2009 Vienna - European Society of Human Genetics

Cancer genetics
P06.203
molecular characterization of turkish patients with familial
hemophagocytic lymphohistiocytosis
G. Balta, H. Okur, N. Akarsu, S. Unal, A. Gurgey;
Hacettepe University, Ankara, Turkey.
The aim of this study was to elucidate molecular basis of familial hemophagocytic
lymphohistiocytosis (HLH) which has become an important
health problem in Turkey. Possibly familial HLH 143 Turkish patients
with either family history, consanguinity and/or relapses were studied
for 3 genes and chromosomal locus 9q21.3-q22 described to date.
Haplotype analysis for Perforin gene revealed homozygosity in 36
families. Sequencing showed homozygous 5 different mutations in 15
of the families. W374X detected in 9 of the families was first common
mutation in Turkish population. The mutations G149S was detected in
2, A91V in 2, V50M in 1, novel A593D in 1 patient and an asemptomatic
sibling who developed the disease afterwards. In Munc13-4 gene,
homozygosity/consanguineous common alleles were detected in 29
families. Sequencing of the gene revealed 6 different mutations in 11 of
the families. R214X, identified in 7 patients from 6 of the families, was
second common mutation. Homozygous R1065X, 627delT, L1044R,
novel 2135-2137delTCG and R414C were observed in the rest 5 families.
In Syntaxin 11 gene, homozygosity/consanguineous common allele
were shown in 26 families. Third common homozygous mutation,
c369-370delAG/c374-376delCGC, was identified in 7 unrelated families
from distant cities. Haplotype analysis revealed that this mutation
emerged from a common ancestor (founder effect). First prenatal diagnosis
was given in the gene. In addition, a novel homozgous E206K
mutation was identified in 2 patients of another family. No homozygosity
was detected for the chromosome 9 genomic locus. This study was
supported by TUBITAK (Project No: 105S396-SBAG 3193).
P06.204
Primary myelodisplastic syndromes (mDs)- prognostic impact of
additional chromosomal aberrations to 5q-
C. Ionita1 , D. Calamar1 , I. Ionita1 , D. Oros1 , M. Delamarian2 , H. Ionita1 ;
1 2 University of Medicine and Pharmacy, Timisoara, Romania, City Clinical Hospital,
Timisoara, Romania.
Background: Deletion of the long arm of chromosome 5 is the most
frequent chromosomal abnormality in MDS (10-15% of MDS cases).
Patients with del 5q, particularly those with the “5q-syndrome” have a
much better prognosis than other MDS subtypes. Presence of abnormalities
additional to del 5q has been suggested to negatively influence
this favorable outcome. Aim:To analyse the prognostic value of
cytogenetics aberrations additional to del (q5) in a cohort of patients
with MDS. Methods: We studied 124 MDS patients diagnosed and
treated in the Hematology Department of Timisoara between January
2001 - January 2007. Diagnosis was made according to FAB Group
criteria. FAB subtypes were: 52,1% RA, 12,6% RARS, 17,65% RABE,
13,45% RABET+, 4,2% CMML.Cytogenetic analysis showed 27 patients
with del (q5). From those, 12 had del (q5) associated with 1 additional
anomaly, 3 patients had 2 anomalies, 4 patients had 3 anomalies
and 5 patients had 4 anomalies. Additional anomalies observed in
those patients were: 7 monosomy, 7q, 8, 11 and 13 trisomy. Medium
survival in this group was 41 month, survival of the patients with isolated
5q deletion and only one additional anomaly was 62 month and
for the patients with 2, 3 and 4 anomalies was 50, 30 and respectively
8 month. Conclusion: Patients with 5q deletion in association with 2
or more additional chromosomal anomalies have negative prognostic
in global survival compared to those with only one or no aadditional
anomaly to 5q deletion.
P06.205
KRAs gene mutation testing - an inter-laboratory validated
workflow for quality - assured, clinical-grade results using
capillary electrophoresis
R. Petraroli 1 , A. Ballestrero 2 , A. Garuti 2 , I. Rocco 2 , V. Ludovini 3 , L. Pistola 3 , F.
Bianconi 3,4 , C. Davidson 5 , A. Felton 5 ;
1 Applied Biosystems Europe, Rome, Italy, 2 Dipartimento di Medicina Interna-
Università degli Studi di Genova, Genova, Italy, 3 Department of Medical Oncology
, Santa Maria Della Misericordia Hospital, Perugia, Italy, 4 Department of
electronic and information Engineering Perugia University, Perugia, Italy, 5 Ap-
plied Biosystems, Foster City, CA, United States.
In recent years, the research and clinical management of cancer have
changed and been revised on the basis of genetic features that characterize
the specific malignant neoplasm. The KRAS gene is an oncogene
that has established to play a fundamental role in the colonrectal
cancer therapy. It has been widely attested that novel therapeutic
agents, based on monoclonal antibody targeting the epidermal growth
factor receptor (EGFR), are effective only in a subset of patients. Activating
mutations in the KRAS gene are found in 30-40% of colorectal
tumours and are associated with poor response to anti-EGFR therapies.
Thus, the KRAS mutation status can predict which patient may
or may not benefit from anti-EGFR therapy. For this reason in 2007
the European Medicines Agency granted a conditional marketing authorization
for EGFR therapeutic agents intended for the treatment
of metastatic colon carcinoma with non-mutated KRAS (Doc.Ref.
EMEA/405113/2007). This decision led to the requirement of a KRAS
mutation test in the clinical practice and underlined the need for an
easy-to-operate test that generates quality-assured, clinical-grade results.
In this work we describe an inter-laboratory validation involving
two laboratories and Applied Biosystems for a KRAS gene sequencing
protocol. We developed an improved workflow from DNA to data analysis
on the latest generation of capillary electrophoresis instruments
with highest level of data quality and accuracy. The protocol has been
performed on 50 paraffin embedded colon rectal cancer samples.
P06.206
KRAs mutations in human endometrium. A report on 106 cases.
D. V. Konstantinova 1,2 , R. P. Kaneva 1,2 , A. Mitkova 1,2 , S. Bichev 3 , R. Dimitrov 4 ,
S. Ivanov 5 , E. Tiufektchieva 4 , I. Kremensky 1,3 , V. Mitev 6 ;
1 Molecular Medicine Center, Sofia, Bulgaria, 2 Department of Chemistry and
Biochemistry, Medical University-Sofia, Bulgaria, 3 National Genetics Laboratory,
Sofia, Bulgaria, 4 Clinic of Operative Gynecology, University Hospital of Obstetrics
and Gynecology “Maichin Dom”, Sofia, Bulgaria, 5 Clinic of Oncogynecology,
National Centre of Oncology, Sofia, Bulgaria, 6 Department of Chemistry
and Biochemistry, Medical University-Sofia, Sofia, Bulgaria.
Endometrial cancer (EC) is one of the most common gynecologic malignancies
in the industrialized world. The majority of cases fall in the
subgroup having a favorable prognosis, the type I EC. Activating somatic
mutations in the KRAS gene are common in both type I EC and
it’s precursor lesion - the endometrial hyperplasia (EH). However, their
relation to patient clinicopathological characteristics have remained
largely unclear.
We have sequenced exon 1 (containing codons 12 and 13) of the
KRAS gene in 101 EC and 5 EH samples.
The mutational frequency was 16 / 101 (15.8 %) in EC cases and 2
/ 5 (40 %) in EH cases. None of eight nonendometrioid EC samples
contained a mutation and have not been included in the following comparisons.
In EC, KRAS mutation was assocaited with grade one (6 /
18; 33.3 %; p = 0.04) and was more frequent in patients staged I/II (15
/ 82; 18.3 %) and in tumors that had not infiltrated the myometrium (3 /
12; 25 %) compared to patients staged III/IV (1 / 11; 9.1 %) and tumors
that had invaded the myometrium (13 / 81; 16 %).
We conclude that KRAS mutations arise very early in the pathogenesis
of EC and that they may contribute to the development of a large
proportion of low grade, low stage endometrioid endometrial cancer.
As the diagnosis of EH is complicated and has often been upstaged to
high-grade EC following hysterectomy, the implications of KRAS mutational
analysis should be considered.
P06.207
sensitive detection of KRAs mutations using mutant-enriched
PcR and reverse-hybridization teststrips
G. Kriegshaeuser 1 , B. Holzer 2 , B. Rauscher 1 , E. Schuster 2 , F. Kury 1 , R. Zeillinger
1,2 , C. Oberkanins 1 ;
1 ViennaLab Diagnostics GmbH, Vienna, Austria, 2 Molecular Oncology Group,
Department of Obstetrics and Gynaecology, Medical University of Vienna, Vienna,
Austria.
The KRAS gene encodes a GTPase, which plays a vital role in cellular
signaling processes. Mutated forms of the gene are potent oncogenes
and found in many human cancers. KRAS mutations are also predictive
for the response to cancer therapy with certain anti-EGFR monoclonal
antibodies and tyrosine kinase inhibitors.
We have developed a reverse-hybridization StripAssay targeting 10