Department of Zoology, West Bengal State University, Kolkata, West Bengal, India.
Department of Chemistry, N.S. Mahavidyalaya, Udaipur, Tripura, India.
J Am Nutr Assoc. 2023 Aug;42(6):573-587. doi: 10.1080/27697061.2022.2107583. Epub 2022 Aug 19.
Oral squamous cell carcinoma OSCC) is the predominant type of oral cancer. Its incidence is high in certain geographic regions, and it is correlated with chewing tobacco. Epidermal growth factor receptor (EGFR), induced by tobacco carcinogens, is overexpressed in OSCC, leading to poor prognosis. Thus, EGFR inhibitors are promising agents against OSCC. High cost and toxicity of existing EGFR inhibitors necessitate alternative EGFR-targeted therapy. Here, we tested the antitumor potential of ethyl acetate fraction of an ethnomedicinal tree, stem bark extract (OIEA) in a 4-nitroquinoline-1-oxide (4NQO)-induced oral carcinogenesis model.
OIEA was prepared by solvent extraction method, and subsequently its radical scavenging activities were measured. High-performance liquid chromatography (HPLC) analysis of OIEA was done to identify the constituent active compounds. Hemolytic, trypan blue exclusion, and MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] assays were performed in normal and cancer cells to select an optimum dose of OIEA for antitumor activity study in 4NQO-induced oral cancer in F344 rats. Measurement of tumor volume, weight, and cell count was followed by tumor cell cycle analysis and comet and annexin V/Propidium Iodide (PI) assay. Pro-apoptotic markers were detected by western blot testing. Molecular docking was done to predict the interaction between OIEA active component and EGFR or phosphatidylinositol-3-kinase (PI3K), which was further validated biologically. Finally, hepatic and renal function testing and histopathology were performed.
OIEA reduced tumor burden and increased survivability of the tumor-bearing rats significantly as compared to untreated tumor bearers. HPLC revealed oroxylin A as the predominant bioactive component in OIEA. Molecular docking predicted significant binding between oroxylin A and EGFR as well as PI3K, which was confirmed by western blot analysis of samples. OIEA also ameliorated hepato-, renal- and myelotoxicity induced by 4NQO.
OIEA reduces 4NQO-induced OSCC by modulating the EGFR/PI3K/AKT signaling cascade and also ameliorated toxicity in tumor bearers.
口腔鳞状细胞癌（OSCC）是口腔癌的主要类型。在某些地理区域，其发病率较高，并且与咀嚼烟草有关。烟草致癌物诱导的表皮生长因子受体（EGFR）在 OSCC 中过度表达，导致预后不良。因此，EGFR 抑制剂是治疗 OSCC 的有前途的药物。现有 EGFR 抑制剂的高成本和毒性需要替代的 EGFR 靶向治疗。在这里，我们测试了一种民族药用树的乙酸乙酯提取物（OIEA）在 4-硝基喹啉-1-氧化物（4NQO）诱导的口腔致癌模型中的抗肿瘤潜力。
采用溶剂提取法制备 OIEA，然后测定其自由基清除活性。采用高效液相色谱（HPLC）分析 OIEA，以鉴定其组成的活性化合物。在正常细胞和癌细胞中进行溶血、台盼蓝排除和 MTT [3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四唑溴化物]测定，以选择 OIEA 的最佳剂量用于在 F344 大鼠中进行 4NQO 诱导的口腔癌的抗肿瘤活性研究。测量肿瘤体积、重量和细胞计数，然后进行肿瘤细胞周期分析和彗星和 Annexin V/Propidium Iodide（PI）测定。通过 Western blot 检测检测促凋亡标志物。进行分子对接以预测 OIEA 活性成分与表皮生长因子受体或磷脂酰肌醇-3-激酶（PI3K）之间的相互作用，并用生物学方法进一步验证。最后，进行肝肾功能测试和组织病理学检查。
与未经治疗的肿瘤携带者相比，OIEA 显著降低了肿瘤负担并提高了肿瘤携带者的存活率。HPLC 显示，白杨素 A 是 OIEA 中的主要生物活性成分。分子对接预测白杨素 A 与表皮生长因子受体和 PI3K 之间存在显著结合，这通过对样品的 Western blot 分析得到证实。OIEA 还改善了 4NQO 引起的肝、肾和骨髓毒性。
OIEA 通过调节 EGFR/PI3K/AKT 信号级联来减少 4NQO 诱导的 OSCC，并改善了肿瘤携带者的毒性。
