A regulative epigenetic circuit supervised by HDAC7 represses IGFBP6 and IGFBP7 expression to sustain mammary stemness

Immunolocalization patterns of histone-deacetylases in salivary glands of mice during postnatal development

OBJECTIVE

Histone-deacetylases (HDACs) are epigenetic modulators involved in the control of gene expression. No data are available on the expression or subcellular localization of HDACs in salivary glands. The present study aims to examine the subcellular distribution of HDACs in salivary glands during postnatal development.

DESIGN

The major salivary glands of C57/BL6 mice were separately removed at 10, 25, 30,60 and 90 days after birth. Hematoxylin-eosin (H&E) and immunohistochemical staining were performed for HDACs. Gene Expression of HDACs in C57BL/6. NOD-Aec1Aec2 mice salivary glands during the development of Sjögren's syndrome-like illness were also analyzed by using the gene expression datasets (GSE 15640).

RESULTS

In the mice salivary gland, HDACs were found to have different localization patterns at various stages of development (10, 25, 30, 60, and 90 days). Apart from HDAC6, ductal cells of salivary glands were the primary sites for HDAC localization. HDAC2, 8, 5, 10 and 11 were expressed at high levels in the salivary gland after birth while HDAC6 showed no expression during postnatal development. This suggests that these HDAC subtypes may have different roles in salivary gland function. In the context of Sjögren's syndrome-like illness, HDAC 2, 8 and 10 showed low expression while HDAC1, 6,5,3 and 11 had relatively high expression in the salivary gland.

CONCLUSIONS

This study has provided an important reference for understanding the spatiotemporal-specific expression of HDACs in the salivary gland. These results offer new clues for the experimenters and hold promise for developing innovative therapeutic strategies for salivary gland-related diseases.

The landscape of histone modifications in epigenomics since 2020

Histone proteins are a primary component of chromatin; therefore, any modifications to their structure are anticipated to affect the behavior of our genetic material, which is manifested in the form of phenotypic changes at a molecular, cellular or organic level. The majority of histone modifications are of either methylation or acetylation type that regulate gene expression. Though, not all of these modifications are concerned with the direct regulation of gene transcription. Throughout its 13-year run, Epigenomics has never ceased to cover these most gripping epigenetic stories, a significant proportion of which is in the matter of histones and their modifications. As such, the current perspective piece is intended to highlight original histone-oriented contributions published in Epigenomics since 2020.

HDACs and the epigenetic plasticity of cancer cells: Target the complexity

Cancer cells must adapt to the hostile conditions of the microenvironment in terms of nutrition, space, and immune system attack. Mutations of DNA are the drivers of the tumorigenic process, but mutations must be able to hijack cellular functions to sustain the spread of mutant genomes. Transcriptional control is a key function in this context and is controlled by the rearrangement of the epigenome. Unlike genomic mutations, the epigenome of cancer cells can in principle be reversed. The discovery of the first epigenetic drugs triggered a contaminating enthusiasm. Unfortunately, the complexity of the epigenetic machinery has frustrated this enthusiasm. To develop efficient patient-oriented epigenetic therapies, we need to better understand the nature of this complexity. In this review, we will discuss recent advances in understanding the contribution of HDACs to the maintenance of the transformed state and the rational for their selective targeting.