  We have studied the effects of nonlinear scale evolution of the parton
distribution functions to charm production in $pp$ collisions at center-of-mass
energies of 5.5, 8.8 and 14 TeV. We find that the differential charm cross
section can be enhanced up to a factor of 4-5 at low $p_T$. The enhancement is
quite sensitive to the charm quark mass and the renormalization/factorization
scales.
