Tumor and permissive host cells

Tumor / permissive host cells refers to a cellular population, primarily malignant cells, that supports the entry, replication, and spread of therapeutic agents such as oncolytic viruses (Nature Reviews Cancer, 2021). A permissive cell is defined by its ability to provide the necessary molecular machinery for viral biosynthesis while lacking effective innate antiviral defenses, such as the interferon (IFN) signaling pathway (Journal of Virology, 2018). In many cancers, these antiviral pathways are naturally attenuated to facilitate rapid cell division, making the tumor cells selectively vulnerable to viral infection compared to healthy, non-permissive cells (Molecular Therapy, 2020). Drugs targeting these cells, such as Talimogene laherparepvec (T-VEC), utilize this selectivity to induce direct oncolysis and stimulate a systemic anti-tumor immune response (FDA Label, Imlygic). This target concept is central to the development of viral-based gene therapies and immunotherapies that exploit the unique physiological landscape of the tumor microenvironment (Cell, 2019). While not a single molecular entity, this cellular target is the focus of advanced biologics designed to exploit the physiological differences between malignant and healthy tissues.

Other names

Malignant cellsPermissive cellsCancer cellsHost cellsTumor microenvironment cells

Selective viral replication within permissive malignant cells leads to direct cell lysis (oncolysis) and the release of tumor-derived antigens and damage-associated molecular patterns (DAMPs), which recruit and activate the host immune system against the cancer (Nature Reviews Cancer, 2021).