Insufficient information available. The provided PubMed abstracts do not contain relevant data about the PIR (pirin) gene on chromosome X. The abstracts discuss unrelated topics: post-isometric relaxation (PIR) therapy for temporomandibular disorders 1, immunological checkpoint inhibitor ILT4 in lung cancer 2, pregnancy-induced rhinitis (PIR) [PMID:23671891; 39], PIWI-interacting RNAs (piRNAs) in cancer including piR-2158 4, piR-823 as a cancer biomarker 5, piR-RCC in renal cell carcinoma 6, and Plasmodium interspersed repeat (pir) genes in malaria parasites 7. None of these abstracts address the human PIR gene, its transcriptional coregulatory function in NF-kappa-B signaling, its quercetin 2,3-dioxygenase activity, or its role in myeloid cell differentiation. To provide an accurate gene function summary with proper citations, peer-reviewed literature specifically investigating the human PIR/pirin protein would be required.