Kivonat:
Expression of heat shock proteins (HSPs) is of prognostic
significance in several tumor types. HSP expression levels were
determined in medulloblastomas and tested whether HSPs
expression was associated with prognostic parameters. Expression
of antiapoptotic HSP 27, HSP 70, and HSP 90 was investigated by
immunohistochemistry, on paraffin-embedded sections from 65
patients. Expression of HSPs was validated on internal vascular
controls and by Western blotting analysis. Sample evaluation was
based on the estimated percentage of HSP positive tumor cells.
For survival analysis Kaplan-Meier method, for statistical
analysis chi2 test, univariate analysis, and log rank test were
applied. Expression of HSPs varied in medulloblastomas. On the
basis of the average expression rate of HSPs, at HSP 27 and HSP
90 with a 10% cut off, and at HSP 70 with a 70% cut off 2 groups
were created. The amount of expression of any of the HSP types
was not significantly associated with known prognostic factors
(age of patient, extent of resection, presence of metastasis)
and histologic subtype. After an average follow-up period of
4.30 years, no significant difference was observed in survival
depending on the expression of HSP 27 or HSP 70 or HSP 90. The
high expression of HSPs indicates that these proteins are
potential therapeutic targets.