Department of Otorhinolaryngology, Peking University Shenzhen Hospital, Shenzhen.
Department of Otorhinolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing.
Anticancer Drugs. 2020 Oct;31(9):932-941. doi: 10.1097/CAD.0000000000000920.
Nasopharyngeal carcinoma (NPC) is a malignant tumor which is commonly found in East Asia and Africa. The present clinical treatment of NPC is still mainly based on chemotherapeutics and is prone to drug resistance and adverse reactions. Shikonin has been demonstrated to play the antitumor effect in various cancers. However, the specific effects and related regulatory mechanism of Shikonin in NPC have not been clearly declared yet. Cell viability was valued through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cell proliferation was detected through colony formation assay and Bromodeoxyuridine (BrdU) assay. Hochest 33258 staining was used to value cell apoptosis. Cell migration and invasion were valued through wound healing and transwell invasion assay, respectively. Glucose uptake, lactate release, ATP level and pyruvate kinase M2 isoform (PKM2) activity were measured using corresponding assay kits. Western blotting was used to examine the expression of proteins related to cell proliferation, cell apoptosis, cell migration and the phosphatidylinositol 3 kinase (PI3K)/AKT signal pathway. We found that Shikonin treatment effectively suppressed cell proliferation and induced obvious cell apoptosis compared with the control. Besides, Shikonin treatment suppressed cell migration and invasion effectively. The detection about glycolysis showed that Shikonin treatment suppressed cell glucose uptake, lactate release and ATP level. The activity of PKM2 was also largely inhibited by Shikonin. Further study revealed that the PI3K/AKT signal pathway was inactivated by Shikonin treatment. In addition, the inducer of the PI3K/AKT signal pathway largely abolished the antitumor effect of Shikonin on cell proliferation, cell apoptosis, cell mobility and aerobic glycolysis in NPC cells. Shikonin inhibits growth and invasion of NPC cells through inactivating the PI3K/AKT signal pathway.
鼻咽癌（NPC）是一种常见于东亚和非洲的恶性肿瘤。目前 NPC 的临床治疗仍主要基于化疗，但容易产生耐药性和不良反应。紫草素已被证明在各种癌症中具有抗肿瘤作用。然而，紫草素在 NPC 中的具体作用和相关调节机制尚未明确阐述。通过 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐（MTT）测定法评估细胞活力，通过集落形成测定法和溴脱氧尿苷（BrdU）测定法检测细胞增殖。Hochest 33258 染色用于评估细胞凋亡。通过划痕愈合和 Transwell 侵袭测定法分别评估细胞迁移和侵袭。使用相应的测定试剂盒测量葡萄糖摄取、乳酸释放、ATP 水平和丙酮酸激酶 M2 同工型（PKM2）活性。Western blot 用于检测与细胞增殖、细胞凋亡、细胞迁移和磷脂酰肌醇 3 激酶（PI3K）/AKT 信号通路相关的蛋白质表达。我们发现与对照组相比，紫草素处理可有效抑制细胞增殖并诱导明显的细胞凋亡。此外，紫草素处理可有效抑制细胞迁移和侵袭。糖酵解检测表明，紫草素处理可抑制细胞葡萄糖摄取、乳酸释放和 ATP 水平。PKM2 的活性也被紫草素大大抑制。进一步的研究表明，PI3K/AKT 信号通路被紫草素处理失活。此外，PI3K/AKT 信号通路的诱导剂可大大消除紫草素对 NPC 细胞增殖、细胞凋亡、细胞迁移和有氧糖酵解的抗肿瘤作用。紫草素通过使 PI3K/AKT 信号通路失活来抑制 NPC 细胞的生长和侵袭。
