Molecular genetic, cytogenetic, and immunohistochemical characterization of alveolar soft-part sarcoma. Implications for cell of origin.
BACKGROUND
Alveolar soft-part sarcoma is a rare tumor of uncertain histogenesis.


METHODS
The authors report a patient who was studied using immunohistochemistry, cytogenetic analysis, and molecular probes for MyoD1 and MYCN (N-myc proto-oncogene).


RESULTS
By immunoperoxidase, the tumor was focally positive for vimentin, neuron-specific enolase, and S-100 protein but negative for muscle-specific actin, desmin, and low-molecular-weight keratin. Direct chromosome analysis of primary tumor cells using G-banded preparations yielded two clonally abnormal lines: one demonstrated trisomy 47,XX+5; the other demonstrated 46,XX,1p-,17q+. Expression of the MYCN RNA was detectable at a low level, and MYCN was single copy at the DNA level. Expression of the myogenic molecular marker MyoD1 was not detected by Northern blotting analysis.


CONCLUSIONS
This is the first detailed study to address the molecular biology and tumor cytogenetics of alveolar soft-part sarcoma. The results of this study indicate a neurogenic origin for this unusual tumor and fail to provide support for the notion of a myogenic origin.
Cullinane
C
C
Department of Pathology, Hospital for Sick Children, Toronto, Ontario, Canada.
Thorner
P S
PS
Greenberg
M L
ML
Kwan
Y
Y
Kumar
M
M
Squire
J
J
D000293:Adolescent; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D015870:Gene Expression; D016259:Genes, myc; D006801:Humans; D007150:Immunohistochemistry; D007621:Karyotyping; D000090063:Proto-Oncogene Mas; D012334:RNA, Neoplasm / Q000032:analysis; D012509:Sarcoma / Q000209:etiology / Q000235:genetics* / Q000276:immunology / Q000473:pathology*; D012983:Soft Tissue Neoplasms / Q000209:etiology / Q000235:genetics* / Q000276:immunology / Q000473:pathology*
D004273:DNA, Neoplasm; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D012334:RNA, Neoplasm