Gene expression analysis by cDNA microarray in oral cancers from two Western populations.
BACKGROUND
In this work, gene expression profile was examined in 19 cases of oral cancer (OC) obtained from patients from Sweden (n=8) and UK (n=11) and the findings were tested for correlation to patient's clinicopathological data.


METHODS
Following total RNA extraction, cDNA synthesis, labeling with fluorescent dyes and hybridization to the 21 k human oligonucleotide microarrays, slides were scanned and images were subjected to Genepix and J-Express analysis. Results for selected genes were validated by quantitative reverse transcriptase polymerase chain reaction (Q-RT-PCR).


RESULTS
42 genes were identified as being differentially expressed. These included 39 genes of known functions (such as fatty acid synthase (FASN), 5' nucleotidase, ecto (NT5E), high mobility group AT-hook (HMGA1), and v-fos FBJ murine osteosarcoma viral oncogene homolog (FOS)) and 3 novel genes; 26 (67%) of the 39 genes with known functions were previously reported in oral/head and neck tumors examined from other populations. Hierarchical clustering of the samples using the 42 genes demonstrated that samples mainly clustered in the same population.


CONCLUSIONS
These results illustrate that microarrays can be used to identify distinct patterns of gene expression in different populations, but with no direct association to clinicopathological parameters. The fact that 67% of the 39 genes with known functions found in this work were previously reported in oral/head and neck tumors from other populations provides clear evidence that development of these tumors follows the same biological pathways irrespective of the source of the samples used.
Department of Biomedicine, Jonas Lies vei 91, 5009 Bergen, Norway. mai.suhr@biomed.uib.no
Mai Lill Suhr
ML
Lunde
Saman
S
Warnakulasuriya
Lars
L
Sand
Jan M
JM
Hirsch
Endre N
EN
Vasstrand
Salah O
SO
Ibrahim
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology; D018076:DNA, Complementary / Q000235:genetics; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000235:genetics* / Q000473:pathology; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013548:Sweden
D018076:DNA, Complementary