CD44 and neoplasm: We have recently demonstrated the presence of three CSC subpopulations within moderately differentiated lip SCC (MDLSCC): a CD44+/SALL4+/NANOG+/pSTAT3+/SOX2+/OCT4− CSC sub-population within the tumor nests (TNs), a CD44+/SALL4+/NANOG+/pSTAT3+/SOX2+/OCT4− CSC subpopulation, and a CD44+/SALL4+/NANOG+/pSTAT3+/SOX2+/OCT4+ CSC subpopulation within the stroma, between the TNs (16).