Hsp27 (HSPB1): a possible surrogate molecular marker for loss of heterozigocity (LOH) of chromosome 1p in oligodendrogliomas but not in astrocitomas

CASTRO GN; CAYADO-GUTIERREZ N; MONCALERO V; LIMA P; LUCERO DE ANGELIS R; CHAVEZ V; CUELLO-CARRIÓN FD; CIOCCA DR

CELL STRESS & CHAPERONES.

SPRINGER

Lugar: Berlin; Año: 2012 vol. 17 p. 779 - 787

1355-8145

In oligodendrogliomas, 1p LOH is a predictor of good prognosis and treatment response. Incontrast, in uveal melanomas LOH of chromosome 3 has been linked to poor prognosis anddown-regulation of Hsp27. In the present study we have analyzed the expression of heatshock proteins (Hsps) to characterize subtypes of gliomas and their histopathologic features,and to correlate with other molecular markers including LOH of 1p. Biopsies from patientswith primary gliomas (n=65) were analyzed by immunohistochemistry, CISH and FISH andmethylation specific PCR (MSP). Elevated Hsp27 and Hsp70t expression levels wereassociated with high grade astrocytomas (p=0.0001 and p=0.01 respectively). In grade IIIoligodendrogliomas the Hsp27 levels were significantly higher (p=0.03). Low MGMTexpression was associated with grade II astrocytomas. Elevated beta-catenin expression wasassociated with grade III/IV astrocytomas (p=0.003), p53 (+) tumors were more frequentlyfound in grade III/IV astrocytomas (p=0,001). LOH on 1p was associated witholigodendroglial tumours. In addition, a higher Hsp27 expression correlated with LOH of 1p(p=0.017), this was also tested in two glioma cell lines. MSP was successful in only 6samples. No significant correlations were found for the other markers. In conclusion, inoligodendroglial tumors Hsp27 appeared as a surrogate marker of LOH of 1p which couldalso help to predict the disease prognosis. In gliomas, p53, Hsp27, Hsp70, MGMT and beta-catenin correlated with histopathological characteristics suggesting that these markers couldpredict the disease outcome and the response to treatments.