Molecular cytogenetics of bone and soft tissue tumors

Many different neoplasms may arise from the various cell types that are present in human supportive tissues. The term "soft tissue tumor" is used to denote a subgroup of these neoplasms and includes synovial sarcomas, fibrosarcomas, liposarcomas, leiomyosarcomas, rhabdomyosarcomas, angiosarcomas, and the most common form, malignant fibrous histiocytomas [1]. Cytogenetic studies have revealed the occurrence of both numerical and structural abnormalities in several of these tumors, including recurrent chromosomal translocations [2-5]. In other soft tissue tumors, double minutes, ring chromosomes, and large rod-shaped markels have repeatedly been encountered. These latter anomalies appear to be associated with gene amplifications [6-8]. Also, osteosarcomas originate from supportive tissues [9]. At present, little is known about the cytogenetic :alterations that occur in these tumors or how such alterations may relate to tumor initiation and/or progression [2]. However, some studies have revealed highly aneuploid and extremely complex karyotypes with numerous cytogenetic abnormalities including, again, supernumerary ring chromosomes and double minutes [10-12]. Here, on the occasion of Dr. Avery Sandberg's 75 th birthday, the :recent molecular genetic analysis of a soft tissue tumor (synovial sarcoma)-associated chromosomal translocation and the delineation via comparative genomic hybridization of more complex cytogenetic anomalies in several other (sub) types of human bone and soft tissue tumors are discussed.