[Changes in the LDH isoenzyme spectrum in transplantable rhabdomyosarcoma clones transplanted into the anterior chamber of the eye].

Results of gel electrophoresis of transplantable rat (RA-2) and murine (MC-53) rhabdomyosarcomas show that the LDH isoenzyme spectrum of tumors growing subcutaneously differ from that of normal muscle tissue, LDH-1 and LDH-2 isoenzyme being absent in zymograms. Using the lung colony formation technique, clones of RA-2 and MC-53 were obtained and their zymograms were investigated. Clone populations of both the tumors were polymorphic for their LDH spectrum, in some clones of RA-2 normal LDH isoenzyme spectrum was found. After a 16-18 day cultivation in rat and mouse eye anterior chamber, LDH spectra of RA-2 and MC-53 clones changed sharply, LDH-1 and LDH-2 appearing. As a result, LDH isoenzyme spectra of some clones that grew in the eye anterior chamber became equal to those of the normal muscle tissue. The observed changes are discussed as biochemical signs of cytodifferentiation of tumor cells.