Chromosome 12 breakpoints are cytogenetically different in benign and malignant lipogenic tumors: localization of breakpoints in lipoma to 12q15 and in myxoid liposarcoma to 12q13.3.
Cytogenetic study of short-term cultures from 10 adipose tissue tumors (eight lipomas, one myxoid liposarcoma, and one mixed liposarcoma) have revealed clonal chromosome abnormalities in seven cases. In both malignant tumors, translocation (12;16) was the sole aberration, and in the mixed liposarcoma, the breakpoints could be sublocalized to bands 12q13.3 and 16p11.2, thus confirming findings of Eneroth et al., Cancer Genet. Cytogenet., 48: 101-107, 1990. Three lipomas displayed predominantly normal karyotypes; in a fourth case, the karyotype 44,XX,-6,der (7)t(6;7)(p21.3-22;p22)ins(7)(p22q11.2q22),-13 was found. Four remaining lipomas were characterized by structural rearrangements of chromosome 12. We were able to achieve high resolution banding patterns in two tumors with translocations (3;12)(q28;q15) and (1;2;12)(p36.;q13;q15). In both of these cases, the chromosome 12 breakpoint could be unequivocally assigned to band q15. Similarly, band 12q15 was also rearranged in two other lipomas with translocations (12;14)(q15;q32) and (12;20)(q15;q13.1). Our results support the hypothesis that the chromosome 12 breakpoint in lipomas is located more distally than the breakpoint in myxoid liposarcomas and some other soft-tissue malignant neoplasms and that it is cytogenetically identical with breakpoints detected in such benign tumors as uterine leiomyoma and pleomorphic adenoma of the salivary gland.
Mrózek
K
K
Cytogenetics Research Laboratory, Roswell Park Cancer Institute, Buffalo, New York 14263.
Karakousis
C P
CP
Bloomfield
C D
CD
D000328:Adult; D000368:Aged; D002871:Chromosome Banding; D002878:Chromosomes, Human, Pair 1; D002881:Chromosomes, Human, Pair 12; D002883:Chromosomes, Human, Pair 14; D002885:Chromosomes, Human, Pair 16; D002890:Chromosomes, Human, Pair 20; D002893:Chromosomes, Human, Pair 3; D002897:Chromosomes, Human, Pair 7; D005260:Female; D006801:Humans; D007621:Karyotyping; D008067:Lipoma / Q000235:genetics*; D008080:Liposarcoma / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D012878:Skin Neoplasms / Q000235:genetics*; D014178:Translocation, Genetic