icaritin and Osteosarcoma

Topics: Antineoplastic Agents; Apoptosis; ATP Binding Cassette Transporter, Subfamily B; Cell Line, Tumor; Cell Survival; Dose-Response Relationship, Drug; Doxorubicin; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Flavonoids; Gene Expression Regulation, Neoplastic; Humans; Multidrug Resistance-Associated Proteins; Osteosarcoma; Phosphorylation; Rhodamine 123; STAT3 Transcription Factor; Triterpenes

The mechanism for icaritin to improve postmenopausal osteoporosis (PMOP) has not been clarified. The aim of this study was to investigate the role of estrogen receptor α36 (ERα36) in the proliferation promotion and anti-apoptosis effects of icaritin on osteoblasts and the underlying mechanism of downstream signal transduction. The ERα36 knockdown human osteosarcoma MG63 cell model was constructed by transfection of shRNA vector. Cell proliferation was detected by CCK-8, the apoptosis was detected by flow cytometry, and the activation of ERK and AKT signaling pathways was detected by Western blot. The results showed that the effects of icaritin on the proliferation and apoptosis of MG63 cells were significantly decreased after ERα36 knockdown, and icaritin could up-regulate the levels of ERK and AKT phosphorylation in MG63 cells, which could be reduced by ERα36 knockdown. The effect of icaritin on the proliferation of MG63 cells was significantly decreased by pretreating the cells with U0126 (an ERK signaling pathway blocker) and LY294002 (an AKT signaling pathway blocker), respectively. Furthermore, anti-apoptotic effect of icaritin on MG63 cells was significantly decreased after the cells were pretreated with U0126, but not with LY294002. These results suggest that icaritin exerts proliferation promotion and anti-apoptosis effects on osteoblasts through ERα36 and its downstream ERK and AKT signaling pathways.

Topics: Apoptosis; Butadienes; Cell Line, Tumor; Cell Proliferation; Chromones; Flavonoids; Humans; Morpholines; Nitriles; Osteosarcoma; Phosphorylation; Receptors, Estrogen; Signal Transduction; Up-Regulation

To explore the inhibition and molecular mechanism of icaritin (ICT) combined doxorubicin (DOX) on human osteosarcoma MG-63 cells in vitro.. The control group, ICT groups (10, 20, 40, 80, and 160 µmol/L), DOX groups (1, 2, 4, 8, and 16 µg/mL), and combination groups (20 µmol/ L ICT +1 µg/mL DOX, 20 µmol/L ICT +2 µg/mL DOX, 20 µmol/L ICT +4 µg/mL DOX, 40 µmol/L ICT +1 µg/mL DOX, 40 µmol/L ICT +2 µg/mL DOX, 40 µmol/L ICT +4 µg/mL DOX, 80 µmol/L ICT +1 µg/mL DOX, 80 µmol/L ICT +2 µg/mL DOX, 80 µmol/L ICT +4 µg/mL DOX) were set up. Human osteosarcoma MG-63 cells were respectively cultured and their effects on morphological changes were observed using inverted phase contrast microscope after 24-and 48-h intervention. The cell proliferation inhibition rate of each group was de- termined using CCK-8, and IC50 calculated. The MG-63 apoptosis rate was detected using Annexin V-FITC/ PI double dye flow cytometry. Expression levels of bcl-2, caspase-3, and p21 were detected using RT-PCR.. ICT and DOX could obviously inhibit the proliferation of MG-63 cell. Along with ICT concentration increasing from 10 µmol/L to 160 µmol/L, the cell proliferation inhibition rate also increased gradually from 9.67% ± 3.62% to 89.18% ± 9.66%. The IC50 was 46.93 µmol/L and 3.87 µg/mL respectively. ICT and DOX could cause either early or late stage apoptosis, down-regulate Bcl-2 gene expression, and up-regulate gene expressions of Caspase-3 and p21 respectively (P < 0.05). Aforesaid changes were more obviously seen in combination groups than in lCT groups and DOX groups (P < 0.05).. CT combined DOX had additive or synergistic inhibition effect for the proliferation of osteosarcoma MG-63 cells, which might be related with regulating gene expressions of bcl-2, caspase-3, and p21.

Topics: Apoptosis; Bone Neoplasms; Caspase 3; Cell Line, Tumor; Cell Proliferation; Cyclin-Dependent Kinase Inhibitor p21; Down-Regulation; Doxorubicin; Drug Synergism; Flavonoids; Humans; Osteosarcoma; Proto-Oncogene Proteins c-bcl-2

To explore whether icaritin, a prenylflavonoid derivative of the Chinese tonic herb Epimedium, could suppress the proliferation of human osteosarcoma cells in vitro, and to elucidate the mechanisms of the action.. Human osteosarcoma SaOS2 cell line was used in the present study. The proliferation of the cells was examined using MTT assay and immunofluorescence DAPI staining. Cell motility was studied with the scratch assay. Cell apoptosis was determined by Annexin V-FITC and PI double staining using flow cytometry. Western blotting and RT-PCR were used to measure the expression of mRNAs and proteins in the cells.. Icaritin (5-15 μmol/L) suppressed the proliferation of SaOS2 cells in vitro in a dose-dependent manner. Furthermore, the cell motility was significantly decreased after exposure to icaritin. Moreover, icaritin (5 μmol/L) time-dependently induced the apoptosis of SaOS2 cells, markedly suppressed MMP-2 and MMP-9 expression, upregulated caspase-3 and caspase-9 expression, and increased the level of cleaved caspase-3 in the cells. Co-exposure to the caspase-3 inhibitor zVAD-fmk (10 μmol/L) compromised the icaritin-induced caspase-3 expression and apoptosis in SaOS2 cells.. Icaritin suppresses the proliferation of SaOS2 human osteosarcoma cells by increasing apoptosis and downregulating MMP expression.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Bone Neoplasms; Caspase 3; Caspase 9; Caspase Inhibitors; Cell Line, Tumor; Cell Movement; Cell Proliferation; Dose-Response Relationship, Drug; Down-Regulation; Drugs, Chinese Herbal; Flavonoids; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Humans; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Neoplasm Invasiveness; Osteosarcoma; Time Factors