DTL promotes head and neck squamous cell carcinoma progression by mediating the degradation of ARGLU1 to regulate the Notch signaling pathway.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide, with a high incidence in squamous epithelium. The E3 ubiquitin ligase DTL is a component of the CRL4A complex and is widely involved in tumor progression. We aimed to analyze the role of DTL in HNSCC and to explore its mechanism of action. Through clinical analysis, we found that DTL is upregulated in HNSCC tissues and is associated with the tumor microenvironment and poor survival in patients. Through gain-of-function and loss-of-function assays, we showed that DTL promotes cell proliferation and migration in vitro and tumor growth in vivo. Mass spectrometry analysis and immunoprecipitation assays showed that DTL interacts with ARGLU1 to promote K11-linked ubiquitination-mediated degradation of ARGLU1, thereby promoting the activation of the CSL-dependent Notch signaling pathway. Furthermore, siARGLU1 blocks the inhibitory effects of DTL knockdown on HNSCC cells. In this study, we showed that DTL promotes HNSCC progression through K11-linked ubiquitination of ARGLU1 to activate the CSL-dependent Notch pathway. These findings identify a promising therapeutic target for HNSCC.

Role of miRNAs in melanin metabolism: Implications in melanin-related diseases.

BACKGROUND: MicroRNAs (miRNAs) are short single-stranded non-coding RNAs that regulate degradation and expression of messenger RNA (mRNA) and play a wide range of key roles in different biological processes. They mediate different stages of melanocyte differentiation, growth, and apoptosis through a variety of pathways and can mediate melanin production by targeting key enzymes. AIMS: This article was aimed to review the role of miRNAs in melanin metabolism and to introduce the role and significance of miRNAs in melanin-related diseases. MATERIALS & METHODS: Systematic search and retrospective review were performed on the published data. RESULTS: This paper reviews the process of melanin synthesis and the regulatory mechanism, explores the miRNA expression profiles in different model organisms, and introduces the mechanisms of several key miRNAs participating in melanin metabolism through target genes. We also explore the potential role of miRNA as a new target for the treatment of melanin metabolism disease, including vitiligo, melanoma, and chloasma. CONCLUSION: miRNAs play a key role in melanin-related diseases, and the miRNAs involved may be potential therapeutic targets.

The Ubiquitin Proteasome System and Skin Fibrosis.

The ubiquitin proteasome system (UPS) is a highly conserved way to regulate protein turnover in cells. The UPS hydrolyzes and destroys variant or misfolded proteins and finely regulates proteins involved in differentiation, apoptosis, and other biological processes. This system is a key regulatory factor in the proliferation, differentiation, and collagen secretion of skin fibroblasts. E3 ubiquitin protein ligases Parkin and NEDD4 regulate multiple signaling pathways in keloid. Tumor necrosis factor (TNF) receptor-associated factor 4 (TRAF4) binding with deubiquitinase USP10 can induce p53 destabilization and promote keloid-derived fibroblast proliferation. The UPS participates in the occurrence and development of hypertrophic scars by regulating the transforming growth factor (TGF)-ß/Smad signaling pathway. An initial study suggests that TNFα-induced protein 3 (TNFAIP3) polymorphisms may be significantly associated with scleroderma susceptibility in individuals of Caucasian descent. Sumoylation and multiple ubiquitin ligases, including Smurfs, UFD2, and KLHL42, play vital roles in scleroderma by targeting the TGF-ß/Smad signaling pathway. In the future, drugs targeting E3 ligases and deubiquitinating enzymes have great potential for the treatment of skin fibrosis.

Transgelin-2 contributes to proliferation and progression of hepatocellular carcinoma via regulating Annexin A2.

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors, but its pathogenesis is not clear. This study found that the expression of TAGLN2 mRNA and protein in HCC was higher than that in adjacent tissues. TCGA database analysis further confirmed this result, and found that the expression of TAGLN2 was positively correlated with the prognosis of HCC, suggesting that TAGLN2 may be a tumor promoter gene. Then the TAGLN2-Annexin A2 (ANXA2) interaction and NF-κB signaling pathway were further clarified during the invasion and metastasis of HCC. This mechanism provides a theoretical basis for further finding molecular targets and drug targets related to HCC metastasis.

Integrated Interaction Network of MicroRNA Target Genes in Keloid Scarring.

Keloids are a common dermal pathological disorder characterized by the excessive deposition of extracellular matrix components; however, the exact pathogenesis of the disease is still not clear. Studies increasingly suggest that microRNAs (miRNAs) can play a key role in the process of keloid scarring. In this study, the valuable miRNAs and target genes were screened and the interaction network was constructed. We also predicted target genes of reported miRNAs using TargetScan and miRTarBase software. Cytoscape 3.0.1 further showed the interaction network of miRNA and target genes. Among the various miRNAs involved in keloid pathogenesis, miRNA-21, miRNA-141-3p, miRNA-181a, and miRNA-205 were thought to up-regulate the proliferation and decrease apoptosis of keloid-derived fibroblasts through the PI3K/Akt/mammalian target of rapamycin (mTOR) signaling pathway. miRNA-637 and miRNA-1224 inhibited keloid fibroblasts proliferation and promoted apoptosis via the transforming growth factor (TGF)-ß1/Smad3 signaling pathway. miRNA-21 was also involved in mitochondrial-mediated apoptosis and miRNA-31 targeted vascular endothelial growth factor (VEGF) signaling pathway. miRNA-199a may be one key factor in the cell cycle checkpoint signal pathway of keloid-derived fibroblasts. It was also found that miRNA-29a and miRNA-196a mediated collagen metabolism. These pivotal miRNAs and regulatory processes further improve the data on the epigenetic mechanisms of keloids and provide hope for the use of small molecules in the treatment of keloids.

Genome-wide identification of long non-coding RNA and mRNA profiling using RNA sequencing in subjects with sensitive skin.

Sensitive skin (SS) is a condition of subjective cutaneous hyper-reactivity. The role of long non-coding RNAs (lncRNAs) in subjects with SS is unclear. Therefore, the aim of the present study was to provide a comprehensive profile of the mRNAs and lncRNAs in subjects with SS. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis presented the characteristics of associated protein-coding genes. In addition, a co-expression network of lncRNA and mRNA was constructed to identify potential underlying regulation targets; the results were verified by quantitative real-time PCR (qRT-PCR) and RNA-seq analyses in patients with SS and normal samples. Compared with the normal skin group, 266 novel lncRNAs and 6750 annotated lncRNAs were identified in the SS group. A total of 71 lncRNA transcripts and 2615 mRNA transcripts were differentially expressed (P < 0.05). The heat signature of the SS samples could be distinguished from the normal skin samples, whereas the majority of the genes that were present in enriched pathways were those that participated in focal adhesion, PI3K-Akt signaling, and cancer-related pathways. Five transcripts were selected for qRT-PCR analysis and the results were consistent with RNA-seq. The results suggested that LNC_000265 may play a role in the epidermal barrier structure of patient with SS. The data suggest novel genes and pathways that may be involved in the pathogenesis of SS and highlight potential targets that could be used for individualized treatment applications.