Clinical relevance was analyzed with archived NSCLC samples and using datasets from the UCSC Xena database.<h4>Results</h4>LDOC1 interacts with histone H2B and H2Bub1 as well as with PSMA1 to promote their proteasomal degradation, thereby limiting global H2Bub1 levels. Here, PSMA1 is linked to non-small cell lung carcinoma.