Matrix metalloproteinases and their inhibitors in human pituitary tumors.
OBJECTIVE
To determine the expression of matrix metalloproteinases (MMP)-1, -2, and -3 and the tissue inhibitors of metalloproteinases (TIMP)-1, -2, and -3 in 12 tissue samples from normal pituitary glands and in 28 human pituitary tumors ranging from Grade 0 to Grade IV, and to establish a correlation between the level of expression of MMPs and TIMPs and the tumor grade.


METHODS
The expression of MMPs and TIMPs was determined by Western blotting. MMP activity was detected by gelatin zymography.


RESULTS
MMPs were expressed in the majority of tumors, and their levels of expression were unrelated to tumor grade or to their invasive phenotype. Some correlation was observed between MMP activity detected by zymography and tumor grade. TIMP-2 and TIMP-3 were poorly expressed in high-grade tumors and strongly expressed in normal pituitary glands and in the majority of low-grade tumors.


CONCLUSIONS
No correlation could be established between the invasive potential of tumors and MMP-1, -2, and -3 expression levels. Some correlation was observed between MMP activity detected by zymography and tumor grade. A good inverse correlation was observed between TIMP-2 and TIMP-3 expression levels and tumor grade. These data suggest that monitoring the expression of TIMP-2 and TIMP-3 or gelatinolytic activity could be of prognostic value.
Beaulieu
E
E
Laboratoire de Médecine Moléculaire, Centre de Cancérologie Charles-Bruneau, Hôpital Ste-Justine-Université du Québec à Montréal, Canada.
Kachra
Z
Z
Mousseau
N
N
Delbecchi
L
L
Hardy
J
J
Béliveau
R
R
D000236:Adenoma / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D015153:Blotting, Western; D005260:Female; D006801:Humans; D008297:Male; D020782:Matrix Metalloproteinases / Q000032:analysis*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009384:Paraneoplastic Endocrine Syndromes / Q000473:pathology; D010902:Pituitary Gland / Q000473:pathology; D010911:Pituitary Neoplasms / Q000473:pathology*; D011379:Prognosis; D012016:Reference Values; D019714:Tissue Inhibitor of Metalloproteinases / Q000032:analysis*
D019714:Tissue Inhibitor of Metalloproteinases; D020782:Matrix Metalloproteinases