Virtual Library

Start Your Search

M. Toki



Author of

  • +

    P2.01 - Poster Session with Presenters Present (ID 461)

    • Event: WCLC 2016
    • Type: Poster Presenters Present
    • Track: Biology/Pathology
    • Presentations: 1
    • +

      P2.01-046 - Quantitative Measurement of B7-H3 Protein Expression and Its Association with B7-H4, PD-L1 and TILs in NSCLC (ID 4288)

      14:30 - 14:30  |  Author(s): M. Toki

      • Abstract
      • Slides

      Background:
      B7-H3 (CD276) is a type I transmembrane protein that belongs to the B7 immunoregulatory family including PD-L1 (B7-H1) and is upregulated in multiple malignancies including Non-Small Cell Lung Cancer (NSCLC). Clinical activity of monoclonal B7-H3 blocking antibodies such as Enoblituzumab are under investigation. In this study we measured the levels of B7-H3 protein in NSCLC and studied its association with major tumor infiltrating lymphocyte (TIL) subsets, levels of PD-L1, B7-H4 and clinico-pathological characteristics in three independent NSCLC cohorts.

      Methods:
      We used automated quantitative immunofluorescence (QIF) to assess the levels of B7-H3 (clone D9M2L, CST), PD-L1 (clone SP142, Spring), B7-H4 (Clone D1M8I, CST) CD3, CD8 and CD20 in 634 NSCLC cases from 3 retrospective cohorts represented in tissue microarray format. The targets were selectively measured in the tumor and stromal compartments using co-localization with cytokeratin. Associations between the marker levels, major clinic-pathological variables and survival were analyzed.

      Results:
      Expression of B7-H3 protein was found in 80.4% (510/634) of the cases and the levels were higher in the tumor than in the stromal compartment. High B7-H3 protein expression level (top 10 percentile) was associated with poor survival in two out of three of the cohorts (p <0.05). Elevated B7-H3 was consistently associated with smoking history across the 3 cohorts, but not with sex, age, clinical stage and histology. Co-expression of B7-H3 and PD-L1 was found in 17.6% of the cases (112/634) and with B7-H4 in 10% (63/634). B7-H4 and PD-L1 were simultaneously detected only in 1.8% of NSCLCs (12/634). The expression of B7-H3 was not associated with the levels of CD3, CD8 and CD20 positive TILs.

      Conclusion:
      B7-H3 protein is expressed in the majority of NSCLCs and is associated with smoking history. High B7-H3 protein levels may have a prognostic effect in lung carcinomas. Elevated levels of B7-H3 are not associated with lymphocyte infiltration. Co-expression of B7-H3 with PD-L1 and B7-H4 is relatively low, suggesting a non-redundant biological role of these targets and possibilities for combination therapies using monoclonal antibodies.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.