These cells that repopulate and maintain GBM tumors after gross surgical resection are thought to be undifferentiated glioblastoma stem cells (GSCs, PMID: 29204831). They are known to be a major cause of recurrence after conventional therapy because GSCs possess self-renewal ability, aberrant multi-lineage differentiation, and resistance to chemotherapy and radiotherapy.  Recent reports have shown that not only can GSCs differentiate into progenitor and terminal cells, but their daughter cells can also de-differentiate back into GSCs depending on microenvironmental cues and adaptation to treatment. Alternate cell surface markers such as integrin α6, SSEA-1, A2B5 and CD44 could also be considered to enrich for GSC population (PMID: 29204831).
Related Pathway/CSCs feature