Inhibition of histone deacetylation: a strategy for tumor radiosensitization

Area of Science:

• Oncology
• Molecular Biology
• Radiotherapy

Background:

• Strategies to improve tumor radiosensitivity are focusing on molecular targets.
• Histone acetylation, regulated by histone acetylases and histone deacetylases (HDACs), influences chromatin structure and gene expression, impacting radioresponse.
• HDAC inhibitors are being developed to modify histone acetylation status.

Purpose of the Study:

• To investigate the role of histone deacetylase (HDAC) inhibitors in enhancing tumor radiosensitivity.
• To explore the potential of HDAC inhibitors in combination with radiotherapy.

Main Methods:

• Development of structurally diverse HDAC inhibitors.
• Evaluation of HDAC inhibitors' effects on histone acetylation and gene expression.
• Preclinical testing of HDAC inhibitors for antitumor activity and radiosensitizing effects in various human tumor cell lines.
• Analysis of early clinical trial data for HDAC inhibitors as monotherapy and in combination treatments.

Main Results:

• Second-generation HDAC inhibitors show improved bioavailability and pharmacological properties.
• While HDAC inhibitors demonstrate antitumor activity as single agents in preclinical models, clinical monotherapy shows limited efficacy (cytostasis).
• Preclinical studies indicate that HDAC inhibitors can significantly enhance both in vitro and in vivo radiosensitivity across a spectrum of solid tumors.

Conclusions:

• HDAC inhibitors represent a promising strategy for enhancing tumor radiosensitivity.
• HDAC inhibitors are under investigation in clinical trials, including combinations with chemotherapy and radiotherapy.
• Further research into HDAC inhibitors holds potential for improving radiotherapy outcomes in cancer treatment.