Abstract 2996
Background
Myeloid derived suppresor cells (MDSC) are a heterogeneous population of immature myeloid cells that inhibits antitumor responses by T lymphocytes. High levels of MDSC have been found in the tumor microenvironment, which is correlated with a poor prognosis of the disease. Our purposes are to evaluate the objective response rate (ORR) to test the treatment efficacy and to show the decrease of MDSC in clinical benefit (CB) patients, that includes complete response (CR), partial response (PR) and stabilization of disease (SD), when compared with progression of disease (PD).
Methods
58 patients diagnosed of R/R DLBCL who were not high dose chemotherapy and autologous bone narrow transplantation candidates were recruited from Spanish hospitals. The patients progressed to a prior R-CHOP therapy and had ECOG ≤ 1. They were treated with the R2-GDP chemotherapy schedule (rituximab, lenalidomide, gemcitabine, dexamethasone and cisplatin). Three peripheral blood analysis were carried out: basal, cycle 3 (C3) and end of induction (EI) by flow cytometry to determine the MDSC level.
Results
30 patients obtained CB response to treatment (PR 11 patients, CR 14 patients and SD 5 patients) and 28 patients obtained PD. A remarkable decrease of MDSC is shown in the Table, except in PD patients. On the other hand, ORR was 69% at C3 (PR 53%+ CR 16%) and 66% at EI (PR 40% + CR 26%).Table:
1267P MDSC levels (cells/uL) in CB (CR, PR, SD) and PD. Av: average; St: Standard Deviation; *: Statistically significant differences (P < 0.05) compared with basal
Response | Basal Av (St) | C3 Av (St) | EI Av (St) |
---|---|---|---|
CB | 19.9 (4.0) | 10.0 (3.1) | 4.8 (2.1)* |
CR | 18.6 (4.9) | 12.4 (3.7) | 2.7 (1.1)* |
PR | 13.0 (3.2) | 4.5 (0.8) | 1.4 (0.5)* |
SD | 35.3 (14.8) | 18.8 (11.6) | 18.5 (9.2) |
PD | 10.7 (4.0) | 8.6 (2.4) | 12.2 (2.9) |
Conclusions
The ORR obtained shown the treatment efficacy in R/R DLBCL to stimulate the immune system antitumor response, which explains the decrease of MDSC in all CB groups and a non-important increase in PD patients. Based on these results, MDSC seem to be an important therapeutic target against tumor progression, as well as being a potentially promising marker of response.
Clinical trial identification
EudraCT number: 2014-001620-29.
Editorial acknowledgement
Legal entity responsible for the study
Grupo Español para el Tratamiento y Estudio de los Linfomas (GOTEL).
Funding
Grupo Español para el Tratamiento y Estudio de los Linfomas (GOTEL).
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
2115 - Preclinical in vivo screening to predict responder patients depend on EGFR status
Presenter: Yejin Kim
Session: Poster Display session 3
Resources:
Abstract
3349 - Interplay between miR-17-5p and MALAT-1 Shapes The Cytokine Storm in Triple Negative Breast Cancer (TNBC) Tumor Microenvironment
Presenter: Raghda Soliman
Session: Poster Display session 3
Resources:
Abstract
4014 - Clinical verification on the relationship between lipid metabolism and the immune microenvironment of breast cancer
Presenter: Wataru Goto
Session: Poster Display session 3
Resources:
Abstract
4158 - The clinical and transcriptional signatures of human CD204 reveal an applicable marker for tumor associated macrophage in breast cancer
Presenter: Yunjie He
Session: Poster Display session 3
Resources:
Abstract
5392 - Activated effector T cells co-expressing multiple inhibitory receptors (IRs) are enriched in the tumor immune microenvironment in high grade serous ovarian cancer (HGSOC)
Presenter: Alice Bergamini
Session: Poster Display session 3
Resources:
Abstract
2617 - Oncolytic reovirus as a new anti-tumor strategy in castration resistant prostate cancer
Presenter: Yunlim Kim
Session: Poster Display session 3
Resources:
Abstract
2995 - Dysregulation of helper T lymphocytes in esophageal squamous cell carcinoma (ESCC) patients is highly associated with aberrant production of miR-21
Presenter: Ali Memarian
Session: Poster Display session 3
Resources:
Abstract
3597 - Myeloid derived suppressor cells but not regulatory T cells are associated with adaptive immunity and clinical outcomes in anal squamous cell carcinoma
Presenter: Christophe Borg
Session: Poster Display session 3
Resources:
Abstract
3430 - Evaluation of immune responses among responders (R) and non-responders (non-R) in a humanized mouse model with colorectal cancer (CRC) xenografts treated with combination immunotherapy
Presenter: Juan Marín Jiménez
Session: Poster Display session 3
Resources:
Abstract
1995 - ¬¬Advanced melanoma patients with high CD16+ macrophages have better response and survival to anti-PD-1 based immunotherapy
Presenter: Hansol Lee
Session: Poster Display session 3
Resources:
Abstract