The impact of gene expression microarrays in the evaluation of lung carcinoma subtypes and DNA copy number.
BACKGROUND
The development of targeted therapies creates a need to accurately classify tumors. Among the more pressing needs are the identification of the complete catalog of genes that are altered in cancer and the accurate discrimination of tumors based on their genetic background.


OBJECTIVE
To discuss the use of gene expression profiles to recapitulate the pathology and to distinguish the genetic background of non-small cell lung cancer. Also, to comment on using global analysis of gene expression to identify chromosomal regions carrying clusters of highly expressed genes, likely due to gene amplification. Gene amplification at these regions may target the activation of an oncogene critical to tumor development and potentially important in therapy.


METHODS
Review of relevant, recent literature on molecular alterations and expression analysis in lung cancer.


CONCLUSIONS
The complexity of genetic and epigenetic alterations and the cell type of origin confer marked patterns of gene expression to lung tumors, which differentiate different tumor entities.
Lung Cancer Group, Molecular Pathology Program, Spanish National Cancer Centre CNIO, Calle Melchor Fernandez Almagro 3, 28029 Madrid, Spain. msanchez@cnio.es
Montserrat
M
Sanchez-Cespedes
D002454:Cell Differentiation / Q000235:genetics; D044127:Epigenesis, Genetic / Q000235:genetics; D018628:Gene Dosage / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis