Abstracts RING CHROMOSOMES [Is[ DERMATOFIBROSARCOMA P R O T U B E R A N S C O N T A I N C H R O M O S O M E 17 S E Q U E N C E S : FISH A N A L Y S I S OF T W O CASES
Pedeumm F.. Coindre J.M. Nicolo G.. Boucho( C., Aytaud N.. TurcCarelC.. Laboraloirede G~n~tiqueMoi6cullire des Cance~lHumtinl.
URA CNRS1462.Unive~itt de Nice.Nice.France(F.P.C.B.N.A.C.T-C).
Laboratotre d'Anammo-Pathologi¢, Fondation Bergon~, Bordeaux. France (JMC). Laborltorio di Cistoislologie Patologica. lnstitutoNazionale per |a Ric=rca =tul Cancro, Genovt. 1Udy (GN), Demmtofitwosarcoma ixotubefans (DP) is an uncommoa low grade, slow growing and locally aggressive tumor of the deep dermis considered to be related to fihrohisriocytic tumoct. The common cytogenetic feature of the five previously described cases w&s the preseace of one ~ two supemumeraw ring chmmoanmes as the sole cytogeaetic abn~atafity o¢ in essociatioa with Chromosome changes. We report here two new DP cases wire ring c h m m o t 0 m ~ which were analyzed by F[SH using centrometic and Whole Chromosome Painting OVCP)probes.
Convemiommicytog~eticsdatashowedthe followingkaryotypcs: 49. XX. +5. +8. +r and 46.XY. der(5) t(5;13)(pil;qll). -13. der(17)t(17;?Xpl3;?), -18, +r in the Sl~'uaen T91125 and T91127 respeai~y. FISH experimcals showed [ha[ I) while the origin of the o~l~romere of the ttng from T9 i 125 remained ~ l ' m d L the ceaw0mesea of the di. and tricentric rings from T91127 were donated by chromosome 17 2) the nng chromosome in both samples coatained sequences of chromosome 17, However, the chromosome 17 seque,aces were diffefendy disuilmted. Wieh the WCP DNA probefm cl0uromo~3me 17, the ring chromo¢,ome from T91125 showednan'ow positive bands alternating with unlmown malP~alwhile all the rings from T91127 w e ~ homogeaeou~y minted. in stan, daromosome 17sequeaces were ideatified in the supemmnerary rings in both cases of DP. Many questmns remmn. Do the rings aho o 4 ~ e d in m o ~ aggresuve fibrihistiocytic tumors, the malignant fibrous hisliocyt0mas, contain chromosome 17 sequencessimilafy to DP ? What proportionof DP cases bare extra chromosome 17 se4ueuces?Wbai s4pecific genes are involved? Which role do they play in tl~ pathogeaesis of DP?
HIGH RESOLUTION CYTOGENETIC STUDY OF ADIPOSE "rlSSUE TUMORS: LOCALIZATION OF CHROMOSOME 12 BFIEAKPOINTSIN ~ TO Q15 AND IN MYXOID UPOSARCOMA TO Q13.3
Krzysz'tof Mrbzek1, Constantine P. KarakocJsis and Clara D. Bloomfmld. Cytoganetics Research Laboratory (K.M.), Departments of Medicine (C.D.B., K.M.) and Surgical Oflcology (C.P.K.), RosweUPark Cancer Institute, Buffalo, NY. 1Permanent address: Department of Biology end Genetics, Medical Academy, Gda~k, Poland. Cytogenetic study of short-term cultures from ten adipose tissue tumors - eight lipomas, one myxoid and orm mixed (myxoid and round cell) liposarcoma - have revealed clonal chromosome abnormalities in seven cases, in both malignant tumors transiocation (12;16) was the sole Id0errdon end in the mixed lipo~mrcoma the b r e a k ~ could be s ~ to bands 12q13.3 and 16p11.2, thus c o n ~ f l n d ~ of Eneroth et al. (Cancer Ganet Cyqogenet 1990, 48:101-107). Three lipornes displayed predominantly normal karyotyp~; in It fourth case the karyotype 44,XX,-6,der (7)lns(7)(p22ql 1.2q22)t(6;7)(p21.322;1:~2),-13 was found. Four lipomas were characterized by structural rearrangements of c h r ~ 12. We were able to achieve high resolution banding patterns in two tumonl with t(3;12)(q28;q15) and t(1;2;12)(p36.1;q13;q15), respectively, in both of these cases, the chromosome 12 ~ t could be unequivocally assigned to band ql 5. Similarly, band 12ql 5 was also rearranged in two other lipomas with t(12;14)(qlS;q32) and t(12;20)(ql 5;ql 3.1). Our results support the hypoUle~l that the chromosome 12 breakpoint in lipomas is located mote distally than the breakpoint in myxotd liposarcomas and that it is cytogenetically identical to b r e a k ~ detected in other benign tumocs, i.e., uterine leiomyomas and pleomorphlc edenomas of the salivary gland. Supported by the Coleman Leukemia Research Fund and NIH Grant CA-16056.