title: Housekeeping genes in cancer: normalization of array data.
abstract: Biological maintenance of cells under variable conditions should affect gene expression of only certain genes while leaving the rest unchanged. The latter, termed "housekeeping genes," by definition must reflect no change in their expression levels during cell development, treatment, or disease state anomalies. However, deviations from this rule have been observed. Using DNA microarray technology, we report here variations in expression levels of certain housekeeping genes in prostate cancer and a colorectal cancer gene therapy model system. To highlight, differential expression was observed for ribosomal protein genes in the prostate cancer cells and beta-actin in treated colorectal cells. High-throughput differential gene expression analysis via microarray technology and quantitative PCR has become a common platform for classifying variations in similar types of cancers, response to chemotherapy, identifying disease markers, etc. Therefore, normalization of the system based on housekeeping genes, such as those reported here in cancer, must be approached with caution.
authors.affiliation: PerkinElmer Life Sciences, Boston, MA, USA.
authors.forename: Anis H
authors.initials: AH
authors.lastname: Khimani
authors.forename: Abner M
authors.initials: AM
authors.lastname: Mhashilkar
authors.forename: Alvydas
authors.initials: A
authors.lastname: Mikulskis
authors.forename: Michael
authors.initials: M
authors.lastname: O'Malley
authors.forename: Jennifer
authors.initials: J
authors.lastname: Liao
authors.forename: Eva E
authors.initials: EE
authors.lastname: Golenko
authors.forename: Pat
authors.initials: P
authors.lastname: Mayer
authors.forename: Sunil
authors.initials: S
authors.lastname: Chada
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Killian
authors.forename: Steven T
authors.initials: ST
authors.lastname: Lott
mesh_terms: D000465:Algorithms; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D002138:Calibration; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism*; D020869:Gene Expression Profiling / Q000379:methods* / Q000592:standards; D006801:Humans; D019169:Jurkat Cells; D008297:Male; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods* / Q000592:standards; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins