The coenzyme A precursor pantethine restrains sarcoma growth through promotion of type 1 immunity

The tumor microenvironment is a dynamic network of stromal, cancer and immune cells that interact and compete for resources. Mitochondria play an essential role in the control of metabolic plasticity and contribute to tumor progression and immune cell functionality. We previously identified the Vanin1 pathway as a tumor suppressor of sarcoma development via vitamin B5 and coenzyme A regeneration. Using an aggressive sarcoma cell line that lacks Vnn1 expression, we showed that administration of pantethine, a vitamin B5 precursor, impairs tumor growth in immunocompetent mice. Pantethine boosts anti-tumor type 1 immunity including polarization of myeloid and dendritic cells towards enhanced IFN?-driven antigen presentation pathways and improved development of hypermetabolic effector CD8+ T cells endowed with potential anti-tumor activity. At later stages of treatment, the effect of pantethine is limited by the development of immune cell exhaustion. Nevertheless, its activity is comparable to that of anti-PD1 treatment in sensitive tumors. In humans, VNN1 expression correlates with improved survival and immune cell infiltration in soft tissue sarcomas but not osteosarcomas. Pantethine could be a potential therapeutic immunoadjuvant for the development of anti-tumor immunity. Overall design: 1 subcutaneous MCA205 tumor from D20 and 1 tumor from D28 from PBS- or Pant-treated C57BL/6 mice were harvested, dissociated and processed as mentioned in the extract protocol section. CD45+ cells were enriched by cell-sorting and each condition where discriminated by HTO staining with TotalSeqB before beeing pooled for cDNA libraries construction and sequencing