In Vitro Antitumor Activity And Action Mechanism Of Isoliquiritigenin

Isoliquiritigenin (ISL) is a simple chalcone derivative and found in licorice, it has various biochemical activities such as antioxidative and superoxide scavenging activities, antiplatelet aggregation effect, inhibitory effect on aldose reductase activity and estrogenic properties.though there are some reports on antitumor activity of ISL in recent years, no any reportsut the effect of ISL on the CCRF-CEM Leukemia Cells and prostate Cancer PC-3 cell line.e present study, we examined the growth inhibitory effect of ISL on the CCRF-CEMeukemia Cells, prostate Cancer PC-3 cell line and etc.The growth inhibition of cell proliferation was evaluated by MTT method. Cell cycle distributions were measured by flow cytometric assay (FCM). Laser scanning confocal microscopy and DNA Ladder were used to detected apoptosis. DNA agarose electrophoresis and atomic force microscopy were used to assess oxidative DNA damages.The results showed that:1. ISL significantly inhibited the proliferation of CEM,PC-3 and A549 cells in a dose- and time-dependent manner.The IC₅₀ of CEM,PC-3 and A549 cells exposed to ISL was 18.38gM, 46.8gM and 24.55μM, these results demonstrated that ISL significantly inhibited the proliferation of CEM, PC-3 an A549 cells.2. ISL significantly inhibited the proliferation of CEM,PC-3 cells in a dose- and time- dependent manner.The microscope was used to observe CEM and PC-3 cells exposed to ISL, after exposed to different concentration ISL, the cells can not attach the flask. The results suggest that ISL significantly inhibited the proliferation of CEM and PC-3 cells in a dose- and time-dependent manner.3. ISL restrained the cell cycle progression at G2/M phase in a dose- and time-dependent manner towards CEM cell.Cell cycle distributions were measured by flow cytometric assay, G2/M phase CEM cell after treated with 25μM was 22.84%, G2/M phase CEM cell untreared with ISL was 7.77%. ISL induce fractionlet in PC-3 cell, GO/G1 Phase, S Phaseå’ŒG2/M Phase cells are all reduced.The results demonstrated ISL restrained the the cell cycle progression at G2/M phase in a dose-and time-dependent manner towards CEM cell.4. ISL induced cell apoptosis through CD95 in CEM and PC-3 cellsThe expression rate of CD 95 in CEM cell after treated with 40μM for 24h was 51.47%, this figure is bigger than the CEM cell untreared with ISL 44.62%; The expression rate of CD 147 in CEM cell after treated with 40μM for 24h was 68.74%, this figure is smaller than the CEM cell untreared with ISL 52.34%; The expression rate of CD 95 in PC-3 cell after treated with 100μM for 24h was 31.58%, this figure is bigger than the PC-3 cell untreated with ISL 30.33%; The expression rate of CD 147 in PC-3 cell after treated with 100μM for 24h was4.08%, this figure is bigger than the PC-3 cell untreared with ISL 30.33%. The result suggestsat ISL induces cell apoptosis through CD95 in CEM and PC-3 cells.5. ISL induced apoptosis in CEM and PC-3 cell, but not obvious.Laser scanning confocal microscopy and DNA Ladder are used to detect apoptosis. DNA extracted from CEM and PC-3 cell treated by high concentration of ISL exhibits only dispersion not DNA ladder by electrophoresis. The result suggests that ISL induces apoptosis in CEM and PC-3 cell, but not obvious.6. ISL would induce the oxidative damage of plasmid pBR322 DNA in certain concentration range of Cu²⁺.The results of DNA agarose electrophoresis and atomic force microscopy reveal that only Cu²⁺ and ISL would not induce the oxidative damage ofplasmid pBR322 DNA, but ISL would induce the oxidative damage ofplasmid pBR322 DNA in certain concentration range of Cu²⁺.In summary, ISL significantly inhibited the proliferation of CEM and PC-3 cells in a dose- and time-dependent manner; ISL restrained the cell cycle progression at G2/M phase in a dose-and time-dependent manner towards CEM cell; ISL slightly induced apoptosis in CEM andC-3 cell; ISL would induce the oxidative damage of plasmid pBR322 DNA in certain concentration range of Cu²⁺. The above results offer some scientific references for ISL as the potential anticancer new drug.