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The importance of long noncoding RNA (lncRNA) in tumorigenesis has been supported by increasing evidence in recent years. However, the mechanism linking lncRNA function with cancer progression remains poorly understood. lncRNA LCPAT1 plays a role in lung cancer. However, how it works in breast cancer (BC) is largely unclear. In this study, we found that LCPAT1 was highly expressed in BC tissues and cell lines. High LCPAT1 expression predicted a low survival rate in BC patients. LCPAT1 promoted BC cell proliferation, migration, and invasion while inhibiting apoptosis in vitro. LCPAT1 knockdown suppressed BC growth in vivo and vice versa. LCPAT1 interacted with RBBP4 and recruited it to the MFAP2 (microfibril-associated protein 2) promoter and then activated MFAP2 transcription. Restoration of MFAP2 rescued the effects of LCPAT1 knockdown in BC cells. In sum, LCPAT1 promotes BC progression through recruiting RBBP4 to initiate MFAP2 transcription., Graphical Abstract, Gong et al. demonstrate that LCPAT1 was highly expressed in breast cancer tissues and promoted breast cancer cell proliferation, migration, and invasion while inhibiting apoptosis through recruiting RBBP4 to initiate MFAP2 transcription. Their work illustrates a new mechanism involved in breast cancer progression and suggests that LCPAT1 may be a new therapeutic target.

Background: Lung cancer is the most common cause of death from cancer worldwide and recent studies have revealed that microRNAs play critical roles to regulate lung carcinogenesis. microRNA-129-5p (miR-129-5p) has been reported to regulate cell proliferation and invasion in lung cancer, but its role in lung cancer apoptosis remains unknown. Methods: The expression of miR-129-5p and YWHAB in lung cancer tissues were analyzed from data downloaded from the NCBI Gene Expression Omnibus (GEO) database. Luciferase reporter assay, Western blot and qRT-PCR were used to determine the regulatory effect of miR-129-5p on YWHAB. Cell apoptosis was detected by using the PI/Annexin V Cell Apoptosis Kit. The effect of miR-129-5p and YWHAB on the survival of lung cancer patients was also explored. Results: In this study, by combining the data derived from six GEO database, our results showed that miR-129-5p was downregulated in lung cancer tissues and YWHAB was upregulated in lung cancer patient' serum. A significant negative correlation between miR-129-5p and YWHAB was found in lung cancer tissues. Both the expression of YWHAB and miR-129-5p were associated significantly with prognosis (overall survival) in patients with lung cancer. Overexpression of miR-129-5p promotes VP16-induced lung cancer cell apoptosis and YWHAB was shown to be a direct downstream target of miR-129-5p. Conclusion: Overexpression of expression miR-129-5p contributes to etoposide-induced lung cancer apoptosis by modulating YWHAB.

Objective:Triple negative breast cancer (TNBC) is known to have aggressive clinical course and a high risk of recurrence. Given the lack of effective targeted therapy options, paclitaxel-based chemotherapy is still the primary option for TNBC patients. However, patients who fail to achieve a complete response during neoadjuvant chemotherapy may be mainly due to sensitivity and resistance to chemotherapy. Thus, we concentrated the present research on the role of PGK1 in the sensitivity to paclitaxel treatment and the possible underlying mechanisms in TNBC.Methods:After exposure to paclitaxel, a cell viability analysis was made to investigate the influence of PGK1 silencing on cell death. The effect of PGK1 on apoptosis induced by paclitaxel treatment was examinedin vitroby flow cytometry cell apoptosis assays. Western blotting was performed to examine the impact of PGK1 on paclitaxel-induced apoptosis. The correlation of PGK1 with apoptosis-associated protein X-linked inhibitor of apoptosis (XIAP)-associated factor 1 (XAF1) was analyzed in 39 specimens by immunohistochemistry analysis.Results:We observed that silencing PGK1 sensitized triple-negative breast cancer (TNBC) cell lines to paclitaxel treatment as a result of increased drug-induced apoptosis. Furthermore, mechanistic investigations suggested that XAF1 was increased in PGK1-knockdown cells along with the expression of the apoptotic proteins including cleaved caspase-3 and Bax. Immunohistochemistry analysis showed that PGK1 was negatively related to XAF1. Moreover, we found that downregulation of XAF1 reduced paclitaxel-induced apoptosis in PGK1-silenced triple-negative cell lines.Conclusion:Our results identified PGK1 as a potential biomarker for the treatment of TNBC, and inhibition of PGK1 expression might represent a novel strategy to sensitize TNBC to paclitaxel treatment.

Background/Aims: Little is known about the potential mechanism of action for androgen receptor (AR) targeting treatment in estrogen receptor (ER)-negative breast cancer. This study aimed to evaluate AR status and its prognosis in four breast cancer subtypes. Bicalutamide has been identified as an AR antagonist and used for treating AR+/ER- breast cancer in a phase II trial. Our studies will clarify its mechanism in breast cancer treatment. Methods: A total of 510 consecutive cases of invasive ductal cancer (IDC) were evaluated in this study. The expression of AR was analyzed by immunohistochemistry and compared with patient survival, and its implications were evaluated in four subtypes of IDC. We examined bicalutamide as an AR antagonist to inhibit proliferation and increased apoptosis in AR+/ER- breast cancer cell lines. We explored the tumor suppressive functions of bicalutamide in vitro and vivo and its related mechanisms in AR+/ER- breast cancer. Results: AR expression was related to that of ER (P

// Yun Zhan 1, 4, * , Xukun Li 1, * , Xiaoshuan Liang 2 , Lin Li 1 , Bangrong Cao 1 , Baona Wang 3 , Jianlin Ma 1 , Fang Ding 1 , Xiang Wang 3 , Da Pang 2 , Zhihua Liu 1 1 State Key Laboratory of Molecular Oncology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China 2 Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, China 3 Department of Breast Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China 4 State Key Laboratory of Bioactive Substances and Function of Natural Medicine, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China * These authors have contributed equally to this work Correspondence to: Zhihua Liu, email: liuzh@cicams.ac.cn Keywords: miR-182, SNAI1, colonization, metastasis, breast cancer Received: June 15, 2016 Accepted: November 07, 2016 Published: November 24, 2016 ABSTRACT Metastasis is a multi-step process. Tumor cells occur epithelial-mesenchymal transition (EMT) to start metastasis, then, they need to undergo a reverse progression of EMT, mesenchymal-epithelial transition (MET), to colonize and form macrometastases at distant organs to complete the whole process of metastasis. Although microRNAs (miRNAs) functions in EMT process are well established, their influence on colonization and macrometastases formation remains unclear. Here, we established an EMT model in MCF-10A cells with SNAI1 overexpression, and characterized some EMT-related microRNAs. We identified that miR-182, which was directly suppressed by SNAI1, could enable an epithelial-like state in breast cancer cells in vitro , and enhance colonization and macrometastases in vivo . Subsequent studies showed that miR-182 exerted its function through targeting its suppressor SNAI1. Moreover, higher expression level of miR-182 was detected in metastatic lymph nodes, compared with paired primary tumor tissues. In addition, the expression level of miR-182 was negatively correlated with that of SNAI1 in these clinical specimens. Taking together, our findings describe the role of miR-182 in colonization and macrometastases in breast cancer for the first time, and provide a promise for diagnosis or therapy of breast cancer metastasis.

Standardized methods for the detection and assessment of circulating tumor DNA (ctDNA) in breast cancer are not sufficient. In the present study, the method and the potential application of ctDNA in the diagnosis of breast cancer were explored. DNA was extracted from the tumor tissues, plasma and peripheral blood cells of 11 patients with early-stage invasive breast cancer. Primers were designed against the exons of phosphatidylinositol-4,5-biphosphate 3-kinase catalytic subunit α, p53, epidermal growth factor receptor, Akt and phosphatase and tensin homolog. The amplicon-based method for whole-exon sequencing was performed. The associations between the ctDNA mutant frequency with the tumor DNA mutant frequency, and the ctDNA concentration with clinical data were analyzed. A linear association was identified between the concentration of ctDNA and the tumor volume for the 3 patients with basal-like breast cancer, and not in other subtypes. The mutation frequency differed the least between ctDNA and tissue DNA in basal-like breast cancer. ctDNA retained the constituent ratio of gene mutations identified in the corresponding tumor tissue. The ctDNA detection rate depended to a certain extent on the mutation frequency in tumor tissue; for example, a mutant locus with a mutation frequency of >30% in tissues presented a detection rate of >40% in plasma samples, whereas a locus with a mutation frequency of

In recent years, with the development of transcriptomics, the effect of long non-coding RNAs (LncRNAs) on the regulation of biological processes is being elucidated. LncRNAs play an important role in tumor occurrence and development. LncRNA associated with microvascular invasion in hepatocellular carcinoma (LncRNA MVIH) was first identified in hepatocellular carcinoma and is associated with angiogenesis, tumor growth and metastasis upregulation, and poor recurrence-free survival. MVIH has an important role in non-small cell lung cancer, in which it promotes cell proliferation and metastasis, and high MVIH expression indicates poor overall survival. However, the involvement of MVIH in breast cancer is unclear. Our research revealed that the expression levels of MVIH in breast cancer tissues were higher than in adjacent noncancerous tissues, and high MVIH expression was correlated with Ki67 expression. Moreover, breast cancer patients with high MVIH expression levels showed poor overall survival and disease-free survival. Multivariate analysis results indicated that MVIH was an independent prognostic factor in breast cancer. In addition, upregulated MVIH expression levels promoted cell proliferation and cell cycle, and inhibited cell apoptosis, while reduced MVIH expression showed the converse. In summary, our findings suggest that MVIH may have an important role in breast cancer and may serve as a new biomarker and a potential therapeutic target.

MicroRNAs (miRNAs) are single-stranded, small non-coding RNA molecules that participate in important biological processes. Although the functions of many miRNAs in breast cancer metastasis have been established, the role of others remains to be characterized. To identify additional miRNAs involved in metastasis, we performed a genetic screen by transducing a Lenti-miR™ virus library into MCF-7 cells. Using transwell invasion assays we identified human miR-548j as an invasion-inducing miRNA. The endogenous levels of miR-548j expression in breast cancer cell lines were shown to correlate with invasiveness. Moreover, miR-548j was shown to stimulate breast cancer cell invasion and metastasis in vitro and in vivo, but had no effect on proliferation. Next, using a series of in vitro and in vivo experiments, we found that Tensin1 served as a direct and functional target of miR-548j. Both miR-548j and Tensin1 modulated the activation of Cdc42 to regulate cell invasion and siCdc42 or the selective Cdc42 inhibitor ML141 suppressed the pathway of miR-548j-mediated cell invasion. Furthermore, a strong correlation between miR-548j, Tensin1, metastasis and survival was observed using two sets of clinical breast cancer samples. Our findings demonstrate that miR-548j functions as a metastasis-promoting miRNA to regulate breast cancer cell invasion and metastasis by targeting Tensin1 and activating Cdc42, suggesting a potential therapeutic application in breast cancer.

The aim of this study is to investigate the expression of ribosome-binding protein 1 (RRBP1) in invasive breast cancer and to analyze its relationship to clinical features and prognosis. RRBP1 expression was studied using real-time quantitative PCR and western blotting using pair-matched breast samples and immunohistochemical staining using a tissue microarray. Then the correlation between RRBP1 expression and clinicopathologic features was analyzed. RRBP1 mRNA and protein expression were significantly increased in breast cancer tissues compared with normal tissues. The protein level of RRBP1 is proved to be positively related to histological grade (P = 0.02), molecular subtype (P = 0.048) and status of Her-2 (P = 0.026) and P53 (P = 0.015). We performed a grade-stratified analysis of all patients according to the level of RRBP1 expression and found that RRBP1 overexpression highly affected overall survival in patients with early-stage (I and II) tumors (P = 0.042). Furthermore, Her-2 positive patients with negative RRBP1 expression had longer overall survival rates than those with positive RRBP1 expression (P = 0.031). Using multivariate analysis, it was determined that lymph node metastasis (LNM, P = 0.002) and RRBP1 expression (P = 0.005) were independent prognosis factors for overall survival. RRBP1 is a valuable prognostic factor in Her-2-positive breast cancer patients, indicating that RRBP1 is a potentially important target for the prediction of prognosis.

Low-dose metronomic (LDM) paclitaxel therapy displayed a stronger anti-angiogenic activity on breast tumors with fewer side effects. Upregulation of anti-angiogenic factor Thrombospondin-1 (TSP-1) accords for therapeutic potency of LDM paclitaxel, but its molecular mechanism has not been elucidated yet. microRNAs (miRNAs) have emerged as new important regulators of tumor growth and metastasis. Here, we hypothesize that miRNAs are involved in TSP-1 overexpression in paclitaxel LDM therapy of breast tumors. The miRNA profile of tumor tissues from control, LDM and MTD groups in 4T1 mouse breast cancer model was detected by microarray, and then verified by quantitative real-time PCR (qRT-PCR). Luciferase assay and western blot were employed to explore the mechanisms of miRNAs involved in this process. We found that let-7f, let-7a, miR-19b and miR-340-5p were reduced by >2 fold, and miR-543* and miR-684 were upregulated by at least 50% in paclitaxel LDM therapy. qRT-PCR verification revealed that let-7f level was reduced most significantly in LDM therapy. Computational prediction using TargetScan and miRanda suggested THBS1 which encodes TSP-1 as a potential target for let-7f. Luciferase activity assay further confirmed that let-7f may bind to 3'UTR of THBS1 gene and inhibit its activity. Moreover, forced expression of let-7f led to a decrease of TSP-1 at both mRNA and protein levels in MCF-7 cells. Contrastly, let-7f inhibition induced an increased expression of THBS1 mRNA and TSP-1 protein, but did not affect the proliferation and apoptosis of MCF-7 cells. Paclitaxel LDM therapy led to a decrease of let-7f and the elevation of TSP-1 protein expression in MCF-7 cells, while overexpression of let-7f may abolish LDM-induced the upregulation of TSP-1 in MCF-7 cells. In summary, let-7f inhibition contributed to the upregulation of TSP-1 in paclitaxel LDM therapy, independently of proliferation, cell cycle arrest and apoptosis of breast cancer. This study indicates let-7f as a potential therapeutic target for breast tumor.

Copy number variation (CNV) is crucial for gene regulation in humans. A number of studies have revealed that CNV contributes to the initiation and progression of cancer. In this study, we analysed four breast cancer cell lines and six fresh frozen tissues from patients to evaluate the CNV present in the genome using microarray-based comparative genomic hybridization (aCGH). Six genes located at 16q22.1 were analysed by real-time PCR. The real-time PCR analysis revealed that the loss of CDH1/E2F4 may be associated with worse clinical and pathological findings. Interestingly, covariation of CDH1, CDH3, CTCF and E2F4 was found to be associated with triple negative breast cancer and HER-2 receptor status. In conclusion, our study supports the idea that CNV at 16q22.1 in breast cancer is a frequent event; furthermore, it reveals the covariation of CDH1, CDH3, CTCF and E2F4. The role of the covariation is more complex than a simple additive effect of these four separate genes, which may provide a novel target for breast cancer.

Background and objectives Although there is growing evidence supporting the hypothesis that fibroblast growth factor receptor 2 (FGFR2) is one of the few candidate genes linked with breast cancer susceptibility, the precise role of FGFR2 protein expression in breast cancer is still unknown. Our study examines FGFR2 protein expression in breast cancer and determines its associations with clinicopathological features and survival. Methods Specimens from 125 invasive ductal carcinoma grade 2 (IDC2) breast cancer patients were investigated by immunohistochemistry for FGFR2 protein expression. Associations between the expression of FGFR2 and various clinicopathological features as well as survival status were studied. Result Cytoplasmic and nuclear FGFR2 were expressed in 64.8% and 56.8% of breast cancer patients, respectively. Cytoplasmic FGFR2 expression was significantly associated with tumor size and TNM stage. Furthermore, patients with high expression levels of cytoplasmic and nuclear FGFR2 showed much lower overall survival (OS) and disease-free survival (DFS) rates than those patients with low FGFR2 expression. Cytoplasmic FGFR2 expression and lymph node metastasis were independent prognostic factors for both DFS and OS by multivariate analysis. Conclusions High FGFR2 expression is correlated with poor OS and DFS in breast cancer patients. It could be a biomarker for poor prognosis. J. Surg. Oncol. 2012; 105:773–779. © 2011 Wiley Periodicals, Inc.

Background Metaplastic breast carcinoma is a rare aggressive malignant neoplasm. The purposes of this study are to review the pathologic features and clinical outcomes of metaplastic breast carcinoma compared to invasive ductal carcinoma and to evaluate the prognosis of metaplastic breast carcinoma. Methods The cases of 55 patients with metaplastic breast carcinomapresenting between 1991 and 2006 were analyzed and compared to the cases of 767 age-matched patients with invasive ductal carcinoma from the same time period. Results The group of patients with metaplastic breast carcinoma presented with a larger tumor size, lower lymph node involvement, higher percentage of triple-negative (estrogen receptor-, progesterone receptor- and human epidermal growth factor receptor-2-negative) cases, and Ki-67 over-expression compared with the group of patients with invasive ductal carcinoma and triple-negative invasive ductal carcinomas. Patients in the metaplastic breast carcinoma group tended to have more local (often chest wall) recurrences (P = 0.038) and distant (often lung) metastases (P = 0.001) than those in the invasive ductal carcinomas group. The prognosis of metaplastic breast carcinoma was poorer than that of invasive ductal carcinoma and triple-negative invasive ductal carcinomas; the 5-year overall survival rate was 54.5% in metaplastic breast carcinoma versus 85.1% in invasive ductal carcinoma, and 73.3% in triple-negative invasive ductal carcinomas (P P P = 0.010; P = 0.010; P = 0.035) and 5-year disease-free survival (P = 0.020; P = 0.018; P = 0.049). Conclusions Metaplastic breast carcinoma shows a poorer prognosis than both invasive ductal carcinoma and triple-negative invasive ductal carcinomas. Tumor size larger than 5.0 cm, lymph node involvement and Ki-67 ≥14% indicate a poor prognosis in patients with metaplastic breast carcinoma.

ARID1A (AT-rich interactive domain 1A) has recently been identified as a tumor suppressor gene. Its mRNA expression is significantly low in many breast cancers; this is often associated with more aggressive phenotypes. However, the underlying molecular mechanism for its low expression has not been fully understood. This study was undertaken to evaluate the contribution of gene copy number variation, mutations, promoter methylation and histone modification to ARID1A’s low expression. 38 pairs of breast invasive ductal carcinomas and their normal breast tissue counterparts from the same patients were randomly selected for gene expression and copy number variation detection. Promoter methylation and histone modification levels were evaluated by MeDIP-qPCR and ChIP-qPCR, respectively. PCR product Sanger sequencing was carried out to detect the exon mutation rate. Twenty-two out of 38 invasive ductal carcinomas in the study (57.9%) revealed ARID1A mRNA low expression by realtime RT-PCR. The relative promoter methylation level was, significantly higher in ARID1A mRNA low expression group compared with its high expression group (p