MK615 decreases RAGE expression and inhibits TAGE-induced proliferation in hepatocellular carcinoma cells.

AIM: To investigate the proliferative effect of advanced glycation end-products (AGEs) and the role of their cellular receptor (RAGE) on hepatocellular carcinoma (HCC) cells, and the inhibitory effects of MK615, an extract from Japanese apricot, against AGEs were also evaluated. METHODS: Two HCC cell lines, HuH7 and HepG2, were used. Expression of RAGE was investigated by polymerase chain reaction, Western blotting, and flow cytometry (FACS). The effect of MK615 on RAGE expression was also evaluated by FACS. The proliferative effects of a control (unglycated bovine serum albumin), glucose-derived AGEs (Glc-AGE), and glyceraldehyde-derived AGEs (Glycer-AGE), and the anti-proliferative effect of MK615 against AGEs, were evaluated using MTT assays. RESULTS: Expression of RAGE was confirmed at both the mRNA and protein levels in both HuH7 and HepG2. FACS revealed that the level of RAGE expression was higher in HuH7 than in HepG2. Treatment with 0.1 µg/mL MK615 decreased the expression level of RAGE from 24.3% to 3.7% in HuH7 and from 6.2% to 4.8% in HepG2. The growth indices for the control, Glc-AGE, and Glycer-AGE were 1.06 ± 0.08, 0.99 ± 0.04, and 1.38 ± 0.05, respectively, in HuH7 (P = 0.037), and were 1.03 ± 0.04, 1.04 ± 0.03, and 1.07 ± 0.05, respectively, in HepG2 (P > 0.05). When the cells were cultured simultaneously with Glycer-AGE and MK615, MK615 abrogated the proliferative effect of Glycer-AGE in HuH7. CONCLUSION: Only Glycer-AGE has a proliferative effect on HuH7, which expresses a higher level of RAGE. MK615 suppresses the proliferative effect of Glycer-AGE on HuH7 by decreasing the expression of RAGE.

New anti-proliferative agent, MK615, from Japanese apricot "Prunus mume" induces striking autophagy in colon cancer cells in vitro.

AIM: To investigate the anti-neoplastic effects of MK615, an extract from the Japanese apricot (Prunus mume), against colon cancer cells. METHODS: Three colon cancer cell lines, SW480, COLO, and WiDr, were cultured with MK615. Growth inhibition was evaluated by cell proliferation assay and killing activity was determined by lactate dehydrogenase assay. Induction of apoptosis was evaluated by annexin V flow cytometry. Morphological changes were studied by light and electron microscopy, and immunofluorescence staining with Atg8. RESULTS: MK615 inhibited growth and lysed SW480, COLO and WiDr cells in a dose-dependent manner. Annexin V flow cytometry showed that MK615 induced apoptosis after 6 h incubation, at which point the occurrence of apoptotic cells was 68.0%, 65.7% and 64.7% for SW480, COLO, and WiDr cells, respectively. Light and electron microscopy, and immunofluorescence staining with Atg8 revealed that MK615 induced massive cytoplasmic vacuoles (autophagosomes) in all three cell lines. CONCLUSION: MK615 has an anti-neoplastic effect against colon cancer cells. The effect may be exerted by induction of apoptosis and autophagy.

New antineoplastic agent, MK615, from UME (a Variety of) Japanese apricot inhibits growth of breast cancer cells in vitro.

MK615 is an extract mixture containing hydrophobic substances from Japanese apricot. In this study, the antineoplastic effects of MK615 against breast cancer cells were investigated. Two breast cancer cell lines, MDA-MB-468 (MDA) and MCF7, were cultured with (600, 300, and 150 mug/mL) or without MK615. After 72 hours of incubation, growth inhibition was evaluated by MTT assay. The cells were then cultured with MK615 (300 mug/mL) and morphological changes were studied by light and electron microscopy. Finally, the mechanism of the antineoplastic effect of MK615 was evaluated by cell cycle and apoptosis assay. MK615 inhibited the growth of MDA and MCF7 in a dose-dependent manner. The percentage growth inhibition of MDA at dosages of 600, 300, and 150 mug/mL was 59.2%, 52.4%, and 23.3%, respectively, and that for MCF7 was 83.5%, 52.7%, and 16.6%, respectively. Morphological changes after MK615 treatment included massive vacuolization in the cytoplasm and apoptotic changes in the nucleus. These changes began to be apparent after at least 6 hours of incubation. Cell cycle analysis showed that MK615 increased the proportion of cells in the G2-M phase in both MDA (7.8-11.7%) and MCF7 (8.1-18.7%), and finally both cell lines became apoptotic. The proportion of apoptotic cells increased with incubation time. MK615 effectively inhibits the growth of breast cancer cells in vitro, possibly by cell cycle modification and apotosis induction. MK615 should be further investigated as a promising anti-breast cancer agent.