METASTATIC HUMAN RHABDOMYOSARCOMA - MOLECULAR, CELLULAR AND CYTOGENETIC ANALYSIS OF A NOVEL CELLULAR-MODEL

A new human metastatic rhabdomyosarcoma (RMS) model was established an d analyzed for a number of biologic, cytogenetic and molecular paramet ers. Consistent with previous studies, the metastatic capacity of diff erent RMS cell variants did not correlate with their tumorigenic or pr oliferative capacities. Interestingly, a highly metastatic variant was diploid, while a nonmetastatic variant was tetraploid, which parallel s previous clinical observations. Genes whose expression had been foun d to be associated with either low-or high-metastatic capacity in carc inoma or melanoma did not show a similar association with different me tastatic variants of RMS, derived from a mesenchymal tumor. We also fo und, in transient reporter gene assays, that several promoters had hig her transcriptional activity in highly metastatic than in nonmetastati c RMS cell variants. This novel human RMS metastatic model may be inst rumental for a better understanding of the regulatory pathways that co ntrol the metastatic phenotype of tumors of mesenchymal origin.