Psoriasis is a common inflammatory systemic disease characterized by pro-inflammatory macrophages activation (M1 macrophage) infiltrated in the dermal layer. How M1 macrophage contributes to psoriasis remains unknown. In this study, we found that adenosine A2A receptor (A2AR) agonist CGS 21680 HCl alleviated the imiquimod (IMQ) and mouse IL-23 Protein (rmIL-23)-induced psoriasis inflammation through reducing infiltration of M1. Conversely, Adora2a deletion in mice exacerbated psoriasis-like phenotype. Mechanistically, A2AR activation inhibited M1 macrophage activation via the NF-κB-KRT16 pathway to reduce the secretion of CXCL10/11 and inhibit Th1/17 differentiation. Notably, the KRT16 expression was first found in M1 macrophage in our study, not only in keratinocytes (KCs). CXCL10/11 are first identified as primarily derived from macrophages and dendritic cells (DCs) rather than KCs in psoriasis using single cell RNA sequencing (scRNA-Seq). In total, the study emphasizes the importance of M1 as an innate immune cell in pathogenesis of psoriasis.

This study underscores the significance of identifying the clinical manifestations of pachyonychia congenita (PC) and emphasizes the patterns of genetic inheritance. A 12-month-old boy presented with a \"white hairy tongue\" and, following a comprehensive evaluation, was diagnosed with PC. His father exhibited similar symptoms. Genetic testing revealed a KRT16 pathogenic variant (c.616 T > G) in both the patient and his father, marking it as a novel variant in the PC literature. This case contributes to a broader understanding of PC\'s genetic diversity and its clinical presentations.

Lung cancer is the most diagnosed malignant cancer and the leading cause of cancer-related deaths worldwide, with advanced stage and metastasis being a major issue. The mechanism leading to metastasis is not yet understood. Here, we found that KRT16 is upregulated in metastatic lung cancer tissues and correlated with poor overall survival. Knockdown of KRT16 inhibits metastasis of lung cancer both in vitro and in vivo. Mechanistically, KRT16 interacts with vimentin, and depletion of KRT16 leads to downregulation of vimentin. KRT16 acquired its oncogenic ability by stabilizing vimentin, and vimentin is required for KRT16-driven metastasis. FBXO21 mediates the polyubiquitination and degradation of KRT16, and vimentin inhibits KRT16 ubiquitination and degradation by impairing its interaction with FBXO21. Significantly, IL-15 inhibits metastasis of lung cancer in a mouse model through upregulation of FBXO21, and the level of IL-15 in circulating serum was significantly higher in nonmetastatic lung cancer patients than in metastatic patients. Our findings indicate that targeting the FBXO21/KRT16/vimentin axis may benefit lung cancer patients with metastasis.

OBJECTIVE: Corneal repair is critical for the treatment and recovery of corneal injuries. However, the molecular mechanism underlying corneal repair remains unclear.
METHODS: A tree shrew model of corneal fungal infection was established by injecting Fusarium solani into the corneal stroma to study the role of miR-204-3p in repairing corneal injury induced by fungal keratitis and to explore the potential mechanisms underlying the repair process.
RESULTS: miR-204-3p expression was significantly downregulated, while KRT16 expression was significantly upregulated after F. solani infection in the cornea of tree shrews. Moreover, miR-204-3p injection promoted corneal injury repair post-infection, potentially by downregulating KRT16 expression. Results of a luciferase reporter gene assay showed that miR-204-3p had a targeted relationship with KRT16. KRT16 protein expression levels decreased after miR-204-3p injection into the cornea with fungal keratitis, reducing the degree of corneal injury.
CONCLUSIONS: In this study, we report for the first time that miR-204-3p and KRT16 influence the repair of corneal injury. In addition, their effects on the repair of corneal injury were studied in a tree shrew model, providing an experimental basis for the study of pathogenesis of human fungal keratitis.

Nasopharyngeal carcinoma (NPC) refers to a malignancy initiating from the superior mucosal epithelium of the nasopharynx. Optimal therapies for NPC are still needed. In this investigation, we attempted to explore whether BarH-like homeobox 2 (BARX2), a well-known tumor suppressor, had anti-cancer properties on NPC, and the possible mechanisms. After searching for NPC-related databases, we determined BARX2 as one of the core genes in NPC. The results of RT-qPCR and immunohistochemistry or Western blot demonstrated that BARX2 was reduced in NPC patients and cells. Ectopic expression of BARX2 reverted the malignant phenotype of NPC cells. Mechanistically, BARX2 bound to the keratin 16 (KRT16) promoter to downregulate its expression. In addition, BARX2 was found to reduce the phosphorylation levels of MEK and ERK. Further KRT16 upregulation in cells overexpressing BARX2 promoted malignant aggressiveness of C666-1 and HNE3 cells and activated the Ras signaling pathway. BARX2 inhibited the growth and metastasis of tumors and suppressed the Ras signaling pathway in vivo. In conclusion, our findings indicate that BARX2 reverts malignant phenotypes of NPC cells by downregulating KRT16 in a Ras-dependent fashion. BARX2 might act as a possible therapeutic regulator for NPC.

Objectives: keratin 16 (KRT16) is a type I cytokeratin that overexpressed in many kinds of cancers, but unlike other keratins, KRT16 was poorly studied, so the aim of current study was to determine the biological role of KRT16 in lung adenocarcinoma (LUAD). Materials and Methods: by utilizing open access data, we determined KRT16 expression in LUAD. After that we evaluated the biological role of KRT16 in-vitro and in-vivo. We also explored the reason for KRT16 overexpression. Last, we explored the clinical significance of KRT16 in LUAD. Results: we found KRT16 is overexpressed in LUAD and positively correlated with lymph node metastasis. Knockdown of KRT16 significantly influenced the LUAD cells\' migration, invasion, proliferation and epithelial-mesenchymal transition (EMT). Moreover, TFAP2A could transcriptionally overexpress KRT16, which contributed to the TFAP2A tumorigenicity. Last, we determined that high level of KRT16 predicts poor prognosis of LUAD patients. Conclusions: our data indicate that, TFAP2A induced KRT16 overexpression promotes tumorigenicity in LUAD via EMT, and KRT16 expression could serve as an independent prognosis marker.

Psoriasis is a multisystem disease affecting about 2% of the population, while keratin16 (KRT16) has been reported to participate in psoriasis. However, the specific mechanism of KRT16 in psoriasis was inadequately investigated. The objective of the study was to elucidate the mechanism by which siRNA-mediated silencing of KRT16 affects keratinocyte proliferation and vascular endothelial growth factor (VEGF) secretion in psoriasis through the extracellular signal-related kinase (ERK) signaling pathway. Psoriasis-related core gene KRT16 was screened out. Then, the expression of KRT16, VEGF, and ERK signaling pathway-related genes was detected in psoriatic patients. To further investigate the mechanism of KRT16, keratinocytes in psoriatic patients were treated with KRT16 siRNA or/and ERK inhibitor (PD98059) to detect the changes in related gene expression and cell survival. KRT16 was involved in psoriasis development. The expression levels of KRT16, p-ERK1/2, and VEGF in lesion tissues are significantly elevated. Keratinocytes treated with KRT16-siRNA and KRT16-siRNA + PD98059 exhibited reduced KRT16, p-ERK1/2, and VEGF expression. The cell survival rate in cells treated with KRT16-siRNA, PD98059, and KRT16-siRNA + PD98059 reduced significantly. These findings indicate that silencing KRT16 inhibits keratinocyte proliferation and VEGF secretion in psoriasis via inhibition of ERK signaling pathway, which provides a basic theory in the treatment of psoriasis.

Pachyonychia congenita is a rare, autosomal dominant genetic disease characterized by painful palmoplantar keratoderma and hypertrophic nail dystrophy. This disorder is caused by mutations in any one of five cytoskeletal keratin proteins, K6a, K6b, K6c, K16 and K17. Here, we describe a new p.Leu421Pro (c.1262T>C) mutation in the highly conserved helix termination motif of K16 in a large Spanish family. Bioinformatic analyses as well as previous descriptions in the literature of homologous mutations in other keratin-coding genes show that this mutation is probably causative of the disease.