Validation of a Genomic Classifier in the NRG Oncology/RTOG 0521 Phase III Trial of Docetaxel with Androgen Suppression and Radiotherapy for Localized High-Risk Prostate Cancer

PURPOSE/OBJECTIVE(S)

Decipher is a prognostic genomic classifier (GC) validated in several prospective NRG Oncology Phase III trials. Herein, we validate the GC in pre-treatment biopsy samples for risk stratification in a cohort of high-risk men treated with definitive radiotherapy and androgen suppression with or without docetaxel chemotherapy.

MATERIALS/METHODS

As per a pre-specified and approved NCI analysis plan (Navigator #1061), we obtained available formalin-fixed paraffin-embedded tissue from biopsy specimens from the NRG biobank from patients enrolled on the NRG/RTOG 0521 randomized phase III trial. After central review, the highest-grade tumors were profiled on clinical-grade whole-transcriptome arrays (Veracyte, San Diego, CA) and GC scores were obtained. Pre-specified categorical GC scores, adjusted for archival tissue analysis, were used to define higher (>0.46) and lower (≤0.46) risk groups. The primary objective was to validate the independent prognostic ability of GC for metastasis-free survival (MFS) with Cox multivariable analyses (MVA).

RESULTS

Samples were obtained from 283 consented, evaluable patients with tissue (50% of trial) yielding 183 (65%) GC scores that passed quality metrics, 91 from control and 92 from the interventional arm. Median age was 66 years, median PSA was 19.3 ng/uL (IQR: 8.1-41.4), 81% had clinical stage ≥T2 and 80% had Gleason score ≥8 (47% ≥9). Median GC score was 0.55 (IQR: 0.38-0.78) and overall the arms were balanced for key covariates. With a median follow-up of 9.9 years (IQR: 9.3, 10.7), 67 MFS events including 34 distant metastases (DM) were observed. On MVA, only the GC (per 0.1 unit) was independently associated with MFS (HR 1.12, 95% CI 1.01-1.25) as well as DM (sHR 1.22, 95% CI 1.06-1.41), whereas the 4 pre-defined trial risk groups used for stratification (based on Gleason score, T-stage and PSA), randomization and patient age were not. For categorical GC, on MVA, higher-risk GC patients (65%) had worse DM (sHR 2.82, 95% CI 1.1-7.3) compared to those with lower GC. Cumulative incidence of DM at 10-years was 27% for higher GC vs 9% (95% CI 7-18%) for lower GC. No biomarker-by-treatment interaction with GC and the addition of docetaxel was detected.

CONCLUSION

In pre-treatment biopsy samples from a randomized Phase 3 trial cohort, GC demonstrated its ability to further risk stratify clinically high-risk men demonstrating an independent association of GC score with DM and MFS. High-risk prostate cancer is a heterogeneous disease state and GC can improve risk stratification to help personalize shared decision-making. NRG-GU009/PREDICT-RT (NCT04513717) aims to determine the optimal therapy based on GC score for high-risk prostate cancer.

Prognostic Significance of Pretreatment Immune Cell Infiltration in Muscle Invasive Bladder Cancer Treated with Definitive Chemoradiation: Analysis of NRG RTOG 0524 and 0712

PURPOSE/OBJECTIVE(S)

Chemoradiation therapy (CRT) is an organ conserving approach in the treatment of locally advanced bladder cancer. Chemoradiation is thought to potentially result in immunogenic stimulation, and bladder cancer is often a tumor with high immune cell infiltration. Thus, we aimed to profile the tumor immune microenvironment of bladder cancer and identify prognostic immune biomarkers for CRT response by profiling tumor samples from NRG/RTOG 0524 and 0712, two prospective trials of CRT in muscle invasive bladder cancer (MIBC).

MATERIALS/METHODS

Pretreatment tissue samples from both trials were profiled using Cofactor Genomics ImmunoPrism, an RNA sequencing assay that uses gene expression profiles to quantify immune cell populations in the tumor microenvironment (TME). Differential gene expression was estimated for different immune cell type proportions across samples. Kaplan-Meier survival analysis and log rank tests were performed to evaluate differences in overall survival (OS) stratified by genes influenced by immune cell proportions or genes associated with immune response signatures.

RESULTS

A total of 70 samples (43 from RTOG 0524 and 27 from RTOG 0712) underwent analysis using the ImmunoPrism assay. Immune cell proportions were as follows: CD8 T cells: median 1.2%, CD4 T cells: median 0.8%, Treg cells: median 9.2%, CD19 B cells: median 5.1%, M2 macrophages: median 0.8%, M1 macrophages: median 0%. Unbiased clustering based on gene expression profiles driven by immune cell proportions demonstrated two groups: cluster 1 with a low percentage of immune cells and shorter OS (median 31 months) and cluster 2 with a high percentage of immune cells and longer OS (median 101 months, p = 0.036). Higher expression of genes associated with T cell infiltration (CD8A and ICOS) was associated with improved OS (104 vs 35 months, p = 0.028, HR = 0.48 (0.25 - 0.94), p = 0.031) as was higher expression of IDO1, which is associated with the interferon gamma pathway (104 vs 35 months, p = 0.042, HR = 0.49 (0.24 - 0.99), p = 0.046).

CONCLUSION

Bladder tumors have a wide range of immune cell infiltration in the TME. Increased immune cell proportions are prognostic for OS following CRT, as well as a higher expression of genes associated with T cell infiltration interferon gamma signaling. These findings have implications for the integration of immunotherapy in the definitive management of MIBC; and can be explored further in the ongoing NRG/SWOG 1806 trial.

Prognostic value of Ki67 in localized prostate carcinoma: a multi-institutional study of >1000 prostatectomies

BACKGROUND

Expanding interest in and use of active surveillance for early state prostate cancer (PC) has increased need for prognostic biomarkers. Using a multi-institutional tissue microarray resource including over 1000 radical prostatectomy samples, we sought to correlate Ki67 expression captured by an automated image analysis system with clinicopathological features and validate its utility as a clinical grade test in predicting cancer-specific outcomes.

METHODS

After immunostaining, the Ki67 proliferation index (PI) of tumor areas of each core (three cancer cores/case) was analyzed using a nuclear quantification algorithm (Aperio). We assessed whether Ki67 PI was associated with clinicopathological factors and recurrence-free survival (RFS) including biochemical recurrence, metastasis or PC death (7-year median follow-up).

RESULTS

In 1004 PCs (∼4000 tissue cores) Ki67 PI showed significantly higher inter-tumor (0.68) than intra-tumor variation (0.39). Ki67 PI was associated with stage (P<0.0001), seminal vesicle invasion (SVI, P=0.02), extracapsular extension (ECE, P<0.0001) and Gleason score (GS, P<0.0001). Ki67 PI as a continuous variable significantly correlated with recurrence-free, overall and disease-specific survival by multivariable Cox proportional hazard model (hazards ratio (HR)=1.04-1.1, P=0.02-0.0008). High Ki67 score (defined as ⩾5%) was significantly associated with worse RFS (HR=1.47, P=0.0007) and worse overall survival (HR=2.03, P=0.03).

CONCLUSIONS

In localized PC treated by radical prostatectomy, higher Ki67 PI assessed using a clinical grade automated algorithm is strongly associated with a higher GS, stage, SVI and ECE and greater probability of recurrence.

Guidelines for complex genetic analysis of hereditary breast ovarian cancer syndrome in slovak population

Genetic diagnostics of hereditary breast and ovarian cancer (HBOC) has been performed in Slovakia in many different forms before the year 2000. Complex HBOC genetic analysis consists of many steps, including the initial genetic consultation, laboratory testing of genes associated with HBOC, interpretation and report of DNA analysis results, secondary explanatory genetic consultation and recommendation of clinical management for pathological mutation carriers. Many clinicians are participating on this workflow, such as clinical geneticists, laboratory diagnosticians as well as gynaecologists, oncologists or radio-diagnosticians. Currently, genetic testing is still technically and financially demanding and aimed only at selected families or patients who fulfil the defined clinical indication criteria.

Positive result of DNA analysis, that is, detection of pathological mutation in genes associated with HBOC syndrome means that the risk of breast/ovarian cancer onset in mutation carriers is amplified. This predisposition markedly affects the clinical management and treatment of patient and other members of the family, thus creating the demand to establish widely accepted specific recommendations for genetic diagnostics of HBOC. In the past, the analysis of HBOC in Slovakia followed various technical approaches and indication criteria depending on the workflow of specific laboratory. The guidelines reported below adhere to the current trends in DNA analysis and clinical healthcare, define the criteria for diagnostic laboratories, conditions for genetic testing and determine indications for selection of HBOC families and further clinical management of mutation carriers.

Defects of genes encoding inhibitors of coagulation and their application in early miscarriage aetiology

Properly functioning coagulation in gravidity is not necessary only to provide the continuity of circulation in placenta. Today we recognize that proteins and cells of haemostasis in the maternal blood cooperate with the components of a coagulation cascade produced by embryonic trophoblast cells. Such coordination on the embryomaternal interface is necessary for an intact embryogenesis. Other findings discuss the ability of coagulation components to act also outside the hemocoagulation process, especially as signal molecules, regulators of immune reactions, cell proliferation and others. Haemostasis is thus a complex system and we still do not know all of its pathways. This is perhaps also the reason that in the case of known procoagulant mutations (FV Leiden, gene mutation for prothrombine G20210A) we cannot explain why some carriers suffer recurrent miscarriages and others have uncomplicated pregnancies. The expert community believes that the phenotype manifestation of these mutations in terms of pregnancy losses could be connected to the simultaneous presence (synergistic effect) of other polymorphisms of gene-encoding proteins of haemostasis or the lack thereof (antagonistic effect) (Ref. 59).

Genomic copy number alterations in clear cell renal carcinoma: associations with case characteristics and mechanisms of VHL gene inactivation

Array comparative genomic hybridization was used to identify copy number alterations in clear cell renal cell carcinoma (ccRCC) patient tumors to identify associations with patient/clinical characteristics. Of 763 ccRCC patients, 412 (54%) provided frozen biopsies. Clones were analyzed for significant copy number differences, adjusting for multiple comparisons and covariates in multivariate analyses. Frequent alterations included losses on: 3p (92.2%), 14q (46.8%), 8p (38.1%), 4q (35.4%), 9p (32.3%), 9q (31.8%), 6q (30.8%), 3q (29.4%), 10q (25.7%), 13q (24.5%), 1p (23.5%) and gains on 5q (60.2%), 7q (39.6%), 7p (30.6%), 5p (26.5%), 20q (25.5%), 12q (24.8%), 12p (22.8%). Stage and grade were associated with 1p, 9p, 9q, 13q and 14q loss and 12q gain. Males had more alterations compared with females, independent of stage and grade. Significant differences in the number/types of alterations were observed by family cancer history, age at diagnosis and smoking status. Von Hippel–Lindau (VHL) gene inactivation was associated with 3p loss (P<E-05), and these cases had fewer alterations than wild-type cases. The fragile site flanking the FHIT locus (3p14.2) represented a unique breakpoint among VHL hypermethylated cases, compared with wild-type cases and those with sequence changes. This is the first study of its size to investigate copy number alterations among cases with extensive patient, clinical/risk factor information. Patients characterized by VHL wild-type gene status (vs sequence alterations) and male (vs female) cases had more copy number alterations regardless of diagnostic stage and grade, which could relate to poor prognosis.

Genetic and epigenetic regulation of the organic cation transporter 3, SLC22A3

Human organic cation transporter 3 (OCT3 and SLC22A3) mediates the uptake of many important endogenous amines and basic drugs in a variety of tissues. OCT3 is identified as one of the important risk loci for prostate cancer, and is markedly underexpressed in aggressive prostate cancers. The goal of this study was to identify genetic and epigenetic factors in the promoter region that influence the expression level of OCT3. Haplotypes that contained the common variants, g.-81G>delGA (rs60515630) (minor allele frequency 11.5% in African American) and g.-2G>A (rs555754) (minor allele frequency>30% in all ethnic groups) showed significant increases in luciferase reporter activities and exhibited stronger transcription factor-binding affinity than the haplotypes that contained the major alleles. Consistent with the reporter assays, OCT3 messenger RNA expression levels were significantly higher in Asian (P<0.001) and Caucasian (P<0.05) liver samples from individuals who were homozygous for g.-2A/A in comparison with those homozygous for the g.-2G/G allele. Studies revealed that the methylation level in the basal promoter region of OCT3 was associated with OCT3 expression level and tumorigenesis capability in various prostate cancer cell lines. The methylation level of the OCT3 promoter was higher in 62% of prostate tumor samples compared with matched normal samples. Our studies demonstrate that genetic polymorphisms in the proximal promoter region of OCT3 alter the transcription rate of the gene and may be associated with altered expression levels of OCT3 in human liver. Aberrant methylation contributes to the reduced expression of OCT3 in prostate cancer.

Regression of left ventricular hypertrophy and aortic remodelling in NO-deficient hypertensive rats: effect of L-arginine and spironolactone

AIM

We investigated, whether the substrate for nitric oxide (NO) formation -L-arginine - and the aldosterone receptor antagonist - spironolactone - are able to reverse alterations of the left ventricle (LV) and aorta in N(omega)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension.

METHODS

Six groups of male adult Wistar rats were investigated: controls after 4 and 7 weeks of experiment, rats treated with L-NAME for 4 weeks and three recovery groups: spontaneous-reversion (4 weeks L-NAME + 3 weeks placebo), spironolactone-induced reversion (4 weeks L-NAME + 3 weeks spironolactone) and L-arginine-induced reversion (4 weeks L-NAME+ 3 weeks L-arginine). Blood pressure was measured by tail-cuff plethysmography. Relative weight of the LV, myocardial fibrosis (based upon histomorphometry and hydroxyproline determination) and conjugated dienes in the LV and aortic cross-sectional area, inner diameter and wall thickness were determined. NO-synthase activity was investigated in the LV and aorta.

RESULTS

L-NAME administration induced hypertension, left ventricular hypertrophy (LVH), LV fibrosis, aortic thickening and diminution of NO-synthase activity in the LV and aorta. Reduction in blood pressure and regression of LVH were observed in all recovery groups, yet reduction in LV fibrosis and aortic thickening were not. NO-synthase activity was restored only in the L-arginine and spironolactone group.

CONCLUSION

In our study, the reversion of hypertension and LVH was not dependent on the restoration of NO-synthase activity. Moreover, LV fibrosis and aortic remodelling seem to be more resistant to conditions resulting in regression of LVH. Preserved level of fibrosis in the initial period of LVH regression might result in loss of structural homogeneity and possible functional alterations of the LV.

Carbamazepine and risk of hypothyroidism: a prospective study

OBJECTIVES - While carbamazepine (CBZ) decreases thyroid hormone concentrations it rarely causes hypothyroidism. We assessed prospectively the early effect of CBZ on thyroid status in thyroxine-supplemented hypothyroid patients, when compared with patients without a thyroid disorder. METHODS - In 29 patients, thyrotropin (TSH), total thyroxine (TT4) and free thyroxine (FT4) serum levels were assayed before starting CBZ, and then weekly for 7 weeks. Nineteen patients with no thyroid disorder (group A) were compared with 10 thyroxine-supplemented hypothyroid patients, stable before CBZ treatment (group B). RESULTS - In group A, TT4 decreased significantly by ca. 15-25%, starting from the first week (Friedman, P < 0.001). FT4 decline was smaller (ca. 10-15%) and delayed till the second week. FT4/TT4 ratio increased significantly (P < 0.001), while TSH only slightly (P = 0.073), never exceeding normal range. In group B, similar TT4 and FT4 decline was followed by significantly increasing TSH (P = 0.011), while the FT4/TT4 ratio was not significantly changed. In 3 of 10 patients TSH rose over 5 mIU/l, necessitating treatment adjustment. CONCLUSIONS - In patients with no thyroid disorder, CBZ causes hormonal changes of no clinical relevance, due to adaptive response. In T4-supplemented hypothyroid patients this adaptation is lacking, CBZ may precipitate subclinical or overt hypothyroidism, and early thyroid function monitoring seems advisable.

Morphological features of TMPRSS2-ERG gene fusion prostate cancer

The TMPRSS2-ETS fusion prostate cancers comprise 50-70% of the prostate-specific antigen (PSA)-screened hospital-based prostate cancers examined to date, making it perhaps the most common genetic rearrangement in human cancer. The most common variant involves androgen-regulated TMPRSS2 and ERG, both located on chromosome 21. Emerging data from our group and others suggests that TMPRSS2-ERG fusion prostate cancer is associated with higher tumour stage and prostate cancer-specific death. The goal of this study was to determine if this common somatic alteration is associated with a morphological phenotype. We assessed 253 prostate cancer cases for TMPRSS2-ERG fusion status using an ERG break-apart FISH assay. Blinded to gene fusion status, two reviewers assessed each tumour for presence or absence of eight morphological features. Statistical analysis was performed to look for significant associations between morphological features and TMPRSS2-ERG fusion status. Five morphological features were associated with TMPRSS2-ERG fusion prostate cancer: blue-tinged mucin, cribriform growth pattern, macronucleoli, intraductal tumour spread, and signet-ring cell features, all with p-values < 0.05. Only 24% (n=30/125) of tumours without any of these features displayed the TMPRSS2-ERG fusion. By comparison, 55% (n=38/69) of cases with one feature (RR=3.88), 86% (n=38/44) of cases with two features (RR=20.06), and 93% (n=14/15) of cases with three or more features (RR=44.33) were fusion positive (p<0.001). To our knowledge, this is the first study that demonstrates a significant link between a molecular alteration in prostate cancer and distinct phenotypic features. The strength of these findings is similar to microsatellite unstable colon cancer and breast cancer involving BRCA1 and BRCA2 mutations. The biological effect of TMPRSS2-ERG overexpression may drive pathways that favour these common morphological features that pathologists observe daily. These features may also be helpful in diagnosing TMPRSS2-ERG fusion prostate cancer, which may have both prognostic and therapeutic implications.

Preliminary evaluation of prostate cancer metastatic risk biomarkers

Prostate cancer patients at high risk of metastasis need to be identified as early as possible since metastasis is invariably fatal. Treatment could be tailored to risk. Recent array comparative genomic hybridization (aCGH) studies of primary and metastatic prostate tumors identified 39 BAC clones capable of detecting genomic signatures of metastasis. We termed these loci the genomic evaluators of metastatic CaP (GEMCaP). Risk assessments were made on a set of men who were managed with radical prostatectomy. We compared the utility of GEMCaP loci and the Kattan nomogram, a common risk assessment tool, in relation to biochemical outcome. This preliminary evaluation experiment suggests we can use aCGH to detect genomic signatures of metastasis in primary tumors with an accuracy of 78%. The classification accuracy for the Kattan nomogram was 75%. Therefore, validation of GEMCaP is warranted in a larger, appropriately designed cohort.

L-arginine fails to protect against myocardial remodelling in L-NAME-induced hypertension

BACKGROUND

We investigated whether the substrate for nitric oxide synthesis L-arginine is able to modify hypertension and left ventricular hypertrophy development induced by chronic blockade of nitric oxide synthase activity by NG-nitro-L-arginine-methyl ester (L-NAME).

MATERIAL AND METHODS

Four groups of rats were investigated: control, L-arginine 1.5 g kg-1, L-NAME 40 mg kg-1, and L-NAME +L-arginine in corresponding doses. Systolic blood pressure was measured by non-invasive tail-cuff plethysmography each week. After 4 weeks, the animals were sacrificed and hydroxyproline and coenzyme Q9 and Q10 concentrations in the left ventricle, and nitric oxide synthase activity in the left ventricle, kidney and brain were investigated.

RESULTS

In the L-NAME group, nitric oxide synthase activity was decreased in the left ventricle, kidney and brain, and hypertension, left ventricular hypertrophy and fibrosis developed. Heart remodelling was associated with the decrease of coenzyme Q9 and Q10 concentrations in the left ventricle. Simultaneous treatment with L-NAME and L-arginine prevented nitric oxide synthase activity diminution in the left ventricle but not in the kidney and brain, and completely failed to prevent hypertension, left ventricular hypertrophy and fibrosis. Nevertheless, l-arginine prevented the diminution of coenzyme Q9 and Q10 concentrations in the left ventricle.

CONCLUSIONS

We conclude that L-arginine failed to prevent hypertension, left ventricular hypertrophy and fibrosis development despite restoration of nitric oxide synthase activity in the left ventricle. However, L-arginine prevented the diminution of coenzyme Q levels in the left ventricle.

["Nested" PCR for human papillomavirus detection and typing in samples from cervical lesions of gynecological patients]

OBJECTIVE

The authors tested PCR--so called nested (N-PCR) for the detection of HPV in cervical lesions of uterus. This method is based on repeated amplification of specific viral DNA fragments. The sensitivity of N-PCR was compared to the sensitivity of the hybridization method. In the second part of the experiment positive samples underwent HPV typing by PCR.

BACKGROUND

The effectiveness of N-PCR for HPV detection was verified on 30 samples from cytologically/histologically suspected cervical lesions. In these cases, previous detection by hybridization method was unsuccessful. The second group consisted of 21 samples acquired by conisation, in which HPV presence was confirmed by hybridization method. Post surgery HPV detection using hybridization technique was negative in this group of patients.

RESULTS

By means of N-PCR the presence of HPV DNA was confirmed in all 30 samples from the first group (100%) and in 8 (38%) cases from the group of samples obtained after conisation. Type-specific PCR detection indicated HPV type 16 in 20 cases, HPV type 18 in 6 cases (from the first series). In the remaining 4 cases typing for HPV 16, 18, 31 and 33 was negative. In the second series all 8 samples were HR-HPV type 16.

CONCLUSION

At the present time, N-PCR is probably the most sensitive HPV detection method. The only real disadvantages of the given technique are relatively high costs of diagnostics equipment and the requirement of highly qualified personel.

ACE-inhibition and angiotensin II receptor blockers in chronic heart failure: pathophysiological consideration of the unresolved battle

Reducing the effects of angiotensin II by blockade of AT1-receptors may be superior to inhibition of angiotensin II formation by angiotensin converting enzyme (ACE) inhibitors in chronic heart failure (CHF) patients. However, the results of several trials did not fulfil this expectation. In both ELITE II with symptomatic CHF patients and in OPTIMAAL involving high risk patients after acute myocardial infarction, angiotensin II type I (AT1) receptor blocker (ARB) losartan did not prove to be superior to captopril. There are several potential reasons, why ARBs did not fare better than ACE inhibitors. Although AT1-receptor blockade may block the effects of non-ACE pathways of tissue angiotensin II formation, no clinical evidence is available that a more powerful inhibition of the tissue renin-angiotensin system brings improved survival. The choice of patients for clinical trials of HF therapy is not based on the level of neurohumoral activation. Thus, the more effective attenuation of angiotensin II action with ARBs may not bring additional benefits. The potential antiremodeling effect of ARBs through the stimulation of AT2 receptors by angiotensin II could be counterbalanced by a failure of AT1-receptor blockers to enhance bradykinin, nitric oxide and prostacyclin formation with antigrowth properties. Although ACE-inhibitors seem to have slightly better results at present than AT1 blockers in the battle on heart failure patient, future trials will decide which is the definitive winner.

The effect of nickel sulphate, potassium dichromate, cobalt nitrate and cadmium sulphate on the proteins of cellular contacts and actin skeleton of cultivated human keratinocytes

The authors tested the effects of known allergens, namely nickel sulphate, potassium dichromate, cobalt nitrate and cytotoxic cadmium sulphate on the proteins of cellular contacts (vinculin, talin, E-cadherin, desmoplaktin) and actin cytoskeleton (actin filaments) of cultivated human keratinocytes. The localisation of proteins of cellular contacts was detected by means of direct immunofluorescence. The authors have detected a decrease in, and destruction of cellular contact proteins and actin cytoskeleton after testing the effect of all allergens, while the most significant changes were detected in E-cadherin, vunkulin and actin filaments. Desmoplaktin and talin were less damaged. Potassium dichromate caused damage already in concentration of 1 microg/ml. A similar effect of the other two tested haptanes was brought about in concentration being 100-fold higher.

CONCLUSION

the gained results indicate that the investigation of cellular contact proteins and actin cytoskeleton of cultivated human keratinocytes can possibly become a part of the testing of allergy-triggering potential of chemical substances. (Tab. 1, Fig. 4, Ref. 18.)

[Diagnosis of Chlamydia trachomatis using PCR in gynecology patients in Slovakia]

The authors examined using the polymerase chain reaction (PCR) more than 2700 gynaecological patients for the presence of Ch. tracheomatis. The patients were mostly from Bratislava and surroundings. The material used were cervical smears or morning urine. The most frequent diagnoses associated with Chlamydia infection were adnexitis (38%), cervicitis (22%), pelvic pain (9%), sterility (9%), cystitis and ureteritis (3%) abortus imminenes (4%) partus prematurus imminenes (9%). There was a marked seasonal character of chlamydias with the peak during the summer period. The mean age of the patients was 29.2 years and thus the assumed higher incidence of younger age groups was not confirmed. PCR proved to be an accurate, reliable and perspective method for the detection of Ch. trachomatis in Slovak gynaecological patients.

[The significance of aldosterone in chronic heart failure: the RALES study]

Reduction of excessive neurohumoral activation in chronic heart failure (CHF) improves the prognoses. In addition to reduction of angiotensin production or angiotensin II action and the influence of the sympathoadrenal system also blocking of aldosterone effects becomes part of the therapeutic procedure in patients with CHF. Excessive systemic and probably also local aldosterone production promotes undesirable fluid retention, hypokalaemia and hypomagnesaemia, induction of hypertrophy and fibrosis of the heart muscle and blood vessels and the development of endothelial dysfunction, peripheral vasoconstriction and depression of the baroreflex. In addition to classical effects also the existence of a rapid, so-called non-genomic effect of aldosterone is assumed. Adding a blocker of aldosterone receptors to ACE inhibition was not recommended due to possibility development of hyperkalaemia. Later it was revealed that ACE inhibitors are unable to block sufficiently the action of aldosterone and that addition of spironolactone in small amounts to ACE inhibition and diuretics does not cause in patients with CHF a major increase of the potassium level. In the RALES study (Randomized Aldacton Evaluation Study) comprising 1663 patients with serious heart failure (NYHA III, IV) addition of 25 mg spironolactone to standard treatment with ACE inhibitor, diuretic and as rule also digoxin reduced the mortality by another 30% as compared with the addition of placebo. Undesirable effects were minimal. As to potential protective mechanisms of spironolactone the greatest importance is ascribed to the reduction of excessive fibrosis of the heart muscle. Spironolactone reduces the level of the circulating N-terminal aminopeptide procollagen type III the high level of which is associated with deterioration of the prognosis.

[Indirect diagnosis of type I neurofibromatosis using RFLP in Slovak families]

Neurofibromatosis type I clinical diagnosis confirmation as well as antenatal diagnostics of the disease are recently provided by molecular genetics. The authors analyze 17 Slovak families with multiple NFI incidence, in whom the detection of mutated gene transfer was performed using indirect diagnostics-bound with of restrictive fragments length polymorphism RFLP. With the help of PCR 7 polymorphic sequencies were amplified and subsequently broken with restrictive endonucleases localized close to the neurofibrin gene. The system informative capacity was comparable with the results of other Caucasian population studies. Although direct detection of mutation is the perspective of the diagnostics, binding analysis in informative families with multiple incidence of the disease provides reliable and cheaper possibility of NFI diagnostic on the level of DNA analysis. (Tab. 1, Fig. 3, Ref. 26.)

The potential role of nitric oxide in the hypertrophic growth of the left ventricle

Left ventricular hypertrophy (LVH) is the result of interaction between a chronic hemodynamic overload and non-hemodynamic factors. There are several lines of evidence presented in this work suggesting that nitric oxide (NO) may participate in the hypertrophic growth of the myocardium. First, endothelial NO production was shown to be decreased in several types of hemodynamically overloaded circulation both in animals and humans. Second, compounds stimulating NO production were able to diminish the extent or modify the nature of LVH in some models of myocardial hypertrophic growth. Third, arterial hypertension can be induced by inhibition of nitric oxide synthase activity. This NO-deficient hypertension is associated with the development of concentric LVH, myocardial fibrosis and protein remodeling of the left ventricle. The mechanism of LVH development in NO-deficient hypertension is complex and involves decreased NO production and increased activation of the renin-angiotensin-aldosterone system. Cardiovascular protection via ACE inhibition in NO-deficient hypertension may be induced by mechanisms not involving an improvement of NO production. In conclusion, the hypertrophic growth of the LV appears to be the result of interaction of vasoconstrictive and growth stimulating effects of angiotensin II on the one hand and of vasodilating and antiproliferative effects of nitric oxide on the other.

Heart failure and angiotensin converting enzyme inhibition: problems and perspectives

Heart failure has become the most widely studied syndrome in cardiology over the recent years. Despite the encouraging achievements by angiotensin converting enzyme (ACE) inhibitors, the mortality of patients with chronic heart failure remains high. There are several factors which can potentially be responsible for the fact that about 80% of patients with a failing heart defy protection by ACE inhibitors: different activation of tissue and systemic renin-angiotensin system (RAS) in a particular heart disease and the distinct ability of various ACE inhibitors to block cardiac ACE, alternative pathways for angiotensin II formation (chymase), genetic polymorphism of the RAS system and the complexity of neuroendocrine activation. Moreover, chronic heart failure can provoke disturbances in the reactivity of peripheral vessels and metabolism of striated muscles. These factors may then potentiate the vicious circle of heart failure. New therapeutic approaches, which could further reduce the mortality in patients with heart failure involve angiotensin II type 1 receptor antagonists, beta-blockers, aldosterone antagonists and blockers of the endothelin receptor. A number of questions associated with functions of the RAS still remain open and their solution could be of substantial benefit for patients with a failing heart.

Captopril attenuates proteosynthesis in the aorta and decreases endothelaemia in rabbits with aortic insufficiency

The effect of the angiotensin converting enzyme (ACE) inhibitor, captopril, on proteosynthesis in the aorta, acetylcholine-stimulated aortic relaxation and endothelaemia (circulating endothelial cells) was investigated in rabbits with aortic insufficiency. The animals were studied 28 days after experimental intervention. Cardiac volume overload stimulated proteosynthesis in the aorta as reflected by increased ribonucleic acid (RNA) concentration and [14C] leucine incorporation into proteins of the aorta. Moreover, the number of endothelial cells in the blood was increased. The administration of captopril starting from the second day of the haemodynamic overload, partially prevented the increase both in aortic proteosynthesis and in endothelaemia. Despite these alterations, the relaxing ability of the aorta to acetylcholine was not changed either by the haemodynamic overload or by captopril. We conclude that the increase of proteosynthesis in the aorta and of endothelaemia in the early period of chronic cardiac volume overload in rabbits were partially prevented by chronic captopril treatment. Neither aortic insufficiency nor captopril changed the acetylcholine-induced relaxation of the aorta.

[Diagnosis of Duchenne and Becker muscular dystrophy in Slovak patients using multiplex polymerase chain reaction]

The authors of the paper describe the diagnostic method of deletion in the dystrophin gene by means of an improved variant of the polymerase chain reaction--so called multiplex PCR. The authors analyzed a group of 66 patients with developed clinical symptoms of the disease. The deletion screening included 22 exones of the dystrophine gene and it was performed in 5 multiplex PCR reactions. 20 patients yielded a verified deletion which was pre-assessed by Southern's hybridization. The relative simplicity of multiplex PCR which does not require the use of radioisotopes, its low time and financial needs, make this method to represents an appropriate alternative of Southern's hybridization in the assessment of deletion of the dystrophine gene. (Fig. 1, Ref. 19.)

[Presence of Y-specific sequences in patients with Turner syndrome as a presymptomatic marker of increased risk of gonadoblastoma]

The risk of the origin of neoplasms in patients with gonadal dysgenesis and the presence of Y chromosome mosaicism has been known for a long period. The majority of hidden mosaicism is however not detectable by means of cytogenetic methods. The authors of this study deal with the detection of Y specific chromosomal sequences in 86 patients with Turner syndrome by means of polymerase chain reaction (PCR) and compare the results of this method with cytogenetic findings. The presence of Y specific sequences was proven in 8 patients (9.3%) which correlates with the results of several recent studies. In two cases, the Y chromosome fragment was verified also cytogenetically, in five patients, the diagnose was made more accurate at an originally non-specified marker, and in two cases, the cytogenetic examination has assessed the finding of X chromosome only. PCR is a more sensitive and a more precise method of the assessment of Y chromosome mosaicism in patients with Turner syndrome enabling more effectively to single out persons under the risk of rudimentary gonads gonadoblastoma development. (Fig. 5, Ref. 32.)

[Use of molecular genetics in the early diagnosis of familial adenomatous polyposis]

Familial adenomatous polyposis (FAP) is an autosomal dominant hereditary precancerous condition manifested by hundreds to thousands of polyps in the colon and rectum. Practically, with a 100% certainty, patients with FAP develop carcinoma of the colon or rectum. FAP is this the most dangerous sign of a precancerous condition. So far the only possibility of early diagnosis of this disease was rectoscopy or colonoscopy of risk subjects after annual intervals up to advanced age, After localization of the gene responsible for the development of FAP and discovery of its internal structure, possibilities for revealing FAP, decades before the first clinical symptoms appear, were disclosed.

[Body growth in low birth weight premature children up to 5 years of age]

Investigation of the growth in 488 premature infants born with a low birth weight, compared with infants born in term with a birth weight above 2,500 g at the age of 1-5 years. Body weight, height, head circumference and chest circumference were assessed as well as Quetelet-Kaup-Gould and Quetelet-Bouchard index. It was found that premature infants are retarded in the above parameters, as compared with mature infants, still at the life of live years.