IGFBP6 and glioblastoma: Consistent with our data, it has been reported that administration of exogenous IGFBP6 plays a tumor suppressive role in PT-resistant, but not PT-sensitive, EOC cells (Piscazzi et al, 2022) and that IGFBP6 expression is reduced in chemo-resistant glioblastoma (Oliva et al, 2018).