A BET inhibitor, NHWD-870, can downregulate dendritic cells maturation via the IRF7-mediated signaling pathway to ameliorate imiquimod-induced psoriasis-like murine skin inflammation.

Psoriasis is a chronic, recurrent, inflammatory dermatosis accompanied by excessive activation of dendritic cells (DCs), which are primarily responsible for initiating an immune response. The bromodomain and extraterminal domain (BET) family plays a pivotal role in the transcriptional regulation of inflammation and its inhibitors can downregulate DCs maturation and activation. Here we investigated the effect of NHWD-870, a potent BET inhibitor, on inflammation in an imiquimod (IMQ)-induced psoriasis-like mouse model and murine bone marrow-derived dendritic cells (BMDCs) stimulated by lipopolysaccharide (LPS) and IMQ. Application of NHWD-870 significantly ameliorated IMQ-triggered skin inflammation in mice, and markers associated with DC maturation (CD40, CD80 and CD86) were decreased in skin lesions, spleen and lymph nodes. Additionally, NHWD-870 reduced LPS or IMQ induced DCs maturation and activation in vitro, with lower expression of inflammatory cytokines [interleukin (IL)-12, IL-23, tumor necrosis factor-α, IL-6, IL-1ß, chemokine (C-X-C motif) ligand (CXCL)9 and CXCL10]. In addition, we found that interferon regulatory factor 7 (IRF7) significantly increased during DCs maturation, and inhibition of IRF7 could impair BMDCs maturation and activation. What's more, IRF7 was highly expressed in both psoriatic patients and IMQ-induced psoriasis-like mice. Single-cell RNA sequencing of normal and psoriatic skin demonstrated that IRF7 expression was increased in DCs of psoriatic skin. While NHWD-870 could inhibit IRF7 and phosphorylated-IRF7 expression in vivo and in vitro. These results indicate that NHWD-870 suppresses the maturation and activation of DCs by decreasing IRF7 proteins which finally alleviates psoriasis-like skin lesions, and NHWD-870 may be a potent therapeutic drug for psoriasis.

Single-Cell Profiling Reveals Sustained Immune Infiltration, Surveillance, and Tumor Heterogeneity in Infiltrative Basal Cell Carcinoma.

Infiltrative basal cell carcinoma (iBCC) is a particularly aggressive subtype of basal cell carcinoma that tends to progress and recur after surgery, and its malignancy is closely related to the tumor microenvironment. In this study, we performed a comprehensive single-cell RNA analysis to profile 29,334 cells from iBCC and adjacent normal skin. We found active immune collaborations enriched in iBCC. Specifically, SPP1+CXCL9/10high macrophage 1 had strong BAFF signaling with plasma cells, and T follicular helper-like cells highly expressed the B-cell chemokine CXCL13. Heterogeneous proinflammatory SPP1+CXCL9/10high macrophage 1 and angiogenesis-related SPP1+CCL2high macrophage 1 were identified within the tumor microenvironment. Interestingly, we found an upregulation of major histocompatibility complex I molecules in fibroblasts in iBCC compared with those in adjacent normal skin. Moreover, MDK signals derived from malignant basal cells were markedly increased, and their expression was an independent factor in predicting the infiltration depth of iBCC, emphasizing its role in driving malignancy and remodeling the tumor microenvironment. In addition, we identified differentiation-associated SOSTDC1+IGFBP5+CTSV+ malignant basal subtype 1 and epithelial-mesenchymal transition-associated TNC+SFRP1+CHGA+ malignant basal subtype 2 cells. The high expression of malignant basal 2 cell markers was associated with the invasion and recurrence of iBCC. Altogether, our study helps to elucidate the cellular heterogeneity in iBCC and provides potential therapeutic targets for clinical research.

Signatures of EMT, immunosuppression, and inflammation in primary and recurrent human cutaneous squamous cell carcinoma at single-cell resolution.

Rationale: The recurrence of cutaneous squamous cell carcinoma (cSCC) after surgery is associated with the reprogramming of the tumor microenvironment (TME), and remains a key factor affecting its outcomes. Methods: We employed single-cell RNA sequencing (scRNA-seq) to examine the dynamic changes in epithelial cells, T cells, myeloid cells, and fibroblasts between primary and recurrent cSCC. Cell clustering, cell trajectory, cell-cell communication, and gene set enrichment analysis were used to investigate the TME heterogeneity between primary and recurrent cSCC. Gene expression differences were monitored by IHC staining. Results: We examined the immunosuppressed microenvironment in recurrent cSCC, which exhibited a T cell-excluded and SPP1+ tumor-associated macrophages (TAMs)-enriched status. In recurrent cSCC, CD8+ T cells showed high exhaustion and low inflammatory features, while SPP1+ TAMs displayed global pro-tumor characteristics, including decreased phagocytosis and inflammation and increased angiogenesis. Furthermore, the subgroups of SPP1+ TAMs harbored distinct functions. SPP1+ CD209high TAMs showed features of phagocytosis, while SPP1+ CD209low TAMs tended to have a high angiogenic ability. A subpopulation of tumor-specific keratinocytes (TSKs) showed significant epithelial-mesenchymal transition (EMT) features in recurrent cSCC, probably due to their active communication with IL7R + cancer-associated fibroblasts (CAFs). Moreover, we found that the pleiotropic growth factor/cytokine Midkine (MDK) could provoke different cell-cell interactions in cSCC with distinctive staging. In primary cSCC, MDK was highly expressed in fibroblasts and could promote their proliferation and block the migration of tumor cells, while in recurrent cSCC, the high expression of MDK in TSKs promoted their proliferation and metastasis. Conclusion: Our study provides insights into the critical mechanisms of cSCC progression, which might facilitate the development of a powerful approach for the prevention and treatment of cSCC recurrence.

Evaluation of vertical transmission of SARS-CoV-2 in utero: Nine pregnant women and their newborns.

INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), mainly transmitted by droplets and close contact, has caused a pandemic worldwide as of March 2020. According to the current case reports and cohort studies, the symptoms of pregnant women infected with SARS-CoV-2 were similar to normal adults and may cause a series of adverse consequences of pregnancy (placental abruption, fetal distress, epilepsy during pregnancy, etc.). However, whether SARS-CoV-2 can be transmitted to the fetus through the placental barrier is still a focus of debate. METHODS: In this study, in order to find out whether SARS-CoV-2 can infect fetus through the placental barrier, we performed qualitative detection of virus structural protein (spike protein and nucleoprotein) and targeted receptor protein Angiotensin Converting Enzyme 2 (ACE2), Basigin (CD147) and molecular chaperone GRP78 expression on the placental tissue of seven pregnant women diagnosed with COVID-19 through immunohistochemistry. Amniotic fluid, neonatal throat, anal swab and breastmilk samples were collected immediately in the operating room or delivery room for verification after delivery, which were all tested for SARS-CoV-2 by reverse transcriptionpolymerase chain reaction (RT-PCR). RESULTS/DISCUSSION: The result showed that CD147 was expressed on the basal side of the chorionic trophoblast cell membrane and ACE2 was expressed on the maternal side, while GRP78 was strongly expressed in the cell membrane and cytoplasm. The RT-PCR results of Amniotic fluid, neonatal throat, anal swab and breastmilk samples were all negative. On the basis of these findings, we speculated that it may be due to the placental barrier between mother and baby, for example, villous matrix and interstitial blood vessels have low expression of virus-related receptors (ACE2, CD147, GRP78), the probability of vertical transmission of SARS-CoV-2 through the placenta is low.

Convalescent plasma to treat COVID-19: clinical experience and efficacy.

The recent outbreak of COVID-19 in the world is currently a big threat to global health and economy. Convalescent plasma has been confirmed effective against the novel corona virus in preliminary studies. In this paper, we first described the therapeutic schedule, antibody detection method, indications, contraindications of the convalescent plasmas and reported the effectiveness of convalescent plasma therapy by a retrospective cohort study.

Procalcitonin levels in COVID-19 patients.

Coronavirus disease 2019 (COVID-19), caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been declared a pandemic. This study analysed 95 SARS-CoV-2-infected patients, including 62 moderate COVID-19 patients, 21 severe COVID-19 patients and 12 critical COVID-19 patients (6 patients died, all critical). The results showed that the mean serum procalcitonin (PCT) levels were over four times higher in severe patients than in moderate patients and were over eight times higher in critical patients than in moderate patients. For discharged patients, both high-normal PCT levels and abnormal PCT levels decreased during recovery. However, in death cases, serum levels of PCT increased as the disease worsened. We demonstrate that PCT may be an indicator of disease severity in COVID-19 and may contribute to determining the severity of patients infected with SARS-CoV-2. Moreover, serial PCT measurements may be useful in predicting the prognosis.

Potent BRD4 inhibitor suppresses cancer cell-macrophage interaction.

Small molecule inhibitor of the bromodomain and extraterminal domain (BET) family proteins is a promising option for cancer treatment. However, current BET inhibitors are limited by their potency or oral bioavailability. Here we report the discovery and characterization of NHWD-870, a BET inhibitor that is more potent than three major clinical stage BET inhibitors BMS-986158, OTX-015, and GSK-525762. NHWD-870 causes tumor shrinkage or significantly suppresses tumor growth in nine xenograft or syngeneic models. In addition to its ability to downregulate c-MYC and directly inhibit tumor cell proliferation, NHWD-870 blocks the proliferation of tumor associated macrophages (TAMs) through multiple mechanisms, partly by reducing the expression and secretion of macrophage colony-stimulating factor CSF1 by tumor cells. NHWD-870 inhibits CSF1 expression through suppressing BRD4 and its target HIF1α. Taken together, these results reveal a mechanism by which BRD4 inhibition suppresses tumor growth, and support further development of NHWD-870 to treat solid tumors.

Roles of inflammation factors in melanogenesis (Review).

The occurrence of hyperpigmentation or hypopigmentation after inflammation is a common condition in dermatology and cosmetology. Since the exact mechanism of its occurrence is not yet known, prevention and treatment are troublesome. Previous studies have confirmed that α­melanocyte­stimulating hormone, stem cell factor and other factors can promote melanogenesis­related gene expression through the activation of signaling pathways. Recent studies have revealed that a variety of inflammatory mediators can also participate in the regulation of melanogenesis in melanocytes. In this review, we summarized that interleukin­18, interleukin­33, granulocyte­macrophage colony stimulating factor, interferon­Î³, prostaglandin E2 have the effect of promoting melanogenesis, while interleukin­1, interleukin­4, interleukin­6, interleukin­17 and tumor necrosis factor can inhibit melanogenesis. Further studies have found that these inflammatory factors may activate or inhibit melanogenesis­related signaling pathways (such as protein kinase A and mitogen activated protein kinase) by binding to corresponding receptors, thereby promoting or inhibiting the expression of melanogenesis­related genes and regulating skin pigmentation processes. This suggests that the development of drugs or treatment methods from the perspective of regulating inflammation can provide new ideas and new targets for the treatment of pigmented dermatosis. This review outlines the current understanding of the inflammation factors' roles in melanogenesis.

The Long Noncoding RNA UCA1 Negatively Regulates Melanogenesis in Melanocytes.

The long noncoding RNA UCA1 was first discovered in bladder cancer and is known to regulate the proliferation and migration of melanoma. However, its role in melanogenesis is unclear. In this study, we aimed to explore the role and mechanism of UCA1 in melanogenesis. Our findings showed that the expression of UCA1 was negatively correlated with melanin content in melanocytes and pigmented nevus. Overexpression of UCA1 in melanocytes decreased melanin content and the expression of melanogenesis-related genes, whereas knockdown of UCA1 in melanocytes had the opposite effect. High-throughput sequencing revealed that microphthalmia-associated transcription factor (MITF), an important transcription factor affecting melanogenesis, was also negatively correlated with the expression of UCA1. Furthermore, the transcription factor CRE-binding protein (CREB), which promotes MITF expression, was negatively regulated by UCA1. The cAMP/protein kinase A (PKA), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) signaling pathways, which are upstream of the CREB/MITF/melanogenesis axis, were activated or inhibited in response to silencing or enhancing UCA1 expression, respectively. In addition, enhanced UCA1 expression downregulates the expression of melanogenesis-related genes induced by UVB in melanocytes. In conclusion, UCA1 may negatively regulate the CREB/MITF/melanogenesis axis through inhibiting the cAMP/PKA, ERK, and JNK signaling pathways in melanocytes. UCA1 may be a potential therapeutic target for the treatment of pigmented skin diseases.

Ganoderma lucidum polysaccharide reduces melanogenesis by inhibiting the paracrine effects of keratinocytes and fibroblasts via IL-6/STAT3/FGF2 pathway.

Our previous study found that Ganoderma lucidum polysaccharide (GLP), bioactive ingredients from Ganoderma lucidum, protected fibroblasts from photoaging. However, whether GLP can affect melanogenesis in melanocytes through regulating paracrine mediators that secreted by keratinocytes and fibroblasts is unclear. We aimed to investigate the efficacy and mechanisms of action of GLP in melanogenesis by regulating paracrine effects of keratinocytes and fibroblasts. The effect of GLP on cell viability affected by GLP was measured by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. After an immortal keratinocyte line (HaCaT) and primary fibroblasts (FB) were treated with GLP, the supernatants of HaCaT and FB cells were collected and cocultured with an immortalized melanocyte line (PIG1). The expression levels of melanogenesis-associated genes in PIG1 cells were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis. Furthermore, FRS-2, ERK, JNK, and p38 phosphorylation levels were measured. Then, major melanogenic paracrine mediators in HaCaT and FB cells treated with GLP were evaluated by qRT-PCR and enzyme-linked immunosorbent assay (ELISA). In addition, the expression of IL-6 and STAT3 was examined in HaCaT and FB cells. GLP was not cytotoxic to HaCaT and FB cells. The supernatants of GLP-treated HaCaT and FB cells downregulated the expression levels of MITF, TYR, TYRP1, TYRP2, RAB27A, and FSCN1 genes and inhibited the phosphorylation of FRS-2, ERK, JNK, and p38 in PIG1 cells. GLP also decreased FGF2 secretion in HaCaT and FB cells. Moreover, GLP reduced IL-6 expression and STAT3 phosphorylation in HaCaT and FB cells. GLP reduced melanogenesis in melanocytes by inhibiting the paracrine effects of keratinocytes and fibroblasts via IL-6/STAT3/FGF2 pathway.

Downregulation of TUG1 promotes melanogenesis and UVB-induced melanogenesis.

Studies have revealed that taurine upregulated gene 1 (TUG1), an important member of the long non-coding RNA family, is involved in the regulation of cell growth, tumorigenesis and invasion, insulin secretion and so on. However, its role in melanogenesis has not been explored. This study attempts to explore the effects of TUG1 on melanogenesis and its regulatory mechanisms. We evaluated the expression changes in melanogenesis-related genes and detected phosphorylation levels of ERK, JNK and P38 in TUG1 downregulated melanocytes. After exposure of melanocytes to UVB irradiation, the expression of TUG1 and melanogenesis-related genes was detected. We found that the expression of tyrosinase (TYR), tyrosine-related protein 1 (TYRP1) and tyrosine-related protein 2 (TYRP2) was upregulated and that the phosphorylation level of ERK was downregulated by downregulating TUG1. Inhibition of TUG1 could further upregulate the expression of UVB-induced melanogenesis-related genes. In conclusion, TUG1 negatively regulates melanocyte melanogenesis via the ERK pathway and plays a negative role in UVB-induced melanogenesis.

Ganoderma lucidum polysaccharide inhibits UVB-induced melanogenesis by antagonizing cAMP/PKA and ROS/MAPK signaling pathways.

Ultraviolet (UV)-induced pigmentation is very common in clinical practice, but the current treatments are rarely effective, accompanied by some side effects. Ganoderma lucidum polysaccharide (GLP) is a natural antioxidant with no toxic side effects, which can antagonize UVB-induced fibroblast photo aging. The study aims to explore the role of GLP in inhibiting UVB-induced melanogenesis and its possible mechanism. The expression of melanogenesis genes such as microphthalmia-associated transcription factor (MITF), tyrosine (TYR), tyrosinase related protein 1 (TYRP1), tyrosinase related protein 2 (TYRP2), ras-related protein Rab-27A (Rab27A), and Myosin shows an upward trend after exposure of B16F10 and PIG1 cells to UVB irradiation, but GLP can downregulate the expression of genes related to UVB-induced melanogenesis. GLP can inhibit UVB-activated protein kinase A (PKA) and mitogen-activated protein kinase (MAPK) signaling pathways. Besides, GLP protects mitochondria from UVB damage and inhibits reactive oxygen species (ROS) production. Also, UVB-induced cyclic adenosine monophosphate (cAMP) can be inhibited. It has been found in the experiments of UVB-induced skin pigmentation in zebrafish that GLP is capable of inhibiting UVB-induced skin pigmentation. Meanwhile, it can greatly relieve erythema reaction in guinea pig skin caused by high-dosage UVB irradiation. In conclusion, this study shows that GLP can inhibit UVB-induced melanogenesis by antagonizing cAMP/PKA and ROS/MAPK signaling pathways and is a potential natural safe whitening sunscreen additive.

Functions and regulatory mechanisms of metastasis-associated lung adenocarcinoma transcript 1.

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a long noncoding RNA whose transcript is around 8 kb in length. As an important stress response molecule, MALAT1 can be expressed differently under stress conditions, such as hypoxia, high glucose, hydrogen peroxide, ultraviolet irradiation, infection, and chemical stimulation. MALAT1 is involved in regulating multiple cell behaviors, such as proliferation, apoptosis, differentiation, migration, epithelial-mesenchymal transition, autophagy, and morphological maintenance. Extensive evidence show that MALAT1 plays critical roles in the physiopathological process of embryo implantation, angiogenesis, tissue inflammation, tumor progression, liver fibrosis, cardiovascular remodeling, and diabetes progression by regulating gene transcription, forming RNA-protein complexes with proteins as a structural component, regulating protein activity, assisting protein localization, mediating epigenetic changes, or by acting as a competing endogenous RNA. Furthermore, MALAT1 can affect the sensitivity of chemotherapy and radiotherapy; therefore, it could be used as a potential drug target for chemotherapy and radiotherapy sensitization. The levels of MALAT1 are reported to be overexpressed in most tumor tissues or sera, and the expression levels of MALAT1 often affect the tumor size, stage, lymph node metastasis, and distant invasion. Therefore, MALAT1 can be used as a biomarker for early diagnosis, severity assessment, or prognostic assessment. This review outlines the current understanding of the biological role and function of MALAT1. In the meantime, we have summarized the mechanisms involved in the reulation of MALAT1 expression and the mechanisms by which MALAT1 regulates the physiological and pathological processes.

UVB-inhibited H19 activates melanogenesis by paracrine effects.

The long noncoding RNA H19 was reported to associate with melanogenesis. However, it remains unknown whether H19 expression will be changed by UVB irradiation and whether H19 will regulate melanocytes melanogenesis by paracrine effects. Here, we analysed the expression changes of H19 irradiated by UVB in keratinocytes and explored the mechanism of melanogenesis stimulated by H19 through paracrine effects. First, after keratinocytes were exposed to UVB irradiation, expression of H19 and pro-opiomelanocortin (POMC) was measured by qRT-PCR. Also, α-melanocyte-stimulating hormone (α-MSH) contents in cells supernatant were measured by ELISA. Then, H19 siRNAs were designed and transfected into keratinocytes by liposome. The expression changes of H19, POMC and α-MSH were detected. Besides, expression of p53 was detected by Western blot. After that, supernatant of keratinocytes with H19 siRNAs or negative control siRNA was cocultured with immortalized melanocyte line PIG1. Expression levels of MiTF, TYR, Rab27A, TYRP2, FSCN1 and MYO5A in PIG1 cells were detected by Western blot and qRT-PCR. We found that H19 expression of keratinocytes cells decreased after UVB irradiation. However, the levels of POMC, α-MSH and p53 were upregulated in UVB-irradiated cells. Compared with the negative control, H19 siRNAs could significantly increase the expression of POMC, α-MSH and p53. After supernatant of keratinocytes transfected with H19 siRNAs was cocultured with PIG1 cells, the levels of MiTF, TYR and Rab27A were upregulated in PIG1 cells. In conclusion, UVB-inhibited H19 may promote α-MSH secretion by p53 in keratinocytes and then regulate melanocytes melanogenesis through paracrine effects.