scholarly journals DNA copy number changes in diffuse large B-cell lymphoma--comparative genomic hybridization study

Blood ◽  
1996 ◽  
Vol 87 (12) ◽  
pp. 5269-5278 ◽  
Author(s):  
O Monni ◽  
H Joensuu ◽  
K Franssila ◽  
S Knuutila

We studied DNA copy number changes in diffuse large B-cell lymphoma using comparative genomic hybridization analysis on 20 primary tumors and on 12 recurrent tumors excised after chemotherapy or radiotherapy. Twenty-nine (91%) of the cases showed abnormal copy number karyotypes. Chromosomal regions at X (41%), 1q (38%), 7 (31%), 3 (24%), 6p (21%), 11 (21%), 12 (21%), and 18 (21%) were most frequently gained, and the most common losses involved 6q (38%), X (21%), 1p (14%), and 8p (10%). High-level amplifications were observed at 6p23-ter, 10p12–14, 17p1l.2, 18q21-ter, and Xq22-ter, all but 18q appearing only in the recurrent tumors. Gains (median, 2; range, 0 to 10) were more frequent than losses (median, 1; range, 0 to 7; P = .0004). The median number of aberrations found in the recurrent tumors (6.5) was greater than that in the primary tumors (2; P = .01). The copy number changes found in the recurrent tumors were more random than those found in the primary tumors, which were mainly located in the most frequently affected regions. Our findings are in line with those observed using conventional cytogenetic analysis, but especially novel high-level amplifications were detected. Southern blot analysis showed BCL2 amplification, but not translocation t(14;18)(q32;q21), in cases in which a gain at 18q was detected by comparative genomic hybridization, which strongly suggests that, in addition to translocation, gene amplification is another mechanism for the overexpression of the BCL2 protein.

Blood ◽  
2006 ◽  
Vol 107 (6) ◽  
pp. 2477-2485 ◽  
Author(s):  
Weiyi Chen ◽  
Jane Houldsworth ◽  
Adam B. Olshen ◽  
Gouri Nanjangud ◽  
Seeta Chaganti ◽  
...  

Abstract To identify, in high-resolution regions of DNA, the copy number changes associated with outcome in patients with diffuse large B-cell lymphoma (DLBCL), a disease with an approximately 50% mortality rate, we performed array comparative genomic hybridization (array-CGH) on specimens from 64 patients with newly diagnosed DLBCL treated with anthracycline-based chemotherapy. For the entire cohort, 55 commonly gained/lost regions, ranging in size from less than 1 Mbp to entire chromosomes, were identified using 1- to 2-Mbp and 2- to 4-Mbp resolution BAC arrays. Copy number changes of 9 minimal regions significantly correlated with overall survival, of which 6 were 10 Mbp or smaller. On multivariate analysis, loss of chromosomes 2 (2.4-4.1 Mbp) and 16 (33.8-35.6 Mbp) were found to be prognostic indicators of poor survival, independent of clinical features routinely used to predict outcome. Loss of chromosome 1 (78.2-79.1 Mbp) was predictive of good outcome. For a subset of 55 specimens classified according to cell-of-origin expression signature subtype, gain of chromosome 12 (45.4-53.8 Mbp) was found to be significantly associated with the germinal center B-cell-like DLBCL subtype. Overall, array-CGH identified relatively small genomic regions associated with outcome, which, along with follow-up expression studies, may reveal target genes important in DLBCL clinical behavior. (Blood. 2006;107:2477-2485)


2006 ◽  
Vol 24 (2) ◽  
pp. 296-305 ◽  
Author(s):  
Remco Dijkman ◽  
Cornelis P. Tensen ◽  
Ekaterina S. Jordanova ◽  
Jeroen Knijnenburg ◽  
Juliette J. Hoefnagel ◽  
...  

Purpose To evaluate the clinical relevance of genomic aberrations in primary cutaneous large B-cell lymphoma (PCLBCL). Patients and Methods Skin biopsy samples of 31 patients with a PCLBCL classified as either primary cutaneous follicle center lymphoma (PCFCL; n = 19) or PCLBCL, leg type (n = 12), according to the WHO–European Organisation for Research and Treatment of Cancer (EORTC) classification, were investigated using array-based comparative genomic hybridization, fluorescence in situ hybridization (FISH), and examination of promoter hypermethylation. Results The most recurrent alterations in PCFCL were high-level DNA amplifications at 2p16.1 (63%) and deletion of chromosome 14q32.33 (68%). FISH analysis confirmed c-REL amplification in patients with gains at 2p16.1. In PCLBCL, leg type, most prominent aberrations were a high-level DNA amplification of 18q21.31-q21.33 (67%), including the BCL-2 and MALT1 genes as confirmed by FISH, and deletions of a small region within 9p21.3 containing the CDKN2A, CDKN2B, and NSG-x genes. Homozygous deletion of 9p21.3 was detected in five of 12 patients with PCLBCL, leg type, but in zero of 19 patients with PCFCL. Complete methylation of the promoter region of the CDKN2A gene was demonstrated in one PCLBCL, leg type, patient with hemizygous deletion, in one patient without deletion, but in zero of 19 patients with PCFCL. Seven of seven PCLBCL, leg type, patients with deletion of 9p21.3 and/or complete methylation of CDKN2A died as a result of their lymphoma. Conclusion Our results demonstrate prominent differences in chromosomal alterations between PCFCL and PCLBCL, leg type, that support their classification as separate entities within the WHO-EORTC scheme. Inactivation of CDKN2A by either deletion or methylation of its promoter could be an important prognostic parameter for the group of PCLBCL, leg type.


2001 ◽  
Vol 22 (3) ◽  
pp. 159-163 ◽  
Author(s):  
Kowan J. Jee ◽  
Young Tak Kim ◽  
Kyu Rae Kim ◽  
Yan Aalto ◽  
Sakari Knuutila

DNA copy number changes were studied by comparative genomic hybridization on 10 tumor specimens of squamous cell carcinoma of cervix obtained from Korean patients. DNA was extracted from paraffin‐embedded sections after removal of non‐malignant cells by microdissection technique. Copy number changes were found in 8/10 tumors. The most frequent changes were chromosome 19 gains (n=6) and losses on chromosomes 4 (n=4), 5 (n=3), and 3p (n=3). A novel finding was amplification in chromosome arm 9p21‐pter in 2 cases. Gains in 1, 3q, 5p, 6p, 8q, 16p, 17, and 20q and losses at 2q, 6q, 8p, 9q, 10p, 11, 13, 16q, and 18q were observed in at least one of the cases.


2002 ◽  
Vol 15 (8) ◽  
pp. 807-816 ◽  
Author(s):  
Mattias Berglund ◽  
Gunilla Enblad ◽  
Emma Flordal ◽  
Weng-Onn Lui ◽  
Carin Backlin ◽  
...  

2004 ◽  
Vol 17 (5) ◽  
pp. 561-567 ◽  
Author(s):  
Marcelo L Larramendy ◽  
Virve Koljonen ◽  
Tom Böhling ◽  
Erkki Tukiainen ◽  
Sakari Knuutila

Sign in / Sign up

Export Citation Format

Share Document