title: Deep sequencing reveals small RNA characterization of invasive micropapillary carcinomas of the breast.
abstract: Invasive micropapillary carcinoma (IMPC) is an uncommon histological type of breast cancer. IMPC has a special growth pattern and a more aggressive behavior than invasive ductal carcinomas of no special types (IDC-NSTs). microRNAs are a large class of non-coding RNAs involved in the regulation of various biological processes. Here, we analyzed the small RNA transcriptomes of five formalin-fixed paraffin-embedded (FFPE) pure IMPC samples and five FFPE IDC-NSTs samples by means of next-generation sequencing, generating a total of >170,000,000 clean reads. In an unsupervised cluster analysis, differently expressed miRNAs generated a tree with clear distinction between IMPC and IDC-NSTs classes. Paired fresh-frozen and FFPE specimens showed very similar miRNA expression profiles. By means of RT-qPCR, we further investigated miRNA expression in more IMPC (n = 22) and IDC-NSTs (n = 24) FFPE samples and found let-7b, miR-30c, miR-148a, miR-181a, miR-181a*, and miR-181b were significantly differently expressed between the two groups. We also elucidated several features of miRNA in these breast cancer tissues including 5' variability, miRNA editing, and 3' untemplated addition. Our findings will lead to further understanding of the invasive potency of IMPC and gain an insight into the diversity and complexity of small RNA molecules in breast cancer tissues.
authors.affiliation: Department of Breast Cancer Pathology and Research Laboratory, Tianjin Medical University Cancer Institute and Hospital, Tianjin, People's Republic of China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Li
authors.forename: Cuicui
authors.initials: C
authors.lastname: Yang
authors.forename: Lili
authors.initials: L
authors.lastname: Zhai
authors.forename: Wenwei
authors.initials: W
authors.lastname: Zhang
authors.forename: Jing
authors.initials: J
authors.lastname: Yu
authors.forename: Feng
authors.initials: F
authors.lastname: Gu
authors.forename: Ronggang
authors.initials: R
authors.lastname: Lang
authors.forename: Yu
authors.initials: Y
authors.lastname: Fan
authors.forename: Meihua
authors.initials: M
authors.lastname: Gong
authors.forename: Xiuqing
authors.initials: X
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Fu
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002291:Carcinoma, Papillary / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D008207:Lymphatic Metastasis; D035683:MicroRNAs / Q000235:genetics / Q000302:isolation & purification; D009361:Neoplasm Invasiveness / Q000235:genetics
chemical_list: D035683:MicroRNAs