Expression of Heat Shock Proteins in Osteosarcomas
A Moon, P Bacchini, F Bertoni, YW Kim, YK Park. Kyung Hee Univercity, Seoul, Republic of Korea; Villa Erbosa Hospital, Bologna, Italy; Rizzoli Institute, Univercity of Bologna, Bologna, Italy
Background: Heat shock proteins (HSPs) protect cells against stress-associated injury and are overexpressed in several malignant tumors. We aimed to investigate the potential role of HSP27, HSP60 and HSP70 in conventional and low grade central osteosarcoma (OSA).
Design: Expression of HSP27, HSP60 and HSP70 was analyzed using immunohistochemistry on tissue section from 52 cases of conventional OSA and 21 cases of low grade central OSA. Conventional OSA consisted of osteoblastic (n=45) and non-osteoblastic [chondroblastic (n=4), fibroblastic (n=2) and telangiectatic (n=1)]. We evaluated the expression of each protein and examined its relationship with clinicopathologic parameters.
Results: We classified the cases in which more than 10% of tumor cells were positive into the high expression group. The high expression rate in osteoblastic conventional OSA was 28.9% (HSP27), 93.3% (HSP60) and 88.9% (HSP70). The rate in non-osteoblastic conventional OSA was 71.4% (HSP27), 85.7% (HSP60) and 85.7% (HSP70). The high expression rate in low grade central OSA was 4.8% (HSP27), 85.7% (HSP60) and 14.3% (HSP70). The expression of HSP27 and HSP70 in conventional OSA was significantly higher than that in low grade central OSA (P=0.008 and 0.001, respectively). In conventional OSA, higher expression of HSP27 was significantly related to distant metastasis (P=0.034) and histological subtype [osteoblastic vs. non-osteoblastic (P=0.041)]. The expression of HSP60 and HSP70 was not significantly related to any clinicopathologic parameters.
Conclusions: HSP70 and HSP27 may be used as a differential marker to distinguish conventional OSA and low grade central OSA. HSP 27 may be used as a possible prognostic marker in conventional osteosarcoma cases.
Category: Bone & Soft Tissue
Tuesday, March 23, 2010 9:30 AM
Poster Session III # 16, Tuesday Morning