Browsing by Author "Prvanovic, Mirjana (57201654195)"

Purpose: Renal cell carcinoma (RCC) is the most common renal cancer in adults and includes several subtypes that may be distinguished by their histology, genetic background, clinical course and responses to treatment. Human telomerase reverse transcriptase (hTERT), a crucial enzyme for telomere maintenance, has been linked to RCC development. The purpose of this study was to search for genetic and epigenetic alterations in hTERT (promoter mutations and methylation and gene amplification), and to establish a possible association between molecular and clinico-pathological characteristics of RCC. Methods: DNA was extracted from 31 formalin-fixed, paraffin-embedded tumor samples and 23 blood samples from 54 patients with RCC. Polymerase chain reaction (PCR) products were sequenced and analyzed using the Sequencher software. HTERT amplification was determined by quantitative PCR, while the promoter methylation status was assessed by methylation specific PCR. Statistical analysis was performed using SPSS. Results: No mutations could be detected in the hTERT promoter but only a single nucleotide polymorphism (SNP) (-245 T>C). In 54 analyzed RCC cases, the variant allele C was present in homozygous or heterozygous form in 48% of the patients. The C allele was significantly more frequent in low grade tumors (p=0.046). Gene amplification was detected in 19.4% of the 31 RCCs and hTERT methylation in 54.8% of the 31 samples. An association was established between methylation and histological type of RCC (p=0.047). Conclusions: HTERT seems to be implicated in RCC pathogenesis since the promoter polymorphism exerts a modulation effect on tumor behavior. In addition, hTERT promoter methylation status is related to RCC histology. © 2018 Zerbinis Publications. All Rights Reserved.

Purpose: Renal cell carcinoma (RCC) is the most common renal cancer in adults and includes several subtypes that may be distinguished by their histology, genetic background, clinical course and responses to treatment. Human telomerase reverse transcriptase (hTERT), a crucial enzyme for telomere maintenance, has been linked to RCC development. The purpose of this study was to search for genetic and epigenetic alterations in hTERT (promoter mutations and methylation and gene amplification), and to establish a possible association between molecular and clinico-pathological characteristics of RCC. Methods: DNA was extracted from 31 formalin-fixed, paraffin-embedded tumor samples and 23 blood samples from 54 patients with RCC. Polymerase chain reaction (PCR) products were sequenced and analyzed using the Sequencher software. HTERT amplification was determined by quantitative PCR, while the promoter methylation status was assessed by methylation specific PCR. Statistical analysis was performed using SPSS. Results: No mutations could be detected in the hTERT promoter but only a single nucleotide polymorphism (SNP) (-245 T>C). In 54 analyzed RCC cases, the variant allele C was present in homozygous or heterozygous form in 48% of the patients. The C allele was significantly more frequent in low grade tumors (p=0.046). Gene amplification was detected in 19.4% of the 31 RCCs and hTERT methylation in 54.8% of the 31 samples. An association was established between methylation and histological type of RCC (p=0.047). Conclusions: HTERT seems to be implicated in RCC pathogenesis since the promoter polymorphism exerts a modulation effect on tumor behavior. In addition, hTERT promoter methylation status is related to RCC histology. © 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.

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: Renal cell carcinoma (RCC) is the most common malignant kidney tumor in adults. Dysregulation of the cell cycle can lead to cancer development. In this study, the mitosis-associated cyclin A and p16, a negative controller, were investigated as potential key points in the RCC development. Methods: This retrospective study included 74 patients with RCC. The expression of cyclin A and p16 and their correlation to histopathological parameters (TNM stage, histological subtype, nuclear grade, tumor size), gender, age, and clinical outcome were studied and analyzed. Results: The highest median value for cyclin A (40%; range 0-70)) and for p16 (57.5%; range 35-80) were found in the papillary histological subtype. Survival analysis showed that in the group of patients that had died before September 2015, the median value for cyclin A was 20% (range 0-60), which was significantly higher than 5% (range 0-70), found in the group of patients that survived (p=0.019). Conclusions: In relation to the histological subtype, the papillary type of RCC was associated with a significantly higher expression of cyclin A and p16 compared to other subtypes of RCC. High expression of cyclin A indicated worse prognosis, therefore cyclin A could be considered to be a significant prognostic marker. © 2017 Zerbinis Publications. All rights reserved.

Purpose: Renal cell carcinoma (RCC) is the most common malignant kidney tumor in adults. Dysregulation of the cell cycle can lead to cancer development. In this study, the mitosis-associated cyclin A and p16, a negative controller, were investigated as potential key points in the RCC development. Methods: This retrospective study included 74 patients with RCC. The expression of cyclin A and p16 and their correlation to histopathological parameters (TNM stage, histological subtype, nuclear grade, tumor size), gender, age, and clinical outcome were studied and analyzed. Results: The highest median value for cyclin A (40%; range 0-70)) and for p16 (57.5%; range 35-80) were found in the papillary histological subtype. Survival analysis showed that in the group of patients that had died before September 2015, the median value for cyclin A was 20% (range 0-60), which was significantly higher than 5% (range 0-70), found in the group of patients that survived (p=0.019). Conclusions: In relation to the histological subtype, the papillary type of RCC was associated with a significantly higher expression of cyclin A and p16 compared to other subtypes of RCC. High expression of cyclin A indicated worse prognosis, therefore cyclin A could be considered to be a significant prognostic marker. © 2017 Zerbinis Publications. All rights reserved.