Performance of a novel eight-color flow cytometry panel for measurable residual disease assessment of chronic lymphocytic leukemia.

BACKGROUND: Measurable residual disease (MRD) is an important prognostic indicator of chronic lymphocytic leukemia (CLL). Different flow cytometric panels have been developed for the MRD assessment of CLL in Western countries; however, the application of these panels in China remains largely unexplored. METHODS: Owing to the requirements for high accuracy, reproducibility, and comparability of MRD assessment in China, we investigated the performance of a flow cytometric approach (CD45-ROR1 panel) to assess MRD in patients with CLL. The European Research Initiative on CLL (ERIC) eight-color panel was used as the "gold standard." RESULTS: The sensitivity, specificity, and concordance rate of the CD45-ROR1 panel in the MRD assessment of CLL were 100% (87/87), 88.5% (23/26), and 97.3% (110/113), respectively. Two of the three inconsistent samples were further verified using next-generation sequencing. In addition, the MRD results obtained from the CD45-ROR1 panel were positively associated with the ERIC eight-color panel results for MRD assessment (R = 0.98, p < 0.0001). MRD detection at low levels (≤1.0%) demonstrated a smaller difference between the two methods (bias, -0.11; 95% CI, -0.90 to 0.68) than that at high levels (>1%). In the reproducibility assessment, the bias was smaller at three data points (within 24, 48, and 72 h) in the CD45-ROR1 panel than in the ERIC eight-color panel. Moreover, MRD levels detected using the CD45-ROR1 panel for the same samples from different laboratories showed a strong statistical correlation (R = 0.99, p < 0.0001) with trivial interlaboratory variation (bias, 0.135; 95% CI, -0.439 to 0.709). In addition, the positivity rate of MRD in the bone marrow samples was higher than that in the peripheral blood samples. CONCLUSIONS: Collectively, this study demonstrated that the CD45-ROR1 panel is a reliable method for MRD assessment of CLL with high sensitivity, reproducibility, and reliability.

[The Expression Level and Diagnostic Value of Serum Free Light Chain in B-Cell Non-Hodgkin Lymphoma].

OBJECTIVE: To investigate the expression level and the diagnostic value of serum free light chain in B-cell non-Hodgkin's lymphoma (B-NHL). METHODS: We retrospectively analyzed the results of serum free light chain (sFLC) of 394 newly treated B-NHL patients in our hospital from January 2014 to December 2021 and compared the secretion levels of sFLC among different subtypes of B-NHL. The value of sFLC secretion levels in the diagnosis of WM was evaluated using ROC. RESULTS: Increased proportion of sFLC, abnormal ratio of sFLC (κ / λ) and the secretion levels of sFLC (κ+λ) were different in different B-NHL subtypes, Waldenstrom's macroglobulinemia (WM) had the highest proportion of elevated sFLC(82.68%) and abnormal sFLC(κ/ λ)(87.0%), the proportion of FL(18.0%) and DLBCL patients(12.8%) with elevated sFLC was lower (P<0.05). The expression levels of sFLC can helpful in the diagnosis of WM (AUC=0.874，P<0.001， 95% CI: 0.779-0.970). At the same time, higher sFLC levels and sFLC cloning patterns predicted the possibility of bone marrow infiltration of lymphoma. CONCLUSION: The serum free light chains is common in patients with B-NHL. The elevated level and type of free light chain are associated with the type of lymphoma, and the patients with bone marrow infiltration have higher sFLC（κ+ λ） expression level.

CARMA1 is required for Notch1-induced NF-κB activation in SIL-TAL1-negative T cell acute lymphoblastic leukemia.

The NF-κB signaling pathway is an important downstream pathway of oncogenic Notch1 in T cell acute lymphoblastic leukemia (T-ALL) cells. However, the molecular mechanisms underlying the cascade activation of Notch1 in T-ALL cells are poorly understood. Here, we evaluated the role of CARMA1 in Notch1-induced NF-κB activation in T-ALL cells. CARMA1 was highly and specifically expressed in T-ALL cells and correlated with the prognosis of T-ALL patients. Interestingly, CARMA1 knockdown only inhibited the growth and proliferation of SIL-TAL1 fusion gene-negative T-ALL cells. In addition, CARMA1 knockdown arrested T-ALL cells at the G1 phase. Furthermore, CARMA1 knockdown significantly inhibited the proliferation of T-ALL cells in vivo and prolonged the survival of mice. Mechanistically, CARMA1 deficiency abolished Notch1-induced NF-κB transcriptional activation and significantly reduced expression levels of the NF-κB target genes c-Myc, Bcl-2, and CCR7. Taken together, these results of our study identify CARMA1 as one of the crucial mediators of Notch1-induced transformation of T-All cells, suggesting that CARMA1 is a promising therapeutic target for T-ALL due to its specific expression in lymphocytes. KEY MESSAGES: CARMA1 contributes to cell survival only in SIL-TAL1 negative T-ALL cells. CARMA1 is a crucial mediator of Notch1-induced activation of NF-κB pathway. CARMA1 is a promising therapeutic target for T-ALL.

MALT1 Inhibition as a Therapeutic Strategy in T-Cell Acute Lymphoblastic Leukemia by Blocking Notch1-Induced NF-κB Activation.

Current treatment of T-cell acute lymphoblastic leukemia (T-ALL) is primarily based on high-intensity combination chemotherapy, which has serious side effects. Therefore, developments of novel targeted therapeutics are urgently needed for treatment of T-ALL. In this study, we found that mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) is a novel promising therapeutic target for treatment of T-ALL. MALT1 inhibitor MI-2 significantly suppressed the cell growth, proliferation, and colony formation of T-ALL cells. Furthermore, MI-2 induced cell apoptosis of T-ALL via a mitochondrial-dependent pathway. In a T-ALL mouse model, MI-2 significantly reduced leukemic burden and prolonged the survival of leukemia-bearing mice. Mechanistically, MALT1 inhibition effectively blocked both baseline and Notch1-induced activation of nuclear factor κB pathway, which mediates T-ALL cell survival. In conclusion, our results highlight the potential role of MALT1 as an attractive target for treatment of T-ALL and support the potential of MI-2 or other MALT1 inhibitors to clinical trials in T-ALL.

MiR-340 Is a Biomarker for Selecting Treatment Between Chemotherapy and Allogeneic Transplantation in Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) requires refined risk stratification tools to drive decisions concerning effective therapeutic strategies. Here, genome-wide screening was carried out for identifying miRNA molecules capable of predicting treatment outcome in AML patients based on the TCGA dataset. We identified miR-340 as a prognostic factor for selecting treatment between chemotherapy and allogeneic transplantation (allo-HSCT). In multivariable analyses, low miR-340 expression independently predicted reduced OS (HR = 2.07, P = 0.004) and EFS (HR = 1.909, P = 0.01) independent of other well-known prognostic factors. Meanwhile, allo-HSCT overcome deleterious outcomes related to low miR-340. Cases administered allo-HSCT showed markedly improved OS (HR = 0.316, P < 0.0001) and EFS (HR = 0.391, P = 0.002) in comparison with those receiving chemotherapy in the low miR-340 group. Gene expression assessment revealed that elevated miR-340 amounts were negatively correlated with HOXA/HOXB cluster levels, as well as the amounts of the HOX cofactor MEIS1. Strikingly, in silico analysis pointing to HOXA10, HOXB2, and MEIS1 as miR-340 targets. The miR-340 expression may help identify cases requiring strategies for selecting the optimal therapeutic option between chemotherapy and allo-HCST. AML cases showing low miR-340 levels should be strongly considered for early allo-HSCT treatment.

Selective inhibition of Aurora A and B kinases effectively induces cell cycle arrest in t(8;21) acute myeloid leukemia.

The fusion gene AML1-ETO initially dysregulates various cell cycle molecules in t(8;21) acute myeloid leukemia. Aurora kinases have shown great promise in treating tumors. However, the efficacy of Aurora kinase (AURK) A and B inhibition in t(8;21) AML remains unclear. We found that AURK-A inhibitor Alisertib and AURK-B inhibitor Barasertib strongly inhibited the growth and proliferation of t(8;21) AML cells. The quantity and size of cell colonies were markedly decreased after a 14-d drug exposure. The cell cycle distribution was blocked at the G2/M phase in both dose- and time-dependent manner. The expression of p53 family and cdc2-p34 significantly changed as well. Notably, we found that t(8;21) AML cells are more sensitive to Aurora B inhibition. In each set of experiments, Barasertib took less time or a lower concentration to achieve similar efficacy. Taken together, our data highlighted the potential role of Aurora kinases as promising cell cycle targets for the treatment of t(8;21) AML and hereby provided a theoretical basis to guide relevant clinical trials.

High expression of miR-25 predicts favorable chemotherapy outcome in patients with acute myeloid leukemia.

BACKGROUND: Acute myeloid leukemia (AML) pertains to a hematologic malignancy with heterogeneous therapeutic responses. Improvements in risk stratification in AML patients are warranted. MicroRNAs have been associated with the pathogenesis of AML. METHODS: To examine the prognostic value of miR-25, 162 cases with de novo AML were classified into two groups according to different treatment regimens. RESULTS: In the chemotherapy group, cases with upregulated miR-25 expression showed relatively longer overall survival (OS; P = 0.0086) and event-free survival (EFS; P = 0.019). Multivariable analyses revealed that miR-25 upregulation is an independent predictor for extended OS (HR = 0.556, P = 0.015) and EFS (HR = 0.598, P = 0.03). In addition, allogeneic hematopoietic stem cell transplantation (allo-HSCT) circumvented the poor prognosis that was related to miR-25 downregulation with chemotherapy. The expression level pattern of miR-25 coincided with AML differentiation and proliferation, which included HOXA and HOXB cluster members, as well as the HOX cofactor MEIS1. The MYH9 gene was identified as a direct target of miR-25. CONCLUSIONS: The miR-25 levels are correlated with prognosis in AML independently of other powerful molecular markers. The expression of miR-25 may contribute to the selection of the optimal treatment regimen between chemotherapy and allo-HCST for AML patients.

High expression of miR-338 is associated with poor prognosis in acute myeloid leukemia undergoing chemotherapy.

Acute myeloid leukemia (AML) is a heterogeneous disease with unfavorable outcomes. MicroRNAs (miRNAs) are important regulators and prognostic factors involved in AML. To determine the clinical role of miR-338 in AML, a total of 164 adults with de novo AML were collected. These patients were classified into a chemotherapy group and an allogeneic hematopoietic stem cell transplantation (allo-HSCT) group according to the clinical treatment, and then each group was divided into two subgroups based on the median miR-338 expression values. We found that upregulated miR-338 positively correlates with higher frequencies of complex karyotype, RUNX1 mutation, and poor risk status. In the chemotherapy group, high expression of miR-338 was independently associated with shorter EFS and OS. However, no significant differences were observed between the two subgroups within the allo-HSCT group. We also divided all patients into two groups according to the median miR-338 expression values of the whole cohort. In the miR-338 high expression group, patients receiving allo-HSCT had longer OS and EFS than those receiving chemotherapy only. In contrast, patients receiving different therapies had similar OS and EFS in the miR-338 low expression group. Our study suggests that high expression of miR-338 is an adverse prognostic biomarker in patients with AML undergoing chemotherapy and may guide treatment decisions for AML. Furthermore, allo-HSCT could significantly overcome the negative effect of high miR-338 expression, but it seemed to be unbeneficial and unnecessary for low miR-338 expressions.

High expression of miR-363 predicts poor prognosis and guides treatment selection in acute myeloid leukemia.

BACKGROUND: Acute myeloid leukemia (AML) is a highly heterogeneous malignancy with various outcomes, and therefore needs better risk stratification tools to help select optimal therapeutic options. METHODS: In this study, we identify miRNAs that could predict clinical outcome in a heterogeneous AML population using TCGA dataset. RESULTS: We found that MiR-363 is a novel prognostic factor in AML patients undergoing chemotherapy. In multivariable analyses, high miR-363 remained predictive for shorter OS (HR = 2.349, P = 0.012) and EFS (HR = 2.082, P = 0.001) independent of other well-known prognostic factors. More importantly, allogeneic hematopoietic stem cell transplantation (allo-HSCT) overcame the adverse outcomes related to high miR-363 expression. In gene expression profiling, high miR-363 expression was positively correlated with the amounts of leukemogenic transcription factors, including Myb, RUNX3, GATA3, IKZF3, ETS1 and MLLT3. Notably, we found that the in silico predicted target genes (EZH2, KLF6 and PTEN) of miR-363 were downregulated in association with high miR-363 expression. CONCLUSIONS: In summary, miR-363 expression may help identify patients in need of strategies to select the optimal therapy between chemotherapeutic and allo-HCST regimens. AML patients with high miR-363 expression may be highly recommended for early allo-HSCT regimen.

MiR-425 expression profiling in acute myeloid leukemia might guide the treatment choice between allogeneic transplantation and chemotherapy.

BACKGROUND: Acute myeloid leukemia (AML) is a highly heterogeneous disease. MicroRNAs function as important biomarkers in the clinical prognosis of AML. METHODS: This study identified miR-425 as a prognostic factor in AML by screening the TCGA dataset. A total of 162 patients with AML were enrolled for the study and divided into chemotherapy and allogeneic hematopoietic stem cell transplantation (allo-HSCT) groups. RESULTS: In the chemotherapy group, patients with high miR-425 expression had significantly longer overall survival (OS) and event-free survival (EFS) compared with patients with low miR-425 expression. In multivariate analyses, high miR-425 expression remained independently predictive of a better OS (HR = 0.502, P = 0.005) and EFS (HR = 0.432, P = 0.001) compared with patients with low miR-425 expression. Then, all patients were divided into two groups based on the median expression levels of miR-425. Notably, the patients undergoing allo-HSCT had significantly better OS (HR = 0.302, P < 0.0001) and EFS (HR = 0.379, P < 0.0001) compared with patients treated with chemotherapy in the low-miR-425-expression group. Mechanistically, high miR-425 expression levels were associated with a profile significantly involved in regulating cellular metabolism. Among these genes, MAP3K5, SMAD2, and SMAD5 were predicted targets of miR-425. CONCLUSIONS: The expression of miR-425 may be useful in identifying patients in need of strategies to select the optimal therapy between chemotherapy and allo-HSCT treatment regimens. Patients with low miR-425 expression may consider early allo-HSCT.