POLR2J3 encodes the RNA polymerase II subunit J3 (hRPB11), a core component of RNA polymerase II responsible for transcribing DNA into RNA 1. As part of the mobile element architecture of Pol II, POLR2J3 contributes to the basal transcription machinery that synthesizes mRNA precursors and functional non-coding RNAs. The gene is one of four POLR2J family members on chromosome 7, capable of generating multiple hRPB11 isoforms through alternative splicing 1. Clinically, POLR2J3 has emerged as a metastasis-related prognostic biomarker in laryngeal squamous cell carcinoma (LSCC), with significantly elevated expression in metastatic tissues compared to non-metastatic tissues 2. Additionally, POLR2J3 exhibits race-specific transcriptional differences in colon cancer, showing consistent differential expression across disease stages in Black versus white patients and contributing to a five-gene signature predictive of racial disparities in cancer outcomes 3. In colorectal serrated lesions, POLR2J3 expression is reciprocally regulated by miRNA-5787, suggesting involvement in early tumorigenesis pathways 4. These findings indicate POLR2J3's potential value as a biomarker for cancer prognosis and racial differences in tumor biology.