Department of Pathology, University of Helsinki, HUSLAB and Helsinki University Hospital, P. O. Box 21, 00014 Helsinki, Finland.
Department of Pathology, University of Helsinki, Research Program for Clinical and Molecular Metabolism, P. O. Box 21, 00014 Helsinki, Finland.
Exp Mol Pathol. 2020 Jun;114:104435. doi: 10.1016/j.yexmp.2020.104435. Epub 2020 Mar 30.
In oropharyngeal squamous cell carcinoma (OPSCC), the expression pattern of toll-like receptors (TLRs), in comparison between human papillomavirus (HPV)-positive and -negative tumors differs. TLRs control innate immune responses by activating, among others, the nuclear factor-κΒ (NF-κΒ) signaling pathway. Elevated NF-κΒ activity is detectable in several cancers and regulates cancer development and progression. We studied TLR5 expression in 143 unselected consecutive OPSCC tumors, and its relation to HPV-DNA and p16 status, clinicopathological parameters, and patient outcome, and studied TLR5 stimulation and consecutive NF-κB cascade activation in vitro in two human OPSCC cell lines and immortalized human keratinocytes (HaCat). Clinicopathological data came from hospital registries, and TLR5 immunoexpression was evaluated by immunohistochemistry. Flagellin served to stimulate TLR5 in cultured cells, followed by analysis of the activity of the NF-κB signaling cascade with In-Cell Western for IκΒ and p-IκΒ. High TLR5 expression was associated with poor disease-specific survival in HPV-positive OPSCC, which typically shows low TLR5 immunoexpression. High TLR5 immunoexpression was more common in HPV-negative OPSCC, known for its less-favorable prognosis. In vitro, we detected NF-κΒ cascade activation in the HPV-positive OPSCC cell line and in HaCat cells, but not in the HPV-negative OPSCC cell line. Our results suggest that elevated TLR5 immunoexpression may be related to reduced NF-κΒ activity in HPV-negative OPSCC. The possible prognosis-worsening mechanisms among these high-risk OPSCC patients however, require further evaluation.
在口咽鳞状细胞癌（OPSCC）中，与 HPV 阳性和阴性肿瘤相比， Toll 样受体（TLR）的表达模式不同。TLR 通过激活核因子-κB（NF-κB）信号通路等来控制先天免疫反应。在几种癌症中可检测到 NF-κB 活性升高，它调节癌症的发生和发展。我们研究了 143 例未经选择的连续 OPSCC 肿瘤中 TLR5 的表达及其与 HPV-DNA 和 p16 状态、临床病理参数和患者预后的关系，并在两种人 OPSCC 细胞系和永生化人角质形成细胞（HaCat）中研究了 TLR5 刺激及其后续 NF-κB 级联激活。临床病理数据来自医院登记处，通过免疫组织化学评估 TLR5 的免疫表达。鞭毛蛋白用于刺激培养细胞中的 TLR5，然后用 In-Cell Western 分析 NF-κB 信号级联的活性，以检测 IκΒ 和 p-IκΒ 的活性。在 HPV 阳性 OPSCC 中，高 TLR5 表达与疾病特异性生存率降低相关，而 HPV 阳性 OPSCC 通常表现出低 TLR5 免疫表达。在 HPV 阴性 OPSCC 中，高 TLR5 免疫表达更为常见，其预后较差。在体外，我们检测到 HPV 阳性 OPSCC 细胞系和 HaCat 细胞中 NF-κB 级联的激活，但在 HPV 阴性 OPSCC 细胞系中未检测到。我们的结果表明，在 HPV 阴性 OPSCC 中，升高的 TLR5 免疫表达可能与 NF-κB 活性降低有关。然而，这些高危 OPSCC 患者中可能导致预后恶化的机制需要进一步评估。
