Project description:Subcutaneous B16-F0 mouse tumors were treated with anti-Ang2 injections and radiation. 5 days after radiation, tumors were collected and dissociated to obtain single cells and analyzed using the Chromium Single-cell 3'RNA-sequencing system
Project description:Most metastatic melanoma patients show variable responses to radiotherapy and do not benefit from immune checkpoint inhibitors (ICIs). Improved strategies for combination therapy that leverage potential benefits from radiotherapy and ICI are critical. Genes coding for subunits of GABAARs express functional GABAARs in melanoma cells. By enhancing GABAAR mediated anion transport, benzodiazepines depolarize melanoma cells and impair their viability. In vivo, benzodiazepine alone reduces tumor growth and potentiates radiotherapy and α-PD-L1 anti-tumor activity. Combination of benzodiazepine, radiotherapy, and α-PD-L1 results in near complete regression of treated tumors and a potent abscopal effect, mediated by increased infiltration of polyfunctional CD8+ T cells. Treated tumors show expression of cytokine:cytokine receptor interactions and overrepresentation of p53 signaling. This study identifies an anti-tumor strategy combining radiation and/or immune checkpoint inhibitor with modulation of GABAARs in melanoma using a benzodiazepine.
Project description:Radiotherapy is under investigation in the clinic for its ability to induce an in situ vaccine and enhance responses to immune checkpoint inhibitors and other immunotherapies. A variety of radiation doses and delivery schedules have been used to induce anti-tumor T cells in preclinical studies. However, the mechanisms bu which radiation induces anti-tumor T cells against poorly immunogenic tumors remain incompletely understood. In this study, we investigated changes in gene expression in mouse mammary carcinoma TSA tumors after a single dose (SD) of 20 Gy and a multi-fraction (MF) radiation regimen of 3x8Gy. To this end, TSA cells were injected into syngeneic BALB/c mice. When tumors became palpable, they were treated with local radiation therapy (RT) and harvested 4 or 24 hours later for gene expression analysis. The genome-wide microarray analysis showed key differences between SD and MF RT that may explain the differential ability of these two RT regimens to synergize with immune checkpoint inhibitors (Dewan et al., Clin Cancer Res 2009).
Project description:To investigate the diverse responses of the M4 mouse melanoma to immune checkpoint inhibitors, the tumors responding (R) and nonresponding (NR) to anti-CTLA-4 from a preclinical study of M4 melanoma were subjected to mRNA sequencing. The differentially expressed genes were analyzed to identify the signaling pathways that asscoiated with the therapeutic responses of the tumors.
Project description:B cells potentially play a role in the immune response to melanoma, including during treatment with immune modulators. We profiled (transcriptome analysis) effects of anti-PD-L1 antibody therapy on gene expression in B16 melanoma tumors of B cells depleted and WT syngeneic mice. After 7 days of B16 tumors implantation, mice were treated or untreated with anti-PD-L1 antibody (every three days).
Project description:Intracranial B16 melanoma tumors isolated from C57Bl6 mice were analyzed by mRNAseq. Four experimental groups were analyzed: (1) Mice with intracranial tumors receiving IgG; (2) Mice with intracranial tumors receiving anti-PD-1 plus anti-CTLA-4 therapy; (3) Mice with intracranial plus extracranial tumors receiving IgG; (4) Mice with intracranial plus extracranial tumors receiving anti-PD-1 plus anti-CTLA-4 therapy. Taggart et al., PNAS 2018;
Project description:Radiation enhances melanoma response to immunotherapeutic and synergizes with benzodiazepines to promote improved anti-tumor activity