The
,
, and
genes encode for the nuclear MRN protein complex, which senses the DNA double strand breaks and initiates the DNA repair. The MRN complex also participates in the activation of ATM ...kinase, which coordinates DNA repair with the p53-dependent cell cycle checkpoint arrest. Carriers of homozygous germline pathogenic variants in the MRN complex genes or compound heterozygotes develop phenotypically distinct rare autosomal recessive syndromes characterized by chromosomal instability and neurological symptoms. Heterozygous germline alterations in the MRN complex genes have been associated with a poorly-specified predisposition to various cancer types. Somatic alterations in the MRN complex genes may represent valuable predictive and prognostic biomarkers in cancer patients. MRN complex genes have been targeted in several next-generation sequencing panels for cancer and neurological disorders, but interpretation of the identified alterations is challenging due to the complexity of MRN complex function in the DNA damage response. In this review, we outline the structural characteristics of the MRE11, RAD50 and NBN proteins, the assembly and functions of the MRN complex from the perspective of clinical interpretation of germline and somatic alterations in the
,
and
genes.
Ovarian cancer (OC) is the deadliest gynecologic malignancy with a substantial proportion of hereditary cases and a frequent association with breast cancer (BC). Genetic testing facilitates treatment ...and preventive strategies reducing OC mortality in mutation carriers. However, the prevalence of germline mutations varies among populations and many rarely mutated OC predisposition genes remain to be identified. We aimed to analyze 219 genes in 1333 Czech OC patients and 2278 population-matched controls using next-generation sequencing. We revealed germline mutations in 18 OC/BC predisposition genes in 32.0% of patients and in 2.5% of controls. Mutations in
,
,
, and mismatch repair genes conferred high OC risk (OR > 5). Mutations in
and
were associated with moderate risk (both OR = 3.5).
mutations dominated in almost all clinicopathological subgroups including sporadic borderline tumors of ovary (BTO). Analysis of remaining 201 genes revealed somatic mosaics in
and germline mutations in
and
associating with a high/moderate OC risk significantly; however, further studies are warranted to delineate their contribution to OC development in other populations. Our findings demonstrate the high proportion of patients with hereditary OC in Slavic population justifying genetic testing in all patients with OC, including BTO.
Cutaneous melanoma is the deadliest skin malignity with a rising prevalence worldwide. Patients carrying germline mutations in melanoma-susceptibility genes face an increased risk of melanoma and ...other cancers. To assess the spectrum of germline variants, we analyzed 264 Czech melanoma patients indicated for testing due to early melanoma (at <25 years) or the presence of multiple primary melanoma/melanoma and other cancer in their personal and/or family history. All patients were analyzed by panel next-generation sequencing targeting 217 genes in four groups: high-to-moderate melanoma risk genes, low melanoma risk genes, cancer syndrome genes, and other genes with an uncertain melanoma risk. Population frequencies were assessed in 1479 population-matched controls. Selected POT1 and CHEK2 variants were characterized by functional assays. Mutations in clinically relevant genes were significantly more frequent in melanoma patients than in controls (31/264; 11.7% vs. 58/1479; 3.9%; p = 2.0 × 10−6). A total of 9 patients (3.4%) carried mutations in high-to-moderate melanoma risk genes (CDKN2A, POT1, ACD) and 22 (8.3%) patients in other cancer syndrome genes (NBN, BRCA1/2, CHEK2, ATM, WRN, RB1). Mutations in high-to-moderate melanoma risk genes (OR = 52.2; 95%CI 6.6–413.1; p = 3.2 × 10−7) and in other cancer syndrome genes (OR = 2.3; 95%CI 1.4–3.8; p = 0.003) were significantly associated with melanoma risk. We found an increased potential to carry these mutations (OR = 2.9; 95%CI 1.2–6.8) in patients with double primary melanoma, melanoma and other primary cancer, but not in patients with early age at onset. The analysis revealed affected genes in Czech melanoma patients and identified individuals who may benefit from genetic testing and future surveillance management of mutation carriers.
The MRE11, RAD50, and NBN genes encode for the nuclear MRN protein complex, which senses the DNA double strand breaks and initiates the DNA repair. The MRN complex also participates in the activation ...of ATM kinase, which coordinates DNA repair with the p53-dependent cell cycle checkpoint arrest. Carriers of homozygous germline pathogenic variants in the MRN complex genes or compound heterozygotes develop phenotypically distinct rare autosomal recessive syndromes characterized by chromosomal instability and neurological symptoms. Heterozygous germline alterations in the MRN complex genes have been associated with a poorly-specified predisposition to various cancer types. Somatic alterations in the MRN complex genes may represent valuable predictive and prognostic biomarkers in cancer patients. MRN complex genes have been targeted in several next-generation sequencing panels for cancer and neurological disorders, but interpretation of the identified alterations is challenging due to the complexity of MRN complex function in the DNA damage response. In this review, we outline the structural characteristics of the MRE11, RAD50 and NBN proteins, the assembly and functions of the MRN complex from the perspective of clinical interpretation of germline and somatic alterations in the MRE11, RAD50 and NBN genes.
Idiopathic thrombocytopenic purpura (ITP) is a common clinical disorder of immune regulation leading to phagocytic destruction of platelets. Intravenous immunoglobulin (IGIV) has been used ...successfully to increase platelet count in patients with ITP. Baxter has developed a new IGIV (IGIV,10%), a 10% liquid immunoglobulin preparation with 3 dedicated virus reduction steps integrated into the manufacturing process. The efficacy and safety of this product was assessed in a prospective multi-center study in adult chronic ITP patients with platelet counts of 20x109/L or less. A total of 23 subjects were enrolled and treated for 2 to 5 days with a total dose of 2 g/kg. Of 21 subjects included in the per-protocol analysis data set, 15 responded to treatment (71.4%), achieving a platelet count of at least 50x109/L by Day 8. Fourteen of 15 responders reached this level by Day 5. The median duration of platelet response was 25 days and the highest median platelet count in the responders was 182x109/L. A total of 81 infusions were administered to the 23 subjects in the safety analysis data set. Among the 40 non-serious adverse events related to the use of the study drug, 35 were mild, 3 were moderate, and 2 were severe. The most frequent related adverse events were headache and pyrexia. The results of this study demonstrate that IGIV, 10% TVR Solution is effective in the treatment of adult subjects with chronic ITP and has an excellent safety profile.
Od roku 2005 jsou v registru pacientů léčených Thromboreductinem? (anagrelidem) v rámci některých center ČR vedeny údaje o nemocných léčených tímto preparátem od roku 2004. Cílem registru je ...podchycení léčebných odpovědí při terapii Thromboreductinem ? a nežádoucích účinků léku u pacientů s esenciální trombocytemií a dalšími myeloproliferacemi a následná analýza těchto dat. Dalším cílem je možnost podchycení dispozic ke vzniku klinické symptomatologie a komplikací onemocnění. Vedle samotného počtu trombocytů jsou sledovány i další rizikové faktory. V současné době jsou v databázi údaje o 336 nemocných. První analýzy údajů z registru ukazují na to, že anagrelid je velmi efektivní tromboredutivní látka, jejíž podávání je spojeno s poměrně nízkým výskytem nežádoucích účinků (11,8 %), které jsou nezávažné a obvykle tranzitorní. Poměrně pomalu je dosahováno terapeutického cíle (podle rizikové stratifikace pod 400, respektive pod 600 × 109/l trombocytů), což je patrně dáno málo razantními korekcemi dávek.
M. Penka, J. Schwarz, T. Pavlík, R. Pytlík, M. Doubek, P. Dulíček, D. Pospíšilová, J. Kissová, A. Hluší, M. Schützová, O. Černá, Y. Brychtová, T. Szotkowski, Z. Volková, J. Seghetová et al
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The production of two-wheeled rolling stock represents, at first glance, a simple assembly process that significantly affects the overall functionality and safety of the vehicle. This is due to ...residual stresses that arise after assembly by pressing the wheel on the axle. The state of stress after assembly remains in the design has a decisive influence on the load-bearing capacity of the two-wheel drive, its lifespan but also the transfer of the pulling force in the case of locomotives. Therefore, it is very important to find suitable methods for determining residual stresses. Numerical and experimental approaches are already in place to gain information on the state of stress after compression, or during a real operation. The developed techniques and tools for estimation of residual stresses in locomotive wheel treads based on the acoustoelasticity effect using electromagnetic acoustic transformation are described in the paper. The original results of residual stress measurement in the treads during a technological cycle of locomotive wheel pair manufacturing are presented.
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