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In psoriasis, tumor necrosis factor (TNF)-α is a key pro-inflammatory cytokine that activates keratinocytes to produce other inflammatory mediators. In addition, increased serum or plasma TNF-α levels are considered to be biomarkers of psoriasis. Circulating cell-free DNA (cfDNA) originates from apoptotic or necrotic cells and reflects the severity of cellular damage. Although cfDNA has recently attracted attention as a marker in the diagnosis and prognosis of various disorders, there are few reports of its clinical implications in the field of dermatology including psoriasis. The aim of this study was to investigate whether the TNF-α gene is present in the cfDNA, and whether its levels can be utilized as a biomarker for patients with psoriasis. cfDNA was isolated from serum samples of 79 patients with psoriasis vulgaris and 29 with psoriatic arthritis. The levels of TNF-α in the cfDNA were assessed by droplet digital polymerase chain reaction. In this study, we made two novel findings. First, circulating TNF-α DNA levels in the cfDNA were significantly higher in patients with psoriasis than in healthy controls. In addition, the area under the curve was 0.91, suggesting that serum TNF-α DNA levels are effective as a diagnostic biomarker. Second, the levels of TNF-α DNA copies in the cfDNA were positively correlated with the Psoriasis Area and Severity Index (PASI) score in the group of patients with a PASI score higher than 10. Generally, a PASI score of more than 10 is defined as severe psoriasis; therefore, the levels of TNF-α DNA copies in the cfDNA could be a biomarker for severity in patients with severe psoriasis. Further studies are needed to establish serum TNF-α DNA levels as a novel biomarker of psoriasis.

Background Extramammary Paget's disease (EMPD) is a rare malignant skin cancer. One of the hallmarks of cancers, including EMPD, is an enhancement of aerobic glycolysis, which is also known as the Warburg effect. In the last step of glycolysis, the enzyme lactate dehydrogenase A (LDHA) catalyzes the conversion of pyruvate to lactic acid, the accumulation of which contributes to the creation of an acidic tumour microenvironment. This in turn results in immunosuppression in various types of cancers. However, the contribution of these pathways has not been well-studied in EMPD. Objective To investigate the significance of the Warburg effect and its contribution to the tumour immune microenvironment in EMPD. Methods The mRNA expression levels of molecules involved in glycolysis and immune-related cytokines were examined by ddPCR. The number of immune cells was assessed by immunohistochemistry (IHC). Results The levels of two glycolytic enzymes, HK2 and LDHA, in tumour tissues were significantly increased compared to those in paired-normal tissues. IHC analyses revealed increased numbers of PD-L1+ , PD-1+ , CD163+ M2 macrophages, Iba1+ macrophages and Foxp3+ Tregs that were associated with high LDHA levels in EMPD. ddPCR demonstrated that multiple cytokines including IL-4, IL-6, IL-10, TGF-β and CCL-2 were upregulated and associated with high LDHA levels in EMPD. Statistical analyses showed that IL-6 mRNA expression correlated with the number of CD163+ , Iba-1+ and Foxp3+ cells. Conclusion The Warburg effect contributes to immunomodulation in the tumour microenvironment and further elucidation may lead to better understanding of the pathogenesis of EMPD.

Background The development of BRAF/MEK inhibitors in patients with metastatic melanoma harboring BRAF mutations has garnered attention for liquid biopsy to detect BRAF mutations in cell-free DNA (cfDNA) using droplet digital PCR (ddPCR) or next-generation sequencing methods. Objective To investigate gene mutations in tumor DNA and cfDNA collected from 43 melanoma patients and evaluate their potential as biomarkers. Methods ddPCR and CAncer Personalized Profiling by deep Sequencing (CAPP-Seq) techniques were performed to detect gene mutations in plasma cfDNA obtained from patients with metastatic melanoma. Results Gene variants, including BRAF, NRAS, TP53, GNAS, and MET, were detectable in the plasma cfDNA, and the results were partially consistent with the results of those identified in the tissues. Among the variants examined, copy numbers of MET mutations were consistent with the disease status in two melanoma patients. Conclusion Liquid biopsy using CAPP-Seq and ddPCR has the potential to detect tumor presence and mutations, especially when tissue biopsies are unavailable. MET mutations in cfDNA may be a potential biomarker in patients with metastatic melanoma.

Recombinant adeno-associated virus (AAV) vectors are powerful tools for both basic neuroscience experiments and clinical gene therapies for neurological diseases. Intravascularly administered self-complementary AAV9 vectors can cross the blood-brain barrier. However, AAV9 vectors are of limited usefulness because they mainly transduce astrocytes in adult animal brains and have restrictions on foreign DNA package sizes. In this study, we show that intracardiac injections of tyrosine-mutant pseudotype AAV9/3 vectors resulted in extensive and widespread transgene expression in the brains and spinal cords of adult mice. Furthermore, the usage of neuron-specific promoters achieved selective transduction of neurons. These results suggest that tyrosine-mutant AAV9/3 vectors may be effective vehicles for delivery of therapeutic genes, including miRNAs, into the brain and for treating diseases that affect broad areas of the central nervous system.