Effects of melatonin on HIF-1α and VEGF expression and on the invasive properties of hepatocarcinoma cells

Abstract

Abstract. 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.

Human hepatocellular carcinoma: Protection by melatonin

“…From what has been described above, it would be fair to introduce a possible cross-talk between melatonin with COX- Melatonin shows anti-survival and anti-proliferative roles against HCC depending upon its dosage, incubation time and cell type evaluated. Generally, application of endogenous substances for therapeutic purposes in clinical trials will be effective when they are administered at concentrations considerably higher than their physiological rate of secretion (Colombo, Maciel, Ferreira, Da Silva, & Zuccari, 2016). The initial dose for evolving anti-survival activity of melatonin in HepG2 has yet been controversial, 1 mM in one report (Martín-Renedo et al, 2008), but 10 −7 mol/L in another study .…”

“…The initial dose for evolving anti‐survival activity of melatonin in HepG2 has yet been controversial, 1 mM in one report (Martín‐Renedo et al, ), but 10 −7 mol/L in another study (Fan, Sun, Ma, Zhong, & Wei, ). However, there is consensus about application of 1 mM as an appropriate dose for melatonin in targeting HepG2 cell viability (Carbajo‐Pescador et al, , ; Colombo et al, ; Prieto‐Domínguez et al, ), and that 24 hr exposure time has also been identified as a suitable time for incubation of the cells with melatonin (Fan, Sun, Ma, Zhong, & Wei, ). One mllimeter melatonin is also effective for evolving anti‐survival activity in HuH‐7 cells (Prieto‐Domínguez et al, ).…”

“…HepG2 cell viability(Carbajo-Pescador et al, 2009Colombo et al, 2016;Prieto-Domínguez et al, 2016), and that 24 hr exposure time has also been identified as a suitable time for incubation of the cells with melatonin. One mllimeter melatonin is also effective for evolving anti-survival activity in HuH-7 cells(Prieto-Domínguez et al, 2016).…”

Inhibition of VEGF-Induced VEGFR-2 Activation and HUVEC Migration by Melatonin and Other Bioactive Indolic Compounds

“…In fact, melatonin has been proved to decrease VEGF blood levels in advanced cancer patients [41]. Previous studies support that melatonin inhibits VEGF expression by reducing HIF-1α expression or protein concentration in tumor cells [49,51,52,53,54,55,56]. On the other hand, melatonin has been proposed to directly inhibit angiogenesis by inhibiting endothelial cell proliferation via: (i) modulation of P53 and Bax/Bcl-2 expression, blocking the cell cycle and inducing cellular apoptosis respectively; and (ii) modulation of melatonin receptors/ERK1/2/PI3K/AKT/PKC/NF-ĸB pathways [57,58].…”

3D MR Elastography of Hepatocellular Carcinomas as a Potential Biomarker for Predicting Tumor Recurrence

“…6 Increased interstitial fluid pressure is an additional contributing factor to increased tumor stiffness and is closely associated with the invasiveness and metastasis of HCC. 7 Several staging systems based on tumor morphological characteristics and hepatic function are used by surgeons for the prediction of prognosis and the selection of treatments according to the stage. 8 Currently, tumor characteristics mainly rely on imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI).…”