Mutation profile and associated clinical features in Chinese patients with cytogenetically normal acute myeloid leukemia

Wilms' tumor gene 1 in hematological malignancies: friend or foe?

Wilms' tumor gene 1 (WT1) is a transcription and post-translational factor that has a crucial role in the biological and pathological processes of several human malignancies. For hematological malignancies, WT1 overexpression or mutation has been found in leukemia and myelodysplastic syndrome. About 70-90% of acute myeloid leukemia patients showed WT1 overexpression, and 6-15% of patients carried WT1 mutations. WT1 has been widely regarded as a marker for monitoring minimal residual disease in acute myeloid leukemia. Many researchers were interested in developing WT1 targeting therapy. In this review, we summarized biological and pathological functions, correlation with other genes and clinical features, prognosis value and targeting therapy of WT1 in hematological features.

Leonurus japonicus Houttuyn induces reactive oxygen species-mediated apoptosis via regulation of miR-19a-3p/PTEN/PI3K/AKT in U937 and THP-1 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Leonurus japonicus Houttuyn is a medicinal ingredient in more than 300 prescriptions in traditional Korean medicine. It is especially important for women's health and blood-related diseases. Recent research revealed that Leonurus japonicus Houttuyn extracts have antioxidative, anticancer, analgesic, anti-inflammatory, and neuroprotective properties.

AIM OF THE STUDY

However, its underlying anti-cancerous mechanisms remain unclear. This study elucidated the anticancer mechanism of Leonurus japonicus Houttuyn in U937 and THP-1 cancer cells.

MATERIALS AND METHODS

High-performance liquid chromatography (HPLC) was used for detecting main compound of Leonurus japonicus Houttuyn, rutin. EZ-Cytox cell viability assay, Western blot analysis, live and dead cell assay, 2', 7' dichlorofluorescin diacetate (DCFDA) assay, quantitative real-time PCR (qRT-PCR) analysis, and microRNA (miR) mimic transfection assay were applied to further investigate anti-cancer efficacies and underlying mechanism in U937 and THP-1 cells.

RESULTS

The main compound of Leonurus japonicus Houttuyn, rutin was detected using HPLC. The cytotoxic effect of Leonurus japonicus Houttuyn was exerted in U937 and THP-1 cancer cells but not in MDBK and IEC-6 normal cells. Leonurus japonicus Houttuyn decreased mitochondria membrane potential (ΔΨm). Consistently, Leonurus japonicus Houttuyn reduced the expression of survivin and cleaved caspase-9, caspase-3, and poly (ADP-ribose) polymerase (PARP). Cell death was increased in Leonurus japonicus Houttuyn treated groups. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and CCAAT-enhancer-binding protein homologous protein (CHOP) was increased and phosphatidylinositol-3-kinase (PI3K) and Protein kinase B (AKT) were decreased by Leonurus japonicus Houttuyn. Reactive oxygen speices generation was elevated by Leonurus japonicus Houttuyn and its cytotoxicity was reversed by N-acetyl-l-cysteine (NAC) pretreatment. Moreover, onco-microRNA (miR), miR-19a-3p was suppressed by Leonurus japonicus Houttuyn and transfection of miR-19a-3p mimic reversed the regulated PTEN, p-AKT, CHOP expression, attenuating Leonurus japonicus Houttuyn induced apoptosis.

CONCLUSIONS

These findings indicated that Leonurus japonicus Houttuyn has anti-cancer effects by regulation of PTEN/PI3K/AKT signal pathway and ROS-related ER stress-induced apoptosis via regulation of miR-19a-3p. Leonurus japonicus Houttuyn may be an effective candidate for triggering PTEN-dependent apoptosis of cancer cells related to acute myeloid leukemia.

The Application of Targeted RNA Sequencing for KMT2A-Partial Tandem Duplication Identification and Integrated Analysis of Molecular Characterization in Acute Myeloid Leukemia

The partial tandem duplication of histone-lysine N-methyltransferase 2A (KMT2A-PTD) is an important genetic alteration in acute myeloid leukemia (AML) and is associated with poor clinical outcome. Accurate and rapid detection of KMT2A-PTD is important for outcome prediction and clinical management, but next-generation sequencing-based quantitative research is still lacking. In this study, we developed a targeted RNA-based next-generation sequencing panel, together with single primer enrichment and unique molecular identifiers, to identify KMT2A-PTD as well as AML-related gene fusions and other driver mutations. Our panel showed high sensitivity, accuracy, and reproducibility in detecting the fusion ratio of KMT2A-PTD. We characterized the mutation profile of KMT2A-PTD-positive patients with AML and found different distribution patterns of driver mutations according to KMT2A-PTD fusion ratio level. Survival analyses revealed that the fusion ratio of KMT2A-PTD did not affect clinical outcome, but a novel molecular combination, namely, KMT2A-PTD/DNMT3A/FMS-like tyrosine kinase 3-internal tandem duplication, was associated with poor prognosis. Finally, we proved that the dynamic changes in the KMT2A-PTD fusion ratio were consistent with the overall process of disease progression. In summary, we applied the unique molecular identifier-based RNA panel to quantitatively detect KMT2A-PTD and elucidate its clinical relevance, which complemented the integrative network of various genetic alterations in AML.

Novel insights of acute myeloid leukemia with CEBPA deregulation: Heterogeneity dissection and re-stratification

Acute myeloid leukemia with bi-allelic CEBPA mutation was categorized as an independent disease entity with favorable prognosis, however, recent researches have revealed huge heterogeneity within this disease group, and for some patients, relapse remained a major cause of treatment failure. Further risk stratification is essentially needed. Here by reviewing the latest literature, we summarized the characteristics of CEBPA mutation profiles and clinical features, with a special intention of dissecting the heterogeneity within the seemingly homogeneous AML with bi-allelic CEBPA mutations. Specifically, non-classical CEBPA mutation, miscellaneous companion genetic aberrations and the presence of germline CEBPA mutation are three major sources of heterogeneity. Identifying these factors can help us predict patients at a higher risk of relapse, for whom aggressive treatment may be recommended. Novel therapeutic approaches regarding manipulating potentially druggable targets as well as the debate over post remission consolidation regimens has also been discussed.

Comparison of gene mutation spectra in younger and older Chinese acute myeloid leukemia patients and its prognostic value

Differences in the gene mutation spectra of younger and older Chinese adult AML patients and the prognostic significance of these differentially presented gene mutations are rarely reported. One hundred and thirteen newly diagnosed Chinese adults with AML, divided into groups of younger and older patients, were enrolled in this study. Bone marrow samples from the patients were analyzed using targeted next-generation sequencing with a panel of 141 genes. Ninety-eight mutated genes were detected and the top 10 mutated genes were KMT2D, FLT3, FAT1, ASXL1, NRAS, DNMT3A, RELN, TET2, JAK2, and KRAS. The top five functional groups were the tyrosine kinase pathway, transcription factors, DNA methylation, chromatin modifiers, and the JAK-STAT signaling pathway. Younger patients exhibited higher incidences of KMT2D (33.8% vs 10.4%, P = 0.004) and KRAS (15.4% vs 2.1%, P = 0.042) mutations than older patients; whereas, older patients harbored more SRSF2 (20.8% vs 0%, P = 0.002), transcription factor (85.4% vs 67.7%, P = 0.031), DNA methylation (58.3% vs 36.9%, P = 0.024), and RNA splicing (31.3% vs 12.3%, P = 0.013) mutations than younger patients. Moreover, patients with SRSF2 mutations exhibited a lower rate of overall survival (P < 0.001) and relapse-free survival (P < 0.001) than patients carrying wild-type SRSF2. In conclusion, rarely reported KMT2D, FAT1, and RELN mutations were detected at high frequencies in our cohort. The gene mutation spectrum of older patients was different to that of younger patients. Moreover, older patients harbored more SRSF2 mutations, which predicted lower rates of overall and relapse-free survival.

Mutation profile and prognostic relevance in elderly patients with de novo acute myeloid leukemia treated with decitabine-based chemotherapy

INTRODUCTION

Decitabine-based chemotherapy regimens have shown efficacy in the treatment of elderly patients with acute myeloid leukemia (AML). However, it remains unclear whether any molecular alteration is correlated with the therapeutic effect of such treatment regimens.

METHODS

Gene mutations were detected using next-generation sequencing, and their impact on survival was investigated in elderly AML patients receiving decitabine-based chemotherapy.

RESULTS

A higher incidence of gene mutations was identified in elderly AML patients than in the younger cohorts. Elderly patients more frequently carried DNMT3A, IDH2, ASXL1, TET2, RUNX1, CEBPA single mutation (CEBPA^single-mut ), and TP53 mutations. Survival analysis showed that DNMT3A, FLT3-ITD, and TP53 mutations were associated with inferior overall survival (OS) and event-free survival (EFS) in younger AML patients receiving standard treatment. However, in elderly patients treated with decitabine-based chemotherapy, FLT3-ITD, and ASXL1 mutations, but not DNMT3A and TP53 mutations, were associated with poor OS and EFS. Moreover, contrary to CEBPA double mutation (CEBPA^double-mut ), CEBPA^single-mut was identified as an unfavorable prognostic factor.

CONCLUSION

This study comprehensively analyzed the prognostic implications of gene mutations in elderly AML patients under decitabine-based treatment modality. Identification of genetic biomarkers to predict the subgroup of elderly AML patients who can benefit from decitabine-based regimens might have an immediate clinical utility to optimize the treatment of elderly AML patients.

Identification of a t(X;17)(q28;q21) generating a KANSL1-MTCP1 gene fusion leading to dysregulated expression of MTCP1 in acute myeloid leukemia

Chromosomal translocations and generating fusion genes are closely associated with disease initiation and progression in acute myeloid leukemia (AML). In this study, we identified a novel t(X;17)(q28;q21) chromosomal rearrangement in a patient with acute monocytic leukemia. Using RNA-sequencing, we identified a KANSL1-MTCP1 and a KANSL1-CMC4 fusion gene. 5'-UTR sequences of the KANSL1 gene were found to become fused upstream of the coding sequence region of the MTCP1 and CMC4 genes, respectively, resulting in an aberrantly high expression of these genes. Functional studies revealed that overexpression of the MTCP1 gene induced an increased cell proliferation and partial blockage of cell differentiation, suggesting that the aberrant expression of MTCP1 is of critical importance in leukemogenesis.