Cyclooxygenase-2 expression and relationship to tumour progression in human renal cell carcinoma.
OBJECTIVE
Cyclooxygenase (COX), which catalyses the synthesis of prostaglandins from arachidonic acid, has two isoforms; COX-1 and COX-2. There is ample evidence to suggest an important role for COX-2 in cancer. The aim of this study was to evaluate the clinical significance of COX-2 expression and its localization in the development and progression of human renal cell carcinoma (RCC).


RESULTS
The expression and localization of COX-2 were evaluated in human RCC tissues from 75 patients by immunohistochemistry. Immunoreactive COX-2 protein was observed in all cases of RCC, and the levels of COX-2 expression were correlated with tumour grade and pathological stage. Expression of COX-2 was higher in the granular cell subtype than in the clear cell subtype of RCC. Immunoelectron microscopy revealed that COX-2 was expressed in the nuclear membrane, rough endoplasmic reticulum, Golgi complex and mitochondrial membrane of RCC cells.


CONCLUSIONS
COX-2 overexpression within these intracellular organelles in RCC may be associated with renal cell carcinogenesis and COX-2 may be a useful biomarker in RCC.
Hashimoto
Y
Y
Department of Urology, Central Institute for Electron Microscopic Research, Kitasato University, Tokyo, Japan.
Kondo
Y
Y
Kimura
G
G
Matsuzawa
I
I
Sato
S
S
Ishizaki
M
M
Imura
N
N
Akimoto
M
M
Hara
S
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor; D002292:Carcinoma, Renal Cell / Q000201:enzymology* / Q000473:pathology* / Q000648:ultrastructure; D051546:Cyclooxygenase 2; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000096:biosynthesis* / Q000235:genetics; D007680:Kidney Neoplasms / Q000201:enzymology* / Q000473:pathology* / Q000648:ultrastructure; D008297:Male; D008565:Membrane Proteins; D016253:Microscopy, Immunoelectron; D008875:Middle Aged; D009367:Neoplasm Staging; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis* / Q000235:genetics; D015854:Up-Regulation
D014408:Biomarkers, Tumor; D007527:Isoenzymes; D008565:Membrane Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases