Disclosed herein are methods of increasing numbers of monocytes to a tumor or cancer metastasis site in a subject. Non-limiting embodiments include administering or using a Nur77 polypeptide or subsequence thereof； a Nur77 agonist； a CX3CR1 agonist； CD14+ CD16+ monocytes and/or CD14dimCD16+(CD115+CD11b+GR1−(Ly6C−)) monocytes； CD14+CD16+ monocytes and/or CD14dimCD16+(CD115+CD11b+GR1−(Ly6C−)) monocytes contacted with a Nur77 agonist or contacted with a CX3CR1 agonist. Also disclosed herein are methods of increasing, stimulating, activating or promoting monocyte migration to or mobilization against a tumor or cancer metastasis in a subject. Non-limiting embodiments include administering a Nur77 polypeptide or sub-sequence thereof； a Nur77 agonist； a CX3CR1 agonist； CD14+ CD16+ monocytes and/or CD14dimCD16+(CD115+CD11b+GR1− (Ly6C−)) monocytes； or CD14+CD16+ monocytes and/or CD14dimCD16+(CD115+CD11b+GR1−(Ly6C−)) monocytes contacted with a Nur77 agonist or contacted with a CX3CR1 agonist.
