Virginia Via Research Day Book 2026

1. Zachary Morris, 2. Liyan Zhang, 2. Kayla Duxbury, 2. James Romero-Masters, PhD Corresponding author:zmorris@vt.vcom.edu 06 MMUPV1 E6 IMPAIRS NF- κ B SIGNALING TO PROMOTE SQUAMOUS CELL CARCINOMA Medical Student Research Biomedical 1. VCOM-Virginia, Blacksburg, Virginia 2. Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia

NF-κB signaling and alters c-Myc expression, and to evaluate how these changes may contribute to SCC development. Methods: To determine if the NF-κB signaling pathway was influenced by mE6, we performed RNA seq analysis on mE6-expressing mouse keratinocytes . RNAseq data was subject to gene set enrichment analysis (GSEA) on the Hallmark gene set “TNFα signaling via NFKB”. This prompted us to perform immunoprecipitation and immunoblot assays on mE6 and E6R130A (a defective mE6 mutant) to further define the molecular changes observed. To demonstrate the significance of this pathway in vivo, we performed immunohistochemistry (IHC) to stain nuclear NF-kB1 infected and uninfected tissue. To define mE6's impact on c-Myc expression, we performed immunoblot on mE6 and E6R130A. Results: The GSEA showed a significant signal reduction in mE6 and the NFKB gene set. Furthermore, our immunoprecipitation experiments showed that mE6 interacted with the entire IKK complex of the NF-kB pathway (IKKα, IKKβ, and

IKKγ), while the E6R130A mutant is defective for binding the IKK complex. mE6’s interaction with the IKK complex resulted in decreased phosphorylation of p65 and a lack of activation of NF-κB1 and NF-κB2. In addition, the immunoblots also showed a significant increase of nuclear IKKα. The IHC demonstrated a complete absence of nuclear stained NF-kB1 when compared with uninfected tissue. Lastly, the c-Myc immunoblot showed a significant increase in expression in mE6 compared to vector control and E6R130A . Conclusion(s): These results demonstrate an inactivation of the NF-kB signaling cascade in mE6 expressing mouse keratinocytes. Interestingly, the evidence of increased nuclear IKKα motivated us to explore the impact of mE6 on c-Myc, in which we found to be significant. This prompts us to further investigate the signaling cascades of c-Myc and how it might promote SCC. Dependent on our findings, this could lead to possible drug therapies to reverse established infection.

Context: Human Papilloma Virus (HPV) is a double-stranded DNA virus that infects stratified squamous epithelium. HPV is associated with squamous cell carcinoma (SCC) formation in notable areas such as the cervix and oropharyngeal tissues. HPV oncoproteins E6 and E7 inhibit tumor suppressors p53 and pRB respectively and are the key drivers of carcinogenesis/cancer development. Given that HPV is species specific to humans, in vivo studies of its pathogenesis have been limited. Mus musculus papillomavirus type 1 (MmuPV1) can serve as an animal model of HPV since it causes infection at the same anatomical locations. Our results show that MmuPV1 E6 (mE6) alters IKK complex activity to downregulate the NF-κB signaling pathway, resulting in increased nuclear localization of IKKα. Recent literature suggests that nuclear IKKα contributes to SCC development by upregulating c-Myc expression. Consistent with this claim, we observed a corresponding upregulation of c-Myc in the presence of mE6. Objective and/or Hypothesis: To define the mechanism by which MmuPV1 E6 modulates

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2026 Research Recognition Day