Comparing MicroRNA Profilings of Purified HER-2-Negative and HER-2-Positive Cells Validates miR-362-5p/Sema3A as Characteristic Molecular Change in Triple-Negative Breast Cancers

• Published in: Disease markers 2019, Vol.2019 (2019), p.1-12
• Main Authors: Wang, Jianfeng, Qin, Shengying, Zhang, Yanfei, Sun, Leiqin, He, Qi, Zhang, Xiaoqing, Fan, Junwei
• Format: Article
• Language: English
• Subjects: Analysis; Arrays; Biomarkers; Biomarkers, Tumor - genetics; Breast cancer; Breast carcinoma; Cancer therapies; Cell Line, Tumor; Chromosome 5; DNA microarrays; ErbB-2 protein; Ethanol; Female; Gene amplification; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Humans; Hybridization; Immunohistochemistry; Labeling; Laser Capture Microdissection; MicroRNA; MicroRNAs; MicroRNAs - genetics; miRNA; Multivariate analysis; Neoplasm Staging; Oligonucleotide Array Sequence Analysis; Prognosis; Proteins; Real time; Receptor, ErbB-2 - genetics; Ribonucleic acid; RNA; Semaphorin-3A - genetics; Semaphorin-3A - metabolism; Semaphorins; Software; Specimen preparation; Statistical analysis; Survival Analysis; Therapeutic applications; Tissues; Triple Negative Breast Neoplasms - genetics; Triple Negative Breast Neoplasms - metabolism; Triple Negative Breast Neoplasms - pathology; Tumor cells; Tumors
• ISSN: 0278-0240; 1875-8630
• DOI: 10.1155/2019/6057280

Background. HER-2 is a key molecule serving as the therapeutic target, prognostic biomarker, and classification marker in breast cancer. Accurate microRNA profilings had not been conducted in purified tumor cells of HER-2-negative and HER-2-positive tissue specimens obtained from breast cancer patients. Methods. (i) Differential expression microRNA discovery using laser capture microdissection- (LCM-) assisted specimen preparation and microRNA array chips on HER-2 overexpressing and triple-negative breast carcinoma (TNBC) subtype tissues, (ii) differential expression microRNA validation by quantitative real-time PCR, and (iii) independent validation on tissue microarray. Results. Five microRNAs (miR-20a-5p, miR-221-3p, miR-362-5p, miR-502-3p, and miR-222-3p) were screened and validated as upregulated microRNAs in TNBC cells comparing to HER-2 overexpressing cells using a microRNA array (5 cases in each group) and quantitative real-time PCR (20 cases in each group). The expression difference of miR-362-5p had the most significant statistical significance (p=0.0016) among the five microRNAs. The expression of miR-362-5p and its target gene Sema3A was further analyzed using in situ hybridization (ISH) and immunohistochemistry on standard tissue sections (n=150). 70.8% of HER-2-negative cells showed moderate expression of miR-362-5p whereas 20.4% HER-2-negative cells correlated with strong expression of miR-362-5p (p