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• Kong, Xiang Yi; Huse, Camilla; Yang, Kuan; Øgaard, Jonas; Jimenez, Natalia Berges & Vik, Erik Sebastian [Show all 24 contributors for this article] (2021). Endonuclease v regulates atherosclerosis through c-c motif chemokine ligand 2-mediated monocyte infiltration. Journal of the American Heart Association (JAHA). 10(14). doi: 10.1161/JAHA.120.020656. Full text in Research Archive Show summary

  Background: In cardiovascular diseases, atherosclerotic disorder are the most frequent and important with respect to morbidity and mortality. Inflammation mediated by immune cells is central in all parts of the atherosclerotic progress, and further understanding of the underlying mechanisms is needed. Growing evidence suggests that deamination of adenosine‐to‐inosine in RNA is crucial for a correct immune response; nevertheless, the role of adenosine‐to‐inosine RNA editing in atherogenesis has barely been studied. Several proteins have affinity for inosines in RNA, one being ENDOV (endonuclease V), which binds and cleaves RNA at inosines. Data on ENDOV in atherosclerosis are lacking. Methods and Results: Quantitative polymerase chain reaction on ENDOV mRNA showed an increased level in human carotid atherosclerotic plaques compared with control veins. Inosine‐ribonuclease activity as measured by an enzyme activity assay is detected in immune cells relevant for the atherosclerotic process. Abolishing EndoV in atherogenic apolipoprotein E‐deficient (ApoE−/−) mice reduces the atherosclerotic plaque burden, both in size and lipid content. In addition, in a brain stroke model, mice without ENDOV suffer less damage than control mice. Finally, lack of EndoV reduces the recruitment of monocytes to atherosclerotic lesions in atherogenic ApoE−/− mice. Conclusions: ENDOV is upregulated in human atherosclerotic lesions, and data from mice suggest that ENDOV promotes atherogenesis by enhancing the monocyte recruitment into the atherosclerotic lesion, potentially by increasing the effect of CCL2 activation on these cells.

• Kong, Xiang Yi; Vik, Erik Sebastian; Nawaz, Meh Sameen; Berges, Natalia; Dahl, Tuva Børresdatter & Vågbø, Cathrine [Show all 17 contributors for this article] (2020). Deletion of Endonuclease V suppresses chemically induced hepatocellular carcinoma. Nucleic Acids Research (NAR). ISSN 0305-1048. 48(8), p. 4463–4479. doi: 10.1093/nar/gkaa115. Full text in Research Archive Show summary

  Endonuclease V (EndoV) is a conserved inosine-specific ribonuclease with unknown biological function. Here, we present the first mouse model lacking EndoV, which is viable without visible abnormalities. We show that endogenous murine EndoV cleaves inosine-containing RNA in vitro, nevertheless a series of experiments fails to link an in vivo function to processing of such transcripts. As inosine levels and adenosine-to-inosine editing often are dysregulated in hepatocellular carcinoma (HCC), we chemically induced HCC in mice. All mice developed liver cancer, however, EndoV−/− tumors were significantly fewer and smaller than wild type tumors. Opposed to human HCC, adenosine deaminase mRNA expression and site-specific editing were unaltered in our model. Loss of EndoV did not affect editing levels in liver tumors, however mRNA expression of a selection of cancer related genes were reduced. Inosines are also found in certain tRNAs and tRNAs are cleaved during stress to produce signaling entities. tRNA fragmentation was dysregulated in EndoV−/− livers and apparently, inosine-independent. We speculate that the inosine-ribonuclease activity of EndoV is disabled in vivo, but RNA binding allowed to promote stabilization of transcripts or recruitment of proteins to fine-tune gene expression. The EndoV−/− tumor suppressive phenotype calls for related studies in human HCC.

• Berges, Natalia; Nawaz, Meh Sameen; Dahl, Tuva Børresdatter; Hagen, Lars; Bjørås, Magnar & Lærdahl, Jon Kristen [Show all 7 contributors for this article] (2019). Complex alternative splicing of human Endonuclease V mRNA, but evidence for only a single protein isoform. PLOS ONE. 14(11). doi: 10.1371/journal.pone.0225081. Full text in Research Archive Show summary

  Endonuclease V (ENDOV) is a ribonuclease with affinity for inosine which is the deamination product of adenosine. The genomes of most organisms, including human, encode ENDOV homologs, yet knowledge about in vivo functions and gene regulation is sparse. To contribute in this field, we analyzed mRNA and protein expression of human ENDOV (hENDOV). Analyses of public sequence databases revealed numerous hENDOV transcript variants suggesting extensive alternative splicing. Many of the transcripts lacked one or more exons corresponding to conserved regions of the ENDOV core domain, suggesting that these transcripts do not encode for active proteins. Three complete transcripts were found with open reading frames encoding 282, 308 and 309 amino acids, respectively. Recombinant hENDOV 308 and hENDOV 309 share the same cleavage activity as hENDOV 282 which is the variant that has been used in previous studies of hENDOV. However, hENDOV 309 binds inosine-containing RNA with stronger affinity than the other isoforms. Overexpressed GFP-fused isoforms were found in cytoplasm, nucleoli and arsenite induced stress granules in human cells as previously reported for hENDOV 282. RT-qPCR analysis of the 3’-termini showed that hENDOV 308 and hENDOV 309 transcripts are more abundant than hENDOV 282 transcripts in immortalized cell lines, but not in primary cells, suggesting that cells regulate hENDOV mRNA expression. In spite of the presence of all three full-length transcripts, mass spectrometry analyses identified peptides corresponding to the hENDOV 309 isoform only. This result suggests that further studies of human ENDOV should rather encompass the hENDOV 309 isoform.

• Nawaz, Meh Sameen; Vik, Erik Sebastian; Berges, Natalia; Fladeby, Cathrine; Bjørås, Magnar & Dalhus, Bjørn [Show all 7 contributors for this article] (2016). Regulation of Human Endonuclease V Activity and Relocalization to Cytoplasmic Stress Granules. Journal of Biological Chemistry. ISSN 0021-9258. 291(41), p. 21786–21801. doi: 10.1074/jbc.M116.730911. Full text in Research Archive
• Nawaz, Meh Sameen; Vik, Erik Sebastian; Ronander, Mia Elise; Solvoll, Anne Marthe; Blicher, Pernille & Bjørås, Magnar [Show all 8 contributors for this article] (2016). Crystal structure and MD simulation of mouse EndoV reveal wedge motif plasticity in this inosine-specific endonuclease. Scientific Reports. 6. doi: 10.1038/srep24979. Full text in Research Archive
• Vik, Erik Sebastian; Nawaz, Meh Sameen; Andersen, Pernille Strøm; Fladeby, Cathrine; Bjørås, Magnar & Dalhus, Bjørn [Show all 7 contributors for this article] (2013). Endonuclease V cleaves at inosines in RNA. Nature Communications. 4. doi: 10.1038/ncomms3271. Full text in Research Archive

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• Nawaz, Meh Sameen (2026). Mandatory vs. Optional: How Course Integration Drives Student Engagement with Virtual Laboratory Simulations. Full text in Research Archive
• Nawaz, Meh Sameen (2026). Virtuelle Labsimuleringer: Obligatorisk eller frivillig? Full text in Research Archive
• Nawaz, Meh Sameen (2026). Gamifiseringsplattform for biologistudenter. Full text in Research Archive
• Nawaz, Meh Sameen & Tahiri, Andliena (2025). Extracellular Vesicle-Associated Cytokines. Full text in Research Archive
• Nawaz, Meh Sameen; Minh, Hang; Jabeen, Shakila; Bjørnetrø, Tonje; Geisler, Jürgen & Kristensen, Vessela N. [Show all 7 contributors for this article] (2025). Extracellular Vesicle-Associated Cytokines as Novel Biomarkers in ER+ Breast Cancer. Full text in Research Archive
• Nawaz, Meh Sameen (2025). Virtuelle Labsimuleringer: Hva Motiverer Studentene til Å Delta? Full text in Research Archive
• Nawaz, Meh Sameen (2024). Forskerne utvikler skreddersøm i behandlingen av brystkreft. Kunnskap Kristiania. Full text in Research Archive
• Fjermeros, Kamilla; Ghannoum, Salim; Geisler, Stephanie; Bhargava, Sameer; Tahiri, Andliena & Klajic, Jovana [Show all 32 contributors for this article] (2024). The NEOLETRIB trial: neoadjuvant treatment with Letrozole and Ribociclib in ER-positive, HER2-negative breast cancer. Future Oncology. ISSN 1479-6694. 20(32), p. 2457–2466. doi: 10.1080/14796694.2024.2377531. Full text in Research Archive Show summary

  Chemotherapy is used as neoadjuvant therapy for all subgroups of breast cancer, including ER-positive, and HER2-negative cases. However, studies have suggested that using aromatase inhibitors combined with CDK4/6-inhibitors might be an appropriate alternative in selected patients. Thus, the NEOLETRIB trial evaluates the response of ER-positive, HER2-negative luminal A/B breast cancer to the combination of letrozole and ribociclib in the neoadjuvant setting. Comprehensive molecular biology procedures, including sequential single-cell RNA-sequencing of tumor biopsies, are performed during 6 months of treatment with extensive biobanking of blood samples, tumor biopsies and gut microbiome specimens. Our findings will hopefully contribute to an improved selection of patients who may benefit from this drug combination and give new insights into the intra-tumoral changes during this treatment.

• Strand, Martin Frank; Skjerve, Hilde; Nawaz, Meh Sameen & Aqrawi, Lara Adnan (2024). Studentaktiviserende semesteroppgave med muntlig justering innen biomedisinske fag. Full text in Research Archive
• Dalhus, Bjørn; Vik, Erik Sebastian; Rosnes, Ida; Nawaz, Meh Sameen; Fladeby, Cathrine & Tainer, John A [Show all 8 contributors for this article] (2014). DNA AND RNA SUBSTRATE PREFERENCES OF ENDONUCLEASE V – IMPLICATIONS FOR THE BIOLOGICAL ROLE. Full text in Research Archive

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