Tackling cancer heterogeneity with systemically delivered oncolytic adenoviruses transcriptionally targeted with hybrid promoters.

Tumor escape driven by cancer heterogeneity is a hallmark of human malignancies. Oncolytic adenoviruses (OAds) are transcriptionally targeted to selectively replicate in cancer cells through the use of tumor-specific promoters (TSPs). The aim of our study was to establish whether we can tackle cancer heterogeneity with OAds transcriptionally targeted with hybrid TSPs (hTSPs). Following a comprehensive bioinformatic and molecular screening process, we identified the A33 and vWA2 promoters (Prs) as optimal candidates to combine them to construct an hTSP to drive the replication of a novel OAd named AR2015. To validate its efficacy, we evaluated AR2015 in various human colorectal cancer (CRC) cell lines, patient-derived cells, and nude mouse models and compared it with two OAds driven by single TSPs (either A33-Pr or vWA2-Pr). AR2015 exhibited efficient replication in both A33-positive and vWA2-positive CRC cell lines, effectively broadening the oncolytic spectrum and overcoming the limitations of single-Pr OAds. Systemic administration of AR2015 significantly inhibited the growth of CRC-derived liver metastases expressing A33 and vWA2, with further therapeutic benefit observed in combination with oxaliplatin. These findings provide proof of concept for addressing tumor heterogeneity through transcriptionally targeted OAds driven by hTSPs.