Virtual Library
Start Your Search
T. Takahama
Author of
-
+
P2.07 - Immunology and Immunotherapy (ID 708)
- Event: WCLC 2017
- Type: Poster Session with Presenters Present
- Track: Immunology and Immunotherapy
- Presentations: 1
- Moderators:
- Coordinates: 10/17/2017, 09:30 - 16:00, Exhibit Hall (Hall B + C)
-
+
P2.07-021 - A Checkpoint Molecule B7-H3 as a Novel Immune Therapy Target for Non-Small Cell Lung Cancer (NSCLC) (ID 8598)
09:30 - 09:30 | Author(s): T. Takahama
- Abstract
Background:
Anti-PD-1 immune therapy improved survival in NSCLC, whereas some patients were not responding to this treatment, indicating the requirement of alternative strategies for these patients. B7-H3, an immune checkpoint molecule, has known to be expressed in some cancer cells including NSCLC. In this study, we examined the therapeutic potential of targeting B7-H3 using a mouse model, also elucidated the expression levels of B7-H3 on NSCLC tumor cells.
Method:
Pan02 murine cancer cells were inoculated in syngeneic mice, and anti-tumor efficacy of anti-B7-H3, anti-PD-L1 antibodies were evaluated. T-cell expression of IFN gamma was evaluated in the spleen and tumor infiltrating lymphocytes using flow-cytometer. B7-H3 expression on tumor cells in patients with NSCLC (n=69) was evaluated by immunohistochemistry.
Result:
In the mouse model study, the treatment with anti-B7-H3 antibody significantly prevented the tumor-growth as compared to isotype antibody. The numbers of CD4+ and CD8+ T-cells infiltrated in the tumor significantly increased following treatment with anti-B7-H3 antibody. Importantly, depletion of CD8+ T-cells cancelled the anti-tumor effect of anti-B7-H3 antibody treatment, indicating that the blockade of B7-H3 potentiates anti-tumor CD8+ T-cell responses. In fact, CD8+ T-cell expressions of IFN gamma in response to tumor cells were improved when mice were treated with anti-B7-H3 antibody. Furthermore, combination with anti-B7-H3 and anti-PD-L1 antibody treatment showed synergic effect in inhibiting tumor-growth. The expressions of B7-H3 were evident on NSCLC tumors, which consists 62% of NSCLC patients.
Conclusion:
Anti-B7-H3 antibody exhibited CD8+ T-cell-mediated anti-tumor effects in the mouse model study. B7-H3 was aberrantly expressed in NSCLC tumor cells. Anti-B7-H3 antibody or its combination with anti-PD-1 antibody is suggested to be effective for patients with NSCLC. Figure 1