A chest CT-based nomogram for predicting survival in acute myeloid leukemia.

BACKGROUND: The identification of survival predictors is crucial for early intervention to improve outcome in acute myeloid leukemia (AML). This study aim to identify chest computed tomography (CT)-derived features to predict prognosis for acute myeloid leukemia (AML). METHODS: 952 patients with pathologically-confirmed AML were retrospectively enrolled between 2010 and 2020. CT-derived features (including body composition and subcutaneous fat features), were obtained from the initial chest CT images and were used to build models to predict the prognosis. A CT-derived MSF nomogram was constructed using multivariate Cox regression incorporating CT-based features. The performance of the prediction models was assessed with discrimination, calibration, decision curves and improvements. RESULTS: Three CT-derived features, including myosarcopenia, spleen_CTV, and SF_CTV (MSF) were identified as the independent predictors for prognosis in AML (P < 0.01). A CT-MSF nomogram showed a performance with AUCs of 0.717, 0.794, 0.796 and 0.792 for predicting the 1-, 2-, 3-, and 5-year overall survival (OS) probabilities in the validation cohort, which were significantly higher than the ELN risk model. Moreover, a new MSN stratification system (MSF nomogram plus ELN risk model) could stratify patients into new high, intermediate and low risk group. Patients with high MSN risk may benefit from intensive treatment (P = 0.0011). CONCLUSIONS: In summary, the chest CT-MSF nomogram, integrating myosarcopenia, spleen_CTV, and SF_CTV features, could be used to predict prognosis of AML.

A novel prognostic model based on pretreatment serum albumin and ECOG PS for primary CNS lymphoma: an international, multi-center study.

BACKGROUND: Serum albumin has been demonstrated as prognostic parameter in non-Hodgkin lymphoma (NHL). Primary central nervous system lymphoma (PCNSL) is a rare extranodal NHL with highly aggressive behavior. In this study, we aimed at creating a novel prognostic model for PCNSL based on serum albumin levels. METHODS: We compared several commonly used laboratory nutritional parameters for predicting the survival of PCNSL patients using overall survival (OS) for outcome analysis and receiver operating characteristic curve analysis to determine the optimal cut-off values. Parameters associated with OS were evaluated by univariate and multivariate analyses. Independent prognostic parameters for OS were selected for risk stratification, including albumin ≤ 4.1 g/dL, ECOG PS > 1, and LLR > 166.8, which were associated with shorter OS; albumin > 4.1 g/dL, ECOG PS 0-1 and LLR ≤ 166.8, which were associated with longer OS, and five-fold cross-validation was used for evaluating predictive accuracy of identified prognostic model. RESULTS: By univariate analysis, age, ECOG PS, MSKCC score, Lactate dehydrogenase-to-lymphocyte ratio (LLR), total protein, albumin, hemoglobin, and albumin to globulin ratio (AGR) resulted statistically associated with the OS of PCNSL. By multivariate analysis, albumin ≤ 4.1 g/dL, ECOG PS > 1, and LLR > 166.8 were confirmed to be significant predictors of inferior OS. We explored several PCNSL prognostic models based on albumin, ECOG PS and LLR with 1 point assigned to each parameter. Eventually, a novel and effective PCNSL prognostic model based on albumin and ECOG PS successfully classified patients into three risk groups with 5-year survival rates of 47.5%, 36.9%, and 11.9%, respectively. CONCLUSIONS: The novel two-factor prognostic model based on albumin and ECOG PS we propose represents a simple but significant prognostic tool for assessing newly diagnosed patients with PCNSL.

Glucose partitioning in the bone marrow micro-environment in acute myeloid leukaemia.

Acute myeloid leukaemia (AML) cells metabolise glucose by glycolysis-based re-programming. However, how glucose uptake is partitioned between leukaemia cells and other cells of the bone marrow micro-environment is unstudied. We used a positron emission tomography (PET) tracer 18F fluorodeoxyglucose ([18F]-FDG) probe and transcriptomic analyses to detect glucose uptake by diverse cells in the bone marrow micro-environment in a MLL-AF9-induced mouse model. Leukaemia cells had the greatest glucose uptake with leukaemia stem and progenitor cells having the greatest glucose uptake. We also show the effects of anti-leukaemia drugs on leukaemia cell numbers and glucose uptake. Our data suggest targeting glucose uptake as a potential therapy strategy in AML if our observations are validated in humans with AML.

A novel Mcl-1 inhibitor synergizes with venetoclax to induce apoptosis in cancer cells.

BACKGROUND: Evading apoptosis by overexpression of anti-apoptotic Bcl-2 family proteins is a hallmark of cancer cells and the Bcl-2 selective inhibitor venetoclax is widely used in the treatment of hematologic malignancies. Mcl-1, another anti-apoptotic Bcl-2 family member, is recognized as the primary cause of resistance to venetoclax treatment. However, there is currently no Mcl-1 inhibitor approved for clinical use. METHODS: Paired parental and Mcl-1 knockout H1299 cells were used to screen and identify a small molecule named MI-238. Immunoprecipitation (IP) and flow cytometry assay were performed to analyze the activation of pro-apoptotic protein Bak. Annexin V staining and western blot analysis of cleaved caspase 3 were employed to measure the cell apoptosis. Mouse xenograft AML model using luciferase-expressing Molm13 cells was employed to evaluate in vivo therapeutic efficacy. Bone marrow samples from newly diagnosed AML patients were collected to evaluate the therapeutic potency. RESULTS: Here, we show that MI-238, a novel and specific Mcl-1 inhibitor, can disrupt the association of Mcl-1 with BH3-only pro-apoptotic proteins, selectively leading to apoptosis in Mcl-1 proficient cells. Moreover, MI-238 treatment also potently induces apoptosis in acute myeloid leukemia (AML) cells. Notably, the combined treatment of MI-238 with venetoclax exhibited strong synergistic anti-cancer effects in AML cells in vitro, MOLM-13 xenografts mouse model and AML patient samples. CONCLUSIONS: This study identified a novel and selective Mcl-1 inhibitor MI-238 and demonstrated that the development of MI-238 provides a novel strategy to improve the outcome of venetoclax therapy in AML.

Single-cell profiling of T cells uncovers a tissue-resident memory-like T-cell subset associated with bidirectional prognosis for B-cell acute lymphoblastic leukemia.

Introduction: The character and composition of leukemia-related T cells are closely related to the treatment response and prognosis for patients. Though B cell-acute lymphoblastic leukemia (B-ALL) patients have benefited from immune-based approaches, such as chimeric antigen receptor T cells therapy, some of them still end with poor prognosis, especially for adult patients. Therefore, deep understanding of the developmental relationship between T cell subtypes in relation to B-ALL patient prognosis is urgently needed. Methods: We analyzed the peripheral blood T cell single-cell RNA sequencing data of three B-ALL patients, using data from 11 healthy individuals as controls. In total, 16,143 and 53,701 T cells from B-ALL patients and healthy adults, respectively, were objectively analyzed for detailed delineation of 13 distinct T cell clusters. Cluster-specific genes were used as marker genes to annotate each T cell subtype. Results: Unbiased analysis enabled the discovery of circulating CD103+ T cell (CD3+CD103+MKI67+), also defined as tissue-resident memory-like T (Trm-like) cell, populations were elevated in B-ALL patients, which expressed high level of cell proliferation and exhaustion related genes. In addition, cell fate trajectory analysis showed these Trm-like cells, which shared T-cell receptor (TCR) clonotypes with exhausted T (Tex) cells and effector T (Teff) cells, were supposed to transition into Teff cells; however, mainly transformed into Tex cells in leukemia environment. More importantly, Trm-like cells transformation into Teff cells and Tex cells potentially led to favorable or poor prognosis for B-ALL patients, respectively. Conclusion: In sum, a circulating Trm-like cell subset with high level expression of cell proliferation and exhaustion related genes was elevated in B-ALL patients. The bidirectional developmental potential of these T cells into Teff or Tex is closely associated with favorable or poor prognosis, respectively. Together, our study provided a unique insight of alteration of leukemia related T cells, also showed a potential immunotherapy direction and prognosis assessment model for B-ALL patients.

Repurposing antiparasitic antimonials to noncovalently rescue temperature-sensitive p53 mutations.

The tumor suppressor p53 is inactivated by over hundreds of heterogenous mutations in cancer. Here, we purposefully selected phenotypically reversible temperature-sensitive (TS) p53 mutations for pharmacological rescue with thermostability as the compound-screening readout. This rational screening identified antiparasitic drug potassium antimony tartrate (PAT) as an agent that can thermostabilize the representative TS mutant p53-V272M via noncovalent binding. PAT met the three basic criteria for a targeted drug: availability of a co-crystal structure, compatible structure-activity relationship, and intracellular target specificity, consequently exhibiting antitumor activity in a xenograft mouse model. At the antimony dose in clinical antiparasitic therapy, PAT effectively and specifically rescued p53-V272M in patient-derived primary leukemia cells in single-cell RNA sequencing. Further scanning of 815 frequent p53-missense mutations identified 65 potential PAT-treatable mutations, most of which were temperature sensitive. These results lay the groundwork for repurposing noncovalent antiparasitic antimonials for precisely treating cancers with the 65 p53 mutations.

Increased TOX expression associates with exhausted T cells in patients with multiple myeloma.

Previous studies have shown increased aberrant expression of immune checkpoint (IC) proteins, such as programmed cell death receptor-1 (PD-1) and T cell immunoglobulin mucin-domain-containing-3 (Tim-3) on T cells from patients with multiple myeloma (MM), which result in T cell exhaustion and dysfunction. However, little is known about the mechanism regulating aberrant IC protein expression. In this study, we analyzed the expression of TOX (thymocyte selection-associated HMG BOX), a crucial transcription factor involved in T cell exhaustion, and its co-expression with PD-1, Tim-3, and CD244 in T cell subsets by multi-color fluorescent flow cytometry in peripheral blood (PB) and bone marrow (BM) samples from patients with MM. Significantly, the percentage of TOX + CD3 +/CD4 +/CD8 + T cells was increased, and similarly, higher numbers of TOX co-expression with PD-1, Tim-3, and CD244 on CD3 +/CD4 +/CD8 + T cells were found. Interestingly, the numbers of TOX +, TOX + PD-1 +, and TOX + Tim-3 + regulatory T (Treg) cells also significantly increased in both the PB and BM of MM patients. In summary, we for the first time observed increased TOX expression concurrent with PD-1, Tim-3, and CD244 on T cells, which may contribute to T cell exhaustion and impair their function in MM. Thus, TOX may be considered a potential target for reversing T cell exhaustion and improving T cell function in MM.

A Novel Prognostic Marker for Primary CNS Lymphoma: Lactate Dehydrogenase-to-Lymphocyte Ratio Improves Stratification of Patients Within the Low and Intermediate MSKCC Risk Groups.

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a highly aggressive and rare extranodal non-Hodgkin lymphoma (NHL). The MSKCC and the IELSG scores represent the most widely used prognostic models, but many changes have occurred in therapeutic protocols since their development. Moreover, many PCNSL patients cannot be classified using the IELSG score. We thus aimed to create a novel, effective and feasible prognostic model for PCNSL. METHODS: We included 248 PCNSL patients diagnosed with PCNSL. Our primary endpoint was the overall survival (OS) and we used the receiver operating characteristic (ROC) analysis to determine the optimal prognostic cut-off value for LLR (lactate dehydrogenase-to-lymphocyte ratio), neutrophil-to-lymphocyte ratio (NLR) and derived neutrophil-to-lymphocyte ratio (dNLR). Variable associated with OS were evaluated by univariate and multivariate analyses. 124 out of 248 patients were randomly selected as the internal validation cohort. RESULTS: By univariate analysis, an age >60 years, Eastern Cooperative Oncology Group performance status (ECOG PS) >1, treatment with radiotherapy alone, high-risk groups of Memorial Sloan Kettering Cancer Center (MSKCC) score, NLR >4.74, dNLR >3.29, and LLR >166.8 were significantly associated with a worse OS. By multivariate analysis, the MSKCC score and LLR were confirmed as independent prognostic parameters for poorer OS. OS, however, was not significantly different between low- and intermediate-risk groups according to the MSKCC score, while LLR proved to be prognostically relevant and was thus used to develop a novel, effective three-tier PCNSL scoring system. Of 124 patients, 84 patients with survival data and LLR data were successfully validated by newly established PCNSL LLR scoring system. CONCLUSIONS: In the present study, we demonstrate that a high LLR represents an independent unfavorable prognostic parameter in PCNSL patients which can be integrated into an effective prognostic model.

HMGCS1 drives drug-resistance in acute myeloid leukemia through endoplasmic reticulum-UPR-mitochondria axis.

Hydroxy-3-methylglutaryl-CoA synthase 1 (HMGCS1) is a key enzyme in the mevalonate pathway of cholesterol synthesis. Dysregulation of HMGCS1 expression is a common occurrence in many solid tumors. It was also found to be overexpressed in newly diagnosed (ND) and relapsed/refractory (RR) acute myeloid leukemia (AML) patients. Previous study proved that HMGCS1 could induce drug-resistance in AML cells. However, the underlying mechanism how HMGCS1 contributed to chemoresistance remains elusive. Here, we confirmed that HMGCS1 inhibitor Hymeglusin enhanced cytarabine/Adriamycin (Ara-c/ADR) chemo-sensitivity in AML cells lines. Moreover, Ara-c-resistant HL-60 cells (HL-60/Ara-c) and ADR-resistant HL-60 cells (HL-60/ADR) were more sensitive to HMGCS1 inhibition than HL-60 cells. In addition, we demonstrated that the transcription factor GATA1 was the upstream regulator of HMGCS1 and could directly bind to the HMGCS1 promoter. After treatment of Tunicamycin (Tm), the number of mitochondria was increased and the damage of endoplasmic reticulum (ER) was reduced in bone marrow cells from AML-RR patients, compared to cells from AML-CR group. HMGCS1 protected mitochondria and ER under ER stress and up-regulated unfold protein response (UPR) downstream molecules in AML cells. In summary, we proved that HMGCS1 could upregulate UPR downstream components, protect mitochondria and ER from damage in AML cells under stress, therefore conferring drug resistance. Therefore, HMGCS1 could serve as a novel target for treatment of patients with intolerant chemotherapy and AML-RR patients.

A Novel miRNA Restores the Chemosensitivity of AML Cells Through Targeting FosB.

The heterogeneous nature of acute myeloid leukemia (AML) and its poor prognosis necessitate therapeutic improvement. Current advances in AML research yield important insights regarding both AML genetics and epigenetics. MicroRNAs (miRNAs) play important roles in cell proliferation, differentiation, and survival and may be useful for AML diagnosis and prognosis. In this study, a novel miRNA, hsa-miR-12462, was identified in bone marrow (BM) samples from AML patients at diagnosis by small RNA sequencing. A significant higher level of hsa-miR-12462 was found in patients who achieve complete remission (AML-CR) after induction therapy compared with those who suffer relapse/refractory (AML-RR). FosB was predicted to be the target of hsa-miR-12462 through RNA sequencing, bioinformatics analysis, and protein-protein interaction (PPI) network analysis and then verified by luciferase activity assay. T-5224, the inhibitor of FosB, was administered to AML cell lines, which could inhibit cell proliferation, promote apoptosis, and restore the sensitivity of AML cells to cytarabine (Ara-C). In summary, a higher level of hsa-miR-12462 in AML cells is associated with increased sensitivity to Ara-C via targeting FosB.

Roles of hsa-miR-12462 and SLC9A1 in acute myeloid leukemia.

MicroRNAs (miRNAs) play important roles in cell proliferation, differentiation, and survival and may be useful for acute myeloid leukemia (AML) diagnosis and prognosis. In this study, we defined a novel miRNA, hsa-miR-12462, through small RNA sequencing of the bone marrow (BM) cells from 128 AML patients. Overexpression of hsa-miR-12462 in AML cells (U937 and HL-60) significantly decreased their growth rate when compared with those of the wild-type and MOCK controls. In a xenograft mouse model, tumor weight and size in the mice bearing the U937 cells with hsa-miR-12462 overexpression were significantly reduced when compared with those bearing the mock cells. The AML cells overexpressing hsa-miR-12462 had increased sensitivity to cytarabine chemotherapy. Combining the data from the MiRDB, an online microRNA database ( http://mirdb.org ), with the RNA-sequencing results, SLC9A1 was predicted to be one of the targets of hsa-miR-12462. hsa-miR-12462 was further confirmed to bind exclusively to the 3'UTR of SLC9A1 in U937 cells, leading to downregulation of SLC9A1. In summary, a higher level of hsa-miR-12462 in AML cells is associated with increased sensitivity to cytarabine chemotherapy via downregulation of SLC9A1.

CDK6 Is a Potential Prognostic Biomarker in Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) is a threatening hematological malignant disease in which new successful approaches in therapy are needed. Cyclin-dependent kinase 6 (CDK6), a regulatory enzyme of the cell cycle that plays an important role in leukemogenesis and the maintenance of leukemia stem cells (LSC), has the potential to predict the prognosis of AML. By analyzing public databases, we observed that the messenger RNA (mRNA) levels of CDK6 were significantly overexpressed in AML cell lines and non-acute promyelocytic leukemia (non-APL) AML patients when compared to healthy donors. Furthermore, CDK6 expression was significantly reduced in AML patients who achieved complete remission (CR) compared to that at the time of diagnosis in our validated cohort. The expression of CDK6 was tightly correlated with peripheral blood blasts, French-American-British (FAB) subtypes, CCAAT-enhancer-binding protein α (CEBPA) mutation, and chromosomal abnormalities of t(8;21). However, the clinical significance and effects of CDK6 expression on the prognosis of non-APL AML patients remain uncertain. We found that CDK6 expression was inversely correlated with overall survival (OS) among non-APL AML patients using the Kaplan-Meier analysis. CDK6 was also found to be positively associated with genes identified to contribute to the development of leukemia, including CCND2, DNMT3B, SOX4, and IKZF2, as well as being negatively associated with anticancer microRNAs, including miR-187, miR-9, miR-582, miR708, and miR-362. In summary, our study revealed that CDK6 might be a potential diagnostic and prognostic biomarker in non-APL AML patients.

The role of cholesterol metabolism in leukemia.

Leukemia is a common hematological malignancy with overall poor prognosis. Novel therapies are needed to improve the outcome of leukemia patients. Cholesterol metabolism reprogramming is a featured alteration in leukemia. Many metabolic-related genes and metabolites are essential to the progress and drug resistance of leukemia. Exploring potential therapeutical targets related to cholesterol homeostasis is a promising area. This review summarized the functions of cholesterol and its derived intermediate metabolites, and also discussed potential agents targeting this metabolic vulnerability in leukemia.

SUMOylation of insulin-like growth factor 1 receptor, promotes proliferation in acute myeloid leukemia.

Current valid treatments for acute myeloid leukemia (AML) include chemotherapy and hematopoietic stem cell transplantation, which are defective and limited respectively. The insulin-like growth factor 1 receptor (IGF-1R) is up-regulated in many solid tumors; therefore, it may be a target for tumor therapy. Interestingly, IGF-1R is modified by SUMOylation, a type of reversible post-translational modification. In this study, we found that IGF-1R was increased in both cell lines and clinical samples of AML and was modified by SUMO-1. Furthermore, IGF-1, ligand of IGF-1R, induced the up-regulation of IGF-1R and increased the proliferation of leukemia cell line. After mutation of Lys(1025) and Lys(1100) in IGF-1R, the evolutionarily conserved lysine residues were identified as the SUMOylation sites of IGF-1R, because the SUMOylation of IGF-1R in these mutants was significantly inhibited. Furthermore, the cell proliferation mediated by IGF-1 was also reduced. After inhibition of UBC9, the activating enzyme of SUMOylation, co-expression of IGF-1R and SUMO-1 was down-regulated, and cell proliferation was also inhibited. However, cell apoptosis was not significantly affected. These results suggest that IGF-1R and its SUMOylation may be a new therapeutic target for strategy of AML.

MicroRNA-20b and ERK1/2 pathway independently regulate the expression of tissue factor in hematopoietic and trophoblastic differentiation of human embryonic stem cells.

INTRODUCTION: Tissue factor (TF) is expressed in various types of cells. TF expression is essential for many biological processes, such as blood coagulation and embryonic development, while its high expression in stem cells often leads to failure of transplantation. In this study, we used the human embryonic stem cell (hESC) culture system to understand the molecular mechanisms by which TF expression is regulated in hESC-derived hematopoietic and trophoblastic cells. METHODS: hESCs were induced in vitro to differentiate into hematopoietic and trophoblastic cells. TF expression in various types of cells during these differentiation processes was examined by quantitative real-time polymerase chain reaction analysis and western blot analysis. The regulatory mechanisms of TF expression were investigated by miRNA expression analysis, luciferase report assay, TF mRNA and protein analysis, and pathway phosphorylation analysis. RESULTS: We first found that TF was expressed only in trophoblasts and granulocyte-monocyte (G-M) cells differentiated from hESCs; and then demonstrated that miR-20b downregulated and Erk1/2 signaling pathway upregulated the TF expression in trophoblasts and G-M cells. Finally, we found that miR-20b downregulated the TF expression independently of the Erk1/2 signaling pathway. CONCLUSIONS: The miR-20b and Erk1/2 pathway independently regulate expression of TF in trophoblasts and G-M cells differentiated from hESCs. These findings will open an avenue to further illustrate the functions of TF in various biological processes.