  We investigate a six-dimensional universal extra-dimensional model in the
extension of an effective neutrino mass operator. We derive the \beta-functions
and renormalization group equations for the Yukawa couplings, the Higgs
self-coupling, and the effecive neutrino mass operator in this model.
Especially, we focus on the renormalization group running of physical
parameters such as the Higgs self-coupling and the leptonic mixing angles. The
recent measurements of the Higgs boson mass by the ATLAS and CMS collaborations
at the LHC as well as the current three-flavor global fits of neutrino
oscillation data have been taken into account. We set a bound on the
six-dimensional model, using the vacuum stability criterion, that allows five
Kaluza-Klein modes only, which leads to a strong limit on the cutoff scale.
Furthermore, we find that the leptonic mixing angle \theta_{12} shows the most
sizable running, and that the running of the angles \theta_{13} and \theta_{23}
are negligible. Finally, it turns out that the findings in this six-dimensional
model are comparable with what is achieved in the corresponding
five-dimensional model, but the cutoff scale is significantly smaller, which
means that it could be detectable in a closer future.
