title: MicroRNA expression differentiates between primary lung tumors and metastases to the lung.
abstract: For surgical pathologists, distinguishing whether a pulmonary neoplasm is primary or metastatic can be challenging, and current biomarkers do not always aid lung tumor classification. The tissue-associated expression of microRNA likely explains the remarkable finding that many tumors can be classified based solely on their microRNA expression signature. Here we show that microRNAs can serve as biomarkers for lung tumor classification. Using microRNA microarray data generated from 76 formalin-fixed, paraffin-embedded (FFPE) samples of either primary lung cancer or metastatic tumors to the lung, we have identified a set of microRNAs expressed differentially between these two groups. This set includes hsa-miR-182, which was most strongly over-expressed in the lung primary tumors, and hsa-miR-126, which was over-expressed in the metastatic tumors. The differential expression of this set of microRNAs was confirmed using qRT-PCR on a set of 54 samples. In light of our data, microRNA expression should be considered as a potential clinical biomarker for surgical pathologists faced with discerning the tumor type of an inscrutable lung neoplasm.
authors.affiliation: Department of Pathology, Sheba Medical Center, Tel-Hashomer, 52621, Israel. barshack@sheba.health.gov.il
authors.forename: Iris
authors.initials: I
authors.lastname: Barshack
authors.forename: Gila
authors.initials: G
authors.lastname: Lithwick-Yanai
authors.forename: Arnon
authors.initials: A
authors.lastname: Afek
authors.forename: Kinneret
authors.initials: K
authors.lastname: Rosenblatt
authors.forename: Hila
authors.initials: H
authors.lastname: Tabibian-Keissar
authors.forename: Merav
authors.initials: M
authors.lastname: Zepeniuk
authors.forename: Lahav
authors.initials: L
authors.lastname: Cohen
authors.forename: Harel
authors.initials: H
authors.lastname: Dan
authors.forename: Orit
authors.initials: O
authors.lastname: Zion
authors.forename: Yulia
authors.initials: Y
authors.lastname: Strenov
authors.forename: Sylvie
authors.initials: S
authors.lastname: Polak-Charcon
authors.forename: Marina
authors.initials: M
authors.lastname: Perelman
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics*; D003937:Diagnosis, Differential; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology* / Q000556:secondary*; D035683:MicroRNAs; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D014408:Biomarkers, Tumor; D035683:MicroRNAs