Ketkaew Yuwaporn, Osathanon Thanaphum, Pavasant Prasit, Sooampon Sireerat
Interdepartmental Program of Pharmacology, Graduate School, Chulalongkorn University, Bangkok, Thailand.
Department of Anatomy, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.
Arch Oral Biol. 2017 Feb;74:69-74. doi: 10.1016/j.archoralbio.2016.11.010. Epub 2016 Nov 15.
Cancer stem cells contribute to tumor recurrence, and a hypoxic environment is critical for maintaining cancer stem cells. Apigenin is a natural product with anticancer activity. However, the effect of apigenin on cancer stem cells remains unclear. Our aim was to investigate the effect of apigenin on cancer stem cell marker expression in head and neck squamous cell carcinoma cells under hypoxia.
We used three head and neck squamous cell carcinoma cell lines; HN-8, HN-30, and HSC-3. The mRNA expression of cancer stem cell markers was determined by semiquantitative RT-PCR and Real-time PCR. The cytotoxic effect of apigenin was determined by MTT colorimetric assay. Flow cytometry was used to reveal the number of cells expressing cancer stem cell surface markers.
HN-30 cells, a cancer cell line from the pharynx, showed the greatest response to hypoxia by increasing their expression of CD44, CD105, NANOG, OCT-4, REX-1, and VEGF. Apigenin significantly decreased HN-30 cell viability in dose- and time-dependent manners. In addition, 40μM apigenin significantly down-regulated the mRNA expression of CD44, NANOG, and CD105. Consistent with these results, the hypoxia-induced increase in CD44 cells, CD105 cells, and STRO-1 cells was significantly abolished by apigenin.
Apigenin suppresses cancer stem cell marker expression and the number of cells expressing cell surface markers under hypoxia.
癌症干细胞促成肿瘤复发，而缺氧环境对维持癌症干细胞至关重要。芹菜素是一种具有抗癌活性的天然产物。然而，芹菜素对癌症干细胞的作用仍不清楚。我们的目的是研究芹菜素对缺氧条件下头颈鳞状细胞癌细胞中癌症干细胞标志物表达的影响。
我们使用了三种头颈鳞状细胞癌细胞系；HN - 8、HN - 30和HSC - 3。通过半定量逆转录聚合酶链反应（RT - PCR）和实时定量PCR测定癌症干细胞标志物的mRNA表达。通过MTT比色法测定芹菜素的细胞毒性作用。采用流式细胞术检测表达癌症干细胞表面标志物的细胞数量。
HN - 30细胞系（一种来自咽部的癌细胞系）对缺氧表现出最大反应，其CD44、CD105、NANOG、OCT - 4、REX - 1和VEGF的表达增加。芹菜素以剂量和时间依赖性方式显著降低HN - 30细胞活力。此外，40μM芹菜素显著下调CD44、NANOG和CD105的mRNA表达。与这些结果一致，芹菜素显著消除了缺氧诱导的CD44阳性细胞、CD105阳性细胞和STRO - 1阳性细胞数量的增加。
芹菜素在缺氧条件下抑制癌症干细胞标志物表达以及表达细胞表面标志物的细胞数量。
