Objective To investigate the effects of poly adenosine diphosphate ribose polymerase (PARP) inhibitor AG014699 on the proliferation of triple negative breast cancer (TNBC) cell line MDA?MB?231.Methods Cell proliferation and cytotoxicity test kit ( CCK?8) was used to detect the proliferation of MDA?MB?231 cells in different concentrations of AG014699 (0.1,1.0,10.0,20.0 and 40.0 mmol／L), DTX (10－9,10－8,10－7,10－6 and 10－5 mol／L) and CBP (10－6,10－5,10－4 and 10－3 mol／L).Flow cytometry was used to detect cell apoptosis and cell cycle distribution.Results The effects of AG01469 at different concentrations (0.1,1.0,10.0,20.0 and 40.0 μmol／L) on proliferation activity of MDA?MB?231 cells were (94.83 ± 3.93)%, ( 79.42 ± 5.52)%, ( 63.75 ± 4.34)%, ( 38.97 ± 8.42)%, ( 29.70 ± 3.35 )%, with statistically significant differences (F＝75.54,P＜0.01,different concentrations pairwise comparison: all P ＜0.05). The efficacy of AG014699 in combination with DTX at different concentrations (( 69.77 ±17.94)%,(58.34± 2.59)%,( 52.81 ± 2.01)%, ( 41.23 ± 3.38)%, ( 24.82 ± 0.73)%) was compared with that of single DTX (( 81.24 ± 11.91)%, ( 85.74 ± 3.10)%, ( 72.74 ± 4.66)%, ( 55.18 ± 3.19)%, (45.95±3.82)%).The differences were statistically significant (t values were －0.923,－11.748,－6.802,－5.199,－9.410,respectively,with P＞0.05 at 10－9 concentration and P＜0.01 at all other concentrations ). The efficacy of AG014699 combined with CBP ((78.33± 2.89)%,( 60.44± 1.95)%,( 50.55± 3.07)%, (12.07± 1.63)%) and single CBP (( 90.00 ± 6.18)%, ( 87.87 ± 2.30)%,( 76.82 ± 3.37)%,( 40.71 ±1.68)%) was compared,and the cell activity was significantly reduced,indicating statistically significant differences ( t values were －1.935,－15.756,－9.981,－21.192, respectively, and P＞0.05 at 10－6 concentration,P＜0.05 at all the other concentrations ).The q value was＞1.15 when AG014699 was combined with 10－3 mmol／L CBP, which showed synergistic effect.When combined with other effective concentrations of DTX or CBP,the q value was between 0.85 and 1.15,showing additive effect.Conclusion PARP inhibitor AG014699 assisted DTX or CBP can inhibit the proliferation of TNBC cell line MDA?MB?231.By means of simple addition or systematic effect,it can inhibit the triple negative breast cancer.

OBJECTIVETo investigate the effects of ischemic postconditioning (IPTC) on the changes of matrix metalloproteinases-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) protein and mRNA levels in rat heart subjected to ischemia/reperfusion, and explore the mechanism by which IPTC protects myocardial interstitium following ischemic/reperfusion (I/R).

METHODSTwenty four healthy male SD rats were randomly divided into 3 groups (n = 8): sham control (SC) group, I/R group and IPTC group. The parameters of left ventricular function including left ventricular systolic pressure (LVSP) and its derivate (±dp/dt) were measured; the amount of myocardial collagen contents was determined by hydroxyproline quantification; the plasma activity of creatine kinase (CK) and lactate dehydrogenase (LDH) was detected; the protien levels of MMP-2 and TIMP-2 was measured by Western blot and the mRNA levels of MMP-2 and TIMP-2 was detected by real-time PCR.

RESULTSThe myocardial collagen contents, left ventricular function and the protein and mRNA levels of TIMP-2 were significantly decreased in I/R group compared with those of SC group, wherease the activities of CK and LDH in the plasma and the protein and mRNA levels of MMP-2 were significantly enhanced in I/R group when compared to SC group. Compared with I/R group, the myocardial collagen contents, left ventricular function and the protein and mRNA levels of TIMP-2 were increased in IPTC group, the activities of CK and LDH in the plasma and the protein and mRNA level of MMP-2 were decreased in IPTC group.

CONCLUSIONThese findings indicate that IPTC has protective effects on myocardial interstitial after the myocardial ischemia/reperfusion injury, and IPTC may exert its cardioprotectve effect via inhibiting MMP-2 and enhancing TIMP-2 expression in cardiac muscle.

Animals ; Collagen ; metabolism ; Creatine Kinase ; metabolism ; Ischemic Postconditioning ; Male ; Matrix Metalloproteinase 2 ; metabolism ; Myocardial Reperfusion Injury ; physiopathology ; Myocardium ; metabolism ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Tissue Inhibitor of Metalloproteinase-2 ; metabolism ; Ventricular Function, Left