Actin typing of rhabdomyosarcomas shows the presence of the fetal and adult forms of sarcomeric muscle actin.
We analyzed actin expression in two human rhabdomyosarcomas as well as in three rhabdomyosarcomas induced in rats by the injection of nickel sulfide. All five tumors exhibited appreciable amounts of the sarcomeric alpha-actin types, in line with their myogenic differentiation. The level of these actins was particularly high in the rat tumors, which according to morphological criteria, all showed a higher degree of differentiation than the human tumors. Interestingly, in both human tumors and in two of the three rat tumors, the level of the cardiac alpha-actin type was significantly higher than that of adult skeletal muscle alpha-actin. Taken together with the results of recent reports indicating that the cardiac alpha-actin type is a marker of embryonic and fetal skeletal muscle, our findings indicate that rhabdomyosarcomas express the embryonic sarcomeric actin isoform.
Rijksuniversiteit Gent, Laboratory of Genetics, Belgium.
J
J
Vandekerckhove
M
M
Osborn
M
M
Altmannsberger
K
K
Weber
D000199:Actins / Q000032:analysis* / Q000235:genetics; D000328:Adult; D000818:Animals; D002454:Cell Differentiation; D005333:Fetus; D006801:Humans; D007223:Infant; D008297:Male; D009132:Muscles / Q000166:cytology*; D009210:Myofibrils / Q000648:ultrastructure*; D010446:Peptide Fragments / Q000032:analysis; D051381:Rats; D012208:Rhabdomyosarcoma / Q000473:pathology*; D012518:Sarcomeres / Q000648:ultrastructure*
D000199:Actins; D010446:Peptide Fragments