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Background: The current randomized, controlled, multicenter clinical trial was conducted to investigate the efficacy of concurrent neoadjuvant chemotherapy (NCT) and estrogen deprivation in patients with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer., Methods: Eligible patients with AJCC stage IIB to stage IIIC, ER-positive, HER2-negative breast cancer were enrolled and randomly assigned to receive NCT with or without estrogen deprivation. The primary endpoint was the objective response rate (ORR)., Results: A total of 249 patients were assigned to either neoadjuvant chemoendocrine therapy (NCET) (125 patients) or the NCT group (124 patients). In the intention-to-treat analysis, the ORR was found to be significantly higher in the NCET group compared with the NCT group (84.8% vs 72.6%; odds ratio, 2.11 [95% CI, 1.13-3.95; P = .02). The efficacy of NCET was more prominent in tumors with a higher Ki-67 index (>20%), with an ORR of 91.2% reported in the NCET group versus 68.7% in the NCT group (P = .001). The pathologic complete response and pathological response rates did not differ significantly between the 2 groups. Although there was no significant difference with regard to progression-free survival (PFS) between the 2 groups (P = .188), patients with a higher baseline Ki-67 index appeared to derive a greater PFS benefit from NCET (2-year PFS rate of 91.5% in the NCET group vs 76.5% in the NCT group; P = .058). Adding endocrine agents to NCT did not result in significant differences in adverse events (grade 3 or 4; graded according to National Cancer Institute Common Terminology Criteria for Adverse Events [version 3.0]) between the 2 groups., Conclusions: The addition of estrogen deprivation to NCT appears to improve the clinical response in patients with ER-positive, HER2-negative breast cancer, especially for those individuals with a higher Ki-67 index. Patients with a higher Ki-67 index might derive more PFS benefit from concurrent neoadjuvant treatment., (© 2019 American Cancer Society.)

Purpose: The study was to estimate the likelihood of axillary downstaging and to identify the factors predicting a pathologically node negative status after neoadjuvant chemotherapy (NAC) with or without trastuzumab in HER2-positive breast cancer., Methods: Patients with HER2-positive, stage IIa-IIIc breast cancer were enrolled. Axillary status was evaluated by palpation and fine needle aspiration (FNA) before NAC. All patients received 4-6 cycles of PCrb (paclitaxel 80 mg/m2 and carboplatin AUC = 2 d1, 8, and 15 of a 28-day cycle, or paclitaxel 175 mg/m2 and carboplatin AUC = 6 every-3-week) and were non-randomly administered trastuzumab (2 mg/kg weekly or 6 mg/kg every-3-week) or not. After NAC, each patient underwent standard axillary lymph node dissection and breast-conserving surgery or mastectomy. And some patients received sentinel lymph node biopsy (SLNB) before axillary dissection., Results: Between November-2007 and June-2013, 255 patients were enrolled. Of them, 157 were confirmed as axillary node positive by FNA (group-A) and 98 as axillary node negative either by FNA or impalpable (group-B). After axillary dissection, the overall pathologically node negative rates (pNNR) were 52.9% in group-A and 69.4% in group-B. The ER-poor/HER2-positive subtype acquired the highest pNNR (79.6% in group-A and 87.9% in group-B, respectively) and the lowest rate of residual with ≥4 nodes involvement (1.9% and 3%, respectively) after PCrb plus trastuzumab. In multivariate analysis, trastuzumab added and ER-poor status were independent factors in predicting a higher pNNR in HER2-positive breast cancer. Forty-six tested patients showed that the ER-poor/HER2-positive subtype acquired a considerable high pNNR and axillary status with SLNB was well macthed with the axillary dissection., Conclusions: ER-poor/HER2-positive subtype of breast cancer is a potential candidate for undergoing sentinel lymph node biopsy instead of regional node dissection for accurate axillary evaluation after effective downstaging by neoadjuvant chemo-trastuzumab therapy.

Background: PA-MSHA, a genetically engineered Pseudomonas aeruginosa (PA) strain, is currently under investigation as a new anti-cancer drug. It can induce cell cycle arrest and apoptosis in different human cancer cells, including hormone receptor negative breast cancer cells. However, the underlying mechanism of tumor lethality mediated by PA-MSHA remains to be fully investigated., Methods: The effect of PA-MSHA on human hormone receptor negative breast cancer cells was analyzed by morphological measurement, western blot, cell proliferation assay and mouse xenograft model., Results: PA-MSHA was found to induce endoplasmic reticulum (ER) stress in breast cancer cell lines through the IRE1 signaling pathway. Inhibiting autophagy potentiated the cytotoxic effect of PA-MSHA while treating breast cancer cell lines. In mouse xenograft model, PA-MSHA produced more pronounced tumor suppression in mice inoculated with IRE1 gene knockdown. MDA-MB-231HM cells., Conclusions: These findings demonstrated inhibiting autophagy together with PA-MSHA might be a promising therapeutic strategy in treating hormone receptor negative breast cancer cells.

Purpose: The process of metastases involves the dissociation of cells from the primary tumor, penetration into the basement membrane, invasion, and exiting from the vasculature to seed and colonize distant tissues. miR-200a is involved in this multistep metastatic cascade. This study aimed to test the hypothesis that miR-200a promotes metastasis through increased anoikis resistance in breast cancer., Experimental Design: Breast cancer cells transfected with mimic or inhibitor for miR-200a were assayed for anoikis in vitro. miR-200a expression was assessed by quantitative real-time PCR (qRT-PCR). Luciferase assays, colony formation assays, and animal studies were conducted to identify the targets of miR-200a and the mechanism by which it promotes anoikis resistance., Results: We found that overexpression of miR-200a promotes whereas inhibition of miR-200a suppresses anoikis resistance in breast cancer cells. We identified Yes-associated protein 1 (YAP1) as a novel target of miR-200a. Our data showed that targeting of YAP1 by miR-200a resulted in decreased expression of proapoptotic proteins, which leads to anoikis resistance. Overexpression of miR-200a protected tumor cells from anoikis and promoted metastases in vivo. Furthermore, knockdown of YAP1 phenocopied the effects of miR-200a overexpression, whereas restoration of YAP1 in miR-200a overexpressed breast cancer cells reversed the effects of miR-200a on anoikis and metastasis. Remarkably, we found that YAP1 expression was inversely correlated with miR-200a expression in breast cancer clinical specimens, and miR-200a expression was associated with distant metastasis in patients with breast cancer., Conclusions: Our data suggest that miR-200a functions as anoikis suppressor and contributes to metastasis in breast cancer.

Tau is a microtubule-associated protein and expressed in normal breast epithelial cells and breast cancer. Tau expression in breast cancer may be important for chemotherapy optimization. This study is to investigate the expression of Tau in advanced breast cancer and its significance in taxane-containing neoadjuvant chemotherapy. Levels of Tau protein in advanced breast cancer were detected immunohistochemically. The chemotherapeutic efficacy indexes in Tau(-) group, which includes the remission rate, Miller-Payne pathological reactive grade, and pathologic complete response rate, were improved compared with that in Tau(+) group. There was difference in the efficacy indexes among ER+ subgroups but not among ER- patients. In addition, Tau expression was positively correlated (r = 0.32, P < 0.00). In multivariate analysis, when age, clinical stage, postoperative lymph node metastasis, ER, PR, HER2, Ki-67, TP53, or Tau status were included, postoperative lymph node metastasis and Tau-negative status were identified as independent predictors of pathologic complete response. In conclusion, negative Tau protein expression may be an effective predictor for taxane-containing neoadjuvant chemotherapy, especially in ER+ subgroups. Further study on the molecular mechanism and utility of Tau for individualizing adjuvant chemotherapy is warranted.

Background: The purpose of this study was to identify prognostic factors related to recurrence in women treated with breast-conserving surgery (BCS) and to predict the recurrence following breast-conserving therapy (BCT) by constructing a prediction model., Methods: The retrospective analysis included 764 consecutive invasive breast cancer patients treated with BCT in Shanghai Cancer Center between 1995 and 2008. Univariate and multivariate analysis were performed to identify independent risk factors for locoregional recurrence (LRR) and all the recurrence events. Logistic regression was used to construct a recurrence prediction model, which was further evaluated by receiver operating characteristics (ROC) curves., Results: The 5-year locoregional recurrence-free survival (LRRFS) and recurrence-free survival (RFS) rates were 90.8 and 88.4%, respectively. Multivariate analysis revealed 1 independent predictive factor for LRRFS (lymph node, P = .0049) and three independent predictive factors for RFS (lymph node, P = .0036; molecular subtype, P = .0021; histological grade, P = .041). These three variables entered into logistic regression to establish a recurrent prediction model. ROC curve showed that the area under the curve (AUC) of the established model was 0.70 (95% confidence interval: 0.61-0.78). This model could classify patients into "high-risk recurrence" and "low-risk recurrence" groups and could successfully predict their prognosis (P < .00001)., Conclusions: The information of lymph node status, molecular subtype, and grade may help doctors to evaluate recurrence risk of a woman treated with BCT. Our new model might be helpful in clinical practice for recurrence prediction after BCT in Chinese patients, though further validation studies are needed.

Objective: To examine the effect of postoperative pregnancy upon the prognosis of young Chinese breast cancer patients., Methods: Four hundred and thirty-two female unilateral breast cancer patients aged 35 or younger were retrospectively reviewed. Kaplan-Meier analysis and Log Rank test were used for univariate analysis of factors predictive of disease-free survival (DFS) and overall survival (OS). Multivariate analysis was carried out using the Cox proportional hazards model., Results: Eighteen patients were identified to have postoperative pregnancy, including 5 full-term pregnancy and 13 abortions with the earliest pregnancy taking place at Month 17 post-operation. After a median follow-up of 62 months (6 - 237 months), the DFS and OS rates were 72.5% (313/432) and 88.7% (383/432) respectively. On multivariate analysis, postoperative pregnancy, clinical stage and number of pathologically involved axillary lymph node were significantly associated with DFS. And the axillary lymph node status was also predictive of OS. No death occurred in patient with postoperative pregnancy. There was no significant association between postoperative pregnancy and OS., Conclusion: Postoperative pregnancy has no adverse effect upon the prognosis of young breast cancer patients.

To investigate the effects of PA-MSHA (Pseudomonas aeruginosa-mannose sensitive hemagglutinin) on inhibiting proliferation of breast cancer cell lines and to explore its mechanisms of action in human breast cancer cells. MCF-10A, MCF-7, MDA-MB-468, and MDA-MB-231HM cells were treated with PA-MSHA or PA (Heat-killed P. aeruginosa) at different concentrations and different times. Changes of cell super-microstructure were observed by transmission electron microscopy. Cell cycle distribution and apoptosis induced by PA-MSHA were measured by flow cytometry (FCM) with PI staining, ANNEXIN V-FITC staining and Hoechst33258 staining under fluorescence microscopy. Western blot was used to evaluate the expression level of apoptosis-related molecules. A time-dependent and concentration-dependent cytotoxic effect of PA-MSHA was observed in MDA-MB-468 and MDA-MB-231HM cells but not in MCF-10A or MCF-7 cells. The advent of PA-MSHA changed cell morphology, that is to say, increases in autophagosomes, and vacuoles in the cytoplasm could also be observed. FCM with PI staining, ANNEXIN V-FITC and Hoechst33258 staining showed that the different concentrations of PA-MSHA could all induce the apoptosis and G(0)-G(1) cell cycle arrest of breast cancer cells. Cleaved caspase 3, 8, 9, and Fas protein expression levels were strongly associated with an increase in apoptosis of the breast cancer cells. There was a direct relationship with increased concentrations of PA-MSHA but not of PA. Completely different from PA, PA-MSHA may impart antiproliferative effects against breast cancer cells by inducing apoptosis mediated by at least a death receptor-related cell apoptosis signal pathway, and affecting the cell cycle regulation machinery., ((c) 2009 Wiley-Liss, Inc.)

Objective: To identify predictive markers of the long-term outcome for neo-adjuvant chemotherapy (NC) in locally advanced breast cancer (LABC) treated with intravenous vinorelbine (V) and epirubicin (E) combination regimen., Methods: One hundred and nineteen patients with LABC were treated from September 2001 to May 2006. All patients were diagnosed as invasive breast cancer by 14G core needle biopsy and treated with three cycles of VE regimen before the operation. The patients were subjected to surgery and subsequently were given other three cycles of VE or cyclophosphamide+epirubicin+fluorouracil (CEF) regimen according to the clinical responses. Local-regional radiotherapy was applied to all patients after the chemotherapy and followed by hormone-therapy according to hormone receptor status. The impact of clinical, pathological, and immunohistochemical features on disease free survival (DFS) and overall survival (OS) was evaluated., Results: All patients were evaluable for responses: clinical complete response was documented in 27 patients (22.7%), 78 patients (65.5%) obtained partial clinical response. The pathological complete response was found in 22 cases (18.5%). Of the patients, 115 cases (96.6%) were followed-up for a median time of 63.4 months (range, 9-76 months), the 5-year DFS rate and OS rate was 58.7% and 71.3%, respectively. On multivariate analysis, high pre-Ki-67 (P=0.012) and post-Ki-67 expression (P=0.045), no pathological complete response after NC (P=0.034) were associated with the higher risk of disease relapse; high pre-Ki-67 (P=0.017) and post-Ki-67 expression (P=0.001), negative pre-ER (P=0.002) and no pathological complete response after NC (P=0.034) were associated with a shorter survival., Conclusion: Pathological response in primary tumor, pre-Ki-67 and post-Ki-67 expression, pre-ER expression are important predictors of long-term outcome for LABC patients with three cycles of VE regimen before operation.

A novel highly metastatic MDA-MB-231HM cells, derived from MDA-MB-231, was established in our institute. RT-PCR, real-time PCR and Western blot showed that AF1Q gene was differentially expressed between highly metastatic MDA-MB-231HM cells and its parental MDA-MB-231 cells. However, its molecular mechanisms in breast cancer metastasis remain to be characterized. To investigate the effects of AF1Q on the progression of human breast cancer cells, in the present study, recombinant expression plasmid vectors of the human AF1Q gene was transfected into MDA-MB-231 cells. We demonstrated that AF1Q overexpression enhanced the in vitro proliferation and invasive potential of breast cancer cells. Focused microarray analyses showed that 22 genes were differentially expressed between AF1Q transfected cells and its parental counterparts. Integrin alpha3, accompanied by up-regulation of Ets-1 and MMP-2, significantly enhanced the in vitro invasive potential of human breast cancer cells mediated by AF1Q. Estrogen-responsive ring finger protein gene (EFP), also played a role in the enhancement of in vitro proliferation of human breast cancer cells mediated by AF1Q, accompanied by down-regulation of 14-3-3delta. The association was ERalpha independent. These results were further demonstrated by RNA interference (RNAi) experiment in vitro. In in vivo study, we also demonstrated that AF1Q transfected breast cancer cells grew much faster and had more pulmonary metastases than vector-transfected or its parental counterparts. On the contrary, AF1Q knockdown cells grew slower and had less pulmonary metastasis. Similar effects of AF1Q on integrin alpha3, Ets-1, MMP-2, EFP, and 14-3-3delta expression observed in vitro studies were also found in the in vivo study. Taken together, these results provide functional evidences that overexpression of AF1Q leads to a more progression in human breast cancer, at least in part, through regulating the integrin alpha3, Ets-1, MMP-2, EFP, and 14-3-3delta expression.

E-cadherin is a transmembrane glycoprotein which mediates epithelial cell-to-cell adhesion function as a tumor suppressor and frequently loss of expression in a wide spectrum of human cancer. However, recent studies demonstrated that E-cadherin was always over-expressed in inflammatory breast cancer (IBC) specimen and cell lines, which is a clinical extreme malignancy of breast cancer. It is hypothesized that the gain and not the loss of the E-cadherin axis contributes to the IBC unique phenotype. To test this assumption, we generated dominant negative mutant E-cadherin high-expression inflammatory breast cancer cells by introduced dominant negative mutant E-cadherin (H-2kd-E-cad) cDNA into human IBC SUM149 cells. Our studies demonstrated that the ability of invasion of SUM149 cells was significantly inhibited by H-2kd-E-cad via down-regulation of MMP-1 and MMP-9 expression. The underlying signal pathway of MAPK phosphorylated Erk 1/2(P44/42) in H-2kd-E-cad-transfected SUM149 cells was significantly down-regulated compared to parental and mock contrast. Our studies provided further functional evidence as the gain of E-cadherin expression dedicated to the IBC malignant phenotype and the blockage of MAPK/Erk activation maybe a promising therapeutic target.

Introduction: The molecular mechanisms involved in breast cancer metastasis still remain unclear to date. In our previous study, differential expression of peroxiredoxin 6 was found between the highly metastatic MDA-MB-435HM cells and their parental counterparts, MDA-MB-435 cells. In this study, we investigated the effects of peroxiredoxin 6 on the proliferation and metastatic potential of human breast cancer cells and their potential mechanism., Methods: Expression of peroxiredoxin 6 in the highly metastatic MDA-MB-231HM cells was investigated by RT-PCR, real-time PCR and western blot. A recombinant expression plasmid of the human peroxiredoxin 6 gene was constructed and transfected into MDA-MB-231 and MDA-MB-435 cells. The effects of peroxiredoxin 6 on the proliferation and invasion of MDA-MB-231 and MDA-MB-435 cells were investigated by the Cell Counting Kit-8 method, colony-formation assay, adhesion assay, flow cytometry and invasion assay in vitro. miRNA was used to downregulate the expression of peroxiredoxin 6. Genes related to the invasion and metastasis of cancer were determined by RT-PCR, real-time PCR and western blot. The tumorigenicity and spontaneously metastatic capability regulated by peroxiredoxin 6 were determined using an orthotopic xenograft tumor model in athymic mice., Results: Overexpression of peroxiredoxin 6 in MDA-MB-231HM cells compared with their parental counterparts was confirmed. Upregulation of peroxiredoxin 6 enhanced the in vitro proliferation and invasion of breast cancer cells. The enhancement was associated with decreasing levels of tissue inhibitor of matrix metalloproteinase (TIMP)-2 and increasing levels of the urokinase-type plasminogen activator receptor (uPAR), Ets-1 (E26 transformation-specific-1), matrix metalloproteinase (MMP)-9 and RhoC (ras homolog gene family, member C) expression. The results were further demonstrated by RNA interference experiments in vitro. In an in vivo study, we also demonstrated that peroxiredoxin 6-transfected breast cancer cells grew much faster and had more pulmonary metastases than control cells. By contrast, peroxiredoxin 6 knockdown breast cancer cells grew more slowly and had fewer pulmonary metastases. Effects similar to those of peroxiredoxin 6 on the uPAR, Ets-1, MMP-9, RhoC and TIMP-2 expression observed in in vitro studies were found in the in vivo study., Conclusion: Overexpression of peroxiredoxin 6 leads to a more invasive phenotype and metastatic potential in human breast cancer, at least in part, through regulation of the levels of uPAR, Ets-1, MMP-9, RhoC and TIMP-2 expression.

To study the molecular mechanisms underlying breast cancer metastasis, gene expression profile analysis was performed on two well-established breast cancer cell lines with high and low metastatic potentials: MDA-MB-435HM and MDA-MB-435LM. The analysis was conducted using cDNA microarrays containing 8000 genes. Of 60 differentially expressed genes, ALL1-fused gene from chromosome 1q (AF1Q), a putative oncogene not described previously in breast cancer, was identified and found to be over-expressed in MDA-MB-435HM cells compared with MDA-MB-435LM cells. The results indicate that AF1Q may play an important role in breast cancer metastasis. To test this hypothesis, we generated an AF1Q high-expression cell line by stable transfection of AF1Q cDNA into MDA-MB-435LM cells. Results showed that over-expression of AF1Q led to a marked increase in the invasive and metastatic potential of MDA-MB-435LM cells in vitro and in vivo, accompanied by the up-regulation of matrix metalloproteinase-2 (MMP-2), MMP-9, transcription factor Ets-1, and RhoC expression in both mRNA and protein levels. Consistent with this observation, reduced AF1Q expression in MDA-MB-435HM cells by small interfering RNA (siRNA) resulted in a significant decrease in the invasive potential of MDA-MB-435HM cells in vitro and in the protein expression of MMP-2, MMP-9, Ets-1, and RhoC, compared with either parental or non-silencing control cells. These data provide functional evidence that oncogene AF1Q may be a novel mediator of metastasis promotion in human breast cancer through regulation of the MMP pathway and RhoC expression.

Objective: To analyze the relationship between Duffy antigen receptor for chemokines (DARC) and the metastasis potential in human breast cancer. METHODS Breast cancer tissue sections from 75 patients, grouped according to the local lymph node status were examined immunohistochemically for protein level of DARC. Microvessel density (MVD) was counted by endothelial cells immunostained using anti-CD34 antibody., Results: Strong positive DARC immunostaining in lymph node negative and positive groups was detected in 31 cases (81.6%) and 18 cases (48.6%), respectively (P < 0.01). MVD was (35.67 +/- 17.96)/HP and (53.38 +/- 20.29)/HP in DARC strong positive and less positive cases (P < 0.01). In those patients with lung, bone, hepatic distant metastasis (13 cases), 9 cases (69.2%) were DARC less positive, 4 cases (30.8%) were DARC strong positive. The correlation coefficient was -0.412 between DARC expression and MVD and the corresponding value was -0.346 between DARC expression and lymph node status and -0.333 between DARC expression and distant metastasis in breast cancer., Conclusion: DARC may play a negative role in the process of neoangiogenesis, and probably has an association with the lymph node status.

Objective: To study the effects of Duffy antigen receptor for chemokines (DARC) on the tumorigenesis and metastasis of breast cancer., Methods: Human breast cancer cells of the line MDA-MB-435HM with a great potentiality of metastasis were cultured and then divided into 3 groups: MDA-MB-435HM-DARC cell group, to be transfected with pcDNA3/DARC FyB containing human DARC cDNA; MDA-MB-435HM-vect cell group, to be transfected with blank plasmid pcDNA3; and MDA-MB-435HM cell group without transfection. Female BALB/c nude mice were implanted with MDA-MB-435HM cells into the nipple. The size of the implanted cancer was measured once a week. The mice were killed 4, 6, and 8 weeks after the implantation respectively and their lungs were taken out to observe the number of metastatic tumor. Immunohistochemical staining was performed to calculate the microvascular density (MVD). Western blotting was used to detect the matrix metalloproteinase (MMP)-9 protein expression of the lung tissues. ELISA was used to detect the concentrations of the 2 DARC ligands: CNCL8 and CCL2 in the supernatant of culture fluid of the 3 kinds of cells and the metastatic tumors., Results: The expression levels of DARC mRNA and protein of the MDA-MB-435HM cells were 38% those of the MDA-MB-435 cells. The expression levels of CXCL8 and CCL2 of the MDA-MB-435HM-DARC cells were significantly lower than those of the MDA-MB-435HM-vect cells and MDA-MB-435HM cells (both P < 0.05). All mice developed tumor with a tumorigenesis rate of 100%. However, the tumor occurred 17 days after implantation in those mice implanted with MDA-MB-435HM-DARC cells, significantly later then in those implanted with MDA-MB-435HM-vect cells and MDA-MB-435HM cells (9 and 10 days after implantation) the size of tumor in the former group being significantly smaller than those of the 2 latter groups (both P < 0.01). The number of metastatic foci in the lung of the MDA-MB-435HM-DARC group was significantly less than those of the other 2 groups (both P < 0.01). The level of CCI2 of the implanted tumor in the MDA-MB-435HM-DARC group was significantly lower than those of the other 2 groups (both P < 0.01). The MVD of the MDA-MB-435HM-DARC was significantly less than those of the other 2 groups (both P < 0.01) and most of the vessels of the MDA-MB-435HM-DARC group were not newly formed vessels with a diameter < 8 red blood cells. The MMP-9 protein expression levels of the MDA-MB-435HM-vect cells and MDA-MB-435HM-cells were 3.1 and 3.4 times that of the MDA-MB-435HM-DARC group (both P < 0.05)., Conclusion: DARC, a chemokine decoy receptor, inhibits the chemokine-induced angiogenesis, thus inhibiting the growth and lung metastasis of breast cancer.

Objective: To study effects of estrogen receptor beta (ER beta) on the biological behavior of a human breast cancer cell line MDA-MB-435., Methods: Human ER beta cDNA was introduced into MDA-MB-435 cells by stable transfection. Effects of ER beta expression on cell proliferation and invasion were investigated by MTT, flow cytometry and transwell techniques. Cyclin A, cyclin E, cyclin D1, p21, MMPs, Ets-1, VEGF and b-FGF were detected by RT-PCR and/or Western blot or gelatin zymography., Results: ER beta was shown to be able to significantly increase the proliferation and invasion of MDA-MB-435 cells in an estradiol-independent manner. The S phase distribution of the cells with ER beta overexpression was 46.8%, significantly higher than that of wild type (29.9%) and mock transfected cells (27.6%) (P = 0.01). In ER beta transfected cells, the expression of p21 decreased by 33.3% at mRNA level (P = 0.03) and by 47.4% at protein level (P = 0.02), respectively. The expression of MMP-9 increased by 91.3% at mRNA level (P < 0.01) and its activity was up-regulated by 67.3% (P = 0.02). Furthermore, the mRNA and protein levels of Ets-1 increased 62.2% (P = 0.01) and 51.0% (P = 0.01), respectively. No significant difference was observed in the mRNA levels of cyclin A, cyclin E, cyclin D1, MMP-1, MMP-2, MMP-7, VEGF and b-FGF among these cells., Conclusion: ER beta can enhance proliferation and invasion of breast cancer cells. Down-regulation of p21 and up-regulation of MMP-9 and Ets-1 may be involved in its mechanisms.

Twenty-five to thirty percent of patients with node-negative breast cancer are expected to relapse following surgery, therefore great efforts have been made to identify new prognostic markers that could be useful in defining patients for additional therapy. The expression of MMP-2 and MMP-9 has been associated with high potential of metastasis in several human carcinomas including breast cancer. In the present study we examined the prognostic value of immunoreactive MMP-2/MMP-9 protein in 270 consecutive lymph node negative cases who received radical mastectomy or modified radical mastectomy. Among the patients, 211 cases received adjuvant endocrine therapy and/or adjuvant chemotherapy. Using immunohistochemical assay, we found that 56.7% of the resected tumors were positive for MMP-2 whereas 59.6% of the samples were positive for MMP-9. Chi2 test demonstrated a significant direct association between MMP-2 and MMP-9 (p < 0.001); positive immunostaining of MMP-2 was significantly related to higher tumor grade (p < 0.001) and larger tumor size (p = 0.012); positive immunostaining of MMP-9 was significantly related to higher tumor grade (p = 0.002). In univariate analysis, using Cox-proportional hazard model we found MMP-2, MMP-9 and the co-expression of MMPs (MMP2/MMP9) were significantly associated with patients' relapse free survival (p = 0.016, 0.015 and 0.013 respectively) but not overall survival (p = 0.122, 0.320 and 0.091 respectively). Log-rank test also showed that MMP-2, MMP-9 or the co-expression of MMP2/MMP9 was unfavorable prognostic factor for relapse free survival but not overall survival. In subgroup analysis, we found MMPs were more prognostic for patients with no adjuvant treatment than for patients with adjuvant therapy. In multivariate analysis, using Cox-proportional hazard model we found co-expression of MMPs, larger tumor size and higher tumor grade were unfavorable for relapse free survival (p = 0.038, 0.007 and 0.015 for each). We concluded that MMP-2 and MMP-2 are unfavorable prognostic factors in breast cancer patients. They might be potential predictive factor for adjuvant systemic therapy. The co-expression of MMP-2 and MMP-9 has significantly prognostic value in node-negative patients.

Recent studies of ERs in breast cancer have demonstrated the existence of ERbeta in addition to ERalpha. Some clinical data indicated that ERbeta had prognostic value for patient's survival, which suggested that ERbeta plays a key role in breast cancer development and metastasis. To test this hypothesis, we generated an ERbeta high-expression cell line by reintroduced human ERbeta cDNA into MDA-MB-435 cells. We demonstrated that ERbeta exerted multiple tumor-stimulative effects on human breast carcinoma cells both in vivo and in vitro. In in vitro studies, ERbeta was able to increase the proliferation and invasion of MDA-MB-435 cells significantly, while these effects were totally estradiol independent. Also, this stimulation was characterized by downregulation of p21 and upregulation of MMP-9, as well as transcriptional factor Est-1. In in vivo studies, we also demonstrated that ERbeta-transfected MDA-MB-435 cells grew much faster and had more pulmonary metastasis than mock or wild-type cells in nude mice. In ERbeta-transfected MDA-MB-435 xenografts, ERbeta caused significant reduction in p21 protein levels. Similar effects of ERbeta on MMP-9 and Ets-1 expression noted in vitro studies were also observed in the in vivo studies. These in vitro and in vivo studies indicated that ERbeta exerted multiple stimulative effects on breast cancer development and metastasis.

Objective: To study the value of adjuvant tamoxifen (TAM) in premenopausal women with oestrogen receptor (ER)-positive breast cancer who received adjuvant cyclophosphamide, methotrexate and 5-fluorouracil (CMF) polychemotherapy., Methods: Four hundred and two premenopausal ER-positive breast cancer patients who received CMF chemotherapy between January 1990 and December 1999 were retrospectively studied. Disease-free survival (DFS) and overall survival (OS) were used to evaluate the clinical value of TAM therapy. The relationships between nodal status and TAM were also analysed., Results: After a mean of 41 months of follow-up, 43 (13.7%) patients died of breast cancer and 68 (19.9%) patients suffered recurrence. There was a significant difference between TAM and non-TAM treatment groups for DFS (p=0.0058), but no significant difference for OS. For node-negative patients, there was no significant difference between the TAM and non-TAM treatment groups for either DFS or OS. For node-positive patients, the difference between TAM and non-TAM treatment groups was significant for both DFS and OS (p=0.0497 and p=0.0285, respectively)., Conclusion: TAM resulted in additional benefit to premenopausal patients with node-positive ER-positive breast cancer who received the CMF polychemotherapy regimen.