Wu Yuan, Wan Xiao-Wen, Jiang Lin, Wang Wei, Zhu Jia-Jun, Shao Yi-Sen
Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Jiangxi University of Traditional Chinese Medicine, Nanchang, Jiangxi, China.
Kaohsiung J Med Sci. 2025 Jul 3:e70069. doi: 10.1002/kjm2.70069.
Rhaponitin (Rha) possesses anti-tumor activity and mediates the transcriptional activity of hypoxia-inducible factor (HIF)-1α that affects cisplatin (Cis) resistance. However, whether Rha can lessen Cis resistance in tongue squamous cell carcinoma (TSCC) by mediating HIF-1α activity is unclear. Cis-resistant SCC9 (SCC9-CisR) cells were treated with Cis, Rha, or Cis plus Rha to explore the effect of Rha on Cis resistance using a cell counting kit-8, flow cytometry, and tumor sphere formation assays. Stemness markers CD44 and SOX2 and HIF-1α mRNA levels were detected by quantitative PCR. The GSE115119 database and plugin iRegulon were employed to select target genes mediated by HIF-1α. Protein levels of HIF-1α, monocarboxylate transporter 4 (MCT4), and the Wnt/β-catenin pathway were measured by western blot. Subcutaneous xenograft models were constructed to explore the efficacy of Rha in combating Cis resistance. Rha repressed the growth and stemness of SCC9-CisR cells in vitro and in vivo. HIF-1α protein levels were markedly elevated in SCC9-CisR cells, yet Rha treatment attenuated the transcriptional activity of HIF-1α but not HIF-1α mRNA levels. Rha plus Cis repressed the viability and stemness of SCC9-CisR cells, but not HIF-1α-knockdown SCC9-CisR cells, compared with Cis alone. Rha-induced stemness inhibition and apoptosis in SCC9-CisR cells were overridden after HIF-1α overexpression. Rha inhibited the Wnt/β-catenin signaling by regulating the HIF-1α/MCT4 axis. In conclusion, Rha reduced cell stemness and enhanced Cis sensitivity in TSCC, which was achieved possibly via suppressing the Wnt/β-catenin signaling through mediation of the HIF-1α/MCT4 axis.
rhaponitin（Rha）具有抗肿瘤活性，并介导影响顺铂（Cis）耐药性的缺氧诱导因子（HIF）-1α的转录活性。然而，Rha是否能通过介导HIF-1α活性来减轻舌鳞状细胞癌（TSCC）中的顺铂耐药性尚不清楚。用顺铂、Rha或顺铂加Rha处理顺铂耐药的SCC9（SCC9-CisR）细胞，使用细胞计数试剂盒-8、流式细胞术和肿瘤球形成试验来探讨Rha对顺铂耐药性的影响。通过定量PCR检测干性标志物CD44和SOX2以及HIF-1α mRNA水平。利用GSE115119数据库和插件iRegulon选择由HIF-1α介导的靶基因。通过蛋白质印迹法检测HIF-1α、单羧酸转运蛋白4（MCT4）和Wnt/β-连环蛋白信号通路的蛋白质水平。构建皮下异种移植模型以探讨Rha对抗顺铂耐药性的疗效。Rha在体外和体内均抑制了SCC9-CisR细胞的生长和干性。SCC9-CisR细胞中HIF-1α蛋白水平明显升高，但Rha处理减弱了HIF-1α的转录活性，而不是HIF-1α mRNA水平。与单独使用顺铂相比，Rha加顺铂抑制了SCC9-CisR细胞的活力和干性，但对HIF-1α敲低的SCC9-CisR细胞没有抑制作用。HIF-1α过表达后，Rha诱导的SCC9-CisR细胞干性抑制和凋亡被逆转。Rha通过调节HIF-1α/MCT4轴抑制Wnt/β-连环蛋白信号传导。总之，Rha降低了TSCC中的细胞干性并增强了顺铂敏感性，这可能是通过介导HIF-1α/MCT4轴抑制Wnt/β-连环蛋白信号传导来实现的。
