229 research outputs found
Effect of bone decalcification procedures on DNA in situ hybridization and comparative genomic hybridization. EDTA is highly preferable to a routinely used acid decalcifier
Decalcification is routinely performed for histological studies of
bone-containing tissue. Although DNA in situ hybridization (ISH) and
comparative genomic hybridization (CGH) have been successfully employed on
archival material, little has been reported on the use of these techniques
on archival decalcified bony material. In this study we compared the
effects of two commonly used decalcifiers, i.e. , one proprietary,
acid-based agent (RDO) and one chelating agent (EDTA), in relation to
subsequent DNA ISH and CGH to bony tissues (two normal vertebrae, six
prostate tumor bone metastases with one sample decalcified by both EDTA
and RDO). We found that RDO-decalcified tissue was not suited for DNA ISH
in tissue sections with centromere-specific probes, whereas we were able
to adequately determine the chromosomal status of EDTA-decalcified
material of both control and tumor material. Gel electrophoresis revealed
that no DNA could be successfully retrieved from RDO-treated material.
Moreover, in contrast to RDO-decalcified tumor material, we detected
several chromosomal imbalances in the EDTA-decalcified tumor tissue by CGH
analysis. Furthermore, it was possible to determine the DNA ploidy status
of EDTA- but not of RDO-decalcified material by DNA flow cytometry.
Decalcification of bony samples by EDTA is highly recommended for
application in DNA ISH and CGH techniques
Molecular cytogenetic evaluation of gastric cardia adenocarcinoma and precursor lesions
Analyses of cancer incidence data in the United States and Western Europe
revealed steadily rising rates over the past decades of adenocarcinomas of
the esophagus and gastric cardia. Genetic information on gastric cardia
adenocarcinoma and its preneoplasias is sparse. We have used comparative
genomic hybridization to obtain a genome-wide overview of 20 archival
gastric cardia adenocarcinomas and 10 adjacent preneoplastic lesions (
Comparative genomic hybridization of cancer of the gastroesophageal junction: deletion of 14Q31-32.1 discriminates between esophageal (Barrett's) and gastric cardia adenocarcinomas
Incidence rates have risen rapidly for esophageal and gastric cardia
adenocarcinomas. These cancers, arising at and around the gastroesophageal
junction (GEJ), share a poor prognosis. In contrast, there is no consensus
with respect to clinical staging resulting in possible adverse effects on
treatment and survival. The goal of this study was to provide more insight
into the genetic changes underlying esophageal and gastric cardia
adenocarcinomas. We have used comparative genomic hybridization for a
genetic analysis of 28 adenocarcinomas of the GEJ. Eleven tumors were
localized in the distal esophagus and related to Barrett's esophagus, and
10 tumors were situated in the gastric cardia. The remaining seven tumors
were located at the junction and could not be classified as either
Barrett-related, or gastric cardia. We found alterations in all 28
neoplasms. Gains and losses were distinguished in comparable numbers.
Frequent loss (> or = 25% of all tumors) was detected, in decreasing order
of frequency, on 4pq (54%), 14q (46%), 18q (43%), 5q (36%), 16q (36%), 9p
(29%), 17p (29%), and 21q (29%). Frequent gain (> or = 25% of all tumors)
was observed, in decreasing order of frequency, on 20pq (86%), 8q (79%),
7p (61%), 13q (46%), 12q (39%), 15q (39%), 1q (36%), 3q (32%), 5p (32%),
6p (32%), 19q (32%), Xpq (32%), 17q (29%), and 18p (25%). Nearly all
patients were male, and loss of chromosome Y was frequently noted (64%).
Recurrent high-level amplifications (> 10% of all tumors) were seen at
8q23-24.1, 15q25, 17q12-21, and 19q13.1. Minimal overlapping regions could
be determined at multiple locations (candidate genes are in parentheses):
minimal regions of overlap for deletions were assigned to 3p14 (FHIT,
RCA1), 5q14-21 (APC, MCC), 9p21 (MTS1/CDKN2), 14q31-32.1 (TSHR), 16q23,
18q21 (DCC, P15) and 21q21. Minimal overlapping amplified sites could be
seen at 5p14 (MLVI2), 6p12-21.1 (NRASL3), 7p12 (EGFR), 8q23-24.1 (MYC),
12q21.1, 15q25 (IGF1R), 17q12-21 (ERBB2/HER2-neu), 19q13.1 (TGFB1, BCL3,
AKT2), 20p12 (PCNA), 20q12-13 (MYBL2, PTPN1), and Xq25. The distribution
of the imbalances revealed similar genetic patterns in the three GEJ tumor
groups. However, loss of 14q31-32.1 occurred significantly more frequent
in Barrett-related adenocarcinomas of the distal esophagus, than in
gastric cardia cancers (P = 0.02). The unclassified, "pure junction" group
displayed an intermediate position, suggesting that these may be in part
gastric cardia tumors, whereas the others may be related to
(short-segment) Barrett's esophagus. In conclusion, this study has, fist,
provided a detailed comparative genomic hybridization-map of GEJ
adenocarcinomas documenting new genetic changes, as well as candidate
genes involved. Second, genetic divergence was revealed in this poorly
understood group of cancers
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