Browsing by Author "Markovic, Srdjan (57210721043)"

[No abstract available]

Recent innovations in molecular biology and colorectal cancer (CRC) genetics have facilitated the understanding of the pathogenesis of sporadic and hereditary CRC syndromes. The development of technology has enabled data collection for a number of genetic factors, which lead to understanding of the molecular mechanisms underlying CRC. The incidence and the nature of CRC is a mixture of genetic and environmental factors. The current field of interest is to understand how molecular basis could shape predisposition for developing CRC, disease progression and response to chemotherapy. In this article, we summarize new and developing genetic markers, and assess their clinical value for inherited and sporadic CRC.

Recent innovations in molecular biology and colorectal cancer (CRC) genetics have facilitated the understanding of the pathogenesis of sporadic and hereditary CRC syndromes. The development of technology has enabled data collection for a number of genetic factors, which lead to understanding of the molecular mechanisms underlying CRC. The incidence and the nature of CRC is a mixture of genetic and environmental factors. The current field of interest is to understand how molecular basis could shape predisposition for developing CRC, disease progression and response to chemotherapy. In this article, we summarize new and developing genetic markers, and assess their clinical value for inherited and sporadic CRC.

Aim: To investigate mononucleotide markers: BAT-25, BAT-26, NR-21, NR-22 and NR-24 in patients with colorectal cancer (CRC), and the status of HSP110T17, KRAS, BRAF and the MLH1 promoter mutations in microsatellite unstable CRC. Methods: Genetic assessments were performed on samples obtained following resection of CRC in 200 patients. Results: Allelic variations of HSP110T17 were found in all 18 patients with microsatellite instabilities (MSIs) in at least three markers (high-frequency MSI). By contrast, mutations of HSP110T17 were absent in all 20 patients with no MSI frequency. Eight out of 182 patients with low (instability in one marker) or no frequency MSI had allelic shifts due to polymorphisms of BAT-25 (1.5%), NR-21 (1.75%) and NR-24 (1.5%). BRAF mutations were associated with >5 bp shortening of HSP110T17. Conclusion: Patients with high-frequency MSI CRC had allelic variations of HSP110T17. BRAF mutations occur along with greater shortening in HSP110T17 during oncogenesis via the MSI pathway. © 2013 Future Medicine Ltd.

Aim: To investigate mononucleotide markers: BAT-25, BAT-26, NR-21, NR-22 and NR-24 in patients with colorectal cancer (CRC), and the status of HSP110T17, KRAS, BRAF and the MLH1 promoter mutations in microsatellite unstable CRC. Methods: Genetic assessments were performed on samples obtained following resection of CRC in 200 patients. Results: Allelic variations of HSP110T17 were found in all 18 patients with microsatellite instabilities (MSIs) in at least three markers (high-frequency MSI). By contrast, mutations of HSP110T17 were absent in all 20 patients with no MSI frequency. Eight out of 182 patients with low (instability in one marker) or no frequency MSI had allelic shifts due to polymorphisms of BAT-25 (1.5%), NR-21 (1.75%) and NR-24 (1.5%). BRAF mutations were associated with >5 bp shortening of HSP110T17. Conclusion: Patients with high-frequency MSI CRC had allelic variations of HSP110T17. BRAF mutations occur along with greater shortening in HSP110T17 during oncogenesis via the MSI pathway. © 2013 Future Medicine Ltd.

Abstract: In colorectal cancer (CRC), inactivation of SMAD4 occurs early in the disease development and SMAD4 represents one of key driver genes in progression and metastasis. Loss of SMAD4 protein expression is a relatively common feature of sporadic colorectal cancers, and it was observed to be even more frequent in tumors of patients with early onset disease and also more frequent in microsatellite stable tumors. Pathogenic variants in the SMAD4 gene are usually missense or nonsense mutations, and they are more frequent in the C-terminal domain. The aim of this study was to perform genetic analysis of SMAD4 C-terminal domain in colorectal cancer patients with early onset disease and microsatellite stable tumors. This pilot study was conducted with a purpose of investigating if such genetic screening strategy would be useful for diagnostic purposes in this specific subgroup of CRC patients. The study was conducted in a selected set of DNA samples extracted from the tumors of CRC patients who had less than 50 years at the time of diagnosis. Genetic analysis of C-terminal domain has encompassed analysis of exons 9, 10, 11 and 12 of the SMAD4 gene by PCR and direct DNA sequencing. Among the twenty analyzed tumor DNAs, one sample was found to harbor a SMAD4 variant: NC_000018.9:g.48591918C > T; (NM005359.5: c.1081C > T; Arg361Cys). The variant was discovered in exon 9, affecting the codon 361, which represents a mutational hot spot within the SMAD4 gene. This variant was discovered in homozygous state in the tumor of a 47 yr old female with T3 stage carcinoma of the right colon. Considering the incidence and functional consequences of SMAD4 exon 9 variants, the screening of this region could be a useful low cost strategy for the genetic analysis of colorectal tumors from patients with early onset disease, as well as for susceptibility testing. © 2022, Allerton Press, Inc.

Abstract: In colorectal cancer (CRC), inactivation of SMAD4 occurs early in the disease development and SMAD4 represents one of key driver genes in progression and metastasis. Loss of SMAD4 protein expression is a relatively common feature of sporadic colorectal cancers, and it was observed to be even more frequent in tumors of patients with early onset disease and also more frequent in microsatellite stable tumors. Pathogenic variants in the SMAD4 gene are usually missense or nonsense mutations, and they are more frequent in the C-terminal domain. The aim of this study was to perform genetic analysis of SMAD4 C-terminal domain in colorectal cancer patients with early onset disease and microsatellite stable tumors. This pilot study was conducted with a purpose of investigating if such genetic screening strategy would be useful for diagnostic purposes in this specific subgroup of CRC patients. The study was conducted in a selected set of DNA samples extracted from the tumors of CRC patients who had less than 50 years at the time of diagnosis. Genetic analysis of C-terminal domain has encompassed analysis of exons 9, 10, 11 and 12 of the SMAD4 gene by PCR and direct DNA sequencing. Among the twenty analyzed tumor DNAs, one sample was found to harbor a SMAD4 variant: NC_000018.9:g.48591918C > T; (NM005359.5: c.1081C > T; Arg361Cys). The variant was discovered in exon 9, affecting the codon 361, which represents a mutational hot spot within the SMAD4 gene. This variant was discovered in homozygous state in the tumor of a 47 yr old female with T3 stage carcinoma of the right colon. Considering the incidence and functional consequences of SMAD4 exon 9 variants, the screening of this region could be a useful low cost strategy for the genetic analysis of colorectal tumors from patients with early onset disease, as well as for susceptibility testing. © 2022, Allerton Press, Inc.

Chronic inflammation in the terminal ileum (TI) suggests a cause for the patient's symptoms, especially when the clinical suspicion is Crohn's disease (CD). Clinic, laboratory, endoscopic, histopathological evaluation of patients is required for the diagnosis of CD. The most frequent localization of CD is the TI. There are many other diseases affecting the TI. Non-steroidal anti-inflammatory drug (NSAID) intake as well as other pathological conditions such as lymphoid hyperplasia, intestinal infections, lymphoma, infections and ulcerative colitis (UC) can mimic CD terminal ileitis. In this article the authors discuss these conditions, firstly in terms of differential diagnosis, and point out the facts that the clinicians must consider when they have a patient with terminal ileitis. Misdiagnosis of CD may be harmful to these patients because of inadequate response to therapy and occasionally an unnecessary operation may be performed. At the same time, the patients require appropriate treatment for their condition. © 2011 Hellenic Society of Gastroenterology.

[No abstract available]