Pereira Débora Lima, Dos Santos Ferreira Ana Carolina, de Faria Giselle Pinto, Kwee Jolie Kiemlian
Departamento de Estomatologia, Hospital AC Camargo, São Paulo, Brazil.
Pathol Oncol Res. 2015 Jan;21(1):103-11. doi: 10.1007/s12253-014-9794-6. Epub 2014 May 18.
Laryngeal squamous cell carcinoma (LSCC) is the most common among several types of head and neck cancers. Current treatments have a poor effect on early and advanced cases, and further investigations for novel agents against LSCCs are desirable. In this study, we elucidate the cytotoxic enhancing effect of arsenic trioxide (As2O3) combined with L-buthionine sulfoximine (BSO) in LSCC. The effect of BSO with As2O3 or Cisplatin (CDDP) on cell viability was examined using 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The reactive oxygen species (ROS) levels, cell cycle, and apoptosis were measured by flow cytometry using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA), propidium iodide (PI) and annexin V/PI. The acidic vacuolar organelles were visualized by fluorescence microscope and quantified using flow cytometry. Neither CDDP nor As2O3 when used alone reduced the cell viability. BSO was found to enhance only As2O3 sensitivity, leading to G2/M arrest and autophagy with no correlation of ROS induction. This result suggests that modulation of glutathione enhances autophagy, which interplays with apoptosis. In this study, we obtained initial preclinical evidence for the potential efficacy of these drugs in a combined therapy protocol.
喉鳞状细胞癌（LSCC）是几种头颈癌中最常见的类型。目前的治疗方法对早期和晚期病例效果不佳，因此需要进一步研究针对LSCC的新型药物。在本研究中，我们阐明了三氧化二砷（As2O3）联合L-丁硫氨酸亚砜胺（BSO）对LSCC的细胞毒性增强作用。使用3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四氮唑溴盐（MTT）检测BSO与As2O3或顺铂（CDDP）对细胞活力的影响。使用2',7'-二氯二氢荧光素二乙酸酯（DCFH-DA）、碘化丙啶（PI）和膜联蛋白V/PI通过流式细胞术测量活性氧（ROS）水平、细胞周期和细胞凋亡。通过荧光显微镜观察酸性液泡细胞器，并使用流式细胞术进行定量。单独使用CDDP或As2O3均未降低细胞活力。发现BSO仅增强As2O3的敏感性，导致G2/M期阻滞和自噬，且与ROS诱导无关。该结果表明，谷胱甘肽的调节增强了自噬，而自噬与细胞凋亡相互作用。在本研究中，我们获得了这些药物在联合治疗方案中潜在疗效的初步临床前证据。
