The effect of intracellular superoxide anion radical on the expression of hcl-2, p53 and c-Ha-ras in Eca-109 esophageal carcinoma cells

Oxygenfreeradicalsarenormalintracellularby--productofcellaerobicmetabolism,whichhavemanybiologicaleffects,andareassociatedwithmanyphysiologicalorpathologicalprocessinorganism'j.Oncogeneareimportantgenesincellproliferation,differentiation,andapoptosis.Theexpressionofoncogenestakespartintheregulationoftheprocessesabove.Inordertodisposethemolecularmechanismofoxygenfreeradicals'biologicaleffects,wehaveobservedtheinfluenceofOiontheexpressionofhcf--2.p53andc--Haarraswhichisassociatedwithapoptosisa…

The effect of intracellular superoxide anion radical on the expression of hcl-2, p53 and c-Ha-ras in Eca-109 esophageal carcinoma cells

Objective: To investigate the effects of intracellular superoxide anion free radical on the expression ofoncogene hcf 2 .p53 and c--Ha--ras. Methods: mammalian vectors expressing sense and anti sense human Mn--SOD(SOD2) were constructed and transfected into Eca 109 esophageal carcinoma cells in order to change intracellularo2 level specifically by increasing or decreasing the intracellular SOD2 level. The expression of oncogene wasdetected via RNA dot blotting and immunohistochemical method. and the alteration of cell cycle was observed viaflowcytometry. Results: The gene expression vectors were transfected into cells. In SOD2 transfected cells,intracellular SOD2 activity increased 5 folds while SOD1 kept unchanged; intracellular O2 was decreased over49%; the expression of hcf 2 was down regulated while the expression of p53 and c Ha ras were up--regulated.Flowcytometry assay showed the number of S--phase cells was reduced. In anti--sense SOD2 trans feeted cells,intracellular SOD2 activity was almost reduced to zero while SOD1 increasesd. which resulted in the increase ofintracellular total SOD activity. and the intracellular of level was decreased over 32 %; the expression of hcf--2.p53 and c Ha ras were all up--regulated. and the alteration of S--phase cells number was not obvious. Conclusion:1. To change intracellular O2; level via trans feeting SOD2 gene into cell is feasible, but it still need furtherimprovement. 2. Alteration of intracellular 02 can affect the expression of hcf--2, p53 and c Hauras in Eca-- 109 cell.and the decrease of intracellular O2, caused by SOD2 gene transfection displayed inhibitory effect on theproliferation of Eca-- 109 esophageal carcinoma cells.