Human Papillomavirus type 18 (HPV-18) E7 is a high-risk viral oncoprotein central to cervical and other HPV-associated cancers. This ~100 amino acid protein drives malignant transformation by binding and inactivating retinoblastoma (pRb) via its LXCXE motif, releasing E2F transcription factors to trigger uncontrolled cell cycle progression. Its zinc-binding CR3 domain promotes dimerization and interactions with host regulators, including components of chromatin remodeling and Hippo signaling. Through degradation of PTPN14 and modulation of YAP1, HPV-18 E7 enhances proliferation, invasion, and impaired differentiation. Catalina’s HPV-18 E7 antibodies are rigorously validated reagents for research in virology, cancer research, molecular pathology, and vaccine development.