Clinical efficacy of decitabine in combination with standard-dose cytarabine, aclarubicin hydrochloride, and granulocyte colony-stimulating factor in the treatment of young patients with newly diagnosed acute myeloid leukemia

Next-generation sequencing reveals relapse and leukemia-free survival risks in newly diagnosed acute myeloid leukemia treated with CAG regimen combined with decitabine

Background

Acute myeloid leukemia (AML) is a heterogeneous hematopoietic malignancy whose prognosis is associated with several biomarkers. Decitabine, a deoxyribonucleic acid (DNA) methyltransferase (DNMT) inhibitor, combined with cytarabine, aclarubicin hydrochloride, and granulocyte colony-stimulating factor (DCAG), has been used in patients newly diagnosed with AML. This regimen has been especially used in older and fragile patients who are immunocompromised or have co-morbidities, as well as those with specific gene mutations. However, the integration of molecular risk stratification and treatment guidance for the DCAG regimen has not been well defined. Therefore, this study aimed to investigate the genetic mutations associated with AML and establish appropriate treatment strategies for patients newly diagnosed with AML.

Methods

This study analyzed the clinical data and genetic mutations based on next-generation sequencing (NGS) in 124 newly diagnosed patients with AML who received the DCAG regimen at the People's Liberation Army (PLA) General Hospital from January 2008 to August 2020. Factors associated with the cumulative incidence of relapse (CIR) and leukemia-free survival (LFS) in patients newly diagnosed with AML were analyzed.

Results

The most adverse prognosis of DCAG-treated patients was observed in those with FLT3-ITD, KIT, PTPN11, GATA2, or IDH1 mutations during univariable analysis, whereas PTPN11 mutation was solely significant in multivariable analysis, with an increased likelihood of CIR (P = 0.001) and reduced LFS duration (P = 0.077). Hyperleukocytosis was maintained as an independent risk factor for increased CIR risk (P = 0.044) and decreased LFS duration (P = 0.042) in multivariable analysis. In this study, we validated the risk classification of patients with AML receiving an epigenetic modifier-based induction regimen across a broad age range.

Conclusion

NGS demonstrated a dismal overall outcome in patients with the rare PTPN11 mutations, indicating the need for new therapies that target this high-risk subtype of AML. These results offer a potential molecular stratification and treatment guidance for patients with AML.

The m6A modulator-mediated cytarabine sensitivity and immune cell infiltration signature in acute myeloid leukemia

PURPOSE

The study aims to investigate the impact of m6A modulators on drug resistance and the immune microenvironment in acute myeloid leukemia (AML). The emergence of drug resistance is a significant factor that contributes to relapse and refractory AML, leading to a poor prognosis.

METHODS

The AML transcriptome data were retrieved from the TCGA database. The "oncoPredict" R package was utilized to assess the sensitivity of each sample to cytarabine (Ara-C) and classify them into distinct groups. Differential expression analysis was performed to identify m6A modulators differentially expressed between the two groups. Select Random Forest (RF) to build a predictive model. Model performance was evaluated using calibration curve, clinical decision curve, and clinical impact curve. The impacts of METTL3 on Ara-C sensitivity and immune microenvironment in AML were examined using GO, KEGG, CIBERSORT, and GSEA analyses.

RESULTS

Seventeen out of 26 m6A modulators exhibited differential expression between the Ara-C-sensitive and resistant groups, with a high degree of correlation. We selected the 5 genes with the highest scores in the RF model to build a reliable and accurate prediction model. METTL3 plays a vital role in m6A modification, and further analysis shows its impact on the sensitivity of AML cells to Ara-C through its interaction with 7 types of immune-infiltrating cells and autophagy.

CONCLUSION

This study utilizes m6A modulators to develop a prediction model for the sensitivity of AML patients to Ara-C, which can assist in treating AML drug resistance by targeting mRNA methylation.

Transcriptome-Wide Analysis of RNA N6-Methyladenosine Modification in Adriamycin-Resistant Acute Myeloid Leukemia Cells

Acute myeloid leukemia (AML) is one of the most aggressive hematopoietic malignancies. Patients still suffer from refractory/relapsed disease after anthracycline-based therapy, which leads to a poor prognosis. N⁶-Methyladenosine (m⁶A) is the most abundant post-transcriptional modification in eukaryotes, the imbalance of which is reported to be associated with various pathological processes, including drug resistance. However, the relationship between m⁶A modification and drug resistance has not been well defined in AML. In this study, we analyzed the sequencing data of HL60 and its Adriamycin-resistant cell line HL60/ADR. We found a total of 40,550 m⁶A-methylated peaks, representing 15,640 genes in HL60, and 38,834 m⁶A-methylated peaks, representing 15,285 genes in HL60/ADR. KEGG pathway analysis showed that pathways were enriched in the FoxO signaling pathway, p53 signaling pathway, and Notch signaling pathway. MeRIP-seq results showed that the fold enrichment of the global m⁶A level in HL60/ADR was higher than that in HL60, and dot blot assay results indicated that the global m⁶A level was elevated in HL60/ADR cells compared with that in HL60 cells. Further analysis revealed that the expression level of METTL3 was elevated in HL60/ADR cells compared with that in HL60 cells. After a combined treatment of STM2457 (an inhibitor of METTL3) and Adriamycin, the proliferation of HL60/ADR was inhibited. Thus, we hypothesized that the abnormality of m⁶A modification played an important role in Adriamycin-resistant AML.

Elevated REG3α predicts refractory aGVHD in patients who received steroids-ruxolitinib as first-line therapy

We started a single-arm, phase II, open-label, prospective clinical trial using steroids-ruxolitinib as the first-line therapy for intermediate- to high-risk aGVHD (NCT04397367). Here, we report the association of a biomarker panel (sST2, REG3α, sTNFR1, IL-6 and IL-8) with responses to GVHD therapy. The novel first-line therapy for 39 patients with newly diagnosed aGVHD consisted of 1 mg/kg methylprednisolone and 5 mg/day ruxolitinib. The serum concentrations of the biomarkers were prospectively detected at planned time points. Of the 39 patients, the complete response rate at day 28 was 82.05%. In patients who achieved CR, the concentrations of REG3α (P₁₄ = 0.01; P₂₈ = 0.10) and sTNFR1 (P₁₄ = 0.42; P₂₈ = 0.04) declined at day 14 and day 28 compared with the pre-enrolment levels. In refractory patients, the levels of REG3α at day 14 were higher than those pre-enrolment (P = 0.04). REG3α (P = 0.02) was elevated in the refractory patients compared with the patients achieving CR at day 14 after enrolment, while there was no significant difference in the levels of sST2, sTNFR1 or IL-6. Elevated REG3α levels may predict refractory aGVHD after novel first-line therapy with steroids-ruxolitinib.