Prognostic Relevance of CD4+, CD8+ and FOXP3+ TILs in Oral Squamous Cell Carcinoma and Correlations with PD-L1 and Cancer Stem Cell Markers

Frequent PD-L1 expression in oral squamous cell carcinoma of non-smokers and non-drinkers, and association of tumor infiltrating lymphocytes with favorable prognosis

OBJECTIVES

To determine the presence and prognostic value of PD-L1 and PD-L2 expression, and tumor-infiltrating lymphocytes (TILs) in oral squamous cell carcinoma (OSCC) of non-smokers and non-drinkers (NSND).

MATERIALS AND METHODS

Clinical characteristics and tumor tissue of 86 NSND with OSCC were retrospectively collected and analyzed for protein expression on tissue microarrays. Immunohistochemistry was performed for expression of PD-L1 CPS, PD-L2 TPS, and PD-1, CD45, CD8, CD4, CD3, and FoxP3-positive TILs/mm2. Slides were digitally evaluated using QuPath. Differences in 5-year DFS and OS were determined by log rank analysis. Predictors for survival were determined by multivariable cox regression analysis.

RESULTS

Eighty-eight percent (76/86) of OSCC showed PD-L1 expression (CPS ≥1). Patients with high numbers of CD4-positive TILs showed a better DFS and OS than patients with low numbers of CD4-positive TILs. In the best multivariable model, CD4-positive TILs were an independent predictor for DFS (p = 0.010) and OS (p = 0.002) too. Additionally, patients with high numbers of CD45-positive TILs and a high CD8/FoxP3 ratio showed a better OS, of which the CD8/FoxP3 ratio was a near significant independent predictor (p = 0.050). Over 40 % of OSCC were PD-L1+/TIL+.

CONCLUSION

A large number of OSCC in NSND show PD-L1 expression (CPS ≥1). CD4 was a significant predictor for DFS and OS, in addition to the CD8/FoxP3 ratio being a near significant predictor for OS. The combination of frequent high CD8-positive TIL infiltrates in PD-L1-positive tumors makes NSND with OSCC in theory interesting candidates for treatment with immune checkpoint inhibitors.

Pathogenomic fingerprinting to identify associations between tumor morphology and epigenetic states

INTRODUCTION

Measuring the chromatin state of a tumor provides a powerful map of its epigenetic commitments; however, as these are generally bulk measurements, it has not yet been possible to connect changes in chromatin accessibility to the pathological signatures of complex tumors. In parallel, recent advances in computational pathology have enabled the identification of spatial features and immune cells within oral cavity tumors and their microenvironment.

METHODS

Here, we present pathogenomic fingerprinting (PaGeFin), a novel method that integrates morphological tumor features with chromatin states using ATAC-seq. This framework links spatial morphologic and epigenetic features, offering insights into tumor progression and immune evasion within and across tumors. Morphologic features describing spatial relationships between tumor and lymphocyte cells that are prognostic of oral cavity squamous cell carcinoma (OSCC) were identified through AI-driven pathology analysis. These pathomic features were spatially colocalized within the epigenome of 4 distinct sections of 4 OSCC tumors.

RESULTS

These key features pinpointed chromatin regions responsible for critical immune cell function through peak locations and enrichment analysis, highlighting loci of CD27+ memory B cells, helper CD4+ T cells, and cytotoxic CD8 naïve T cells that likely drive morphologic changes in the distribution of lymphocytes in the tumor microenvironment and promote aggressive tumor behavior. Gene Ontology analysis revealed that the CTLA4, CD79A, CD3D, and CCR7 genes were embedded in these regions.

CONCLUSION

This computational approach is the first to assess the correlation between pathomic and epigenetic features in the context of cancer.

New insights on anti-tumor immunity of CD8+ T cells: cancer stem cells, tumor immune microenvironment and immunotherapy

Recent breakthroughs in tumor immunotherapy have confirmed the capacity of the immune system to fight several cancers. The effective means of treating cancer involves accelerating the death of tumor cells and improving patient immunity. Dynamic changes in the tumor immune microenvironment alter the actual effects of anti-tumor drug production and may trigger favorable or unfavorable immune responses by modulating tumor-infiltrating lymphocytes. Notably, CD8+ T cells are one of the primary tumor-infiltrating immune cells that provide anti-tumor response. Tumor cells and tumor stem cells will resist or evade destruction through various mechanisms as CD8+ T cells exert their anti-tumor function. This paper reviews the research on the regulation of tumor development and prognosis by cancer stem cells that directly or indirectly alter the role of tumor-infiltrating CD8+ T cells. We also discuss related immunotherapy strategies.

Clinico-Pathological Significance of Tumor Infiltrating Immune Cells in Oral Squamous Cell Carcinoma-Hope or Hype?

BACKGROUND

To correlate between immunohistochemical expression of tumor-infiltrating lymphocytes (TILs), tumor-associated macrophages (TAMs), and natural killer (NK) cells with the AJCC 8th edition TNM staging system and other disease-modifying clinico-pathological variables.

METHODS

The representative histology sections of tumor invasive margin (IM) and tumor core (TC) were selected according to the International Immuno-Oncology Biomarker Working Group and were subjected to immunohistochemistry with antibodies for TILs (CD3, CD8, FOXP3), NK Cells (CD57), TAMs (CD68, CD163) and pan-leukocyte marker (CD45). Histo-immuno-density-intensity (HIDI) scoring was calculated as a product of the proportion and intensity of staining. Ordinal-ordinal and continuous-ordinal variables were correlated using Kendall's tau-b (τb), and binary-ordinal variables were correlated using Rank-Biserial (rrb) statistics.

RESULTS

A total of 111 patients were included in the study. None of the clinical and pathological parameters showed a strong correlation with any of the immune infiltrates including TNM staging.

CONCLUSION

We hypothesize an independent activity of tumor immunology in the disease prognosis.

TRIAL REGISTRATION

CTRI/2020/07/026335.

A Narrative Review of Prognostic Gene Signatures in Oral Squamous Cell Carcinoma Using LASSO Cox Regression

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies of the head and neck squamous cell carcinoma (HNSCC). HNSCC is recognized as the eighth most commonly occurring cancer globally in men. It is essential to distinguish between cancers arising in the head and neck regions due to significant differences in their etiologies, treatment approaches, and prognoses. As the Cancer Genome Atlas (TCGA) dataset is available in HNSCC, the survival analysis prognosis of OSCC patients based on the TCGA dataset for discovering gene expression-based prognostic biomarkers is limited. To address this paucity, we aimed to provide comprehensive evidence by recruiting studies that have reported new biomarkers/signatures to establish a prognostic model to predict the survival of OSCC patients. Using PubMed search, we have identified 34 studies that have been using the least absolute shrinkage and selection operator (LASSO)-based Cox regression analyses to establish signature prognosis that related to different pathways in OSCC from the past 4 years. Our review was focused on summarizing these signatures and implications for targeted therapy using FDA-approved drugs. Furthermore, we conducted an analysis of the LASSO Cox regression gene signatures. Our findings revealed 13 studies that correlated a greater number of regulatory T cells (Tregs) cells in protective gene signatures with increased recurrence-free and overall survival rates. Conversely, two studies displayed an opposing trend in cases of OSCC. We will also explore how the dysregulation of these signatures impacts immune status, promoting tumor immune evasion or, conversely, enhancing immune surveillance. Overall, this review will provide new insight for future anti-cancer therapies based on the potential gene that is associated with poor prognosis in OSCC.

Assessment of immune infiltrate in oral cancer: An immunohistochemical study

Background

The biomarkers of antitumour immune response provide valuable prognostic information and aid in the stratification and treatment of cancer. Tumour microenvironment (TME) defines the cancer biology, and assessment of tumour-infiltrating lymphocytes (TILs) in oral squamous cell carcinoma is an arena of vigorous research.

Aims and Objectives

The present study is designed to determine the association of CD8+ and CD3+ T lymphocytes with clinicopathological parameters and their role as prognostic biomarkers.

Materials and Methods

This is an observational and institution-based study. Tissue blocks of histologically proven oral squamous cell carcinoma patients were retrieved from archives, and all clinicopathological parameters were noted. The semiquantitative and quantitative methods of TILs assessment were meticulously applied both in the stromal and intratumoural regions using immunohistochemistry. The standard statistical methods were employed for data analysis.

Results

A significant association of CD8+ T lymphocytes with clinical tumour size (P = 0.012), clinical (P = 0.011), and pathological (P = 0.048) staging was observed. CD3+ T lymphocytes were significantly associated with clinical node involvement. However, no survival benefits were observed with both biomarkers.

Conclusion

CD8+ T lymphocytes showed a significant association with clinical tumour size, clinical, and pathological staging. However, the study did not provide evidence for the prognostic value of the presence of CD3+ and CD8+ T lymphocytes in the tumour epithelium and stroma of oral cancer patients.

Oral cancer immunology: state of the art and future perspectives

Oral cancer is a multifactorial disease involving genetic, epigenetic, and environmental factors. The literature indicates that inflammatory cells at the advancing front of the tumor induce a host immune response, preventing the spread of the tumor. However, cancer cells adopt various continued strategies to circumvent this immune surveillance. The complexity of immune mechanisms suggests that there must be virtually individual patterns of anti-tumor immune responses. Due to this important interaction of cancer with the immune system, the objective of the present study was to provide an up-to-date overview of immuno-oncology focused on oral cancer, summarizing the basic immunology, the classic risk factors, immunotherapy, and future treatment and prognostic perspectives.

Tumour-infiltrating lymphocyte subsets and their individual prognostic impact in oral squamous cell carcinoma

AIMS

Current understanding of oral squamous cell carcinoma (OSCC) is incomplete with regard to prognostic factors that lead to the considerable heterogeneity in treatment response and patient outcomes. We aimed to evaluate the impact of individual tumour-infiltrating lymphocyte (TIL) subsets on prognosis as a possible rationale for this, in a retrospective observational study.

METHODS

Immunohistochemistry was performed to quantitatively assess cell densities of CD3+, CD20+, CD4+, CD8+ and FOXP3+TIL subsets in 50 surgically treated OSCC cases. Results were correlated with disease-free survival (DFS) and overall survival (OS). Receiver operating characteristic curve analysis and Youden index were applied to determine prognostically significant cut-off values.

RESULTS

Mean counts for CD3+, CD4+, CD8+, CD20+ and FOXP3+TILs were 243, 52, 132, 53 and 116 cells per high power field, respectively. High CD8+ and low FOXP3+TIL counts, and high ratio of CD8:FOXP3 were significantly associated with longer DFS and OS, as well as with improved tumour-host interface parameters.

CONCLUSIONS

Host immune response and its interaction with cancer cells have a significant impact on OSCC outcomes, with some TIL subsets being more clinically relevant than others. High cytotoxic T-cell (CD8) and low Treg (FOXP3) counts, and high cytotoxic T-cell to Treg (CD8:FOXP3) ratio are significantly associated with favourable prognosis. These results may serve as a leading point in identifying novel therapeutic agents that can redesign the tumour immune microenvironment by reducing infiltrating FOXP3-lymphocytes, and modifying their signalling pathways.

The Expression of PDL-1 and PD1 in the Microenvironment of Oral Squamous Cell Carcinoma

OBJECTIVE

Immune checkpoint proteins, especially PD-1/PD-L1, play a vital role in controlling the intensity and duration of the immune response. However, cancer cells often over-expression PDL-1 on their surfaces, which leads to the permanent activation of the PD-1/PDL-1 pathway and exhaustion of T cells and creates a resistant tumor microenvironment. This study aimed to analyze PD-1, PD-L1 expression in tumor cells (PDL-1/TC) and in Tumor-Infiltrating Lymphocytes (PDL-1/TILS) of OSCC patients and associated with and to correlate it with histologic grade of malignancy and clinicopathologic parameters.

METHODS

The sample consisted of 43 archived specimens of 43 patients of OSCC with Clinical features (gender, age, smoking, clinical stage) collected from medical records between 2014-2021. The intensity of PD-1, PDL-1/TC, PDL-1/TILS, positive cells were assessed by immunohistochemistry.

RESULT

PDL-1/TILS and PDL-1/TC were observed in all specimens except two cases in well-differentiated were negative. PDL-1/TILS was significant between histological grades(P=0.004<0.05). There was no significant between PDL-1/TC and PDL-1/TILS and between poorly differentiated and moderately differentiated groups' ROC P values (P=0.133, 0.340>0.05) respectively. There is a difference between PDL-1/TC and PDL-1/TILS between poorly differentiated and well-differentiated groups ROC P value (0.005, 0.028), Sensitivity (0.857, 0.857), specificity (0.765, 0.824) respectively and there is a difference between and PDL-1/TILS moderate differentiated and well-differentiated groups ROC P value (0.133,) Sensitivity (0.737), specificity (0.765). No differences between PDL-1/TC and moderate and well-differentiated groups P value (0.173). There is a significant correlation between PDL-1/TC and PDL-1/TILS with an age P>65 value (0.032) in the well-differentiated group. PDL-1/TC and PDL-1/TILS with the depth of invasion (DOI) in the well-differentiated group. No significant correlation was obtained between PDL-1/TC and PDL-1/TILS and smoking, clinical stage, and gender. No significant correlation was obtained between PD1 and the histological grades or clinicopathologic characteristics.

CONCLUSION

PDL-1/TILS and PDL-1/TC are independent prognostic factors in OSCC and PDL1-/TILS has an important role.

Type I conventional dendritic cells and CD8+ T cells predict favorable clinical outcome of head and neck squamous cell carcinoma patients

Head and neck squamous cell carcinoma (HNSCC) is one of the most common tumor entities worldwide, with human papillomavirus (HPV) infection contributing to cancer development. Conventional therapies achieve only limited efficiency, especially in recurrent or metastatic HNSCC. As the immune landscape decisively impacts the survival of patients and treatment efficacy, this study comprehensively investigated the immunological tumor microenvironment (TME) and its association with patient outcome, with special focus on several dendritic cell (DC) and T lymphocyte subpopulations. Therefore, formalin-fixed paraffin-embedded tumor samples of 56 HNSCC patients, who have undergone resection and adjuvant radiotherapy, were analyzed by multiplex immunohistochemistry focusing on the detailed phenotypic characterization and spatial distribution of DCs, CD8+ T cells, and T-helper cell subsets in different tumor compartments. Immune cell densities and proportions were correlated with clinical characteristics of the whole HNSCC cohort and different HPV- or hypoxia-associated subcohorts. Tumor stroma was highly infiltrated by plasmacytoid DCs and T lymphocytes. Among the T-helper cells and CD8+ T cells, stromal regulatory T cells and intraepithelial exhausted CD8+ T cells expressing programmed cell death protein-1 (PD-1+) and/or lymphocyte-activation gene-3 (LAG-3+) were the predominant phenotypes, indicating an immunosuppressive TME. HPV-associated tumors showed significantly higher infiltration of type I and type II conventional DCs (cDC1, cDC2) as well as several CD8+ T cell phenotypes including exhausted, activated, and proliferating T cells. On the contrary, tumors with hypoxia-associated gene signatures exhibited reduced infiltration for these immune cells. By multivariate Cox regression, immune-related prognostic factors were identified. Patient clusters defined by high infiltration of DCs and T lymphocytes combined with HPV positivity or low hypoxia showed significantly prolonged survival. Thereby, cDC1 and CD8+ T cells emerged as independent prognostic factors for local and distant recurrence. These results might contribute to the implementation of an immune cell infiltration score predicting HNSCC patients' survival and such patient stratification might improve the design of future individualized radiochemo-(immuno)therapies.

Expression of CD4+ and CD8+ Tumor-Infiltrating Lymphocytes in Oral Squamous Cell Carcinoma and Their Relationship With Clinicopathological Parameters: A Cross-Sectional Study

Background Oral squamous cell carcinoma (OSCC) is the most common malignant neoplasm of the oral cavity. The tumor microenvironment (TME) is a dynamic ecosystem composed of components contributed by both the tumor and the host. The immune cells of TME, mainly CD4+ and CD8+ tumor-infiltrating lymphocytes (TILs), suppress the proliferation of cancer cells and play a crucial role in the progression of OSCC. The present study aims to analyze the immunohistochemical expression of CD4+ and CD8+ TILs in OSCC and to compare and correlate them with clinicopathological parameters. Methodology A total of 75 formalin-fixed paraffin-embedded samples of cases diagnosed with primary OSCC were immunostained with CD4+ and CD8+ antibodies and their expression was compared with the clinicopathological parameters. Results There was a significant positive correlation between CD4+ and CD8+ expression (r = 0.655, p = 0.001). Both CD4+ (r = -2.37, p = 0.041) and CD8+ (r = -0.348, p = 0.002) expressions negatively correlated with the TNM stage (r = -2.37, p = 0.041) of OSCC. CD8+ expression positively correlated with histopathological grade (r = 0.288, p = 0.012). Conclusions The study findings suggest that CD4+ cells are essential to maintain and sustain CD8+ TIL-mediated anti-tumor response. CD4+ and CD8+ TILs are key players in cell-mediated adaptive immunity and prevent tumor progression and metastasis. Strikingly, the higher grade of tumors despite heavy CD8+ infiltration may possibly be due to cancer immunoediting.

The Potential of FOXP3 in Predicting Survival and Treatment Response in Breast Cancer

Background

Breast cancer (BC) continues to pose a substantial challenge to global health, necessitating an enhanced understanding of its fundamental mechanisms. Among its various pathological classifications, breast invasive carcinoma (BRCA) is the most prevalent. The role of the transcription factor forkhead box P3 (FOXP3), associated with regulatory T cells, in BRCA's diagnosis and prognosis remains insufficiently explored, despite its recognized importance.

Methods

We examined the mRNA expression profile of FOXP3 in BRCA patients, assessing its correlation with disease detection, patient survival, immune checkpoint alterations, and response to anticancer drugs.

Results

Our analysis revealed significantly elevated FOXP3 mRNA levels in BRCA patients, with a 95.7% accuracy for BRCA detection based on the area under the curve. High FOXP3 mRNA levels were positively correlated with overall survival and showed significant associations with CTLA4, CD274, PDCD1, TMB, and immune cell infiltration status. Furthermore, FOXP3 mRNA expression was linked to the efficacy of anticancer drugs and the tumor inflammation signature.

Discussion

These findings suggest that FOXP3 serves as a promising biomarker for BRCA, offering valuable insights into its diagnosis and prognosis. The correlation between FOXP3 expression and immune checkpoint alterations, along with its predictive value for treatment response, underscores its potential in guiding therapeutic strategies.

Conclusion

FOXP3 stands out as an influential factor in BRCA, highlighting its diagnostic accuracy and prognostic value. Its association with immune responses and treatment efficacy opens new avenues for research and clinical applications, positioning FOXP3 as a vital target for further investigation in BRCA management.

Identification and Validation of a Prognostic Signature Derived from the Cancer Stem Cells for Oral Squamous Cell Carcinoma

The progression and metastasis of oral squamous cell carcinoma (OSCC) are highly influenced by cancer stem cells (CSCs) due to their unique self-renewal and plasticity. In this study, data were obtained from a single-cell RNA-sequencing dataset (GSE172577) in the GEO database, and LASSO-Cox regression analysis was performed on 1344 CSCs-related genes to establish a six-gene prognostic signature (6-GPS) consisting of ADM, POLR1D, PTGR1, RPL35A, PGK1, and P4HA1. High-risk scores were significantly associated with unfavorable survival outcomes, and these features were thoroughly validated in the ICGC. The results of nomograms, calibration plots, and ROC curves confirmed the good prognostic accuracy of 6-GPS for OSCC. Additionally, the knockdown of ADM or POLR1D genes may significantly inhibit the proliferation, migration, and invasion of OSCC cells through the JAK/HIF-1 pathway. Furthermore, cell-cycle arrest occurred in the G1 phase by suppressing Cyclin D1. In summary, 6-GPS may play a crucial role in the occurrence and development of OSCC and has the potential to be developed further as a diagnostic, therapeutic, and prognostic tool for OSCC.

Identification of SEC61G as a Diagnostic and Prognostic Biomarker in Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is a heterogeneous malignancy originating from the oral mucosal epithelium. Detecting novel biomarkers can offer crucial information on disease aggressiveness and expected clinical outcomes for individual patients. SEC61G, an aberrantly expressed gene in various cancers, has been associated with negative clinical outcomes. However, its expression and clinical significance in OSCC is still unclear. In the present study, we investigated the SEC61G expression level in OSCC using bioinformatic and immunohistochemical analyses. Additionally, our findings revealed a significant correlation between SEC61G expression and clinicopathological characteristics, as well as a worse prognosis in OSCC patients. Notably, flow cytometry analysis on patient samples revealed that SEC61G expression was also linked to decreased immune infiltration in OSCC patients. In conclusion, our study provides evidence supporting SEC61G's role as a potential diagnostic, prognostic, and therapeutic marker in OSCC.

Prognostic Significance of β-Catenin in Relation to the Tumor Immune Microenvironment in Oral Cancer

The aim of this study was to investigate the prognostic relevance of β-catenin expression in oral squamous cell carcinoma (OSCC) and to explore relationships with the tumor immune microenvironment. Expression of β-catenin and PD-L1, as well as lymphocyte and macrophage densities, were evaluated by immunohistochemistry in 125 OSCC patient specimens. Membranous β-catenin expression was detected in 102 (81.6%) and nuclear β-catenin in 2 (1.6%) tumors. There was an association between β-catenin expression, tumoral, and stromal CD8+ T-cell infiltration (TIL) and also the type of tumor immune microenvironment (TIME). Tumors harboring nuclear β-catenin were associated with a type II TIME (i.e., immune ignorance defined by a negative PD-L1 expression and low CD8+ TIL density), whereas tumors with membranous β-catenin expression were predominantly type IV (i.e., immune tolerance defined by negative PD-L1 and high CD8+ TIL density). Combined, but not individual, high stromal CD8+ TILs and membranous β-catenin expression was independently associated with better disease-specific survival (HR = 0.48, p = 0.019). Taken together, a combination of high stromal CD8+ T-cell infiltration and membranous β-catenin in the tumor emerges as an independent predictor of better survival in OSCC patients.

Patterns of Tumor-Infiltrating Lymphocytes Used to Distinguish Primary Cutaneous Squamous Cell Carcinomas That Metastasize

This case-control study examines the type, location, and density of tumor-infiltrating lymphocytes in adult patients with vs without metastatic cutaneous squamous cell carcinoma.

Prognostic impact of intra- and peritumoral immune cell subpopulations in head and neck squamous cell carcinomas - comprehensive analysis of the TCGA-HNSC cohort and immunohistochemical validation on 101 patients

Background

Due to the expanding role of immune checkpoint inhibition in the treatment of head and neck squamous cell carcinoma, understanding immunological processes in the tumor microevironment (TME) has strong translational importance. Though analytical methods for a comprehensive analysis of the immunological TME have constantly improved and expanded over the past years the prognostic relevance of immune cell composition in head and neck cancer TME largely remains ambiguous with most studies focusing on one or a small subset of immune cells.

Methods

The overall survival (OS) of the TCGA-HNSC patient cohort comprising 513 head and neck cancer patients was correlated with a total of 29 different immune metrics including a wide spectrum of immune cell subpopulations as well as immune checkpoint receptors and cytokines using RNAseq based immune deconvolution analyses. The most significant predictors of survival among these 29 immune metrics were validated on a separate HNSCC patient cohort (n=101) using immunohistochemistry: CD3, CD20+CXCR5, CD4+CXCR5, Foxp3 and CD68.

Results

Overall immune infiltration irrespective of immune cell composition showed no significant correlation with the patients' overall survival in the TCGA-HNSC cohort. However, when focusing on different immune cell subpopulations, naïve B cells (p=0.0006), follicular T-helper cells (p<0.0001), macrophages (p=0.0042), regulatory T cells (p=0.0306), lymphocytes (p=0.0001), and cytotoxic T cells (p=0.0242) were identified as highly significant predictors of improved patient survival. Using immunohistochemical detection of these immune cells in a second independent validation cohort of 101 HNSCC patients, we confirmed the prognostic relevance of follicular T helper cells, cytotoxic T cells and lymphocytes. In multivariable analysis, HPV negativity and advanced UICC stages were identified as additional prognostic biomarkers associated with poor outcome.

Conclusion

Our study highlights the prognostic relevance of the immunological tumor environment in head and neck cancer and demonstrates that a more detailed analysis of immune cell composition and immune cell subtypes is necessary to accurately prognosticate. We observed the highest prognostic relevance for lymphocytes, cytotoxic T cells, and follicular T helper cells, suggesting further investigations focusing on these specific immune cell subpopulations not only as predictors of patient prognosis but also as promising targets of new immunotherapeutic strategies.

Tumor Microenvironment and Immune Response in Lip Cancer

Tumor-infiltrating lymphocytes (TILs) play a significant role in cancer progression and prognosis of patients. The tumor microenvironment (TME) may affect the anti-tumor immune response. We examined the TIL and tertiary lymphoid structure (TLS) density in the invading front and inner tumor stroma, and the lymphocyte subpopulation (CD8, CD4, FOXP3) density in 60 squamous cell carcinomas of the lip. Analysis was performed in parallel with markers of hypoxia (hypoxia-inducible factor (HIF1α), lactate dehydrogenase (LDHA)) and angiogenesis. Low TIL density in the invading tumor front was related with larger tumor size (p = 0.05), deep invasion (p = 0.01), high smooth-muscle actin (SMA) expression (p = 0.01), and high HIF1α and LDH5 expression (p = 0.04). FOXP3⁺ TILs infiltration and FOXP3⁺/CD8⁺ ratios were higher in inner tumor areas, linked with LDH5 expression, and higher MIB1 proliferation index (p = 0.03) and SMA expression (p = 0.001). Dense CD4⁺ lymphocytic infiltration in the invading front is related to high tumor-budding (TB) (p = 0.04) and angiogenesis (p = 0.04 and p = 0.006, respectively). Low CD8⁺ TIL density, high CD20⁺ B-cell density, high FOXP3⁺/CD8⁺ ratio and high CD68⁺ macrophage presence characterized tumors with local invasion (p = 0.02, 0.01, 0.02 and 0.006, respectively). High angiogenic activity was linked with high CD4⁺, FOXP3⁺, and low CD8⁺ TIL density (p = 0.05, 0.01 and 0.01, respectively), as well as high CD68⁺ macrophage presence (p = 0.003). LDH5 expression was linked with high CD4⁺ and FOXP3⁺ TIL density (p = 0.05 and 0.01, respectively). Further research is needed to explore the prognostic and therapeutic value of TME/TIL interactions.

Immunoexpression of Tumor Infiltrating Lymphocytes(TILS) CD4 + and CD8 + in Oral Squamous Cell Carcinoma (OSCC) in Correlations with Clinicopathological Characteristics and Prognosis

OBJECTIVE

This study aimed to analyze CD4 +and CD8 + TILs in oral squamous cell carcinoma (OSCC) and to correlate it with histologic grade of malignancy and clinicopathologic data.

METHODS

The sample was composed of 43 archived specimens. Clinical features and histological grade of malignancy were obtained. The infiltrating intensity of CD4 +, CD8 positive cells were assessed by immunohistochemistry. One-way ANOVA was used to study the association between CD4 +, CD8 + and the grade of OSCC. The cut-off values of the proposed diagnostic indices were received from calculating the coordinates of the receiver operating characteristic (ROC) curve. For clinicopathologic data Independent-Samples T test, Pearson Correlation Coefficient, Correlation Coefficient were used clinicopathologic characteristics.

RESULTS

CD4 +and CD8 + were observed in all specimens. CD4 + were more frequent in poorly differentiated specimens (74.14) (P= 0.021<0.05). CD8 + were more frequent in well- differentiated  specimens (51.18). None of these correlations were significant (P=0.454>0.05). CD4 +/ CD8 ratio was higher in low-grade specimens (180.28) (P=0.017<0.05). No differences between CD4 +, CD8 +and CD4 +/ CD8 ratio between poorly- differentiated   and moderately- differentiated   groups ROC P value (0.370, 0.248, 0.126) respectively. there is a difference between CD4 +, CD4 +/ CD8ratio between poorly- differentiated   and well- differentiated   groups ROC P value (0.022, 0.341, 0.012) Sensitivity (0.857, 0.882), specificity (0.706, 0.857) respectively. and no differences between CD8 + poorly- differentiated and well- differentiated groups ROC P value (0.341). there is a difference between CD4 + between moderately - differentiated   and well- differentiated groups ROC P value (0.038) Sensitivity (0.368), specificity (0,765). No significant correlation was obtained with clinicopathologic findings of OSCC.

CONCLUSION

CD4 + and CD4 +/ CD8 + ratio are independent prognostic factor in OSCC.

Evaluation of CD4+ tumor-infiltrating lymphocyte association with some clinicopathological indices of oral squamous cell carcinoma

BACKGROUND

The delayed diagnosis of oral squamous cell carcinoma (OSCC) affects therapeutic and prognostic strategies, and provides regional recurrence or distant metastasis. The tumor-infiltrating lymphocytes (TILs) are known as a critical diagnostic biomarker in antitumor immune response. We evaluated the association between CD4⁺ T-lymphocyte marker, some clinicopathological indices, and the impact of TILs on the stage and grade of OSCC.

MATERIALS AND METHODS

In this cross-sectional study, 37 OSCC specimens including 16 early and 21 advanced stages (categorized base-on recent clinical oncology references) and their related healthy surgical margin (as internal control group) were collected. Obtained histochemical data were analyzed by SPSS V.23 software. The expression of CD4⁺ marker in tumor microenvironment (TME) was compared by nonparametric Mann-Whitney and Kruskal-Wallis as well as Fisher's exact tests. P < 0.05 was remarked statistically significant.

RESULTS

The low-grade patients represented more CD4⁺ TIL that was statistically significant (P = 0.011). However, there was no statistically significant difference in CD4⁺ TIL between various stages (P = 0.404), tumor size, and lymph node involvement (P > 0.05). Moreover, there was no significant relation between TIL infiltration, age, and tumor localization (P > 0.05), however CD4⁺ expression in women was more than men (P = 0.008). The CD4⁺ T-lymphocyte infiltration in TME was more significant than healthy surgical margin (P < 0.001). There was a statistically significant difference between healthy surgical margin and different grades and stages of OSCCs that lower grades demonstrated more CD4⁺ TIL infiltration (P < 0.001).

CONCLUSION

The CD4⁺ T-lymphocytes may play important role in differentiation and maturity of epithelial cell, tumorigenesis, and progression of OSCC.

T-Cell Infiltration and Immune Checkpoint Expression Increase in Oral Cavity Premalignant and Malignant Disorders

The immune cell niche associated with oral dysplastic lesion progression to carcinoma is poorly understood. We identified T regulatory cells (Treg), CD8+ effector T cells (Teff) and immune checkpoint molecules across oral dysplastic stages of oral potentially malignant disorders (OPMD). OPMD and oral squamous cell carcinoma (OSCC) tissue sections (N = 270) were analyzed by immunohistochemistry for Treg (CD4, CD25 and FoxP3), Teff (CD8) and immune checkpoint molecules (PD-1 and PD-L1). The Treg marker staining intensity correlated significantly (p < 0.01) with presence of higher dysplasia grade and invasive cancer. These data suggest that Treg infiltration is relatively early in dysplasia and may be associated with disease progression. The presence of CD8+ effector T cells and the immune checkpoint markers PD-1 and PD-L1 were also associated with oral cancer progression (p < 0.01). These observations indicate the induction of an adaptive immune response with similar Treg and Teff recruitment timing and, potentially, the early induction of exhaustion. FoxP3 and PD-L1 levels were closely correlated with CD8 levels (p < 0.01). These data indicate the presence of reinforcing mechanisms contributing to the immune suppressive niche in high-risk OPMD and in OSCC. The presence of an adaptive immune response and T-cell exhaustion suggest that an effective immune response may be reactivated with targeted interventions coupled with immune checkpoint inhibition.

Prognostic Role of Combined EGFR and Tumor-Infiltrating Lymphocytes in Oral Squamous Cell Carcinoma

Background

Epidermal growth factor receptor (EGFR) is well known as a general prognostic biomarker for head and neck tumors, however the specific prognostic value of EGFR in oral squamous cell carcinoma (OSCC) is controversial. Recently, the presence of tumor-infiltrating T cells has been associated with significant survival advantages in a variety of disease sites. The present study will determine if the inclusion of T cell specific markers (CD3, CD4 and CD8) would enhance the prognostic value of EGFR in OSCCs.

Methods

Tissue microarrays containing 146 OSCC cases were analyzed for EGFR, CD3, CD4 and CD8 expression using immunohistochemical staining. EGFR and T cell expression scores were correlated with clinicopathological parameters and survival outcomes.

Results

Results showed that EGFR expression had no impact on overall survival (OS), but EGFR-positive (EGFR+) OSCC patients demonstrated significantly worse progression free survival (PFS) compared to EGFR-negative (EGFR-) patients. Patients with CD3, CD4 and CD8-positive tumors had significantly better OS compared to CD3, CD4 and CD8-negative patients respectively, but no impact on PFS. Combined EGFR+/CD3+ expression was associated with cases with no nodal involvement and significantly more favorable OS compared to EGFR+/CD3- expression. CD3 expression had no impact on OS or PFS in EGFR- patients. Combinations of EGFR/CD8 and EGFR/CD4 expression showed no significant differences in OS or PFS among the expression groups.

Conclusion

Altogether these results suggest that the expression of CD3+ tumor-infiltrating T cells can enhance the prognostic value of EGFR expression and warrants further investigation as prognostic biomarkers for OSCC.

Beyond PD-L1—Identification of Further Potential Therapeutic Targets in Oral Cancer

Simple Summary

Tumor immunotherapy is rapidly evolving and approved for the treatment of advanced OSCC cases. In addition, the currently observed shift in the use of checkpoint inhibitors from palliative to neoadjuvant treatment may improve survival. However, not all patients respond to currently applied immune checkpoint inhibitors. Therefore, further immune targets for therapeutic approaches are urgently needed. However, there are limited data on immune checkpoint expression in OSCC. This study aimed to perform a comparative analysis of a large number of immune modulators in OSCC compared with healthy controls by NanoString mRNA analysis in order to identify possible targets for therapeutic applications. We were able to ascertain several cellular markers, checkpoints and their correlation, as well as their association with histomorphological parameters. Hence, the study contributes to the understanding of immune escape in OSCC and reveals potential targets for immunotherapy of oral cancer.

Abstract

Background: The involvement of immune cell infiltration and immune regulation in the progression of oral squamous cell carcinoma (OSCC) is shown. Anti-PD-1 therapy is approved for the treatment of advanced OSCC cases, but not all patients respond to immune checkpoint inhibitors. Hence, further targets for therapeutic approaches are needed. The number of identified cellular receptors with immune checkpoint function is constantly increasing. This study aimed to perform a comparative analysis of a large number of immune checkpoints in OSCC in order to identify possible targets for therapeutic application. Materials and Methods: A NanoString mRNA analysis was performed to assess the expression levels of 21 immune regulatory checkpoint molecules in OSCC tissue (n = 98) and healthy oral mucosa (NOM; n = 41). The expression rates were compared between the two groups, and their association with prognostic parameters was determined. Additionally, relevant correlations between the expression levels of different checkpoints were examined. Results: In OSCC tissue, significantly increased expression of CD115, CD163, CD68, CD86, CD96, GITRL, CD28 and PD-L1 was detected. Additionally, a marginally significant increase in CD8 expression was observed. BTLA and PD-1 levels were substantially increased, but the differential expression was not statistically significant. The expression of CD137L was significantly downregulated in OSCC compared to NOM. Correlations between immune checkpoint expression levels were demonstrated, and some occurred specifically in OSCC tissue. Conclusions: The upregulation of inhibitory receptors and ligands and the downregulation of activators could contribute to reduced effector T-cell function and could induce local immunosuppression in OSCC. Increased expression of activating actors of the immune system could be explained by the increased infiltration of myeloid cells and T-cells in OSCC tissue. The analysis contributes to the understanding of immune escape in OSCC and reveals potential targets for oral cancer immunotherapy.

PD-L1 expression and intra-tumoral CD8 + T lymphocytes in esophageal carcinosarcoma

We detected PD-L1 and intra-tumoral CD8⁺ T lymphocytes (CD8⁺ TIL) in 19 patients with esophageal carcinosarcoma (ECS). The median follow-up period of these patients was 43 months, and the three- and five-year survival rates were 78.9% and 63.2%, respectively. No statistically significant correlation was observed between PD-L1 and CD8⁺ TIL in sarcomatous components(SC) (r = -0.262, P = 0.279) and epithelial carcinomatous (EC) (r = 0.055, P = 0.824).This study examined the immunological markers in ECS for the first time. PD-L1 is highly expressed in the SC and is associated with a poorer prognosis.

High PD-L1 Expression on Tumor Cells Indicates Worse Overall Survival in Advanced Oral Squamous Cell Carcinomas of the Tongue and the Floor of the Mouth but Not in Other Oral Compartments

The markers of the tumor microenvironment (TME) are promising prognostic and predictive factors in oral squamous cell carcinoma (OSCC). The current study aims to analyze the immunohistochemical expression of programmed cell death-ligand 1 (PD-L1) and interleukin-33 (IL-33) in a cohort of 95 chemonaïve OSCCs. PD-L1 and IL-33 were assessed separately in tumor cells (TCs) and tumor-infiltrating lymphocytes (TILs). High PD-L1 expression in TILs was associated with better overall survival (OS) in univariate analysis. Tumors localized in the floor of the oral cavity and tongue tended to have a lower percentage of PD-L1-positive TCs when compared to other locations. PD-L1 expression on TCs had no prognostic significance when the whole cohort was analyzed. However, along with the T descriptor (TNM 8th), it was included in the multivariable model predicting death in carcinomas of the floor of the oral cavity and tongue (HR = 2.51, 95% CI = 1.97-5.28). In other locations, only nodal status was identified as an independent prognostic factor in multivariate analysis (HR = 0.24, 95% CI = 0.08-0.70). Expression of IL-33 had no impact on survival, but it was differently expressed in various locations. In conclusion, the prognostic significance of PD-L1 in oral cancer depends on the tumor site and type of cell expressing immune checkpoint receptor (TCs vs. TILs).

Novel Insights into the Immunotherapy of Soft Tissue Sarcomas: Do We Need a Change of Perspective?

Soft tissue sarcomas (STSs) are rare mesenchymal tumors. With more than 80 histological subtypes of STSs, data regarding novel biomarkers of strong prognostic and therapeutic value are very limited. To date, the most important prognostic factor is the tumor grade, and approximately 50% of patients that are diagnosed with high-grade STSs die of metastatic disease within five years. Systemic chemotherapy represents the mainstay of metastatic STSs treatment for decades but induces response in only 15–35% of the patients, irrespective of the histological subtype. In the era of immunotherapy, deciphering the immune cell signatures within the STSs tumors may discriminate immunotherapy responders from non-responders and different immunotherapeutic approaches could be combined based on the predominant cell subpopulations infiltrating the STS tumors. Furthermore, understanding the immune diversity of the STS tumor microenvironment (TME) in different histological subtypes may provide a rationale for stratifying patients according to the TME immune parameters. In this review, we introduce the most important immune cell types infiltrating the STSs tumors and discuss different immunotherapies, as well as promising clinical trials, that would target these immune cells to enhance the antitumor immune responses and improve the prognosis of metastatic STSs patients.