p27(kip1) immunoreactivity correlates with long-term survival in pleural malignant mesothelioma.
BACKGROUND
Pleural malignant mesothelioma (PMM) is a rare and highly aggressive tumor, whose development is strictly related to occupational exposure to asbestos. The prognosis of PMM is generally poor (median survival, 4-12 months), but a few have a relatively long survival. The objective of this study was to evaluate the use of the cell cycle-related proteins p27(kip1) and MIB-1 as prognostic indicators of survival in PMMs.


METHODS
Of 621 PMMs, the authors selected 27 cases with a relatively long-term survival (> 24 months) and a control group of 36 PMMs having a shorter (usual) survival (< 24 months).


RESULTS
The expression of the p27(kip1) was significantly higher in the long-term survival group compared with the control (short survival) group (81.41% vs. 31.94%; P < 0.0001). The PMMs of epithelioid histotype had a significantly higher p27(kip1) immunoreactivity compared with those of biphasic type (59.24% vs. 38.94%; P = 0.02). In agreement with the data in the literature, the proliferative activity (as detected by MIB-1 immunoreactivity) was significantly higher in short than long survival PMMs (43.53% vs. 14.11%; P < 0.0001) and in the biphasic histotype than in the epithelioid type (43.19% vs. 26.02%; P = 0.006).


CONCLUSIONS
The combined expression of high/low p27(kip1) and low/high Ki-67 values identified with 100% specificity and sensitivity long versus short survivors. p27(kip1) represents a reliable additional predictive factor for PMMs and a useful marker to identify patients having a more favorable prognosis.
Bongiovanni
M
M
Department of Oncology, University of Turin, Turin, Italy.
Cassoni
P
P
De Giuli
P
P
Viberti
L
L
Cappia
S
S
Ivaldi
C
C
Chiusa
L
L
Bussolati
G
G
D000328:Adult; D000368:Aged; D034961:Antigens, Nuclear; D018797:Cell Cycle Proteins / Q000378:metabolism*; D050760:Cyclin-Dependent Kinase Inhibitor p27; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008654:Mesothelioma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D008875:Middle Aged; D009687:Nuclear Proteins / Q000378:metabolism; D010997:Pleural Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D016019:Survival Analysis; D025521:Tumor Suppressor Proteins
D034961:Antigens, Nuclear; D018797:Cell Cycle Proteins; D019394:Ki-67 Antigen; D009687:Nuclear Proteins; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27