Combining anti-PVT1-104aa with anti-PD-L1 therapy suppressed CRC growth and increased CD4<sup>+</sup> and CD8<sup>+</sup> T cell infiltration in xenograft syngeneic tumour models and CRC tissues.<h4>Conclusions</h4>Our results uncover a pathogenic role of the PVT1-originated molecular species PVT1-104aa and suggest that targeting this pathway represents a promising therapeutic strategy for CRC treatment.<h4>Key points</h4>Circ-PVT1 is upregulated in CRC patients and encoded a novel protein: PVT1-104aa. This evidence concerns the gene CD8A and neoplasm.