IGKV1D-22 and neoplasm: A recent study demonstrated that low concentrations of S100A8/A9, namely, 5 or 10 μg/mL, significantly promoted tumor cell proliferation of human breast cancers and human neuroblastoma cell lines; when the concentration of S100A8/A9 was increased to 25 μg/mL, however, the promoting effect disappeared [37].