Molinolo, A. A. | bioRxiv Science

bioRxiv2023

Direct reprogramming of oral epithelial progenitor cells to cancer stem cells at single cell resolution in vivo

Tumor initiation represents the first step in tumorigenesis during which normal progenitor cells undergo cell fate transition to cancer. Capturing this process as it occurs in vivo, however, remains elusive. Here we employ spatiotemporally controlled oncogene activation and tumor suppressor inhibition together with multiomics to unveil the processes underlying oral epithelial progenitor cell reprogramming into tumor initiating cells (TIC) at single cell resolution. TIC displayed a distinct stem-like state, defined by aberrant proliferative, hypoxic, squamous differentiation, and partial epithelial to mesenchymal (pEMT) invasive gene programs. YAP-mediated TIC programs included the activation of oncogenic transcriptional networks and mTOR signaling, and the recruitment of myeloid cells to the invasive front contributing to tumor infiltration. TIC transcriptional programs are conserved in human head and neck cancer and associated with poor patient survival. These findings illuminate processes underlying cancer initiation at single cell resolution, and identify candidate targets for early cancer detection and prevention.

cancer biology↗

bioRxiv2022

Lymphatic-Preserving Treatment Sequencing with Immune Checkpoint Inhibition Unleashes cDC1-Dependent Antitumor Immunity in HNSCC

Immune checkpoint inhibition (ICI) with anti-CTLA-4 and anti-PD-1 has revolutionized oncology; however, response rates remain limited in most cancer types, highlighting the need for more effective immune oncology (IO) treatment strategies. Paradoxically, head and neck squamous cell carcinoma (HNSCC), which bears a mutational burden and immune infiltrate commensurate with cancers that respond robustly to ICI, has demonstrated no response to anti- CTLA-4 in any setting or to anti-PD-1 for locally-advanced disease. Scrutiny of the landmark clinical trials defining current IO treatments in HNSCC reveals that recruited patients necessarily received regional ablative therapies per standard of care, prompting us to hypothesize that standard therapies, which by design ablate locoregional lymphatics, may compromise host immunity and the tumor response to ICI. To address this, we employed tobacco-signature HNSCC murine models in which we mapped tumor-draining lymphatics and developed models for regional lymphablation with surgery or radiation. Remarkably, we found that lymphablation eliminates the tumor ICI response, significantly worsening overall survival and repolarizing the tumor- and peripheral-immune compartments. Mechanistically, within tumor-draining lymphatics, we observed an upregulation of cDC1 cells and IFN-I signaling, showed that both are necessary for the ICI response and lost with lymphablation. Ultimately, we defined rational IO sequences that mobilize peripheral immunity, achieve optimal tumor responses, confer durable immunity and control regional lymphatic metastasis. In sum, we provide a mechanistic understanding of how standard regional, lymphablative therapies impact the response to ICI, which affords insights that can be applied to define rational, lymphatic-preserving IO treatment sequences for cancer. One Sentence SummaryDespite the promise of immune checkpoint inhibition, therapeutic responses remain limited, raising the possibility that standard of care treatments delivered in concert may compromise the tumor response; here, we provide a mechanistic understanding of how standard oncologic therapies targeting regional lymphatics impact the tumor response to immune-oncology therapy in order to define rational treatment sequences that mobilize systemic antitumor immunity, achieve optimal tumor responses, confer durable antitumor immunity, and control regional metastatic disease. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=107 SRC="FIGDIR/small/478744v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@542d71org.highwire.dtl.DTLVardef@737ad0org.highwire.dtl.DTLVardef@183f519org.highwire.dtl.DTLVardef@505ce2_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2019

Novel syngeneic animal model of tobacco-associated oral cancer reveals the activity of in situ anti-CTLA-4

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Tobacco use is the main risk factor for HNSCC, and tobacco-associated HNSCCs have poor prognosis and response to available treatments. Recently approved anti-PD-1 immune checkpoint inhibitors showed limited activity ([≤]20%) in HNSCC, highlighting the need to identify new therapeutic options. For this, mouse models that accurately reflect the complexity of the HNSCC mutational landscape and tumor immune environment are urgently needed. Here, we report the first mouse HNSCC model system that recapitulates the human tobacco-related HNSCC mutanome, in which tumors grow when implanted in the tongue of immunocompetent mice. These HNSCC lesions have similar immune infiltration and response rates to anti-PD-1 ([≤]20%) immunotherapy as human HNSCCs. Remarkably, we found that >70% of HNSCC lesions respond to intratumoral anti-CTLA-4. This syngeneic HNSCC mouse model provides a platform for the development of novel immunotherapeutic options for HNSCC.

cancer biology↗