Browsing by Author "Ristanovic, Momcilo (56357953700)"

Purpose: To analyze if cell-free (cf)DNA levels and the presence of KRAS and BRAF mutations in serum could be used as diagnostic biomarkers in patients with primary colorectal cancer (CRC). Methods: This study included 92 individuals who were operated due to primary CRC (N=52;study group) and to hemorrhoids (N=40;control group). Serum cfDNA levels were measured with real-time PCR (RT-PCR) using PicoGreen dsDNA quantitation reagent. Colorectal tissue and related blood and serum samples taken at the time of surgery were subjected to DNA extraction and analysis of KRAS and BRAF mutations based on multiplex SNaPshot assay and DNA sequencing. Results: The average cfDNA concentration was lower in patients of the study group (20±7 ng/μL) in comparison to controls (34±9 ng/μL) and this difference was statistically significant (p<0.001). The SNaPshot analysis detected KRAS c35 mutations in colorectal tumor tissue in 14 cases, but the presence of the mutation was not confirmed in cfDNA extracted from blood samples of these patients. Conclusions: The level of serum cfDNA in CRC is decreased in comparison to patients with hemorrhoids, which questions the usefulness of cfDNA as cancer biomarker. Also, cfDNA does not appear to be suitable as a source for mutation detection in this disease.

Purpose: To analyze if cell-free (cf)DNA levels and the presence of KRAS and BRAF mutations in serum could be used as diagnostic biomarkers in patients with primary colorectal cancer (CRC). Methods: This study included 92 individuals who were operated due to primary CRC (N=52;study group) and to hemorrhoids (N=40;control group). Serum cfDNA levels were measured with real-time PCR (RT-PCR) using PicoGreen dsDNA quantitation reagent. Colorectal tissue and related blood and serum samples taken at the time of surgery were subjected to DNA extraction and analysis of KRAS and BRAF mutations based on multiplex SNaPshot assay and DNA sequencing. Results: The average cfDNA concentration was lower in patients of the study group (20±7 ng/μL) in comparison to controls (34±9 ng/μL) and this difference was statistically significant (p<0.001). The SNaPshot analysis detected KRAS c35 mutations in colorectal tumor tissue in 14 cases, but the presence of the mutation was not confirmed in cfDNA extracted from blood samples of these patients. Conclusions: The level of serum cfDNA in CRC is decreased in comparison to patients with hemorrhoids, which questions the usefulness of cfDNA as cancer biomarker. Also, cfDNA does not appear to be suitable as a source for mutation detection in this disease.

Objective: This study was aimed at analyzing alterations in K-ras gene and SMAD4 gene promoter in endometrial carcinoma tissue in Serbian patients. Methods/Materials: The study has encompassed 36 patients whose endometrial cancer tissue samples and peripheral blood samples were analyzed for the presence of alterations in the K-ras gene and the SMAD4 gene promoter. The detection of K-ras codon 12 mutation was performed by polymerase chain reaction restriction fragment length polymorphism technique. Analysis of mononucleotide repeat variants at -462T(15) and -4T(12) of the SMAD4 gene promoter was performed by capillary electrophoresis analysis of DNA fragments fluorescently labeled by polymerase chain reaction. Results: Mutation in codon 12 of the K-ras gene was detected with relatively high frequency of 75.0% (27 of 36 cases). Analysis of 2 mononucleotide repeats in the SMAD4 gene promoter showed that in most cases, haplotypes -462T(15)/-4T(12) and -462T(16)/-4T(12) were present; whereas in one case, a novel haplotype -462T(15)/-4T(10) was detected. Conclusions: Findings on the role and potential significance of the K-ras codon 12 mutation and SMAD4 gene promoter variants in patients with endometrial carcinoma remain controversial, and their occurrence in this type of cancer should be further investigated. Copyright © 2012 by IGCS and ESGO.

Purpose: In recent years, many genes have been associated with male infertility; however, testing of monogenic forms has not yet been clinically implemented in the diagnosis of severe forms of idiopathic male infertility, as the diagnostic utility has not been established yet. The aim of this study was therefore to answer if the implementation of genetic testing for monogenic forms of male infertility could contribute to the clinical diagnosis of men with severe forms of idiopathic male infertility. Materials and Methods: Based on the ClinGene curation protocol, we defined a panel of genes with sufficient evidence for the involvement with severe male infertility. We tested the 21-gene panel in a representative multicentric cohort of men with significantly impaired spermatogenesis. We performed whole exome sequencing on 191 infertile men with severe forms of idiopathic male infertility; non-obstructive azoospermia, and severe oligozoospermia (<5 million spermatozoa/mL). The control group consisted of 216 men who fathered a child. DNA was prepared based on the Twist CORE exome protocol and sequenced on the Illumina NovaSeq 6000 platform. Variants were classified using the Association for Clinical Genomic Science (ACGS) Best Practice Guidelines for Variant Classification in Rare Disease 2020. Results: We identified potential monogenic disease-causing variants in four infertile men. Pathogenic/likely pathogenic variants in STAG3 (c.2776C>T, p.Arg926*; c.2817delG, p.Leu940fs), MSH4 (c.1392delG, p.Ile465fs; c.2261C>T, p.Ser754Leu), TEX15 (c.6848_6849delGA, p.Arg2283fs; c.6271dupA, p.Arg2091fs), and TEX14 (c.1021C>T, p.Arg341*) genes were found. Conclusions: In the present multicentric cohort study, a monogenic cause in 2.1% of infertile men was identified. These findings confirm the utility of monogenic testing and suggest the clinical use of monogenic testing for men with severe forms of idiopathic male infertility. Copyright © 2025 Korean Society for Sexual Medicine and Andrology.

Purpose: In recent years, many genes have been associated with male infertility; however, testing of monogenic forms has not yet been clinically implemented in the diagnosis of severe forms of idiopathic male infertility, as the diagnostic utility has not been established yet. The aim of this study was therefore to answer if the implementation of genetic testing for monogenic forms of male infertility could contribute to the clinical diagnosis of men with severe forms of idiopathic male infertility. Materials and Methods: Based on the ClinGene curation protocol, we defined a panel of genes with sufficient evidence for the involvement with severe male infertility. We tested the 21-gene panel in a representative multicentric cohort of men with significantly impaired spermatogenesis. We performed whole exome sequencing on 191 infertile men with severe forms of idiopathic male infertility; non-obstructive azoospermia, and severe oligozoospermia (<5 million spermatozoa/mL). The control group consisted of 216 men who fathered a child. DNA was prepared based on the Twist CORE exome protocol and sequenced on the Illumina NovaSeq 6000 platform. Variants were classified using the Association for Clinical Genomic Science (ACGS) Best Practice Guidelines for Variant Classification in Rare Disease 2020. Results: We identified potential monogenic disease-causing variants in four infertile men. Pathogenic/likely pathogenic variants in STAG3 (c.2776C>T, p.Arg926*; c.2817delG, p.Leu940fs), MSH4 (c.1392delG, p.Ile465fs; c.2261C>T, p.Ser754Leu), TEX15 (c.6848_6849delGA, p.Arg2283fs; c.6271dupA, p.Arg2091fs), and TEX14 (c.1021C>T, p.Arg341*) genes were found. Conclusions: In the present multicentric cohort study, a monogenic cause in 2.1% of infertile men was identified. These findings confirm the utility of monogenic testing and suggest the clinical use of monogenic testing for men with severe forms of idiopathic male infertility. Copyright © 2025 Korean Society for Sexual Medicine and Andrology.

Introduction: Numerous parameters can affect the quality of life (QL) during pregnancy. Goal: The aim of the study was to evaluate QL in healthy pregnant women. Methods: Study involved every sixth woman who gave birth in Clinic of Gynecology and Obstetrics Clinical Center of Serbia, Belgrade, during the year 2010. They filled in the SF-36 questionnaire, Beck's Depression Inventory (BDI), Fatigue Severity Scale (FSS), Pregnancy Symptom Scale (PSS), Multidimensional Personal Support Scale (MSPSS) and Acceptance of Illness Scale (AIS). Results: There were 604 women included in the study. Mean scores of the scales were: total SF-36-70.7, BDI-3.8, FSS-3.5, PSS-2.1, MSPSS- 70.3, AIS-14.0. The values of total QL, PSS and MSPSS scores were highly significantly correlated with all other examined scale scores. BDI and FSS were not correlated only with MSPSS. Significant models of correlation were obtained for SF-36 scores: total QL (R=0.597; adjR2=0.351; F=66.281; p=0.000). Conclusion: The QL during pregnancy was good. Examined women did not have significant levels of depression, fatigue and symptoms during pregnancy. Women had good social support and tolerated pregnancy well. However, depression, fatigue, pregnancy tolerance and social support can all significantly affect the quality of life during pregnancy. Most attention should be directed to pregnancy-related depression and fatigue.

Purpose: The purpose of this study was to investigate into the expression of cyclin A and telomerase in renal cell carcinoma (RCC) and to analyze the relationship between expression and the clinicopathological characteristics of the tumor and their impact on survival. Methods: The overall material included 74 samples of RCC and 4 of normal renal tissue. Primary cyclin A antibody from Santa Cruz Biotechnology and TERT MA5-16034 antibody from Thermo Fisher Scientific Inc were used. Staining was performed by streptavidin-biotin technique using DAKO LSAB+ kit. Statistical analyses were performed using of SPSS 23 Statistics software from IBM. Results: No differences in cyclin A and telomerase expression among gender and age groups were found, nor did the tumor dimensions have any significant impact on expression. Also, tumor grades and stages did not differ. However, histological types differed in favor of the papillary type. A significant positive correlation between both markers, as well as between the expression and tumor stage and grade was noticed. Only the tumor stage had negative impact on survival. Conclusions: Although not affecting survival, the expression of cyclin A and telomerase increased with tumor stage and grade, suggesting that cyclin A and telomerase could be potential proliferative immunohistochemical markers of RCC. © 2018 Zerbinis Publications. All Rights Reserved.

Purpose: The purpose of this study was to investigate into the expression of cyclin A and telomerase in renal cell carcinoma (RCC) and to analyze the relationship between expression and the clinicopathological characteristics of the tumor and their impact on survival. Methods: The overall material included 74 samples of RCC and 4 of normal renal tissue. Primary cyclin A antibody from Santa Cruz Biotechnology and TERT MA5-16034 antibody from Thermo Fisher Scientific Inc were used. Staining was performed by streptavidin-biotin technique using DAKO LSAB+ kit. Statistical analyses were performed using of SPSS 23 Statistics software from IBM. Results: No differences in cyclin A and telomerase expression among gender and age groups were found, nor did the tumor dimensions have any significant impact on expression. Also, tumor grades and stages did not differ. However, histological types differed in favor of the papillary type. A significant positive correlation between both markers, as well as between the expression and tumor stage and grade was noticed. Only the tumor stage had negative impact on survival. Conclusions: Although not affecting survival, the expression of cyclin A and telomerase increased with tumor stage and grade, suggesting that cyclin A and telomerase could be potential proliferative immunohistochemical markers of RCC. © 2018 Zerbinis Publications. All Rights Reserved.

Introduction: It is well known that numerous habits can affect the quality of life. Goal: The aim of the study was to assess the influence of different lifestyle habits of pregnant women on their quality of life during pregnancy. Methods: Study involved every sixth women who gave birth in our Clinic during the year 2010. They filled in SF36 questionnaire, Beck's Depres-sion Inventory, Fatigue Severity Scale, Pregnancy Symptom Scale, Multidimensional Personal Sup-port Scale and Acceptance of Illness Scale. Infor-mation regarding habits such as smoking, drink-ing alcohol and doing sports and recreation were taken from all women. Results: Study included 604 respondents. The correlation between smoking duration and depres-sion was positive and significant (p=0.042). Depres-sion and fatigue were significantly higher (p=0.002; p=0.008) in women who drank alcohol during pregnancy. Social support was significantly better for women who did sports (p=0.044). Depression (p=0.001), social support (p=0.001) and all SF36 scores (pPHC=0.028; pMHC=0.017; pTQL=0.013) were significantly higher in women doing recreation dur-ing pregnancy. A significant model of impact on physical health, of all habits together, was made: PHC=62.039+1.732xSMOKING DURATION. Conclusion: Pregnant women should continue with physical activities during pregnancy but quit smoking and drinking in order to ensure healthy pregnancy and good quality of life during preg-nancy.

Purpose: The RAD51 gene plays an important role in homologous strand exchange in DNA repair. Two common single nucleotide polymorphisms in this gene, 135G>C and 172G>T, were associated with altered gene transcription. While 135G>C was already linked to breast and colorectal cancers in certain populations, 172G>T is far less investigated, although sporadic studies showed it could be a prognostic factor for some cancer lesions. The purpose of this study was to investigate RAD51 172G>T polymorphism in Serbian population, its association with colorectal carcinoma, as well as correlation with disease characteristics and response to neoadjuvant chemoradiotherapy. Methods: The 172G>T polymorphism was evaluated by PCR-RFLP method in blood samples of 209 colorectal cancer patients and 43 healthy subjects who served as controls. The distribution of genotypes was also analyzed in respect to several tumor characteristics in cases where histopathological data were available. Results: A significant association between the RAD51 172G>T polymoprhism and desmoplastic reaction of colorectal cancer was demonstrated. The 172G allele was found to be significantly more frequent in patients with more intensive desmoplastic response of the tumor tissue. Conclusions: The results of our study suggest that the 172T allele of RAD51 may be a favorable prognostic factor in Serbian patients with colorectal cancer, although larger prospective studies are required to confirm this finding. © 2018 Zerbinis Publications. All Rights Reserved.

Purpose: The RAD51 gene plays an important role in homologous strand exchange in DNA repair. Two common single nucleotide polymorphisms in this gene, 135G>C and 172G>T, were associated with altered gene transcription. While 135G>C was already linked to breast and colorectal cancers in certain populations, 172G>T is far less investigated, although sporadic studies showed it could be a prognostic factor for some cancer lesions. The purpose of this study was to investigate RAD51 172G>T polymorphism in Serbian population, its association with colorectal carcinoma, as well as correlation with disease characteristics and response to neoadjuvant chemoradiotherapy. Methods: The 172G>T polymorphism was evaluated by PCR-RFLP method in blood samples of 209 colorectal cancer patients and 43 healthy subjects who served as controls. The distribution of genotypes was also analyzed in respect to several tumor characteristics in cases where histopathological data were available. Results: A significant association between the RAD51 172G>T polymoprhism and desmoplastic reaction of colorectal cancer was demonstrated. The 172G allele was found to be significantly more frequent in patients with more intensive desmoplastic response of the tumor tissue. Conclusions: The results of our study suggest that the 172T allele of RAD51 may be a favorable prognostic factor in Serbian patients with colorectal cancer, although larger prospective studies are required to confirm this finding. © 2018 Zerbinis Publications. All Rights Reserved.

Aim: The aim of this study was to determine the prevalence and type of microdeletions of the Y chromosome of men with severe oligozoospermia-ICSI candidates in the Serbian population and to compare our findings with those from other parts of the world. Methods: In all patients spermiogram has been performed in order to determine the sperm concentration. Patients were subjected to detailed clinical, endocrinological and cytogenetic examinations. Microdeletion analysis was performed by polymerase chain reaction (PCR) on 203 patients with normal cytogenetic findings. The STS markers tested in each case were sY84, sY86 (AZFa); SY127, sY134 (AZFb); sY254, sY255 (AZFc). Results: at least one of the STS markers was deleted in 11 of the 203 cases (5.4 %). Conclusion: AZFc microdeletions were identified with a rather high prevalence in men with severe oligozoospermia ICSI candidates in Serbian population.

As a key component of the transforming growth factor beta (TGFB) pathway, which regulates the expression of thyroid-specific genes, tumor suppressor SMAD4 is crucial for thyroid development and function. Aberrant expression of SMAD4 in thyroid tumor tissue was reported and mutations affecting the coding region have been detected, but a potential role of mutations in SMAD4 gene regulatory regions remains unexplored. The aim of this study was to analyze SMAD4 gene promoters in thyroid tumors. A total of 76 thyroidectomy specimens were studied, including 42 malignant and 34 benign tumors. The presence of mutations in four SMAD4 gene promoters was analyzed in thyroid tumor tissue and peripheral blood by PCR and DNA sequencing. The expression and intracellular localization of endogenous SMAD4 protein in selected tumor samples was studied by immunostaining and confocal microscopy. Of three novel variants detected, two were within promoter A (-. 204T/C and. 5C/T) and one in promoter D (-. 180delA). Unlike somatic mutations previously detected in the nearby region, germline mutation. 180delA in promoter D doesn't appear to affect SMAD4 expression in the thyroid tumor tissue. However, all newly detected SMAD4 promoter variants affect predicted binding sites of transcription factors involved in cell cycle regulation and should be further characterized functionally. Although not directly involved in carcinogenesis, detected variants may alter SMAD4 transcriptional regulation to some extent. Considering that dosage dependence is of great importance for the role of SMAD4 protein as a tumor suppressor, potential clinical significance of SMAD4 gene promoter mutations is worth further investigation. © 2015 Elsevier Inc.

As a key component of the transforming growth factor beta (TGFB) pathway, which regulates the expression of thyroid-specific genes, tumor suppressor SMAD4 is crucial for thyroid development and function. Aberrant expression of SMAD4 in thyroid tumor tissue was reported and mutations affecting the coding region have been detected, but a potential role of mutations in SMAD4 gene regulatory regions remains unexplored. The aim of this study was to analyze SMAD4 gene promoters in thyroid tumors. A total of 76 thyroidectomy specimens were studied, including 42 malignant and 34 benign tumors. The presence of mutations in four SMAD4 gene promoters was analyzed in thyroid tumor tissue and peripheral blood by PCR and DNA sequencing. The expression and intracellular localization of endogenous SMAD4 protein in selected tumor samples was studied by immunostaining and confocal microscopy. Of three novel variants detected, two were within promoter A (-. 204T/C and. 5C/T) and one in promoter D (-. 180delA). Unlike somatic mutations previously detected in the nearby region, germline mutation. 180delA in promoter D doesn't appear to affect SMAD4 expression in the thyroid tumor tissue. However, all newly detected SMAD4 promoter variants affect predicted binding sites of transcription factors involved in cell cycle regulation and should be further characterized functionally. Although not directly involved in carcinogenesis, detected variants may alter SMAD4 transcriptional regulation to some extent. Considering that dosage dependence is of great importance for the role of SMAD4 protein as a tumor suppressor, potential clinical significance of SMAD4 gene promoter mutations is worth further investigation. © 2015 Elsevier Inc.

Background: The tumor suppressor gene SMAD4 (DPC4) encodes for the common intracellular mediator of the TGF-β superfamily pathway, which regulates numerous cellular processes, such as cell proliferation, cell differentiation, apoptosis, cell fate and migration. This study was aimed to investigate the presence of genetic variants in SMAD4 gene promoter in malignant pancreatic and colorectal tissue and to analyze their functional consequences. Methods: The study was performed on genomic DNA isolated from malignant tissue samples obtained on surgery from 50 patients with pancreatic carcinoma and 50 patients with colorectal cancer. Screening for mutations within an 800. bp-long fragment of the SMAD4 gene promoter was performed by DNA sequencing and two mononucleotide repeats, at positions -462 and -4, were found to be polymorphic in malignant tissue. The exact number of thymidines in the tracts -462T(15) and -4T(12) was determined by PCR with fluorescently labeled primers followed by capillary electrophoresis. Functional analysis of -462T(15)/-4T(12) haplotypes was performed by luciferase reporter assays. Results: Haplotype -462T(14)/-4T(10) was found in 85% of pancreatic cancer tissues, but it was not present in any of colorectal cancer tissues. Statistically significant reduction (p< 0.001) in activity was observed in the haplotype -462T(14)/-4T(10) in comparison with the haplotypes -462T(15)/-4T(12) and -462T(14)/-4T(11). Conclusion: Results of this study indicate that novel genetic variant -4T(10) in the SMAD4 gene promoter affects its activity and that element -4T(12) may play a role in transcriptional regulation of SMAD4 gene expression. Obtained results, though preliminary, also indicate that SMAD4 gene promoter haplotype -462T(14)/-4T(10) may represent a genetic marker of potential relevance for pancreatic and colorectal cancer. The findings of this study should be confirmed by further investigation in these two and other tumors, on larger number of patients and with different tumor stages. Translational research aimed at investigating potential application of mononucleotide repeats -462T(15) and -4T(12) in SMAD4 gene promoter as molecular markers in cancer may also prove useful. © 2010 Elsevier Ltd.

Background: The tumor suppressor gene SMAD4 (DPC4) encodes for the common intracellular mediator of the TGF-β superfamily pathway, which regulates numerous cellular processes, such as cell proliferation, cell differentiation, apoptosis, cell fate and migration. This study was aimed to investigate the presence of genetic variants in SMAD4 gene promoter in malignant pancreatic and colorectal tissue and to analyze their functional consequences. Methods: The study was performed on genomic DNA isolated from malignant tissue samples obtained on surgery from 50 patients with pancreatic carcinoma and 50 patients with colorectal cancer. Screening for mutations within an 800. bp-long fragment of the SMAD4 gene promoter was performed by DNA sequencing and two mononucleotide repeats, at positions -462 and -4, were found to be polymorphic in malignant tissue. The exact number of thymidines in the tracts -462T(15) and -4T(12) was determined by PCR with fluorescently labeled primers followed by capillary electrophoresis. Functional analysis of -462T(15)/-4T(12) haplotypes was performed by luciferase reporter assays. Results: Haplotype -462T(14)/-4T(10) was found in 85% of pancreatic cancer tissues, but it was not present in any of colorectal cancer tissues. Statistically significant reduction (p< 0.001) in activity was observed in the haplotype -462T(14)/-4T(10) in comparison with the haplotypes -462T(15)/-4T(12) and -462T(14)/-4T(11). Conclusion: Results of this study indicate that novel genetic variant -4T(10) in the SMAD4 gene promoter affects its activity and that element -4T(12) may play a role in transcriptional regulation of SMAD4 gene expression. Obtained results, though preliminary, also indicate that SMAD4 gene promoter haplotype -462T(14)/-4T(10) may represent a genetic marker of potential relevance for pancreatic and colorectal cancer. The findings of this study should be confirmed by further investigation in these two and other tumors, on larger number of patients and with different tumor stages. Translational research aimed at investigating potential application of mononucleotide repeats -462T(15) and -4T(12) in SMAD4 gene promoter as molecular markers in cancer may also prove useful. © 2010 Elsevier Ltd.