Background: Preventing the progression and recurrence of colorectal cancer (CRC) remains a clinical challenge due to its heterogeneity and drug resistance. This underscores the need to discover new targets and elucidate their cancer-promoting mechanisms. This study analyzed the cancer-promoting mechanisms of tryptophanyl-tRNA synthetase 1 (WARS1) in CRC.

Methods: Clinical data and RNA expression profiles of CRC patients in public databases were analyzed using bioinformatics to determine the expression of WARS1. A WARS1 knockdown assay was conducted with HCT116 and RKO cell lines to systematically assess the effects of WARS1 on CRC cell proliferation, migration, cell cycle, and apoptosis. These assessments employed reverse transcription-quantitative polymerase chain reaction (RT-qPCR), Western blotting, wound healing and transwell assays, flow cytometry, and xenograft tumor assays. Additionally, RNA sequencing and gene enrichment-based analysis were performed following WARS1 knockdown to detect gene expression changes and related pathways.

Results: WARS1 was overexpressed in CRC tissues (p < 0.05). Downregulation of WARS1 inhibited the growth and migration of RKO and HCT116 cell lines (p < 0.05). This inhibitory effect on tumor growth was also observed in xenografts in nude mice after WARS1 knockdown (p < 0.01). Flow cytometry revealed an increase in apoptosis and cell cycle arrest following WARS1 knockdown (p < 0.05). Transcriptome sequencing analysis showed that reduced expression of WARS1 activated the p53 signaling pathway and apoptosis while suppressing DNA replication and the cell cycle. The p53 transcriptional inhibitor pifithrin-α partially prevented the activation of caspase 3 and reduced the levels of c-poly-ADP-ribose polymerases 1 (PARP1) and cyclin-dependent kinase inhibitor 1A (CDKN1A).

Conclusion: WARS1 was highly expressed in CRC, and its low expression was identified as a risk factor for CRC progression and recurrence. The current findings provide a theoretical basis for the development of therapeutic agents targeting WARS1 and elucidate its mechanism in CRC progression.