HDAC inhibitors: Targets for tumor therapy, immune modulation and lung diseases

• HDACs are dysregulated in various malignancies and in some inflammatory lung diseases. • HDAC inhibitors are emerging as a successful epigenetic therapy by exploiting pathophysiology of tumor microenvironment. • HDAC inhibitors can activate multiple antitumor pathway which results in the destruction of transformed cells. • Nanocarrier-based HDACi delivery is a huge step forward in improving the targeted delivery of HDAC inhibitors. Histone deacetylases (HDACs) are enzymes that play a key role in the epigenetic regulation of gene expression by remodeling chromatin. Inhibition of HDACs is a prospective therapeutic approach for reversing epigenetic alteration in several diseases. In preclinical research, numerous types of HDAC inhibitors were discovered to exhibit powerful and selective anticancer properties. However, such research has revealed that the effects of HDAC inhibitors may be far broader and more intricate than previously thought. This review will provide insight into the HDAC inhibitors and their mechanism of action with special emphasis on the significance of HDAC inhibitors in the treatment of Chronic Obstructive Pulmonary Disease and lung cancer. Nanocarrier-mediated HDAC inhibitor delivery and new approaches for targeting HDACs are also discussed.