  Charm production in pp collisions is considered in the framework of
perturbative QCD. The values of two parameters, the charm quark mass $m_c$ and
the QCD scale mu^2, are determined from the comparison of the theoretical
calculations with experimental data. The RHIC data on charm and beauty
production are compared with the k_T-factorization approach predictions and
with standard NLO QCD. The calculated results underestimate the STAR
Collaboration data. The role of possible nuclear effects is discussed. The
predictions for LHC energies are also given.
