Chromosome alterations in breast carcinomas: frequent involvement of DNA losses including chromosomes 4q and 21q

Abstract

Summary Comparative genomic hybridization was applied to map DNA gains and losses in 39 invasive ductal breast carcinomas. Frequent abnormalities included gains on chromosomal regions lq, 8q, 11q12-13, 16p, 19, 20q and X as well as frequent losses on 1 p, 5q, 6q, 9p, llq, 13q and 16q. Furthermore, frequent losses on 4q (20 cases) and 21q (14 cases) were found for the first time in this tumour type. High copy number amplifications were observed at 8q12-24, 11qll-13 and 20q13-ter. Highly differentiated tumours were associated with gains on 1q and 11q12-13 along with losses on 1p21-22, 4q, 13q, 11q21-ter. Undifferentiated breast carcinomas were characterized by additional DNA imbalances, i.e. deletions of 5q13-23, all of chromosome 9, the centromeric part of chromosome 13 including band 13q14 and the overrepresentation of chromosome X. We speculate that these changes are associated with tumour progression of invasive ductal breast cancer.

Comparative Genomic Hybridization Analysis of Myoepithelial Carcinoma of the Breast

“…None of the alterations identified in myoepithelial carcinomas are unique, and they have been previously described in invasive breast carcinomas with luminal phenotype (Buerger et al, 1999;Nishizaki et al, 1997;Roylance et al, 1999;Schwendel et al, 1998;Tirkkonen et al, 1998). The most common alterations identified in myoepithelial carcinoma (loss of 16q and 17p) are also regions commonly deleted in ductal carcinomas of no special type.…”

“…The most striking observation from this study is the paucity of alterations identified in myoepithelial carcinomas (mean 2.1) compared with "ordinary" breast carcinomas having luminal differentiation. The mean number of alterations reported in the literature in Grade I invasive ductal carcinomas of no special type is 5.4 (range of means is 3.6 -8.0), and 11.7 in Grade III tumors (range of means 8.4 -13.8) (Buerger et al, 1999;Nishizaki et al, 1997;Roylance et al, 1999;Schwendel et al, 1998;Tirkkonen et al, 1998). The data in myoepithelial tumors are surprising in view of their aggressive morphology and behavior.…”

“…Although there was considerable overlap in the genetic profile of the two distinct epithelial tumor types, some of the most common alterations described in ductal carcinomas, such as gains of 1q, 8q, and 20q, and losses of 1p, 8p, and 13q (Buerger et al, 1999;Nishizaki et al, 1997;Roylance et al, 1999;Schwendel et al, 1998;Tirkkonen et al, 1998), were not identified in myoepithelial carcinomas. On the assumption that the two cell types are derived from a common stem cell (Lakhani et al, 1999), genetic alterations that overlap between luminal and myoepithelial tumors must have occurred within stem cells before differentiation into the two epithelial cell types.…”

Clinical Significance of Expression and Amplification of the DcR3 Gene in Pancreatic Carcinomas

“…DcR3 coding gene was located at human chromosome 20q13.3, which is also a site prone to gene amplification and rearrangement (Schwendel et al, 1998). However, whether the overexpression of DcR3 in tumor tissues is dependent on gene amplification is still ambiguous.…”

PRDM5 is silenced in human cancers and has growth suppressive activities

“…This gene maps to chromosome 4q25-q26. This region is commonly deleted in human breast cancer (Tirkkonen et al, 1997;Schwendel et al, 1998), ovarian cancer (Sonoda et al, 1997), lung cancer (Shivapurkar et al, 1999), hepatoma (Chou et al, 1998;Piao et al, 1998), cervical cancer (Mitra et al, 1994), head and neck squamous cell carcinoma (Pershouse et al, 1997), colon cancer (Arribas et al, 1999), and oral cancer (Wang et al, 1999). A candidate for the iris hypoplasia locus also maps on 4q25 (Heon et al, 1995).…”