Comparison of c-myc expression in normal human bronchial epithelial cells and lung cancer cell lines using a quantitative fluorescence-based reverse transcriptase polymerase chain reaction method

Citation
Wr. Fields et al., Comparison of c-myc expression in normal human bronchial epithelial cells and lung cancer cell lines using a quantitative fluorescence-based reverse transcriptase polymerase chain reaction method, TOX METHOD, 9(3), 1999, pp. 173-188
Citations number
54
Categorie Soggetti
Pharmacology & Toxicology
Journal title
TOXICOLOGY METHODS
ISSN journal
10517235 → ACNP
Volume
9
Issue
3
Year of publication
1999
Pages
173 - 188
Database
ISI
SICI code
1051-7235(199907/09)9:3<173:COCEIN>2.0.ZU;2-#
Abstract
Mutations, either heritable or induced, can modulate the expression of onco genes and/or tumor suppressor genes and thereby alter the biology of the af fected cells. Overexpression of the c-myc oncogene appears to contribute to the development of small cell lung cancer, and has been used as an indicat or of poor prognosis for this tumor type. However neither the variability o f c-myc expression in noncancerous human lung tissue retrieved from differe nt donors nor the level of c-myc expression in various lung tu:mor types ha s been adequately studied. The authors have quantified and compared the exp ression of c-myc in normal human bronchial epithelial (NHBE) cells from sev eral noncancerous lungs and in transformed human lung cell lines. c-myc mRN A levels were determined through the annealing of a gene-specific probe to a target cDNA copy of the mRNA. The fluorescence signal liberated by the 5' -3' exonuclease-induced release of the re,porter dye from the annealed prob e during the extension cycle of polymerase chain reaction (PCR) was quantif ied spectrophotometrically. While NHBE cells from four donors expressed com parable levels of c-myc mRNA, the c-myc mRNA levels in large cell lung carc inoma (LCLC) and small cell lung carcinoma (SCLC) cell lines were 2.4- and 5.0-fold greater than in NHBE cells, respectively. In contrast, the lung ad enocarcinoma and adenosquamous carcinoma cell lines examined did not exhibi t an increase in c-myc expression relative to the NHBE cells. In summary, t his reverse/transcriptase polymerase chain reaction method readily quantifi es and distinguishes the level of c-myc mRNA in NHBE and human lung cancer cells. This technology may serve to characterize oncogene-related changes d uring tumorigenesis, to identify genetically predisposed individuals, and t o allow for earlier diagnosis and treatment of lung cancer.