Correlative expression of cyclooxygenase-1 (Cox-1) and human epidermal growth factor receptor type-2 (Her-2) in endometrial cancer.
OBJECTIVE
Cyclooxygenase-2 (Cox-2) is known to be associated with tumorigenesis in many cancers including endometrial cancer, while there is substantial evidence for the tumorigenicity of cyclooxygenase-1 (Cox-1). However, little is known about the involvement of Cox-1 in the development of endometrial cancer. The aim of this study was to determine whether cyclooxygenase-1 or -2 (Cox-1, Cox-2) is tumorigenetic, as well as whether these two cyclooxygenase isoforms correlate with the clinicopathological characteristics or with another two biomarkers, human epidermal growth factor receptor type-2 (Her-2) and vascular endothelial growth factor (VEGF), of endometrial cancer.


METHODS
At first, Cox-1 and Cox-2 levels in eight endometrial cancer cell lines were determined by means of real-time PCR. At second, the levels of four biomarkers (Cox-1, Cox-2, Her-2, and VEGF) in 70 endometrial cancer samples were determined by means of real-time PCR. Pairs of these biomarkers were subjected to correlation as each biomarker and clinical status or survival.


RESULTS
In the eight cell lines, the expression of Cox-1 and Cox-2 showed major variations in their mRNA levels. Analysis of the patient samples showed that the mRNA expression of Cox-1 was elevated significantly in the G1 (P=0.021) and G2 (P=0.036) groups, as was the mRNA expression of Her-2 in the two groups (P=0.036 and P=0.0029, respectively). The mRNA expression of Cox-1 and Her-2 were correlated (CI=0.671). None of the three biomarkers, Cox-1, Cox-2, and Her-2, was correlated with clinical status such as FIGO classification, myometrial invasion, or clinical outcome.


CONCLUSIONS
Cox-1, together with Her-2, may be involved in the early stage of endometrial cancer development.
Sugimoto
Takeshi
T
Clinical Research Division, Hyogo Medical Center for Adults, Akashi, Japan. tks_sugimoto@yahoo.co.jp
Koizumi
Tamio
T
Sudo
Tamotsu
T
Yamaguchi
Satoshi
S
Kojima
Atsumi
A
Kumagai
Shunichi
S
Nishimura
Ryuichirou
R
D000230:Adenocarcinoma / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology; D000328:Adult; D000368:Aged; D045744:Cell Line, Tumor; D051545:Cyclooxygenase 1 / Q000096:biosynthesis / Q000235:genetics*; D051546:Cyclooxygenase 2 / Q000096:biosynthesis / Q000235:genetics; D016889:Endometrial Neoplasms / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis / Q000235:genetics*
D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D007527:Isoenzymes; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; C496540:PTGS2 protein, human; C508053:ERBB2 protein, human