IMBECU   20882
INSTITUTO DE MEDICINA Y BIOLOGIA EXPERIMENTAL DE CUYO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Heat shock proteins Hsp27 and Hsp70 in gliomas: Correlation with 1p36 status, MGMT and other molecular markers
Autor/es:
GN CASTRO; N CAYADO-GUTIÉRREZ; FD CUELLO-CARRIÓN; P LIMA; R LUCERO DE ANGELIS; V CHÁVEZ; DR CIOCCA
Lugar:
Wood Hole, MA
Reunión:
Congreso; Heat Shock Proteins in Cancer and Immunology; 2010
Institución organizadora:
Harvard Medical School
Resumen:
Malignant gliomas comprise a wide range of neoplasms arismq from astrocytes (astrocytomas) and from oligodendrocytes (oligodendrogliomas). When these two tumor types are well differentiated it is relatively ease to differentiate one from the other, however the distinction may be difficult in more undifferentiated states or when there are mixed oligoastrocytomas. Several genetic alterations acquired during the transformation process may explain the different morphological characteristics, clinical behaviors and responses to treatments. For example LOH in 1p36 may be used to distinguish these tumor types while methylation of MGMT has been implicated in the response to therapy. Some of the Hsps may be elevated in these tumors, however the relationship of Hsp27 and Hsp70 with 1p36 status, and MGMT status has not been explored. In addition in this study we correlated the expression of these two Hsps with other molecular markers (PCNA, p53, ~-catenin) and with the tumor types and tumor grades. The study was performed on tissue blocks obtained from 44 patients with gliomas, 1p36 was evaluated by CISH, MGMT by nested PCR and IHC, and the other molecular markers by IHC. Unfortunately methylation of CpG islands in MGMT (nested PCR methylation specific) could not be done on the paraffin and/or histoplast blocks from most of the tumor tissues, then MGMT could be evaluated by IHC only. Hsp27 and Hsp70 were not useful to distinguish astrocytomas from oligodendrogliomas, but LOH in 1p36 and MGMT status evaluated by IHC were useful. Finally, Hsp27 expression was noted more frequently in grade IV astrocytomas (glioblastomas multiforme, p=O.01). Further studies will be necessary to correlate the expression of the Hsps with the follow-up of the patients and the response to therapies.. When these two tumor types are well differentiated it is relatively ease to differentiate one from the other, however the distinction may be difficult in more undifferentiated states or when there are mixed oligoastrocytomas. Several genetic alterations acquired during the transformation process may explain the different morphological characteristics, clinical behaviors and responses to treatments. For example LOH in 1p36 may be used to distinguish these tumor types while methylation of MGMT has been implicated in the response to therapy. Some of the Hsps may be elevated in these tumors, however the relationship of Hsp27 and Hsp70 with 1p36 status, and MGMT status has not been expl