Objective:To establish a senescence model of rat intervertebral disc nucleus pulposus cells .Methods :The nucleus pulposus cells ,which were extracted from rat intervertebral discs and cultured in complete medium ,were set as control group . The senescence model of nucleus pulposus cells in vitro (senescence model group) was established by additional culture for two hours on the basis of control group ,to which tert‐butyl hydroperoxide(t‐BHP) was added with a final concentration of 100μmol/L .The expression levels of senescence associated indexes ,such as caveolin‐1 and beta‐galactosidase (SA‐β‐gal) ,in two groups were assessed by Western blotting ,while the cell viability in two groups was detected by Cell Counting Kit‐8(CCK‐8) proliferation assay .Results :After two hours of t‐BHP function ,the expression levels of caveolin‐1and SA‐β‐gal in senescence model group were significantly higher than those in control group ,while the nucleus pulposus cells proliferation was slower and the cell viability was much lower .Conclusions :The senescence model of nucleus pulposus cells in vitro can be established successfully with the induction of t‐BHP ,and caveolin‐1 induces the senescence of nucleus pulposus cells during the process .

Objective:To evaluate the effect of interferon-αon the expression and activity of transcription factor specificity pro-tein 1(Sp1) in hepatocarcinoma cells .Methods :The effect of interferon-αon the expression and phosphorylation level of Sp1 in hepatocarcinoma cell line M HCC97H were detected by Western blotting .The effect of interferon-α on the activity of Sp1 was analyzed by electrophoretic mobility shift assay (EMSA) .Results :Interferon-α significantly reduced the expression and phos-phorylation level of Sp1 ,and the reducement on phosphorylation was more distinct .Interferon-α also inhibited the activity of Sp1 significantly .Conclusions :Interferon-αinhibits the activity of Sp1 by down regulating the expression and phosphorylation level of Sp1 .Sp1 may be an optional predictor of clinical efficacy of interferon-αon hepatocarcinoma .