Early changes in the immune microenvironment of oral potentially malignant disorders reveal an unexpected association of M2 macrophages with oral cancer free survival

Abstract

Understanding the dynamics of the immune microenvironment is critical to the development of immuno-based strategies for the prevention of oral potentially malignant disorders transformation to oral squamous cell carcinoma (OSCC). We used laser capture microdissection and RNA-sequencing to profile the expression of 13 matched pairs of epithelial versus stromal compartments from normal mucosa, hyperplasia, dysplasia, and invasive tumors in the 4-nitroquinolein (4-NQO) murine model of oral carcinogenesis. Genes differentially expressed at each step of transformation were defined. Immune cell deconvolution and enrichment scores of various biological processes including immune-related ones were computed. Immunohistochemistry was also performed to characterize the immune infiltrates by T-cells (T-cells CD3+, helper CD4+, cytotoxic CD8+, regulatory FoxP3+), B-cells (B220+), and macrophages (M1 iNOS+, M2 CD163+) at each histological step. Enrichment of three independent M2 macrophages signatures were computed in 86 oral leukoplakia with available clinical outcome. Most gene expression changes were observed in the stromal compartment and related to immune biological processes. Immune cell deconvolution identified infiltration by the macrophage population as the most important quantitatively especially at the stage of dysplasia. In 86 patients with oral leukoplakia, three M2 macrophages signatures were independently associated with improved oral cancer-free survival. This study provides a better understanding of the dynamics of the immune microenvironment during oral carcinogenesis and highlights an unexpected association of M2 macrophages gene expression signatures with oral cancer free survival in patients with oral leukoplakia.

Genetic Changes Driving Immunosuppressive Microenvironments in Oral Premalignancy

“…Bouaoud et al. used immune cell deconvolution and enrichment algorithms for RNAseq as well as immunohistochemistry on OPL to observe that M2 macrophages were associated with dysplasia and OSCC even though 3 M2 TAM signatures were associated with better oral cancer-free survival ( 34 ). By contrast, Mori et al.…”

“…However, some groups indicate that TAMs may inhibit OPL regardless of M1 or M2 phenotype. Bouaoud et al used immune cell deconvolution and e n r i c h m e n t a l g o r i t h m s f o r R N A s e q a s w e l l a s immunohistochemistry on OPL to observe that M2 macrophages were associated with dysplasia and OSCC even though 3 M2 TAM signatures were associated with better oral cancer-free survival (34). By contrast, Mori et al demonstrated that the M2 canonical marker CD163 may identify TAMs with an inflammatory rather than immunosuppressive phenotype.…”

The Overexpression of Fibronectin 1 Promotes Cancer Progression and Associated with M2 Macrophages Polarization in Head and Neck Squamous Cell Carcinoma Patients

“… 46–50 Moreover, recent studies have presented convincing evidence that copious M2 macrophages in TME are significantly associated with deteriorated OS in HNSCC patients. 51–55 Through establishing a co-culture system using CM of FN1-deficient HNSCC cells, we observed an obvious decrease in the expression of M2 macrophage markers. These results suggest that FN1 may induce macrophage M2 polarization in HNSCC.…”

Lactobacillus Suppresses Tumorigenesis of Oropharyngeal Cancer via Enhancing Anti-Tumor Immune Response

“…Mice were randomly assigned into two cages in each group for collecting feces and recording survival. We randomly divided BABL/c male mice into an experimental group ( n = 20) provided with drinking water containing 100 mg/L 4NQO (sigma, United States) and into a control group ( n = 20) provided with drinking water without 4NQO ( Bouaoud et al, 2021 ). Five mice were randomly sacrificed every 4 weeks, continuously for 16 weeks.…”