Carreno, B. M. | Search bioRxiv

bioRxiv2026

Therapeutic scheduling of WEE1 inhibition preserves T cell function and promotes immune control of HPV⁺ tumors

Human papillomavirus-associated oropharyngeal squamous cell carcinoma (HPV OPC) is driven by viral E6 and E7 oncoproteins, which disrupt G1 checkpoint control and impose selective dependency on WEE1-mediated G2/M regulation. While this vulnerability confers sensitivity to WEE1 inhibition, its immunologic consequences remain poorly defined, and the challenge of eliciting antitumor immunity without compromising immune fitness has limited clinical translation. Here, we show that WEE1 inhibition elicits durable antitumor immunity in immunocompetent models of HPV OPC. Using murine and human preclinical systems, we demonstrate that the WEE1 inhibitor azenosertib (ZN-c3) mediates tumor control through both cell-autonomous cytotoxicity and immune-dependent mechanisms requiring T cells and conventional dendritic cells. Mechanistically, HPV tumor cells are deficient in STING signaling and fail to mount canonical type I interferon responses. Instead, tumor cell-intrinsic cGAS drives immune activation through STING-competent host cells within the tumor microenvironment, revealing a non-cell-autonomous relay that circumvents viral immune evasion. Intermittent WEE1 inhibition preserves T cell fitness while maintaining antitumor efficacy, and mice achieving complete responses develop immunologic memory capable of rejecting tumor rechallenge. These findings establish intermittent WEE1 inhibition as an immune-permissive therapeutic strategy that enables antigen-specific T cell responses in HPV-driven malignancies and provides a mechanistic rationale for combination with immunotherapy.

cancer biology↗

bioRxiv2026

Tumor-to-endothelium mitochondrial transfer licenses endothelial cells for CD8+ T cell recognition via mitochondrial neoantigen presentation

Renal cell carcinoma (RCC) frequently exhibits resistance to immune checkpoint blockade, highlighting the need for strategies that enhance tumor-specific T cell priming and improve immune access to the tumor microenvironment. Here we show that vaccination targeting tumor-associated mitochondrial antigens (TAMAs), derived from tumor-specific mitochondrial DNA (mtDNA) missense mutations, synergizes with PD-1/PD-L1 blockade to overcome checkpoint refractoriness in the RENCA RCC model. TAMAs vaccination elicits antigen-specific T cell responses, increases intratumoral CD8+ T cell infiltration, and reduces immunosuppressive myeloid populations, resulting in delayed tumor progression and improved survival when combined with checkpoint inhibition. In parallel, TAMAs + checkpoint blockade induces vascular remodeling characterized by increased pericyte coverage, reduced vascular leakage, improved perfusion and reduced hypoxia. Mechanistically, vascular remodeling is driven by CD8+ T cell-dependent, IFN{gamma}-associated immune activity and is associated with endothelial apoptosis and diminished intratumoral CD31 signal. We further identify tumor-to-endothelium mitochondrial transfer as a mechanism linking mitochondrial neoantigens to the tumor vascular compartment: tumor-derived mitochondria enter human and mouse endothelial cells in vitro and in vivo, and tumor-associated mtDNA mutations are detectable in endothelial fractions from murine tumors and human RCC specimens. Human endothelial cells can present mitochondrial neoantigens via MHC class I and become targets of TAMAs-specific CD8+ T cell cytotoxicity, including following mitochondrial acquisition from tumor cells. Together, these findings establish mitochondrial neoantigen immunity as a tractable approach to enhance checkpoint responses and reveal mitochondrial transfer as an antigenic bridge that expands immune targeting to the tumor vasculature.

cancer biology↗