Similar Datasets
Project description:Acute Myeloid Leukemia (AML) which occurs after an antecedent myeloproliferative neoplasm (MPN) has a dismal clinical prognosis and is not curative outside of the rare subset of patients who undergo successful allogeneic stem cell transplantation. As such, there is a pressing need for new mechanistic insights into how MPNs transform into AML and to use these insights to credential novel therapeutic approaches. The most common somatic mutational event which occurs in transformation from MPN to AML is mutation in TP53. However, the impact of TP53 allelic state on the ability to potentiate leukemic transformation, as well as the pathways involved in this process, have largely remained unresolved. Here we report the development of genetically accurate models of Jak2/Tp53 mutant MPN which undergoes progressive leukemic transformation with chromosomal instability similar to that observed in the clinical context. These models result in a fulminant erythroleukemia phenotype. We identify that leukemic transformation requires homozygous inactivation of TP53, and does not occur with heterozygous loss of Tp53. We further identify that the megakaryocyte erythroid progenitor (MEP) population is expanded prior to and after leukemic transformation, is characterized by progressive genomic instability (compared to other stem/progenitor compartments), and is capable of propagating the disease in vivo. Thus, the leukemia-initiating population is contained in the MEP compartment. Using gene-expression profiling we demonstrate that the BMP2/SMAD pathway (which is involved in self-renewal and DNA damage repair) is aberrantly activated in the leukemic phase of the disease. Importantly, attenuation of Bmp2 results in decreased self-renewal of leukemic cells in vitro and increased survival of leukemic mice in vivo, thus credentialing a biologic role for this pathway in leukemic transformation. Finally, given the loss of Tp53 function and associated disruption of DNA repair pathways, we hypothesized and subsequently identified that leukemic transformation is characterized by increased DNA damage. Using a synthetic-lethality strategy of targeting remaining DNA-repair pathways, using small-molecule inhibitors, in order to provoke biologically intolerable DNA damage and mitotic catastrophe, we demonstrate that Jak2/Tp53 mutant is highly sensitive to combined inhibition of WEE1 and PARP. This combination results in prolonged survival of mice and attenuates the leukemic phenotype. Collectively, these observations yield new mechanistic insights into the process of leukemic transformation resulting from TP53 alterations, and offer new, clinically-translatable, therapeutic options.
2022-05-24 | GSE180772 | GEO
Project description:Acute Myeloid Leukemia (AML) which occurs after an antecedent myeloproliferative neoplasm (MPN) has a dismal clinical prognosis and is not curative outside of the rare subset of patients who undergo successful allogeneic stem cell transplantation. As such, there is a pressing need for new mechanistic insights into how MPNs transform into AML and to use these insights to credential novel therapeutic approaches. The most common somatic mutational event which occurs in transformation from MPN to AML is mutation in TP53. However, the impact of TP53 allelic state on the ability to potentiate leukemic transformation, as well as the pathways involved in this process, have largely remained unresolved. Here we report the development of genetically accurate models of Jak2/Tp53 mutant MPN which undergoes progressive leukemic transformation with chromosomal instability similar to that observed in the clinical context. These models result in a fulminant erythroleukemia phenotype. We identify that leukemic transformation requires homozygous inactivation of TP53, and does not occur with heterozygous loss of Tp53. We further identify that the megakaryocyte erythroid progenitor (MEP) population is expanded prior to and after leukemic transformation, is characterized by progressive genomic instability (compared to other stem/progenitor compartments), and is capable of propagating the disease in vivo. Thus, the leukemia-initiating population is contained in the MEP compartment. Using gene-expression profiling we demonstrate that the BMP2/SMAD pathway (which is involved in self-renewal and DNA damage repair) is aberrantly activated in the leukemic phase of the disease. Importantly, attenuation of Bmp2 results in decreased self-renewal of leukemic cells in vitro and increased survival of leukemic mice in vivo, thus credentialing a biologic role for this pathway in leukemic transformation. Finally, given the loss of Tp53 function and associated disruption of DNA repair pathways, we hypothesized and subsequently identified that leukemic transformation is characterized by increased DNA damage. Using a synthetic-lethality strategy of targeting remaining DNA-repair pathways, using small-molecule inhibitors, in order to provoke biologically intolerable DNA damage and mitotic catastrophe, we demonstrate that Jak2/Tp53 mutant is highly sensitive to combined inhibition of WEE1 and PARP. This combination results in prolonged survival of mice and attenuates the leukemic phenotype. Collectively, these observations yield new mechanistic insights into the process of leukemic transformation resulting from TP53 alterations, and offer new, clinically-translatable, therapeutic options.
2022-05-24 | GSE180851 | GEO
Project description:The BMP2/SMAD pathway is a key regulator of TP53-altered erytholeukemia
| PRJNA749766 | ENA
Project description:The BMP2/SMAD pathway is a key regulator of TP53-altered erytholeukemia [scRNA-seq]
| PRJNA749461 | ENA
Project description:The BMP2/SMAD pathway is a key regulator of TP53-altered erytholeukemia [Bulk RNA-seq]
| PRJNA749774 | ENA
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2014-10-28 | E-GEOD-62740 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below.
2024-02-14 | GSE245412 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below.
2014-10-28 | GSE62740 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below.
2019-06-30 | GSE131466 | GEO
Project description:Leukemic transformation (LT) of myeloproliferative neoplasm (MPN) has a dismal prognosis and is largely fatal. Mutational inactivation of TP53 is the most common somatic event in LT; however, the mechanisms by which TP53 mutations promote LT remain unresolved. Using an allelic series of mouse models of Jak2/Trp53 mutant MPN, we identify that only biallelic inactivation of Trp53 results in LT (to a pure erythroleukemia [PEL]). This PEL arises from the megakaryocyte-erythroid progenitor population. Importantly, the bone morphogenetic protein 2/SMAD pathway is aberrantly activated during LT and results in abnormal self-renewal of megakaryocyte-erythroid progenitors. Finally, we identify that Jak2/Trp53 mutant PEL is characterized by recurrent copy number alterations and DNA damage. Using a synthetic lethality strategy, by targeting active DNA repair pathways, we show that this PEL is highly sensitive to combination WEE1 and poly(ADP-ribose) polymerase inhibition. These observations yield new mechanistic insights into the process of p53 mutant LT and offer new, clinically translatable therapeutic approaches.
| S-EPMC9728578 | biostudies-literature