The Mechanistic Antitumor Study of Myricanol 5-Fluorobenzyloxy Ether in Human Leukemic Cell Hl-60

Abstract

Aim:The aim of the study was to explore the growth inhibitory effect of myricanol 5-fluorobenzyloxy ether (5FEM) and the underlying mechanism in human leukemic cells HL-60. Materials & methods: 5FEM was obtained by chemical modification of myricanol with fluorobenzyloxy ether at the OH(5) position. The cytotoxicity, cell apoptosis, cell cycle and the expression of key apoptosis-related genes in HL-60 were evaluated. Results & conclusion: 5FEM can significantly inhibited growth of HL-60 cells, increased the G2/M population and upregulated the expression of Bax, Fas, FasL, caspase-9 and p21 and downregulated that of Bcl-2 and survivin. The results enhance our understanding of 5FEM and aid the discovery of novel myricanol derivatives as potential antitumor agents. The incidence and mortality of cancer have been increasing in China [1]. About 4,292,000 new cases of cancer and 2,814,000 cancer-related deaths were estimated in China in 2015 [2]. It was reported that leukemia is the sixth leading cause of cancer death [3].Both genetic and environmental factors have been reported to cause of leukemia [4,5]. Combination of chemotherapy, radiation therapy and bone marrow transplant are involved in treatment of leukemia [6]. But these treatments have limitations because of a high probability of relapse and toxicity. Traditional Chinese medicine and natural plants have been used in the treatment of cancer for thousands of years in China. Owing to its minor side effects and good curative efficacy, the screening of anticancer drugs from traditional Chinese herbal medicine has increased considerably over the past few years [7,8].Myrica rubra (Lour.) Sieb. Et Zucc., a myricaceae Myrica plant, found in China and other Asian countries. Because of its biological properties, the bark of M. rubra is used in Chinese folk medicine [9][10][11]. Myricanol is a cyclic diarylheptanoid isolated from the bark of M. rubra. Diarylheptanoids exhibit various biological activities, including antitumor [12], antiviral [13], antioxidant [14] and anti-inflammatory [15] owing to its unique chemical structure. Our previous studies have shown that myricanol significantly inhibits the proliferation of human lung adenocarcinoma (A549), hepatoma (HepG2) and human promyelocytic leukemia (HL-60) cells. Further, it increased the caspase-3, caspase-9, Bax and p21 expression and decreased the expressions of Bcl-2 at the mRNA and protein levels [16]. Myricanol significantly induced tumor growth inhibitory effects on the xenografts of lung adenocarcinoma A549 by upregulating the expression of Bax and downregulating that of survivin, Bcl-2, VEGF and HIF-1α. The experimentation has indicated that the possible antitumor effects of myricanol are via the mitochondrial apoptosis pathway [17].In order to improve anticancer effect of myricanol, and to further explore the structure-activity relationship of myricanol and discover novel myricanol derivatives as antitumor agents, some novel myricanol derivatives, such as 5-fluorobenzyloxy ether (5FEM), myricanol 5-chlorobe...

Myricanol 5-fluorobenzyloxy ether regulation of survivin pathway inhibits human lung adenocarcinoma A549 cells growth in vitro

“…In the anti-tumor screening of myricanol derivatives, we also used human lung fibroblast 1 (HLF1) as an evaluation of normal cytotoxicity. The results showed that 5FEM was found to have more antitumour activity and low toxicity to HLF1 than that of myricanol and other derivatives [20].…”

“…5-FEM (98.2% purity, batch number: 20170628) was prepared as previously described [20], Myricanol was added to acetone in a round-bottom flask, and stirred until dissolved. K 2 CO 3 was added, and then 4-fluorine benzyl bromide was added in the absence of light at room temperature.…”

“…A549-Homo BIRC5 cells were pretreated with different 5FEM (2.5, 5.0, and 10.0 μM), YM155 (10 nM), or vehicle concentrations (0.1% DMSO) for 48 h. The total protein was extracted as previously described, [20] and equal amounts of cellular protein (30 μg) were separated through electrophoresis and then transferred to a nitrocellulose membrane by using an electrotransfer method.…”

“…Through a series of experiments, we observed that the novel myricanol derivatives with stronger antitumor activity and low toxicity to normal cells. As a result, 5-Fluorobenzyloxy ether (5FEM) is more potent than myricanol and other derivatives [20].…”