Yoshimoto Toshiaki, Morine Yuji, Takasu Chie, Feng Rui, Ikemoto Tetsuya, Yoshikawa Kozo, Iwahashi Syuichi, Saito Yu, Kashihara Hideya, Akutagawa Masatake, Emoto Takahiro, Kinouchi Yosuke, Shimada Mitsuo
Department of Surgery Tokushima University Graduate School Tokushima Japan.
Graduate School of Technology, Industrial and Social Sciences Tokushima University Tokushima Japan.
Ann Gastroenterol Surg. 2018 Jan 11;2(2):154-161. doi: 10.1002/ags3.12055. eCollection 2018 Mar.
Light emitting-diodes (LED) have various effects on living organisms and recent studies have shown the efficacy of visible light irradiation from LED for anticancer therapies. However, the mechanism of LED's effects on cancer cells remains unclear. The aim of the present study was to investigate the effects of LED on colon cancer cell lines and the role of photoreceptor Opsin 3 (Opn3) on LED irradiation in vitro.
Human colon cancer cells (HT-29 or HCT-116) were seeded onto laboratory dishes and irradiated with 465-nm LED at 30 mW/cm for 30 minutes. Cell Counting Kit-8 was used to measure cell viability, and apoptosis and caspase 3/8 expression were evaluated by AnnexinV/PI and reverse transcription-polymerase chain reaction (RT-PCR), respectively. Autophagy and expression of LC-3 and beclin-1 were also evaluated by autophagy assays, RT-PCR and Western blotting. We further tested Opn3 knockdown by Opn3 siRNA and the G G-protein inhibitor NF023 in these assays.
Viability of HT-29 and HCT-116 cells was lower in 465-nm LED-irradiated cultures than in control cultures. LC-3 and beclin-1 expressions were significantly higher in LED-irradiated cultures, and autophagosomes were detected in irradiated cells. The reductive effect of cancer cell viability following blue LED irradiation was reversed by Opn3 knockdown or NF023 treatment. Furthermore, increased LC-3 and beclin-1 expression that resulted from blue LED irradiation was suppressed by Opn3 knockdown or NF023 treatment.
Blue LED irradiation suppressed the growth of colon cancer cells and Opn3 may play an important role as a photoreceptor.
发光二极管（LED）对生物体具有多种影响，近期研究表明LED发出的可见光照射在抗癌治疗中具有疗效。然而，LED对癌细胞的作用机制仍不清楚。本研究的目的是在体外研究LED对结肠癌细胞系的影响以及光感受器视蛋白3（Opn3）在LED照射中的作用。
将人结肠癌细胞（HT-29或HCT-116）接种到培养皿中，用465纳米的LED以30毫瓦/平方厘米的强度照射30分钟。使用细胞计数试剂盒-8测量细胞活力，分别通过膜联蛋白V/碘化丙啶和逆转录-聚合酶链反应（RT-PCR）评估细胞凋亡和半胱天冬酶3/8的表达。还通过自噬检测、RT-PCR和蛋白质免疫印迹法评估自噬以及LC-3和贝克林1的表达。在这些检测中，我们进一步通过Opn3小干扰RNA和G蛋白抑制剂NF023测试了Opn3基因敲低情况。
465纳米LED照射培养的HT-29和HCT-116细胞的活力低于对照培养的细胞。LED照射培养的细胞中LC-3和贝克林1的表达显著更高，并且在照射的细胞中检测到自噬体。Opn3基因敲低或NF023处理可逆转蓝色LED照射后癌细胞活力的降低效应。此外，Opn3基因敲低或NF023处理可抑制蓝色LED照射导致的LC-3和贝克林1表达增加。
蓝色LED照射可抑制结肠癌细胞的生长，Opn3可能作为光感受器发挥重要作用。
