| Co-stimulators CD40/CD40L and OX40/OX40L, which belong to TNF/TNFR super family, play an important role in immunology response and have a close relation to serious disorders such as autoimmune disease and cancer. In view of their notable functions, the expression of CD40 OX40 OX40L with associated molecules P53 and VEGF on human breast cancer and their clinical significance were focused on in this study. The effects of CD40L ligation on the growth, the proliferation, cell cycle and cell apoptosis in CD40 positive breast cancer cell lines as well as phenotype were explored. The possible mechanism of CD40 OX40 OX40L in the pathogenesis of breast cancer and CD40 as a potential therapeutic target was assessed. Meantime, OX40L genes encoding human OX40L as well as soluble OX40L were cloned, and then transfected into mouse fibroblast cell line L929 and expressed in E.coli system, respectively. Both bioactivity of the OX40L transgenic cell and recombinant protein were investigated.1. the expressions and clinical significances of CD40 and associated molecules in human breast cancerSurgical biopsy specimens were obtained from 58 patients. The expression of CD40 and associated molecules P53 and VEGF on different types of malignant breast cancer tissues were examined by irnmunohistochernistry. The expression of CD40 on the surface of cancer cells from 20 cases of fresh breast cancer tissues and two cell lines were also analyzed by irnrnunofluorescence technique and flow cytometry. Theexpression of CD40 P53 and VEGF on breast tissues have significant differences from the normal ones nearby the malignant ones (p<0.01). The rates of CD40 positive cell in the 58 cases of biopsy tissues and in the 20 cases of fresh tissues were 37.9% and 50%, respectively. The two cell lines do well express CD40 molecule. Further more, the expression of CD40 has a close correlation to lymph nodule metastasis. There was no relation with skin conglutination and pathological grade. Interestingly, CD40 expression had a positive correlation with P53 expression (r=0.52, p<0.01) while VEGF had not (p>0.05). These results suggested that CD40, P53 and VEGF might have some effect on the pathogenesis of breast, and the expression of CD40 and P53 might be a valuable factor for judgment of prognosis and monitor of lymphonudule metastasis. These data also indicated that P53 status must be under full consideration while CD40 is taken as a target molecule for biological therapy.2. the biological effects of CD40 ligation on human breast cancer cell linesCD40 positive cell lines MDA-MB-231 and MDA-MB-435 showed an obvious inhibition of cell growth and proliferation assessed by 3H-TdR incorporation when these cells were incubated with rhCD40L. Up-regulation of surface molecules such as HLA-DR. FASL.TNFRI were observed by immunofluorescence phenotype and flow cytometry analysis, meanwhile CD44 CD54 on MDA-MB-231 and MDA-MB-435 were highly expressed. An up-regulation of RANTES transcription level was also found by RT-PCR. The data showed that, the CD40 ligation of tumor cells could conduct an antitumor immune responses not only in the phase of ignition but also in the phase of effection, by the way of up-regulating adhesion molecules/co-stimulators / cytokines and meliorating or rectifying T cell clonal anergy. According to this, it can be regarded as an indirect role in antitumor immunity by CD40 ligation.In the present work, incubation in vitro of breast cancer cells with rhCD40L resulted in significant growth inhibition while the changes of cell cycle becameobvious. The numbers of MDA-MB-231 and MDA-MB-435cells entering into G1 phase increased while the numbers into S phase decreased significantly, after rhCD40L activated the cells for 48 72h , respectively. The results of RT-PCR for BCL-XL BAX showed that the ratio of BAX to BCL-XL increased. Since BCL-2 family members accounted for cell survival and growth arrest, the results was in agreement with our earlier research work on B lymphoma cell lines and an earlier report that apop...
|
PDF Full Text Request