Unraveling the Multifaceted Role of the miR-17-92 Cluster in Colorectal Cancer: From Mechanisms to Biomarker Potential.

Colorectal cancer (CRC) is a complex disease driven by intricate mechanisms, making it challenging to understand and manage. The miR-17-92 cluster has gained significant attention in CRC research due to its diverse functions and crucial role in various aspects of the disease. This cluster, consisting of multiple individual miRNAs, influences critical processes like tumor initiation, angiogenesis, metastasis, and the epithelial-mesenchymal transition (EMT). Beyond its roles in tumorigenesis and progression, miR-17-92's dysregulation in CRC has substantial implications for diagnosis, prognosis, and treatment, including chemotherapy responsiveness. It also shows promise as a diagnostic and prognostic biomarker, offering insights into treatment responses and disease progression. This review provides a comprehensive overview of recent advancements and the context-dependent role of the miR-17-92 cluster in colorectal cancer, drawing from the latest high-quality published data. It summarizes the established mechanisms governing miR-17-92 expression and the molecular pathways under its influence. Furthermore, it examines instances where it functions as an oncogene or a tumor suppressor, elucidating how cellular contexts dictate its biological effects. Ultimately, miR-17-92 holds promise as a biomarker for prognosis and therapy response, as well as a potential target for cancer prevention and therapeutic interventions. In essence, this review underscores the multifaceted nature of miR-17-92 in CRC research, offering promising avenues for enhancing the management of CRC patients.

Assessing the toxicity of pesticides exposure on hepatic miRNA-target gene alterations in rat liver tissues via molecular and integrated network bioinformatics analysis.

The prevalent use of pesticides, including pirimiphos-methyl (PPM) and bifenthrin (BF), poses a serious health risk, particularly to workers who encounter these chemicals daily. Despite the recognized hepatotoxic effects, the specific molecular mechanisms, especially those involving miRNAs in liver damage caused by PPM and BF, are not fully elucidated. Prior studies have not exhaustively analyzed the hepatic miRNA-target gene dynamics following exposure to these pesticides; thus, this research aims to fill that gap through an extensive miRNA analysis to discern their regulation in PPM or BF-induced hepatic toxicity. In this study, male Sprague-Dawley rats were exposed to BF or PPM for 28 days through oral gavage, simulating the chronic exposure faced by humans. We conducted a thorough assessment of the hepatotoxicity induced by PPM and BF, employing multiple evaluation levels, including histological analysis, liver enzyme measurements, and real-time PCR to detect changes in hepatic miRNA-target gene expressions. Additionally, we utilized DIANA-miRPath prediction tools to delineate the functional implications of these hepatic miRNA target genes. Our findings reveal a significant modulation in the expression of rno-miR-155-5p and rno-miR-122-5p, along with their target genes, following PPM and BF treatment. In contrast, rno-miR-21-5p levels remained unaltered. These observations suggest potential utility of these specific hepatic miRNAs as biomarkers for liver injury resulting from pesticide exposure. Subsequent GO enrichment analysis linked target genes to functions like molecular activity, protein binding, and cellular processes. Additionally, KEGG pathway analysis showed these genes, influenced by varied miRNA expressions, play significant roles in metabolic and signaling pathways In conclusion, this study enhances our comprehension of the biological roles of miRNAs in hepatic toxicity induced by PPM and BF. The insights gained here not only shed light on molecular mechanisms but also open avenues for considering these miRNAs as potential diagnostic biomarkers in conditions of pesticide-induced hepatotoxicity, thereby guiding future therapeutic strategies.

In Silico Evaluation of Coding and Non-Coding nsSNPs in the Thrombopoietin Receptor (MPL) Proto-Oncogene: Assessing Their Influence on Protein Stability, Structure, and Function.

The thrombopoietin receptor (MPL) gene is a critical regulator of hematopoiesis, and any alterations in its structure or function can result in a range of hematological disorders. Non-synonymous single nucleotide polymorphisms (nsSNPs) in MPL have the potential to disrupt normal protein function, prompting our investigation into the most deleterious MPL SNPs and the associated structural changes affecting protein-protein interactions. We employed a comprehensive suite of bioinformatics tools, including PredictSNP, InterPro, ConSurf, I-Mutant2.0, MUpro, Musitedeep, Project HOPE, STRING, RegulomeDB, Mutpred2, CScape, and CScape Somatic, to analyze 635 nsSNPs within the MPL gene. Among the analyzed nsSNPs, PredictSNP identified 28 as significantly pathogenic, revealing three critical functional domains within MPL. Ten of these nsSNPs exhibited high conservation scores, indicating potential effects on protein structure and function, while 14 were found to compromise MPL protein stability. Although the most harmful nsSNPs did not directly impact post-translational modification sites, 13 had the capacity to substantially alter the protein's physicochemical properties. Some mutations posed a risk to vital protein-protein interactions crucial for hematological functions, and three non-coding region nsSNPs displayed significant regulatory potential with potential implications for hematopoiesis. Furthermore, 13 out of 21 nsSNPs evaluated were classified as high-risk pathogenic variants by Mutpred2. Notably, amino acid alterations such as C291S, T293N, D295G, and W435C, while impactful on protein stability and function, were deemed non-oncogenic "passenger" mutations. Our study underscores the substantial impact of missense nsSNPs on MPL protein structure and function. Given MPL's central role in hematopoiesis, these mutations can significantly disrupt hematological processes, potentially leading to a variety of disorders. The identified high-risk pathogenic nsSNPs may hold promise as potential biomarkers or therapeutic targets for hematological diseases. This research lays the foundation for future investigations into the MPL gene's role in the realm of hematological health and diseases.

Altered Expression of Vitamin D Metabolism Genes and Circulating MicroRNAs in PBMCs of Patients with Type 1 Diabetes: Their Association with Vitamin D Status and Ongoing Islet Autoimmunity.

BACKGROUND: The immunomodulatory role of 1,25-Dihydroxy vitamin D3 (1,25(OH)2D3) is exerted through its interaction with the vitamin D receptor (VDR) present on pancreatic and immune cells. While a deficiency in vitamin D has been linked to Type 1 Diabetes Mellitus (T1DM), the exact molecular mechanism driving this down-regulation in T1DM is yet to be fully understood. This study aimed to decipher differences in the expression of genes associated with vitamin D metabolism in T1DM patients and to ascertain if there is a correlation between serum 1,25(OH)2D3 levels and the expression of these genes. We also sought to understand the influence of specific microRNAs (miRNAs) on the expression of vitamin D metabolism genes in peripheral blood mononuclear cells (PBMCs) of T1DM patients. Furthermore, the study delved into the potential implications of altered vitamin D metabolism genes and miRNAs on autoimmune processes. METHODS: Utilizing real-time PCR, we assessed the expression profiles of genes encoding for 1-hydroxylases (CYP27B1) and 24-hydroxylases (CYP24A1), as well as related miRNAs, in PBMCs from 30 T1DM patients and 23 healthy controls. ELISA tests facilitated the measurement of 1,25(OH)2D3, GAD65, and IA-2 levels. RESULTS: Our findings showcased downregulated CYP27B1 mRNA levels, while CYP24A1 expression remained stable compared to healthy subjects (CYP27B1, p = 0.0005; CYP24A1, p = 0.205, respectively). In T1DM patients, the levels of has-miR-216b-5p were found to be increased, while the levels of has-miR-21-5p were decreased in comparison to the control group. Notably, no correlation was identified between the expression of CYP27B1 in T1DM patients and the levels of has-miR-216b-5p, has-miR-21-5p, and 1,25(OH)2D3. A significant negative correlation was identified between CYP27B1 mRNA levels in PBMCs of T1DM and IA2, but not with GAD65. CONCLUSIONS: The study highlights there were reduced levels of both CYP27B1 mRNA and has-miR-21-5p, along with elevated levels of has-miR-216b-5p in the PBMCs of T1DM. However, the absence of a correlation between the expression of CYP27B1, levels of has-miR-216b-5p, and the status of 1,25(OH)2D3 suggests the possible existence of other regulatory mechanisms. Additionally, the inverse relationship between IA2 autoantibodies and CYP27B1 expression in T1DM patients indicates a potential connection between this gene and the autoimmune processes inherent in T1DM.

Comprehensive In Silico Characterization of the Coding and Non-Coding SNPs in Human Dectin-1 Gene with the Potential of High-Risk Pathogenicity Associated with Fungal Infections.

The human C-type lectin domain family 7 member A (CLEC7A) gene encodes a Dectin-1 protein that recognizes beta-1,3-linked and beta-1,6-linked glucans, which form the cell walls of pathogenic bacteria and fungi. It plays a role in immunity against fungal infections through pathogen recognition and immune signaling. This study aimed to explore the impact of nsSNPs in the human CLEC7A gene through computational tools (MAPP, PhD-SNP, PolyPhen-1, PolyPhen-2, SIFT, SNAP, and PredictSNP) to identify the most deleterious and damaging nsSNPs. Further, their effect on protein stability was checked along with conservation and solvent accessibility analysis by I-Mutant 2.0, ConSurf, and Project HOPE and post-translational modification analysis using MusiteDEEP. Out of the 28 nsSNPs that were found to be deleterious, 25 nsSNPs affected protein stability. Some SNPs were finalized for structural analysis with Missense 3D. Seven nsSNPs affected protein stability. Results from this study predicted that C54R, L64P, C120G, C120S, S135C, W141R, W141S, C148G, L155P, L155V, I158M, I158T, D159G, D159R, I167T, W180R, L183F, W192R, G197E, G197V, C220S, C233Y, I240T, E242G, and Y3D were the most structurally and functionally significant nsSNPs in the human CLEC7A gene. No nsSNPs were found in the predicted sites for post-translational modifications. In the 5' untranslated region, two SNPs, rs536465890 and rs527258220, showed possible miRNA target sites and DNA binding sites. The present study identified structurally and functionally significant nsSNPs in the CLEC7A gene. These nsSNPs may potentially be used for further evaluation as diagnostic and prognostic biomarkers.

The effectiveness of scenario-based virtual laboratory simulations to improve learning outcomes and scientific report writing skills.

The use of virtual laboratory simulations in various disciplines, which provide important educational benefits, has increased. Several studies show that laboratory activities, including scenario-based virtual laboratory simulation (SB-VLS), stimulate cognitive and non-cognitive skills. However, the effects of the SB-VLS when integrated into molecular biology courses, on the development of cognitive skills, such as scientific report writing skills, remain unexplored. A pre-post-test, randomized, quasi-experimental design was used. Thirty-five female students were randomly assigned to experimental or control groups. The control group (n = 17) attended a traditional lecture and video lab demonstration (VLD), while the experimental group (n = 18) participated in SB-VLS on molecular cloning. Findings revealed statistically significant differences, with large effects sizes in the SB-VLS group between pre- and post-test in intrinsic motivation (2.9 vs 3.86, p = 0.042, Cohen's d = 4.17), self-efficacy (3.31 vs 3.85, p = 0.002, Cohen's d = 1.071), and knowledge gain scales (50.93 vs 75.93, p = 0.001, Cohen's d = 1.46). Moreover, between-group effect sizes of the experimental and control groups were also large for intrinsic motivation (dppc2 = 1.441), self-efficacy (dppc2 = 0.766), and knowledge (dppc2 = 1.147), indicating that the effect of the SB-VLS was significant, which may be due to the activities and techniques used in SB-VLS to develop learning outcomes. Additionally, the SB-VLS group had statistically better lab report scores as compared to the control group (3.92 vs. 4.72, p < 0.0001). Collectively, our data show that SB-VLS is an innovative teaching strategy and an effective tool for developing non-cognitive and cognitive skills, especially scientific report writing skills.

Regulation of estrogen receptor ß1 expression in breast cancer by epigenetic modification of the 5' regulatory region.

ERß1 is often down-regulated in breast cancer compared to normal breast but mechanisms surrounding this are unclear. We examined whether loss of heterozygosity (LOH) or methylation at ERß promoters (0N, 0K) and/or untranslated exon 0N were involved in ERß down-regulation in breast cancer tissues and cell lines and if treatment with the de-methylating agent 5-aza-deoxycytidine and/or the histone deacetylase inhibitor Trichostatin A could influence expression in vitro. We found no evidence of correlation between LOH at 14q22-24 (genomic locus containing ERß/ESR2), and ERß1 expression in primary breast cancers. A negative correlation between ERß1 mRNA expression and methylation status was observed for promoter 0N in BT-20, MDA-MB-453 and T47D cells. Promoter 0K was consistently unmethylated. In primary breast tumours, methylation of the untranslated exon 0N, downstream of promoter 0N, but not of promoter 0N itself, correlated with down-regulation of ERß. In MDA-MB-453 cells, treatment with 5-aza-deoxycytidine was sufficient to induce ERß1 expression from the 0N promoter while in BT-20 both agents were required. Examination of various sites on ESR2 highlighted epigenetic but not genetic regulation of ERß1. In particular methylation adjacent to promoter 0N was a key regulatory event for ERß1 silencing. A combination of de-methylating agents and histone deacetylase inhibitors fully restored ERß1 expression which may offer a novel therapeutic angle for breast cancer management.

Estrogen receptor {beta}1 expression is regulated by miR-92 in breast cancer.

Estrogen receptor beta1 (ERbeta1) downregulation occurs in many breast cancers, but the responsible molecular mechanisms remain unclear. Here, we report that levels of ERbeta1 expression are negatively regulated by the microRNA miR-92. Expression analysis in a cohort of primary breast tumors confirmed a significant negative correlation between miR-92 and both ERbeta1 mRNA and protein. Inhibition of miR-92 in MCF-7 cells increased ERbeta1 expression in a dose-dependent manner, whereas miR-92 overexpression led to ERbeta1 downregulation. Reporter constructs containing candidate miR-92 binding sites in the 3'-untranslated region (UTR) of ERbeta1 suggested by bioinformatics analysis confirmed that miR-92 downregulated ERbeta1 via direct targeting of its 3'-UTR. Our results define a potentially important mechanism for downregulation of ERbeta1 expression in breast cancer.