Although laboratory studies have implicated the high mobility group box 1 (HMGB1) in melanoma, its clinical relevance remains unclear. We analyzed nearly 100 cases of human melanoma and found that HMGB1 was highly overexpressed in melanoma samples relative to normal skin and nevi tissues. Significantly, higher levels of HMGB1 correlated with more advanced disease stages and with poorer survival in melanoma patients. Unlike the well-documented pro-inflammatory role of the extracellular HMGB1, we found that its intracellular activity is necessary for melanoma cell proliferation. An absolute dependency of melanoma cell proliferation on HMGB1 was underscored by the marked response of cell cycle arrest and senescence to HMGB1 knockdown. We demonstrated that HMGB1 deficiency-induced inhibition of cell proliferation was mediated by p21, which was induced via a Sp1-dependent mechanism. Taken together, our data demonstrate a novel oncogenic role of HMGB1 in promoting human melanoma cell proliferation and have important implications in melanoma patient care.

The reduced expression of miR-142-3p/5p in CD4 + T cells of SLE patients caused T cell hyperactivity and B cell hyperstimulation. This study aimed to investigate the mechanisms of regulating miR-142-3p/5p expression in SLE CD4 + T cells. The BCL-6 expression was significantly increased in SLE CD4 + T cells compared with normal controls, and the BCL-6 expression was inversely correlated with miR-142-3p/5p expression. BCL-6 suppresses the expression of miR-142-3p/5p by increasing H3K27me3 level and reducing H3K9/K14ac levels in SLE CD4 + T cells. BCL-6 regulates histone modifications in miR-142 promoter by recruiting EZH2 and HDAC5. Furthermore, we observed significantly decreased CD40L, ICOS, and IL-21 expression levels in SLE CD4 + T cells with BCL-6 interference, and obviously reduced autoantibody IgG production in autologous B cells co-cultured with BCL-6 inhibited SLE CD4 + T cells. Our study found that increased BCL-6 up-regulates H3K27me3 and down-regulates H3K9/14ac at miR-142 promoter in SLE CD4 + T cells. These factors induce a declination in miR-142-3p/5p expression, consequently resulting in CD4 + T cell hyperactivity.

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Chronic sun exposure-induced histone H3 hyperacetylation may play a critical role in the pathogenesis of skin photoageing.

Antihistamines are the first-line treatment for chronic urticaria (CU). However, some CU patients are relatively refractory to antihistamines. The mechanism underlying the interindividual variation is still unknown. The α-chain of the high-affinity IgE receptor is crucial to the IgE-mediated allergic response. The present study is to investigate whether FCER1A polymorphisms are associated with the risk of CSU, and to determine whether these polymorphisms influence the therapeutic efficacy of nonsedating H1-antihistamines. 191 CSU patients treated by nonsedating H1-antihistamines monotherapy (including desloratadine, mizolastine or fexofenadine) were prospectively enrolled in this study. The response to antihistamines monotherapy was assessed by urticaria activity score (UAS7) after 4 weeks of treatment. FCER1A rs2298805, rs10908703 and rs2494262 genotypes were determined by Sequenom Mass Array technology or direct sequencing. There was significant difference in the allele frequency of rs2298805A between CSU patients and 177 healthy subjects (5.3 vs 10.2 %, P = 0.012, OR = 0.491, 95 % CI 0.278-0.865), and also significant difference in the allele frequency of rs2298805A between effective and ineffective groups (7.5 vs 1.0 %, P = 0.015, OR = 8.328, 95 %CI 1.1-63.039). In addition, rs2298805 polymorphism was significantly associated with total serum IgE concentrations (P = 0.011). There were no differences in the rs10908703 and rs2494262 either between CSU patients and healthy controls, or between effective and ineffective groups. These data suggest that rs2298805 might be associated with risk for CSU and the therapeutic efficacy of nonsedating H1-antihistamines in Chinese patients with CSU.