The prognostic role of M2 tumor-associated macrophages in non-small-cell lung cancer

Tumor growth inhibition and immune system activation following treatment with thorium-227 conjugates and PD-1 check-point inhibition in the MC-38 murine model

Targeted thorium-227 conjugates comprise the combination of a monoclonal antibody with specificity for a tumor cell antigen and a 3,2-HOPO chelator enabling complexation of thorium-227 (Th-227). The radiolabeled conjugate functions as an effective delivery system of alpha-particle radiation to the surface of the tumor cell inducing difficult to repair complex DNA damage and cell death. In addition, the mechanism of action of targeted alpha therapy (TAT) appears to involve a significant component linked to stimulation of the immune system. We report herein evidence of immune activation and long-lasting immune protection of a TAT in a syngeneic model using the MC-38 murine cell line. Firstly, MC-38 cells were irradiated ex vivo with the thorium labeled antibody before subcutaneous implantation into mice. These mice were then rechallenged with MC-38 cells contra-laterally. In the group receiving irradiated cells, 9 out of 10 animals had no measurable tumor growth compared to aggressive tumor growth in the control group. Secondly, in an efficacy study, 500 kBq/kg of thorium labeled antibody alone or in combination with PD-1 checkpoint inhibitor gave statistically significant tumor growth inhibition compared to vehicle control. Animals with no measurable tumors were once again rechallenged contra-laterally with MC-38 cells. The re-growth of tumors was significantly delayed (approx. 60 days) in the treatment group compared to age-matched controls (approx. 30 days) in the monotherapy group. Interestingly, in the TAT/ PD-1 combination group no re-growth was observed demonstrating the potential of combining a TAT with checkpoint inhibition therapy. Finally, tumors were excised from treated mice and analyzed by flow cytometry and immunohistochemistry (IHC). Analysis revealed significant infiltration of CD8+ T-cells and mature dendritic cells compared to vehicle controls. Together these results indicated that an ongoing immune response from treatment with alpha radiation could be enhanced by check-point inhibition.

Prognostic implications of preoperative systemic inflammatory markers in oral squamous cell carcinoma, and correlations with the local immune tumor microenvironment

Purpose

The aim of this study was to investigate the prognostic significance of preoperative inflammatory markers in peripheral blood of patients with oral squamous cell carcinoma (OSCC), and to establish correlations with the infiltrate of macrophages and lymphocytes in the local immune tumor microenvironment (TME).

Materials and Methods

Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), lymphocyte-monocyte ratio (LMR), and systemic immune-inflammation index (SII) were retrospectively evaluated in a cohort of 348 OSCC patients, and correlated with overall (OS) and disease-specific survival (DSS). Immunohistochemical analysis of tumoral and stromal infiltration of CD8+, CD4+, FOXP3+ and CD20+ lymphocytes and CD68+ and CD163+ macrophages was performed in a subset of 119 OSCC patient samples, and correlations further assessed.

Results

NLR, SII, and LMR were significantly associated with a poorer OS in univariate analysis; however, only NLR remained a significant independent predictor in the multivariate analysis (HR = 1.626, p = 0.04). NLR and SII were inversely and significantly correlated with stromal infiltration of CD8+, CD4+, and CD20+ lymphocytes. Moreover, a significant correlation between LMR was also found to significantly associate with stromal infiltration of CD8+, CD4+, and CD20+ lymphocytes, stromal CD68+ and CD163+ macrophages, and also tumoral infiltration of CD4+ and CD20+ lymphocytes.

Conclusions

Preoperative NLR, SII, and LMR may serve as valuable systemic markers to predict OSCC patient survival, with NLR emerging as an independent predictor of poor OS. Moreover, strong significant correlations were exclusively observed between systemic inflammatory markers and the local stromal infiltration of lymphocytes in the TME.

Anaplastic lymphoma kinase-special immunity and immunotherapy

Alterations in the anaplastic lymphoma kinase (ALK) gene play a key role in the development of various human tumors, and targeted therapy has transformed the treatment paradigm for these oncogene-driven tumors. However, primary or acquired resistance remains a challenge. ALK gene variants (such as gene rearrangements and mutations) also play a key role in the tumor immune microenvironment. Immunotherapy targeting the ALK gene has potential clinical applications. Here, we review the results of recent studies on the immunological relevance of ALK-altered tumors, which provides important insights into the development of tumor immunotherapies targeting this large class of tumors.