RESUMEN
BACKGROUND: The prognosis of patients with osteosarcoma has considerably improved over the last 30 years, mainly due to developments in chemotherapy. However, almost half of the osteosarcomas do not respond to chemotherapy. Predictive markers for chemosensitivity at diagnosis are desirable. PATIENTS AND METHODS: In order to investigate the potential of some chemotherapy-associated genes with respect to their predictive value for chemosensitivity, the mRNA expression of 8 genes was evaluated in the osteosarcomas of 45 patients and correlated to the histological response to neoadiuvant chemotherapy. RESULTS: ERCC4, a member of the nucleotide excision repair system, showed a orrelation between expression and the histologically evaluated response to chemotherapy. The expression of the other investigated genes HER-2/neu, HSP 70, GST, DHFR, BCRP, ERCC1 and Mlh1 showed no significant correlation to response to chemotherapy. CONCLUSION: In our retrospective analyses, low expression of ERCC4 was shown to be related to poor response to chemotherapy. The potential value of ERCC4 as response predictor has to be investigated in a prospective study.