Background: Cancer-associated fibroblasts have been reported to play a central role in driving cancer progression, promoting metastasis, and conferring resistance to therapy in HNSCC. Methods: Indirect and direct co-culture models of HPV-positive and HPV-negative HNSCC cells with fibroblasts were developed to study the effect of fibroblasts on cancer cells. ELISA was used to measure IL-6 secretion in these models. To dissect the underlying signalling mechanisms, the effects of IL-6, an IL-6 receptor (IL-6R) inhibitor, a MAPK/ERK inhibitor, and a JAK/STAT inhibitor were evaluated. Epithelial-to-mesenchymal transition (EMT) was assessed by measuring EMT markers and conducting scratch assays and spheroid assays. Radioresistance was evaluated using clonogenic assays. Additionally, radioresistant (RR) cell lines were established from parental cells to examine the correlation between radioresistance and EMT. Results: Fibroblasts were found to drive EMT-like changes and heightened radioresistance in HNSCC cells through IL-6 secretion. Remarkably, these Fb-driven effects were robustly reversed using IL-6R and MAPK/ERK inhibitors in both HPV-positive and HPV-negative cell lines, whereas JAK/STAT inhibitors proved effective only in HPV-negative cells. RR cell lines exhibit a more aggressive phenotype than their parental counterparts, marked by pronounced EMT features and heightened resistance to radiotherapy. Importantly, these aggressive characteristics were substantially attenuated by targeting IL-6R or MAPK/ERK pathways. Conclusions: This study highlights the critical role of fibroblast-secreted IL-6 in driving and maintaining EMT and radioresistance in HNSCC, resulting in a more aggressive tumour phenotype. Targeting the IL-6/IL-6R/ERK pathway emerges as a promising therapeutic approach for combating CAF-driven tumour progression and improving clinical outcomes in patients with aggressive, therapy-resistant HNSCC.
背景：已有报道指出，癌症相关成纤维细胞在头颈部鳞状细胞癌（HNSCC）中，对驱动癌症进展、促进转移以及赋予治疗抵抗性起着核心作用。方法：本研究建立了HPV阳性和HPV阴性HNSCC细胞与成纤维细胞的间接及直接共培养模型，以探究成纤维细胞对癌细胞的影响。采用酶联免疫吸附测定（ELISA）检测这些模型中的IL-6分泌水平。为剖析其潜在的信号机制，评估了IL-6、IL-6受体（IL-6R）抑制剂、MAPK/ERK抑制剂以及JAK/STAT抑制剂的作用。通过检测上皮-间质转化（EMT）标志物、进行划痕实验和球体形成实验来评估EMT。采用克隆形成实验评估放射抵抗性。此外，从亲代细胞中建立了放射抵抗（RR）细胞系，以研究放射抵抗性与EMT之间的相关性。结果：研究发现，成纤维细胞通过分泌IL-6驱动HNSCC细胞发生EMT样改变并增强其放射抵抗性。值得注意的是，在HPV阳性和HPV阴性细胞系中，使用IL-6R和MAPK/ERK抑制剂均能有效逆转这些由成纤维细胞驱动的效应，而JAK/STAT抑制剂仅在HPV阴性细胞中显示出效果。与亲代细胞相比，RR细胞系表现出更具侵袭性的表型，其特征是显著的EMT标志和更强的放射治疗抵抗性。重要的是，通过靶向IL-6R或MAPK/ERK通路，这些侵袭性特征得到了显著抑制。结论：本研究强调了成纤维细胞分泌的IL-6在驱动和维持HNSCC的EMT及放射抵抗性中的关键作用，从而导致更具侵袭性的肿瘤表型。靶向IL-6/IL-6R/ERK通路成为对抗CAF驱动的肿瘤进展、改善侵袭性及治疗抵抗性HNSCC患者临床结局的一种有前景的治疗策略。
肿瘤(癌症)患者之家