Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Penang, Malaysia.
Department of Pharmacy, Faculty of Pharmacy and Alternative Medicine, The Islamia University of Bahawalpur, Pakistan.
Biomed J. 2021 Dec;44(6):694-708. doi: 10.1016/j.bj.2020.05.015. Epub 2020 May 28.
Pancreatic cancer is one of the most notorious cancers and is known for its highly invasive characteristics, drug resistance, and metastatic progression. Unfortunately, many patients with advanced pancreatic cancer become insensitive towards gemcitabine treatment. Orthosiphon stamineus (O.s) is used widely as a traditional medicine for the treatment of multiple ailments, including cancer in South East Asia. The present in vitro study was designed to investigate the complementary effects of an ethanolic extract of O.s (Et. O.s) or rosmarinic acid in combination with gemcitabine on Panc-1 pancreatic cancer cells.
Cell viability and colony formation assays were used to determine the 50% inhibitory concentration (IC) of Et. O.s, rosmarinic acid, and gemcitabine. Different doses of gemcitabine in combination with Et. O.s or rosmarinic acid were tested against Panc-1 to select the best concentrations which possessed synergistic effects. Elucidation of molecular mechanisms responsible for mediating chemo-sensitivity in Panc-1 was performed using Quantitative Real-time PCR (QPCR), flow cytometry and immunohistochemistry.
Et. O.s was found to significantly sensitise Panc-1 towards gemcitabine by reducing the gene expression of multidrug-resistant protein family (MDR) (MDR-1, MRP-4, and MRP-5) and molecules related to epithelial-mesenchymal transition (ZEB-1 and Snail-1). An induction of the human equilibrate nucleoside transporter-1 (hENT-1) gene was also found in cells treated with Et. O.s-gemcitabine. The Et. O.s-gemcitabine combination induced cellular senescence, cell death and cell cycle arrest in Panc-1. In addition, the inhibition of Notch signalling was demonstrated through the downregulation of Notch 1 intracellular domain in this treatment group. In contrast, rosmarinic acid-gemcitabine combination showed no additional effects on cellular senescence, apoptosis, epithelial mesenchymal transition (EMT) markers, the MRP-4 and MRP-5 multi-drug resistance protein family, hENT-1, and the Notch pathway through Notch 1 intracellular domain.
This study provides valuable insights on the use of Et. O.s to complement gemcitabine in targeting pancreatic cancer in vitro, suggesting its potential use as a novel complementary treatment in pancreatic cancer patients.
胰腺癌是最臭名昭著的癌症之一，以其高度侵袭性、耐药性和转移性进展为特征。不幸的是，许多晚期胰腺癌患者对吉西他滨治疗不敏感。越南肾茶（O.s）被广泛用作治疗东南亚多种疾病的传统药物，包括癌症。本体外研究旨在探讨 O.s 乙醇提取物（Et. O.s）或迷迭香酸与吉西他滨联合应用对 Panc-1 胰腺癌细胞的互补作用。
细胞活力和集落形成试验用于确定 Et. O.s、迷迭香酸和吉西他滨的 50%抑制浓度（IC）。用不同剂量的吉西他滨与 Et. O.s 或迷迭香酸联合作用于 Panc-1，以选择具有协同作用的最佳浓度。使用定量实时 PCR（QPCR）、流式细胞术和免疫组织化学法阐明介导 Panc-1 化疗敏感性的分子机制。
发现 Et. O.s 通过降低多药耐药蛋白家族（MDR）（MDR-1、MRP-4 和 MRP-5）和上皮-间充质转化（ZEB-1 和 Snail-1）相关分子的基因表达，显著增强了 Panc-1 对吉西他滨的敏感性。还发现细胞用 Et. O.s-吉西他滨处理后，人平衡核苷转运蛋白-1（hENT-1）基因被诱导。Et. O.s-吉西他滨联合诱导 Panc-1 细胞衰老、细胞死亡和细胞周期停滞。此外，通过 Notch 1 细胞内结构域在该治疗组中的下调，证明了 Notch 信号通路的抑制。相比之下，迷迭香酸-吉西他滨联合治疗对细胞衰老、细胞凋亡、上皮间质转化（EMT）标志物、MRP-4 和 MRP-5 多药耐药蛋白家族、hENT-1 以及 Notch 途径的 Notch 1 细胞内结构域没有额外的影响。
本研究为在体外靶向胰腺癌中使用 Et. O.s 补充吉西他滨提供了有价值的见解，表明其在胰腺癌患者中的潜在新的补充治疗用途。
