Immunohistochemical localization of metallothionein in endometrial lesions.
Metallothioneins (MTs) are a group of ubiquitous low-molecular-weight proteins essential for the protection of cells against heavy metal ion toxicity. The immunohistochemical expression of MT was studied by immunohistochemistry using a monoclonal antibody (E9) against a conserved epitope of I and II isoforms in a series of 89 endometrial carcinomas, 34 cases of hyperplasia, and 32 samples of normal endometrium. In secretory phase endometrium, extensive MT expression was detected in most cases (92.4%). In contrast, MT immunoreactivity was confined to small foci in 22.2% of proliferative phase cases. The MT values in normal endometrium were inversely correlated with oestrogen receptor (ER) content (p<0.0001), progesterone receptor (PgR) content and with PCNA (p<0.0001) and MIB1 (p=0.001) scores. In hyperplastic lesions, MT expression was detected only in 3.3% of cases, while in the group of carcinomas it was observed in 23.1%. A statistically significant difference of MT expression was observed between carcinomas and simple hyperplasias (p=0.03). In carcinomas, MT expression was positively correlated with grade (p=0.0065), MIB1 (p=0.022), and p53 (p=0.006) expression, and inversely with PgR (p=0.03). A trend of inverse correlation between MT and ER receptor was also detected (p=0.07). These data suggest that MT expression seems to be under hormonal control in normal endometrium; that it may modify p53 expression; and that it could be used as an additional biological marker indicating aggressive behaviour in endometrial lesions.
Ioachim
E E
EE
Department of Pathology, Medical School, University of Ioannina, Greece.
Kitsiou
E
E
Carassavoglou
C
C
Stefanaki
S
S
Agnantis
N J
NJ
D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism*; D004714:Endometrial Hyperplasia / Q000378:metabolism; D016889:Endometrial Neoplasms / Q000378:metabolism* / Q000473:pathology; D004717:Endometrium / Q000378:metabolism; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008668:Metallothionein / Q000378:metabolism*; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D011379:Prognosis
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D008668:Metallothionein