Objective To investigate the effect of caveolion-1 on the growth and proliferation in human breastcancer MCF7 cell in vitro and in vivo and approach its mechanisms. Methods The plasmid pCI-neo-cav-1 and its corres-ponding empty vector （pCI-neo） were transfected into MCF7 cell line. The expressions of caveolin-1 and vascular endoth-elial growth factor （VEGF） in transfectants were subsequently confirmed by Western blot analysis. A pair of monoclonal cell lines， MCF7/cav-1 and MCF7/vec， were chose for future studies. The colony formation ability of tumor cells was detected by anchorage-independent growth assay. Xenograft tumor models in nude mice were established. Immunohisto-chemistry was used to characterize Ki-67 and VEGF levels in the tumors tissues. Results Caveolin-1 expression was up-regulated in the MCF7/cav-1 cell as compared with the MCF7/vec cell （P＜0.01） and the MCF7 cell （P＜0.01）. Caveolin-1 overexpression markedly reduced the capacity of the cells to form colonies in soft agar （P＜0.01）. Compared with the MCF7/vec cell， VEGF protein expression reduced in the MCF7/cav-1 cell （P＜0.01）. In vivo experiments in nude mice， the overexpression of caveolin-1 resulted in significant growth inhibition of the xenograft breast tumors. The Ki-67 staining was weak and the VEGF staining was negative by immunohistochemistry that indicated the caveolin-1 inhibited the proliferation in human breast cancer MCF7 cell. Conclusion The caveolin-1 might inhibit the growth and proliferation in human breast cancer MCF7 cell through suppressing activation of VEGF signaling pathway.
Objective To evaluate the effect of neoadjuvant chemotherapy on the expression of CXCR4 in breast cancer and its clinical significance.Methods The clinical data of 59 patients with breast cancer of stage Ⅱ and stage Ⅲ underwent neoadjuvant chemotherapy with paclitaxel plus epirubicin for 3 cycles between April 2005 and March 2009 were retrospectively analyzed. The expression of CXCR4 in the breast cancer tissues before and after neo-adjuvant chemotherapy was examined by immunohistochemistry and its relationship with clinicopathologic factors was analyzed.Results The CXCR4 positive expression was observed in 56 patients with breast cancer (94.9%), but not in corresponding nontumor normal tissues. The expression level of CXCR4 was correlated to lymph nodes metastasis (P=0.019) and breast cancer stage (P=0.040), but it was not correlated to age of patients, tumor size, grade, hormone receptor (ER and PR)， and HER2 status. The expression level of CXCR4 was significantly decreased after neoadjuvant chemotherapy. Decline extent of CXCR4 expression after chemotherapy and CXCR4 expression level were not correlated to the effect of neoadjuvant chemotherapy, while the effect of chemotherapy in patients expressed CXCR4 in cluster distribution was better than that in scattering distribution (P=0.015). Conclusion The decline extent of CXCR4 expression level after paclitaxel combined with epirubicin neoadjuvant chemotherapy is not correlated to the efficacy, but its expressing distribution may be considered as an index to the effect of neoadjuvant chemotherapy.