Related Experiment Video
Updated: Mar 19, 2026
Proliferation and Differentiation of Murine Myeloid Precursor 32D/G-CSF-R Cells
Published on: February 21, 2018
miR-34b Targets HSF1 to Suppress Cell Survival in Acute Myeloid Leukemia
Gangcan Li1, Yanping Song, Yunjie Zhang
1Institute of Hematopathy, Xi'an Central Hospital, Xian, Shaanxi, China.
Abstract:
Acute myeloid leukemia (AML) is the most lethal hematological malignancy, and the occurrence of chemoresistance prevents the achievement of complete remission following the standard therapy. MicroRNAs have been extensively investigated as critical regulators of hematopoiesis and leukemogenesis, and they represent a promising strategy for AML therapy. In this study, we identified miR-34b as a novel regulator in myeloid proliferation and apoptosis of leukemic cells. We found that miR-34b was developmentally upregulated in plasma and myeloid cells of healthy subjects, while it was significantly reduced in blood samples of patients with AML and AML cell lines. Moreover, the miR-34b mimicked transfection-mediated restoration of miR-34b inhibited cell viability and promoted cell apoptosis of HL-60 and OCI-AML3 cell lines. Using a miRNA predicting algorithm miRanda, we selected a potent target heat shock transcription factor 1 (HSF1) since that is a master regulator of the heat shock response and is associated with cancer aggressiveness and dissemination. In contrast to the level of miR-34b, HSF1 was highly expressed in blood samples of patients with AML and AML cell lines. The luciferase reporter assay revealed that miR-34b directly targeted the HSF1 gene. HSF1 silencing exhibited comparable inhibitory effects on AML cell proliferation and survival. The upregulated HSF1 elevated the activation of the Wnt-β-catenin pathway. In conclusion, miR-34b suppressed AML cell proliferation and survival by targeting HSF1, in turn leading to the inactivation of Wnt-β-catenin pathway, which may highlight a new therapeutic approach for AML.
Insights
MicroRNA-34b suppresses acute myeloid leukemia (AML) by targeting heat shock transcription factor 1 (HSF1). Restoring miR-34b inhibits cancer cell growth and survival, offering a potential new AML therapy.
Area of Science:
- Hematology
- Molecular Biology
- Oncology
Background:
- Acute myeloid leukemia (AML) is a deadly blood cancer with significant chemoresistance.
- MicroRNAs are key regulators of blood cell development and cancer, showing therapeutic promise for AML.
- Current AML therapies face challenges due to chemoresistance, necessitating novel treatment strategies.
Purpose of the Study:
- To identify novel microRNAs regulating myeloid proliferation and apoptosis in AML.
- To investigate the role of miR-34b in AML pathogenesis and its therapeutic potential.
- To elucidate the molecular mechanisms underlying miR-34b's function in AML.
Main Methods:
- Analysis of miR-34b expression in healthy individuals and AML patients/cell lines.
- Transfection with miR-34b mimics to assess effects on leukemic cell viability and apoptosis.
- Bioinformatic prediction and experimental validation (luciferase assay) of miR-34b targets.
- Investigation of HSF1 and Wnt-β-catenin pathway involvement.
Main Results:
- miR-34b was downregulated in AML patients and cell lines, while HSF1 was upregulated.
- Restoring miR-34b inhibited AML cell proliferation and induced apoptosis.
- miR-34b directly targets and downregulates HSF1, a key regulator of cancer aggressiveness.
- HSF1 silencing mimicked miR-34b's inhibitory effects on AML cells.
- HSF1 upregulation activated the Wnt-β-catenin pathway.
Conclusions:
- miR-34b acts as a tumor suppressor in AML by targeting HSF1.
- The miR-34b/HSF1 axis regulates AML cell proliferation, survival, and apoptosis.
- Inhibition of the Wnt-β-catenin pathway by miR-34b contributes to its anti-leukemic effects.
- Targeting the miR-34b/HSF1 pathway presents a promising therapeutic strategy for AML.
