Effects And Correlation Of Survivin And JNK Signal Pathway In Breast Cancer

The Correlation and Expression of Survivin and JNK Signal pathway in Human Breast CarcinomaObjectiveSurvivin is a member of IAP(inhibitors of apoptosis protein) family. It is strcturally unique among mammalian IAPs. In contrast to other IAPs, survivin was observed to be expressed in fetal tissue and most common human cancer, Whereas no survivin transcripts was detected in normal, terminal differentiate d adult tissue. Survivin is to be expressed in the G2/M phase of the cell cycle in a cycle-regulated manner. At the beginning of mitosis, survivin associates with microtubules of the mitotic spindle in a specific and saturable reaction that is regulated by microtubule dynamics. Disruption of survivin- micro- tubule interactions results in loss of survivin's antiapoptosis function and increased caspase-3 activity, a mechanism involved in cell death, during mitosis. These results indicate that survivin may counteract a default induction of apoptosis in G2 / M phase. The overexpressionof survivin in cancer may overcome this apoptotic checkpoint and favor abrrant progression of transformed cells through mitosis. Survivin has a potent anti- apoptosis and involves in mitosis. The overexpression of survivin in tumor tissues is correlated with poor prognosis of the patients. Survivin can be used as a prognostic factor and a new target in tumor targeting therapy.The c-Jun N-termianl kinase (JNK) is a member of the superfamily of MAP kinase.The JNK are encoded by three genes,jink1, ink2 and jnk3, which are differentially spliced to yield four JNK1 isoforms, four JNK2 isoforms and two JNK3 isoforms. An alternatively spliced sequence near the 3'-end of the coding region dictates the p46 and p54 forms of the three distinctjnk gene products. Investigation of JNK has focused on their activation in response to diverse stresses including ultraviolet and gamma radiation, inflammatory cytokines and cytotoxic drugs. The JNK pathway participates in the response of tumor cells to diverse chemotherapeutics. A substantial literatue supports JNK as required elements in development, morphogenesis and cell differentiation and play a role in cell cycle regulation, cell proliferation and trans- formed growth. In the present study, we detected the expression of Survivin, JNK1/2 in breast cancer, and then detected the effects of transfere with Survivin antisense oligonuclertidy on brest cancer call line T47D'growth and apoptosis, the key moleculars of JNK pathway.Methods(1) The expression of Survivin and JNK1/2 were detacted with immunohistochemical staining using anti-Survivin antibody (1:100) and anti-JNK1/2(1:600) in 49 breast cancer, 9 cases of severe atypical hyperplasia, 11 mild atypical hyperplasia and 6 cases of benigh lession and breast cancer cell line T47D.(2) Survivin antisense oligonucleotide-Lipofectamin were transfected to T47D cell, RT-PCR were used to detect the expression of Survivin mRNA and Western blot was used to detact the expression of Survivin protein after transfection.(3) The supression of T47D cell growth after transfection with Survivin ASODN were detected with MTT.(4) The apoptosis of T47D cell growth after transfection with Survivin ASODN were detected with Annexin V-FITC/PI Flow Cytometry.(5) The expression ofMKK7, JNK1/2 and c-Jun of T47D cell after transfection of Survivin ASODN were detected with Western blot.Results(1) Both survivin and JNK 1/2 proteins are highly expressed in breast cancer tissue, the rate of positive expression of Survivin and JNK1/2 are 71.6% and 69.4% respectively, the tendency of the increased of level of expression Survivin and JNK1/2 is: benigh lesions, atypical hyperplasia, ductal breast cancer, which indicates that Survivin and JNK1/2 are expressed in the breast carcer and precanerous tissues, Survivin and JNK1/2 had correlation in breast cancer.(2) Antisense Survivin-Lipofectamincompound efficiently down-regulated Survivin expression(mRNA and protein), its maximal effect was reached at concentration of 400 nmol(3) Survivin ASODN could surpress the growth of T47D cell and enhance the apop- tosis of T47D cell.(4) Survivin ASODN could somewhat down-reluated the expression of the levels of proteins ofMKK7, JNK1/2 and c-Jun.Conclusion(1) Both of the expression of Survivin and JNK1/2 was much higher in breast cancer than in precancerous tissues.(2) Survivin ASODN could down-regulate the expression of Survivin mRNA and protein of breast cancer cell T47D, and supressed the growth of T47D cell, enhanced apotosis of T47D cell.(3) Survivin ASODN could down-regulate the expression of proteins of MMK7,JNK1/2 and c-Jun of T47D cell.