Effective treatment of low-dose decitabine in myelodysplastic syndrome/myeloproliferative neoplasms

Systemic vasculitis successfully treated with decitabine in a high-risk myelodysplastic syndrome patient: a case report and literature review

Aim: Epidemiological studies have reported the association between myelodysplastic syndrome (MDS) and autoimmune diseases (AIDs). Immune dysregulation appears as the common driving force between MDS and AIDs pathogenesis. Low-dose hypomethylating agents might suppress tumor growth and regulate immune balance via its epi-immunomodulatory role. Materials & methods: A high-risk MDS patient presented with systemic vasculitis and was successfully treated with ultra-low-dose decitabine (7 mg/m²/d for 5 days). Results: He achieved complete remission of both MDS and AIDs after two cycles of decitabine treatment, and his overall survival duration was 45 months. Conclusion: Future studies should assess the application of ultra-low-dose decitabine among some high-risk MDS patients, especially among those with comorbid AIDs or in cases warranting the prevention of decitabine-mediated myelosuppression.

Changes in IDH2, TET2 and KDM2B Gene Expression After Treatment With Classic Chemotherapeutic Agents and Decitabine in Myelogenous Leukemia Cell Lines

Background

Hematological malignancies are a heterogeneous group of tumors with increased proliferative and auto-replicative capacity. Despite treatment advances, post-treatment quality of life remains highly affected. Studies addressing the molecular mechanisms of these diseases are critical for the development of effective, rapid and selective therapies, since few therapeutic strategies succeed in being effective without triggering high-grade toxicities or debilitating late effects. Our aim of this study was to verify changes in the expression of genes involved in the malignant phenotype of hematological malignancies, by treating human cell lines in vitro with classic chemotherapeutic agents and the demethylating agent, decitabine.

Methods

KASUMI-1 and K-562 human myeloid leukemia cell lines were plated at a density of 3 × 10⁴ cells/well and treated with increasing concentrations of different chemotherapeutic agents commonly used in the clinical setting. After 24 and 48 h of treatment, cell viability was tested, and RNA was extracted. Complementary DNA (cDNA) was synthesized and quantitative real-time polymerase chain reaction (qPCR) was performed to evaluate the gene expression of IDH2, TET2 and KDM2B.

Results

A modulation in gene expression was observed before and after treatment with classic chemotherapeutic agents. It was possible to demonstrate a difference in gene expression when cells were treated with chemotherapeutic agents or decitabine alone when compared to chemotherapeutic agents in association with decitabine.

Conclusions

The genes tested, and the modulation of their expression during in vitro treatments suggest that IDH2, TET2, and KDM2B should be further investigated as potential biomarkers for ongoing treatment response and follow-up for patients diagnosed with hematological malignancies of the myeloid lineage.