SF3B1 mutations correlated to cytogenetics and mutations in NOTCH1, FBXW7, MYD88, XPO1 and TP53 in 1160 untreated CLL patients

We analyzed a large cohort of 1160 untreated CLL patients for novel genetic markers (SF3B1, NOTCH1, FBXW7, MYD88, XPO1) in the context of molecular, immunophenotypic and cytogenetic data. NOTCH1 mutations (mut) (12.3%), SF3B1mut (9.0%) and TP53mut (7.1%) were more frequent than XPO1mut (3.4%), FBXW7mut (2.5%) and MYD88mut (1.5%). SF3B1mut, NOTCH1mut, TP53mut and XPO1mut were highly correlated to unmutated, whereas MYD88mut were associated with mutated IGHV status. Associations of diverse cytogenetic aberrations and mutations emerged: (1) SF3B1mut with del(11q), (2) NOTCH1mut and FBXW7mut with trisomy 12 and nearly exclusiveness of SF3B1mut, (3) MYD88mut with del(13q) sole and low frequencies of SF3B1mut, NOTCH1mut and FBXW7mut. In patients with normal karyotype only SF3B1mut were frequent, whereas NOTCH1mut rarely occurred. An adverse prognostic impact on time to treatment (TTT) and overall survival (OS) was observed for SF3B1mut, NOTCH1mut and TP53 disruption. In multivariate analyses SF3B1mut, IGHV mutational status and del(11q) were the only independent genetic markers for TTT, whereas for OS SF3B1mut, IGHV mutational status and TP53 disruption presented with significant impact. Finally, our data suggest that analysis of gene mutations refines the risk stratification of cytogenetic prognostic subgroups and confirms data of a recently proposed model integrating molecular and cytogenetic data.

Landscape of genetic lesions in 944 patients with myelodysplastic syndromes

High-throughput DNA sequencing significantly contributed to diagnosis and prognostication in patients with myelodysplastic syndromes (MDS). We determined the biological and prognostic significance of genetic aberrations in MDS. In total, 944 patients with various MDS subtypes were screened for known/putative mutations/deletions in 104 genes using targeted deep sequencing and array-based genomic hybridization. In total, 845/944 patients (89.5%) harbored at least one mutation (median, 3 per patient; range, 0-12). Forty-seven genes were significantly mutated with TET2, SF3B1, ASXL1, SRSF2, DNMT3A, and RUNX1 mutated in >10% of cases. Many mutations were associated with higher risk groups and/or blast elevation. Survival was investigated in 875 patients. By univariate analysis, 25/48 genes (resulting from 47 genes tested significantly plus PRPF8) affected survival (P<0.05). The status of 14 genes combined with conventional factors revealed a novel prognostic model ('Model-1') separating patients into four risk groups ('low', 'intermediate', 'high', 'very high risk') with 3-year survival of 95.2, 69.3, 32.8, and 5.3% (P<0.001). Subsequently, a 'gene-only model' ('Model-2') was constructed based on 14 genes also yielding four significant risk groups (P<0.001). Both models were reproducible in the validation cohort (n=175 patients; P<0.001 each). Thus, large-scale genetic and molecular profiling of multiple target genes is invaluable for subclassification and prognostication in MDS patients.

The role of different genetic subtypes of CEBPA mutated AML

The prognostic impact of mutations in the CCAAT/enhancer binding protein α (CEBPA) gene was evaluated in the context of concomitant molecular mutations and cytogenetic aberrations in acute myeloid leukemia (AML). CEBPA was screened in a cohort of 2296 adult AML cases. Of 244 patients (10.6%) with CEBPA mutations, 140 cases (6.1%) were single-mutated (CEBPAsm) and 104 cases (4.5%) were double-mutated (CEBPAdm). Cytogenetic analysis revealed normal karyotype in 172/244 (70.5%) of CEBPAmut cases, whereas in 72/244 cases (29.5%) at least one cytogenetic aberration was detected. Concurrent molecular mutations were seen less frequently in CEBPAdm than in CEBPAsm AML cases (69.2% vs 88.6% P<0.001). In detail, the spectrum of concurrent mutations was different in both groups with the frequent occurrence of GATA1 and WT1 mutations in CEBPAdm patients. In contrast, FLT3-ITD, NPM1, ASXL1 and RUNX1 mutations were detected more frequently in CEBPAsm cases. Favorable outcome was restricted to CEBPAdm cases and remained an independent prognostic factor for a favorable outcome in multivariate analysis (hazard ratio: 0.438, P=0.020). Outcome in CEBPAsm cases strongly depended on concurrent FLT3-ITD. In conclusion, we propose that only CEBPAdm should be considered as an entity in the WHO classification of AML and should be clearly distinguished from CEBPAsm AML.

Parental origin of de novo cytogenetically balanced reciprocal non-Robertsonian translocations

De novo cytogenetically balanced reciprocal non-Robertsonian translocations are rare findings in clinical cytogenetics and might be associated with an abnormal phenotype. Knowledge of the parental origin and mechanisms of formation is still limited. By microdissection of the derivative chromosomes and their normal homologs from metaphases followed by microsatellite-mediated marker analysis we identified 7 cases of paternal and 3 cases of maternal origin in a cohort of 10 patients with de novo cytogenetically balanced reciprocal non-Robertsonian translocations. Neither in the maternal nor in the paternal group of our study parental age seems to be increased. Together with the data from the literature our results confirm that the majority of de novo cytogenetically balanced reciprocal translocations are of paternal origin, but the preponderance does not appear to be as distinct as previously thought and the paternal age does not seem to be necessarily a major contributing factor.

The Interlaboratory RObustness of Next-generation sequencing (IRON) study: a deep sequencing investigation of TET2, CBL and KRAS mutations by an international consortium involving 10 laboratories

Massively parallel pyrosequencing allows sensitive deep sequencing to detect molecular aberrations. Thus far, data are limited on the technical performance in a clinical diagnostic setting. Here, we investigated as an international consortium the robustness, precision and reproducibility of amplicon next-generation deep sequencing across 10 laboratories in eight countries. In a cohort of 18 chronic myelomonocytic leukemia patients, mutational analyses were performed on TET2, a frequently mutated gene in myeloproliferative neoplasms. Additionally, hotspot regions of CBL and KRAS were investigated. The study was executed using GS FLX sequencing instruments and the small volume 454 Life Sciences Titanium emulsion PCR setup. We report a high concordance in mutation detection across all laboratories, including a robust detection of novel variants, which were undetected by standard Sanger sequencing. The sensitivity to detect low-level variants present with as low as 1-2% frequency, compared with the 20% threshold for Sanger-based sequencing is increased. Together with the output of high-quality long reads and fast run time, we demonstrate the utility of deep sequencing in clinical applications. In conclusion, this multicenter analysis demonstrated that amplicon-based deep sequencing is technically feasible, achieves high concordance across multiple laboratories and allows a broad and in-depth molecular characterization of cancer specimens with high diagnostic sensitivity.

Targeted next-generation sequencing detects point mutations, insertions, deletions and balanced chromosomal rearrangements as well as identifies novel leukemia-specific fusion genes in a single procedure

DNA sequence enrichment from complex genomic samples using microarrays enables targeted next-generation sequencing (NGS). In this study, we combined 454 shotgun pyrosequencing with long oligonucleotide sequence capture arrays. We demonstrate the detection of mutations including point mutations, deletions and insertions in a cohort of 22 patients presenting with acute leukemias and myeloid neoplasms. Importantly, this one-step methodological procedure also allowed the detection of balanced chromosomal aberrations, including translocations and inversions. Moreover, the genomic representation of only one of the partner genes of a chimeric fusion on the capture platform also permitted identification of the novel fusion partner genes. Using acute myeloid leukemias harboring RUNX1 abnormalities as a model system, three novel chromosomal fusion sequences and KCNMA1 as a novel RUNX1 fusion partner gene were detected. This assay has the strong potential to become an important method for the comprehensive genetic characterization of particular leukemias and other malignancies harboring complex genomes.

In vitro and in vivo assessment of the antioxidant activity of melatonin and related indole derivatives

Effects of melatonin and some structurally related indole compounds were studied by in vitro methods such as (i) an inhibition of the hyaluronic acid degradation and (ii) a standard lipid peroxidation assay. In vivo approach was based on the alloxan model of hyperglycaemia. Reduction of the viscosity of a hyaluronic acid solution in the reaction mixture was inhibited by tryptamine (91% inhibition), as well as by indole-3-carboxylic acid and indomethacin (80% and 77% inhibition, respectively). Lipid peroxidation with tert-butyl hydroperoxide as a source of radicals was followed by the formation of thiobarbituric acid reactive substances. Tested drugs inhibited lipid peroxidation in the order: tryptamine (59%) > indole-2-carboxylic acid (38%) > indomethacin (26%) > melatonin and indole-3-carboxylic acid (13%). In vivo, alloxan-induced hyperglycaemia was reduced in mice pretreated with drugs tested. The highest protective effect was observed with indomethacin (52% inhibition), followed by tryptamine and melatonin (18% and 16% inhibition, respectively).

Effects of known and potential antioxidants on animal models of pathological processes (diabetes, gastric lesions, allergic bronchospasm)

Highly reactive oxygen-free radicals are implicated in the pathogenic process of various diseases. Using an animal model of diabetes (alloxan-induced hyperglycaemia in mice), a model of gastric ulcer (indomethacin-induced gastric lesion in rats), and a model of bronchial asthma (ovalbumin-induced allergic bronchospasm in guinea pigs), a potential therapeutic effect was tested in known antioxidant drugs (alpha-tocopherol, ubiquinone), the thio-compound mesna, and drugs with a possible antioxidant effect (substances derived from the ergoline structure: 6-hydroxynicotinic acid and 4-hydroxypyridine). The pre-treatment with ubiquinone and 6-hydroxynicotinic acid almost completely prevented alloxan-induced hyperglycaemia (94 and 93% inhibition of hyperglycaemia, respectively). A weaker effect was shown by alpha-tocopherol and 4-hydroxypyridine (31 and 27% inhibition of hyperglycaemia, respectively). Mesna negligibly increased hyperglycaemia. 32% and 21% inhibitions of the number of gastric lesions were shown after administration of 6-hydroxynicotinic acid and alpha-tocopherol, respectively. Other drugs, most markedly mesna, aggravated gastric lesions. The most marked protective effect on ovalbumin-induced bronchospasm was exerted by 6-hydroxynicotinic acid (the pulmonary ventilation was increased by 84% in comparison with control group), while mesna and (alpha-tocopherol had a weaker effect (amelioration by 50 and 51 %, respectively). Ubiquinone and 4-hydroxypyridine aggravated pulmonary ventilation. The most marked protective effect in the animal models used was shown by 6-hydroxynicotinic acid.

Changes in the gastrointestinal tract, cardiovascular function and some drug metabolizing processes in rats and guinea-pigs intoxicated with aflatoxin B1

The effects of aflatoxin B1 (AFB1) on the reactivity of the peripheral vessels, passage through the gastrointestinal system, production of hydrochloric acid and some liver functions were analyzed. The results shown the decreased glucuronidizing ability of the liver (58% of the initial value) accompanied by an increased amount of the unconjugated substrate while glycine conjugation was not changed in animals on the 3rd day after the treatment with AFB1. The uptake of 99mTc-SnO2 colloid was 1.14 times lower in the liver and 1.94 times higher in the spleen in AFB1 treated animals. A lowered activity of the glucuronizing system and a possibly indirectly lowered uptake of tin colloid in the liver indicate the toxic effect of AFB1 in hepatocytes. The other parameters studied were not changed or were changed only slightly.

Preclinical comparison of bis-diketopiperazine-propane (dexrazoxane) and bis-diketopiperazine-ethane (antimet) on the adriamycin-cardiotoxic effect

A cardiotoxic effect induced by adriamycin (by repeated i.v. administration to experimental rats in 7-day intervals of administration) begins to be manifested in the ECG record by prolongation of the S alpha T segment between days 14 and 20, on day 30 it is statistically significant. By means of this index, the known protective effect of dexrazoxane (the preparation Cardioxan) against adriamycin cardiotoxicity has been successfully confirmed in a four-week experiment. A comparative study (using the identical frequency of the dosing scheme and S alpha T segment as the decisive parameter) has revealed that antimet-as another original substance of the diketopiperazines group-also involves (though less significantly) protective effects against the toxic action of adriamycin.

Possible use of excretion of tubular epithelial cells for the study of the nephrotoxic effect of xenobiotics

The method of determination of the minute excretion of tubular epithelial cells renders it possible to investigate the course of the nephrotoxic effect of the toxin by the influence of which excretion of tubular round epithelial cells is increased. The nephrotoxic effect of repeated administration of amphotericin B (1 mg/kg, i.v.), which produced up to 12-fold increases in the number of excreted epithelial cells, was examined. Repeated administration of cyclosporin A (45 and 56 mg/kg, p.o.) produced up to 23-fold increases in the number of excreted epithelial cells. The degree of excretion of epithelial cells after administration of both drugs was compared with the urinary excretion of alanine aminopeptidase and N-acetyl-beta-D-glucosaminidase, which indicated nephrotoxicity in amphotericin B and cyclosporin A with a lower sensitivity than the increase in the excretion of epithelial cells. In the experiment with cyclosporin A, urinary excretion of epithelial cells was further correlated with renal functional tests (clearance of polyfructosan and hippurate.

Effects of aflatoxin B1 on the sensitivity of the rat central nervous system to pentobarbital-Na racemate

The immobility time of pentobarbital was prolonged in male rats treated with aflatoxin B1 (AFB1), 2 mg/kg, with maximum on the 3rd day after treatment. It cannot be fully explained by the pharmacokinetic mechanisms. In parallel ED50 of pentobarbital was decreased both in males and females. In males the lethal dose of pentobarbital was decreased by about 30%. The pentobarbital concentration in the brain was increased during the immobility time and at awakening after the ip administration of 40 mg/kg of the drug on the 3rd day after AFB1 treatment with doses of 1 mg/kg and 2 mg/kg po in males and females, respectively. The plasma concentration of pentobarbital was significantly increased in treated males only. The content of unchanged pentobarbital in urine within 24 h after its administration was not high (about 1% in males, 2% in females) and in the AFB1 treated animals it virtually did not change. The elevation of the brain level of barbiturate at the time of awakening in AFB1 treated animals may point to a decreased sensitivity to pentobarbital.

Is DH-ergotoxine the best gerontologicum from the ergot source? Experimental comparison with individual components

The effect of DH-ET (dihydroergotoxine = 33% DH-ergocornine (DH-ECO) + 33% DH-ergocristine (DH-ECS) + + 33% DH-ergokryptine (DH-alfa-ECP: DH-beta-ECP = 2:1 and that of the single DH-derivatives on the retention of 14C-uridine (14C-U) in three parts of the brain tissue, blood plasma and liver tissue was estimated (i.e. radioactivity four hours after ip. adm. of 74kBq X 100 g-1). In young male rats DH-ET and DH-ECO enhanced the retention of 14C-U especially in the parietal cortex In one year old males DH-ECS and DH-alfa-ECP had the greatest effect. As a model of undesired effects the influence on peripheral blood flow in the hind limb of urethanised rats was examined using the perfusion' technics. All substances in the dose of 1 microgram removed epinephrine induced vasoconstriction although they themselves in the dose of 100 micrograms enhanced the perfusion pressure, excepting DH-ECO. All substances diminished the liver blood pool in urethanised rabbits (as norepinephrine does), most efficient being DH-beta-ECP and DH-ECO. On the other hand these substances also slowed the velocity of blood stream. The highest toxicity (LD) of DH-ECS and the lowest one of DH-alfa-ECP was found by an infusion technique. All substances diminished heart frequency but had a variable effect on PQ and QT ECG intervals. Ranging all substances according to their desirable properties from the geriatric viewpoint an index for each substance was calculated. This was most advantageous in the case of DH-alfa-ECP and DH-ECS in contrast to DH-ET and DH-ECO.

[Microlithiasis alveolaris pulmonum. (author's transl)]

A report was made of a long term observation of microlethiasis alveolaris pulmonum in a female patient who died at the age of 53. The rare, etiologically unclear disease is after a long course , always fatal due to right heart failure. This case was unique in that small spotty pulmonary lesions were found radiologically. They presented, a pathognomonic, unmistakable picture for a differential diagnosis of silicosis.

Sex differences in the fate of N-methyl-14C-pethidine in rats

N-Methyl-14C-labeled pethidine was administered intravenously to male and female rats at a dose of 1.25 mg per kg body weight. The amount of 14CO2 (originating from the N-methyl group) in the expired air of female rats was approximately a half of that expired by males. The amounts of radioactive metabolites (probably mainly deesterified products) in the excretions was higher in females. Pethidine levels in liver reach their maximum later, but attain substantially higher levels in females. The shapes of the curves relating pethidine levels to time are identical for blood and brain, but the brain levels are approximately ten times higher. Their course approximates a simple exponential curve in females, but a curve composed of two exponentials in males. Using the COMANSL computer programme and the data for blood levels, a three-compartment model has been established consisting of a central compartment 1, into which the drug was administered, a rapidly exchanging ("shallow") compartment 2, which is in equilibrium with 1, and a slowly exchanging ("deep") compartment 3, from which it is eliminated. Rate constants computed for the entry into and the exit from 1 were similar (0.23 and 0.22) in males; they could not be determined in females (possibly since they were too high). The passage from 1 to 3 was faster in males (0.07) than in females (0.04), the elimination from 3 was substantially faster in males (1.97) than in females (0.33). Faster demethylation in males is attributed to higher demethylation activity of male liver, known from in vitro experiments and faster rate of alternative pathways in females to higher substrate concentration in the liver. Attention is drawn to the considerable sex differences in the distribution of the drug.