Single-cell sequencing highlights heterogeneity and malignant progression in actinic keratosis and cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (cSCC) is the second most frequent of the keratinocyte-derived malignancies with actinic keratosis (AK) as a precancerous lesion. To comprehensively delineate the underlying mechanisms for the whole progression from normal skin to AK to invasive cSCC, we performed single-cell RNA sequencing (scRNA-seq) to acquire the transcriptomes of 138,982 cells from 13 samples of six patients including AK, squamous cell carcinoma in situ (SCCIS), cSCC, and their matched normal tissues, covering comprehensive clinical courses of cSCC. We identified diverse cell types, including important subtypes with different gene expression profiles and functions in major keratinocytes. In SCCIS, we discovered the malignant subtypes of basal cells with differential proliferative and migration potential. Differentially expressed genes (DEGs) analysis screened out multiple key driver genes including transcription factors along AK to cSCC progression. Immunohistochemistry (IHC)/immunofluorescence (IF) experiments and single-cell ATAC sequencing (scATAC-seq) data verified the expression changes of these genes. The functional experiments confirmed the important roles of these genes in regulating cell proliferation, apoptosis, migration, and invasion in cSCC tumor. Furthermore, we comprehensively described the tumor microenvironment (TME) landscape and potential keratinocyte-TME crosstalk in cSCC providing theoretical basis for immunotherapy. Together, our findings provide a valuable resource for deciphering the progression from AK to cSCC and identifying potential targets for anticancer treatment of cSCC.

LncRNA-WAKMAR2 regulates expression of CLDN1 to affect skin barrier through recruiting c-Fos.

BACKGROUND: Chronic actinic dermatitis (CAD) is an immune-mediated photo-allergic skin disease. In the clinic, the treatment of this disease is hampered by the lack of proper understanding of the skin barrier dysfunction mechanism. OBJECTIVE: To illuminate the mechanism of skin barrier dysfunction in CAD. METHODS: Transcriptome sequencing and protein profiling were used to detect skin barrier injury-related genes. RNA pull down, a promoter-reporter gene assay, and chromatin isolation by RNA purification-sequencing were used to elucidate the effect of WAKMAR2 in skin barrier functionality. RESULTS: Transcriptome sequencing from patient's tissues showed a significantly decreased expression of WAKMAR2. Down-regulation of WAKMAR2 destroyed the keratinocyte barrier. Moreover, WAKMAR2 can directly bind to the c-Fos protein. This novel long non-coding RNA (LncRNA)-protein complexes were targeted to the CLDN1 promotor. Overexpression of WAKMAR2 enhanced the promoter activity of CLDN1, while the addition of AP-1 inhibitor could reverse this phenomenon. Furthermore, our in vivo results suggested that expression of WAKMAR2 was required for the repair of skin damage in mice induced by ultraviolet irradiation. CONCLUSIONS: We identified a crucial LncRNA (WAKMAR2) for the protection of the skin barrier in vitro and in vivo. Mechanically, it can specifically interact with c-Fos protein for the regulation of CLDN1, a finding which could be applied for CAD treatment.

Retraction Notice to: Hypoxic tumor-derived exosomal circular RNA SETDB1 promotes invasive growth and EMT via the miR-7/Sp1 axis in lung adenocarcinoma.

[This retracts the article DOI: 10.1016/j.omtn.2021.01.019.].

RTP4 is a novel prognosis-related hub gene in cutaneous melanoma.

OBJECTIVE: Melanoma accounts for 80% of skin cancer deaths. The pathogenesis of melanoma is regulated by gene networks. Thus, we aimed here to identify gene networks and hub genes associated with melanoma and to further identify their underlying mechanisms. METHODS: GTEx (normal skin) and TCGA (melanoma tumor) RNA-seq datasets were employed for this purpose. We conducted weighted gene co-expression network analysis (WGCNA) to identify key modules and hub genes associated with melanoma. Log-rank analysis and multivariate Cox model analysis were performed to identify prognosis genes, which were validated using two independent melanoma datasets. We also evaluated the correlation between prognostic gene and immune cell infiltration. RESULTS: The blue module was the most relevant for melanoma and was thus considered the key module. Intersecting genes were identified between this module and differentially expressed genes (DEGs). Finally, 72 genes were identified and verified as hub genes using the Oncomine database. Log-rank analysis and multivariate Cox model analysis identified 13 genes that were associated with the prognosis of the metastatic melanoma group, and RTP4 was validated as a prognostic gene using two independent melanoma datasets. RTP4 was not previously associated with melanoma. When we evaluated the correlation between prognostic gene and immune cell infiltration, we discovered that RTP4 was associated with immune cell infiltration. Further, RTP4 was significantly associated with genes encoding components of immune checkpoints (PDCD1, TIM-3, and LAG3). CONCLUSIONS: RTP4 is a novel prognosis-related hub gene in cutaneous melanoma. The novel gene RTP4 identified here will facilitate the exploration of the molecular mechanism of the pathogenesis and progression of melanoma and the discovery of potential new target for drug therapy.

Applications of Single-Cell Sequencing in Dermatology.

Single-cell sequencing (SCS) is a promising new technique used to assess the genomics, transcriptomics, epigenetics, and other multi-omics at the single-cell level. In addition to elucidating the immune microenvironment and revealing the pathomechanisms of disease and drug resistance, SCS can profile the actual state of an individual cell and identify a novel cell type and differentiation trajectories, which cannot be achieved by bulk tissue sequencing technique. SCS technique serves as powerful tools to explore more meaningful biomarkers of diagnosis, prognosis, and new therapeutic targets in clinical practice. The SCS technique has been widely applied in the field of dermatology. In this review, we summarize the advances of SCS in dermatology.

The Associations of Androgen-Related Genes CYP21A2 and CYP19A1 with Severe Acne Vulgaris in Patients from Southwest China.

OBJECTIVE: Androgens acting through the androgen receptor play a crucial role in the pathogenesis of acne. This study aimed to identify whether two key genes (CYP21A2 and CYP19A1) involved in the synthesis and metabolism of androgens were associated with Pillsbury III-IV severe acne vulgaris. METHODS: We carried out a standard questionnaire survey about acne and enlisted 600 Pillsbury III-IV severe acne vulgaris patients and 652 healthy controls of Han Chinese descent from Yunnan, China in the study. Twenty-two single nucleotide polymorphisms (SNPs) were genotyped by SNaPshot assay and analyzed for association with severe acne. RESULTS: There was no significant difference in gender between the two groups (P = 0.085), and the age of the acne case group was significantly lower than that of the control group (P < 0.001). Our results revealed that only two SNPs, rs6474 (p.Arg102Lys) (P = 0.001) and rs6465 (P = 0.025) of the CYP21A2 gene were significantly associated with severe acne among the Han Chinese. When subjects were divided into males and females, significant associations were observed only in male patients with severe acne vulgaris for four variants: CYP21A2 rs6474 (p.Arg102Lys) (P = 0.002); CYP21A2 rs6465 (P = 0.012); CYP19A1 rs8023263 (P = 0.037); and CYP19A1 rs2470152 (P = 0.007). Haplotype analyses showed that the distribution of CYP21A2 haplotypes was significantly associated with male patients, while no association of CYP19A1 haplotypes was observed. The structure of the human CYP21A2 consists of two substrate binding sites and one substrate access channel. CONCLUSION: This study shed a light on a potentially important effect of CYP21A2 and CYP19A1 genes in severe acne vulgaris in the Han Chinese, especially for male patients. Future studies using independently verified datasets from a broader geographical spectrum will be valuable in identifying the causal and functional variants responsible for severe acne vulgaris within the CYP19A1 and CYP21A2 genes.

Hypoxic tumor-derived exosomal circular RNA SETDB1 promotes invasive growth and EMT via the miR-7/Sp1 axis in lung adenocarcinoma.

Hypoxia is a common feature of solid tumors and has been associated with tumor aggressiveness and poor prognosis. Exosomes are involved in mediating cellular-environment interactions. Circular RNAs (circRNAs) are a class of non-coding RNA broadly found in cells and exosomes. However, the functions and regulatory mechanisms of exosomal circRNAs induced by hypoxia remain poorly understood in lung adenocarcinoma (LUAD) development. Differentially expressed circRNAs were identified between exosomes extracted from hypoxic and normoxic conditions through microarray analysis. We focused on hsa-circ-0003439 found on chromosome 1 and derived from SET domain bifurcated histone lysine methyltransferase 1 (SETDB1), and thus we named it circSETDB1. We discovered that exosomes obtained from hypoxic LUAD cells improved the migration, invasion, and proliferation capacity of normoxic LUAD cells. circSETDB1 was found to be significantly upregulated in hypoxia-induced exosomes from LUAD cell lines compared with exosomes in the normal condition. Moreover, knockdown of circSETDB1 significantly inhibited cell malignant growth in vitro. Importantly, we showed that circSETDB1 was upregulated in serum exosomes in LUAD patients, and exosomal circSETDB1 levels were closely associated with disease stage. Finally, using RNA immunoprecipitation (RIP), bioinformatics, and luciferase reporter assays, we elucidated the implication of a circSETDB1/miR-7/specificity protein 1 (Sp1) axis in the development and epithelial-mesenchymal transition (EMT) of lung adenocarcinoma.

HMGA2 regulates circular RNA ASPH to promote tumor growth in lung adenocarcinoma.

In this study, we identified a circular form of ASPH RNA (circASPH), expression of which was upregulated in lung adenocarcinoma and the human lung adenocarcinoma cell lines. We also found a positive correlation between circASPH level and the T and N stages of lung adenocarcinoma patients. Patients with higher levels of circASPH had a shorter overall survival. Moreover, we demonstrated that circASPH was directly regulated by HMGA2 and Twist1. The direct positive regulation of circASPH by Twist1 was dependent on the presence of HMGA2. Functional assays indicated that circASPH promoted the proliferation, migration, and invasion of lung adenocarcinoma cell lines in vitro. The promoting effect of tumor growth by circASPH was also observed in vivo. Mechanistically, circASPH was identified to act as a molecular sponge for miR-370 and abrogate miR-370-mediated inhibition of HMGA2. Finally, we demonstrated that the oncogenic function of circASPH was HMGA2-dependent. These findings reveal the oncogenic functions of the HMGA2-circASPH-HMGA2 axis and may be useful in developing circRNA-based therapeutic strategies for lung adenocarcinoma.

miR-541 suppresses proliferation and invasion of squamous cell lung carcinoma cell lines via directly targeting high-mobility group AT-hook 2.

An increasing number of studies have demonstrated that micro-ribonucleic acids (miRNAs) are important tumor suppressors during carcinogenesis. However, the function of miRNA-541 (miR-541) in malignancies, especially lung cancer, has not been widely reported. In this study, miR-541 expression was significantly decreased in squamous cell lung carcinoma (SCLC) cancerous tissue and SCLC cell lines. To analyze miR-541 function in SCLC, we overexpressed miR-541 in SCLC cell lines (SK-MES-1 and H226). According to the CCK8, wound scratch, and transwell invasion assay results, miR-541 overexpression significantly inhibited SCLC cell proliferation, migration, and invasion ability. Next, using RT-PCR, Western blotting, immunocytochemistry, and luciferase assays, HMGA2 was identified, for the first time, as a direct regulatory target of miR-541 in SK-MES-1 and H226 cells. Furthermore, upregulating HMGA2 expression significantly alleviated the suppressive effects of miR-541 on SK-MES-1 and H226 cell proliferation, migration, and invasion. In summary, our study revealed that miR-541 inhibited SCLC proliferation and invasion by directly targeting HMGA2.

ANG Promotes Proliferation and Invasion of the Cell of Lung Squamous Carcinoma by Directly Up-Regulating HMGA2.

OBJECTIVE: To determine the mechanism of Angiogenin(ANG) function involved in the carcinogenesis of lung squamous cell carcinoma. METHODS: 12 patients' normal tissue and cancerous tissue were collected. ANG expression in the squamous cell carcinoma of the lung was evaluated by qRT-PCR and western-blot. The regulation of ANG on proliferation, migration, invasion, and apoptosis of SK-MES-1 cells were analyzed by Cell Counting Kit-8, Transwell migration chamber, Transwell invasion chamber, and Annexin V-FITC assay, respectively. PCR array was utilized for screening potential target genes of ANG. Chromatin immunoprecipitation(ChIP) assays and luciferase assay were adopted for investigation of ANG's direct regulation on HMGA2. RESULTS: ANG expression is increased in the squamous cell carcinoma of the lung tissue. In vitro experiments results indicated that overexpression of ANG promotes proliferation and invasion capability of SK-MES-1 cells. The candidate proliferation, migration, and invasion related ANG target gene found was HMGA2, expression levels of which were also enhanced in lung squamous cell carcinoma tissue. The direct regulation of ANG on HMGA2 was verified by ChIP and luciferase assay results. Furthermore, down-regulating HMGA2 significantly alleviated the suppression effects of ANG on proliferation, migration, and invasion of SK-MES-1 cells. CONCLUSIONS: Our data illustrated the mechanisms that ANG promoted the cell of SQCLC proliferation, migration, and invasion capacity via directly up-regulating HMGA2.

Quantum Delayed-Choice Experiment with a Beam Splitter in a Quantum Superposition.

A quantum system can behave as a wave or as a particle, depending on the experimental arrangement. When, for example, measuring a photon using a Mach-Zehnder interferometer, the photon acts as a wave if the second beam splitter is inserted, but as a particle if this beam splitter is omitted. The decision of whether or not to insert this beam splitter can be made after the photon has entered the interferometer, as in Wheeler's famous delayed-choice thought experiment. In recent quantum versions of this experiment, this decision is controlled by a quantum ancilla, while the beam splitter is itself still a classical object. Here, we propose and realize a variant of the quantum delayed-choice experiment. We configure a superconducting quantum circuit as a Ramsey interferometer, where the element that acts as the first beam splitter can be put in a quantum superposition of its active and inactive states, as verified by the negative values of its Wigner function. We show that this enables the wave and particle aspects of the system to be observed with a single setup, without involving an ancilla that is not itself a part of the interferometer. We also study the transition of this quantum beam splitter from a quantum to a classical object due to decoherence, as observed by monitoring the interferometer output.

TNF-308 G/A polymorphism and risk of acne vulgaris: a meta-analysis.

BACKGROUND: The -308 G/A polymorphism in the tumor necrosis factor (TNF) gene has been implicated in the risk of acne vulgaris, but the results are inconclusive. The present meta-analysis aimed to investigate the overall association between the -308 G/A polymorphism and acne vulgaris risk. METHODS: We searched in Pubmed, Embase, Web of Science and CNKI for studies evaluating the association between the -308 G/A gene polymorphism and acne vulgaris risk. Data were extracted and statistical analysis was performed using STATA 12.0 software. RESULTS: A total of five publications involving 1553 subjects (728 acne vulgaris cases and 825 controls) were included in this meta-analysis. Combined analysis revealed a significant association between this polymorphism and acne vulgaris risk under recessive model (OR = 2.73, 95% CI: 1.37-5.44, p = 0.004 for AA vs. AG + GG). Subgroup analysis by ethnicity showed that the acne vulgaris risk associated with the -308 G/A gene polymorphism was significantly elevated among Caucasians under recessive model (OR = 2.34, 95% CI: 1.13-4.86, p = 0.023). CONCLUSION: This meta-analysis suggests that the -308 G/A polymorphism in the TNF gene contributes to acne vulgaris risk, especially in Caucasian populations. Further studies among different ethnicity populations are needed to validate these findings.

Two new susceptibility loci 1q24.2 and 11p11.2 confer risk to severe acne.

Severe acne is a chronic inflammatory skin disorder characterized by widespread inflammatory lesions including nodules, cysts and potential scarring. Here we perform the first genome-wide association study of severe acne in a Chinese Han population comprising 1,056 cases and 1,056 controls using the Illumina HumanOmniZhongHua-8 BeadChip. In an independent cohort of 1,860 cases and 3,660 controls of Chinese Han, we replicate 101 SNPs of which 3 showed consistent association. We identify two new susceptibility loci at 11p11.2 (DDB2, rs747650, P(combined)=4.41 × 10⁻9 and rs1060573, P(combined)=1.28 × 10⁻8) and 1q24.2 (SELL, rs7531806, P(combined)=1.20 × 10⁻8) that are involved in androgen metabolism, inflammation processes and scar formation in severe acne. These results point to new genetic susceptibility factors and suggest several new biological pathways related to severe acne.

MicroRNA-499 rs3746444 polymorphism and autoimmune diseases risk: a meta-analysis.

BACKGROUND AND OBJECTIVE: MicroRNA (miR)-499 rs3746444 polymorphisms may participate in the pathogenesis of autoimmune diseases, but the results remain conflicting. We further investigated this association using a meta-analysis. METHODS: We conducted a retrieval of studies and obtained the eligible studies if they met inclusion criteria. Two researchers independently extracted the data from original articles. The genotype frequencies were analysed using Stata software. RESULTS: We finally archived six eligible studies that included 1,118 cases and 1,673 controls. After pooling the data, the results indicated that homozygote TT had an overall association with autoimmune diseases (TC + CC vs. TT: odds ratio [OR] 1.31, 95% CI 1.11-1.55, p = 0.001). The allele C, genotype TC and CC, may be associated with rheumatoid arthritis (RA) risks in Mediterranean populations (C vs. T: OR 2. 00, 95% CI 1.37-2.91, p < 0.001; TC vs. CC + TT: OR 1.76, 95% CI 1.27-2.44; p = 0.001; CC vs. TC + TT: OR 2.31, 95% CI 1.24-4.27, p = 0.008; CC vs. TT: OR 2.92, 95% CI 1.59-5.37, p = 0.001; TC vs. TT: OR 1.98, 95% CI 1.42-2.77). The genotype TT may decrease the risk of RA in Mediterranean populations (TC + CC vs. TT: OR 2.15, 95% CI 1.57-2.94, p < 0.001) rather than in East Asians. CONCLUSIONS: This study suggested that miR-499 polymorphisms were associated with a significantly increased risk of RA in Mediterranean populations.

Lamellar body distribution, ceramidase expression and skin barrier function in lesions of polymorphous light eruption / 中华皮肤科杂志

Objective To investigate the correlation of epidermal distribution of lamellar bodies and expression of ceramidase with skin barrier dysfunction in polymorphous light eruption.Methods Forty-seven patients with polymorphous light eruption and 40 healthy volunteers were recruited into this study.Noninvasive instruments were used to measure skin sebum content,transepidermal water loss(TEWL)and water content in stratum corneum in all of the subjects.Then,tissue specimens were obtained from the lesions at sunexposed sites in the patients and normal skin of the healthy volunteers.The ultrastructure and distribution of lamellar bodies were observed with transmission electron microscopy in five lesion and control specimens.Immunohistochemistry was performed to detect the expression of ceramidase in the tissue specimens.Results Compared with the normal skin from healthy volunteers,the lesions from patients showed decreased number of lamellar bodies in the granular layer and prick cell layer with a disorganized arrangement.Ceramidase was positively expressed in 20 lesion specimens and 36 normal control specimens,weakly expressed in 21 lesion specimens and 4 normal control specimens,and negative in 6 lesion specimens; there was a significant difference in the expression of ceramidase between the lesion specimens and normal control specimens(P ＜ 0.01).The lesions also showed high TEWL(34.2191 ± 12.70 vs.16.8350 ± 6.50,P ＜ 0.01),lower water content in stratum corneum(22.7319 ± 8.71 vs.29.4250 ± 5.08,P ＜ 0.01)and similar skin sebum content compared with the normal skin.Conclusions There is a disturbance in the synthesis of ceramide in patients with polymorphous light eruption,which may contribute to the impairment of skin barrier.