PSMB10 and neuroblastoma: Differences in APM component expression detected in primary NB cells vs NB cell lines (such as for example LMP10 expression in the latter but not the former cells, and Erp57 expression in the former but not the latter cells) may be related to the different sensitivity of immunohistochemistry vs flow cytometry and/or to changes acquired by primary NB cells during their transformation in immortal cell lines or later on due to adaption to culture conditions.