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

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-1beta. Models of early-stage HPV infection (human keratinocytes expressing HPV16 E6 and E7) and models of established HPV-positive head and neck cancers (patient-derived xenografts, head and neck cancer cell lines) exhibited similar dysregulation of IL-1 pathway genes and suppressed responses to IL-1beta 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-1beta-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. This RNA-seq study in primary human forekin keratinocytes was to define genes that are differentially expressed in the presence or absence of HPV16 E6 and E7 oncoproteins, with and without treatment with the pro-inflammatory cytokine IL-1beta. mRNA profiles in primary HFK were generated for the following samples (# of replicates): untreated GFP/GFP (3), GFP/GFP treated with 0.5 ng/ml IL-1B for 3h (3), untreated HPV16 E6/E7 (3), HPV16 E6/E7 treated with 0.5 ng/ml IL-1B for 3h (3).