A Novel lncRNA HOXC-AS3 Acts as a miR-3922-5p Sponge to Promote Breast Cancer Metastasis.

Purpose: The function of long noncoding RNAs (lncRNA) in breast cancer metastasis remains largely unknown. In this work, the role of HOXC-AS3 in breast cancer progression was investigated.Methods: By using Cancer Genome Atlas (TCGA) Database, we investigated the expression of HOXC-AS3 in breast cancer and explored the association between HOXC-AS3 expression and prognosis. Then, we studied the biological function of HOXC-AS3 in cell migration and invasion both in vitro and in vivo. Furthermore, the target miRNA of HOXC-AS3, and the target mRNA of miR-3922-5p were proved.Results: HOXC-AS3 is aberrantly overexpressed in breast cancers especially the HER2+ type. Moreover, high expression of HOXC-AS3 has a relationship with poor clinical outcomes of breast cancer. In addition, HOXC-AS3 regulates cell Invasion and migration both in vitro and in vivo. Our results demonstrated that miR-3922-5p was a direct target of HOXC-AS3, and PPP1R1A was a target of miR-3922-5p in breast cancer.Conclusions: The novel lncRNA HOXC-AS3 acts as a miR-3922-5p sponge to upregulate PPP1R1A protein expression, and thus results in promoting breast cancer metastasis. HOXC-AS3 could be a novel therapeutic target for breast cancer therapeutics.

Long non-coding RNA BRAF-regulated lncRNA 1 promotes lymph node invasion, metastasis and proliferation, and predicts poor prognosis in breast cancer.

Long non-coding RNAs (lncRNAs) are primary regulators of cancer development via their involvement in almost every aspect of cell biology. Recent studies have indicated that lncRNAs serve pivotal roles in breast cancer (BC) progression; however, to the best of our knowledge, the role of the lncRNA BRAF-regulated lncRNA 1 (BANCR) in BC has not yet been elucidated. The present study revealed that BANCR was overexpressed in BC cell lines and tissues, and could promote the clinical progression of disease, including increases in tumor size, lymph node metastasis and Tumor-Node-Metastasis stage. Furthermore, high BANCR expression was demonstrated to be associated with poor overall survival rates and early recurrence of BC in patients. Additionally, univariate and multivariate COX regression analyses identified high BANCR expression as an independent risk factor of poor prognosis of patients with BC. In addition, to verify the function of BANCR in BC cell lines, BANCR expression was silenced using short hairpin RNAs in MDA-MB-231 cells and overexpressed in MDA-MB-468 cells. An MTT assay and colony formation assay indicated that BANCR knockdown could suppress the proliferation of BC cells, whereas BANCR upregulation induced the proliferation of BC cells. Furthermore, BANCR silencing also reduced the migration and invasion of BC cells, as demonstrated via transwell migration and invasion assays. Consistently, the migration and invasion of BC cells increased upon BANCR ectopic overexpression in MDA-MB-468 cells. Mechanistically, matrix metallopeptidase 2/9 and epithelial-mesenchymal transition markers may be the potential targets of BANCR in regulating BC metastasis. In conclusion, BANCR overexpression could promote the clinical progression, metastasis and proliferation of BC and indicate poor prognosis of patients with BC. BANCR may therefore be a potential prognostic marker and therapeutic target of patients with BC.

Low expression of tyrosine-protein phosphatase nonreceptor type 12 is associated with lymph node metastasis and poor prognosis in operable triple-negative breast cancer.

BACKGROUND: Low tyrosine-protein phosphatase nonreceptor type 12 (PTPN12) expression may be associated with breast cancer growth, proliferation, and metastasis. However, the prognostic value of PTPN12 in breast cancer has not been clearly identified. PATIENTS AND METHODS: 51 triple-negative breast cancer (TNBC) patients and 83 non-TNBC patients with a histopathology diagnosis from October 2001 to September 2006 were included in this study. Immunohistochemical staining for PTPN12 on tissue microarrays was conducted. RESULTS: High PTPN12 expression was seen in 39.2% of TNBC and 60.2 % of non-TNBC cases. Low PTPN12 expression was associated with lymph node status (p = 0.002) and distant metastatic relapse (p = 0.002) in TNBC patients. Similarly, low PTPN12 expression in non-TNBC patients was significantly correlated with lymph node status (p = 0.002), stage (p = 0.002) and distant metastatic relapse (p = 0.039). The high PTPN12 expression group was associated with longer DFS and OS compared with low PTPN12 expression group only in TNBC cases (p = 0.005, p = 0.015), according to univariate Cox regression analysis. CONCLUSION: These findings provide evidence that low expression of PTPN12 is associated with worse prognosis and may be used as a potential prognostic biomarker in TNBC patients.

Clinical characteristics and survival analysis of breast cancer molecular subtypes with hepatic metastases.

BACKGROUND: The liver is one of the most common metastatic sites of breast cancer, hepatic metastases developing in 6%-25% of patients with breast cancer and being associated with a poor prognosis. The aim of this study was to analyze the survival and clinical characteristics of patients with hepatic metastases from breast cancer of different molecular subtypes and to investigate the prognostic and predictive factors that effect clinical outcome. METHODS: We retrospectively studied the charts of 104 patients with breast cancer hepatic metastases diagnosed at Sun Yat-sen University Cancer Center from December 1990 to June 2009. Subtypes were defined as luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) enriched, triple-negative (TN). Prognostic factor correlations with clinical features and treatment approaches were assessed at the diagnosis of hepatic metastases. RESULTS: The median survival time was 16.0 months, and the one-, two- three-, four-, five- year survival rates were 63.5%, 31.7%, 15.6%, 10.8%, and 5.4%, respectively. Median survival periods after hepatic metastases were 19.3 months (luminal A), 13.3 months (luminal B), 18.9 months (HER2-enriched), and 16.1 months (TN, P=0.11). In multivariate analysis, a 2 year-interval from initial diagnosis to hepatic metastasis, treatment with endocrine therapy, and surgery were independent prognostic factors. Endocrine therapy could improve the survival of luminal subtypes (P=0.004) and was a favorable prognostic factor (median survival 23.4 months vs. 13.8 months, respectively, P=0.011). Luminal A group of patients treated with endocrine therapy did significantly better than the Luminal A group of patients treated without endocrine therapy (median survival of 48.9 vs. 13.8 months, P=0.003). CONCLUSIONS: Breast cancer subtypes were not associated with survival after hepatic metastases. Endocrine therapy was a significantly favorable treatment for patients with luminal subtype.

A case report of primary small cell carcinoma of the breast and review of the literature.

Primary small cell carcinoma (SCC) of the breast, an exceedingly rare and aggressive tumor, is often characterized by rapid progression and poor prognosis. We report a case of primary SCC of the breast that was diagnosed through pathologic and immunohistochemical examinations. Computed tomography (CT) scans failed to reveal a non-mammary primary site. Due to the scant number of relevant case summaries, this type of tumor is proved to be a diagnostic and therapeutic challenge. Therefore, we also reviewed relevant literature to share expertise in diagnosis, clinicopathologic characteristics, treatment, and prognosis of this type of tumor. Future studies with more cases are required to define more appropriate treatment indications for this disease.