ABSTRACT
Self-assembling carrier-free nanodrugs are attractive agents because they accumulate at tumor by an enhanced permeability and retention (EPR) effect without introduction of inactive substances, and some nanodrugs can alter the immune environment. We synthesized a peptidyl arginine deiminase 4 (PAD4) molecular inhibitor, ZD-E-1M. It could self-assembled into nanodrug ZD-E-1. Using confocal laser scanning microscopy, we observed its cellular colocalization, PAD4 activity and neutrophil extracellular traps (NETs) formation. The populations of immune cells and expression of immune-related proteins were determined by single-cell mass cytometry. ZD-E-1 formed nanoflowers in an acidic environment, whereas it formed nanospheres at pH 7.4. Accumulation of ZD-E-1 at tumor was pH-responsive because of its pH-dependent differences in the size and shape. It could enter the nucleus and bind to PAD4 to prolong the intracellular retention time. In mice, ZD-E-1 inhibited tumor growth and metastasis by inhibiting PAD4 activity and NETs formation. Besides, ZD-E-1 could regulate the ratio of immune cells in LLC tumor-bearing mice. Immunosuppressive proteins like LAG3 were suppressed, while IFN-γ and TNF-α as stimulators of tumor immune response were upregulated. Overall, ZD-E-1 is a self-assembling carrier-free nanodrug that responds to pH, inhibits PAD4 activity, blocks neutrophil extracellular traps formation, and improves the tumor immune microenvironment.
ABSTRACT
Lymphocyte activation gene-3 (LAG-3, CD223) is a class of immunosuppressive receptors, mainly expressed on the cell surface of activated T and natural killer (NK) cells. As with programmed death-1 (PD-1), T cell immunoglobulin domain and mucin domain-3 (TIM-3) and other immune check-points, the expression of LAG-3 in activated T cells is upregulated to prevent the occurrence of autoimmune diseases. In the tumor microenvironment, persistent antigenic stimulation can induce T cells to overexpress LAG-3 and other suppressor molecules, causing local immune suppression in the tumor microenvironment. However, the mechanism by which LAG-3 inhibits downstream signals of T-activation or interacts with other immunosuppressive molecules is still unknown. Preliminary clinical data has shown that anti-LAG-3 and anti-PD-1 antibodies possess synergistic effect on the treatment of tumors. Moreover, LAG-3 has different intracellular domains which are completely different from those of any other immunological negative regulatory molecules, suggesting that LAG-3 might have a unique molecular mechanism and prospect of application. Currently, there are at least 7 kinds of antibody drugs targeting LAG-3 and one kind of LAG-3-Fc fusion protein in clinical research, which indicates that anti-LAG-3 targeted drugs have a broad prospect of clinical application.
ABSTRACT
PURPOSE: In this study, we aimed to evaluate lymphocyte-activation gene-3 (LAG-3) expression and its prognostic value in neoadjuvant-treated triple-negative breast cancer (TNBC). METHODS: LAG-3, programmed death-1 (PD-1), programmed death ligand-1 (PD-L1), and CD8⁺ tumor-infiltrating lymphocyte (TILs) levels were examined using immunohistochemistry in 148 preand 114 post-neoadjuvant chemotherapy (NACT) specimens of human TNBC tissue. Correlations between expression levels and clinicopathological features were analyzed. Prognostic values for combined detection in TNBC following NACT were evaluated. RESULTS: In pre-NACT specimens, LAG-3 expression showed a significant association with pathological complete response (pCR, p=0.038) and was correlated with PD-1 (p<0.001) and PD-L1 (p=0.008). In post-NACT specimens, high expression of LAG-3 showed significant effects on nodal status (p=0.023) and PD-1 (p<0.001). The expression of immune markers on TILs significantly increased following NACT. Multivariate analysis indicated that only nodal status (odds ratio [OR], 0.226; 95% confidence interval [CI], 0.079–0.644; p=0.005) and high quantities of CD8⁺TILs (OR, 3.186; 95% CI, 1.314–7.721; p=0.010) are independent predictors of pCR. Nodal status (hazard ratio [HR], 2.666; 95% CI, 1.271–5.594; p=0.010), CD8⁺TILs (HR, 0.313; 95% CI, 0.139–0.705; p=0.005), and the LAG-3-high/PD-L1-high group (HR, 2.829; 95% CI, 1.050–7.623; p=0.040) provided prognostic values for patients with TNBC following NACT. CONCLUSION: CD8+TILs were sensitive predictive markers in response to NACT. High expression of LAG-3 in residual tissues, especially in combination with PD-L1, was associated with poor prognosis.
Subject(s)
Humans , Biomarkers , Drug Therapy , Immunohistochemistry , Lymphocytes, Tumor-Infiltrating , Multivariate Analysis , Neoadjuvant Therapy , Polymerase Chain Reaction , Prognosis , Triple Negative Breast NeoplasmsABSTRACT
Objective To investigate the effect of different stimulants on the LAG3 expression and function of spleen lymphocytes in mice. Methods The spleen lymphocytes from mice were isolated by density centrifugation.The LAG3 expressions in T cell subsets after exposure to conA, PMA, PHA or anti-CD3/28 antibodies for 24 h or 72 h were analyzed by Flow cytometry.The IFN-γsecretions of conditional medium were detected by ELISA kit.The proliferation of lymphocytes was examined by MTT analysis.Results Treatment with conA for 24 h or 72 h dose-dependently increased LAG3 +CD3 +and LAG3 +CD4 +CD3 +T cell percentages.Similarly, an exposure of anti-CD3/28 antibodies for 72 h significantly increased LAG3 +CD3 +and LAG3 +CD4 +CD3 + T cell percentages.Meanwhile, conA and anti-CD3/28 antibodies increased the IFN-γsecretion of lymphocytes in a time-dependent manner.Furthermore, Treatment with conA, PMA, PHA or anti-CD3/28 antibodies for 72 h could enhance the proliferation of lymphocyte. Conclusion conA and anti-CD3/28 antibodies are effective activators of T cells, and both of them could promote the expression of LAG3 and IFN-γsecretion of lymphocytes.