Colombo Jucimara, Maciel João Marcos Wolf, Ferreira Lívia Carvalho, DA Silva Renato Ferreira, Zuccari Debora Aparecida Pires
Laboratory of Molecular Investigation of Cancer (LIMC), Faculdade de Medicina de São José do Rio Preto (FAMERP), São José do Rio Preto, São Paulo, SP 15090-000, Brazil.
Department of Molecular Biology, Faculdade de Medicina de São José do Rio Preto (FAMERP), São José do Rio Preto, São Paulo, SP 15090-000, Brazil.
Oncol Lett. 2016 Jul;12(1):231-237. doi: 10.3892/ol.2016.4605. Epub 2016 May 18.
Liver cancer is the sixth most commonly occurring cancer globally, and the main histological type is hepatocellular carcinoma. This type of neoplasia has a poor prognosis due to a high rate of recurrence and intrahepatic metastasis, which are closely are closely associated with the angiogenic process. Vascular endothelial growth factor (VEGF), which is under the control of hypoxia inducible factor-1α (HIF-1α), stimulates the proliferation of endothelial cells and increases cell permeability, promoting the growth, spread and metastasis of tumors. Melatonin, the main hormone secreted by the pineal gland, may have a significant role in tumor suppression and has demonstrated antiangiogenic and antimetastatic effects. The aim of the present study was to analyze the cell viability, migration and invasion, as well as the expression of proangiogenic proteins VEGF and HIF-1α, in HepG2 hepatocarcinoma cells, following treatment with melatonin. Cells were cultured and cell viability was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The expression of proangiogenic proteins VEGF and HIF-1α, under conditions of normoxia and hypoxia, was verified using immunocytochemistry and quantified by densitometry. The analysis of the processes of cell migration and invasion was performed in a Boyden chamber. The MTT assay revealed a reduction in cell viability (P=0.018) following treatment with 1 mM melatonin for 24 h. The expression of proangiogenic proteins VEGF and HIF-1α was reduced in cells treated with 1 mM melatonin for 24 h in normoxic (P<0.001) and hypoxic (P<0.001) conditions, compared with the control group and with induced hypoxia alone. The rate of cell migration and invasion was additionally reduced in cells treated with 1 mM melatonin for 48 h when compared with the control group (P=0.496). The results of the present study suggest that melatonin may have an antiproliferative, antiangiogenic and antimetastatic role in hepatocarcinoma cells and may present a novel therapeutic option for the treatment of liver cancer.
肝癌是全球第六大常见癌症，其主要组织学类型为肝细胞癌。由于复发率和肝内转移率较高，这种肿瘤的预后较差，而这两者与血管生成过程密切相关。血管内皮生长因子（VEGF）受缺氧诱导因子-1α（HIF-1α）调控，可刺激内皮细胞增殖并增加细胞通透性，促进肿瘤的生长、扩散和转移。褪黑素是松果体分泌的主要激素，可能在肿瘤抑制中发挥重要作用，并已显示出抗血管生成和抗转移作用。本研究的目的是分析褪黑素处理后HepG2肝癌细胞的细胞活力、迁移和侵袭情况，以及促血管生成蛋白VEGF和HIF-1α的表达。培养细胞并使用3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐（MTT）法研究细胞活力。使用免疫细胞化学验证常氧和缺氧条件下促血管生成蛋白VEGF和HIF-1α的表达，并通过光密度测定法进行定量。在博伊登小室中进行细胞迁移和侵袭过程的分析。MTT法显示，用1 mM褪黑素处理24小时后细胞活力降低（P = 0.018）。与对照组和单独诱导缺氧组相比，在常氧（P < 0.001）和缺氧（P < 0.001）条件下，用1 mM褪黑素处理24小时的细胞中促血管生成蛋白VEGF和HIF-1α的表达降低。与对照组相比，用1 mM褪黑素处理48小时的细胞的细胞迁移和侵袭率也降低（P = 0.496）。本研究结果表明，褪黑素可能在肝癌细胞中具有抗增殖、抗血管生成和抗转移作用，可能为肝癌治疗提供一种新的治疗选择。
