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.
ObjectiveTo explore the methods of separation， culture， and identification of breast cancer stromal fibroblasts (BCSFs), which could build up a good basis for the further research of function. MethodsBreast cancer tissues were obtained during breast cancer operation， and were cut into pieces with size of 1 mm×1 mm×1 mm under aseptic conditions， then the pieces of the tissues were digested by collagenase Ⅰ and hyaluronidase. Finally the cells separated from the tissues incubated at 37 ℃ with 5% CO2 and 95% air humidified incubator. Morphological characteristics of the fibroblasts were observed under light microscope. The certain proteins were examined by immunohistochemistry （using CK， Vimentin， α-SMA, and TE-7 antibody） and flow cytometric analysis (CD34 and CD45). ResultsThe separated cells begin to attach to the wall of flask within 24 h and reached almost confluency in about 7 d to 10 d . According to identification, the successful rate of separation and culture of BCSFs was 90%（18/20）, and the characteristics of cells showed that morphological characteristics of the fibroblasts was flat spindle， rich cytoplasm, and a flat ovoid cystic nuclear. The fibroblasts in breast cancer tissues showed negative staining for cytokeratin， positive staining for vimentin， alpha-smooth muscle actin, and TE-7， and negative for CD34 and CD45 by flow cytometric analysis. ConclusionsThe fibroblasts in breast cancer tissues could be easily obtained by tissues cuting combined enzyme digestion and rocking technology in vitro. The present study provide an experimental foundation for further studies on fibroblasts in breast cancer.
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.
Objective To investigate the anti-rejection effect and the mechanism of triptolide （TPT） on islet allo- grafts in a murine model. Methods BALB/c mice were used as islet donor. C57BL/6 mice were rendered diabetic by streptozotocin （STZ） injection， and transplanted with islets under the left kidney capsule. The recipients were randomly （method of random digits table） divided into three groups （n=8）. The mice in the treatment groups were injected intrap-eritoneally with TPT at 50 μg/kg （low-dose TPT group， L-TPT group） or 100 μg/kg （high-dose TPT group， H-TPT group） daily in the first 5 days and then on alternate days until 14 days；while the mice in control group were given vehicles （1% tween 80）. Blood glucose after operation were monitored. The grafts were defined as rejection when two consecutive reading of blood glucose＞20 mmol/L. The left kidney of three recipients in each group were resected for pathological examination. The proportion of CD4＋CD25＋Foxp3＋ regulatory T cells in spleen tissues were tested by flow cytometry. Results The median survival time of islet allografts from the control group， L-TPT group， and H-TPT group were 12.6 days （9-16 days）， 21.4 days （14-27 days） ， and 27.6 days （19-34 days）， respectivly. The percentageof CD4＋CD25＋Foxp3＋regulatory T cells in spleen tissues of three groups were （5.2±0.6）%， （12.0±1.3）%， and（15.7±1.8）%， respectivly. Compared with control group， the median survival time of islet transplantation in mice exte-nded and the proportion of CD4＋CD25＋Foxp3＋ regulatory T cells in spleen tissues increased （P＜0.05）. Conclusions TPT could increase the percentage of CD4＋CD25＋Foxp3＋ regulatory T cells， reduce the rejection after islet transplanta-tion， and prolong the survival time of islet transplantation in mice. The immunosuppressive effect of TPT shows a dose-dependent.