title: A method to monitor mRNA levels in human breast tumor cells obtained by fine-needle aspiration.
abstract: A method based on the reverse transcriptase-polymerase chain reaction (RT-PCR) was developed that allows the determination of relative mRNA expression levels in fine-needle aspirates from human tumors. The method was developed for the c-erbB-2 gene, using the porphobilinogen deaminase (PBGD) gene as an internal standard. It was validated for mRNA isolated from cell lines and for material obtained by fine-needle aspiration from human breast cancer. Gene expression levels were determined by measuring the activity of radiolabeled RT-PCR-amplified gene-specific bands with a phosphor imager. At least four points are measured on the log-linear part of the amplification cycle versus signal intensity curves, and subsequently the distance between the curves of the gene of interest and that of an internal standard gene is used to calculate the relative expression levels. The method worked equally well with the BRCA1 gene, illustrating that it can be generalized to other genes. The method is suitable to measure or monitor semiquantitively gene expression levels in accessible human tumors in situ.
authors.affiliation: Division of Experimental Therapy, The Netherlands Cancer Institute, Amsterdam.
authors.forename: M S
authors.initials: MS
authors.lastname: de Lange
authors.forename: B
authors.initials: B
authors.lastname: Top
authors.forename: C
authors.initials: C
authors.lastname: Lambrechts
authors.forename: R A
authors.initials: RA
authors.lastname: Maas
authors.forename: H L
authors.initials: HL
authors.lastname: Peterse
authors.forename: W J
authors.initials: WJ
authors.lastname: Mooi
authors.forename: L J
authors.initials: LJ
authors.lastname: van 't Veer
authors.forename: S
authors.initials: S
authors.lastname: Rodenhuis
mesh_terms: D019313:BRCA1 Protein / Q000235:genetics; D001707:Biopsy, Needle; D015152:Blotting, Northern; D001943:Breast Neoplasms / Q000737:chemistry* / Q000235:genetics*; D005240:Feasibility Studies; D005260:Female; D015870:Gene Expression; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis* / Q000096:biosynthesis; D012044:Regression Analysis; D015203:Reproducibility of Results; D014407:Tumor Cells, Cultured
chemical_list: D019313:BRCA1 Protein; D012333:RNA, Messenger