The MUSASHI (MSI) family of RNA binding proteins (MSI1 and MSI2) contribute to a wide spectrum of cancers including acute myeloid leukemia. We find that the small molecule Ro 08-2750 (Ro) binds ...directly and selectively to MSI2 and competes for its RNA binding in biochemical assays. Ro treatment in mouse and human myeloid leukemia cells results in an increase in differentiation and apoptosis, inhibition of known MSI-targets, and a shared global gene expression signature similar to shRNA depletion of MSI2. Ro demonstrates in vivo inhibition of c-MYC and reduces disease burden in a murine AML leukemia model. Thus, we identify a small molecule that targets MSI's oncogenic activity. Our study provides a framework for targeting RNA binding proteins in cancer.
Abstract
Identification of causal variants and genes underlying genome-wide association study (GWAS) loci is essential to understand the biology of alcohol use disorder (AUD) and drinks per week ...(DPW). Multi-omics integration approaches have shown potential for fine mapping complex loci to obtain biological insights to disease mechanisms. In this study, we use multi-omics approaches, to fine-map AUD and DPW associations at single SNP resolution to demonstrate that rs56030824 on chromosome 11 significantly reduces
SPI1
mRNA expression in myeloid cells and lowers risk for AUD and DPW. Our analysis also identifies
MAPT
as a candidate causal gene specifically associated with DPW. Genes prioritized in this study show overlap with causal genes associated with neurodegenerative disorders. Multi-omics integration analyses highlight, genetic similarities and differences between alcohol intake and disordered drinking, suggesting molecular heterogeneity that might inform future targeted functional and cross-species studies.
Measurable residual disease is associated with inferior outcomes in patients with acute myeloid leukemia (AML). Measurable residual disease monitoring enhances risk stratification and may guide ...therapeutic intervention. The European LeukemiaNet working party recently came to a consensus recommendation incorporating leukemia associated immunophenotype-based different from normal approach by multi-color flow cytometry for measurable residual disease evaluation. However, the analytical approach is highly expertise-dependent and difficult to standardize. Here we demonstrate that loss of plasmacytoid dendritic cell differentiation after 7+3 induction in AML is highly specific for measurable residual disease positivity (specificity 97.4%) in a uniformly treated patient cohort. Moreover, loss of plasmacytoid dendritic cell differentiation as determined by a blast-to-plasmacytoid dendritic cell ratio >10 was strongly associated with inferior overall and relapse-free survival (RFS) Hazard ratio 2.79, 95% confidence interval (95%CI): 0.98-7.97;
=0.077) and 3.83 (95%CI: 1.51-9.74;
=0.007), respectively), which is similar in magnitude to measurable residual disease positivity. Importantly, measurable residual disease positive patients who reconstituted plasmacytoid dendritic cell differentiation (blast/ plasmacytoid dendritic cell ratio <10) showed a higher rate of measurable residual disease clearance at later pre-transplant time points compared to patients with loss of plasmacytoid dendritic cell differentiation (blast/ plasmacytoid dendritic cell ratio <10) (6 of 12, 50%
2 of 18, 11%;
=0.03). Furthermore pre-transplant plasmacytoid dendritic cell recovery was associated with superior outcome in measurable residual disease positive patients. Our study provides a novel, simple, broadly applicable, and quantitative multi-color flow cytometry approach to risk stratification in AML.
N
-methyladenosine (m
A) is an abundant nucleotide modification in mRNA that is required for the differentiation of mouse embryonic stem cells. However, it remains unknown whether the m
A ...modification controls the differentiation of normal and/or malignant myeloid hematopoietic cells. Here we show that shRNA-mediated depletion of the m
A-forming enzyme METTL3 in human hematopoietic stem/progenitor cells (HSPCs) promotes cell differentiation, coupled with reduced cell proliferation. Conversely, overexpression of wild-type METTL3, but not of a catalytically inactive form of METTL3, inhibits cell differentiation and increases cell growth. METTL3 mRNA and protein are expressed more abundantly in acute myeloid leukemia (AML) cells than in healthy HSPCs or other types of tumor cells. Furthermore, METTL3 depletion in human myeloid leukemia cell lines induces cell differentiation and apoptosis and delays leukemia progression in recipient mice in vivo. Single-nucleotide-resolution mapping of m
A coupled with ribosome profiling reveals that m
A promotes the translation of c-MYC, BCL2 and PTEN mRNAs in the human acute myeloid leukemia MOLM-13 cell line. Moreover, loss of METTL3 leads to increased levels of phosphorylated AKT, which contributes to the differentiation-promoting effects of METTL3 depletion. Overall, these results provide a rationale for the therapeutic targeting of METTL3 in myeloid leukemia.
Acquired mutations are pervasive across normal tissues. However, understanding of the processes that drive transformation of certain clones to cancer is limited. Here we study this phenomenon in the ...context of clonal hematopoiesis (CH) and the development of therapy-related myeloid neoplasms (tMNs). We find that mutations are selected differentially based on exposures. Mutations in ASXL1 are enriched in current or former smokers, whereas cancer therapy with radiation, platinum and topoisomerase II inhibitors preferentially selects for mutations in DNA damage response genes (TP53, PPM1D, CHEK2). Sequential sampling provides definitive evidence that DNA damage response clones outcompete other clones when exposed to certain therapies. Among cases in which CH was previously detected, the CH mutation was present at tMN diagnosis. We identify the molecular characteristics of CH that increase risk of tMN. The increasing implementation of clinical sequencing at diagnosis provides an opportunity to identify patients at risk of tMN for prevention strategies.
RAS-pathway mutations are recurrent events in myeloid malignancies. However, there is limited data on the significance of RAS-pathway mutations in patients with myelofibrosis (MF). We analyzed ...next-generation sequencing data of 16 genes, including RAS-pathway genes, from 723 patients with primary and secondary MF across three international centers and evaluated their significance. N/KRAS variants were present in 6% of patients and were typically sub-clonal (median VAF = 20%) relative to other genes variants. RAS variants were associated with advanced MF features including leukocytosis (p = 0.02), high somatic mutation burden (p < 0.01) and the presence of established "molecular high-risk" (MHR) mutations. MF patients with N/KRAS mutations had shorter 3-year overall survival (OS) (34% vs 58%, p < 0.001) and higher incidence of acute myeloid leukemia at 3 years (18% vs 11%, p = 0.03). In a multivariate Cox model, RAS mutations were associated with decreased OS (HR 1.93, p < 0.001). We created a novel score to predict OS incorporating RAS mutations, and it predicted OS across training and validation cohorts. Patients with intermediate risk/high-risk DIPSS with RAS mutations who received ruxolitinib had a nonsignificant longer 2-year OS relative to those who did not receive ruxolitinib. These data demonstrate the importance of identifying RAS mutations in MF patients.
Introduction Newly-diagnosed multiple myeloma (MM) patients often share tumor genetic abnormalities associated with a high risk of progression and poor survival. We hypothesized that single-cell ...transcriptomic characterization of the tumor immune microenvironment (TIME) may be combined with tumor-based risk stratification to uncover novel disease biology mechanisms associated with clinical outcomes and improve risk stratification. Methods We performed single-cell RNA sequencing of 361 CD138 negative sorted bone marrow mononuclear cells (BMMCs) samples from 263 MM patients enrolled at time of diagnosis in the Multiple Myeloma Research Foundation CoMMpass study (NCT01454297). Specimens were analyzed at baseline (n=263) across a network of five collaborating academic research centers following assay harmonization. Genetic factors that determine risk were defined as one or more of the following gain- or loss-of-function events derived from baseline genomic sequencing data: del17p14, translocations of the Ig locus with the MAF/A/B or WHSC1/MMSET/NSD2 loci, and gain of chromosome 1q21. Statistical modeling strategies were used to assess single-cell populations or RNA signatures associations with known risk factors or disease progression (FDR<0.05). Results The study generated high-quality single-cell profiles of 731,643 cells from 123 high-risk and 107 standard-risk MM patients based on genetics. Based on distinct transcriptome profiles, BMMCs formed 106 clusters corresponding to 5 major compartments: NK and T cells, B cells, erythrocytes, myeloid cells, and plasma cells. Our preliminary differential abundance analysis comparing high- vs standard-risk patients at baseline uncovered significant differences in the TIME associated with genetic risk. The high-risk group was identified as enriched in effector CD8+, and CD4+ T cells. In contrast, the high-risk group exhibited depletion of naive CD8+ and interferon-associated CD4+ and CD8+ T as compared to the standard-risk group. Within subclusters in the T and NK cells compartment, a higher cytotoxicity signature was observed in high-risk patients, characterized by the expression of granzymes and perforin. Finally, our preliminary survival and progression analysis associated a higher frequency of IDO1-expressing macrophages in worst progression patients, while better outcomes were associated with CD8+ T and B cells expressing androgen response and IL6/STAT3/EMT programs, respectively. Conclusions Current approaches for risk stratification are based on bulk measurements of tumor's genetic or epigenetics features, which do not capture the diversity and dynamics of the TIME. Through single-cell transcriptomics, we were able to capture, in high granularity, the TIME and correlate specific immune cell populations and phenotypes with relapse risk and poor prognostic outcomes. These results suggest that immune subpopulations may be an essential novel aspect for improving current risk stratification models.
Objectives: To examine gender differences in attitudes towards nutrition therapy within first- and fourth-year medical students. Methods: Participants (n=128) completed a computer self-administered ...questionnaire assessing attitudes towards nutrition therapy. Results:
Analysis of covariance revealed that females report significantly more positive attitudes toward nutrition than males do, controlling for age. The magnitude of the difference was the same in beginning and graduating medical students. Conclusions: Gender differences in attitudes towards
nutrition are not moderated by medical school socialization. Standardized nutrition education may be required to address disparities in knowledge, attitudes, and efficacy with regard to nutrition and preventive care measures.
Introduction: MF is a Philadelphia-negative myeloproliferative neoplasm (Ph-negative MPN) associated with driver mutations in the JAK-STAT pathway (e.g. JAK2, CALR, MPL) and other mutations in genes ...that lead to epigenetic changes and altered RNA splicing (e.g. TET2, SRSF2, ASXL1, EZH2). The RAS-signaling pathway is frequently altered in acute myeloid leukemia (AML) and other myeloid malignancies, but few studies have evaluated the prevalence of such mutations in patients with MF. We sought to describe the frequency and clinical features of RAS mutations in patients with MF.
Methods: We analyzed next-generation sequencing data from 723 patients with a diagnosis of primary MF (N=520), post-PV MF (N=119) and post-ET MF (N=84). Sequencing was performed with either paired tumor-normal whole exome sequencing (WES; N=56) or selected gene panel for genes associated with myeloid malignancies (N=667). The following 16 genes were analyzed in all 723 patients and were considered as the common denominator for analysis: ASXL1, CALR, DNMT3A, EZH2, FLT3, IDH1, IDH2, JAK2, KIT, KRAS, MPL, NRAS, RUNX1, TET2, TP53, WT1. RAS mutations were considered as oncogenic mutations in NRAS and/or KRAS. Molecular high risk (MHR) mutations were considered as mutations in any one of the 4 genes: ASXL1, EZH2, IDH1, IDH2 (SRSF2 mutations were not included since they were not evaluated in all cases). Odds ratio (OR) and P-values were estimated using Fisher's exact test in pairwise comparisons among genetic features, and P-values were adjusted for multiple comparisons using the Benjamini-Hochberg procedure, with significant Q-values considered as those <0.15. Overall survival (OS) was estimated using the Kaplan-Meier method, and defined as the time from the date of sample collection for mutation analysis until death from any cause, with patients alive at last follow-up censored. Cumulative incidence of AML transformation (CI-AML) was defined from the time of mutation analysis until evolution to AML, considering death without AML transformation as a competing risk. A Cox proportional hazards model was fitted to determine the hazard ratio (HR) of independent covariates associated with the dependent variable OS.
Results: Mutations in RAS genes were found in 44 patients (6.1%; 95% confidence interval CI 4.5-8.1%). There were 32 cases with NRAS mutations (4.4%; 95% CI 3-6.2%), 15 cases with KRAS mutations (2%; 95% CI 1.2-3.4%), and there were 3 cases with mutations in both genes (0.4%; 95% CI 0.1-1.3%). JAK-STAT driver genes found in the cohort included JAK2 (N=486), CALR (N=94), MPL (N=35) and Triple-negative status (N=108), and there was no difference in the distribution of JAK-STAT driver genes among patients with NRAS/KRAS mutations (p=0.96). Patients with NRAS/KRAS mutations had a higher number of non-driver mutations (median 3 vs 1; p=8.5e-20), higher white blood cell counts (median 15.1x109/L vs 10.5x109/L, p=0.02) and more frequently harbored ASXL1 mutations (OR 3.00, q=0.01), EZH2 mutations (OR 3.40, q=0.11) and MHR mutations (OR 3.13, q=0.004). There was a negative association of NRAS/KRAS mutations with del(20q) changes in karyotype (OR <0.001, q=0.06). After a median follow-up of 30 months and 439 events, OS was significantly reduced in patients harboring NRAS/KRAS mutations (median 19.5 months vs. 44.6 months, HR 2.95, p-value=5.99e-06; figure 1). The presence of NRAS/KRAS mutations was also associated with a higher CI-AML (4 years 18.4% vs. 14%, p-value=0.03). In a multivariate Cox model, NRAS/KRAS mutations were associated with worse OS after adjusting for other prognostic variables in MF (Table 1), including Dynamic International Prognostic Score System (DIPSS), karyotype and presence of MHR mutations. In a subset analysis of 396 patients with Int-2/High risk DIPSS, there were 202 patients who were treated with ruxolitinib. NRAS/KRAS mutated patients who received ruxolitinib (N=24) had superior OS than patients who did not receive the drug, but still inferior when compared to patients with wild-type NRAS/KRAS (Figure 2).
Conclusion: Patients with a diagnosis of MF who harbor NRAS/KRAS mutations comprise a high-risk subgroup with poor outcomes. NRAS/KRAS mutational status should be evaluated in future prognostic models in MF. The efficacy of JAK2 inhibitors needs to be further studied in this subgroup of patients, as well as the possibility of targeting the RAS pathway with MEK inhibitors.
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Rampal:Incyte: Honoraria, Research Funding; Jazz: Consultancy, Honoraria; Celgene: Honoraria; Stemline: Research Funding; Constellation: Research Funding. Verstovsek:Italfarmaco: Membership on an entity's Board of Directors or advisory committees; Incyte: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau.
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