Jiri Heracek
Charles University in Prague
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Featured researches published by Jiri Heracek.
The New England Journal of Medicine | 2009
Matthew R. Smith; Blair Egerdie; Narciso Hernández Toriz; Robert G. Feldman; Teuvo L.J. Tammela; Fred Saad; Jiri Heracek; Maciej Szwedowski; Chunlei Ke; Amy Kupic; Benjamin Z. Leder; Carsten Goessl
BACKGROUND Androgen-deprivation therapy is well-established for treating prostate cancer but is associated with bone loss and an increased risk of fracture. We investigated the effects of denosumab, a fully human monoclonal antibody against receptor activator of nuclear factor-kappaB ligand, on bone mineral density and fractures in men receiving androgen-deprivation therapy for nonmetastatic prostate cancer. METHODS In this double-blind, multicenter study, we randomly assigned patients to receive denosumab at a dose of 60 mg subcutaneously every 6 months or placebo (734 patients in each group). The primary end point was percent change in bone mineral density at the lumbar spine at 24 months. Key secondary end points included percent change in bone mineral densities at the femoral neck and total hip at 24 months and at all three sites at 36 months, as well as incidence of new vertebral fractures. RESULTS At 24 months, bone mineral density of the lumbar spine had increased by 5.6% in the denosumab group as compared with a loss of 1.0% in the placebo group (P<0.001); significant differences between the two groups were seen at as early as 1 month and sustained through 36 months. Denosumab therapy was also associated with significant increases in bone mineral density at the total hip, femoral neck, and distal third of the radius at all time points. Patients who received denosumab had a decreased incidence of new vertebral fractures at 36 months (1.5%, vs. 3.9% with placebo) (relative risk, 0.38; 95% confidence interval, 0.19 to 0.78; P=0.006). Rates of adverse events were similar between the two groups. CONCLUSIONS Denosumab was associated with increased bone mineral density at all sites and a reduction in the incidence of new vertebral fractures among men receiving androgen-deprivation therapy for nonmetastatic prostate cancer. (ClinicalTrials.gov number, NCT00089674.)
Steroids | 2007
Jiri Heracek; Hampl Richard; Hill Martin; Starka Luboslav; Sachova Jana; Kuncova Jitka; Eis Vaclav; Urban Michael; Mandys Vaclav
Androgens are considered to play a substantial role in pathogenesis of both benign prostatic hyperplasia (BPH) and prostate cancer. The importance of determination of androgen levels in tissue and serum for cancer progression and prognosis has been poorly understood. The aim of study was to find out hormonal differences in both diseases, their correlations between intraprostatic and serum levels and predicted value of their investigation. Testosterone, dihydrotestosterone, androstenedione and also epitestosterone were determined in prostate tissue from 57 patients who underwent transvesical prostatectomy for BPH and 121 patients after radical prostatectomy for prostate cancer. In 75 subjects with cancer and 51 with BPH the serum samples were analyzed for testosterone, dihydrotestosterone and SHBG. Significantly higher intraprostatic androgen concentrations, i.e. 8.85+/-6.77 versus 6.44+/-6.43 pmol/g, p<0.01 for dihydrotestosterone, and 4.61+/-7.02 versus 3.44+/-4.53 pmol/g, p<0.05 for testosterone, respectively, were found in patients with prostate cancer than in BPH. Higher levels in cancer tissue were found also for epitestosterone. However, no differences were found in serum levels. Highly significant correlations occurred between all pairs of intraprostatic androgens and also epitestosterone as well as between serum testosterone and dihydrotestosterone (p<0.001) in both BPH and cancer groups. Correlation was not found between corresponding tissue and serum testosterone and dihydrotestosterone, either in benign or cancer samples. The results point to importance of intraprostatic hormone levels for evaluation of androgen status of patients, contrasting to a low value of serum hormone measurement.
Lancet Oncology | 2014
Bertrand Tombal; Michael Borre; Per Rathenborg; Patrick Werbrouck; Hendrik Van Poppel; Axel Heidenreich; Peter Iversen; Johan Braeckman; Jiri Heracek; Edwina Baskin-Bey; Taoufi k Ouatas; Frank Perabo; De Phung; Mohammad Hirmand; Matthew R. Smith
BACKGROUND The androgen receptor inhibitor enzalutamide is approved for the treatment of metastatic castration-resistant prostate cancer that has progressed on docetaxel. Our aim was to assess the activity and safety of enzalutamide monotherapy in men with hormone-naive prostate cancer. METHODS This trial is an ongoing open-label, single-arm, phase 2 study, done across 12 European sites. Men aged over 18 years, with hormone-naive prostate cancer for whom hormone therapy was indicated, and who had non-castration levels of testosterone and prostate-specific antigen (PSA) of 2 ng/mL or greater at screening, and an Eastern Cooperative Oncology Group score of 0, received oral enzalutamide 160 mg/day. The primary outcome was the proportion of patients with an 80% or greater decline in PSA at week 25. All analyses included all patients who had received at least one dose of the study drug. This study is registered with ClinicalTrials.gov, number NCT01302041. FINDINGS 67 men were enrolled into the study. 62 patients (92.5%, 95% CI 86.2-98.8) had a decline in PSA of 80% or greater at week 25. The most commonly reported treatment-emergent adverse events up to week 25 were gynaecomastia (n=24), fatigue (n=23), nipple pain (n=13), and hot flush (n=12), all of which were of mild to moderate severity. Nine patients had a treatment-emergent adverse event of grade 3 or higher, most of which were reported in one patient each, except for pneumonia (grade 3, two patients) and hypertension (grade 3, four patients). Five patients reported serious adverse events, none of which were deemed to be treatment related. INTERPRETATION Our findings suggest that enzalutamide monotherapy in men with hormone-naive prostate cancer of varying severity provides a level of disease suppression, and was generally well tolerated. These findings provide a rationale for further investigation of clinical response and outcomes with enzalutamide in non-castrate men with prostate cancer.
Talanta | 2015
Jana Vitku; Tereza Chlupacova; Lucie Sosvorova; Richard Hampl; Martin Hill; Jiri Heracek; Marie Bičíková; Luboslav Stárka
Bisphenol A (BPA) is a widely known endocrine disruptor with estrogenic, antiestrogenic or antiandrogenic properties. BPA could interfere with estrogen metabolism as well with receptor-mediated estrogen actions. Both environmental BPA and estrogens may be traced in body fluids, of which, besides the blood plasma, the seminal fluid is of particular interest regarding their possible interactions in the testis. The method for simultaneously determining BPA and estrogens is then needed, taking into account that their concentrations in these body fluid may differ. Here the method was developed and validated for measurements of BPA, estrone (E1), estradiol (E2) and estriol (E3) in blood plasma and seminal plasma using liquid chromatography-tandem mass spectrometry. Due to the phenolic moiety of all compounds, dansyl chloride derivatization could be used. The analytical criteria of the method with respect to expected concentration of the analytes were satisfactory. The lower limits of quantifications (LLOQ) amounted to 43.5, 4.0, 12.7, 6.7 pg/mL for plasma BPA, E1, E2 and E3, and 28.9, 4.9, 4.5, 3.4 pg/mL for seminal BPA, E1, E2 and E3, respectively. The concentrations of individual steroids differed between body fluids. To the best of our knowledge, this is the first method that enabled the measurement of estrogens and BPA together in one run. The concentrations of E1, E2 and for the first time also of E3 in seminal plasma in normospermic men are reported.
Urologia Internationalis | 2003
Roman Zachoval; Jiri Pitha; Eva Medová; Jiri Heracek; Martin Lukeš; Miroslav Zalesky; M. Urban
Introduction: Augmentation cystoplasty is an effective approach to the detrusor hyperreflexia which is refractory to conservative treatment. Sporadic data have been published in patients with progressive diseases such as multiple sclerosis (MS). Materials and Methods: Augmentation ileocystoplasty (Goodwin ‘cup-patch’) was performed in 9 patients (7 females, 2 males). The average Expanded Disability Status Scale score was 4.1 (range 3.0–6.5); 7 patients had relapse-remitting MS and 2 patients secondary-progressive MS. The indication was a detrusor hyperreflexia refractory to conservative treatment in 8 patients and a detrusor hyperrefluxia with third degree bilateral vesico-ureteral reflux and renal insufficiency in 1 patient. Pre- and postoperative objective parameters were evaluated by urodynamic examination, imaging methods and laboratory examination. Subjective evaluation was performed using a questionnaire on micturition symptoms (score 0–5) and on quality of life (score 0–6). Results: With a follow-up of 6–19 months, we recorded an average increase of the maximum detrusor capacity from 105 to 797 ml and decrease of maximum detrusor pressure from 53 to 30 cm H2O. Postmicturition residual urine >25% of the maximum capacity was present in 6 patients who performed clear intermittent autocatheterization postoperatively (2 patients preoperatively). In all patients there was a significant improvement in the irritation micturition symptomatology (pollakisuria, nycturia, urgency and urge incontinence) and the quality of life score improved on average from 5 to 0.7. In the case of the patient with renal insufficiency, the creatinine level decreased from 286 to 150 µmol/l; in the other patients renal function remained normal. Conclusions: Augmentation cystoplasty is a safe and effective method for indicated patients, which significantly enhances their quality of life.
The Journal of Steroid Biochemistry and Molecular Biology | 2016
Jana Vitku; Luboslav Stárka; Marie Bičíková; Martin Hill; Jiri Heracek; Lucie Sosvorova; Richard Hampl
Numerous chemicals in the environment have the ability to interact with the endocrine system. These compounds are called endocrine disruptors (EDs). Exposure to EDs represents one of the hypotheses for decreasing fertility, the increased risk of numerous cancers and obesity, metabolic syndrome and type 2 diabetes. There are various mechanisms of ED action, one of which is their interference in the action of 11β-hydroxysteroid dehydrogenase (11βHSD) that maintains a balance between active and inactive glucocorticoids on the intracellular level. This enzyme has two isoforms and is expressed in various tissues. Inhibition of 11βHSD in various tissues can have different consequences. In the case of EDs, the results of exposure are mainly adverse; on the other hand pharmaceutically developed inhibitors of 11βHSD type 1 are evaluated as an option for treating metabolic syndrome, as well as related diseases and depressive disorders. This review focuses on the effects of 11βHSD inhibitors in the testis, colon, adipose tissue, kidney, brain and placenta.
Human Reproduction | 2012
Miluse Vozdova; Jiri Heracek; Vladimír Sobotka; Jiri Rubes
BACKGROUND Non-obstructive azoospermic (NOA) men can father children after testicular sperm extraction (TESE). Previous studies suggest that they may be at risk of producing chromosomally abnormal spermatozoa, but the number of sperm analysed per patient was usually very low. METHODS Multicolour fluorescence in situ hybridization was used for detection of chromosome 13, 15, 16, 18, 21, 22, X and Y disomy and diploidy in sperm obtained from NOA men (n = 17) and control donors (n = 10). At least 500 testicular sperm were scored in each patient to increase the precision of our study. RESULTS The mean frequency of overall disomy (2.32%) and diploidy (0.80%) found in 13 689 testicular spermatozoa of NOA patients was significantly higher than in the ejaculated sperm of normospermic control donors, disomy (0.62%) and diploidy (0.29%). A highly significant increase in frequencies of chromosome 15, Y and overall disomy (P < 0.001), and a significant increase in disomy of chromosome 13 (P = 0.002), 16 (P = 0.031) and 21 (P = 0.018), overall diploidy (P = 0.031) and diploidy caused by errors in meiosis I (P = 0.011) were observed in the NOA group. CONCLUSIONS Testicular sperm samples of NOA patients show a higher incidence of numerical chromosomal abnormalities compared with ejaculated sperm of control donors. Appropriate genetic counselling is necessary in NOA men undergoing TESE.
International Journal of Urology | 2008
Miroslav Zalesky; M. Urban; Zdenek Šmerhovský; Roman Zachoval; Martin Lukeš; Jiri Heracek
Aim: The aim of the study is to investigate the value of preoperative power Doppler sonography with 3D reconstruction (3D‐PDS) for diagnostics of extraprostatic extension of prostate cancer.
Journal of Medical Virology | 2012
Ruth Tachezy; Jan Hrbacek; Jiri Heracek; Martina Salakova; Jana Smahelova; Viera Ludvíková; Svec A; M. Urban; Eva Hamsikova
HPV has carcinogenic effects at several anatomical sites in women and men. Whether the presence of HPV in the genitourinary tract of men is associated with a higher prostate cancer risk has been a matter of research for a long‐time and the results are still not fully conclusive. Similarly, the question of the reservoir of HPV infection in men is not clearly resolved. HPV DNA presence and types were evaluated by means of polymerase chain reaction in the tissue of 146 patients with benign prostate hyperplasia and prostate cancer. HPV‐specific antibodies were analyzed by enzyme‐linked immunosorbent assay in the sera of all patients and 172 controls. In addition, 256 biopsies taken from non‐tumorous tissues were analyzed. No statistically significant differences were observed in HPV DNA prevalence between patients with benign prostate hyperplasia (2%) and patients with prostatic cancer (2%; P = 1.000). The seropositivity rates did not differ significantly between groups of subjects except for antibodies against HPV 6 VLPs which were found more often in prostate cancer patients (adjusted P = 0.018). Similarly, no difference in the seroprevalence rates for HPV 16 E6 and/or E7 oncoproteins between groups of patients and healthy controls was detected. The overall HPV prevalence in 256 healthy tissue samples was 4%. The results indicate that HPV infection is not associated with prostate oncogenesis in men. However, they imply that multiple tissues of the male genitourinary tract may be important reservoirs for the transmission of some HPV types. J. Med. Virol. 84:1636–1645, 2012.
European Urology | 2015
Bertrand Tombal; Michael Borre; Per Rathenborg; Patrick Werbrouck; Hendrik Van Poppel; Axel Heidenreich; Peter Iversen; Johan Braeckman; Jiri Heracek; Edwina Baskin-Bey; Taoufik Ouatas; Frank Perabo; De Phung; Benoit Baron; Mohammad Hirmand; Matthew R. Smith
BACKGROUND Enzalutamide is an androgen receptor inhibitor with a demonstrated overall survival benefit in metastatic castration-resistant prostate cancer. A phase 2 study of enzalutamide monotherapy in patients with hormone-naïve prostate cancer (HNPC) showed a high response rate for the prespecified primary endpoint (ie, prostate-specific antigen [PSA] response at week 25), regardless of metastases at baseline, and favorable tolerability. OBJECTIVE To determine the long-term efficacy and safety of enzalutamide monotherapy at 1 and 2 yr. DESIGN, SETTING, AND PARTICIPANTS Open-label, single-arm study in patients with HNPC and noncastrate testosterone (≥230 ng/dl). INTERVENTION Oral enzalutamide 160mg/d until disease progression or unacceptable toxicity. OUTCOME MEASUREMENTS AND ANALYSIS PSA response (≥80% decline from baseline) assessed at 1 yr (49 wk) and 2 yr (97 wk). RESULTS AND LIMITATIONS The median (range) age was 73 (48-86) yr and 26 patients (39%) presented with metastases at study entry. Of 67 patients enrolled, 45 (67%) remained on enzalutamide at week 97. For patients remaining on therapy, the PSA response rate at week 97 was 100% (95% confidence interval 92-100%). Of 26 patients with metastases at baseline, 13 (50%) had a complete and four (15.4%) had a partial response as best overall tumor response up to 97 wk on treatment. There was overall maintenance of total-body bone mineral density (BMD) and moderate changes in lean and fat body mass at 49 and 97 wk. The most common adverse events were gynecomastia, nipple pain, fatigue, and hot flushes. The study limitations include lack of a control group and of endocrine, glycemic, and lipid data at 97 wk. CONCLUSIONS Long-term enzalutamide monotherapy in men with noncastrate HNPC is associated with large sustained reductions in PSA, signals indicating a favorable tumor response, and favorable safety/tolerability profile, with relatively small negative effects on total-body BMD. PATIENT SUMMARY In this long-term follow-up of the efficacy and safety of enzalutamide monotherapy in patients with hormone-naïve prostate cancer, enzalutamide maintained long-term reductions in prostate-specific antigen, with a minimal impact on total-body bone mineral density. TRIAL REGISTRATION NCT01302041.