The present invention relates to an anti-cancer composition having anti-proliferative and/or inhibitory effects specifically targeted at malignant cells, which comprises a filtrated bacteria-free and/or yeast-free liquid extract of initial fermentative kefir in association with a pharmaceutically acceptable carrier. The present invention also relates to a method of inhibiting proliferation of malignant cells in patient, which comprises administering an effective amount of a filtrated bacteria-free and/or yeast-free liquid extract of initial fermentative kefir. The present invention also relates to a prophylactic composition having neutraceutical properties, which comprises a filtrated bacteria-free and/or yeast-free liquid extract of initial fermentative kefir in association with a pharmaceutically acceptable carrier.
