title: Complexity in regulation of microRNA machinery components in invasive breast carcinoma.
abstract: Altered expression of microRNA (miRNA) machinery components may play an important role in breast cancer progression. The objective of the current study was to evaluate Drosha, the DiGeorge syndrome critical region gene 8 (DGCR8), Dicer, and Argonaute 2 (AGO2) mRNA expression in invasive breast carcinoma (IBC) and to assess the value of clinical parameters on their expression. By using quantitative real-time PCR, we examined the expression of the four miRNA machinery components in 52 breast tumor tissues which are diagnosed as invasive ductal carcinoma and adjacent non-neoplastic tissues. In the present study, decreased mRNA expression levels of major miRNA machinery components were observed in IBC. The altered mRNA expression levels of DGCR8 and AGO2 are positively correlated with to each other. This study revealed for the first time that expression alterations of DGCR8 are significantly associated with estrogen receptor and Ki-67 status in IBC. Moreover, AGO2 mRNA expression level was significantly correlated with N stage. These results provided evidences that down-regulated the four miRNA machinery components may play an important role in breast pathobiology and that DGCR8 and AGO2 might be associated with important clinical factors.
authors.affiliation: Department of Pathology, School of Medicine, Keimyung University, 1095 Dalgubeoldaero, Dalseo-Gu, Daegu, 704-701, South Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Kwon
authors.forename: Jae-ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Bora
authors.initials: B
authors.lastname: Kim
authors.forename: Jong-Wook
authors.initials: JW
authors.lastname: Park
authors.forename: Taeg Kyu
authors.initials: TK
authors.lastname: Kwon
authors.forename: Sun Hee
authors.initials: SH
authors.lastname: Kang
authors.forename: Shin
authors.initials: S
authors.lastname: Kim
mesh_terms: D060565:Argonaute Proteins / Q000235:genetics* / Q000378:metabolism; D001940:Breast / Q000378:metabolism; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D053487:DEAD-box RNA Helicases / Q000235:genetics* / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007124:Immunoenzyme Techniques; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011379:Prognosis; D011506:Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D016601:RNA-Binding Proteins; D060888:Real-Time Polymerase Chain Reaction; D043244:Ribonuclease III / Q000235:genetics* / Q000378:metabolism
chemical_list: C466422:AGO2 protein, human; D060565:Argonaute Proteins; C474043:DGCR8 protein, human; D035683:MicroRNAs; D011506:Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C408087:DICER1 protein, human; C517918:DROSHA protein, human; D043244:Ribonuclease III; D053487:DEAD-box RNA Helicases