Trail-induced apoptosis and interaction with cytotoxic agents in soft tissue sarcoma cell lines.

Five human soft tissue sarcoma (STS) cell lines (HTB-82 rhabdomyosarcoma, HTB-91 fibrosarcoma, HTB-92 liposarcoma, HTB-93 synovial sarcoma and HTB-94 chondrosarcoma) were analysed for their sensitivity to tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and the function of the TRAIL apoptotic pathway in these cells. TRAIL induced significant apoptosis (>90%) in HTB-92 and HTB-93 cells, whereas no effect was observed in HTB-82, HTB-91 and HTB-94 cells. TRAIL-Receptor 1 (TRAIL-R1) was expressed in TRAIL-sensitive HTB-92 and HTB-93 cell lines, but not in TRAIL-resistant HTB-91 and HTB-94 cells.

Cyclophilin A, the major intracellular receptor for the immunosuppressant cyclosporin A, maps to chromosome 7p11.2-p13: four pseudogenes map to chromosomes 3, 10, 14, and 18.

Cyclophilin A (CyP-A), the major intracellular receptor for the immunosuppressant cyclosporin A (CsA), is a member of the immunophilin class of proteins, which all possess peptidyl-prolyl cis-trans isomerase activity and, therefore, are believed to be involved in protein folding and/or intracellular protein transport. The CyP-A protein is encoded by a single gene; in addition, 15 pseudogenes have been identified. Recently, specific binding of CyP-A to the human immunodeficiency virus type 1 (HIV-1) gag protein has been reported.