BAT25, ACVR2, and TGFBR2 Mononucleotide STR Markers: A Triplex Panel for Microsatellite Instability Testing in Colorectal Tumors.

Background: Microsatellite instability (MSI) in colorectal cancer (CRC) patients is considered as a diagnostic and prognostic marker. MSI is a consequence of mismatch repair deficiency which is evaluated using the different microsatellite markers on the whole genome. In this pilot study, the diagnostic value of a novel triplex panel including three mononucleotide markers has been evaluated in comparison to the standard Promega kit for MSI testing in CRC patients with Amsterdam II criteria. Materials and Methods: DNA extracted from tumors and normal Formalin-Fixed Paraffin-Embedded (FFPE) tissues of index cases from 37 HNPCC (Hereditary non-polyposis colorectal cancer) families were evaluated for MSI state. Primer design for three markers, including BAT25, ACVR2, and TGFBR2, was performed using 19 nucleotides of the M-13 phage. The instability of each marker was assessed through fragment analysis in comparison with Promega kit markers for all patients. The sensitivity and specificity of each marker have been calculated. Results: The comparative evaluation of MSI in both tumors and normal adjacent FFPE tissues demonstrated a separate sensitivity as 100%, 83.3%, and 76.9% for BAT25, ACVR2, and TGFBR2, respectively, and 100% sensitivity in the form of a triplex. Moreover, the specificity for each of these three markers in MSI testing was estimated as 100%, separately and in the form of the triplex in comparison with the Promega pentaplex standard Kit. Conclusions: A high sensitivity and specificity for the novel triplex panel in MSI-testing were estimated among Iranian patients. More studies are recommended to confirm this panel as a diagnostic kit for MSI testing.

EEG artifact removal using sub-space decomposition, nonlinear dynamics, stationary wavelet transform and machine learning algorithms.

Blind source separation (BSS) methods have received a great deal of attention in electroencephalogram (EEG) artifact elimination as they are routine and standard signal processing tools to remove artifacts and reserve desired neural information. On the other hand, a classifier should follow BSS methods to automatically identify artifactual sources and remove them in the following steps. In addition, removing all detected artifactual components leads to loss of information since some desired information related to neural activity leaks to these sources. So, an approach should be employed to detect and suppress the artifacts and reserve neural activity. This study introduces a novel method based on EEG and Poincare planes in the phase space to detect artifactual components estimated by second-order blind identification (SOBI). Artifacts are detected using a mixture of well-known conventional classifiers and were removed employing stationary wavelet transform (SWT) to reserve neural information. The proposed method is a combination of signal processing techniques and machine learning algorithms, including multi-layer perceptron (MLP), K-nearest neighbor (KNN), naïve Bayes, and support vector machine (SVM) which have significant results while applying our proposed method to different scenarios. Simulated, semi-simulated, and real EEG signals are employed to evaluate the proposed method, and several evaluation criteria are calculated. We achieved acceptable results, for example, 98% average accuracy and 97% average sensitivity in artifactual EEG component detection or about 2% as mean square error in EEG reconstruction after artifact removal. Results showed that the proposed method is effective and can be used in future studies as we have considered different real-world scenarios to evaluate it.

Vitamin D can be effective on the prevention of COVID-19 complications: A narrative review on molecular aspects.

The widespread COVID-19 pandemic has been, currently, converted to a catastrophic human health challenge. Vitamin D (VD) and its metabolites have been used as a palliative treatment for chronic inflammatory and infectious diseases from ancient times. In the current study, some molecular aspects of the potential effects of VD against COVID-19 side-effects have been discussed. An arguable role in autophagy or apoptosis control has been suggested for VD through calcium signaling at the mitochondrial and ER levels. 1,25(OH)2D3 is also an immunomodulator that affects the development of B-cells, T-cells, and NK cells in both innate and acquired immunity. The production of some anti-microbial molecules such as defensins and cathelicidins is also stimulated by VD. The overexpression of glutathione, glutathione peroxidase, and superoxide dismutase, and down-regulation of NADPH oxidase are induced by VD to reduce the oxidative stress. Moreover, the multi-organ failure due to a cytokine storm induced by SARS-CoV2 in COVID-19 may be prevented by the immunomodulatory effects of VD. It can also downregulate the renin-angiotensin system which has a protective role against cardiovascular complications induced by COVID-19. Given the many experimental and molecular evidences due to the potential protective effects of VD on the prevention of the COVID-19-induced morbidities, a VD supplementation is suggested to prevent the lethal side-effects of the infection. It is particularly recommended in VD-deficient patients or those at greater risk of serious or critical effects of COVID-19, including the elderly, and patients with pre-existing chronic diseases, especially those in nursing homes, care facilities, and hospitals.

A Simplified Protocol for Microsatellite Instability Evaluation in Iranian Patients at Risk for Lynch Syndrome.

OBJECTIVE: The most important tumor characteristic of Lynch syndrome (LS) is microsatellite instability (MSI). In the current study, BAT34c4 and BAT26 mononucleotide markers were evaluated as part of efforts to test a cost-effective panel for MSI testing in Iranian patients, comparing it with the Promega kit. METHODS: Amsterdam II clinical criteria were used to identify patients at risk for LS. The MSI status of these patients was determined using BAT34c4 and BAT26 markers, as well as the Promega kit. The results of both methods were compared, and the sensitivity and specificity of new short tandem repeat (STR) markers were estimated using statistical formulas. RESULTS: Of the 37 patients we studied who were at risk for LS, 27% showed MSI-high results, via the Promega kit. The same results were achieved for BAT34c4 and BAT26 separately. CONCLUSIONS: The novel 2-marker kit for MSI testing has similar accuracy as the Promega kit at a lower cost, due to fewer markers and a more economical labeling method.

WRN Germline Mutation Is the Likely Inherited Etiology of Various Cancer Types in One Iranian Family.

BACKGROUND: Familial cancers comprise a considerable distribution of colorectal cancers (CRCs), of which only about 5% occurs through well-established hereditary syndromes. It has been demonstrated that deleterious variants at the newly identified cancer-predisposing genes could describe the etiology of undefined familial cancers. METHODS: The present study aimed to identify the genetic etiology in a 32-year-old man with early onset familial CRC employing several molecular diagnostic techniques. DNA was extracted from tumoral and normal formalin-fixed-paraffin-embedded (FFPE) blocks, and microsatellite instability (MSI) was evaluated. Immunohistochemistry staining of MMR proteins was performed on tumoral FFPE blocks. Next-generation sequencing (NGS), multiplex ligation-dependent amplification (MLPA) assay, and Sanger sequencing were applied on the genomic DNA extracted from peripheral blood. Data analysis was performed using bioinformatics tools. Genetic variants interpretation was based on ACMG. RESULTS: MSI analysis indicated MSI-H phenotype, and IHC staining proved no expressions of MSH2 and MSH6 proteins. MLPA and NGS data showed no pathogenic variants in MMR genes. Further analysis of NGS data revealed a candidate WRN frameshift variant (p.R389Efs*3), which was validated with Sanger sequencing. The variant was interpreted as pathogenic since it met the criteria based on the ACMG guideline including very strong (PVS1), strong (PS3), and moderate (PM2). CONCLUSION: WRN is a DNA helicase participating in DNA repair pathways to sustain genomic stability. WRN deficient function may contribute to CRC development that is valuable for further investigation as a candidate gene in hereditary cancer syndrome diagnosis.