Lou Hongfei, Fang Jugao, Li Pingdong, Zhou Weiguo, Wang Yang, Fan Erzhong, Li Ying, Wang Hong, Liu Zhongyan, Xiao Lei, Wang Chengshuo, Zhang Luo
Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China; Beijing Key Laboratory of nasal diseases, Beijing Institute of Otolaryngology, Beijing, PR China.
Department of Otolaryngology Head and Neck Surgery, Beijing TongRen Hospital, Capital Medical University, Beijing, PR China.
PLoS One. 2015 May 28;10(5):e0126463. doi: 10.1371/journal.pone.0126463. eCollection 2015.
Sinonasal squamous cell carcinoma (SSCC) and nasal inverted papilloma (NIP) represent the predominant type of malignant and benign tumors in sinonasal tract, respectively. CD4+ CD25+ Foxp3+ natural regulatory T (Treg) cells might play critical role(s) in the suppression of anti-tumor immune response and thus shed light on tumor progression from benign to malignant.
This study aimed to evaluate the frequency and suppressive capacity of Treg cells in SSCC compared to NIP and further to explore the underlying mechanisms.
Frequencies of Treg, Th1 and Th2 cells were evaluated by flow cytometry in tissue homogenate and peripheral blood from 31 SSCC patients, 32 NIP patients and 35 normal controls. Treg cells were tested for regulatory function by co-culture with effector T cells. CCR4 and its ligands, CCL22 and CCL17, were analyzed by flow cytometry and Luminex, respectively. The chemoattractant properties of CCR4/CCL22 and CCR4/CCL17 for Treg cells were assessed using the Boyden chamber technique, to elucidate the potential mechanisms of Treg recruitment in tumor microenvironment. Treg cells induction via TGF-β was assessed with transwells after local CD4+ Foxp3+ T cells were assessed by immunohistochemistry and TGF-β concentration was measured by Luminex.
Tumor-infiltrating Treg cells increased significantly from normal to NIP to SSCC (P ≤ 0.001 for normal vs. NIP and P = 0.004 for NIP vs. SSCC). Significantly elevated frequency and enhanced suppression capacity of circulating Treg cells in SSCC were detected compared to NIP and healthy controls, concomitant with Th1 decrease and Th2 increase. Apparently increased CCL22 attracted CCR4-expressing Treg cells to tumor microenvironment in SSCC, compared to NIP. SSCC produced significantly more TGF-β than NIP and thus possessed greater potential for Treg cell induction.
Frequency and suppressive capacity of Treg cells enhanced with progression of malignancy from NIP to SSCC. Circulating Treg cells were recruited to tumor tissue via CCR4/CCL22 signalling, whereas tumor-synthesised TGF-β contributed to induction of peripheral Treg cells.
鼻窦鳞状细胞癌（SSCC）和鼻内翻性乳头状瘤（NIP）分别是鼻窦最主要的恶性和良性肿瘤类型。CD4+CD25+Foxp3+自然调节性T（Treg）细胞可能在抑制抗肿瘤免疫反应中发挥关键作用，从而揭示肿瘤从良性发展为恶性的机制。
本研究旨在评估与鼻内翻性乳头状瘤相比，鼻窦鳞状细胞癌中Treg细胞的频率和抑制能力，并进一步探索其潜在机制。
采用流式细胞术评估31例鼻窦鳞状细胞癌患者、32例鼻内翻性乳头状瘤患者和35例正常对照者的组织匀浆和外周血中Treg、Th1和Th2细胞的频率。通过与效应T细胞共培养检测Treg细胞的调节功能。分别采用流式细胞术和Luminex技术分析CCR4及其配体CCL22和CCL17。采用Boyden小室技术评估CCR4/CCL22和CCR4/CCL17对Treg细胞的趋化特性，以阐明肿瘤微环境中Treg细胞募集的潜在机制。在通过免疫组织化学评估局部CD4+Foxp3+T细胞并采用Luminex技术测量TGF-β浓度后，使用transwell评估TGF-β诱导Treg细胞的情况。
从正常组织到鼻内翻性乳头状瘤再到鼻窦鳞状细胞癌，肿瘤浸润性Treg细胞显著增加（正常与鼻内翻性乳头状瘤相比，P≤0.001；鼻内翻性乳头状瘤与鼻窦鳞状细胞癌相比，P=0.004）。与鼻内翻性乳头状瘤和健康对照相比，鼻窦鳞状细胞癌中循环Treg细胞的频率显著升高且抑制能力增强，同时伴有Th1细胞减少和Th2细胞增加。与鼻内翻性乳头状瘤相比，鼻窦鳞状细胞癌中明显增加的CCL22将表达CCR4的Treg细胞吸引至肿瘤微环境。鼻窦鳞状细胞癌产生的TGF-β明显多于鼻内翻性乳头状瘤，因此具有更强的诱导Treg细胞的潜力。
从鼻内翻性乳头状瘤到鼻窦鳞状细胞癌，随着恶性程度的进展，Treg细胞的频率和抑制能力增强。循环Treg细胞通过CCR4/CCL22信号被募集至肿瘤组织，而肿瘤合成的TGF-β有助于外周Treg细胞的诱导。
