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Featured researches published by Paweł Knapp.


Prostaglandins & Other Lipid Mediators | 2010

Altered sphingolipid metabolism in human endometrial cancer

Paweł Knapp; Marcin Baranowski; Małgorzata Knapp; Piotr Zabielski; Agnieszka Blachnio-Zabielska; Jan Górski

There is a growing body of evidence indicating that bioactive sphingolipids play a key role in cancer development, progression and metastasis. However, sphingolipid metabolism in malignant tumors is poorly investigated. Therefore, the aim of the present study was to examine the content of selected intermediates of ceramide metabolism and the activity of key enzymes of ceramide de novo synthesis and sphingosine-1-phosphate (S1P) production in the endometrial cancer. The specimens of cancer tissue and healthy endometrium were obtained from women undergoing surgery because of the cancer (n=23) and because of myomas (n=18), respectively. The content of sphinganine, dihydroceramide, ceramide, sphingosine and S1P was measured using high pressure liquid chromatography. The activity of the enzymes was determined using radioactive substrates. It has been found that the content of each examined sphingolipid was markedly elevated in the cancer tissue compared with the healthy endometrium. Namely, sphinganine, sphingosine and dihydroceramide by 3-4.6-fold, ceramide and S1P by 1.9- and 1.6-fold, respectively. Interestingly, the ratio of S1P to ceramide remained stable. The activity of serine palmitoyltransferase and sphingosine kinase 1 was increased by 2.3- and 2.6-fold, respectively. We conclude that endometrial carcinoma is characterized by profound changes in sphingolipid metabolism that likely contribute to its progression and chemoresistance.


Advances in Medical Sciences | 2013

Expression of Estrogen Receptors (α, β), Cyclooxygenase-2 and Aromatase in normal endometrium and endometrioid cancer of uterus

Paweł Knapp; Adrian Chabowski; Agnieszka Blachnio-Zabielska; Malgorzata Walentowicz-Sadlecka; Marek Grabiec; Pa Knapp

PURPOSE Endometrial cancer (EC) is one of the most common malignancies of the female genital tract, but the etiology, especially its metabolism is still investigated. The aim of this study was to evaluate the presence and relative expression of Estrogen Receptors (α, β), Cyclooxygenase-2 and Aromatase in both endometrial cancer and normal mucosa. MATERIAL/METHODS Two groups of women were selected for the study: 1) patients with endometrioid endometrial cancer (FIGO I; G1 - G3) (n=35) and 2) subjects with normal endometrial tissue (control group, n=29). The expression of Estrogen Receptors (ERα, β), Cyclooxygenase-2 (COX-2), Aromatase were estimated by Western blot analysis. Furthermore, the associations between FIGO classification (stage: Ia, Ib), tumor grade (G) and expression of ERα, β, COX-2, aromatase proteins were evaluated. Overall and disease-free survival curves were generated according to the Kaplan-Meier method. Median follow-up time of the patients examined in this study was 39 months. RESULTS The relative expression of each examined protein was markedly higher in the endometrial cancer tissue as compared to the healthy endometrium. The trends towards greater expression along with a tumor progression was noticed (FIGO stage: Ia vs. Ib). Analysis of endometrial cancer risk factors and their influence on survival curves showed only an inverse significant correlations between obesity (BMI: 36.2; n=21) and disease-free survival in EC group (p=0.00872), but there was no significant association between obesity and overall survival (p=0.358). CONCLUSIONS Endometrioid endometrial cancer shows relatively higher expression of either ER, COX-2 and aromatase comparing to healthy mucosa, suggesting their involvement in tumor development and progression.


Ppar Research | 2012

Altered peroxisome-proliferator activated receptors expression in human endometrial cancer.

Paweł Knapp; Adrian Chabowski; Agnieszka Blachnio-Zabielska; Katarzyna Jarząbek; Slawomir Wolczynski

Peroxisome proliferator-activated receptors (PPARs) belong to a family of nuclear hormone receptors acting as transcriptional factors, recently involved also in carcinogenesis. Present study was undertaken to evaluate the presence and subcellular localization of different PPAR isoforms (α, β, γ) in healthy endometrial tissue (n = 10) and endometrial carcinoma (FIGO I, endometrioides type, G1, n = 35). We sought to analyze PPARs mRNA content as well as protein immunohistochemical expression that was further quantified by Western Blot technique. For both PPARα and PPARβ, protein expression was significantly higher in endometrial cancers compared to normal endometrial mucosa. In opposite, PPARγ protein expression was lower in endometrial cancer cells. In each case, immunohistochemical reaction was confined to the perinuclear and/or nuclear region. At the transcriptional level, the content of mRNA of all PPAR subunits did not follow the protein pattern of changes. These results provide evidence for altered PPARs protein expression and disregulation of posttranslational processes in endometrial cancers.


Advances in Medical Sciences | 2013

Dose-dependent effect of aspirin on the level of sphingolipids in human blood

Małgorzata Knapp; Anna Lisowska; Paweł Knapp; Marcin Baranowski

PURPOSE Aspirin is an antiplatelet drug which is commonly used in secondary prevention in ischemic heart disease and cerebrovascular events, and in newly diagnosed myocardial infarction. The aim of the present study was to examine effect of aspirin on the level of selected sphingolipid intermediates in plasma, erythrocytes and platelets. MATERIAL AND METHOD Forty two healthy volunteers participated in the study. They were divided into two groups. In one group aspirin was given orally, daily, for one week in a dose of 75 mg (n=25). The subjects from the second group received one 300 mg dose of the drug (n=17). In both groups the blood was taken 4h after the last dose of aspirin. The following sphingolipid intermediates were quantified using high-pressure liquid chromatography: sphinganine, sphingosine, sphingosine-1-phosphate (S1P), sphinganine-1-phosphate (SA1P) and ceramide. RESULTS It was found that lower dose of aspirin increased the level of S1P and ceramide in erythrocytes (by 23 and 37%, respectively) having no effect on plasma and platelet sphingolipid levels. Higher dose of the drug reduced S1P and SA1P concentration in the plasma (by 16 and 10%, respectively). CONCLUSION We conclude that aspirin interferes with sphingolipid metabolism in blood and that this effect depends on a dose of the drug. Since S1P is a potent cardioprotectant, the reduction in its plasma concentration after the loading dose of aspirin could be undesired side effect of the drug.


Hormone and Metabolic Research | 2012

Reversed Glucose and Fatty Acids Transporter Expression in Human Endometrial Cancer

Paweł Knapp; Adrian Chabowski; Dorota Harasiuk; Jan Górski

Cancer cells exhibit accelerated rates of metabolism favoring glucose over fatty acid (FA) utilization. For both energy substrates, protein-mediated transport plays an essential role in facilitating glucose or FA movement across plasma membrane into the cells. Scarce data exist regarding the expression of glucose and/or FA transporter in cancer tissue. Therefore, we examined glucose (GLUT-1, GLUT-3, GLUT-4) and FA (FAT/CD36, FABPpm, FATP-1) transporter expressions at the protein and post-transcript (mRNA) levels in 35 endometrial carcinomas (G1, type endometrioid, FIGO I) and compared them with normal endometrial mucosa (n=10). Endometrial cancer tissue had significantly greater protein expression of GLUT-1, GLUT-3, and GLUT-4 (+ 40%; + 20%; + 24%; p<0.05, respectively) and, conversely, lower fatty acid (FAT/CD36 and FATP-1) transporter expression ( - 25%; p<0.05 and - 15%, p>0.05 respectively). Interestingly, mRNA content closely mirrors the changes, but only for glucose transporters and not fatty acid transporters. These results suggest the presence of metabolic switch of energy utilization in endometrial cancers favoring glucose consumption as the major source of energy.


Folia Histochemica Et Cytobiologica | 2012

Pretreatment plasma levels and diagnostic utility of hematopoietic cytokines in cervical cancer or cervical intraepithelial neoplasia patients

Sławomir Ławicki; Grażyna Ewa Będkowska; Ewa Gacuta-Szumarska; Paweł Knapp; Maciej Szmitkowski

In this study, we compared plasma levels and the diagnostic utility of hematopoietic growth factors (HGFs) with SCC-Ag in cervical cancer patients in relation to control groups and cervical intraepithelial neoplasia (CIN) patients and healthy subjects. Pretreatment plasma levels of HGFs (SCF, GM-CSF, G-CSF and M-CSF) were determined by the use of immunoenzyme assay (ELISA), and SCC-Ag by chemiluminescent microparticle immunoassay (CMIA). Significantly different concentrations of GM-CSF, G-CSF and M-CSF were observed in the group of patients with cervical cancer and CIN compared to the healthy controls. Significant differences in plasma levels of GM-CSF and M-CSF between cervical cancer and benign lesions patients were also found. The HGFs and SCC-Ag diagnostic specificities received high values. The diagnostic sensitivity and the predictive value of a positive and negative test result were higher for M-CSF than for antigen SCC in the cancer group. The M-CSF area under the ROC curve (AUC) was the largest from hematopoietic cytokines and SCC-Ag. These results suggest the potential utility of M-CSF as a good candidate for a marker of cervical cancer as well as benign lesions of this organ (CIN).


Gynecologic Oncology | 2017

Plasma and ovarian tissue sphingolipids profiling in patients with advanced ovarian cancer

Paweł Knapp; Lubomir Bodnar; Agnieszka Blachnio-Zabielska; Magdalena Świderska; Adrian Chabowski

PURPOSE The role of lipids in carcinogenesis through induction of abnormal cell lines in the human body is currently undisputable. Based on the literature, bioactive sphingolipids play an essential role in the development and progression of cancer and are involved in the metastatic process. The aim of this study was to determine the concentration of selected sphingolipids in patients with advanced ovarian cancer (AOC, FIGO III/IV, high grade ovarian cancer). METHODS Seventy-four patients with ovarian cancer were enrolled. Plasma concentrations of C16-Cer, C18:1-Cer and C18-Cer were assessed by LC/MS/MS. The content of tissue sphingolipids was measured using a UHPLC/MS/MS. RESULTS Plasma concentration of 3 ceramides: C16-Cer, C18:1-Cer and C18-Cer was significantly elevated in women with advanced ovarian cancer compared to control group (P=0.031; 0.022; 0.020; respectively). There were increases in concentration of 5 ceramides: C16-Cer, C18:1-Cer, C18-Cer, C24:1-Cer, C24-Cer (P=0.025; 0.049; 0.032; 0.005; 0.013, respectively) and S1P (P=0.004) in ovarian tissue of women with advanced ovarian cancer compared to healthy individuals. Importantly, significantly higher risk of ovarian cancer when the plasma concentration of C16-Cer>311.88ng/100μl (AUC: 0.76, P=0.0261); C18:1-Cer>4.75ng/100μl (AUC: 0.77, P=0.0160) and C18-Cer>100.76ng/100μl (AUC:0.77, P=0.0136) was noticed. CONCLUSIONS Bioactive sphingolipids play an essential role in the development and progression of cancer and they also take part in the process of metastasizing. This study suggests that some sphingolipids can be used as potential biomarkers of advanced ovarian cancer and that they can play an important role in the pathogenesis of this disease.


Prostaglandins & Other Lipid Mediators | 2016

Expression of the energy substrate transporters in uterine fibroids.

Paweł Knapp; Adrian Chabowski; Renata Posmyk; Jan Górski

Proliferating cells exhibit accelerated rates of substrate utilization, favoring glucose over fatty acids (FAs) oxidation. Protein-mediated transport is thought to play a predominant role in facilitating either glucose or FA routing into the cells. In the present study, we examined the expression of glucose transporters (GLUT-1, GLUT-4) and fatty acids transporters (FAT/CD36, FATP-1, FATP-4) at transcript and protein levels as well as cytosolic fatty acid binding proteins (H-FABP, ACBP) in human fibroids (n=74, size up to 3cm diameter) and compared with pair-matched healthy myometrium. Additionally lipid content (diacylglycerols, triacylglycerols and ceramide) was estimated by gas liquid chromatography (GLC). Uterine fibroids displayed decreased expression of both FAT/CD36 and FATP-1 proteins along with lower diacylglycerol (DAG) and triacylglycerol (TAG) content as compared to healthy pair-matched myometrium. The expression of glucose transport proteins (GLUT-4 and GLUT-1) remained relatively constant, although the higher expression of GLUT-1 in uterine fibroids did not reach the minimum significance threshold (p=0.056). However, no change in either cytochrome c oxidase (COX IV) or hydroxyacyl-CoA dehydrogenase (HADHSC) was observed and these data confirm a possible metabolic shift favoring glucose utilization over fatty acid oxidation in human uterine fibroids.


Archives of Medical Science | 2018

Blood bioactive sphingolipids in patients with advanced serous epithelial ovarian cancer – mass spectrometry analysis

Paweł Knapp; Lubomir Bodnar; Agnieszka Blachnio-Zabielska; Joanna Reszeć; Magdalena Świderska; Adrian Chabowski

Introduction Due to the lack of highly specific and sensitive methods for diagnosing ovarian cancer at advanced stages (according to the International Federation of Gynecology and Obstetrics (FIGO) classification stage III–IV), new noninvasive biomarkers are urgently needed. This study aims to investigate how the levels of plasma bioactive sphingolipids (ceramides, sphingosine-1-phosphate, sphingosine and sphinganine) are altered in serum, erythrocytes and platelets of patients with advanced serous ovarian cancer. Material and methods A total of 135 patients with advanced serous ovarian cancer and 159 women with normal ovarian morphology were enrolled. Plasma levels of sphingosine, sphingosine-1-phosphate, sphinganine, ceramide C14:0-Cer, C16:0-Cer, C18:1-Cer, C18:0-Cer, C20:0-Cer, C22:0-Cer, C24:1-Cer and C24:0-Cer were assessed by LC/MS/MS. Results Plasma concentrations of C16-Cer, C18:1-Cer and C18-Cer were significantly higher in the advanced ovarian cancer group than in the control group (1.5-fold, p = 0.021; 1.8-fold, p = 0.036 and 1.5-fold, p = 0.031, respectively). Plasma concentration of C18:1-Cer was significantly higher in erythrocytes of women with advanced serous cancer compared to the control group (p = 0.027). Plasma C16-Cer and C18:1-Cer levels and erythrocyte C18:1-Cer levels were able to distinguish patients with moderate/severe serous ovarian cancer from patients with mild ovarian cancer (AUC: 0.86, 0.898, 0.795, respectively). Plasma concentrations of C16, C18.1 and C18 significantly correlated with FIGO staging (p = 0.001, p = 0.024 and p = 0.005), and grading (p = 0.021, p = 0.021 and p = 0.033). Conclusions Plasma concentrations of C16, C18.1 and C18 correlated with the progression of ovarian cancer (FIGO staging and grading). Plasma levels of C16-Cer and C18:1-Cer and erythrocyte C18:1-Cer levels could be used to distinguish patients with advanced serous ovarian cancer.


Current Gynecologic Oncology | 2017

Recommendations of the Polish Gynecological Oncology Society for the diagnosis andtreatment of endometrial cancer

Antoni Basta; Mariusz Bidziński; Andrzej Bieńkiewicz; Paweł Blecharz; Lubomir Bodnar; Robert Jach; Paweł Knapp; Zbigniew Kojs; Jan Kotarski; Janina Markowska; Marcin Misiek; Jacek J. Sznurkowski; Łukasz Wicherek; Włodzimierz Sawicki; Agnieszka Timorek-Lemieszczuk; Jan Bahyrycz; Radosław Mądry

© Medical Communications Sp. z o.o. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (CC BY-NC-ND). Reproduction is permitted for personal, educational, non-commercial use, provided that the original article is in whole, unmodified, and properly cited. Zalecenia Polskiego Towarzystwa Ginekologii Onkologicznej dotyczące diagnostyki i leczenia raka szyjki macicy Recommendations of the Polish Gynecological Oncology Society for the diagnosis and treatment of cervical cancer

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Adrian Chabowski

Medical University of Białystok

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Janina Markowska

Poznan University of Medical Sciences

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Robert Jach

Jagiellonian University Medical College

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Antoni Basta

Jagiellonian University

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Jan Kotarski

Medical University of Lublin

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Włodzimierz Sawicki

Medical University of Warsaw

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Łukasz Wicherek

Nicolaus Copernicus University in Toruń

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