Ohara Go, Okabe Kazuto, Toyama Naoto, Ohta Yuya, Xinman Song, Ichimura Norihisa, Sato Kotaro, Urata Yusuke, Hibi Hideharu
Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Department of Oral and Maxillofacial Surgery, Iwata City Hospital, Iwata, Japan.
J Oral Pathol Med. 2023 Sep;52(8):718-726. doi: 10.1111/jop.13457. Epub 2023 Jun 15.
Tumor necrosis factor-related apoptosis-inducing ligand activates apoptotic pathways and could potentially be used in anticancer treatments. However, oral squamous cell carcinoma cells are known to be resistant to tumor necrosis factor-related apoptosis-inducing ligand-induced cell death. It has been previously reported that hyperthermia upregulates tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis in other cancers. As such, we evaluated whether hyperthermia upregulates tumor necrosis factor-related apoptosis-inducing ligand-mediated apoptosis in a tumor necrosis factor-related apoptosis-inducing ligand-resistant oral squamous cell carcinoma cell line.
The oral squamous cell carcinoma cell line HSC3 was cultured and divided into hyperthermia and control groups. We investigated the antitumor effects of recombinant human tumor necrosis factor-related apoptosis-inducing ligand using cell proliferation and apoptosis assays. Additionally, we measured death receptor 4 and 5 levels, and determined death receptor ubiquitination status, as well as E3 ubiquitin ligase targeting of death receptor in both hyperthermia and control groups before recombinant human tumor necrosis factor-related apoptosis-inducing ligand administration.
Treatment with recombinant human tumor necrosis factor-related apoptosis-inducing ligand produced greater inhibitory effects in the hyperthermia group than in the control group. Moreover, death receptor protein expression in the hyperthermia group was upregulated on the cell surface (and overall), although death receptor mRNA was downregulated. The half-life of death receptor was several hours longer in the hyperthermia group; concomitantly, E3 ubiquitin ligase expression and death receptor ubiquitination were downregulated in this group.
Our findings suggested that hyperthermia enhances apoptotic signaling by tumor necrosis factor-related apoptosis-inducing ligand via the suppression of death receptor ubiquitination, which upregulates death receptor expression. These data suggest that the combination of hyperthermia and tumor necrosis factor-related apoptosis-inducing ligand has implications in developing a novel treatment strategy for oral squamous cell carcinoma.
肿瘤坏死因子相关凋亡诱导配体可激活凋亡途径，具有用于抗癌治疗的潜力。然而，已知口腔鳞状细胞癌细胞对肿瘤坏死因子相关凋亡诱导配体诱导的细胞死亡具有抗性。此前有报道称，热疗可上调其他癌症中肿瘤坏死因子相关凋亡诱导配体诱导的凋亡。因此，我们评估了热疗是否能上调肿瘤坏死因子相关凋亡诱导配体介导的凋亡，该凋亡发生在对肿瘤坏死因子相关凋亡诱导配体耐药的口腔鳞状细胞癌细胞系中。
培养口腔鳞状细胞癌细胞系HSC3，并将其分为热疗组和对照组。我们使用细胞增殖和凋亡检测方法研究重组人肿瘤坏死因子相关凋亡诱导配体的抗肿瘤作用。此外，在给予重组人肿瘤坏死因子相关凋亡诱导配体之前，我们测量了热疗组和对照组中死亡受体4和5的水平，确定了死亡受体的泛素化状态，以及E3泛素连接酶对死亡受体的靶向作用。
重组人肿瘤坏死因子相关凋亡诱导配体治疗在热疗组中产生的抑制作用比对照组更大。此外，热疗组中死亡受体蛋白在细胞表面（及总体）的表达上调，尽管死亡受体mRNA表达下调。热疗组中死亡受体的半衰期延长了数小时；与此同时，该组中E3泛素连接酶表达和死亡受体泛素化下调。
我们的研究结果表明，热疗通过抑制死亡受体泛素化来增强肿瘤坏死因子相关凋亡诱导配体的凋亡信号，从而上调死亡受体表达。这些数据表明，热疗与肿瘤坏死因子相关凋亡诱导配体的联合应用对开发口腔鳞状细胞癌的新型治疗策略具有重要意义。
