[Correlation between the Promoter Methylation Status of TRIM58 and Its mRNA Expression in Acute Myeloid Leukemia].

OBJECTIVE: To analyze the relationship between the promoter methylation status of Tripartite-motif protein 58 (TRIM58) and its mRNA expression level in acute myeloid leukemia (AML), and to explore the expression and regulation of TRIM58 in AML. METHODS: The bisulfite sequencing PCR (BSP) and quantitative real-time PCR (qPCR) technologies were used to detect the promoter methylation status and expression levels of TRIM58 mRNA in primary CD34+ and CD34- AML cells and the AML cell lines KG1a and K562 were determined. RESULTS: The expression of TRIM58 mRNA in CD34+ cells was down-regulated in 10 AML patients, while that in CD34- cells was down-regulated in 12 cases. Differences in the promoter methylation level of TRIM58 were statistically significant between AML group and normal control group (P<0.05). Additionally, the expression of TRIM58 mRNA was down-regulated in cell lines KG1a and K562, and up-regulated after decitabine treatment. CONCLUSION: The down-regulation of mRNA expression of TRIM58 in AML cells may be related to its promoter methylation status.

Mitochondrial oxidative phosphorylation is dispensable for survival of CD34+ chronic myeloid leukemia stem and progenitor cells.

Chronic myeloid leukemia (CML) are initiated and sustained by self-renewing malignant CD34+ stem cells. Extensive efforts have been made to reveal the metabolic signature of the leukemia stem/progenitor cells in genomic, transcriptomic, and metabolomic studies. However, very little proteomic investigation has been conducted and the mechanism regarding at what level the metabolic program was rewired remains poorly understood. Here, using label-free quantitative proteomic profiling, we compared the signature of CD34+ stem/progenitor cells collected from CML individuals with that of healthy donors and observed significant changes in the abundance of enzymes associated with aerobic central carbonate metabolic pathways. Specifically, CML stem/progenitor cells expressed increased tricarboxylic acid cycle (TCA) with decreased glycolytic proteins, accompanying by increased oxidative phosphorylation (OXPHOS) and decreased glycolysis activity. Administration of the well-known OXPHOS inhibitor metformin eradicated CML stem/progenitor cells and re-sensitized CD34+ CML cells to imatinib in vitro and in patient-derived tumor xenograft murine model. However, different from normal CD34+ cells, the abundance and activity of OXPHOS protein were both unexpectedly elevated with endoplasmic reticulum stress induced by metformin in CML CD34+ cells. The four major aberrantly expressed protein sets, in contrast, were downregulated by metformin in CML CD34+ cells. These data challenged the dependency of OXPHOS for CML CD34+ cell survival and underlined the novel mechanism of metformin. More importantly, it suggested a strong rationale for the use of tyrosine kinase inhibitors in combination with metformin in treating CML.

[Research Advance of Gene Mutation and Targeted Drug Therapy in Childhood Acute Myeloid Leukemia --Review].

The clinical therapeutic regimen for acute myeloid leukemia (AML) is not significantly different between adults and children, which is mostly based on IA (idarubicin and cytosine arabinoside) induction chemotherapy. With the rapid development of sequencing technique, people's understandings towards the molecular and biological abnormalities of AML are increasing, diverse AML gene mutation-based targeted drugs have been rapidly developed and applied. In this review, several commonly gene mutations in AML (such as FLT3, NPM1 and C/EBPA) was described, and the therapeutic effects and differences of targeted drugs that used in clinical treatment or had been reported (like tyrosine kinase inhibitor, IDH1 mutation inhibitor and epigenetic modification inhibitor) in child and adult AML patients were summrized.