In addition to exosomal markers proteins, the cargo of NB exosomes contains GD2 and proteins involved in tumor progression such as CD147 (basigin, aka extracellular matrix metalloproteinase inducer (EMMPRIN)), a transmembrane protein involved in invasion and metastasis, and CD276/B7-H3, an immune checkpoint protein that protects NB cells from attack by NK cells [82,83]. Here, CD276 is linked to neoplasm.