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Featured researches published by Zdenek Kala.


Carcinogenesis | 2014

HOTAIR long non-coding RNA is a negative prognostic factor not only in primary tumors, but also in the blood of colorectal cancer patients

Miroslav Svoboda; Jana Slyskova; Michaela Schneiderova; Peter Makovicky; Ludovit Bielik; Miroslav Levy; Ludmila Lipska; Beáta Hemmelová; Zdenek Kala; Markéta Protivánková; Ondrej Vycital; Vaclav Liska; Lucie Schwarzová; Ludmila Vodickova; Pavel Vodicka

Colorectal cancer (CRC) is one of the main causes of death of neoplasia. Demand for predictive and prognostic markers to reverse this trend is increasing. Long non-coding RNA HOTAIR (Homeobox Transcript Antisense Intergenic RNA) overexpression in tumors was previously associated with poor prognosis and higher mortality in different carcinomas. We analyzed HOTAIR expression levels in tumor and blood of incident sporadic CRC patients in relation to their overall survival with the aim to evaluate surrogate prognostic marker for CRC. Tissue donor group consisted of 73 CRC patients sampled for tumor and normal tissue. Blood donor group was represented by 84 CRC patients compared with 40 healthy controls. Patients were characterized for tumor-node-metastasis stage, tumor grade, microsatellite instability and tumor penetration by stromal cells. HOTAIR levels were assessed by real-time quantitative PCR. CRC patients had higher HOTAIR expression in blood than healthy controls (P = 0.0001), whereas there was no difference in HOTAIR levels between tumor and adjacent mucosa of CRC patients. HOTAIR levels positively correlated between blood and tumor (R = 0.43, P = 0.03). High HOTAIR levels in tumors were associated with higher mortality of patients [Coxs proportional hazard, hazard ratio = 4.4, 95% confidence interval: 1.0-19.2, P = 0.046]. The hazard ratio was even higher when blood HOTAIR levels were taken into account (hazard ratio = 5.9, 95% confidence interval: 1.3-26.1, P = 0.019). Upregulated HOTAIR relative expression in primary tumors and in blood of CRC patients is associated with unfavorable prognosis. Our data suggest that HOTAIR blood levels may serve as potential surrogate prognostic marker in sporadic CRC.


Pancreas | 2013

Differences in Transcript Levels of ABC Transporters Between Pancreatic Adenocarcinoma and Nonneoplastic Tissues

Beatrice Mohelnikova-Duchonova; Þ Veronika Brynychova; Martin Oliverius; Eva Honsova; Zdenek Kala; Katarina Muckova; Pavel Soucek

Objectives The aim of this study was to evaluate transcript levels of all 49 human ATP-binding cassette transporters (ABCs) in one of the most drug-resistant cancers, namely, the pancreatic ductal adenocarcinoma (PDAC). Association of ABCs levels with clinical-pathologic characteristics and KRAS mutation status was followed as well. Methods Tumors and adjacent nonneoplastic tissues were obtained from 32 histologically verified PDAC patients. The transcript profile of ABCs was assessed using quantitative real-time polymerase chain reaction with a relative standard curve. KRAS mutations in exon 2 were assessed by high-resolution melting analysis and sequencing. Results Most ABCs were deregulated in PDAC and 10 ABCs were associated with clinical-pathologic characteristics. KRAS mutations did not change the global expression profile of ABCs. Conclusions The expression of ABC transporters was significantly deregulated in PDAC tumors when compared to nonmalignant tissues. The observed up-regulation of ABCB4, ABCB11, ABCC1, ABCC3, ABCC5, ABCC10, and ABCG2 in tumors may contribute to the generally poor treatment response of PDAC. The up-regulation of ABCA1, ABCA7, and ABCG1 implicates a serious impairment of cellular cholesterol homeostasis in PDAC. On the other hand, the observed down-regulation of ABCA3, ABCC6, ABCC7, and ABCC8 suggests a possible role of stem cells in the development and progression of PDAC.


European Journal of Gastroenterology & Hepatology | 2008

Expression of COX-2 is associated with accumulation of p53 in pancreatic cancer: analysis of COX-2 and p53 expression in premalignant and malignant ductal pancreatic lesions.

Markéta Hermanová; Jan Trna; Rudolf Nenutil; Petr Dite; Zdenek Kala

Objectives Cyclooxygenase-2 (COX-2) and tumor suppressor p53 are molecules that are linked to the oncogenesis of pancreatic cancer. COX-2 represents a key modulatory molecule in inflammation and carcinogenesis, and is known to be implicated in the positive regulation of growth and tumorigenesis. Abnormal expression of p53 is common in many human neoplasms including pancreatic cancer. Recent studies demonstrated functional interactions between p53 and COX-2. The p53-dependent upregulation of COX-2 was proposed to be another mechanism by which p53 could abate its own growth-inhibitory and apoptotic effects. Methods In this study, we immunohistochemically analyzed the expression of COX-2 and p53 in 95 pancreatic resection specimens [adenocarcinomas, 95 lesions; pancreatic intraepithelial neoplasias (PanINs), 155; normal ducts, 70]. Results The expression of COX-2 increased progressively with the grade of ductal lesions (P<0.00001). A statistically significant difference of COX-2 expression between normal ducts and low-grade PanINs was revealed (P=0.0042). COX-2 overexpression was demonstrated in 82 PanINs (52.9%), and in 76 adenocarcinomas (80%). No significant correlation between the grade of adenocarcinoma and COX-2 expression was revealed (P=0.2). The expression of p53 again increased progressively with the grade of lesions (P<0.00001) with a significant increase in high-grade PanINs. A correlation between COX-2 and p53 expression levels in carcinomas was revealed (P=0.0002), and an accumulation of p53 was associated with COX-2 overexpression in premalignant and malignant ductal lesions. Conclusion These findings confirmed the generally accepted pancreatic cancer progression model, and supported the concept of the interactive role of COX-2 and p53 in pancreatic cancer carcinogenesis, which offers opportunities for targeted therapy and chemoprevention of pancreatic cancer using COX-2 inhibitors.


Carcinogenesis | 2016

Serum-based microRNA signatures in early diagnosis and prognosis prediction of colon cancer

Petra Vychytilova-Faltejskova; Lenka Radová; Milana Šachlová; Zdenka Kosarova; Katerina Slaba; Pavel Fabian; Tomáš Grolich; Vladimír Procházka; Zdenek Kala; Marek Svoboda; Igor Kiss; Rostislav Vyzula; Ondrej Slaby

Early detection of colorectal cancer is the main prerequisite for successful treatment and reduction of mortality. Circulating microRNAs were previously identified as promising diagnostic, prognostic and predictive biomarkers. The purpose of this study was to identify serum microRNAs enabling early diagnosis and prognosis prediction of colon cancer. In total, serum samples from 427 colon cancer patients and 276 healthy donors were included in three-phase biomarker study. Large-scale microRNA expression profiling was performed using Illumina small RNA sequencing. Diagnostic and prognostic potential of identified microRNAs was validated on independent training and validation sets of samples using RT-qPCR. Fifty-four microRNAs were found to be significantly deregulated in serum of colon cancer patients compared to healthy donors (P < 0.01). A diagnostic four-microRNA signature consisting of miR-23a-3p, miR-27a-3p, miR-142-5p and miR-376c-3p was established (AUC = 0.917), distinguishing colon cancer patients from healthy donors with sensitivity of 89% and specificity of 81% (AUC = 0.922). This panel of microRNAs exhibited high diagnostic performance also when analyzed separately in colon cancer patients in early stages of the disease (T1-4N0M0; AUC = 0.877). Further, a prognostic panel based on the expression of miR-23a-3p and miR-376c-3p independent of TNM stage was established (HR 2.30; 95% CI 1.44-3.66; P < 0.0004). In summary, highly sensitive signatures of circulating microRNAs enabling non-invasive early detection and prognosis prediction of colon cancer were identified.


Diagnostic Pathology | 2015

MiR-21, miR-34a, miR-198 and miR-217 as diagnostic and prognostic biomarkers for chronic pancreatitis and pancreatic ductal adenocarcinoma

Petra Vychytilova-Faltejskova; Igor Kiss; Sona Klusova; Jan Hlavsa; Vladimír Procházka; Zdenek Kala; Jan Mazanec; Jitka Hausnerová; Leos Kren; Markéta Hermanová; Jiri Lenz; Petr Karasek; Rostislav Vyzula; Ondrej Slaby

BackgroundPancreatic ductal adenocarcinoma is an aggressive malignancy with late presentation, metastatic potential and very poor prognosis. Therefore, there is an urgent need for novel diagnostic and prognostic biomarkers. MicroRNAs are small non-coding RNAs that post-transcriptionally regulate gene expression. Altered expression of microRNAs has been reported in wide range of malignancies, including pancreatic ductal adenocarcinoma. The aim of this study was to analyze the expression of selected microRNAs in normal pancreas, chronic pancreatitis and pancreatic ductal adenocarcinoma tissues and evaluate their diagnostic and prognostic potential.FindingsUsing quantitative real-time PCR, expression levels of 4 microRNAs were examined in 74 tumor tissues, 18 tissues of chronic pancreatitis and 9 adjacent normal tissues and correlated with clinicopathological features of patients. Expression levels of miR-21, miR-34a and miR-198 were significantly higher, whereas levels of miR-217 were significantly lower in pancreatic ductal adenocarcinomas compared to healthy tissues and tissues of chronic pancreatitis. Moreover, increased expression of miR-21 and miR-198 was significantly associated with shorter disease free survival and overall survival.ConclusionsOur data suggest that altered expression of examined microRNAs is related to neoplastic transformation and progression of the disease and these microRNAs could serve as diagnostic and prognostic biomarkers for pancreatic ductal adenocarcinoma.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1373952531543898


Cancer Chemotherapy and Pharmacology | 2013

The association between the expression of solute carrier transporters and the prognosis of pancreatic cancer

Beatrice Mohelnikova-Duchonova; Veronika Brynychova; Viktor Hlavac; Matej Kocik; Martin Oliverius; Jan Hlavsa; Eva Honsova; Jan Mazanec; Zdenek Kala; Bohuslav Melichar; Pavel Soucek

ObjectivesThe aim of this study was to investigate the prognostic significance of fourteen anticancer drug-relevant solute carrier transporters (SLCs) in pancreatic cancer in the context of clinical–pathological characteristics and the KRAS mutation status of tumors.MethodsTumors and non-neoplastic pancreatic tissues were obtained from 32 histologically verified patients with pancreatic ductal adenocarcinoma. The transcript profile of SLCs was assessed using quantitative real-time PCR. KRAS mutations in exon 2 were assessed by high-resolution melting analysis and confirmed by sequencing.ResultsSLC22A3 and SLC22A18 were upregulated and SLC22A1, SLC22A2, SLC22A11, SLC28A1, SLC28A3 and SLC29A1 were downregulated when compared with non-neoplastic pancreatic tissues. Moreover, significantly lower levels of SLC22A1, SLC22A11 and SLC29A1 were found in tumors with angioinvasion. There was also a significantly higher transcript level of SLC28A1 in tumors with regional lymph nodes affected by metastasis. The study found that a high expression of SLC28A1 was significantly associated with poor overall survival in unselected patients. In contrast, a high expression of SLC22A3 or SLC29A3 was significantly associated with longer overall survival in patients treated with nucleoside analogs. Protein expression of SLC22A1, SLC22A3 and SLC29A3 in tumor tissues of patients with pancreatic carcinoma was observed by immunoblotting for the first time. Finally, SLC levels were not found to be associated with KRAS mutation status in exon 2.ConclusionsThis study identified a number of associations of transcript levels of SLCs with prognosis of pancreatic cancer patients.


Human Immunology | 2013

Haplotypes of the IL-1 gene cluster are associated with gastroesophageal reflux disease and Barrett’s esophagus

Lydie Izakovičová Hollá; Petra Borilova Linhartova; Barbara Hrdličková; Filip Marek; Jiri Dolina; Vladimir Rihak; Zdenek Kala

OBJECTIVES Gastroesophageal reflux (GERD) is a one of the major public health problem that can lead to reflux esophagitis (RE), Barretts esophagus (BE), and esophageal adenocarcinoma (EAC). The aim of our study was to determine the impact of IL-1 gene polymorphisms on the development of GERD, RE and BE. METHODS Three hundred and thirty-three Czech patients with gastroesophageal reflux and 165 healthy controls were included in this case-control study. Four polymorphisms in the genes of the IL-1 cluster [IL-1A(-889C/T), IL-1B(-511C/T), IL-1B(+3953C/T), and IL-1RN(VNTR)] were analyzed. RESULTS Significant differences were found in IL-1RN 1/2 genotype between patients with GERD/RE and controls and in IL-1B+3953 T allele between patients with BE and healthy subjects. In addition, complex analysis revealed differences in IL-1 haplotype frequencies between the groups. Specifically, the haplotype TCCL was significantly more frequent (p = 0.016) in GERD patients than in controls and the haplotype CCCL more frequent (p = 0.008) in RE patients than in controls. However, in patients with BE, frequency of haplotype TCTL was lower (p = 0.05) and haplotypes CTCL and TCCL were higher (p = 0.03 and p = 0.02) in comparison with the controls. CONCLUSIONS Our results suggest that IL-1 haplotypes may be associated with susceptibility to GERD, RE and BE.


Acta Chirurgica Belgica | 2006

Laparoscopically assisted subtotal colectomy for idiopathic pneumatosis cystoides intestinalis

Zdenek Kala; Markéta Hermanová; Petr Kysela

Abstract Pneumatosis cystoides intestinalis (PCI) is a rare entity in which gas filled cysts are found within the intestinal wall. Conservative management and the treatment of underlying illnesses are recommended in most patients and surgery is usually indicated when acute and life-threatening complications such as bowel necrosis, perforation or peritonitis appear. The authors report a case of idiopathic pneumatosis cystoides intestinalis which, after repeated failure of conservative treatment including the oxygen therapy in hyperbaric chamber, was successfully treated by laparoscopic subtotal colectomy. A laparoscopically assisted approach proved to be a good indication in subtotal colectomy in cases of PCI that are non-responsive to standard conservative treatment.


Cancer Genomics & Proteomics | 2018

Pre-operative Plasma miR-21-5p Is a Sensitive Biomarker and Independent Prognostic Factor in Patients with Pancreatic Ductal Adenocarcinoma Undergoing Surgical Resection

Petr Karasek; Natalia Gablo; Jan Hlavsa; Igor Kiss; Petra Vychytilova-Faltejskova; Markéta Hermanová; Zdenek Kala; Ondrej Slaby; Vladimír Procházka

Blood plasma microRNAs (miRNAs) are emerging as a clinically useful tool for non-invasive detection and prognosis estimation in various cancer types including pancreatic ductal adenocarcinoma (PDAC). The aim of the present study was to provide an independent validation of circulating miRNAs identified in previous studies as diagnostic and/or prognostic biomarkers in PDAC. Based on the literature search, 6 miRNAs were chosen as candidates for independent validation; miR-21-5p, miR-375, miR-155, miR-17-5p, miR-126-5p and miR-1290. Validation of these miRNAs was performed in a cohort of 25 patients with PDAC undergoing surgical resection and 24 healthy donors. Plasma levels of miRNAs were determined using quantitative real-time PCR. We confirmed significantly higher levels of all tested miRNA in blood plasma of PDAC patients in comparison to healthy controls with miR-21-5p showing the highest analytical performance (p<0.001; AUC>0.99). Increased levels of miR-21-5p (p=0.045) and miR-375 (p=0.013) were significantly associated with overall survival. Multivariate analysis demonstrated that miR-21-5p is a significant unfavorable prognostic factor independent on other clinical variables including adjuvant chemotherapy (hazard ratio 2.95; 95% CI 1.06-8.18; p=0.038). Our preliminary data indicate promising diagnostic and prognostic utility of plasma miR-21-5p in PDAC patients.


Cancer Epidemiology and Prevention Biomarkers | 2018

Circulating PIWI-Interacting RNAs piR-5937 and piR-28876 Are Promising Diagnostic Biomarkers of Colon Cancer

Petra Vychytilova-Faltejskova; Karolína Štítkovcová; Lenka Radová; Milana Šachlová; Zdenka Kosarova; Katerina Slaba; Zdenek Kala; Marek Svoboda; Igor Kiss; Rostislav Vyzula; William C. Cho; Ondrej Slaby

Background: The early detection of colon cancer is one of the main prerequisites for successful treatment and mortality reduction. Circulating PIWI-interacting RNAs (piRNA) were recently identified as novel promising biomarkers. The purpose of the study was to assess the profiles of piRNAs in blood serum of colon cancer patients with the aim to identify those with high diagnostic potential. Methods: Blood serum samples from 403 colon cancer patients and 276 healthy donors were included in this 3-phase biomarker study. Large-scale piRNA expression profiling was performed using Illumina small RNA sequencing. The diagnostic potential of selected piRNAs was further validated on independent training and validation sets of samples using RT-qPCR. Results: In total, 31 piRNAs were found to be significantly deregulated in serum of cancer patients compared with healthy donors. Based on the levels of piR-5937 and piR-28876, it was possible to differentiate between cancer patients and healthy donors with high sensitivity and specificity. Moreover, both piRNAs exhibited satisfactory diagnostic performance also in patients with stage I disease and enabled detection of colon cancer with higher sensitivity than currently used biomarkers CEA and CA19-9. Finally, the expression of analyzed piRNAs in blood restored significantly 1 month after the surgical resection. Conclusions: Based on our findings, piRNAs are abundant in human blood serum. Furthermore, their levels in colon cancer have been observed to be significantly deregulated. However, their involvement in carcinogenesis must be further established. Impact: piRNAs could serve as promising noninvasive biomarkers for early detection of colon cancer. Cancer Epidemiol Biomarkers Prev; 27(9); 1019–28. ©2018 AACR.

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Eva Honsova

Charles University in Prague

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Pavel Soucek

Charles University in Prague

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