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

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.

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.

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.

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.