Distinct Chromosomal Profiles in Metastasizing and Non-Metastasizing Colorectal Carcinomas

Abstract

The prognosis of colorectal cancer patients is to a considerable extent determined by the metastatic potency of the primary tumor. However, despite the fact that liver metastases are the leading cause of death for cancer patients, the molecular basis still remains poorly understood and independent prognostic markers have not been established.
Comparative genomic hybridization (CGH) was used to screen colorectal carcinomas without distant metastases (n=18) and carcinomas synchronously metastatic to the liver (n=18). We aimed to detect distinct chromosomal aberrations indicating a metastatic phenotype.
Metastatic tumors exhibited a significantly (P=0.03) higher ANCA value (13.8) if compared with non-metastatic cancers (10.0). Furthermore, we observed that losses of chromosomal regions 1p32-ter and 9q33-ter were present at much higher frequencies in metastatic than in non-metastatic cancers, respectively (P=0.02 and 0.04).
These data indicate that metastatic tumors may be separated from non-metastatic colorectal cancers based on their genomic profile.

Full text

Cellular Oncology 28 (2006) 273–281 273
IOS Press
Distinct chromosomal profiles in
metastasizing and non-metastasizing
colorectal carcinomas
B. Michael Ghadimi
a,∗
,MarianGrade
a
, Carsten Mönkemeyer
a
, Bettina Kulle
b
, Jochen Gaedcke
a
,
Bastian Gunawan
c
, Claus Langer
a
, Torsten Liersch
a
and Heinz Becker
a
a
Department of General Surgery, University Medical Center, Göttingen, Germany
b
Department of Genetic Epidemiology, University Medical Center, Göttingen, Germany
c
Department of Pathology, University Medical Center, Göttingen, Germany
Abstract. Background: The prognosis of colorectal cancer patients is to a considerable extent determined by the metastatic
potency of the primary tumor. However, despite the fact that liver metastases are the leading cause of death for cancer patients,
the molecular basis still remains poorly understood and independent prognostic markers have not been established. Materials
and methods: Comparative genomic hybridization (CGH) was used to screen colorectal carcinomas without distant metastases
(n = 18) and carcinomas synchronously metastatic to the liver (n = 18). We aimed to detect distinct chromosomal aberrations
indicating a metastatic phenotype. Results and discussion: Metastatic tumors exhibited a significantly (P = 0.03) higher ANCA
value (13.8) if compared with non-metastatic cancers (10.0). Furthermore, we observed that losses of chromosomal regions 1p32-
ter and 9q33-ter were present at much higher frequencies in metastatic than in non-metastatic cancers, respectively (P = 0.02
and 0.04). Conclusion: These data indicate that metastatic tumors may be separated from non-metastatic colorectal cancers based
on their genomic profile.
Keywords: Colorectal cancer, comparative genomic hybridization, liver metastases, predictive marker, prognosis
Abbreviations: UICC, International Union against
Cancer; CGH, comparative genomic hybridization;
ANCA, average number of chromosomal copy alter-
ations.
1. Introduction
The stepwise progression of colorectal carcinomas
is accompanied by gains of chromosomes 7, 8q, 13
and 20, as well as losses of chromosomes 4, 8p and
18q [9,20,28,36]. In a previous study we demonstrated
that gains of chromosome 8q23-24 are associated with
lymph node positivity in non-metastatic colorectal car-
cinomas [16]. Whereas this aberration was detected in
the vast majority of lymph node positive tumors, it was
only rarely present in lymph node negative carcinomas
*
Corresponding author: B. Michael Ghadimi, MD, Department
of General Surgery, Georg-August-University Göttingen, Robert-
Koch-Str. 40, 37099 Göttingen, Germany. E-mail: mghadim@
uni-goettingen.de.
suggesting that genes located at 8q23-24 might favor
the development of lymphatic metastases in colorectal
cancers. Regarding metastatic disease, i.e. tumors with
systemic spread, several investigators evaluated the un-
derlying genomic changes of advanced colorectal can-
cers. But the results remain contradictory, and a chro-
mosomal aberration based metastatic genotype has not
been established [2–4,6,10,24,25,31,33].
From the clinical point of view, a significant num-
ber of colorectal cancer patients develop distant metas-
tases, preferably to the liver, even though approxi-
mately 60% to 70% of these patients will undergo po-
tential curative surgery at the time of cancer diagno-
sis [39]. Therefore, adjuvant chemotherapy is widely
considered as the gold standard for patients with UICC
stage III colon cancer, who are at high risk of recur-
rence [1,8]. Nevertheless, even stage II tumors have
the potential to form distant metastases, and approxi-
mately 20% of these patients die of recurrent disease
[29]. Prospective randomized trials have therefore been
initiated to evaluate the potential benefit of adjuvant
1570-5870/06/$17.00  2006 – IOS Press and the authors. All rights reserved

274 B.M. Ghadimi et al. / Distinct chromosomal profiles in colorectal carcinomas
chemotherapy for stage II colon cancer patients. Ac-
cordingly, accurate predictive biomarkers would help
to establish an individualized, metastatic phenotype-
based therapy [18].
The aim of the present study was to investigate
distinct patterns of copy number alterations in ad-
vanced colorectal cancers. We therefore used compar-
ative genomic hybridization (CGH) to determine ge-
nomic differences between non-metastatic colorectal
cancers (mainly UICC III) and cancers synchronously
metastatic to the liver (UICC stage IV) in an attempt to
identify chromosomal aberrations that might serve as
genetic markers for the risk of liver metastases.
2. Materials and methods
2.1. Materials
In the present study, we prospectively collected sur-
gical specimens from 36 patients diagnosed with a
colorectal cancer between 2000 and 2002. Only fresh
frozen tumor samples with a tumor cell content of at
least 70% (established on hematoxylin–eosin-stained
tissue sections) were analyzed. The histopathological
classification was based on the WHO histological typ-
ing of colorectal cancers [38]. The clinical data are
summarized in Table 1. All tumors were adenocarcino-
mas and have been classified as either non-metastatic
carcinomas (group 1; pT2-4 pN0-2 M0; n = 18) or as
cancers with hepatic metastases (group 2; pT2-4 pN0-
2M1;n = 18). We only selected cancer patients ex-
hibiting liver metastases synchronously, defined as di-
agnosed within 6 months following diagnosis of the
primary tumor.
2.2. Comparative genomic hybridization
CGH experiments and analysis were performed
as previously described [15]. Briefly, CGH was per-
formed on normal, sex-matched metaphase chromo-
somes prepared according to standard procedures fol-
lowing the criteria by du Manoir and colleagues
[13]. Normal DNA was labeled in a standard nick-
translation reaction substituting dTTP with digoxi-
genin-12-dUTP (Roche; Mannheim, Germany). Tumor
DNA was extracted using a commercially available
DNA-isolation KIT from Qiagen (Hilden, Germany)
and labeled by substituting dTTP with biotin-16-dUTP
(Roche; Mannheim, Germany).
For CGH, 300 ng of normal digoxigenin-labeled and
300 ng of biotin-labeled tumor DNA were ethanol pre-
cipitated in the presence of 30 µg of the Cot-1 frac-
tion of human DNA (Roche; Mannheim, Germany).
The probe DNA was dried and resuspended in 10 µlof
hybridization solution (50% formamide, 2× SSC, 10%
dextran sulfate), denatured (5 minutes at 75
◦
C), and
preannealed for 1 hour at 37
◦
C. The normal metaphase
chromosomes were denatured separately (70% for-
mamide, 2× SSC) for 2 minutes at 75
◦
C. Hybridiza-
tion took place under a coverslip for 3 days at 37
◦
C.
Posthybridization steps were performed as described in
detail elsewhere [15]. Biotin-labeled tumor sequences
were detected with FITC conjugated to avidin (Vector
laboratories; Burlingame, CA), and the digoxigenin-
labeled reference DNA was visualized with antidigoxi-
genin Fab fragments conjugated to rhodamine (Roche;
Mannheim, Germany). The chromosomes were coun-
terstained with 4,6-diamidino-2-phenylindole (DAPI;
Vector Laboratories; Burlingame, CA) and embed-
ded in an antifade solution containing paraphenylene-
diamine (Sigma; St. Louis, USA).
Gray-level images were acquired for each fluo-
rochrome using a CCD camera (Sensys, Photomet-
rics, Munich, Germany) coupled to an epifluorescence
microscope (Axiovert 25, Zeiss, Jena, Germany) us-
ing sequential exposure through fluorochrome spe-
cific filters. For automated karyotyping and analy-
sis a software package was used (Quips Karyotyp-
ing/CGH; Vysis; Downer’s Grove, USA). At least
12–15 metaphases have been evaluated according to
the guidelines suggested in the ISCN 1995 [30]. The
karyograms (Figs 1 and 2) summarize the individual
CGH experiments. The lines to the left of the chromo-
somal ideograms indicate chromosomal losses (ratio of
0.8), the lines to the right chromosomal gains (ratio
of 1.2). Bold lines indicate high-level copy number in-
creases, exceeding a threshold of 1.5 (amplifications).
Genomic instability was estimated as the average
number of copy alterations (ANCA), which is deduced
by dividing the total number of chromosomal copy al-
terations in a karyogram (see Figs 1 and 2) by the num-
ber of tumors analyzed (for details see [37]).
2.3. Data analysis
We first compared the average number of chromoso-
mal aberrations (ANCA values) of the non-metastatic
and the metastatic tumors with a two-sided t-test for in-
dependent samples. In addition, Fisher’s exact test was
used to determine the potential significant influence of

B.M. Ghadimi et al. / Distinct chromosomal profiles in colorectal carcinomas 275
Table 1
Clinical data of 36 patients with colorectal cancer
Age (yrs) Sex TNM staging UICC stage Grading Localization
Group 1
28 63 F pT2 pN0 (0/23) M0 I 2 Ascending colon
27 54 M pT3 pN0 (0/25) M0 II 2 Cecum
21 60 F pT3 pN0 (0/22) M0 II 2 Rectum
20 53 M pT3 pN0 (0/14) M0 II 2 Sigmoid colon
19 67 M pT3 pN0 (0/26) M0 II 2 Sigmoid colon
23 73 M pT2 pN1 (2/16) M0 III 2 Sigmoid colon
25 81 M pT2 pN1 (1/21) M0 III 2 Sigmoid colon
31 52 M pT3 pN1 (1/33) M0 III 2 Ascending colon
35 73 M pT3 pN1 (1/32) M0 III 2 Cecum
32 54 M pT3 pN2 (19/21) M0 III 2 Rectum
24 71 M pT3 pN2 (21/55) M0 III 2 Ascending colon
30 60 M pT3 pN2 (6/13) M0 III 2 Rectum
29 66 F pT3 pN2 (5/21) M0 III 2 Ascending colon
34 68 F pT3 pN2 (14/15) M0 III 2 Rectum
33 65 F pT3 pN2 (12/12) M0 III 2 Ascending colon
26 71 M pT4 pN2 (9/19) M0 III 2 Cecum
36 65 M pT4 pN2 (4/22) M0 III 2 Rectum
22 69 F pT4 pN2 (9/21) M0 III 2 Cecum
Group 2
18 63 M pT2 pN0 (0/25) M1 IV 2 Rectum
7 67 F pT3 pN0 (0/19) M1 IV 2 Descending colon
2 65 M pT3 pN0 (0/10) M1 IV 2 Descending colon
5 66 M pT3 pN0 (0/17) M1 IV 2 Sigmoid colon
16 60 M pT3 pN0 (0/17) M1 IV 2 Rectum
15 68 M pT2 pN1 (1/20) M1 IV 2 Rectum
8 49 F pT2 pN2 (5/21) M1 IV 2 Rectum
13 65 M pT3 pN1 (3/19) M1 IV 2 Rectum
12 53 M pT3 pN1 (3/21) M1 IV 2 Rectum
6 78 M pT3 pN2 (16/27) M1 IV 2 Sigmoid colon
11 78 F pT3 pN2 (20/24) M1 IV 2 Transverse colon
3 61 F pT3 pN2 (22/40) M1 IV 2 Ascending colon
14 64 M pT3 pN2 (6/17) M1 IV 2 Rectum
10 78 F pT3 pN2 (4/30) M1 IV 2 Ascending colon
17 60 M pT3 pN2 (18/21) M1 IV 2 Rectum
9 75 F pT4 pN2 (21/26) M1 IV 2 Rectum
1 49 F pT4 pN2 (29/30) M1 IV 2 Sigmoid colon
4 50 M pT4 pN2 (9/23) M1 IV 2 Sigmoid colon

276 B.M. Ghadimi et al. / Distinct chromosomal profiles in colorectal carcinomas
Fig. 1. Karyogram of chromosomal gains and losses in 18 colorectal carcinomas without liver metastases (group 1).

B.M. Ghadimi et al. / Distinct chromosomal profiles in colorectal carcinomas 277
Fig. 2. Karyogram of chromosomal gains and losses in 18 colorectal carcinomas with synchronous liver metastases (group 2).

278 B.M. Ghadimi et al. / Distinct chromosomal profiles in colorectal carcinomas
chromosomal gains and losses on the metastatic phe-
notype. Differences with a P<0.05 were considered
statistically significant.
3. Results
CGH was used to screen for copy number changes
in 36 patients with colorectal cancer. The clinical data
for all patients are presented in Table 1.
3.1. Colorectal carcinomas without liver metastases
(group 1)
All 18 tumors displayed chromosomal imbalances.
Overall, we detected 90 gains and 90 losses, resulting
in an ANCA value of 10. Frequent gains affected re-
gions on chromosomes 7 (50%), 8q (50%), 13 (61%),
20 (83%) and X (50%). Losses of chromosomal ma-
terial frequently mapped to 8p (33%), 14 (39%), 15
(33%), 17p (33%) and 18q (72%). Amplifications lo-
calized exclusively to chromosome arm 20q. Figure 1
summarizes the chromosomal aberrations in the ana-
lyzed non-metastatic tumors.
3.2. Colorectal carcinomas with synchronous liver
metastases (group 2)
In this group of carcinomas (n = 18), we observed
an ANCA value of 13.8 (104 gains and 144 losses;
Fig. 2). DNA gains affected regions of chromosomes 7
(56%), 8q (56%), 13 (72%) and 20 (83%). High-level
copy number increases could be mapped to chromo-
somal band 5p13 and chromosome arms 7p and 20q.
Decreased values were observed for chromosomal re-
gions of 1p (61%), 4q (33%), 8p (67%), 9q (39%), 15
(39%), 16p (44%), 17p (67%), 17q (44%), 18q (67%),
19 (50%), 20p (33) and 22 (50%).
3.3. Comparison of non-metastatic and metastatic
colorectal carcinomas
The metastatic tumors displayed a higher degree of
chromosomal instability than the non-metastatic tu-
mors, which is reflected by a mean ANCA value of
13.8 in group 2 and 9.9 in group 1, respectively (P =
0.03). Additionally, UICC stage IV cancers showed
significantly more chromosomal losses (P = 0.01),
whereas no significant difference could be detected
when comparing the chromosomal gains in the two
groups (P = 0.33). Furthermore, we identified two
Fig. 3. Frequencies of sub-chromosomal imbalances in metastatic
(group 2) and non-metastatic (group 1) colorectal cancers.
distinct chromosomal losses which were present at
much higher frequencies in metastatic than in non-
metastatic cancers, losses of 1p32-ter (P = 0.02)
and 9q33-ter (P = 0.04), respectively (Fig. 3). Of
note, chromosomal gains with higher frequencies in
metastatic cancers could only be mapped to chromo-
some 5p (P = 0.05).
4. Discussion
Several investigators evaluated the genomic changes
underlying metastases formation of colorectal can-
cers using CGH, but the results remain contradic-
tory (recently reviewed in [11,19]). Analyzing primary
Dukes’ stage C and D carcinomas and correspond-
ing metastases, Al-Mulla and colleagues found that
gains of chromosome arms 17q and 6p were signif-
icantly associated with metastatic disease [3]. Nakao
and colleagues reported that primary metastatic tu-
mors showed higher frequencies of gains of 6q, 7q,
8q, 13q and 20q [31]. Some of these findings have

B.M. Ghadimi et al. / Distinct chromosomal profiles in colorectal carcinomas 279
been particularly confirmed by other groups, looking
at either primary tumors or metastases [4,10,33]. How-
ever, many authors stated that the primary tumors in-
vestigated neither showed identical nor totally differ-
ent genomic aberrations when compared with the cor-
responding metastases. Usually, the metastases con-
tained additional gains and losses [3,4,21,24,25]. This
is supported by findings from Alcock and colleagues,
who analyzed microdissected sub-regions from pri-
mary tumors and corresponding hepatic metastases.
They reported that no two samples from one case were
identical, although common changes like gains of X
and 12q as well as losses of 8p, 16p, 9p, 1q, 18q and
10q were identified [2]. Interestingly, de Angelis and
colleagues did not find any chromosomal aberration
correlated with clinical stage [9].
Accordingly, defined chromosomal aberrations that
clearly distinguish metastatic colorectal tumors from
non-metastatic tumors remain to be established. How-
ever, it is important to note that some groups analyzed
DNA from primary tumors, whereas others examined
metastases. Since tumors with a potential metastatic
phenotype should already be identified at the time of
diagnosis, i.e. at the time a biopsy is taken, we fa-
vor to analyze the genomic features of the primary tu-
mor. One could also argue that, depending on the time
of resection, metastases could potentially have accu-
mulated additional DNA changes. These aberrations
would then not mirror the genomic features of the pri-
mary tumor, but instead just be the manifestation of a
longer growth process in a selective environment.
In the present investigation, we used compara-
tive genomic hybridization (CGH) to compare non-
metastatic colorectal cancers with cancers synchro-
nously metastatic to the liver. Our analysis revealed
that both groups have certain chromosomal aberrations
in common that have been previously identified, for ex-
ample gains of 7, 8q, 13 and 20 and losses of 4, 8p,
14, 15, 17p and 18. In particular, since 62% of the
UICC stage III cancers revealed gains of chromosome
8q23-24, we could confirm our previously reported re-
sult that lymph node positive cancers show high fre-
quencies of this chromosomal aberration [16]. Addi-
tionally, this study demonstrates that metastatic tumors
showed significantly more chromosomal losses than
non-metastatic tumors (P = 0.01). Furthermore, we
identified distinct chromosomal aberrations that were
present at much higher frequencies in metastatic than
in non-metastatic cancers, such as losses of 1p32-ter
and 9q33-ter, respectively (P = 0.02 and 0.04). Most
interestingly, these chromosomal losses were present
in small metastatic tumors (pT2) as well as in locally
advanced metastatic tumors (pT4), and in lymph node
negative metastatic tumors as well as in lymph node
positive metastatic tumors. Possibly, the incidence of
these chromosomal aberrations reflects a highly ag-
gressive metastatic genotype of colorectal cancers.
Even though it is well known that aberrations of
chromosome 1p need to be interpreted with care [28],
we think it is rather unlikely that they represent techni-
cal artifacts. Firstly, in the present investigation, these
chromosomal aberrations have been predominantly de-
tected in metastatic tumors, whereas loss of 1p and
9q was a rather rare event in non-metastatic tumors.
Secondly, several studies have previously shown that
chromosome arm 1p is commonly affected in colorec-
tal adenocarcinomas. Deletions of 1p have been identi-
fied in colorectal adenocarcinomas using conventional
cytogenetics, fluorescence in situ hybridization or loss
of heterozygosity analyses, and the most frequently af-
fected region has been shown to be 1p32-p36 [5,12,
14,17,27,34,35,40]. Furthermore, deletions in specific
sub-regions of 1p have been associated with a poor
prognosis [23,32].
In summary, this analysis identified distinct chro-
mosomal losses that might separate metastatic from
non-metastatic colorectal carcinomas, losses of chro-
mosomal regions 1p32-ter and 9q33-ter, respectively.
This indicates that it might be possible to establish re-
liable markers for prediction of the metastatic pheno-
type. Furthermore, one can speculate that tumor sup-
pressor genes, which are predominantly inactivated via
allelic loss, might be more important for the develop-
ment of metastatic disease than oncogenes. CDC2L1
[7], CDC2L2 [26] and TP73 [22] represent potential
target genes on chromosome arm 1p. Obviously, these
hypotheses need to be validated in larger prospective
analyses.
Acknowledgement
This manuscript is part of the doctoral thesis of C.
Mönkemeyer.
References
[1] A.M. Abulafi and N.S. Williams, Local recurrence of colorectal
cancer: the problem, mechanisms, management and adjuvant
therapy, Br.J.Surg.81 (1994), 7–19.

280 B.M. Ghadimi et al. / Distinct chromosomal profiles in colorectal carcinomas
[2] H.E. Alcock, T.J. Stephenson, J.A. Royds and D.W. Hammond,
Analysis of colorectal tumor progression by microdissection
and comparative genomic hybridization, Genes Chromosomes
Cancer 37 (2003), 369–380.
[3] F. Al-Mulla, W.N. Keith, I.R. Pickford, J.J. Going and G.D.
Birnie, Comparative genomic hybridization analysis of primary
colorectal carcinomas and their synchronous metastases, Genes
Chromosomes Cancer 24 (1999), 306–314.
[4] H. Aragane, C. Sakakura, M. Nakanishi, R. Yasuoka, Y. Fujita,
H. Taniguchi, A. Hagiwara, T. Yamaguchi, T. Abe, J. Inazawa
and H. Yamagishi, Chromosomal aberrations in colorectal can-
cers and liver metastases analyzed by comparative genomic hy-
bridization, Int. J. Cancer 94 (2001), 623–629.
[5] G. Bardi, T. Sukhikh, N. Pandis, C. Fenger, O. Kronborg and
S. Heim, Karyotypic characterization of colorectal adenocarci-
nomas, Genes Chromosomes Cancer 12 (1995), 97–109.
[6] T.E. Buffart, J. Coffa, M.A. Hermsen, B. Carvalho, J.R. van der
Sijp, B. Ylstra, G. Pals, J.P. Schouten and G.A. Meijer, DNA
copy number changes at 8q11-24 in metastasized colorectal
cancer, Cell. Oncol. 27 (2005), 57–65.
[7] B. Bunnell, L.S. Heath, D.E. Adams, J.M. Lahti and V.J. Kidd,
Elevated expression of a p58 protein kinase leads to changes
in the CHO cell cycle, Proc. Nat. Acad. Sci. U.S.A. 87 (1990),
7467–7471.
[8] A.M. Cohen, Surgical considerations in patients with cancer of
the colon and rectum, Semin. Oncol. 18 (1991), 381–387.
[9] P.M. De Angelis, O.P. Clausen, A. Schjolberg and T. Stokke,
Chromosomal gains and losses in primary colorectal carcino-
mas detected by CGH and their associations with tumour DNA
ploidy, genotypes and phenotypes, Br.J.Cancer80 (1999),
526–535.
[10] C.B. Diep, L.A. Parada, M.R. Teixeira, M. Eknaes, J.M. Nes-
land, B. Johansson and R.A. Lothe, Genetic profiling of col-
orectal cancer liver metastases by combined comparative ge-
nomic hybridization and G-banding analysis, Genes Chromo-
somes Cancer 36 (2003), 189–197.
[11] C.B. Diep, K. Kleivi, F.R. Ribeiro, M.R. Teixeira, O.C. Lindg-
jaerde and R.A. Lothe, The order of genetic events associ-
ated with colorectal cancer progression inferred from meta-
analysis of copy number changes, Genes Chromosomes Cancer
45 (2006), 31–41.
[12] A. Di Vinci, E. Infusini, C. Peveri, A. Sciutto, R. Orecchia, E.
Geido, R. Monaco and W. Giaretti, Intratumor heterogeneity
of chromosome 1, 7, 17, and 18 aneusomies obtained by FISH
and association with flow cytometric DNA index in human col-
orectal adenocarcinomas, Cytometry 35 (1999), 369–375.
[13] S. du Manoir, O.P. Kallioniemi, P. Lichter, J. Piper, P.A.
Benedetti, A.D. Carothers, J.A. Fantes, J.M. Garcia-Sagredo, T.
Gerdes, M. Giollant et al., Hardware and software requirements
for quantitative analysis of comparative genomic hybridization,
Cytometry 19 (1995), 4–9.
[14] H. Gerdes, Q. Chen, A.H. Elahi, A. Sircar, E. Goldberg, D.
Winawer, C. Urmacher, S.J. Winawer and S.C. Jhanwar, Re-
current deletions involving chromosomes 1, 5, 17, and 18 in
colorectal carcinoma: possible role in biological and clinical
behavior of tumors, Anticancer Res. 15 (1995), 13–24.
[15] B.M. Ghadimi, D.L. Sackett, M.J. Difilippantonio, E. Schrock,
T. Neumann, A. Jauho, G. Auer and T. Ried, Centrosome
amplification and instability occurs exclusively in aneuploid,
but not in diploid colorectal cancer cell lines, and correlates
with numerical chromosomal aberrations, Genes Chromosomes
Cancer 27 (2000), 183–190.
[16] B.M. Ghadimi, M. Grade, T. Liersch, C. Langer, A. Siemer, L.
Fuzesi and H. Becker, Gain of chromosome 8q23-24 is a pre-
dictive marker for lymph node positivity in colorectal cancer,
Clin. Cancer Res. 9 (2003), 1808–1814.
[17] W. Giaretti, S. Molinu, J. Ceccarelli and C. Prevosto, Chro-
mosomal instability, aneuploidy, and gene mutations in human
sporadic colorectal adenomas, Cell. Oncol. 26 (2004), 301–
305.
[18] M. Grade, H. Becker and B.M. Ghadimi, The impact of mole-
cular pathology in oncology: The clinician’s perspective, Cell.
Oncol. 26 (2004), 275–278.
[19] M. Grade, H. Becker, T. Liersch, T. Ried and B.M. Ghadimi,
Molecular cytogenetics: Genomic imbalances in colorectal
cancer and their clinical impact, Cell. Oncol. 28 (2006), 71–84.
[20] M.A. Hermsen, C. Postma, J.P. Baak, M. Weiss, A. Rapallo, A.
Sciutto, G. Roemen, J.W. Arends, R. Williams, W. Giaretti, A.
De Goeij and G.A. Meijer, Colorectal adenoma to carcinoma
progression follows multiple pathways of chromosomal insta-
bility, Gastroenterology 123 (2002), 1109–1119.
[21] M. Iwamoto, D. Banerjee, L.G. Menon, A. Jurkiewicz, P.H.
Rao, N.E. Kemeny, Y. Fong, S.C. Jhanwar, R. Gorlick and J.R.
Bertino, Overexpression of E2F-1 in lung and liver metastases
of human colon cancer is associated with gene amplification,
Cancer Biol. Ther. 3 (2004), 395–399.
[22] C.A. Jost, M.C. Marin and W.G. Kaelin Jr., p73 is a human p53-
related protein that can induce apoptosis, Nature 389 (1997),
191–194.
[23] T. Kambara, G.B. Sharp, T. Nagasaka, M. Takeda, H.
Sasamoto, H. Nakagawa, H. Isozaki, D.G. MacPhee, J.R. Jass,
N. Tanaka and N. Matsubara, Allelic loss of a common mi-
crosatellite marker MYCL1: a useful prognostic factor of poor
outcomes in colorectal cancer, Clin. Cancer Res. 10 (2004),
1758–1763.
[24] T. Knösel, S. Petersen, H. Schwabe, K. Schluns, U. Stein, P.M.
Schlag, M. Dietel and I. Petersen, Incidence of chromosomal
imbalances in advanced colorectal carcinomas and their metas-
tases, Virchows Arch. 440 (2002), 187–194.
[25] W.M. Korn, T. Yasutake, W.L. Kuo, R.S. Warren, C. Collins,
M. Tomita, J. Gray and F.M. Waldman, Chromosome arm
20q gains and other genomic alterations in colorectal cancer
metastatic to liver, as analyzed by comparative genomic hy-
bridization and fluorescence in situ hybridization, Genes Chro-
mosomes Cancer 25 (1999), 82–90.
[26] J.M. Lahti, M. Valentine, J. Xiang, B. Jones, J. Amann, J.
Grenet, G. Richmond, A.T. Look and V.J. Kidd, Alterations
in the PITSLRE protein kinase gene complex on chromosome
1p36 in childhood neuroblastoma, Nature Genet. 7 (1994),
370–375.
[27] I. Leister, A. Weith, S. Bruderlein, C. Cziepluch, D. Kangwan-
pong, P. Schlag and M. Schwab, Human colorectal cancer: high
frequency of deletions at chromosome 1p35, Cancer Res. 50
(1990), 7232–7235.
[28] G.A. Meijer, M.A. Hermsen, J.P. Baak, P.J. van Diest, S.G.
Meuwissen, J.A. Belien, J.M. Hoovers, H. Joenje, P.J. Sni-

B.M. Ghadimi et al. / Distinct chromosomal profiles in colorectal carcinomas 281
jders and J.M. Walboomers, Progression from colorectal ade-
noma to carcinoma is associated with non-random chromoso-
mal gains as detected by comparative genomic hybridization,
J. Clin. Pathol. 51 (1998), 901–909.
[29] R. Midgley and D. Kerr, Colorectal cancer, Lancet 353 (1999),
391–399.
[30] F. Mitelman, ISCN. An International System for Human Cyto-
genetic Nomenclature, S. Karger, Basel, 1995.
[31] K. Nakao, M. Shibusawa, A. Ishihara, H. Yoshizawa, A. Tsun-
oda, M. Kusano, A. Kurose, T. Makita and K. Sasaki, Genetic
changes in colorectal carcinoma tumors with liver metastases
analyzed by comparative genomic hybridization and DNA
ploidy, Cancer 91 (2001), 721–726.
[32] O.A. Ogunbiyi, P.J. Goodfellow, G. Gagliardi, P.E. Swanson,
E.H. Birnbaum, J.W. Fleshman, I.J. Kodner and J.F. Moley,
Prognostic value of chromosome 1p allelic loss in colon cancer,
Gastroenterology 113 (1997), 761–766.
[33] A. Paredes-Zaglul, J.J. Kang, Y.P. Essig, W. Mao, R. Irby, M.
Wloch and T.J. Yeatman, Analysis of colorectal cancer by com-
parative genomic hybridization: evidence for induction of the
metastatic phenotype by loss of tumor suppressor genes, Clin.
Cancer Res. 4 (1998), 879–886.
[34] C. Praml, L.H. Finke, C. Herfarth, P. Schlag, M. Schwab and L.
Amler, Deletion mapping defines different regions in 1p34.2-
pter that may harbor genetic information related to human col-
orectal cancer, Oncogene 11 (1995), 1357–1362.
[35] G. Ragnarsson, G. Eiriksdottir, J.T. Johannsdottir, J.G. Jonas-
son, V. Egilsson and S. Ingvarsson, Loss of heterozygosity at
chromosome 1p in different solid human tumours: association
with survival, Br.J.Cancer79 (1999), 1468–1474.
[36] T. Ried, R. Knutzen, R. Steinbeck, H. Blegen, E. Schröck, K.
Heselmeyer, S. du Manoir and G. Auer, Comparative genomic
hybridization reveals a specific pattern of chromosomal gains
and losses during the genesis of colorectal tumors, Genes Chro-
mosomes Cancer 15 (1996), 234–245.
[37] T. Ried, K. Heselmeyer-Haddad, H. Blegen, E. Schrock and
G. Auer, Genomic changes defining the genesis, progression,
and malignancy potential in solid human tumors: a pheno-
type/genotype correlation, Genes Chromosomes Cancer 25
(1999), 195–204.
[38] L.H. Sobin and C. Wittekind, UICC: TNM Classification of
Malignant Tumors, 5th edn, John Wiley & Sons, New York,
1997.
[39] G. Steele Jr. and T.S. Ravikumar, Resection of hepatic metas-
tases from colorectal cancer. Biologic perspective, Ann. Surg.
210 (1989), 127–138.
[40] L. Thorstensen, H. Qvist, S. Heim, G.J. Liefers, J.M. Nesland,
K.E. Giercksky and R.A. Lothe, Evaluation of 1p losses in pri-
mary carcinomas, local recurrences and peripheral metastases
from colorectal cancer patients, Neoplasia 2 (2000), 514–522.