TP53INP2 modulates the malignant progression of colorectal cancer by reducing the inactive form of β-catenin

TP53INP2 (tumor protein p53-inducible nuclear protein 2), known as an autophagy protein, is essential for regulating transcription and starvation-induced autophagy, which plays a crucial role in the oncogenesis and progression of various cancers. The present study aims to investigate the expression pattern, function and prognostic value of TP53INP2 in colorectal cancer (CRC). Here, we report that low expression of TP53INP2 correlates with poor survival in CRC patients. TP53INP2 was significantly downregulated in CRC tissues compared with adjacent tissues. As the malignancy of CRC progresses, the expression level of TP53INP2 gradually decreased. Knockdown of TP53INP2 promoted CRC cell proliferation and tumor growth in mice. Mechanistically, TP53INP2 deficiency decreased phosphorylation of beta-catenin on S33, S37, and T41, resulting in increased accumulation of beta-catenin and enhanced nuclear translocation and transcriptional activity. Moreover, we further demonstrated that TP53INP2 sequestered TIM50, thereby inhibiting its activation of beta-catenin. Taken together, our findings indicate that the downregulation of TP53INP2 promotes CRC progression by activating beta-catenin and suggest that TP53INP2 may be a candidate therapeutic target for CRC.

Automated summary

This study found that low expression of TP53INP2 is associated with poor survival in colorectal cancer (CRC) patients. As the malignancy of CRC progresses, TP53INP2 expression gradually decreases. Knockdown of TP53INP2 promotes CRC cell proliferation and tumor growth. Mechanistically, TP53INP2 deficiency decreases phosphorylation of beta-catenin, leading to increased accumulation and enhanced nuclear translocation and transcriptional activity. Additionally, TP53INP2 sequesters TIM50, inhibiting its activation of beta-catenin. In conclusion, downregulation of TP53INP2 promotes CRC progression by activating beta-catenin.