Department of Pharmacy, Guangdong Provincial Key Laboratory of Major Obstetric Diseases, Guangdong Provincial Clinical Research Center for Obstetrics and Gynecology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510150, China.
School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, 511436, China.
Oncol Res. 2024 Nov 13;32(12):1891-1902. doi: 10.32604/or.2024.048778. eCollection 2024.
Polymethoxylated flavones (PMFs) are compounds present in citrus peels and other Rutaceae plants, which exhibit diverse biological activities, including robust antitumor and antioxidant effects. However, the mechanism of PMFs in reversing drug resistance to colon cancer remains unknown. In the present study, we aimed to investigate the potential connection between the aerobic glycolysis-ROS-autophagy signaling axis and the reversal of PTX resistance in colon cancer by PMFs.
MTT Cell viability assay and colony formation assay were used to investigate the effect of PMFs combined with PTX in reversing HCT8/T cell resistance ; the mRNA and protein levels of the target were detected by SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), quantitative real-time fluorescence polymerase chain reaction (qRT-PCR) and Western blot protein immunoblotting (WB); An HCT8/T cell xenograft model was established to investigate the MDR reversal activity of PMFs ; The extracellular acidification rate (ECAR) and the oxygen consumption rate (OCR) were detected to assess the cellular oxygen consumption rate and glycolytic process.
HCT8/T cells demonstrated significant resistance to PTX, up-regulating the expression levels of ABCB1 mRNA, P-gp, LC3-I, and LC3-II protein, and increasing intracellular reactive oxygen species (ROS) content. PMFs mainly contain two active ingredients, nobiletin, and tangeretin, which were able to reverse drug resistance in HCT8/T cells in a concentration-dependent manner. PMFs exhibited high tolerance in the HCT8/T nude mouse model while increasing the sensitivity of PTX-resistant cells and suppressing tumor growth significantly. PMFs combined with PTX reduced extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) in HCT8/T cells. Additionally, PMFs reduced intracellular ROS content, down-regulated the expression levels of autophagy-related proteins LC3-I, LC3-II, Beclin1, and ATG7, and significantly reduced the number of autophagosomes in HCT8/T cells.
The present study demonstrated that PMFs could potentially reverse PTX resistance in colon cancer by regulating the aerobic glycolysis-ROS-autophagy signaling axis, which indicated that PMFs would be potential potentiators for future chemotherapeutic agents in colon cancer.
多甲氧基黄酮（PMFs）是存在于柑橘皮和其他芸香科植物中的化合物，具有多种生物活性，包括强大的抗肿瘤和抗氧化作用。然而，PMFs 逆转结肠癌耐药的机制尚不清楚。本研究旨在探讨有氧糖酵解-ROS-自噬信号轴与 PMFs 逆转结肠癌对紫杉醇（PTX）耐药的潜在联系。
MTT 细胞活力测定和集落形成实验用于研究 PMFs 联合 PTX 逆转 HCT8/T 细胞耐药的作用；通过 SDS-PAGE（十二烷基硫酸钠-聚丙烯酰胺凝胶电泳）、实时荧光定量聚合酶链反应（qRT-PCR）和 Western blot 蛋白印迹（WB）检测靶标 mRNA 和蛋白水平；建立 HCT8/T 细胞异种移植模型，研究 PMFs 的 MDR 逆转活性；检测细胞外酸化率（ECAR）和耗氧率（OCR），评估细胞的耗氧率和糖酵解过程。
HCT8/T 细胞对 PTX 表现出显著的耐药性，上调 ABCB1 mRNA、P-糖蛋白、LC3-I 和 LC3-II 蛋白的表达水平，并增加细胞内活性氧（ROS）含量。PMFs 主要含有两种活性成分，即诺必灵和橘红素，能够以浓度依赖的方式逆转 HCT8/T 细胞的耐药性。PMFs 在 HCT8/T 裸鼠模型中具有高耐受性，同时增加了 PTX 耐药细胞的敏感性并显著抑制肿瘤生长。PMFs 联合 PTX 降低了 HCT8/T 细胞的细胞外酸化率（ECAR）和耗氧率（OCR）。此外，PMFs 降低了细胞内 ROS 含量，下调了自噬相关蛋白 LC3-I、LC3-II、Beclin1 和 ATG7 的表达水平，并显著减少了 HCT8/T 细胞中的自噬体数量。
本研究表明，PMFs 可能通过调节有氧糖酵解-ROS-自噬信号轴来逆转结肠癌对 PTX 的耐药性，这表明 PMFs 将成为未来结肠癌化疗药物的潜在增效剂。
