<prompt> Ewings sarcomaOsteosarcomaDermatofibrous protrubernsAlveolar cell sarcoma  <response>: Study repos on the specific expression of the MIC2 gene, a pseudoautosomal gene located on the sho arms of the X and Y chromosomes, on Ewing;s sarcoma ES and peripheral primitive neuroectodermal tumor pPNET cells. The gene product, a cell membrane protein, is recognized by the newly established monoclonal antibody MoAb HBA-71 and the previously described MoAb 12E7 and RFB-1. Fuhermore, the reaction pattern of the MIC2 antibodies, especially HBA-71, with normal tissues and a great number of benign and malignant tumors 70 different tumors, 199 tumor samples, as well as the correlation between the specific chromosomal aberrations. 