C1QTNF8 (C1q and TNF related 8) is a secreted adipokine belonging to the C1q/TNF-related protein (CTRP) family that functions as a ligand for the G protein-coupled receptor RXFP1 1. As a member of the CTRP family, C1QTNF8 bridges inflammatory and metabolic pathways 2. The protein is expressed predominantly in lung and testis tissues and can form both homotrimeric and heteromeric complexes with other C1q/TNF family members 3. C1QTNF8 promotes cell motility through RXFP1 activation, engaging the PI3 kinase and PKC signaling pathways 4. In glioblastoma, the CTRP8-RXFP1 axis activates JAK3-STAT3 signaling, driving Cdc42-dependent actin remodeling and enhanced cell motility 5. C1QTNF8 also confers chemotherapy resistance by protecting glioblastoma cells from temozolomide-induced DNA damage through RXFP1-STAT3-dependent upregulation of base excision repair and anti-apoptotic factors 6. In prostate cancer, CTRP8 marks a tryptase+ mast cell subpopulation correlating with biochemical recurrence 1. Loss-of-function variants in C1QTNF8 show apparent recessive effects on serum magnesium levels in humans 7. Recent evidence links RXFP1 variants to hereditary periodic fever syndromes, implicating the CTRP8-RXFP1 axis in immune regulation 8.