Effect of methanol-ethyl acetate partitioned fractions from on proliferation and apoptosis of human non-small cell lung cancer H1975 cells / 南方医科大学学报

OBJECTIVE@#To investigate the effects of methanol-ethyl acetate partitioned fractions from (MEDS) on the proliferation and apoptosis of human non-small cell lung cancer H1975 cells.@*METHODS@#The systemic solvent extraction method was used to preliminary separation of the effective fractions in the methanol extract of . The cytotoxicity of each extract (5, 10, 20, 40, and 80 μg/mL) was tested using MTT assay. Colony cloning method was used to assess the effect of different concentrations of methanol-ethyl acetate partitioned fractions from MEDS (5, 10, 20, 40, and 80 μg/ mL) on the proliferation of H1975 cells. Flow cytometric analysis with Annexin V-FITC/PI staining was performed to detect the apoptosis of the cells after treatment with different concentrations of MEDS fractions (10, 20, and 40 μg/mL). Western blotting was used to evaluate the effects of MEDS fractions on the expressions of apoptosis-related proteins Akt, Bax, and Bcl-2. The anti-tumor activity of 100 mg/kg MEDS fractions was tested in a nude mouse model bearing H1975 cell xenografts.@*RESULTS@#MTT assay and colony forming experiment showed that MEDS fractions significantly inhibited the proliferation of H1975 cells in a dose-and time-dependent manner ( < 0.05). The results of flow cytometry showed that MEDS fractions induced obvious apoptosis of H1975 cells in a concentration-dependent manner ( < 0.05). MEDS fractions also significantly decreased the expressions of Bcl-2 and Akt protein and increased the protein expression of Bax ( < 0.05). In the tumor-bearing nude mouse model, MEDS fractions showed potent anti-tumor effects with a low toxicity to affect the body weight and organs of the mice.@*CONCLUSIONS@#The methanol-ethyl acetate partitioned fractions from MEDS show potent anti-tumor activity both and , suggesting their value as promising therapeutic agents against lung cancer.

Effect of anacardic acid, a Hsp90 inhibitor, on proliferation, invasion and migration of breast cancer MDA-MB-231 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the effect of the Hsp90 inhibitor anacardic acid on cell proliferation, invasion and migration of breast cancer MDA-MB-231 cells.</p><p><b>METHODS</b>The inhibitory effect of anacardic acid on Hsp90 was assessed with in vitro ATPase inhibition assay and ATP-sepharose binding assay. MTT assay was used to detect the growth inhibition induced by anacardic acid in MDA-MB-231 cells. Transwell assays were used to evaluate MDA-MB-231 cell invasion and migration. Western blotting was performed to assess the effect of anacardic acid in triggering the degradation of MMP-9, TIMP-1, Hsp90, and Hsp70.</p><p><b>RESULTS</b>Anacardic acid exhibited a modest activity of ATPase inhibition with an IC50 value of 82.5 µmol/L. Anacardic acid significantly suppressed the proliferation of MDA-MB-231 cells in a dose-dependent manner (IC50 value of 29.3 µmol/L). Treatment with 12.5, 25, and 50 µmol/L anacardic acid for 36 h caused inhibition of cell invasion by 23.6%, 56.6%, and 67.0% in MDA-MB-231 cells, respectively (P<0.05), and anacardic acid treatment for 24 h inhibited the cell migration by 30.0%, 45.5%, and 77.5%, respectively (P<0.05). Anacardic acid dose-dependently induced MMP-9 degradation, but did not obviously affect Hsp90 or Hsp70 expressions.</p><p><b>CONCLUSION</b>Anacardic acid can significantly inhibit the proliferation, invasion, and migration of MDA-MB-231 cells, the mechanism of which may involve the inhibition of Hsp90 ATPse activity and down-regulation of MMP-9 expression.</p>

Transglycosylation of neolignans by enzymatic synthesis and evaluation of their antitumor activity / 南方医科大学学报

<p><b>OBJECTIVE</b>To improve the water solubility and biological activity of neoligans (magnolol and honokiol) and test the antitumor activity of the modified compounds.</p><p><b>METHODS</b>The glycosylated products of magnolol and honokiol were obtained by enzymatic synthesis using a UDP-glycosyltransferase (YjiC) from Bacillus. The products were characterized by high-performance liquid chromatography (HPLC), liquid chromatography-mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR) analysis. MTT assay was used to detect the growth inhibition of 4 human cancer cell lines induced by the compounds.</p><p><b>RESULTS</b>We obtained two glucosides of neolignans (magnolol and honokiol) for the first time by enzymatic synthesis using a UDP-glycosyltransferase. Based on the spectroscopic data, the glucosides were identified as magnolol-2- O-β-D-glucopyranoside (1) and honokiol-4'-O-β-D-glucopyranoside (2). Compounds 1-4 exhibited moderate anti-proliferative activities against the 4 human cancer cell lines, with IC50 values ranging from 9.41 to 111.21 µmol/L.</p><p><b>CONCLUSION</b>The glycoslated products show enhanced water solubility and drug sensitivity against SMMC7721 cells, suggesting their value as potential therapeutic drugs.</p>

3-bromopyruvate enhances cisplatin sensitivity of hepatocellular carcinoma cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of 3-bromopyruvate (3-BP) in sensitizing hepatocellular carcinoma cells to cisplatin-induced apoptosis and its possible mechanism.</p><p><b>METHODS</b>The growth inhibition of HepG2 and SMMC7721 cells following exposures to different concentrations of 3-BP and cisplatin was measured by MTT assay. The apoptosis of cells treated with 100 µmol/L 3-BP with or without 8 µmol/L cisplatin was assessed using flow cytometry with PI staining, and the activity of caspase-3 and intracellular ATP level were detected using commercial detection kits; the expression of XIAP and PARP was analyzed using Western blotting.</p><p><b>RESULTS</b>3-BP produced obvious inhibitory effects on HepG2 and SMMC7721 cells at the concentrations of 50-400 µmol/L with IC50 values of 238.9∓13.9 µmol/L and 278.7∓11.7 µmol/L for a 48-h treatment, respectively. Cisplatin also inhibited the growth of HepG2 and SMMC7721 cells at the concentrations of 2-32 µmol/L, with IC50 values of 16.4∓0.9 µmol/L and 20.9∓1.8 µmol/L after a 48-h treatment, respectively. Treatment with 100 µmol/L 3-BP combined with 8 µmol/L cisplatin for 48 h resulted in a growth inhibition rate of (60.6∓2.2)% in HepG2 cells and (56.8∓2.3)% in SMMC7721 cells, which were significantly higher than those in cells treated with 3-BP or cisplatin alone. The combined treatment for 48 h induced an apoptotic rate of (51.1∓4.3)% in HepG2 cells and (46.5∓3.9)% in SMMC7721 cells, which were also markedly higher than those in cells with 3-BP or cisplatin treatment alone.</p><p><b>CONCLUSION</b>3-BP can sensitize HepG2 and SMMC7721 cells to cisplatin-induced apoptosis possibly by causing intracellular ATP deficiency, down-regulating XIAP, and increasing caspase-3 activity.</p>