Genetic and epigenetic alterations of the cell cycle regulators and tumor suppressor genes in pediatric osteosarcomas.

Purpose: To analyze the genetic and epigenetic alterations affecting the RB1, TP53, p16INK4, and p21WAF1 tumor suppressor genes, loss of heterozygosity (LOH) at 3q and 18q, and the clinical variables of a series of Spanish children with osteosarcoma. These genetic changes were tested for an association with prognosis.

Methods: Peripheral blood samples and clinical data were available from 76 patients with osteosarcoma.

Measurement and analysis of the chemotherapy-induced genetic instability in pediatric cancer patients.

Bleomycin sensitivity has been proven to be a useful biomarker for environmental carcinogenesis and tumor genetic instability. We have previously reported a significant increase in the chromosomal aberrations induced by chemotherapy regimens. This study aimed to test whether there is an inherent increased genetic instability in cancer patients at diagnosis, to determine the increase and time course of the chemotherapy-induced instability and to test whether bleomycin sensitivity can be used as a predictor of tumor evolution or relapse.