We study the effects of neutrino spin-flips in the magnetic field, B(subscript AGN), of an active galactic nuclei (AGN) for high-energy neutrinos (E ≥ 10^6 GeV) originating from the AGN, induced by an interplay of a violation of the equivalence principle parameterized by △f and the twist in B(subscript AGN). We point out that a conversion effect may exist for △f ~ 10^(-34)(δm^2/10^(-5) eV^2) independent of the gravity mixing angle. Observational consequences for this conversion effect are discussed.