Journal: Journal for Immunotherapy of Cancer
Article Title: CD70 as an actionable immunotherapeutic target in recurrent glioblastoma and its microenvironment
doi: 10.1136/jitc-2021-003289
Figure Lengend Snippet: CD70 is a dedicated player in GBM maintenance and tumor formation. (A) GBM CSCs were sorted into positive and negative populations and proliferation was assessed by PrestoBlue assay (B) Limiting dilution analyses of CD70 positive and negative cells in pGBM (GBM8) and rGBM (BT241). (C) Cell surface CD70 expression after shRNA knockdown in three CD70 HIGH GBM lines, as assessed by flow cytometry. (D) Silencing of CD70 expression by shRNA (shCD70) knockdown and sphere formation ability was assessed compared with shGFP (control shRNA). (E–I) Immunocompromised mice (NSG, a minimum of six mice per condition) were intracranially injected with shGFP or shCD70 CSCs. (E, F) Tumor area of CD70-silenced CSCs compared with control knockdown CSCs was measured using formalin-fixed, H&E-stained mouse brain slices (right, representative image). (G, H) Kaplan-Meier survival curves comparing mice engrafted with shCD70 CSCs compared with shGFP CSCs. The two remaining BT241 shCD70 mice at the end of experiment showed an absence of tumor by H&E staining at experimental endpoint (data not shown). (I) MRI images representative of xenografts from shGFP and shCD70 transduced GBM CSC line BT241. Images on the right are control images of normal mouse brain. (*P<0.05; **p<0.01; ***p<0.001; ****p<0.0001). CSCs, cancer stem cells; GBM, glioblastoma; pGBM, primary GBM; NSG, NOD/SCID gamma; shRNA, short hairpin RNA.
Article Snippet: Guide RNAs (gRNAs) targeting AAVS1 (5’-GGGGCCACTAGGGACAGGAT-3’) and CD70 (A: 5’- GCTGAGCCTGTGCGAAGCGC-3’; B: 5’-ATGGGACCAAAGCAGCCCGC-3’ were obtained from TKOv3 and cloned into a single-gRNA lentiCRISPRv2 construct (Addgene 52961).
Techniques: Prestoblue Assay, Expressing, shRNA, Knockdown, Flow Cytometry, Control, Injection, Staining