The present invention relates to a novel function of lysyl tRNA synthetase (KRS) which enhances tumor cell migration and affects cancer metastasis via KRSs interaction with laminin receptor (67LR) by its translocation to membrane. More particularly, the present invention relates to a method for modulating cancer metastasis or migration, which comprises regulating intracellular levels of KRS a composition for preventing or treating cancer use of expression vector for inhibiting the expression of KRS a method for preventing or treating cancer use of an agent for inhibiting an activity of KRS a method for screening an agent which modulates cancer metastasis or migration and a method for screening an agent which inhibits the interaction of KRS with 67LR, by said novel function. Thus, KRS can modulate cancer metastasis or migration and furthermore, can modulate intracellular metabolism related to 67LR. The interaction between KRS and 67LR can be used effectively in treating, preventing and/or diagnosing of various diseases or disorders related to the interaction.
