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Dive into the research topics where Grzegorz Polak is active.

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Featured researches published by Grzegorz Polak.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2001

Total antioxidant status of peritoneal fluid in infertile women

Grzegorz Polak; Maria Kozioł-Montewka; Marek Gogacz; Iwona Błaszkowska; Jan Kotarski

OBJECTIVE To determine whether impairment of the antioxidant systems of peritoneal fluid might be a factor responsible for infertility. STUDY DESIGN Total antioxidant status was measured in peritoneal fluid obtained from 18 infertile women suffering from minimal or mild endometriosis, 23 patients with unexplained infertility, 12 women with tubal infertility and 13 fertile women. RESULTS Total antioxidant status was significantly lower in peritoneal fluid from women with unexplained infertility (0.49+/-0.21 mmol/l) compared to both fertile patients (0.67+/-0.24 mmol/l, P=0.02) and women with tubal infertility (0.76+/-0.26 mmol/l, P=0.001). Peritoneal fluid total antioxidant status did not differ significantly between patients with endometriosis (0.61+/-0.2 mmol/l), tubal infertility and the fertile group (P>0.05). CONCLUSIONS Our results suggest that low antioxidant status in peritoneal fluid may play a role in the pathogenesis of infertility.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2013

Increased levels of oxidative stress markers in the peritoneal fluid of women with endometriosis

Grzegorz Polak; Iwona Wertel; Bartłomiej Barczyński; Wojciech Kwaśniewski; Wiesława Bednarek; Jan Kotarski

OBJECTIVE To evaluate 8-hydroxy-2-deoxyguanosine (8-OHdG) and 8-isoprostane levels in the peritoneal fluid (PF) of women with endometriosis. STUDY DESIGN One hundred and ten women with laparoscopically and histopathologically confirmed endometriosis and, as reference groups, 119 patients with simple serous (n=78) and dermoid (n=41) ovarian cysts were studied. Peritoneal fluid 8-OHdG and 8-isoprostane concentrations were evaluated by enzyme-linked immunosorbent assays. RESULTS 8-OHdG and 8-isoprostane levels in peritoneal fluid were significantly higher in patients with endometriosis compared with the reference groups. Higher PF 8-OHdG and 8-isoprostane concentrations were observed in patients with advanced stages of endometriosis. A statistically significant positive correlation was found between 8-OHdG and 8-isoprostane levels in peritoneal fluid. CONCLUSION Endometriosis induces greater oxidative stress and frequent DNA mutations in peritoneal fluid than nonendometriotic ovarian cysts. The most severe oxidative stress occurs in the peritoneal cavity of women with more advanced stages of the disease.


International Reviews of Immunology | 2016

Tumor-Associated Macrophages and Myeloid-Derived Suppressor Cells as Immunosuppressive Mechanism in Ovarian Cancer Patients: Progress and Challenges

Karolina Okła; Iwona Wertel; Grzegorz Polak; Justyna Surówka; Anna Wawruszak; Jan Kotarski

Cancers are complex masses of malignant cells and nonmalignant cells that create the tumor microenvironment (TME). Non-transformed cells of the TME such as tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs) have been observed in the TME of ovarian cancer (OC) patients. Although these subsets may contribute to each step of carcinogenesis and are commonly associated with poor prognosis, still little is known about creation of the protumor microenvironment in OC. In this review, we focused on the nature and prognostic significance of TAMs and MDSCs in OC patients. Moreover, we discuss the main problems and challenges that must be overcome by researchers and clinicians to enrich our knowledge about the immunosuppressive microenvironment of cancers.


Mediators of Inflammation | 2013

Low-Density Lipoproteins Oxidation and Endometriosis

Grzegorz Polak; Bartłomiej Barczyński; Wojciech Kwaśniewski; Wiesława Bednarek; Iwona Wertel; Magdalena Derewianka-Polak; Jan Kotarski

The etiopathogenesis of endometriosis still remains unknown. Recent data provide new valuable information concerning the role of oxidative stress in the pathophysiology of the disease. It has been proved that levels of different lipid peroxidation end products are increased in both peritoneal fluid (PF) and serum of endometriotic patients. We assessed the concentration of oxidized low-density lipoproteins (oxLDL) in PF of 110 women with different stages of endometriosis and 119 women with serous (n = 78) or dermoid (n = 41) ovarian cysts, as the reference groups. PF oxLDL levels were evaluated by ELISA. We found that concentrations of oxLDL in PF of endometriotic women were significantly higher compared to women with serous but not dermoid ovarian cysts. Interestingly, by analyzing concentrations of oxLDL in women with different stages of the disease, it was noted that they are significantly higher only in the subgroup of patients with stage IV endometriosis as compared to women with ovarian serous cysts. In case of minimal, mild, and moderate disease, PF oxLDL levels were similar to those noted in reference groups. Our results indicate that disrupted oxidative status in the peritoneal cavity of women with endometriosis may play a role in the pathogenesis of advanced stages of the disease.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2003

Investigation of glutathione concentrations in peritoneal fluid from women with and without endometriosis

Grzegorz Polak; Iwona Wertel; Maria Kozioł-Montewka; Rafał Tarkowski; Jan Kotarski

UNLABELLED Changes in the peritoneal fluid (PF) environment have been implicated in the pathogenesis of endometriosis as well as in the decrease of fertility. OBJECTIVE To evaluate the concentration of glutathione in PF of women with endometriosis. PATIENTS Twenty-one patients with endometriosis (I or II rAFS stage, n=11; III or IV rAFS stage, n=10), and 29 patients with follicular or dermoid ovarian cysts (n=17 and n=12, respectively). RESULTS Mean (+/-S.D.) PF glutathione concentration was 0.22+/-0.01 micromol/ml in patients with minimal or mild endometriosis, 0.21+/-0.05 micromol/ml in women with III or IV stage of the disease, 0.24 +/- 0.03 micromol/ml in women with follicle ovarian cysts, and 0.23+/-0.05 micromol/ml in patients with dermoid tumors of ovaries. No significant difference in the peritoneal glutathione level was found between the groups. CONCLUSION These results suggest that PF glutathione is not involved in the progression of endometriosis.


Genes, Chromosomes and Cancer | 2016

Molecular bases of aberrant miR-182 expression in ovarian cancer.

Barbara Marzec-Kotarska; Marek Cybulski; Józef Kotarski; Anna Ronowicz; Rafał Tarkowski; Grzegorz Polak; Halina Antosz; Arkadiusz Piotrowski; Jan Kotarski

The molecular bases of miR‐182 deregulation in epithelial ovarian cancers (EOCs) remain unknown and its diagnostic or prognostic role in EOCs is still unclear. We performed miR‐182 expression analysis using a microarray approach and real‐time PCR (qPCR). We also used array comparative genomic hybridization and methylated DNA immunoprecipitation to study copy number changes and methylation aberrations within coding locus/promoter sequences of miR‐182 in EOC tissues, respectively. We have found that miR‐182 expression is significantly increased in EOC (P < 0.00001) and that higher miR‐182 expression in EOC is linked with significantly shorter overall survival (P = 0.026). The methylation of miR‐182 promoter was significantly associated with lower miR‐182 expression in EOC tissues (P = 0.045). miR‐182 over‐expression is connected with copy number (CN) gains of this miRNA coding sequences in EOC (P = 0.002), and the number of PRDM5 copies is significantly and inversely correlated with miR‐182 expression evaluated by qPCR (R = −0.615, P = 0.009). We conclude that the aberrant miR‐182 expression in EOC may be due to CN gains within its coding locus. The miR‐182 promoter is rarely methylated in EOC, and its methylation status is associated with lower miR‐182 expression. Deletion of the PRDM5 locus may play a supportive role in miR‐182 overexpression in EOC. miR‐182 is an unfavorable prognostic factor in EOC.


Ginekologia Polska | 2016

Anti-Müllerian hormone: structure, properties and appliance

Marzena Rzeszowska; Agnieszka Leszcz; Lechosław Putowski; Magdalena Hałabiś; Joanna Tkaczuk-Włach; Jan Kotarski; Grzegorz Polak

Anti-Müllerian hormone (AMH) is a glycoprotein produced by the granulosa cells of preantral and small antral follicles. AMH concentrations reflect ovarian physiology with high precision, thus serving as a more sensitive marker of the ovarian reserve than the chronological age. This hormone plays a role in the pathogenesis of menstrual disorders and fertility in obesity and polycystic ovary syndrome. The evaluation of AMH may also be useful in the diagnosis or the monitoring therapy of granulosa cells ovarian tumors.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2017

New variants near RHOJ and C2, HLA-DRA region and susceptibility to endometriosis in the Polish population—The genome-wide association study

Marta Sobalska-Kwapis; Beata Smolarz; Marcin Słomka; Tomasz Szaflik; Ewa Kępka; Bartosz Kulig; Anna Siewierska-Górska; Grzegorz Polak; Hanna Romanowicz; Dominik Strapagiel; Krzysztof Szyłło

OBJECTIVE Endometriosis is a common gynaecological disease, associated with severe pelvic pain and reduced fertility; however, molecular mechanisms remain largely unknown. Genome-wide association studies (GWAS) are able to identify genetic loci, which can play significant role during endometriosis development. AIM The study aimed at localisation of new genes and chromosomal loci, the nucleotide variants of which determine the level of susceptibility to endometriosis. STUDY DESIGN Blood samples from 171 patients with endometriosis were used as material for studies. The patients were recruited to the study at the Department of Operative Gynaecology of the Institute of the Polish Mothers Memorial Hospital in Lodz. A control group (n=2934) came from the POPULOUS collection registered at Biobank Lab, Department of Molecular Biophysics, University of Lodz. DNA of the patients with endometriosis was compared with DNA of women free from that disease, the comparison being supported by GWAS. RESULTS Genome-wide significant correlation was identified between one new, not previously described, single nucleotide polymorphism (SNP), rs10129516, localised on chromosome 14 in intergenic region between PARP1P2 and RHOJ genes (p=1.44×10-10, OR=3.104, 95% CI=2.329-4.136) and endometriosis. We have also identified significant association with endometriosis of 18 SNPs localised on chromosome 6 in position range 31883957 - 32681631 (C2 and HLA-DRA genes region) with the lowest observed p value for rs644045 in C2 gene (p=2.04×10-8, OR=1.955, 95% CI=1.541-2.480). CONCLUSION Reported GWAS identified the novel loci associated with endometriosis in Polish women, not previously reported. The most interesting observation shown in our study are regions associated with susceptibility to endometriosis of loci located near C2, HLA-DRA and RHOJ genes. RESULTS of that study did not correspond to previously published data about polymorphism in that regions and further evaluations are necessary in groups with higher numbers of patients to explain whether the above-mentioned genetic variant may be the risk factor for pathogenesis of endometriosis.


Ginekologia Polska | 2016

Anti-Müllerian hormone: a critical factor for female fertility and reproductive health.

Marzena Rzeszowska; Agnieszka Leszcz; Lechosław Putowski; Magdalena Hałabiś; Joanna Tkaczuk-Włach; Jan Kotarski; Grzegorz Polak

Anti-Müllerian hormone (AMH) is a glycoprotein produced by the granulosa cells of preantral and small antral follicles. AMH concentrations reflect ovarian physiology with high precision, thus serving as a more sensitive marker of the ovarian re-serve than chronological age. This hormone plays a role in the pathogenesis of menstrual disorders and fertility in both obesity and polycystic ovary syndrome. The evaluation of AMH may also be useful in diagnosing or monitoring therapy of granulosa cell ovarian tumors.


Molecular Medicine Reports | 2015

Analysis of cytosine-adenine repeats in P1 promoter region of IGF-1 gene in peripheral blood cells and cervical tissue samples of females with cervical intraepithelial lesions and squamous cervical cancer.

Wojciech Kwasniewski; Anna Gozdzicka-Jozefiak; Maria Kotarska; Grzegorz Polak; Bartłomiej Barczyński; Justyna Broniarczyk; Witold Nowak; Maria Wołuń-Cholewa; Anna Kwasniewska; Jan Kotarski

High oncogenic risk human papillomaviruses (HPVs) are closely associated with cancer of the cervix. However, HPV infection alone may not be sufficient to cause cervical cancer, and other factors or cofactors may have a cumulative effect on the risk of progression from cervical HPV infection to cancer. The present study investigates the cytosine-adenine (CA) repeat polymorphism in the P1 promoter region of the insulin-like growth factor-1 (IGF-1) gene among cervical precancerous and cancer patients and healthy control females. The association between these polymorphisms, tissue and blood serum levels of IGF-1, and cervical cancer risk and progression is evaluated. The material for analysis consisted of blood cells and postoperative tissues from patients diagnosed with low-grade squamous intraepithelial lesions (L-SILs), high-grade squamous intraepithelial lesions (H-SILs) and invasive cervical cancer (ICC). A polymerase chain reaction amplification and the sequencing of DNA were used for the identification of (CA)n repeats in the IGF-1 P1 region and detection of HPV DNA. The blood serum concentration of IGF was determined by enzyme-linked immunosorbent assay. The identification of the IGF-1 protein in the cervical tissues was performed by immunohistochemical analysis. The range of the length of the CA repeats in the study DNA was 11 to 21. However, the most common allele length and genotype in the control and study patients from serum and tissues was 19 CA repeats and a homozygous genotype of CA19/19. Statistically significant differences in the concentration of IGF-1 in the blood serum were observed between H-SILs and controls, only (p=0.047). However, the concentration of IGF-1 in the group of females with CA19/19, CA19<19 and CA19>19 was significantly higher in the group of patients with H-SIL (P=0.041) and ICC (P=0.048) in comparison with the control group. An association was detected between CA repeat length <19 and/or >19, IGF concentration in blood serum and tissues and the development of cervical cancer.

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Jan Kotarski

Medical University of Lublin

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Iwona Wertel

Medical University of Lublin

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Wiesława Bednarek

Medical University of Lublin

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Marcin Bobiński

Medical University of Lublin

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Karolina Okła

Medical University of Lublin

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Marek Gogacz

Medical University of Lublin

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Anna Gozdzicka-Jozefiak

Adam Mickiewicz University in Poznań

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