title: MicroRNA expression analysis in triple-negative (ER, PR and Her2/neu) breast cancer.
abstract: miRNAs are small, regulatory molecules approximately 21-24 nucleotides in length. They function at the post-transcriptional level by controlling the expression of more than 50% of human protein-coding genes and play an essential role in cell signaling pathways. The objective of the present study was to explore the expression profile of oncomiRs and tumor-suppressor miRs, and to define their possible correlations in triple-negative (ER, PR and Her2/neu) primary breast cancers. Forty-nine primary triple-negative breast cancer cases, along with 34 matched tumor-associated normal samples were investigated for the expression of 9 miRNAs using qPCR. Relationships between the expression of miR-10b, miR-21, miR-122a, miR-145, miR-205, miR-210, miR-221, miR-222 and miR-296 and the pathologic features of the tumors were examined, as were the influences of miR expression on patient overall and cancer-specific survival. miR-21, miR-210 and miR-221 were significantly overexpressed, whereas miR-10b, miR-145, miR-205, miR-122a were significantly underexpressed in the triple-negative primary breast cancers. Significant correlations among all of the studied miRs were scored both in the breast cancer and control tissue. Expression of miR-222 and miR-296 did not exhibit any significant difference between the breast cancer and normal tissue. There was a non-significant trend for high expression levels of the microRNAs, miR-21, miR-210, miR-221 and miR-222, to be associated with worse patient disease-free and overall survival. miR-21, miR-210 and miR-221 expression plays a significant role in triple- negative primary breast cancers.
authors.affiliation: Department of Surgical Pathology, Medical Faculty, University of Crete, Crete, Greece.
authors.forename: Jelena
authors.initials: J
authors.lastname: Radojicic
authors.forename: Apostolos
authors.initials: A
authors.lastname: Zaravinos
authors.forename: Thomas
authors.initials: T
authors.lastname: Vrekoussis
authors.forename: Maria
authors.initials: M
authors.lastname: Kafousi
authors.forename: Demetrios A
authors.initials: DA
authors.lastname: Spandidos
authors.forename: Efstathios N
authors.initials: EN
authors.lastname: Stathopoulos
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics* / Q000401:mortality; D005260:Female; D006801:Humans; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*; D011960:Receptors, Estrogen / Q000235:genetics*; D011980:Receptors, Progesterone / Q000235:genetics*; D015996:Survival Rate
chemical_list: D035683:MicroRNAs; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human