title: Clinico-molecular study of dedifferentiation in well-differentiated liposarcoma.
abstract: Well-differentiated liposarcoma (WD) acquires fully malignant potential when the histological progression named dedifferentiation occurs. This progression is supposed to occur in a time-dependent manner but this is still a debated issue. Clinically, the prediction of dedifferentiation for WD is very important from the therapeutic point of view. To identify genes that are predictive of dedifferentiation and to understand the mechanism of dedifferentiation, we investigated clinical information of 50 cases and studied the gene expression profiles of 36 lipomatous tumors using cDNA microarray. The clinical study showed that the dedifferentiation did not always seem to occur in a time-dependent manner. Interestingly, from the gene expression study, unsupervised hierarchical clustering analysis of well-differentiated lesions obtained from dedifferentiated liposarcoma (DD) cases that were indistinguishable from WD pathologically showed a clearly distinct gene expression pattern from WD. Using the pattern-matching program, 1687 genes including 487 known genes were identified, which discriminated WD cases from well-differentiated lipomatous lesions obtained from DD cases. These results suggest that the dedifferentiation may arise from different types of WD that could be distinguished from gene expression profiling but could hardly be classified by the pathological studies.
authors.affiliation: Department of Orthopedic Surgery, Tokyo Medical and Dental University, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Shimoji
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kanda
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Kitagawa
authors.forename: Koji
authors.initials: K
authors.lastname: Kadota
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Asai
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Takahashi
authors.forename: Noriyoshi
authors.initials: N
authors.lastname: Kawaguchi
authors.forename: Seiichi
authors.initials: S
authors.lastname: Matsumoto
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Hayashizaki
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Okazaki
authors.forename: Kenichi
authors.initials: K
authors.lastname: Shinomiya
mesh_terms: D001483:Base Sequence; D002454:Cell Differentiation; D016000:Cluster Analysis; D017931:DNA Primers; D018076:DNA, Complementary; D020869:Gene Expression Profiling; D006801:Humans; D008080:Liposarcoma / Q000235:genetics / Q000473:pathology*; D020411:Oligonucleotide Array Sequence Analysis
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary