ALDH1A2 and neoplasm: In contrast, ALDH1A2 mRNA expression was strongly increased, in early steps of the TIC selection process (s1-s2) and remained elevated in later NS passages (s3-s4) in the I-type SK-N-Be2c cell line, as well as in the NB1 PDX tumor and the related NB1-C cell line (Fig. 1).