Ring size changes in the development of class I HDAC inhibitors

Area of Science:

• Medicinal Chemistry
• Molecular Biology
• Cancer Research

Background:

• Histone deacetylases (HDACs) are crucial epigenetic regulators implicated in various cancers.
• Class I HDACs, including HDAC1 and HDAC2, are attractive therapeutic targets.
• Developing selective inhibitors is essential to minimize off-target effects.

Purpose of the Study:

• To synthesize and characterize novel thienylbenzamide derivatives.
• To evaluate their inhibitory activity against Class I HDACs.
• To assess their efficacy in cancer cell lines and elucidate their mechanism of action.

Main Methods:

• Multi-step organic synthesis to generate fourteen thienylbenzamide compounds (7-20).
• In vitro assays to determine HDAC1 and HDAC2 inhibition selectivity.
• Cell-based assays using DLD1 and HCT116 cell lines to evaluate cytotoxicity.
• Apoptosis pathway analysis for mechanistic studies.

Main Results:

• Fourteen thienylbenzamides were successfully synthesized, revealing structure-activity relationships for Class I HDAC inhibition.
• All compounds demonstrated selective inhibition of HDAC1 and HDAC2 over other isoforms.
• Several compounds exhibited superior efficacy against DLD1 and HCT116 cells compared to a parent compound.
• Compounds 8 and 16 were found to induce HCT116 cell death via apoptosis activation.

Conclusions:

• Thienylbenzamides represent a promising scaffold for developing selective Class I HDAC inhibitors.
• Compounds 8 and 16 show potential as anticancer agents due to their ability to trigger apoptosis.
• Further investigation into these compounds could lead to novel therapeutic strategies for HDAC-related malignancies.