Simplified microsatellite instability detection protocol provides equivalent sensitivity to robust detection strategies in Lynch syndrome patients

Objective: Germline mutations in mismatch repair (MMR) genes cause Lynch syndrome (LS). LS is an inherited disease, and an important consequence of MMR deficiency is microsatellite instability (MSI) phenotype. MSI phenotype influences the efficacy of 5 fluorouracil (5-FU) chemotherapy. Reproducible, cost effective, and easy to perform laboratory tests are required to include MSI detection in routine laboratory practice. Evaluation of CAT25 as monomorphic short tandem repeat sequence enables CAT25 to be an efficient screening tool among hereditary nonpolyposis colorectal cancer (HNPCC) patients compared with other methods used currently. Methods: Based on Amsterdam II criteria, 31 patients in 31 families were shortlisted from a total number of 1,659 colorectal cancer patients. MSI status was examined in these patients using CAT25 and a commercially available Promega MSI five-marker-based detection system as well as immunohistochemical (IHC) staining of four important MMR proteins. Patients were scored as high microsatellite instable (MSI-H), low (MSI-L), or stable (MSS). MSI status determined by CAT25 single mononucleotide marker was compared with that of five mononucleotide markers, Promega commercial kit, and IHC method. Results: MMR protein deficiency was observed on 7/31 probands using IHC methodology and 6/31 categorized as MSI-H using commercial kit or CAT25 single marker. The sensitivity and specificity of the CAT25 single marker were the same as those detected by five-marker Promega commercial kit in our patients. Conclusions: Based on our results, the performance of the CAT25 single mononucleotide marker for MSI status determination in our HNPCC patients is the same as that of the five-marker-based commercial kit

MT1XT20 single quasi-monomorphic mononucleotide marker for detection of microsatellite instability in iranian patients with hereditary nonpolyposis colorectal cancer (HNPCC)

Background: Colorectal malignancies with high microsatellite instability (MSI-H), either hereditary or sporadic, demonstrate better prognosis, altered response to fluorouracil (5FU) chemotherapy and altered operative approach. It is now recommended to perform MSI testing for all new cases of colorectal cancers regardless of being categorized as hereditary or sporadic. This study aimed to evaluate MT1XT20 mononucleotide marker in Iranian patients with hereditary nonpolyposis colorectal cancer (HNPCC). The samples were further characterized using Promega five-marker MSI testing panel and immunohistochemical (IHC) technique. Methods: MT1XT20 mononucleotide marker and commercially available kit (Promega, USA) incorporating five quasi-monomorphic markers were studied in 20 cases of HNPCC using polymerase chain reaction (PCR) technique. IHC was performed to evaluate the status of all four important mismatch repair (MMR) proteins, too. Findings: Eight (40%), seven (35%) and five (25%) cases showed MSI using Promega kit, IHC and MT1XT20, respectively. Among the markers included in Promega kit, BAT26 marker with instability in all 8 samples (100%) was the most instable marker. NR24 and NR21 markers showed instability in 7 cases (87.5%); BAT25 and MONO 27 markers were instable in 6 (75.0%) and 5 (62.5%) specimens, respectively. Conclusion: Although MT1XT20 is considered as a valid single marker in Italian population, it seems this is not hold true about the Iranian patients. Instead, BAT26 among the markers included in Promega MSI testing was shown instability in all 8 samples of MSI-H colorectal cancer (CRC). Therefore, it may be concluded that BAT26 alone is as efficient as the cohort of five markers in Iranian patients. © 2016, Isfahan University of Medical Sciences(IUMS). All rights reserved

Evaluation of MT1XT20 single quasi-monomorphic mononucleotide marker for characterizing microsatellite instability in persian lynch syndrome patients

Background: Colorectal malignancies with high microsatellite instability (MSI-H), either hereditary (Lynch syndrome) or sporadic, demonstrate better prognosis and altered response to 5FU chemotherapy. It is now recommended to perform MSI testing for all new cases of colorectal cancer regardless of being categorized as hereditary or sporadic. For MSI detection, immunohistochemistry or PCR-based protocols using a cohort of various sets of STR markers are recommended. Here we aimed to evaluate a simplified protocol using just a single STR marker, MT1XT20 mononucleotide repeat, for detection of MSI in Lynch syndrome patients. A Promega five-marker MSI testing panel and immunohistochemistry (IHC) were used as the gold standard in conjunction with MT1XT20. Materials and Methods: Colorectal patients with a positive history of familial cancers were selected by evaluating medical records. Based on Amsterdam II criteria for Lynch syndrome 20 families were short listed. DNA was extracted from formalin fixed paraffin embedded tumour and adjacent normal tissues resected from the index case in each family. Extracted DNA was subjected to MT1XT20 mononucleotide marker analysis and assessment with a commercially available five marker MSI testing kit (Promega, USA). IHC also was performed on tissue sections and the results were compared with PCR based data. Results: Eight (40%), seven (35%) and five (25%) cases were MSI positive using with the Promega kit, IHC and MT1XT20, respectively. Among the markers included in Promega kit, BAT26 marker showed instability in all 8 samples. NR24 and NR21 markers showed instability in 7 (87.5%), and BAT25 and MONO 27 in 6 (75%) and 5 (62.5%). Conclusions: Although MT1XT20 was earlier reported as a valid standalone marker for MSI testing in CRC patients, we could not verify this in our Iranian patients. Instead BAT26 among the markers included in Promega MSI testing kit showed instability in all 8 MSI-H CRC samples. Therefore, it seems BAT26 could act well as a single marker for MSI testing in Iranian CRC patients

Harnessing CRISPR/Cas9 technology in cardiovascular disease

The CRISPR/Cas9 system is a precisely targeted bacterial defense system, used to control invading viruses. This technology has many potential applications including genetic changes in somatic and germ cells and the creation of knockout animals. Compared to other genome editing techniques such as zinc-finger nucleases and transcription activator-like effector nucleases (TALENS), the CRISPR/Cas9 system is much easier and more efficient. Most importantly, the multifunctional capacity of this technology allows simultaneous editing of several genes. The CRISPR/Cas9 system also potentially has the ability to prevent and treat human diseases. The present article addresses some key points related to the use of the CRISPR/Cas9 system as a powerful tool in cardiovascular research and as a new strategy for the treatment of cardiovascular disease (CVD)

Psychometric properties of Persian version of child and youth resilience measure-revised in children

BACKGROUND: Resilience is both the individuals' capacity to navigate their way to the resources that sustain their well-being in the context of exposure to adversity and their capacity to negotiate for resources to be accessed. Hence, it is crucial for clinical settings and research centers to have access to a valid and reliable scale that can measure different components of resilience. This study aimed to determine the psychometric properties and cultural adaptation of the Persian version of the Child and Youth Resilience Measure-revised (CYRM-R) in Children. MATERIALS AND METHODS: This cross-sectional study includes the standard procedure of translation of the CYRM-R and Person Most Knowledgeable–Child and Youth Resilience Measure–revised (PMK-CYRM-R), exploration of the goodness-of-fit, and confirmatory factor analysis (CFA) of a sample of 200 parents or caregivers and their children aged 5 to 9 years who were selected by convenient sampling in Tehran, Iran. CYRM-R, PMK-CYRM-R, and The Strengths and Difficulties Questionnaire (SDQ) were completed by participants. Also, internal consistency, face, content, and criterion validity were investigated. RESULTS: A two-factor structure of CYRM-R for Iranian children was identified by CFA: Personal and Caregiver. Results indicated adequate goodness-of-fit and strong internal consistency (Cronbach's alpha = 0.88). Acceptable face, content, and criterion validity of the CYRM-R were reported by positive correlation to the PMK-CYRM-R. No significant relation was found between CYRM-R and SDQ. CONCLUSION: Findings of the present study support the robust psychometric properties and cultural adaptation of the CYRM-R in Iranian children

The Role of Efferocytosis in Autoimmune Diseases

Apoptosis happens continuously for millions of cells along with the active removal of apoptotic debris in order to maintain tissue homeostasis. In this respect, efferocytosis, i.e., the process of dead cell clearance, is orchestrated through cell exposure of a set of “find me,” “eat me,” and “tolerate me” signals facilitating the engulfment of dying cells through phagocytosis by macrophages and dendritic cells. The clearance of dead cells via phagocytes is of utmost importance to maintain the immune system tolerance to self-antigens. Accordingly, this biological activity prevents the release of autoantigens by dead cells, thus potentially suppressing the undesirable autoreactivity of immune cells and the appearance of inflammatory autoimmune disorders as systemic lupus erythematous and rheumatoid arthritis. In the present study, the apoptosis pathways and their immune regulation were reviewed. Moreover, efferocytosis process and its impairment in association with some autoimmune diseases were discussed. Keywords: apoptosis, efferocytosis, autoimmune disease, phagocytosis, systemic lupus erythematou