Whole genome methylation sequencing reveals epigenetic landscape and abnormal expression of FABP5 in extramammary Paget's disease.

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare cutaneous malignant tumor with a high recurrence rate after surgery. However, the genetic and epigenetic alterations underlying its pathogenesis remain unknown. DNA methylation is an important epigenetic modification involved in many biological processes. METHODS: In this study, enzymatic methyl-sequencing (EM-seq) technique was used to investigate the landscape of genome-wide DNA methylation from three pairs of tumor tissues and adjacent tissues of patients with EMPD. Additionally, we conducted histopathological examinations to assess the expression of fatty acid-binding protein 5 (FABP5) in another three paired samples from EMPD patients. RESULTS: The cluster analysis showed the good quality of the samples. A differential methylation region (DMR) heat map was used to quantitatively characterize genome-wide methylation differences between tumors and controls. Global DNA methylation level is lower in EMPD tissue compared to matched controls, indicating that DNA methylation discriminates between tumor and normal skin. And the top hypomethylation gene on the promoter region in tumor tissues was FABP5 on chromosome 8 with 38.44% decreased median methylation. We next identified the expression of FABP5 in paired tumors and adjacent tissues in three additional patients with EMPD. Immunofluorescence results showed FABP5 highly expressed in tumor tissues and co-located with CK7, CK20 and EMA. GO and KEGG enrichment analysis showed DMR genes on promoter are mainly enriched in the calcium ion transport, GTPase mediated signal transduction, Rap1 signaling pathway and GnRH signaling pathway. CONCLUSION: Taken together, our findings provide the first description of the whole genome methylation map of EMPD and identify FABP5 as a pathogenic target of EMPD.

Enhanced Expression of ARK5 in Hepatic Stellate Cell and Hepatocyte Synergistically Promote Liver Fibrosis.

AMPK-related protein kinase 5 (ARK5) is involved in a broad spectrum of physiological and cell events, and aberrant expression of ARK5 has been observed in a wide variety of solid tumors, including liver cancer. However, the role of ARK5 in liver fibrosis remains largely unexplored. We found that ARK5 expression was elevated in mouse fibrotic livers, and showed a positive correlation with the progression of liver fibrosis. ARK5 was highly expressed not only in activated hepatic stellate cells (HSCs), but also in hepatocytes. In HSCs, ARK5 prevents the degradation of transforming growth factor ß type I receptor (TßRI) and mothers against decapentaplegic homolog 4 (Smad4) proteins by inhibiting the expression of Smad ubiquitin regulatory factor 2 (Smurf2), thus maintaining the continuous transduction of the transforming growth factor ß (TGF-ß) signaling pathway, which is essential for cell activation, proliferation and survival. In hepatocytes, ARK5 induces the occurrence of epithelial-mesenchymal transition (EMT), and also promotes the secretion of inflammatory factors. Inflammatory factors, in turn, further enhance the activation of HSCs and deepen the degree of liver fibrosis. Notably, we demonstrated in a mouse model that targeting ARK5 with the selective inhibitor HTH-01-015 attenuates CCl4-induced liver fibrosis in mice. Taken together, the results indicate that ARK5 is a critical driver of liver fibrosis, and promotes liver fibrosis by synergy between HSCs and hepatocytes.

Inhibition of PARP activity improves therapeutic effect of ARPE-19 transplantation in RCS rats through decreasing photoreceptor death.

Photoreceptor (PR) dysfunction or death is the key pathological change in retinal degeneration (RD). The death of PRs might be due to a primary change in PRs themselves or secondary to the dysfunction of the retinal pigment epithelium (RPE). Poly(ADP-ribose) polymerase (PARP) was reported to be involved in primary PR death, but whether it plays a role in PR death secondary to RPE dysfunction has not been determined. To clarify this question and develop a new therapeutic approach, we studied the changes in PAR/PARP in the RCS rat, a RD model, and tested the effect of PARP intervention when given alone or in combination with RPE cell transplantation. The results showed that poly(ADP-ribosyl)ation of proteins was increased in PRs undergoing secondary death in RCS rats, and this result was confirmed by the observation of similar changes in sodium iodate (SI)-induced secondary RD in SD rats. The increase in PAR/PARP was highly associated with increased apoptotic PRs and decreased visual function, as represented by lowered b-wave amplitudes on electroretinogram (ERG). Then, as we expected, when the RCS rats were treated with subretinal injection of the PARP inhibitor PJ34, the RD process was delayed. Furthermore, when PJ34 was given simultaneously with subretinal ARPE-19 cell transplantation, the therapeutic effects were significantly improved and lasted longer than those of ARPE-19 or PJ34 treatment alone. These results provide a potential new approach for treating RD.

Echinatin suppresses cutaneous squamous cell carcinoma by targeting GSTM3-mediated ferroptosis.

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is one of the most common skin cancers for which effective drugs are urgently needed. Echinatin, a natural compound extracted from Glycyrrhiza plants, has shown promising antitumour effects. However, the efficacy and the direct target of echinatin in cSCC remain unclear. PURPOSE: This study conducted a systematic investigation of the antitumour effects of echinatin on cSCC and the underlying mechanisms involved. STUDY DESIGN AND METHODS: Three cSCC cell lines, a xenograft model, and a UV-induced cSCC mouse model were used to investigate the potential protective effects of echinatin. The interactions between echinatin and glutathione S-transferase mu3 (GSTM3) and between echinatin and peroxiredoxin-2 (PRDX2) were evaluated by a proteome microarray assay, pull-down LC‒MS/MS analysis, surface plasmon resonance, and molecular docking. The potential mechanisms of GSTM3-mediated echinatin activity were analysed by using western blotting, lentivirus infection and small interfering RNA (siRNA) transfection. RESULTS: In this study, we found that echinatin inhibited the proliferation and migration of cSCC cells but had no cytotoxic effect on primary human keratinocytes. Furthermore, echinatin significantly inhibited tumour growth in vivo. Mechanistically, our data showed that echinatin could directly bind to GSTM3 and PRDX2. Notably, echinatin inhibited GSTM3 and PRDX2 levels by promoting their proteasomal degradation, which led to the disruption of ROS production. We then revealed that echinatin increased mitochondrial ROS production by inhibiting GSTM3. Moreover, echinatin triggered ferroptosis by inhibiting GSTM3-mediated ferroptosis negative regulation (FNR) proteins. In addition, echinatin regulated GSTM3-mediated ROS/MAPK signalling. CONCLUSION: Echinatin has good antitumour effects both in vitro and in vivo. Moreover, our findings indicate that GSTM3 and PRDX2 could function as viable targets of echinatin in cSCC. Consequently, echinatin represents a novel treatment for cSCC through the targeting of GSTM3-mediated ferroptosis.

Multiple gouty tophi in the head and neck with normal serum uric acid: A case report and review of literatures.

BACKGROUND: Gouty tophus is rarely reported in the head and neck areas. To the best of our knowledge, this is the first report on multiple gouty tophi in the head and neck with normal serum uric acid (SUA) levels. CASE SUMMARY: We report a case of multiple gouty tophi in the nasal dorsal and auricle regions with normal SUA levels. The patient was admitted to the hospital with a chief complaint of recurrent nasal swelling and pain for 3 years, which was aggravated for 3 d. The patient's SUA level had been regularly reviewed in the outpatient department and had been successfully controlled for several years. Resection of the nasal masses was performed. Cartilage from the right ear cavity was used to repair the nasal defects. The pathological report confirmed a nasal gouty tophus. No recurrence or deformity was found after a 1 year follow-up. CONCLUSION: Normal SUA cannot completely negate the diagnosis of gouty tophus, especially in some rare regions.

Remodeling Lymphatic Vessels in Intrinsically Aged Skin on SKH-1 Mouse Using Low Dose 5-aminolevulinic Acid Photodynamic Therapy via VEGF-C/VEGFR3 Pathway.

BACKGROUND: Decline of lymphatic vessel (LV) density and function in intrinsically aged skin can lead to harmful substance accumulation and fluid imbalance. Whether it will be improved by low dose ALA-PDT needs to be investigated. AIMS: To investigate the effect of low dose ALA-PDT on remodeling LVs in intrinsically aged skin. METHODS: Low dose ALA-PDT with 3 sessions were applied on the dorsal skin of intrinsically aged SKH-1 mice (15 months old). Skin biopsies were obtained from young mice (4 months old, Young-control), intrinsically aged mice before PDT (Old-pre-PDT), and after PDT at different time points (Old-PDT-24h, Old-PDT-1w, Old-PDT-4w), and skin phenotypes were evaluated by dermoscopy. The structure of LVs and extracellular matrix were evaluated via immunofluorescence staining and HE. The drainage function of LVs was evaluated by Evans Blue assay in vivo. The expression of Calcium-binding EGF domain-containing protein 1 (CCBE1), VE-cadherin, and the activation of VEGF-C/VEGFR3 signaling pathway were evaluated by ELISA and Western Blot. RESULTS: The density of LVs decreased and the lymphatic clearance was significantly delayed in aged skin. Low dose ALA-PDT increased the density of LVs and blood vessels. The clearance of Evans Blue assay showed the drainage function of LVs was improved after PDT treatments in vivo. The VE-cadherin and VEGF-C/VEGFR3 pathway up-regulated in intrinsically aged skin after ALA-PDT treatments. CONCLUSIONS: LVs in intrinsically aged skin were remodeled and their function were restored by low dose ALA-PDT via up-regulating the VEGF-C/VEGFR3 pathway and stimulating the expression of VE-cadherin.

A dose-dependent protective effect of n-3 PUFAs in photoaging by promoting collagen production through MAPK pathway in SKH-1 mouse model.

BACKGROUND: Dietary supplementation of n-3 polyunsaturated fatty acids (n-3 PUFAs) can inhibit inflammation and oxidation of photoaging, but the effect and mechanism on regulation of dermis collagen remains poorly elucidated. The destruction of dermal collagen plays a crucial role in the process of long-term ultraviolet radiation (UVR) induced-photoaging, especially leading to deterioration of skin appearance and function. METHODS: In this study, we explored the protective effect of n-3 PUFAs on the regulation of collagen through the MAPK pathway using the SKH-1 photoaging mouse model. RESULTS: The results showed that n-3 PUFAs promoted collagen synthesis and reduced collagen degradation in a dose-dependent manner, which was mediated by the down-regulation of the MAPK pathway. In addition, n-3 PUFAs supplementation inhibited the production of MMP-1 and the UV-induced abnormal proliferation of keratinocytes. All these effects resulted in the remodeling of extracellular matrix (ECM) and finally made a significant improvement in the appearance of skin. CONCLUSION: Overall, the present study suggested that dietary supplementation of n-3 PUFAs has the potential clinical prospect to prevent UV-induced skin damage and photoaging.