Effects Of Butyric Acid, All-trans Retinoic Acid On The Proliferation In Vitro And Expression Of β-catenin, C-myc Of Human Lung Adenocarcinoma A549 Cell Line

Background and aims: Inducers played an important role in the research of the anti-tumor drugs and had a satisfactory prospect。All-trans retinoic acid(ATRA),which was used to therapy APL and got satisfactory effect in clinical work already,was one of the best far-reaching,powerful inducers。But the ill effects related to its unduly clinical dose limited its applications。Therefore,the search for new pattern effective inducers and united application of multi-drugs in low dose was one of the important directions of the research of the anti-tumor drugs。Butyric acid(BA) was a kind of short chain fatty acid,and was proved the effects of growth suppression,induction of cell senescence and apoptosis on many species of tumor cells cultrued in vitro。This experiment was planned to investigate the effects of butyric acid(BA),all-trans retinoic acid(ATRA) on the proliferation and expression ofβ-catenin,c-myc gene of Human lung adenocarcinoma A549 cell line was cultured in vitro and exposed to the two drugs at different concentrations and in the condition of united application。Methods: 1. Groups:To divide the samples into BA groups(with final durg concentration 0.5mM,1mM,2mM,5mM), ATRA groups(with final drug concentration 5×10-6M,1×10-5M,2×10-5M), united group(with final drug concentration BA 1mM＋ATRA 5×10-6M)and control group。2. To investigate the effects of BA and ATRA on the proliferation in vitro of A549 cell with drawing the growth curve。3. To measure the OD and the rate of growth suppression of the A549 cell treated for 72h and 120h with the two drugs by MTT chromatometry。4,To survey the expression of theβ-catenin and c-myc gene by immunohistochemistry assays。Results:1. The Curves of the A549 cell of BA1mM,2mM groups,All ATRA groups and united group were inclined to be flat,having significant lower rate of the cellproliferation and doubling time compared with control group。And they were dependent to the dose。Within them,the cellproliferation rate of the united group was less than the correspondent BA,ATRA groups；BA0.5mM group was similar to the control group(P>0.05)。2. With MTT chromatometry,the values of OD after 72h,120h treatment of BA,ATRA groups were all less than the control group,and varied to the dose；The rate of growth suppression of the united groups was larger than the correspondent BA,ATRA groups (P<0.01)。3. The results of immunohistochemistry assays:(1) AOD of β-cat:Except the BA 0.5mM,all other groups decreased significantly compared with the control group(P<0.01),and the united group decreased more significantly than the correspondent BA group and ATRA group(P<0.01)。(2) AOD of c-myc:Except the BA 0.5mM,all other groups decreased significantly compared with the control group(P<0.01)and the united group decreased more significantly than the correspondent BA group and ATRA group(P<0.01)。BA 5mM group didn't decreased significantly compared with other BA groups (P>0.05)。(3) linear correlation analysis demonstrated:AOD of β-cat showed positive correlation with AOD of c-myc,γ＝0.944,P<0.01。(4) About the positive cells percentage of all BA and ATRA groups:BA 1mM,2mM groups,ATRA 5×10-6M,1×10-5M,2×10-5M groups and united groups decreased significantly compared with the control group(P<0.01),and were dependenct to the dose within them。BA 0.5mM,5mM group and the control group didn't show obvious difference(P>0.05)。linear correlation analysis demonstrated:the percentage of β-cat showed positive correlation with the ratio of c-myc,γ＝0.976,P<0.01。Conclusions: 1. Compared with ATRA,BA had the similar effect of inhibition to the proliferation of the Human lung adenocarcinoma A549 cell line in definite ranges,and were dependent to the dose；When BA and ATRA were used to treat the cells togetherly,they would reinforce effect with each other satisfactorily。2. BA,ATRA would reduce the level of the expression of the Human lung adenocarcinoma A549 cell line in definite ranges,and were dependen...