ABSTRACT
Objective To analyse the expression and significance of CD44 variant (CD44v17) in the process of cervical intraepithelial neoplasia (CIN) to cervical cancer,and to explore the relationship of CD44v17 with CIN and cervical cancer.Methods The expressions of CD44v17,matrix metalloproteinase 9 (MMP9) and Ki67 in normal cervical tissue,CIN Ⅰ,Ⅱ,Ⅲ and cervical carcinoma tissues were detected by real-time quantitative RCR.The expressions of CD44v17,MMP9 and Ki67 in human cervical cancer cell lines HeLa and SiHa after transfecting with CD44v17 siRNA were detected,as well.The tumor-bearing nude mice were treated with lentivirus particles of CD44v17,and the influence of CD44v17 siRNA on tumorigenicity in nude mice was analysed.Results The expression level of CD44v17 increased gradually from CIN Ⅰ,Ⅱ,Ⅲ to cervical carcinoma tissues.Compared with normal cervical tissue,the expression levels of CD44v1 7,MMP9 and Ki67 were significantly increased in CIN Ⅱ,Ⅲ and cervical carcinoma tissues (P＜0.05),while no significant difference was found between normal cervical tissue and CIN Ⅰ tissue (P＞0.05).The expression levels of MMP9 and Ki67 in human cervical cancer cell lines HeLa and SiHa were decreased significantly after transfecting with CD44v17 siRNA (P＜0.01).The tumor volume and weight were decreased by treatment with CD44v17 siRNA transfection (P＜0.01),and the tumorigenicity in nude mice was decreased.Conclusion CD44v17 may promote the development of CIN to cervical cancer.It is expected to be an indicator in predicting malignant potential of CIN.
ABSTRACT
Objective To investigate the effect of mitogen-activated protein kinase(MAPK)pathway on the transcriptional expression of mdr1 gene induced by doxorubicin ( DOX)and study the transcription regulation of mdr1 gene.Methods K562 cells were treated with DOX(0.01 μg/ml)with the initial concentration of 0.01 μg/ml for 24 hours,then change the culture media without DOX.K562 cells were cultured until the its status wag recovered.Subsequently the cells were treated with DOX(0.02μg/ml)for 24 hours again.The concentration of DOX was increaged until 0.05 μg/ml by following the protocol above.K562 cells were collected at the concentration of 0.01 μg/ml,0.03μg/ml and 0.05μS/ml DOX.Expression of mdr1 gene were examined by reverse transcription-polymerase chain reaction(RT-PCR).Pglycoprotein(P-gP)wag detected by flow cytometry.Western blot wag performed to detect ERK and P-ERk.K562 cells were pretreated with MAPK inhibitor PD98059 for 1 hour.and then DOX was added.RT-PCR and FCM were used to detect the expression of mdr1 mRNA and P-gp.Results When K562 cells were exposured to DOX.the phosphorylation of ERK wag increaged.the mdr1 gene wag highly expressed as well as its corresponding protein P-gp.When the concentration of DOX was 0.05μg/ml,the expression of mdr1 gene and P-gp were increased over 5 fold.When K562 cells were pretreated with MAPK inhibitor PD98059,the expression of mdr1 gene induced by DOX(the concentration was 0.03 μg/ml and 0.05 μg/m1)was effectively inhibited by(74.1±0.11)%and(70.2±0.14)%respectively.Conclusions DOX could induce the expression of mdr1 gene in K562 cells accompanied by the activation of MAPK/ERK pathway.The block of activation of ERK could inhibit the induced expression of mdr1 gene.