European Human Genetics Conference 2007 June 16 – 19, 2007 ...

Cancer genetics
P0518. A map of nuclear matrix attachment regions within
the breast cancer loss-of-heterozygosity region on human
chromosome 16q22.1
S. Shaposhnikov 1 , S. Akopov 2 , I. Chernov 2 , L. Nikolaev 2 , E. Frengen 3 , A. Collins
3 , V. Zverev 1 ;
1 Institute of Viral Preparations, Moscow, Russian Federation, 2 Shemyakin and
Ovchinnikov Institute of Bioorganic Chemistry, Moscow, Russian Federation,
3 University of Oslo, Oslo, Norway.
To explore the DNA domain organization of the breast cancer loss-ofheterozygosity
region on human chromosome 16q22.1, we have identified
a significant portion of the scaffold/matrix attachment regions (S/
MARs) within this region. Forty independent putative S/MAR elements
were assigned within the 16q22.1 locus. More than 90% of these S/
MARs are AT rich, with GC contents as low as 27% in 2 cases. Thirtynine
(98%) of the S/MARs are located within genes and 36 (90%) in
gene introns, of which 15 are in first introns of different genes. The
clear tendency of S/MARs from this region to be located within the
introns suggests their regulatory role. The genomic interval mapped
has been identified as a possible region harboring tumor suppressor
genes in both invasive ductal and invasive lobular breast carcinomas.
The E-cadherin gene, which is located within this region, has been
shown to be mutated in lobular breast carcinomas, resulting in loss of
E-cadherin expression. However, in most cases of ductal carcinoma,
E-cadherin is normally expressed, suggesting that other genes within
chromosome 16q22.1 may be involved in the development of this tumor
subtype. The construction of comprehensive S/MAR maps of the
region using a panel of breast cancer cell lines may provide information
on relevance for the etiology of breast carcinomas. Changes of
positions of regulatory elements such as S/MAR within the region may
allow an understanding of how the genes in the region are regulated
and how the structural architecture is related to the functional organization
of the DNA.
P0519. Expression of two testis-specific genes, TSGA10 and
SYCP3, in skin cancer
M. B. Mobasheri 1 , M. Aarabi 2 , I. Jahanzad 3 , M. H. Modarressi 1,2 ;
1 Department of Medical Genetics, Tehran University of Medical Sciences, Tehran,
Islamic Republic of Iran, 2 Reproductive Biotechnology Research Center,
Avesina Research Institute, Tehran, Islamic Republic of Iran, 3 Department of
Pathology, Tehran University of Medical Sciences, Tehran, Islamic Republic of
Iran.
Cancer-testis genes are a group of genes expressed in testicular germinal
cells and a range of human cancers. Testis specific gene A10
(TSGA10) is expressed in testis and actively dividing and fetal differentiating
tissues. SYCP3 gene is supposed to be a testis specific gene
and constitutes the core of the lateral elements of synaptonemal complex.
It has role in regulating DNA binding to the chromatid axis, sister
chromatid cohesion, synapsis, and recombination. Methods: In this
study expression of TSGA10 and SYCP3 were investigated in 26 skin
cancer using RT-PCR. Diagnosis of cancer was based on histopathological
reports. Results: TSGA10 expression was observed in 66.4%
of total of skin tumors including melanomas with 85.7%, Basal cell carcinomas
(BCC) with 75% and Squamous cell carcinomas (SCC) with
40% positive expression of TSGA10, but, SYCP3 transcripts were not
found in skin tumors. Conclusion: These results may get further insight
into the potential role as cancer marker and as cancer testis gene implicated
in tumorogenesis of skin tumors in the case of TSGA10
P0520. Evaluation of the relationship between XRCC1 and XPD
Polymorphisms and laryngeal squamous cell carcinoma (LSCC)
H. Acar 1 , Z. İnan 1 , K. Öztürk 2 ;
1 Dept. of Medical Genetics, Selcuk University, Meram Medical Faculty, Konya,
Turkey, 2 Dept. of Otolaryngology, Meram Medical Faculty, Selcuk Unıversıty,
Konya, Turkey.
Squamous cell carcinoma is the most common (90-95%) of all head
and neck cancers (SCCHN), and laryngeal squamous cell carcinoma
(LSCC) is one of the most common tumors of the upper aerodigestive
tract. The incidence varies according to geographical area and most
probably depends on specific environmental risk factors. Many studies
reported that polymorphisms in DNA repair genes reduce their capacity
to repair DNA damage and thereby lead to a greater susceptibility
to cancer. DNA repair enzymes continuously monitor DNA to correct
damaged nucleotide residues generated by exposure to environmen-
1 0
tal mutagenic and cytotoxic compounds or carcinogens. Our objective
was to investigate the association, if any, between XRCC1 (X-ray
repair cross-complementing 1) for Arg399Gln and XPD (ERCC2) for
Lys751Gln polymorphic genotypes and LSCC, smoking and alcohol
habits, tumor-node-metastasis (TNM) classification, and patient age.
There was no significant difference in the genotype distribution of XPD
between LSCC patients and their smoking and alcohol habits, tumornode-metastasis
(TNM) classification, and patient age and controls for
each polymorphism (p>0.05). There was a significant difference between
the genotype distributions of XRCC1 in patients and in control
groups (P