MS4A1 and precursor B-cell acute lymphoblastic leukemia: <i>NONO</i>, a non-POU domain-containing octamer-binding protein implicated in several cancers, regulates CD20 surface expression.<h4>Methods</h4>To explore factors associated with heterogeneous CD20 expression, we quantified <i>MS4A1</i> transcript levels, profiled <i>MS4A1</i> messenger RNA (mRNA) isoforms, and analyzed <i>NONO</i> mRNA in pediatric B-ALL samples.