DNA damage triggers diverse cancers, particularly hepatocellular carcinoma (HCC), but the intrinsic link between DNA damage and tumorigenesis remains unclear. Due to its role as an epigenetic and transcriptional regulator, histone deacetylase 3 (HDAC3) is essential for DNA damage control and is often aberrantly expressed in human HCC. In this study, we used individual class I HDAC member-deficient mice to demonstrate that K9 in histone H3 (H3K9), which is the critical site for the assembly of DNA damage response complexes, is exclusively targeted by HDAC3. Ablation of HDAC3 disrupted the deacetylation and consequent trimethylation of H3K9 (H3K9me3), the first step in double-strand break (DSB) repair, and led to the accumulation of damaged DNA. Simultaneously, hyperacetylated H3K9 (H3K9ac) served as a transcriptional activator and enhanced multiple signaling pathways to promote tumorigenesis. Together these results show that HDAC3 targets the H3K9ac/H3K9me3 transition to serve as a critical regulator that controls both DNA damage repair and the transcription of many tumor-related genes. Moreover, these findings provide novel insights into the link between DNA damage and transcriptional reprogramming in tumorigenesis.

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In this study, we show a more efficient method for isolation and cultivation of dermal papilla cells from hair follicles of human scalp skin. The dermal partments of low hair follicles were pulled out from cutaneous fat and the bulb epithelium was teased out from the fibrous sheath with attached dermal papilla by applying gentle pressure with the tip of an occal forceps. When these fibrous sheaths were entirely digested into isolated cells by collagenase D but the dermal papillae were justly to be digested, collagenase D was discarded and the dermal papillae were isolated completely out from the resuspension solution by repeated low-speed centrifugation and transferred to another dish for free-floating culture. This procedure markedly simplifies the steps of isolated dermal papilla operation and relieves the laborious tension. Furthermore, dermal papillae could be isolated on a large-scale and remained intact. After collagenase digestion, the dermal papillae showed very high adherent rate and quicker growth than that of microdissection, which suggests that the definition factor of dermal papilla cell migration was relaxed and some structure had been activated or exposed. The cells exhibited a multi-layer forming property and spread-out growth style. They showed positive with alcian blue, with toluidine blue O for different gradient pH and PAS, which was similar to the staining results of in situ dermal papilla. It suggests that the culture papilla cells still synthesize and excrete neutral and acid mucopolysaccharides. Our results demonstrate that the papilla cells in culture condition still remain the ability to synthesize the specific extracellular matrix components of in situ dermal papilla, which supports the concept that the dermal papilla cell, a highly specialized fibroblast, especially is involved in hair growth regulation.

PDT, utilizing the topical application of 10% ALA, has a good result and excellent cosmetic effects for the treatment of verruca planae.

Melanoma is the most aggressive malignant skin tumor and arises from melanocytes. The resistance of melanoma cells to various treatments results in rapid tumor growth and high mortality. As a local therapeutic modality, photodynamic therapy has been successfully applied for clinical treatment of skin diseases. Photodynamic therapy is a relatively new treatment method for various types of malignant tumors in humans and, compared to conventional treatment methods, has fewer side effects, and is more accurate and non-invasive. Although several in vivo and in vitro studies have shown encouraging results regarding the potential benefits of photodynamic therapy as an adjuvant treatment for melanoma, its clinical application remains limited owing to its relative inefficiency. This review article discusses the use of photodynamic therapy in melanoma treatment as well as the latest progress made in deciphering the mechanism of tolerance. Lastly, potential targets are identified that may improve photodynamic therapy against melanoma cells.