis to differentiate between those patients with and without delirium. RESULTS: Initially 45 subjects were used as a test dataset to establish a cut-off. The BSEEG index was determined to be a significant indicator of delirium, with sensitivity 80% and specificity 87.7%. An additional independent validation dataset with 24 patients confirmed the validity of the approach, with a sensitivity of 83.3% and specificity of 83.3%. CONCLUSION: In this pilot study, the BSEEG method was able to distinguish delirious patients from non-delirious patients. Our data showed the feasibility of this technology for mass screening of delirium in the hospital.


Subject(s)
Brain/physiopathology , Delirium/diagnosis , Electroencephalography/methods , Point-of-Care Systems , Aged , Aged, 80 and over , Delirium/physiopathology , Female , Humans , Male , Mass Screening , Middle Aged , Pilot Projects
19.
Cancer Res ; 78(13): 3510-3521, 2018 07 01.
Article in English | MEDLINE | ID: mdl-29724719

ABSTRACT

Point mutations in the seed sequence of miR-142-3p are present in a subset of acute myelogenous leukemia (AML) and in several subtypes of B-cell lymphoma. Here, we show that mutations associated with AML result both in loss of miR-142-3p function and in decreased miR-142-5p expression. Mir142 loss altered the hematopoietic differentiation of multipotent hematopoietic progenitors, enhancing their myeloid potential while suppressing their lymphoid potential. During hematopoietic maturation, loss of Mir142 increased ASH1L protein expression and consequently resulted in the aberrant maintenance of Hoxa gene expression in myeloid-committed hematopoietic progenitors. Mir142 loss also enhanced the disease-initiating activity of IDH2-mutant hematopoietic cells in mice. Together these data suggest a novel model in which miR-142, through repression of ASH1L activity, plays a key role in suppressing HOXA9/A10 expression during normal myeloid differentiation. AML-associated loss-of-function mutations of MIR142 disrupt this negative signaling pathway, resulting in sustained HOXA9/A10 expression in myeloid progenitors/myeloblasts and ultimately contributing to leukemic transformation.Significance: These findings provide mechanistic insights into the role of miRNAs in leukemogenesis and hematopoietic stem cell function. Cancer Res; 78(13); 3510-21. ©2018 AACR.


Subject(s)
DNA-Binding Proteins/genetics , Gene Expression Regulation, Leukemic , Histone-Lysine N-Methyltransferase/genetics , Leukemia, Myeloid, Acute/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Transcription Factors/genetics , Animals , Bone Marrow/pathology , Carcinogenesis/genetics , DNA-Binding Proteins/metabolism , Disease Models, Animal , HEK293 Cells , Hematopoietic Stem Cells/pathology , Histone-Lysine N-Methyltransferase/metabolism , Homeobox A10 Proteins , Homeodomain Proteins/metabolism , Humans , Isocitrate Dehydrogenase/genetics , Leukemia, Myeloid, Acute/pathology , Loss of Function Mutation , Mice , Mice, Inbred C57BL , Mice, Knockout , Point Mutation , Receptor, EphB2 , Signal Transduction/genetics , Transcription Factors/metabolism
20.
Nat Commun ; 9(1): 455, 2018 01 31.
Article in English | MEDLINE | ID: mdl-29386642

ABSTRACT

Hematopoietic clones harboring specific mutations may expand over time. However, it remains unclear how different cellular stressors influence this expansion. Here we characterize clonal hematopoiesis after two different cellular stressors: cytotoxic therapy and hematopoietic transplantation. Cytotoxic therapy results in the expansion of clones carrying mutations in DNA damage response genes, including TP53 and PPM1D. Analyses of sorted populations show that these clones are typically multilineage and myeloid-biased. Following autologous transplantation, most clones persist with stable chimerism. However, DNMT3A mutant clones often expand, while PPM1D mutant clones often decrease in size. To assess the leukemic potential of these expanded clones, we genotyped 134 t-AML/t-MDS samples. Mutations in non-TP53 DNA damage response genes are infrequent in t-AML/t-MDS despite several being commonly identified after cytotoxic therapy. These data suggest that different hematopoietic stressors promote the expansion of distinct long-lived clones, carrying specific mutations, whose leukemic potential depends partially on the mutations they harbor.


Subject(s)
Antineoplastic Agents/pharmacology , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/radiation effects , Leukemia/etiology , Selection, Genetic , Adolescent , Adult , Aged , Case-Control Studies , Clone Cells/drug effects , Clone Cells/radiation effects , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA Methyltransferase 3A , Female , Genes, p53 , Humans , Lymphoma/therapy , Male , Middle Aged , Multiple Myeloma/therapy , Protein Phosphatase 2C/genetics , Young Adult
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