Human Papillomavirus type 16 (HPV-16) E7 is a key viral oncoprotein driving malignant transformation in cervical and head-and-neck cancers. Through its LXCXE motif, E7 binds and inactivates retinoblastoma (pRb), releasing E2F transcription factors to promote uncontrolled S-phase entry. Its CR3 zinc-binding domain supports dimerization and critical protein interactions that reprogram host transcription, epigenetics, and immune responses. Abundant E7 mRNA expression in HPV-positive tumors underscores its diagnostic and therapeutic relevance, though protein detection remains technically challenging. Catalina’s HPV-16 E7 antibodies are rigorously validated for sensitive and specific detection of this central oncogenic driver. These antibodies enable accurate detection of HPV-driven malignancies and support translational research in virology, cancer research, molecular pathology, and diagnostic development.