L1CAM and neoplasm: Neural cell adhesion molecule L1 (L1CAM, also termed L1), which is usually regarded as an important regulator in neural development and functions of adult brain [22, 23, 24, 25, 26, 27], was recently determined to be strongly associated with an aggressive tumor phenotype, high tumor grade, chemoresistance, metastasis, and poor patient prognosis in various tumors [28, 29, 30, 31, 32, 33, 34].