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bioRxiv · 10.1101/2022.08.25.505364

Systematic analysis of IL-1 cytokine signaling suppression by high-risk HPV oncoproteins

Abstract

Human papillomavirus (HPV) E6 and E7 oncoproteins are expressed at all stages of HPV-mediated carcinogenesis and are essential drivers of cancers caused by high-risk HPV. Some of the activities of HPV E6 and E7, such as their interactions with host cellular tumor suppressors, have been characterized extensively. There is less information about how high-risk HPV E6 and E7 alter cellular responses to cytokines that are present in HPV-infected tissues and are an important component of the tumor microenvironment. We used several models of HPV oncoprotein activity to assess how E6 and E7 alter the cellular response to the pro-inflammatory cytokine IL-1{beta}. Models of early-stage HPV infection and of established HPV-positive head and neck cancers exhibited similar dysregulation of IL-1 pathway genes and suppressed transcriptional responses to IL-1{beta} treatment. Such overlap in cell responses supports that changes induced by HPV E6 and E7 early in infection could persist and contribute to a dysregulated immune environment throughout carcinogenesis. HPV E6 and E7 also drove the upregulation of several suppressors of IL-1 cytokine signaling, including SIGIRR, both in primary keratinocytes and in cancer cells. SIGIRR knockout was insufficient to increase IL-1{beta}-dependent gene expression in the presence of HPV16 E6 and E7, suggesting that multiple suppressors of IL-1 signaling contribute to dampened IL-1 responses in HPV16-positive cells. IMPORTANCEHuman papillomavirus (HPV) infection is responsible for nearly 5% of the worldwide cancer burden. HPV-positive tumors develop over years to decades in tissues that are subject to frequent stimulation by pro-inflammatory cytokines. However, the effects of HPV oncoproteins on the cellular response to cytokine stimulation are not well defined. We analyzed IL-1 cytokine signaling in several models of HPV biology and disease. We found that HPV16 E6 and E7 oncoproteins mediate a broad and potent suppression of cellular responses to IL-1{beta} in models of both early and late stages of carcinogenesis. Our data provide a resource for future investigation of IL-1 signaling in HPV-positive cells and cancers.

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BibTeXRIS

Castagnino, P., Kim, H. W., Lam, L. K. M., Basu, D., White, E. A.. 2022-08-26. Systematic analysis of IL-1 cytokine signaling suppression by high-risk HPV oncoproteins. https://doi.org/10.1101/2022.08.25.505364

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