Liu J.,Tianjin Medical University |
Liu J.,Key Laboratory of Breast Cancer Prevention and Therapy of Ministry of Education |
Liu J.,Key Laboratory of Cancer Prevention and Therapy |
Zhou Y.,Tianjin Medical University |
And 20 more authors.
DNA and Cell Biology | Year: 2016
As an inhibitor of TGF-β signaling, SMAD7 was reported to play dual roles in breast cancer development and progression. It inhibited the cancer metastasis by blocking epithelial-mesenchymal transition, however, litter studies focused on its role in other cancer processes. In this study, miR-497 expression was found inversely correlated with SMAD7 expression in breast cancer tissues. Bioinformatics analyses defined a potential miR-497 response element within 3′ untranslated region of SMAD7 that was validated in reporter gene experiments. Enforced miR-497 expression, accompanied with SMAD7 reduction, suppressed MDA-MB-231 and MCF-7 breast cancer cell growth by MTT and invasion assay, and, induced the S phase arrest detected by flow cytometry. Furthermore, upregulated miR-497 expression by mimics treatment significantly suppressed the tumor growth in the orthotopic nude mouse models. Finally, high expression of miR-497 conferred a better prognosis, indicated by Kaplan-Meier test, especially in HER2 overexpression and triple-negative breast cancer (TNBC). Taken together, our results identified the proliferation promoting role of SMAD7 in breast cancer and therefore established the regulations of SMAD7 in breast cancer by miR-497 through a posttranscriptional mechanism. Moreover, miR-497 might be deemed as a novel potential therapeutic target for the HER2 positive and TNBC in future. © Copyright 2016, Mary Ann Liebert, Inc.
Zhang X.,Tianjin Medical University |
Zhang X.,Key Laboratory of Breast Cancer Prevention and Therapy of Ministry of Education |
Zhang X.,Key Laboratory of Cancer Prevention and Therapy in Tianjin |
Zhang S.,Tianjin Medical University |
And 17 more authors.
European Journal of Cancer | Year: 2012
Recent evidence has suggested that breast cancer contains a rare population of cells called cancer stem cells (CSCs), which have an extensive self-renewal ability and contribute to metastasis and therapeutic resistance. This study evaluated the in vitro and in vivo effects of RAD001 (Everolimus) alone or in combination with docetaxel on stem cells from primary breast cancer cells and two breast cancer cell lines (MCF-7 and MDA-MB-231). In In vitro studies, we sorted ESA +CD44 +CD24 -/low cells as stem cells using flow cytometry from primary breast cancer cells, MCF-7 and MDA-MB-231 cell lines. MTT assays were used to quantify the inhibitory effect of the drugs on total cells and stem cells. Apoptosis and the cell cycle distributions of stem cells were examined by flow cytometry. The tumourigenicity of stem cells after treatment was investigated by soft agar colony formation assays. In In vivo studies, the BALB/c mice were injected with MDA-MB-231 stem cells and the different treatments were administered. After necropsy, the expression of Ki67, CD31, AKT1, and phospho-AKT (Thr308) was analysed by immunohistochemistry. In In vitro studies, all three populations of stem cells were resistant to the standard treatment doses of docetaxel compared with total cells treated with the same drug. Treatment with RAD001 resulted in growth inhibition of all stem cells in a dose-dependent manner. An additive growth inhibitory effect of the combination treatment on the three stem cells was observed in in vitro compared with treatment with RAD001 alone (P < 0.001). In addition, an increase in G2/M cell cycle arrest and an increased population of cells in early apoptosis were seen in the combination treatment group compared with either single-agent group (P < 0.01). In vivo, the volumes of the xenograft tumours significantly decreased in RAD001 alone group compared to control group (P = 0.008), and RAD001 plus docetaxel therapy was much more effective at reducing tumour volume in mice compared with either single-agent alone (P < 0.05). Compared with RAD001 alone, the combination of RAD001 and docetaxel reduced the expression of Ki67, CD31, AKT1 and phospho-AKT (Thr308) (P < 0.05). We conclude that the combination treatment of RAD001 and docetaxel can inhibit the growth of stem cells in vitro and in vivo by inhibiting cell proliferation, inducing apoptosis, cell cycle arrest and reducing the expression of Ki67, CD31, AKT1 and phospho-AKT (Thr308). These data indicate that combination treatment with RAD001 and docetaxel may represent an effective therapy for breast cancer. However, further studies are required to evaluate the drug interaction between RAD001 and docetaxel in the clinical setting. © 2011 Elsevier Ltd. All rights reserved.
Liang X.,Tianjin Medical University |
Liang X.,Key Laboratory of Breast Cancer Prevention and Therapy of Ministry of Education |
Liang X.,Key Laboratory of Cancer Prevention and Therapy |
Li D.,Tianjin Medical University |
And 11 more authors.
Tumor Biology | Year: 2013
This study was undertaken to determine the differences in the clinicopathology and survival between synchronous bilateral breast cancer (sBBC) and metachronous bilateral breast cancer (mBBC). Additionally, we analyzed the risk factors for single tumors to develop as sBBC or mBBC. Of the 190 bilateral breast cancer (BBC) cases, 84 cases were sBBC and 106 were mBBC. We defined sBBC as two tumors that developed within 12 months, while mBBC was defined as two tumors that developed over more than 12 months. The peak age of onset of the first mBBC tumors was significantly younger than that of sBBC tumors (p = 0.001). There was a higher concordance rate of ER/ER positivity and PR/PR positivity in the first and second tumors of sBBC than mBBC. The two sBBC breast cancers had relatively similar hormone conditions because of the low rate of ER and PR transformation from positive to negative or vice versa. We determined that patients who presented with extracapsular extension (p = 0.008) and ER positivity (p = 0.001) tend to have synchronous cancers, while patients with 3+ HER2 were more likely to develop metachronous tumors. The prognosis for mBBC was better than that for sBBC when the survival time of mBBC was measured from the initial observation of the first tumors. © 2013 International Society of Oncology and BioMarkers (ISOBM).
Ma Y.,Tianjin Medical University |
Ma Y.,Key Laboratory of Breast Cancer Prevention and Therapy of Ministry of Education |
Ma Y.,Key Laboratory of Cancer Prevention and Therapy in Tianjin |
Hao X.,Tianjin Medical University |
And 8 more authors.
Breast Cancer Research and Treatment | Year: 2012
The purpose of the study was to detect the effect and possible mechanism of human umbilical cord mesenchymal stem cells (hUCMSCs) on the in vitro and in vivo growth of stem cells isolated from primary human breast cancer cells and cell lines MDA-MB-231 and MCF-7. Primary human breast cancer cells and MDA-MB-231 and MCF-7 cells were sorted in vitro using flow cytometry, and the ESA+, CD44+, CD24-/low cells were isolated as breast cancer stem cells (CSCs). The inhibitory effect of hUCMSCs on CSCs was examined using the Cell Counting Kit-8 cell proliferation and soft agar colony formation assay. In vivo tumor inhibition was studied using a severe combined immunodeficient xenograft mouse model transplanted with MDA-MB-231 breast CSCs. The expression of phosphoinositide 3-kinase (PI3K) and AKT was examined in the xenograft tumors using immunohistochemistry. The number of colonies formed by breast CSCs co-cultured with hUCMSCs at the bottom of soft agar was significantly lower than those formed by the control group (P < 0.01). Compared with the control group, the CSCs co-cultured with hUCMSCs showed a higher number of cells in the G2-M phase (P<0.05) and an increased number of apoptotic cells (P < 0.01). The mice in the medium- and high-concentration hUCMSC treatment groups exhibited clearly reduced tumor volume and tumor weight, compared with the control group (P < 0.01). Compared with the saline group, the xenograft tumor tissues from the mice treated with different concentrations of hUCMSCs showed significantly reduced levels of PI3K and AKT proteins (P < 0.001). In conclusion, hUCMSC significantly inhibited the growth of breast CSCs in vitro and in vivo. The underlying mechanism is likely related to cell cycle arrest, induction of tumor cell apoptosis, and suppressed activities of PI3K and AKT protein kinases. © 2012 Springer Science+Business Media, LLC.
Zhang S.,Tianjin Medical University |
Zhang S.,Key Laboratory of Breast Cancer Prevention and Therapy of Ministry of Education |
Zhang S.,Key Laboratory of Cancer Prevention and Therapy in Tianjin |
Zhang C.,Zhengzhou University |
And 8 more authors.
Medical Oncology | Year: 2012
The purpose of this study was to evaluate the efficacy and safety of Zoladex combined with CEF chemotherapy as neoadjuvant therapy in hormone-responsive, premenopausal, operable breast cancer. One hundred and nineteen patients with hormone-responsive, premenopausal, operable breast cancer were enrolled in the study. Zoladex at 3.6 mg was given by subcutaneous injection every 4 weeks for 3 cycles. CEF (cyclophosphamide, 600 mg/m 2, epirubicin, 60-90 mg/m2, and fluorouracil 500 mg/m 2) was administered every 3 weeks for 4 cycles as neoadjuvant therapy. The primary objective was a pathologic complete response (PCR) rate in the breast. Thirty-one patients (26.1%) achieved a clinical complete response, and 76 patients (63.9%) achieved a clinical partial response; the clinical response rate was 90.0%. Fourteen patients (11.8%) achieved a pathologic complete response (T0/Tis, N0), and 20 patients (16.8%) achieved a pathologic complete response (T0/Tis, Nx). When stratified by the clinical lymph node status, the clinical partial response rate in the clinical lymph node negative group was significantly higher than in the clinical lymph node positive group (P = 0.02). When stratified by hormonal status, the clinical partial response rate in the ER and PR + group was significantly better than the ER or PRgroup (P = 0.0471). There were no treatment-related deaths and no grades 3 or 4 toxicity. The most common adverse event was nausea (grade 1 65.5%, grade 2 18.5%), vomiting (grade 1 58.8%, grade 2 13.4%), and alopecia (grade 1 45.4%, grade 2 54.6%). Zoladex combined with CEF chemotherapy was effective as neoadjuvant therapy in hormone-responsive, premenopausal breast cancer. This regimen was particularly effective in the clinical lymph node negative group and in the ER/PR double positive group. (ClinicalTrials.gov number, NCT00488722). © Springer Science+Business Media, LLC 2011.
Zhang X.,Tianjin Medical University |
Zhang X.,Key laboratory of breast cancer prevention and therapy of ministry of education |
Zhang X.,Key laboratory of cancer prevention and therapy in Tianjin |
Li X.-r.,Chinese People's Liberation Army |
And 3 more authors.
Current Cancer Drug Targets | Year: 2013
The PI3K/Akt/mTOR signaling pathway is involved in the inhibition of tumor cell apoptosis, the promotion of cell survival, cell cycle regulation, tumor angiogenesis, invasion, and metastasis and therefore plays an important role in tumorigenesis, tumor growth, patient prognosis, and tumor treatment. Recent studies have identified this signaling pathway in breast cancer, and the PI3K/Akt/mTOR pathway is therefore being considered as a new therapeutic target and a hotspot in breast cancer research. Pre-clinical studies have confirmed that PI3K inhibitors and mTOR inhibitors achieve anticancer effects by targeting different levels of the PI3K/Akt/mTOR signaling pathway. Among the PI3K inhibitors, some molecules target only PI3K, whereas others target both PI3K and mTOR. Currently, researchers tend to focus on molecular targets based on the different PI3K subtypes to achieve more targeted and specific inhibition of the PI3K pathway. However, the clinical efficacy and efficiency of these inhibitors need to be further studied. The mTOR inhibitors target mTORC1 and have become relatively well-developed targeted therapies for the PI3K/AKT/mTOR pathway. Rapamycin derivatives have been studied in Phase II / III clinical trials in breast cancer, and these derivatives achieved positive results in the treatment of metastatic breast cancer when combined with endocrine therapy or HER2-targeted therapies. This review summarizes the activation of the PI3K/AKT/mTOR pathway, its role in breast cancer, and the latest clinical trials of a variety of PI3K and mTOR inhibitors to improve the understanding of the role of these drugs in breast cancer treatment. © 2013 Bentham Science Publishers.