Objective To investigate the expression of stromal cell-derived factor-1 (SDF-1) and its clinical significance in blood plasma of patients with breast tumor. Methods The level of SDF-1 protein was examined by enzyme linked immunosorbent assay (ELISA) in blood plasma of 26 patients with breast benign tumor and 52 patients with breast cancer. Results The SDF-1 protein in blood plasma was detected in both breast benign tumor patients and breast cancer ones. The level of SDF-1 protein in patients with breast cancer was higher than that in ones with breast benign tumor, and there was a statistical difference between them （P=0.000）. In patients with breast cancer, the level of SDF-1 protein in axillary lymph node (ALN) metastasis positive patients was significantly higher than that in ALN metastasis negative ones （P=0.036）. Conclusion The level of SDF-1 protein in blood plasma may be a specific tumor marker. Its level is correlated with lymph node involvement in breast cancer.
【Abstract】Objective Stromal cell-derived factor-1(SDF-1, CXCL12) is a member of the CXC subfamily of chemokines which, through its cognate receptor (CXCR4), plays an important role in tumor invasion and metastasis. This study analyzed quantitatively the expression of SDF-1 and its relation with clinicopathologic feature and clinical outcome in human breast cancer.Methods Expression of SDF-1 mRNA in 8 breast cancer cell lines, an endothelial cell line HECV and a fibroblast cell MRC5 was studied by using RT-PCR. In addition, the expression of SDF-1 was investigated at both protein (immunohistochemistry) and mRNA(real-time PCR) levels in a group of human normal mammary(n=32) and tumour tissues(n=120). Results SDF-1 expression was identified in MRC5, MDA-MB435s, MDA-MB436, MCF7 cell lines, breast tumour and normal tissues. Significantly higher level of SDF-1 was seen in lymph node positive than in lymph node negative tumours (399.00±210.00 vs 0.89±0.47), P=0.048. The level of SDF-1 expression in patients who developed local recurrence or metastasis, or patients who died of breast cancer was higher than in patients who were disease free as well, (670.00±346.00 vs 0.83±0.35), P=0.01. It was most notable that level of SDF-1 was significantly correlated with over survival (P=0.01) and incidence free survival (P=0.035, by Cox proportion analysis).Conclusion SDF-1 is a factor that is expressed in both stromal cells and some breast cancer cells. Its level are correlated with lymph node involvement, prognosis and survival in patients with breast cancer. SDF-1 may therefore have a potential prognostic value in breast cancer.
ObjectiveTo explore effect and mechanism of the carcinoma associated fibroblasts (CAFs) of breast cancer on growth and metastasis of breast cancer induced in nude mice by inoculation of CAFs and breast cancer cells. MethodsBreast cancer cell line of MDA-MB-231 (abbreviated as MDA), CAFs, and normal breast tissue fibroblasts (NFs) of the same breast cancer patient were collected, and mixed with normal saline (NS) or SDF-1 ligand blockers of four nitrogen heterocyclic fourteen alka (AMD3100, abbreviated as AMD) for inoculation of nude mice in vivo. According to the different combination, 36 nude mice were randomly divided into 6 groups:MDA+NS group, NFs+NS group, MDA+NFs+NS group, MDA+NFs+AMD group, MDA+CAFs+AMD group, and MDA+CAFs+NS group. Forty six days after the inoculation and feeding, volume of tumor, metastasis of lymph node, lung or liver were observed. In addition, level of plasma SDF-1 was tested by using ELISA method, and expressions of SDF-1 mRNA and protein in tumor specimens were detected by using real-time PCR and Western blot method respectively. ResultsExcept for NFs+ NS group, implanted tumor could be seen in nude mice of other 5 groups. In MDA+CAFs+NS group, the volume of tumor[(9.092±2.662) cm3], level of plasma SDF-1[(75.25±16.23) ng/L], and expression levels of SDF-1 mRNA (the median level was 14.714) and protein (the median level was 0.673). of tumor tissue were significantly greater or higher than those of the other 5 groups (P < 0.050). In addition, lymph node metastasis were found in 4 mice in MDA+CAFs+NS group, and 2 in MDA+NS group. The tumor metastasis of lung and liver was not found in all nude mice. ConclusionsCAFs can promote growth and lymph node metastasis of breast cancer, whose mechanism is related with SDF-1 secreted by CAFs and SDF-1/CXC chemokine receptor 4 (CXCR4), signal pathway.