SFRP5 inhibits the migration and invasion of melanoma cells through Wnt signaling pathway

Effect of 30% Supramolecular Salicylic Acid Peel on Skin Microbiota and Inflammation in Patients with Moderate-to-Severe Acne Vulgaris

INTRODUCTION

Thirty-percent supramolecular salicylic acid (SSA), a modified salicylic acid preparation, is a safe and effective treatment for moderate-to-severe acne vulgaris (AV). However, its mechanism of action remains unclear. We aimed to analyze the role of 30% SSA peels on skin microbiota and inflammation in patients with moderate-to-severe AV.

METHODS

A total of 28 patients were enrolled and received 30% SSA peels biweekly for 2 months. The Global Acne Grading System (GAGS) score, skin water content, transepidermal water loss (TEWL), pH, and sebum levels were assessed. Skin microbial samples and perilesional skin biopsies were obtained at the onset and 2 weeks after treatment completion. Samples were characterized using a high-throughput sequencing approach targeting a portion of the bacterial 16S ribosomal RNA gene.

RESULTS

After treatment, patients showed a significant improvement in their GAGS score and skin barrier indicators (P < 0.05). The GAGS score was positively associated with both the sebum concentration (R = 0.3, P = 0.027) and pH (R = 0.39, P = 0.003). Increased expression of caveolin-1 and decreased expression of interleukin (IL)-1a, IL-6, IL-17, transforming growth factor beta, and toll-like receptor 2 were observed in the skin tissue after treatment. The richness and evenness of the cutaneous microbiome decreased after treatment and the Staphylococcus proportion decreased significantly (P < 0.05), whereas the Propionibacterium proportion tended to decrease (P = 0.066).

CONCLUSIONS

On the basis of analyses of the skin barrier and microbiota, we speculate that the 30% SSA peel may have a therapeutic effect in patients with moderate-to-severe AV by improving the skin microenvironment and modulating the skin microbiome, thus reducing local inflammation.

6-Bromoindirubin-3′-Oxime Regulates Colony Formation, Apoptosis, and Odonto/Osteogenic Differentiation in Human Dental Pulp Stem Cells

6-bromoindirubin-3′-oxime (BIO) is a candidate small molecule that effectively modulates Wnt signalling owing to its stable property. The present study investigated the influence of BIO on the odonto/osteogenic differentiation of human dental pulp stem cells (hDPSCs). hDPSCs were treated with 200, 400, or 800 nM BIO, and the effects on hDPSC responses and osteogenic differentiation were assessed. BIO-mediated Wnt activation was confirmed by β-catenin nuclear translocation detected by immunofluorescence staining. BIO attenuated colony formation and cell migration determined by in vitro wound-healing assay. BIO increased early apoptotic cell population evaluated using flow cytometry. For osteogenic induction, BIO promoted alkaline phosphatase (ALP) activity and mineralisation in a dose-dependent manner. ALP, RUNX2, OCN, OSX, ANKH, DMP1, and DSPP mRNA expression were significantly upregulated. The OPG/RANKL expression ratio was also increased. Further, BIO attenuated adipogenic differentiation as demonstrated by decreased lipid accumulation and adipogenic-related gene expression. Bioinformatic analysis of RNA sequencing data from the BIO-treated hDPSCs revealed that BIO modulated pathways related to autophagy and actin cytoskeleton regulation. These findings demonstrated that BIO treatment promoted hDPSC osteogenic differentiation. Therefore, this small molecule is a strong candidate as a bioactive molecule to enhance dentin repair.

Hey1 promotes migration and invasion of melanoma cells via GRB2/PI3K/AKT signaling cascade

Increasing evidence indicates that Notch signaling regulates multiple intracellular biological processes in malignant melanoma. Whereas how Notch signaling is transduced to influence melanoma cell behaviors remains largely elusive. Here we show that the Notch signaling downstream target Hey1 promotes migration and invasion of melanoma cells via the GRB2/PI3K/AKT pathway. First, bioinformatics tools, immunohistochemistry, and Western blotting analysis showed that the expression of Hey1 is increased in melanoma. Then, both in vivo and in vitro experiments showed that Hey1 promotes the malignant behaviour of the melanoma cells. High-throughput RNA-sequencing analysis revealed that inhibition of Hey1 results in decreased GRB2 expression in melanoma cells. Last, functional experiments confirmed that Hey1 positively regulates GRB2/PI3K/AKT pathway to influence migration and invasion of melanoma cells. In summary, our results suggest that Hey1 promotes the invasion and metastasis of melanoma cells by regulating GRB2/PI3K/AKT pathway. Our study provides potential therapeutics in tumor biology.

SFRP5 inhibits melanin synthesis of melanocytes in vitiligo by suppressing the Wnt/β-catenin signaling

Secreted frizzled-related protein 5 (SFRP5) plays a pivotal role in regulating the development of many tissues and organs, however, as an inhibitor of Wnt signaling, the role of SFRP5 in vitiligo remains unknown. Hence, we speculated that SFRP5 might be associated with melanogenesis in melanocytes by regulating Wnt signaling in vitiligo. In this study, we found that SFRP5 was overexpressed in the skin lesions of patients with vitiligo. Compared with that in normal epidermal melanocytes (PIG1), the expression of SFRP5 was increased in vitiligo melanocytes (PIG3V). To investigate the effect of SFRP5 on melanin synthesis, PIG1 cells were infected with recombinant SFRP5 adenovirus (AdSFRP5), and PIG3V cells were infected with recombinant siSFRP5 adenovirus (AdsiSFRP5). The results showed that SFRP5 overexpression inhibited melanin synthesis in PIG1 cells through downregulation of microphthalmia-associated transcription factor (MITF) and its target proteins via suppression of the Wnt/β-catenin signaling pathway. Accordingly, SFRP5 silencing increased melanin synthesis and activated the Wnt signaling pathway in PIG3V cells. Moreover, SFRP5 overexpression also downregulated the transcriptional activity of T cell factor/lymphoid enhancer factor (TCF/LEF) in PIG1 cells. Furthermore, this inhibitory effect of SFRP5 on melanin synthesis was reversed by treatment with the β-catenin agonist, SKL2001. The inhibitory action of SFRP5 in pigmentation was further confirmed in vivo using a nude mouse model. Hence, our results indicate that SFRP5 can inhibit melanogenesis in melanocytes. Additionally, our findings showed that SFRP5 plays a vital role in the development of vitiligo, and thus may serve as a potential therapeutic target for vitiligo.