PDF(Pubmed)
Abstract：
Human papillomavirus type 8 (HPV8), a cutaneous genus beta HPV type, has co-carcinogenic potential at sun-exposed sites in patients suffering from the inherited skin disease epidermodysplasia verruciformis (EV). We had previously shown that Langerhans cells responsible for epithelial immunosurveillance were strongly reduced at infected sites and that the HPV8 E7 protein interferes with the CCAAT/enhancer-binding protein (C/EBP)β to suppress the Langerhans cell chemokine CCL20. At the same time, however, we observed that EV lesions are heavily infiltrated with inflammatory immune cells, which is similar to the situation in HPV8 E6 transgenic mice. To identify critical inflammatory factors, we used a broad multiplex approach and found that the monocyte attracting chemokine CCL2 was significantly and strongly induced by HPV8 E6 but not E7-expressing HaCaT cells, which were used as a model for UV-damaged skin keratinocytes. Conditioned media from HPV8 E6-expressing keratinocytes enhanced CCL2-receptor (CCR2)-dependent monocyte recruitment in vitro, and macrophages predominated in the stroma but were also detected in the epidermal compartment of EV lesions in vivo. CCL2 induction by HPV8 E6 was even stronger than stimulation with the proinflammatory cytokine TNF-α, and both HPV8 E6 and TNF-α resulted in substantial suppression of the transcription factor C/EBPα. Using RNAi-mediated knockdown and overexpression approaches, we demonstrated a mechanistic role of the recently identified C/EBPα/miR-203/p63 pathway for HPV8 E6-mediated CCL2 induction at protein and transcriptional levels. Epithelial co-expression of p63 and CCL2 was confirmed in HPV8 E6-expressing organotypic air-liquid interface cultures and in lesional EV epidermis in vivo. In summary, our data demonstrate that HPV8 oncoproteins actively deregulate epidermal immune homeostasis through modulation of C/EBP factor-dependent pathways. While HPV8 E7 suppresses immunosurveillance required for viral persistence, the present study provides evidence that E6 involves the stemness-promoting factor p63 to support an inflammatory microenvironment that may fuel carcinogenesis in EV lesions.
摘要：
人乳头瘤病毒8型（HPV8），皮肤属β型HPV，患有遗传性皮肤疾病疣状表皮发育不良（EV）的患者在日晒部位具有共同致癌潜力。我们先前已经表明，负责上皮免疫监视的朗格汉斯细胞在感染部位大大减少，并且HPV8E7蛋白干扰CCAAT/增强子结合蛋白（C/EBP）β以抑制朗格汉斯细胞趋化因子CCL20。同时,然而,我们观察到EV病变严重浸润有炎症免疫细胞，这与HPV8E6转基因小鼠的情况相似。为了确定关键的炎症因子，我们使用了广泛的多重方法，发现单核细胞吸引趋化因子CCL2被HPV8E6而不是E7表达HaCaT细胞显著和强烈地诱导，其用作UV损伤的皮肤角质形成细胞的模型。来自表达HPV8E6的角质形成细胞的条件培养基在体外增强了CCL2受体（CCR2）依赖性单核细胞募集，和巨噬细胞在基质中占主导地位，但在体内EV病变的表皮区室中也检测到。HPV8E6对CCL2的诱导甚至强于促炎细胞因子TNF-α的刺激，HPV8E6和TNF-α均导致转录因子C/EBPα的实质性抑制。使用RNAi介导的敲低和过表达方法，我们证明了最近鉴定的C/EBPα/miR-203/p63通路在HPV8E6介导的CCL2诱导蛋白和转录水平的机制作用.在表达HPV8E6的器官型气-液界面培养物和体内病变EV表皮中证实了p63和CCL2的上皮共表达。总之,我们的数据表明,HPV8癌蛋白通过调节C/EBP因子依赖性通路,主动去调节表皮免疫稳态.虽然HPV8E7抑制了病毒持续所需的免疫监视，本研究提供的证据表明,E6涉及干性促进因子p63,以支持可能助长EV病变癌变的炎症微环境.
