Aromatase expression in normal human oral keratinocytes and oral squamous cell carcinoma.
Aromatase is the enzyme that catalyzes the conversion of androgen to oestrogen. Aromatase expression in extra-gonadal sites and local oestrogen synthesis play an important role in the physiological conditions and in the growth of certain neoplasms.


OBJECTIVE
The purpose of this study was to investigate aromatase expression in oral keratinocytes and oral squamous cell carcinoma (SCC).


METHODS
Immunocytochemistry and RT-nested PCR were used to detect aromatase protein and mRNA expression in primary human oral epithelial cell culture and in an oral SCC cell line. Immunohistochemistry was used to detect aromatase protein expression in frozen and archival human tissue sections of normal oral epithelium and oral SCC.


RESULTS
Cytoplasmic immunostaining was found in normal oral keratinocytes and SCC cells in culture. The common coding region of aromatase mRNA was detected in the oral keratinocytes derived from five different normal individuals and in the SCC cell line. However, there were variations in aromatase exon 1 expression among normal oral keratinocyte samples. Cytoplasmic staining was found in normal oral epithelium and well-differentiated oral SCC but not in poorly differentiated oral SCC by immunohistochemistry.


CONCLUSIONS
Aromatase was expressed in normal oral keratinocytes and oral SCC both in cell culture and in tissues, indicating local oestrogen synthesis in normal and neoplastic conditions of oral epithelium.
Cheng
Yi-Shing Lisa
YS
Diagnostic Sciences, Baylor College of Dentistry-Texas A and M University Health Science Center, 3302 Gaston Ave., Dallas, TX 75246, USA. ycheng@bcd.tamhsc.edu
Mues
Gabriele
G
Wood
David
D
Ding
Jiahuan
J
D000368:Aged; D000818:Animals; D001141:Aromatase / Q000032:analysis*; D002294:Carcinoma, Squamous Cell / Q000201:enzymology*; D002417:Cattle; D006801:Humans; D015603:Keratinocytes / Q000201:enzymology*; D008297:Male; D009061:Mouth Mucosa / Q000201:enzymology*; D009062:Mouth Neoplasms / Q000201:enzymology*; D009363:Neoplasm Proteins / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods
D009363:Neoplasm Proteins; D001141:Aromatase