Investigation of the apoptosis mechanism induced by lactacystin in prostate cancer cell / 中国医师进修杂志

ABSTRACT

Objective To investigate the relationship between nuclear factor(NF)-κB activity and lactacystin induced prostate cancer cell apoptosis.Methods Two prostate cancer cell were divided into two groupsblank control group treated with culture solution,lactacystin group treated with different concentration of lactacystin(0.5,1.0,2.0,4.0 μ mol/L),the action time were 8,16 and 24 hours.The cell survival rate was measured by MTT assay.NF-κB DNA binding activity was measured by enzyme-linked immunosorbent assay,the expression of NF-κB P65 nuclear protein was detected by Western blot assay,and caspase-3 activity was analyzed by enzyme analysis assay.Results On basal condition,the NF-κ B DNA binding activity was much higher in DU145 cell than that in LNCaP cell(t=4.728,P=0.001).Compared with blank control group,different concentration of lactacystin groups'NF-κ B DNA binding activity in both the LNCaP and DU145 cell were reduced.The expression of NF-κB p65 nuclear protein decreased along with raising of lactacystin concentration in LNCaP cell,but it did not change in DU145 cell.On basal condition,caspase-3activity in DU145 cell was higher than that in LNCaP cell(t=4.519,P=0.001).After lactacystin acting of 24 hours,caspase-3 activity increased along with raising of lactacystin concentration in both the LNCaP and DU145 cell(2.0 μmol/L lactacystin group compared with 1.0 μmol/L lactacystin group,DU145 cell P=0.000,LNCaP cell P=0.000).Conclusions Lactacystin has different killing effects on prostate cancer cell.The mechanism may be related to inducing the apoptosis by down-regulation of NF-κB activity.There may be additional cell survival/death pathway in androgen-independent prostate cancer cell.