Use of a composition for breast cancer diagnosis, said composition comprising (a) (i) at least one polynucleotide consisting of a sequence that is the same as, or complementary to, a microRNA (miRNA) selected from the group consisting of hsa-miR-126, hsa-miR-24, and hsa-miR-15a in a vesicle, or a fragment of the microRNA having a length of 5 to 22 consecutive nts in a vesicle, and (ii) a material specifically binding to the vesicle, wherein the material specifically binding to the vesicle is a material capable of binding to a surface protein and wherein the surface protein is CD83; or (b) (i) - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-126 in a vesicle, or a fragment of hsa-miR-126 having a length of 5 to 22 consecutive nts in a vesicle, - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-19b in a vesicle, or a fragment of hsa-miR-19b having a length of 5 to 22 consecutive nts in a vesicle, - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-23a in a vesicle, or a fragment of hsa-miR-23a having a length of 5 to 22 consecutive nts in a vesicle, and - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-24 in a vesicle, or a fragment of hsa-miR-24 having a length of 5 to 22 consecutive nts in a vesicle, and (ii) a material specifically binding to the vesicle, wherein the material specifically binding to the vesicle is a material capable of binding to a surface protein and wherein the surface protein is CD83; or (c) (i) at least one polynucleotide consisting of a sequence that is the same as, or complementary to, a miRNA selected from the group consisting of hsa-miR-103, hsa-miR-142-3p, hsa-miR-144, hsa-miR-15a, hsa-miR-185, and hsa-miR-93 in a vesicle, or a fragment of the microRNA having a length of 5 to 22 consecutive nts in a vesicle, (ii) a material specifically binding to the vesicle, wherein the material specifically binding to the vesicle is a material capable of binding to a surface protein and wherein the surface protein is CD83, and (iii) a material capable of specifically binding to an integrin β protein. (a) (i) at least one polynucleotide consisting of a sequence that is the same as, or complementary to, a microRNA (miRNA) selected from the group consisting of hsa-miR-126, hsa-miR-24, and hsa-miR-15a in a vesicle, or a fragment of the microRNA having a length of 5 to 22 consecutive nts in a vesicle, and (ii) a material specifically binding to the vesicle, wherein the material specifically binding to the vesicle is a material capable of binding to a surface protein and wherein the surface protein is CD83; or (b) (i) - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-126 in a vesicle, or a fragment of hsa-miR-126 having a length of 5 to 22 consecutive nts in a vesicle, - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-19b in a vesicle, or a fragment of hsa-miR-19b having a length of 5 to 22 consecutive nts in a vesicle, - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-23a in a vesicle, or a fragment of hsa-miR-23a having a length of 5 to 22 consecutive nts in a vesicle, and - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-24 in a vesicle, or a fragment of hsa-miR-24 having a length of 5 to 22 consecutive nts in a vesicle, and (ii) a material specifically binding to the vesicle, wherein the material specifically binding to the vesicle is a material capable of binding to a surface protein and wherein the surface protein is CD83; or - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-19b in a vesicle, or a fragment of hsa-miR-19b having a length of 5 to 22 consecutive nts in a vesicle, - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-23a in a vesicle, or a fragment of hsa-miR-23a having a length of 5 to 22 consecutive nts in a vesicle, and - a polynucleotide consisting of a sequence that is the same as, or complementary to hsa-miR-24 in a vesicle, or a fragment of hsa-miR-24 having a length of 5 to 22 consecutive nts in a vesicle, and (ii) a material specifically binding to the vesicle, wherein the material specifically binding to the vesicle is a material capable of binding to a surface protein and wherein the surface protein is CD83; or (c) (i) at least one polynucleotide consisting of a sequence that is the same as, or complementary to, a miRNA selected from the group consisting of hsa-miR-103, hsa-miR-142-3p, hsa-miR-144, hsa-miR-15a, hsa-miR-185, and hsa-miR-93 in a vesicle, or a fragment of the microRNA having a length of 5 to 22 consecutive nts in a vesicle, (ii) a material specifically binding to the vesicle, wherein the material specifically binding to the vesicle is a material capable of binding to a surface protein and wherein the surface protein is CD83, and (iii) a material capable of specifically binding to an integrin β protein.