Tumor cells permissive for vaccinia replication

Tumor cells permissive for vaccinia replication refers to a specific subset of malignant cells characterized by their susceptibility to infection, replication, and subsequent destruction by oncolytic vaccinia viruses. This permissiveness is primarily driven by common oncogenic alterations, such as the activation of the Ras/MAPK pathway and the overexpression of growth factor receptors like EGFR, which provide the necessary cellular machinery for viral protein synthesis (PubMed: 23403424). Furthermore, many cancer cells possess defects in the Type I interferon (IFN) signaling pathway, which normally serves as a primary defense against viral infection, thereby allowing the virus to replicate unchecked within the tumor while being cleared by healthy cells (Nature Reviews Cancer: 10.1038/nrc2607). Therapeutic strategies using oncolytic vaccinia viruses, such as Pexastimogene devacirepvec (Pexa-Vec), leverage this permissiveness to induce direct viral oncolysis and stimulate a systemic immune response against the cancer. While not a single molecular receptor, this cellular phenotype serves as the functional target for viral-based immunotherapies. The selectivity for these cells minimizes damage to healthy tissues, which typically maintain intact antiviral pathways that suppress viral replication. The resulting oncolysis releases tumor-associated antigens and pro-inflammatory cytokines, transforming the tumor microenvironment to stimulate a systemic anti-tumor immune response (Journal for ImmunoTherapy of Cancer: 10.1186/s40425-017-0232-3).

Other names

Permissive tumor cellsVaccinia-susceptible cancer cellsOncolytic vaccinia virus target cellsSusceptible malignant cells

Selective viral entry and replication within permissive malignant cells leading to direct oncolysis and the subsequent induction of a systemic anti-tumor immune response through the release of tumor-associated antigens and cytokines.