Wang Hao-Fan, Jiang Jian, Wu Jia-Shun, Zhang Mei, Pang Xin, Dai Li, Tang Ya-Ling, Liang Xin-Hua
State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
Department of Head and Neck Surgery, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, China.
Cancers (Basel). 2022 Aug 27;14(17):4151. doi: 10.3390/cancers14174151.
To study the role of target genes with aberrant DNA methylation in HPV+ HNSCC.
A HumanMethylation450 BeadChip array (Illumina) was used to identify differentially methylated genes. CCK-8, flow cytometry, wound healing, and cell invasion assays were conducted to analyze the biological roles of PRKCZ. Western blot, qRT-PCR, immunohistochemistry, and animal studies were performed to explore the mechanisms underlying the functions of PRKCZ.
We selected PRKCZ, which is associated with HPV infection, as our target gene. PRKCZ was hypermethylated in HPV+ HNSCC patients, and PRKCZ methylation status was negatively related to the pathological grading of HNSCC patients. Silencing PRKCZ inhibited the malignant capacity of HPV+ HNSCC cells. Mechanistically, HPV might promote DNMT1 expression via E6 to increase PRKCZ methylation. Cdc42 was required for the PRKCZ-mediated mechanism of action, contributing to the occurrence of epithelial-mesenchymal transition (EMT) in HPV+ HNSCC cells. In addition, blocking PRKCZ delayed tumor growth in HPV16-E6/E7 transgenic mice. Cdc42 expression was decreased, whereas E-cadherin levels increased.
We suggest that PRKCZ hypermethylation induces EMT via Cdc42 to act as a potent tumor promoter in HPV+ HNSCC.
研究DNA甲基化异常的靶基因在人乳头瘤病毒（HPV）阳性的头颈部鳞状细胞癌（HNSCC）中的作用。
采用HumanMethylation450 BeadChip芯片（Illumina公司）鉴定差异甲基化基因。进行CCK-8、流式细胞术、伤口愈合和细胞侵袭实验，以分析蛋白激酶Cζ（PRKCZ）的生物学作用。采用蛋白质免疫印迹法、定量逆转录聚合酶链反应（qRT-PCR）、免疫组织化学和动物实验，探讨PRKCZ发挥功能的潜在机制。
我们选择与HPV感染相关的PRKCZ作为靶基因。PRKCZ在HPV阳性的HNSCC患者中呈高甲基化，且PRKCZ甲基化状态与HNSCC患者的病理分级呈负相关。沉默PRKCZ可抑制HPV阳性的HNSCC细胞的恶性能力。机制上，HPV可能通过E6蛋白促进DNA甲基转移酶1（DNMT1）表达，从而增加PRKCZ甲基化。细胞分裂周期蛋白42（Cdc42）是PRKCZ介导的作用机制所必需的，它促使HPV阳性的HNSCC细胞发生上皮-间质转化（EMT）。此外，阻断PRKCZ可延缓HPV16-E6/E7转基因小鼠的肿瘤生长。Cdc42表达降低，而E-钙黏蛋白水平升高。
我们认为，PRKCZ高甲基化通过Cdc42诱导EMT，在HPV阳性的HNSCC中发挥强效肿瘤促进作用。
