Dataset Information

DCLK1 Monoclonal Antibody-Based CAR-T Cells as a Novel Treatment Strategy against Human Colorectal Cancers.

ABSTRACT: CAR-T (chimeric antigen receptor T cells) immunotherapy is effective in many hematological cancers; however, efficacy in solid tumors is disappointing. Doublecortin-like kinase 1 (DCLK1) labels tumor stem cells (TSCs) in genetic mouse models of colorectal cancer (CRC). Here, we describe a novel CAR-T targeting DCLK1 (CBT-511; with our proprietary DCLK1 single-chain antibody variable fragment) as a treatment strategy to eradicate CRC TSCs. The cell surface expression of DCLK1 and cytotoxicity of CBT-511 were assessed in CRC cells (HT29, HCT116, and LoVo). LoVo-derived tumor xenografts in NOD Scid gamma (NSGTM)mice were treated with CBT-511 or mock CAR-T cells. Adherent CRC cells express surface DCLK1 (two-dimensional, 2D). A 4.5-fold increase in surface DCLK1 was observed when HT29 cells were grown as spheroids (three-dimensional, 3D). CBT-511 induced cytotoxicity (2D; p < 0.0001), and increased Interferon gamma (IFN-γ) release in CRC cells (2D) compared to mock CAR-T (p < 0.0001). Moreover, an even greater increase in IFN-γ release was observed when cells were grown in 3D. CBT-511 reduced tumor growth by approximately 50 percent compared to mock CAR-T. These data suggest that CRC cells with increased clonogenic capacity express increased surface DCLK1. A DCLK1-targeted CAR-T can induce cytotoxicity in vitro and inhibit xenograft growth in vivo.

SUBMITTER: Sureban SM

PROVIDER: S-EPMC7016951 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundThe chimeric antigen receptor NK-92 (CAR NK-92) cell targeting the prostate-specific membrane antigen (PSMA) has shown antitumour effects in castration-resistant prostate cancer (CRPC). However, the expression changes of programmed death ligand 1 (PD-L1) and its mechanisms on CAR NK-92 and CRPC cells and the effect of the anti-PD-L1 monoclonal antibody (mAb) on PD-L1 expressed on CAR NK-92 cells remain unknown.MethodsHuman dendritic cells and CD8+ T cells were acquired from blood samples of healthy donors and cocultured with C4-2 cells. Changes in PD-L1 expression were detected by flow cytometry. Differential gene expressions were investigated by RNA sequence analysis, while the regulation of PD-L1 molecular signaling was explored using western blotting. In vitro cytotoxicity was evaluated using the Cell Counting Kit-8 assay and the bioluminescent intensity (BLI) of green fluorescent protein-labelled C4-2 cells. CRPC growth in vivo was monitored using callipers and BLI in male NOD/SCID mice subcutaneously injected with C4-2 cells and treated intravenously with anti-PD-L1/PD-1 mAb, CAR NK-92 or cocultured CD8+ T cells.ResultsSignificantly upregulated expression of PD-L1k was observed in cocultured C4-2 and CAR NK-92 cells. In addition, upregulation of PD-L1 expression was dependent on interferon-γ in C4-2 cells, while it was dependent on direct cell-to-cell interaction via the NK group 2 member D/ phosphatidylinositol 3-kinase/AKT pathway in CAR NK-92 cells. The anti-PD-L1 mAb directly acted on PD-L1 expressed on CAR NK-92 cells and augmented the cytotoxicity of CAR NK-92 cells against C4-2 and CRPC cells from one patient in vitro. Anti-PD-L1 mAb significantly enhanced the antitumour effect of CAR NK-92 cells against CRPC cells in vivo when compared to treatment with CAR NK-92 cells or combined with anti-PD-1 mAb in the absence or presence of cocultured CD8+ T cells.ConclusionCombined treatment with CAR NK-92 and anti-PD-L1 mAb improved the antitumour efficacy against CRPC, which is of extraordinary translational value in the clinical treatment of CRPC.

Dataset Information

DCLK1 Monoclonal Antibody-Based CAR-T Cells as a Novel Treatment Strategy against Human Colorectal Cancers.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets