The <i>FAM</i> gene family and its bridging of male infertility and oncogenic signaling mechanisms: A comprehensive review

The family with sequence similarity (FAM) gene family links pathological mechanisms of male infertility and oncogenesis. This review focuses on five key FAM members (FAM71D, FAM46C, FAM170A, FAM83D, and FAM172A), which were selected based on: clinical relevance (FAM83D as a breast cancer prognostic biomarker, hazard ratio, 1.29, p<0.05; FAM71D homozygous mutation c.440G>A associated with asthenoteratospermia); adequate experimental validation (in vitro assays, in vivo models, and clinical samples-for example, FAM170A knockout mice exhibit male infertility, with reduced transcription observed in patients); and recent impact (≥30 PubMed-indexed studies within 5 years and clearly defined mechanisms). In reproduction, FAM71D maintains sperm motility via calmodulin- plasma membrane Ca2+-ATPase (PMCA)- Ca2+ signaling, FAM46C anchors the sperm head-flagellum junction, and FAM170A regulates chromatin remodeling through ubiquitin- specific protease 7 (USP7)-mediated H2B deubiquitination. In oncology, FAM83D activates mitogen-activated protein kinase kinase/extracellular signal-regulated kinase signaling to drive hepatocellular carcinoma, whereas FAM172A dysregulates p38 mitogen-activated protein kinase in thyroid cancer. Translational advances include FAM83B nanodetection, the Fam20C inhibitor FL-1607 (IC50=2.1 μM), and clustered regularly interspaced short palindromic repeats (CRISPR)-corrected FAM170A. Cross-species functional divergence remains a challenge. FAM genes enable novel diagnostics and targeted therapies for reproductive and oncological care, with near-term clinical applications in personalized assisted reproductive technology and cancer precision medicine.