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1.
Physiol Res ; 68(Suppl 3): S287-S296, 2019 12 20.
Article in English | MEDLINE | ID: mdl-31928046

ABSTRACT

Burden of obesity is increasing in the contemporary world. Although multifactorial in origin, appropriate mitochondrial function of adipocytes emerges as a factor essential for healthy adipocyte differentiation and adipose tissue function. Our study aimed to evaluate mitochondrial functions of human adipose-derived mesenchymal stem cells committed to adipogenesis. On days 0, 4, 10, and 21 of adipogenesis, we have characterized adipocyte proliferation and viability, quantified lipid accumulation in maturing cells, performed qualitative and quantitative analysis of mitochondria, determined mitochondrial respiration of cells using high-resolution respirometry, and evaluated mitochondrial membrane potential. In the course of adipogenesis, mitochondrial oxygen consumption progressively increased in states ROUTINE and E (capacity of the electron transfer system). State LEAK remained constant during first days of adipogenesis and then increased probably reflecting uncoupling ability of maturing adipocytes. Citrate synthase activity and volume of mitochondrial networks increased during differentiation, particularly between days 10 and 21. In addition, lipid accumulation remained low until day 10 and then significantly increased. In conclusion, during first days of adipogenesis, increased mitochondrial respiration is needed for transition of differentiating cells from glycolytic to oxidative metabolism and clonal expansion of preadipocytes and then more energy is needed to acquire typical metabolic phenotype of mature adipocyte.


Subject(s)
Adipocytes/metabolism , Adipogenesis , Mesenchymal Stem Cells/physiology , Mitochondria/metabolism , Cell Respiration , Cells, Cultured , Female , Humans , Lipid Metabolism , Membrane Potential, Mitochondrial
2.
Physiol Res ; 67(Suppl 4): S577-S592, 2018 12 31.
Article in English | MEDLINE | ID: mdl-30607965

ABSTRACT

Ample experimental evidence suggests that sepsis could interfere with any mitochondrial function; however, the true role of mitochondrial dysfunction in the pathogenesis of sepsis-induced multiple organ dysfunction is still a matter of controversy. This review is primarily focused on mitochondrial oxygen consumption in various animal models of sepsis in relation to human disease and potential sources of variability in experimental results documenting decrease, increase or no change in mitochondrial respiration in various organs and species. To date, at least three possible explanations of sepsis-associated dysfunction of the mitochondrial respiratory system and consequently impaired energy production have been suggested: 1. Mitochondrial dysfunction is secondary to tissue hypoxia. 2. Mitochondria are challenged by various toxins or mediators of inflammation that impair oxygen utilization (cytopathic hypoxia). 3. Compromised mitochondrial respiration could be an active measure of survival strategy resembling stunning or hibernation. To reveal the true role of mitochondria in sepsis, sources of variability of experimental results based on animal species, models of sepsis, organs studied, or analytical approaches should be identified and minimized by the use of appropriate experimental models resembling human sepsis, wider use of larger animal species in preclinical studies, more detailed mapping of interspecies differences and organ-specific features of oxygen utilization in addition to use of complex and standardized protocols evaluating mitochondrial respiration.


Subject(s)
Mitochondria/metabolism , Multiple Organ Failure/metabolism , Oxygen Consumption/physiology , Sepsis/metabolism , Animals , Cell Hypoxia/physiology , Cell Respiration/physiology , Humans , Mitochondria/pathology , Multiple Organ Failure/pathology , Sepsis/pathology
3.
Physiol Res ; 67(Suppl 4): S633-S643, 2018 12 31.
Article in English | MEDLINE | ID: mdl-30607970

ABSTRACT

Hyperbaric oxygen (HBO) therapy, i.e. breathing pure oxygen under increased environmental pressures serves as a treatment for diverse medical conditions. However, elevated oxygen concentration can be detrimental to central nervous system or lungs. Our study aimed to evaluate the effects of repeated exposure to HBO on mitochondrial respiration assessed by high-resolution respirometry (HRR), cell viability estimated by PrestoBlue® reaction, morphology analyzed by routine phase contrast and fluorescent microscopy, and superoxide dismutase (SOD) and citrate synthase (CS) activities using human lung fibroblasts. The cells were exposed to HBO for 2 h per day for 5 consecutive days. One day after the last exposure, HBO cells displayed significantly smaller area and perimeter, compromised viability and elevated SOD activity. No changes were detected in CS activity or quality of mitochondrial network. HRR revealed impaired mitochondrial oxygen consumption manifested by increased leak respiration, decreased activity of complex II and compromised ATP-related oxygen consumption when fatty acids were oxidized. Our findings document that in conditions mimicking chronic intermittent exposure to HBO, lung fibroblasts suffer from compromised mitochondrial respiration linked to complex II and impaired cellular growth in spite of increased antioxidant defense. Underlying mechanism of this HBO-induced mitochondrial dysfunction should be further explored.


Subject(s)
Fibroblasts/metabolism , Hyperbaric Oxygenation/adverse effects , Lung/metabolism , Mitochondria/physiology , Oxygen Consumption/physiology , Cell Line , Cell Respiration/physiology , Cell Survival/physiology , Humans , Lung/cytology , Oxidative Stress/physiology
4.
Neoplasma ; 64(2): 278-282, 2017.
Article in English | MEDLINE | ID: mdl-28043156

ABSTRACT

Pheochromocytomas and Paragangliomas (PHEO/PARA) are rare endocrine tumors originating from the adrenal medulla. More than 20 genes are involved in the tumorigenesis of these tumors, but a substantial part of the causative genetic events remains unexplained. A recent study has reported the presence of the activating BRAF V600E mutation in PCC, suggesting a role for BRAF activation in tumor development. Other studies have not find this mutation. This study investigates the occurrence of the BRAF V600E mutation in these tumors.A cohort of 64 PHEO/PARA were screened for the BRAF V600E mutation using direct Sanger sequencing and QRT-PCR.All cases investigated displayed wild-type without V600E BRAF mutationTaken together with all previously screened tumors up to date, only 1 V600E BRAF mutation has been found among 427 PCCs. These findings imply that the V600E BRAF mutation is a rare event in PHEO/PARA.


Subject(s)
Adrenal Gland Neoplasms/genetics , Paraganglioma/genetics , Pheochromocytoma/genetics , Proto-Oncogene Proteins B-raf/genetics , Cohort Studies , Humans , Mutation
5.
Neoplasma ; 62(4): 509-20, 2015.
Article in English | MEDLINE | ID: mdl-25997972

ABSTRACT

Early diagnosis is a prerequisite of the more successful treatment of cancer. In gynaecological cancers, such as ovarian, endometrial and cervical cancers, the recent efforts are aimed at finding novel diagnostic biomarkers to help reduce the worldwide health burden associated with these cancers. In this review, we focus on the recent research progress in circulating, particularly cell-free microRNAs expression achieved in ovarian, endometrial and cervical cancers showing an opportunity to find novel diagnostic biomarkers for these malignant diseases. With the onset of microRNAs investigations showing their diagnostic potential in many diseases, their role in gynaecological cancers has been examined as well. However, similarly as in many other diseases, the vast majority of research on microRNAs expression has been dealing with tissue samples and cell lines. Recently, as the novel approaches focused on cell-free microRNAs expression have emerged, several studies identified their potential diagnostic and prognostic value in gynaecological cancers using blood, serum/plasma or urine samples. More research will be needed to establish circulating and extracellular microRNAs as the novel diagnostic markers for gynaecological malignancies. Inconsistency of results across the studies due to technical and biological variation, and a low number of this kind of investigations are the main potential pitfalls remaining to be resolved.

6.
Int J Lab Hematol ; 37(2): 231-7, 2015 Apr.
Article in English | MEDLINE | ID: mdl-24963875

ABSTRACT

INTRODUCTION: CD157 has been reported as a potentially useful marker for paroxysmal nocturnal hemoglobinuria (PNH) testing by flow cytometry (FCM). METHODS: We determined the performance characteristics of a CD157-based five-color assay and compared results from patient analysis with results obtained with a previously validated CD14/CD24-based six-color protocol. RESULTS: Coefficient of variation (CV) for intra-/interassay precision analysis of granulocytes ranged from 0.88/0.09% to 3.02/3.71% and from 0.20/0.08% to 8.83/4.04% for the five- and six-color protocol, respectively. For monocyte, CV ranged from 0.42/0.49% to 8.13/4.80% for the five-color protocol and from 0.28/0.70% to 5.41/3.19% for the six-color protocol within various PNH clones. Coefficient of determination (r(2) ) for linear regression analysis of PNH clones ranging from 0.3 to 99.8% was >0.99 in all cases, Wilcoxon ranks test showed no statistically significant differences (P > 0.05), and Bland-Altman analysis demonstrated agreement with mean bias ranging from -0.02 to 0.38. CONCLUSION: Our results confirm very good performance characteristics for both intra- and interassay precision analyses, excellent correlation, and agreement between approaches. In agreement with recently published data, our experience supports the clinical relevance of CD157 for a rapid and cost-effective simultaneous evaluation of PNH leukocytes by flow cytometry.


Subject(s)
ADP-ribosyl Cyclase/metabolism , Antigens, CD/metabolism , Flow Cytometry/methods , Granulocytes/metabolism , Hemoglobinuria, Paroxysmal/diagnosis , Hemoglobinuria, Paroxysmal/metabolism , Monocytes/metabolism , Biomarkers , Flow Cytometry/standards , GPI-Linked Proteins/metabolism , Humans , Immunophenotyping/methods , Immunophenotyping/standards , Leukocytes/metabolism , Reproducibility of Results
7.
Clin Lab ; 60(2): 217-24, 2014.
Article in English | MEDLINE | ID: mdl-24660533

ABSTRACT

BACKGROUND: Comparison between consensual approaches for the detection of paroxysmal nocturnal hemoglobinuria (PNH) clones by flow cytometry (FCM) following the international clinical cytometry society (ICCS) guidelines has not been widely reported. METHODS: We determined the performance characteristics of 4, 5, and 6-color protocols for white blood cell (WBC) and one and two-color protocols for red blood cell (RBC) evaluation for different PNH target clones and compared results from PNH patient analysis. RESULTS: Coefficient of variation (CV) for precision/reproducibility analysis ranged from 0.01%/0.12% to 2.56%/ 3.59% for granulocytes, from 0.07%/0.08% to 3.87%/11.61% for monocytes and from 0.4%/1.02% to 6.53%/ 5.1% for RBCs within different approaches and target PNH clones. Comparison of individual protocols revealed excellent correlation (r = 0.99), Wilcoxon rank tests found no statistically significant differences (p > 0.05), Bland-Altman analysis proved agreement for all PNH clones (mean bias ranging from 0.02 to 2.2). CONCLUSIONS: Our results confirm good intralaboratory characteristics for precision and reproducibility analysis, excellent correlation and agreement between approaches underlining the primary role of optimally selected glycophosphatidylinositol (GPI)-specific reagents and secondary role of number, type of gating reagents and gating strategy.


Subject(s)
Flow Cytometry/methods , Guidelines as Topic , Hemoglobinuria, Paroxysmal/pathology , Societies, Scientific , Clone Cells , Humans , Linear Models , Reproducibility of Results
8.
Ceska Gynekol ; 78(5): 432-42, 2013 Nov.
Article in Czech | MEDLINE | ID: mdl-24313429

ABSTRACT

The most common gynecological malignancy, the endometrial carcinoma, is mostly diagnosed at early stages. However, diagnosis at advanced stages is accompanied by the high mortality rate. It is suggested that this cancer is one of the less studied female cancers. The necessity to establish novel diagnostic markers has led to investigations of small non-coding RNAs, particularly microRNAs, also in endometrial cancer. There have been found many microRNAs potentially associated with carcinogenesis and clinico-pathological data including prognosis for patients. Many microRNAs may also serve as diagnostic markers for non-invasive diagnostics using blood plasma. We reviewed extensively the published research focused on microRNAs that have been found deregulated particularly in tissue samples within the both major types of endometrial cancer (type 1 and type 2). They are presented in the view of their potential targets and mechanisms of action. Some microRNAs have been found deregulated also in blood plasma. There exists a high level of inconsistency across the studies as many microRNAs have been found only within one or a few studies so far. However, there are some microRNAs consistently deregulated as suggested several investigations. There remains the urgent need of more intensive research focused on the microRNAs and their regulatory role in endometrial cancer. Such a research should provide the basis for the introducing novel diagnostic tools into the clinical practice.


Subject(s)
Endometrial Neoplasms , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , Molecular Diagnostic Techniques/methods , RNA, Neoplasm/genetics , Endometrial Neoplasms/diagnosis , Endometrial Neoplasms/genetics , Endometrial Neoplasms/metabolism , Female , Humans , Prognosis
9.
Folia Biol (Praha) ; 59(3): 110-5, 2013.
Article in English | MEDLINE | ID: mdl-23890478

ABSTRACT

α-Actinin 4, encoded by ACTN4, is an F-actin crosslinking protein which belongs to the spectrin gene superfamily. It has a head-to-tail homodimer structure with three main domains. Mutations in ACTN4 are associated with idiopathic nephrotic syndrome (NS). However, until today only a few mutations have been described in this gene. We used genomic DNA of 48 patients with focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) to screen for ACTN4 mutations by high-resolution melting analysis (HRM). Suspect samples were sequenced and compared with healthy controls. To investigate the prevalence and possible effect of some substitutions found in FSGS/MCD patients we also looked for these changes in patients with IgA nephropathy (IgAN) and membranous glomerulonephritis (MGN). We found 20 exonic and intronic substitutions in the group of 48 Czech patients. The substitution 2242A>G (p.Asn748Asp) is a candidate mutation which was identified in one patient but not in any of the 200 healthy controls. Exon 19 seems to be a variable region due to the amount of revealed polymorphisms. In this region we also found three unreported substitutions in IgAN patients, c.2351C>T (p.Ala784Val), c.2378G>A (p.Cys793Tyr) and c.2393G>A (p.Gly798Asp). These substitutions were not found in any tested healthy controls. To conclude, the ACTN4 mutations are not a frequent cause of FSGS/MCD in Czech adult patients. One new ACTN4 mutation has been identified.


Subject(s)
Actinin/genetics , Glomerulosclerosis, Focal Segmental/genetics , Adult , Amino Acid Sequence , Amino Acid Substitution , Consensus Sequence , Czech Republic , DNA Mutational Analysis , Exons/genetics , Female , Glomerulonephritis, IGA/epidemiology , Glomerulonephritis, IGA/genetics , Glomerulonephritis, Membranous/genetics , Glomerulosclerosis, Focal Segmental/epidemiology , Humans , Introns/genetics , Male , Middle Aged , Molecular Sequence Data , Mutation, Missense , Nephrosis, Lipoid/epidemiology , Nephrosis, Lipoid/genetics , Nucleic Acid Denaturation , Point Mutation , Sequence Alignment , Sequence Homology, Amino Acid
10.
Ceska Gynekol ; 78(2): 169-74, 2013 Apr.
Article in Czech | MEDLINE | ID: mdl-23710981

ABSTRACT

Ovarian cancer is the most malignant and the second most common gynecological cancer which encompasses a heterogeneous group of tumors with a different etiology. Extra-ovarian tissues may play a role in the development of ovarian cancer, despite this issue is still debated. This disease is associated with a strong chemoresistance and tendency to recurrence, and asymptomatic behaviour at early stages. Effective screening markers have not been established yet. Cancer stem cells have been postulated to play a role within tumor formation and by the establishment of chemotherapy-resistant population of malignant cells after the surgery and application of chemotherapy. These cells are multipotent cells capable of un-limited divisions and have potential to induce tumorigenesis in immune-suppressed mice. Their detailed characterization is still an open issue, however there have been identified several markers associated with ovarian cancer stem cells. The major markers of ovarian cancer stem cells identified so far are CD133, ALDH, CD44, CD117, CD24 and EpCAM. Their occurrence in primary tumors may be associated with patients´ prognosis; however there are insufficient data for definite conclusions. Dynamic processes of carcinogenesis result also in changes of cancer stem cells phenotypes based on the microenvironmental changes within the tumor. The markers may thus be acquired, or lost, as it has been proven experimentally. As regards the possibility to use targeted, specific therapy approaches, there are some promising studies, suggesting this may be a method of potential treatment. Further characterization and functional studies of cancer stem cells will be necessary for the elucidation of carcinogenesis, chemoresistance and metastases formation-associated processes. Such studies will be the basis for establishment of novel diagnostic, prognostic and therapeutic approaches for the ovarian cancer treatment. The most recent results on ovarian cancer stem cells research are presented in this paper.


Subject(s)
Neoplastic Stem Cells , Ovarian Neoplasms , Animals , Biomedical Research , Female , Humans , Mice , Prognosis
11.
Folia Biol (Praha) ; 58(4): 173-6, 2012.
Article in English | MEDLINE | ID: mdl-22980509

ABSTRACT

Blood filtration and formation of primary urine in the kidney glomerulus is provided by a specialized membrane called slit diaphragm located between well-branched pedicels of podocytes. Actually, the slit diaphragm is a protein supercomplex, whose disruption can cause failure of renal filtration, and patients usually manifest nephrotic syndrome. Recently, familial forms of nephrotic syndrome have been described which arise from malfunction of mutated proteins making up the slit diaphragm. In 2005 it was found that one of the proteins present in this complex was non-selective cation channel TRPC6. The aim of this work was to screen mutations and polymorphisms of the TRPC6 gene in a group of 64 Czech patients with nephrotic syndrome and subsequently, on the basis of these data, evaluate the role of mutations in the TRPC6 gene in Czech population. The analysis was performed by the PCR method followed by direct sequencing and high-resolution melting method. We have not identified any mutations in our group of patients. Two additional single nucleotide polymorphisms - p.P15S and p.A404V - were detected along with nucleotide changes that did not result in amino acid changes and with a few intronic changes. P.P15S heterozygotes were more frequent in patients with steroid-resistant FSGS than in steroid- sensitive patients (29 % versus 12.1 %). To conclude, we did not find any probable disease-causing mutation in the TRPC6 gene in the cohort of 64 Czech patients. The p.P15S polymorphism might have some influence on the therapeutic response of FSGS patients.


Subject(s)
DNA Mutational Analysis , Glomerulosclerosis, Focal Segmental/genetics , Nephrosis, Lipoid/genetics , Polymorphism, Genetic , TRPC Cation Channels/genetics , Adult , Czech Republic , Female , Humans , Male , Middle Aged , Mutation , Polymerase Chain Reaction , TRPC6 Cation Channel , Young Adult
12.
Klin Onkol ; 25 Suppl: S21-6, 2012.
Article in Czech | MEDLINE | ID: mdl-22920202

ABSTRACT

Pheochromocytomas and paragangliomas are tumors arising from chromaffin cells. These tumors produce catecholamines and are typically found with symptoms and signs that may include hypertension (persistent or episodic), palpitations, headache and sweating. So far, 10 different genes have been associated with both tumors and other genes are expected to be detected. Pheochromocytoma and paraganglioma can occur as a part of genetic syndromes - familial paragangliomas (SDH genes, SDHAF2 gene), von Hippel-Lindau syndrome (VHL gene), multiple endocrine neoplasia type 2 (RET gene), and neurofibromatosis type 1 (NF1 gene). These tumors may be the first and only manifestation of these genetic syndromes. Patients with SDHB mutations are at high risk to develop malignant disease and unfortunately current therapeutic options for malignant form of disease are poor. Genetic testing plays a key role in the management of these tumors and therefore not only index patients with pheochromocytoma but also relatives should be tested. Management of this disease requires multidisciplinary cooperation and should be performed in the specialized medical centres.


Subject(s)
Neoplastic Syndromes, Hereditary/genetics , Paraganglioma/genetics , Pheochromocytoma/genetics , Genetic Testing , Heterozygote , Humans , Neoplastic Syndromes, Hereditary/diagnosis , Paraganglioma/diagnosis , Pheochromocytoma/diagnosis
13.
Neoplasma ; 58(6): 457-68, 2011.
Article in English | MEDLINE | ID: mdl-21895398

ABSTRACT

Ovarian cancer representing the most lethal gynecologic malignancy escapes from the efforts to manage the disease. We reviewed the current state of the research considering three main concepts on origin of ovarian cancer including epithelial-mesenchymal transition, secondary origin from Müllerian system and cancer stem cell hypothesis. Cytogenetic and molecular characteristics of ovarian cancer are focused particularly on microRNA expression studies revealing huge potential in recent years, although other transcriptomic, proteomic, epigenetic, epidemiologic and immunological factors are touched upon, too. Routine and investigated diagnostic and treatment methods are outlined and several factors revealed to be associated with prognosis of the disease. Despite the huge progress on elucidating factors involved in ovarian cancer carcinogenesis, still remains urgent need to improve both the diagnostics as well as the treatment.


Subject(s)
Cell Transformation, Neoplastic , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/therapy , Female , Humans , Prognosis
14.
Ceska Gynekol ; 76(3): 230-4, 2011 Jun.
Article in Czech | MEDLINE | ID: mdl-21838155

ABSTRACT

AIM OF STUDY: Analysis of incidence of chromosomal abnormalities and variants in foetuses karyotyped because of the advanced maternal age. TYPE OF STUDY: A retrospective epidemiological study of results of cytogenetic examinations followed amniocentesis in 418 foetuses. MATERIAL AND METHODS: In our study we have used data from archives of the Cytogenetic laboratory of the Institute of Biology and Medical Genetics of the First Faculty of Medicine, Charles University and General Teaching Hospital in Prague. We have included only the cases where the amniocentesis was performed solely because of advanced maternal age. All cases were divided in specific groups and analyzed. RESULTS: There were totally 1107 karyotype examinations following the amniocentesis between 2007 and 2009 in our laboratory. Among these cases, 418 amniocenteses (37.8%) were performed only because of the advanced maternal age. The mean maternal age in this group was 38.02 +/- 2.4 years. In the whole group of 418 foetuses, 256 of them (61.24%) had normal karyotype, without chromosomal variants or pathologies. In 9 cases (2.15%) we identified pathologic karyotype. Down syndrome was identified in 3 cases (0.72%), what means one case of Down syndrome per 139 amniocenteses performed because of the advanced maternal age. Among other pathologies there were three (0.72%) gonosomal aneuploidies. Variants of acrocentric chromosomes were identified in 121 (28.95%) foetuses, variants of heterochromatine regions in 53 (12.68%) foetuses and other karyotype variants in one case (0.24%). In some cases, we have identified coincidence of more than one chromosomal variant and/or pathology. CONCLUSION: Our study presents the overview of chromosomal pathologies and variants that can be identified in fetal karyotype examinations because of the advanced maternal age. The efficiency of Down syndrome identification did not differ from the overall efficiency of amniocentesis in the Czech Republic. Advanced maternal age is still considered as an important part of the indication criteria for invasive prenatal diagnosis.


Subject(s)
Amniocentesis , Chromosome Disorders/diagnosis , Karyotyping , Maternal Age , Prenatal Diagnosis , Adult , Female , Humans , Pregnancy
16.
Eur J Cancer ; 43(10): 1617-21, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17524638

ABSTRACT

Some of the APC negative FAP and AFAP cases have recently been found to be attributable to MYH associated polyposis (MAP). MAP is an autosomal recessive syndrome associated with 5-100 colorectal adenomas and caused by mutation in the MYH gene. Here, we screened for germline MYH mutations in 82 APC-mutation-negative probands with classical and attenuated familial adenomatous polyposis using the denaturing high performance liquid chromatography (DHPLC) method in combination with sequencing. Altogether 12 previously reported changes and four novel genetic alterations, mostly in intronic sequences, were identified. The results revealed the presence of biallelic germline MYH mutations in two patients. These patients were compound heterozygotes for two of the most common germline mutations c.494 A>G (p.Y165C); c.1,145 G>A (p.G382D). These variants are established to be associated with adenomatous polyposis and colorectal cancer. No novel pathogenic mutation has been identified in our study.


Subject(s)
Adenomatous Polyposis Coli/genetics , Genes, APC , Germ-Line Mutation/genetics , Myosin Heavy Chains/genetics , Czech Republic , DNA Mutational Analysis , DNA, Neoplasm/genetics , Exons/genetics , Humans
17.
Cas Lek Cesk ; 145(6): 475-9, 2006.
Article in Czech | MEDLINE | ID: mdl-16836001

ABSTRACT

BACKGROUND: Hereditary colorectal adenomatous polyposis syndromes are a predisposition to colorectal carcinoma development. The familial adenomatous polyposis is the most common analyzed syndrome that results from germline mutations in the APC gene. In addition to, the autosomal recessive form of polyposis has been recently reported. This disease is caused by germ-line mutations in the base excision repair MYH gene. The goal of this study is the identification of genetic causes of the colorectal polyposis, the determination of the frequency and type of the APC and MYH germ-line mutations in the set of families with colorectal polyposis in Czech population. METHODS AND RESULTS: The set of 103 probands with FAP was screened for germ-line APC mutations using the Protein Truncation Test and Denaturing Gradient Gel Electrophoresis. The MYH mutational screening was performed on 60 unrelated patients without detected APC mutations using the Denaturing High Performance Liquid Chromatography. Automated sequencing was carried out to identify found mutations. Totally, the 51 germ-line APC mutations (69,9%) are reported in the set of 72 probands including 31 novel mutations unique for Czech population. Molecular genetic analysis of the MYH gene revealed 15 DNA variations (25 %) including two patients identified as p.Y 165C/p.G382D compound heterozygotes (3,3%) and 13 polymorphisms or intronic changes (21,7%). The novel variants were detected in the 5 patients. CONCLUSION: Present study reflects the extremely heterogenous spectrum of the APC mutations in Czech population and confirms the previously reported data. However, the changes found in the MYH gene still need more extensive studies. Our results are important for genetic counselling and further clinical management among at-risk family members. It also enables distinction among different types of the colorectal polyposis.


Subject(s)
Adenomatous Polyposis Coli/genetics , DNA Glycosylases/genetics , Genes, APC , Germ-Line Mutation , Mutation , Humans , Pedigree
18.
Cas Lek Cesk ; 145(3): 201-3, 2006.
Article in Czech | MEDLINE | ID: mdl-16634478

ABSTRACT

BACKGROUND: Mutations 657del5 and R215W in exon 6 of tumor suppressor gene NBS I are found in 1% Slavic populations. Increased occurrence of cancer was repeatedly reported in adult relatives of patients with Nijmegen breakage syndrome. Among children with oncological problematic, nonsignificantly increased frequency of NBS1 heterozygotes was found, which seems not to play any important role in cancerogenesis in childhood. However, the proportion of NBS heterozygotes among adult patients with malignancies could be significant and their therapy and follow up should respect their hyperradiosensitivity. METHODS AND RESULTS: Mutations in exon were studied in 706 adult patients with malignancies. We found 5 NBS heterozygotes, which not more than the population prevalence (1:129-165). Increased frequency of NBS heterozygotes was found among patients with colon and rectal cancer (2/101), breast cancer (1/60), skin malignancies (1/98). CONCLUSIONS: Surprisingly only one NBS heterozygote was found among 228 patients with nonHodgkin lymphoma, the malignancy which is a common complication in NBS homozygotes. Other types of malignancies were uncommon and only one R215W heterozygote was found. Comparison frequency of NBS heterozygotes with incidence NBS among person older than 70 years shows significant difference. Prevention of malignancies by avoidance from ionisation could be realized also in relatives of patients after identification of their genotype.


Subject(s)
Cell Cycle Proteins/genetics , Genes, Tumor Suppressor , Mutation , Neoplasms/genetics , Nuclear Proteins/genetics , Adult , Female , Heterozygote , Humans , Male
19.
Ren Fail ; 26(2): 119-25, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15287194

ABSTRACT

BACKGROUND: A significant phenotypical variability is observed in autosomal dominant polycystic kidney disease (ADPKD). The variability cannot be fully explained by the genetic heterogeneity of the disease. We examined the influence of G-protein beta3-subunit C825T polymorphism and endothelial nitric oxide synthase Glu298Asp polymorphism on the progression of ADPKD towards end stage renal failure (ESRF). METHODS: 306 ADPKD patients (pts) were analyzed; 261 pts (136 males, 125 females) with ESRF, with subgroup of 73 pts (44 males, 29 females) with ESRF before 45 years (rapid progressors), 46 pts (20 males, 26 females) with ESRF later than in 63 years (slow progressors) and 45 ADPKD pts (17 males, 28 females) in mean age 51 years with serum creatinine under 110 micromol/L (slow progressors) and 100 genetically unrelated healthy Czech subjects. DNA samples from collected blood were genotyped for G-protein beta3-subunit C825T genotype in exon 10 and for endothelial nitric oxide synthase Glu298Asp genotype in exon 7. RESULTS: The G-protein beta3-subunit C825T genotype exhibited no significant differences among the groups of slow progressors (6.6% (6/91) TT, 54.9% (50/91) CT, 38.8% (35/91) CC), rapid progressors (9.6% (7/73) TT, 46.6% (34/73) CT, 43.8% (32/73) CC), ADPKD group with ESRF between 40-63 years (9.2% (13/142) TT, 50% (71/142) CT, 40.8% (58/142) CC) and control group (12% TT, 44% CT, 44% CC). When comparing the ages of ESRF of all patients with ESRF, we did not find significant differences in the ages: males TT--51.7+/-8.8 years, CT--51.9+/-10.3 years, CC--49.7+/-10.2 years and females TT--56+/-9.9 years, CT--53.2+/-8.5 years, CC--53.9+/-8.7 years. The endothelial nitric oxide synthase Glu298Asp and Asp29Asp genotypes were significantly more frequent in rapid progressors (9.6% (7/73) Asp/Asp, 39.7% (29/73) Asp/Glu, 50.7% (37/73) Glu/Glu) and in ADPKD group with ESRF between 40-63 years (11.3% (16/142) Asp/Asp, 41.5% (59/142) Asp/Glu, 47.2% (67/142) Glu/Glu) in comparison with slow progressors (8.8% (8/91) Asp/Asp, 24.2% (22/91) Asp/Glu, 67.0% (61/91) Glu/Glu) and with control group (8% Asp/Asp, 32% Asp/Glu, 60% Glu/Glu) (Chi-square test, p<0.05). Comparing the ages of ESRF of all patients with ESRF, we did not find significant differences in the ages in males with Asp/Asp--54.9+/-10.4 years, Asp/Glu--50.2+/-9.4 years, Glu/Glu--51.0+/-10.4 years. We found out in homozygous Asp/Asp females significantly earlier onset of ESRF (49.2+/-5.6 years) in comparison with heterozygous females (53.3+/-7.2 years) and with Glu/Glu homozygous females (54.8+/-9.7 years) (t-test, p<0.05). CONCLUSION: We excluded the significance of G-protein beta3-subunit C825T polymorphism on the progression of ADPKD. We established the negative prognostic value of the carriers of Asp variant of eNOS polymorphism. Finding of new modifiers could have in future clinical consequences for ADPKD patients.


Subject(s)
Heterotrimeric GTP-Binding Proteins/genetics , Kidney Failure, Chronic/genetics , Nitric Oxide Synthase/genetics , Polycystic Kidney, Autosomal Dominant/genetics , Polycystic Kidney, Autosomal Dominant/physiopathology , Polymorphism, Genetic , Adult , Base Sequence , Czech Republic , Disease Progression , Exons/genetics , Female , Genetic Markers , Genotype , Humans , Kidney Failure, Chronic/physiopathology , Male , Middle Aged , Molecular Sequence Data , Nitric Oxide Synthase Type III , Polymerase Chain Reaction , Prognosis , Risk Assessment , Sensitivity and Specificity
20.
Hum Mutat ; 23(4): 397, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15024739

ABSTRACT

Familial adenomatous polyposis (FAP) is an autosomal dominant predisposition to colorectal cancer and is caused by germline mutations in the adenomatous polyposis coli gene. The most prominent clinical manifestation is the presence of hundreds to thousands of colorectal polyps. A milder phenotype is found in patients affected with AFAP/ multiple adenomas. We screened the entire APC coding region using the combination of DGGE, PTT and direct sequencing and identified causative mutations in 52 of 77 patients. Thirteen of the mutations found were novel. In addition, we also tested 21 APC mutation/negative probands for the two most common mutations in the MYH gene. Four patients showed neither dominant transmission of the disease nor evidence of APC mutations. In one of them the most common biallelic germline mutation in the MYH gene was detected. Correlations between the localization of germline mutations and clinical manifestations of the diseases are discussed.


Subject(s)
Adenomatous Polyposis Coli/genetics , Colorectal Neoplasms/genetics , DNA Glycosylases/genetics , Genes, APC , Germ-Line Mutation , Adenoma/genetics , Adenomatous Polyposis Coli/diagnosis , Colorectal Neoplasms/diagnosis , Czech Republic , DNA Mutational Analysis , Genotype , Phenotype
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