Abstract P5-04-21: Analysis of serum immune biomarkers for response to therapeutic personalized peptide vaccination in patients with metastatic breast cancer

Abstract

Abstract Purpose: Our results from the previous clinical trials using personalized peptide vaccines (PPV) combined conventional chemo-hormonal therapies have confirmed the potential for clinical benefit in patients who had higher IgG antibody and/or CTL response to the immunized PPV (SABCS 2018 U Toh etc.). The aim of this study is to evaluate the association between the serum immunologic factors including cytokines, haptoglobin (HP), B-cell activating factor (BAFF) etc. and the clinical outcome of patients(pt) with metastatic breast cancer (mBC) who treated by personalized peptide vaccines (PPV). Methods: Peripheral blood samples from 57 pts and 52 pts obtained before and after the vaccination of PPV, respectively. Serum HP and IL-6 were analyzed by ELISA(R&D Systems, Life Technologies)and bead-based multiplex assays(Luminex 200 system)were performed for GM-CSF,IFN-γ,TNF-α, BAFF, TGF-β, IFNγ-induced protein 10(IP-10), IL-1β, IL-2,-4,-5,-8, -10. The association between each factor and clinical outcome was statistically evaluated. Results: Pt’s group (n=28) with low BAFF and high HP level (>544 pg/ml), high IFN-γ and high HP level or low IL-8 and high HP level before PPV treatment showed a significantly shorter median survival time (MST; p=0.015;0.068;0.002, respectively). There was no difference in high BAFF, low IFN-γ or high IL-8 level group(n=29). In contrast, pt’s group with low serum level of IL-10, GM-CSF, IL-5, IL-4 and low HP level (<544 pg/ml MV) after PPV treatment associated with significantly shorter MST (p=0.002; 0.001; 0.001; <0.001, respectively). Conclusions: The combination of serum levels of HP and BAFF, IFN-γ or cytokines of IL-8, -10, - 5, -4 might be useful prognostic biomarkers for mBC pts receiving PPV therapy. Citation Format: Uhi Toh, Shuko Saku, Yuko Takao, Sayaka Sakurai, Miki Takenaka, Shigeki Shichijo, Kyogo Itoh, Yoshito Akagi. Analysis of serum immune biomarkers for response to therapeutic personalized peptide vaccination in patients with metastatic breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-04-21.