PRKRIP1, A Splicing Complex Factor, Is a Marker of Poor Prognosis in Colorectal Cancer

Background/Aim: Alternative splicing plays a vital role in cancer development and progression. The splicing C complex is involved in alternative splicing. However, the role of PRKR-interacting protein 1 (PRKRIP1), a component of the splicing C complex, in colorectal cancer (CRC) remains unclear. This study aimed to determine the clinicopathological, biological and prognostic significance of PRKRIP1 expression in CRC. Materials and Methods: We used a bioinformatics approach to screen for oncogenes using The Cancer Genome Atlas (TCGA) and Cancer Cell Line Encyclopedia (CCLE) datasets and identified PRKRIP1 as a driver gene on chromosome 7q. The mRNA expression of PRKRIP1 was measured using reverse transcription-quantitative PCR in 165 surgically resected CRC samples in our hospital, and its localization was determined using immunohistochemical staining. Gene Set Enrichment Analysis (GSEA) was performed using TCGA dataset. Results: High PRKRIP1 expression was significantly associated with poor prognosis in both the samples and TCGA dataset. A positive correlation was observed between copy number variation and PRKRIP1 expression in TCGA and CCLE datasets, and the frequency of PRKRIP1 mutations was less than 5%. Immunohistochemistry revealed that PRKRIP1 was located in the cytoplasm of tumor cells. GSEA revealed that PRKRIP1 expression was correlated with apoptosis-related gene sets. Conclusion: PRKRIP1 overexpression may be a poor prognostic biomarker for CRC. Although it is known that PRKRIP1, a spliceosome factor, is essential for splicing, we now revealed the way by which its expression accelerates CRC progression.