Jan Mužík

Polymorphisms in the RAGE gene influence susceptibility to diabetes-associated microvascular dermatoses in NIDDM

To examine genetic polymorphism in the complete sequence of the Receptor of Advanced Glycation End products (RAGE) gene and its possible associations with diabetes-associated microvascular dermatoses (DAMD). Further, to analyze the distribution of individual genotype combinations on the particular polymorphic loci in the RAGE gene. A part of the RAGE gene spanning a region from -4 to 3334 bp was analyzed on a set of 45 subjects with non-insulin dependent diabetes mellitus (NIDDM) and parallel DAMD by means of PCR with subsequent heteroduplex and single-strand conformation polymorphism (SSCP) analyses. Allele frequencies and genotype combinations of novel common polymorphisms were determined in an associations study comprising four groups of subjects (n=390). Fourteen novel polymorphisms (R77C, V89V, 718G/T, 1704G/T, 1727A1728ins, H305Q, S307C, 2117A/G, 2184A/G, 2245G/A, 2249A/G, 2741G/A, and 3089ACdel) and one described previously (G82S) were identified. Significant association with microvascular dermatoses (MD) irrespective of NIDDM were found for exon mutation 82S (P= .004, after a correction for the number of comparisons P(corr) < .05) and marginally significant for intron variant 1704T (P= .032, P(corr)> .05). Calculated odds ratios for 82S and 1704T were 4.73 (95% CI, 1.51 to 14.77) and 1.73 (95% CI, 0.93 to 3.22), respectively. Certain individual genotype combinations of G82S, 1704G/T, and 2184A/G were significantly associated with the presence of MD (P= .00647) both in diabetic and non-diabetic study populations. The two novel polymorphisms (1704G/T and 2184A/G) together with the G82S were shown to influence the susceptibility to MD independent of diabetes itself.

Bacteriophages of Staphylococcus aureus efficiently package various bacterial genes and mobile genetic elements including SCCmec with different frequencies

Staphylococcus aureus is a serious human and veterinary pathogen in which new strains with increasing virulence and antimicrobial resistance occur due to acquiring new genes by horizontal transfer. It is generally accepted that temperate bacteriophages play a major role in gene transfer. In this study, we proved the presence of various bacterial genes of the S. aureus COL strain directly within the phage particles via qPCR and quantified their packaging frequency. Non-parametric statistical analysis showed that transducing bacteriophages φ11, φ80 and φ80α of serogroup B, in contrast to serogroup A bacteriophage φ81, efficiently package selected chromosomal genes localized in 4 various loci of the chromosome and 8 genes carried on variable elements, such as staphylococcal cassette chromosome SCCmec, staphylococcal pathogenicity island SaPI1, genomic islands vSaα and vSaβ, and plasmids with various frequency. Bacterial gene copy number per ng of DNA isolated from phage particles ranged between 1.05 × 10(2) for the tetK plasmid gene and 3.86 × 10(5) for the SaPI1 integrase gene. The new and crucial finding that serogroup B bacteriophages can package concurrently ccrA1 (1.16 × 10(4)) and mecA (1.26 × 10(4)) located at SCCmec type I into their capsids indicates that generalized transduction plays an important role in the evolution and emergence of new methicillin-resistant clones.

Treatment of consecutive patients with chronic myeloid leukaemia in the cooperating centres from the Czech Republic and the whole of Slovakia after 2000 – a report from the population‐based CAMELIA Registry

Background: Most results on the treatment of chronic myeloid leukaemia (CML) with imatinib were obtained from clinical trials that may differ from the routine practice. We report the results of treatment of consecutive patients with CML at ten major centres during 2000–2008. Patients and methods: Data reporting was retrospective in 2000–2004 and prospective from 2005 on. A total of 661 patients [301 women and 360 men; median age 51 (range, 15–83)] with Ph + CML were registered. The median follow‐up was 46.1 months (0–122.2). Results: Most patients were treated with first‐ (379; 57.3%) or second‐line (193; 29.2%) imatinib; some of the patients underwent allogeneic hematopoietic stem cell transplantation (AHSCT) (83; 12.6%), but 6.1% were treated with other modalities [40 patients; median age 66 (range, 32–83)]. The probability of overall survival (OS) at 5 years, according to Kaplan and Meier, was 88.9%, 77.5% and 68.7% for chronic‐phase patients treated with first‐line imatinib, second‐line imatinib and first‐line AHSCT, respectively, but only 25.2% for patients receiving other modalities. The OS was dependent on the disease phase and Sokal, Hasford and European group for blood and marrow transplantation (EBMT) risk scores (P < 0.001; each). Only 46.2% of deaths in patients treated with other modalities were attributable to CML. Elderly patients over 65 years achieved similar response rates and progression‐free survival to the younger ones. There was a trend for inferior results of AHSCT performed after the failure of imatinib (P = 0.075), probably as a result of differences in EBMT risk scores (P < 0.001). Conclusions: The ability to achieve results comparable to those of previous clinical studies in our CML cohort was influenced by centralised care. Decisions not to initiate imatinib or to delay AHSCT may have a negative impact on OS, but comorbidities may limit the treatment potential of imatinib in the elderly.

Gene polymorphisms (G82S, 1704G/T, 2184A/G and 2245G/A) of the receptor of advanced glycation end products (RAGE) in plaque psoriasis.

Abstract. Having in mind the relationships among oxidative stress, psoriasis and common disorders, the association between polymorphisms in the gene encoding the receptor for advanced glycation end products (RAGE) and plaque psoriasis, including patients with a personal history of diabetes mellitus, cardiovascular disorders, cancer and allergy, was investigated. The allele frequencies and genotype distribution combinations of the four polymorphisms in the RAGE gene (6p21.3, G82S, 1704G/T, 2184A/G and 2245A/G) were compared in a case-control study of 272 subjects (130 patients with plaque psoriasis and 142 healthy control subjects of comparable age and sex distribution). The polymerase chain reaction with subsequent restriction analysis was used for detection of genotype variants. There was a significantly higher frequency of the 2184G allele of the 2184A/G RAGE polymorphism in psoriatic patients than in the control subjects (odds ratio 2.18, 95% CI 1.32–3.59, P=0.001). The 2184G allele occurred more often in psoriatic patients with a negative history of cardiovascular diseases (odds ratio 2.38, 95% CI 1.35–4.18, P=0.001, Pcorr=0.004), in those with a negative history of diabetes mellitus (odds ratio 2.05, 95% CI 0.1.22–3.45, P=0.004, Pcorr=0.012) and in those with a negative history of cancer (odds ratio 1.97, 95% CI 1.17–3.31, P=0.007, Pcorr=0.014) compared with the corresponding control subjects. We conclude that the 2184G allele of the RAGE gene is a significant risk factor for plaque psoriasis. The risk is associated with the non-presence of some common, especially cardiovascular, diseases in psoriatic patients.

Duration of Non-Insulin-Dependent Diabetes mellitus and the TNF-β NcoI Genotype as Predictive Factors in Proliferative Diabetic Retinopathy

The object of the study was to investigate the share of the polymorphisms I/D ACE, endothelin 1 4127G/A and TNF-β NcoI in the susceptibility to proliferative diabetic retinopathy (PDR) in non-insulin-dependent diabetes mellitus (NIDDM). Genotypes were detected by polymerase chain reactions and determined in a set of 246 Caucasian NIDDM subjects with defined PDR status. The relevance of genotypes and clinical characteristics to the PDR occurrence was tested using multiple linear regression models and discrimination analysis. The best predictive value for PDR was given by a combination of two parameters – NIDDM duration and the TNF-β genotype (p < 1·10–6 and p = 1·10–2, respectively) with a correct retrograde prediction of 82.6%. A comparison of the TNF-β NcoI allele frequencies revealed no difference between NIDDM and nondiabetic subjects (n = 176), but a statistically significant difference was found between PDR and non-PDR NIDDM subjects (after a correction for the number of comparisons p = 0.03), allele β2 being associated with PDR. Our results identified the allele variant TNF-β2 being associated with PDR in NIDDM. Diabetes duration and the TNF-β NcoI genotype were proven to significantly predict PDR occurrence. The TNF-β2 allele could be regarded as a separate genetic risk factor that increases the relative incidence of PDR in patients with NIDDM.

Lack of an Association of a Single Nucleotide Polymorphism in the Promoter of the Matrix Metalloproteinase-1 Gene in Czech Women with Pregnancy-Induced Hypertension.

In preeclampsia the cytotrophoblast invasion of the decidual vessels is reduced. The endothelia in the decidual vessels may influence cytotrophoblast invasion and remodeling of decidual spiral arteries. The decidual endothelial cells from preeclamptic placentas produce less matrix metalloproteinase-1 (MMP1) than those from normal placentas. MMPs form a group of enzymes that are capable of degrading components of extracellular matrix. The present study investigated the prevalence and possible association of an insertion of guanine in the promoter of the MMP1 gene in pregnancy-induced hypertension, preeclampsia and eclampsia in the Czech population. This was a case-control study. No differences were observed in genotype frequencies between cases and controls. The insertion of the guanine in the promoter of the MMP1 gene does not appear to increase the risk of development of pregnancy-induced hypertension, preeclampsia and eclampsia.

Relation between the insertion/deletion polymorphism in the gene coding for receptor associated protein (RAP) and plasma apolipoprotein AI (apoAI) and high-density lipoprotein cholesterol (HDL) levels.

In summary, the presented data indicate that a common polymorphism in the LRPAP1 gene coding for RAP is associated with variations in the plasma concentration of apoAI and HDL in Czech CAD patients.

ADMA, SDMA and L-arginine/ADMA ratio but not DDAH genetic polymorphisms are reliable predictors of diabetic nephropathy progression as identified by competing risk analysis.

Background/Aims: Complex interplay of genetic and (patho)physiological factors influence availability of nitric oxide during the development and progression of diabetic complications. We assessed predictive value of commonly studied methylated asymmetric and symmetric dimethylarginines (ADMA and SDMA) and selected single nucleotide polymorphisms (SNPs) in dimethylarginine dimethylaminohydrolase (DDAH) 1 and 2 genes for the progression of diabetic nephropathy (DN). Methods: A total of 341 type 1 and type 2 diabetes patients with variable degree of kidney disease were included at baseline. Plasma levels of ADMA, SDMA and L-arginine were measured and six tagging SNPs in DDAH1 and 2 were determined. Progression of DN was defined as a transition from any given stage to a more advanced stage of albuminuria. Competing risk analysis was applied. Results: Plasma levels of ADMA and SDMA significantly correlated with GFR. No significant genotype-phenotype relationship was ascertained for ADMA and DDAH variants, but SNP rs805304 exhibited marginally significant association with DN. ADMA, SDMA and L-arginine/ADMA ratio standardised to GFR were identified as significant predictors of DN progression but not GFR decline using multivariate competing risk analysis. Conclusions: In our study we confirmed potentially significant role of ADMA and SDMA for the assessment of risk of DN progression in European diabetic population.

Imatinib mesylate efficacy in 72 previously treated Philadelphia-positive chronic myeloid leukemia patients with and without additional chromosomal changes: single-center results.

Reported here are 72 previously treated Philadelphia chromosome-positive (Ph+) CML patients on imatinib (IM) therapy, with a focus on patients with additional chromosomal aberrations (CAs). At the start of IM treatment, 49 patients exhibited only the Ph chromosome (68%) and 23 patients (32%) had one or more additional CAs. The most frequent additional changes were deletions on the der(9q) (8 of 23), trisomy 8 (3 of 23), and an extra copy of the Ph chromosome (2 of 23). Five patients had a complex karyotype. At the latest follow-up, 49 of the 72 patients (68%) were alive, including 15 of the 23 patients with additional CAs (65%). Median follow-up was 6.6 years; median duration of IM treatment was 4.4 years. In all, 35 of the 49 patients with Ph only (71%) and 10 of the 23 patients with additional CAs (43%) achieved complete cytogenetic response. All patients with deletion on der(9q) achieved complete cytogenetic response. There was no statistically significant difference in the overall survival of patients with additional CAs and patients with Ph as the sole abnormality. Patients in accelerated phase had significantly worse overall survival on IM, regardless of additional CAs. The present results confirm that the majority of previously treated Ph+ CML patients benefit from starting IM therapy, including patients with defined additional changes. In contrast, patients with complex karyotypes have poor prognosis, even with IM.

Trends in stage-specific population-based survival of cancer patients in the Czech Republic in the period 2000-2008

BACKGROUND The objective of this study was to assess trends in overall and in stage-specific 5-year relative survival rates of the Czech cancer patients between periods 2000-2004 and 2005-2008. METHODS All Czech cancer patients diagnosed between 1995 and 2008 were included in the analysis. Period analysis was employed to calculate 5-year relative survival for 21 cancers. RESULTS Significant improvements in crude 5-year relative survival for 14 of 21 assessed types of cancer, including the most frequent diagnoses, such as, colorectal, prostate, breast, lung, kidney, pancreatic, and bladder cancer and melanoma, were identified. Moreover, in case of colorectal, lung, and prostate cancer, improvement in stage-specific 5-year relative survival was confirmed as statistically significant for all clinical stages. No diagnosis showed significant decrease in the 5-year relative survival. However, the 5-year relative survival remained poor in patients with metastatic cancers at diagnosis, particularly in case of liver, pancreatic, lung, and oesophageal cancer. CONCLUSIONS The cancer-specific outcomes in the Czech Republic are improving. Nevertheless, despite the overall significant improvement in 5-year relative survival of most of the cancer diagnoses, the high proportion of patients primarily diagnosed with metastatic cancer still represents a substantial challenge for prevention and early detection.