The Oncolytic Adenovirus XVir-N-31 Joins Forces with CDK4/6 Inhibition Augmenting Innate and Adaptive Antitumor Immunity in Ewing Sarcoma.

PURPOSE: Ewing sarcoma (EwS) is a highly malignant pediatric tumor characterized by a non-T-cell-inflamed immune-evasive phenotype. When relapsed or metastasized, survival is poor, emphasizing the need for novel treatment strategies. Here, we analyze the novel combination approach using the YB-1-driven oncolytic adenovirus XVir-N-31 and CDK4/6 inhibition to augment EwS immunogenicity. EXPERIMENTAL DESIGN: In vitro, viral toxicity, replication, and immunogenicity were studied in several EwS cell lines. In vivo tumor xenograft models with transient humanization were applied to evaluate tumor control, viral replication, immunogenicity, and dynamics of innate as well as human T cells after treatment with XVir-N-31 combined with CDK4/6 inhibition. Furthermore, immunologic features of dendritic cell maturation and T-cell-stimulating capacities were assessed. RESULTS: The combination approach significantly increased viral replication and oncolysis in vitro, induced HLA-I upregulation, and IFNγ-induced protein 10 expression and enhanced maturation of monocytic dendritic cells with superior capacities to stimulate tumor antigen-specific T cells. These findings were confirmed in vivo showing tumor infiltration by (i) monocytes with antigen-presenting capacities and M1 macrophage marker genes, (ii) TReg suppression in spite of adenovirus infection, (iii) superior engraftment, and (iv) tumor infiltration by human T cells. Consequently, survival was improved over controls with signs of an abscopal effect after combination treatment. CONCLUSIONS: The joint forces of the YB-1-driven oncolytic adenovirus XVir-N-31 and CDK4/6 inhibition induce therapeutically relevant local and systemic antitumor effects. Innate as well as adaptive immunity against EwS is boosted in this preclinical setting, pointing toward high therapeutic potential in the clinic.

Serum protein S100ß is a diagnostic biomarker for distinguishing posterior circulation stroke from vertigo of nonvascular causes.

BACKGROUND: In patients presenting with acute vertigo or dizziness, identifying the posterior fossa stroke as the underlying cause can be a major challenge. We therefore evaluated the serum biomarkers for the differential diagnosis of nonvascular vertigo and posterior circulation stroke. METHODS: Of a total of 80 patients, 31 patients had an ischemic stroke in the posterior circulation and 12 infratentorial hemorrhage. Findings in these patients were compared with those in 22 patients with vertigo of nonvascular origin and 15 matched control patients without neurological symptoms. Blood samples drawn <24 h after symptom onset were analyzed for S100 calcium-binding protein B (S100ß), matrix metalloproteinase 9 (MMP-9), soluble vascular cellular adhesion molecule-1 (sVCAM-1), and glial fibrillary acidic protein (GFAP). RESULTS/CONCLUSION: Serum levels of S100ß were significantly higher in stroke patients than in nonvascular vertigo patients. Serum concentrations of MMP-9 tended to be higher in stroke patients, whereas no significant differences among groups were found for sVCAM-1 and GFAP. Receiver-operating characteristic analysis revealed a sensitivity of 94.4% and a specificity of 31.8% for detecting stroke in patients presenting with vertigo for S100ß. S100ß may serve as a biomarker for distinguishing between vertigo of vascular causes and nonvascular, acute vertigo.