Identification of novel subtypes based on ssGSEA in immune-related prognostic signature for tongue squamous cell carcinoma.

BACKGROUND: Tongue squamous cell carcinoma (TSCC) is characterized by aggressive invasion and poor prognosis. Currently, immune checkpoint inhibitors may prolong overall survival compared with conventional treatments. However, PD1/PDL1 remain inapplicable in predicting the prognosis of TSCC; thus, it is urgent to explore the genetic characteristics of TSCC. MATERIALS AND METHODS: We utilized single-sample gene set enrichment analysis (ssGSEA) to classify TSCC patients from the TCGA database into clusters with different immune cell infiltrations. ESTIMATE (immune-related scores) and CIBERSORT (immune cell distribution) analyses were used to evaluate the immune landscape among clusters. GO, KEGG, and GSEA analyses were performed to analyze the different underlying molecular mechanisms in the clusters. Based on the immune characteristics, we applied the LASSO Cox regression to select hub genes and construct a prognostic risk model. Finally, we established an interactive network among these hub genes by using Cytoscape, and a pan-cancer analysis to further verify and decipher the innate function of these genes. RESULTS: Using ssGSEA, we constructed three functional clusters with different overall survival and immune-cell infiltration. ESTIMATE and CIBERSORT analyses revealed the different distributions of immune cells (T cells, B cells, and macrophages) with diverse immune-related scores (ESTIMATE, immune, stromal, and tumor purity scores). Moreover, pathways including those of the interferon-gamma response, hypoxia, and glycolysis of the different subtypes were investigated to elucidate their involvement in mediating the heterogeneous immune characteristics. Subsequently, after LASSO Cox regression, a signature of 15 immune-related genes was established that is more prognostically effective than the TNM stage. Furthermore, three hub genes-PGK1, GPI, and RPE-were selected using Cytoscape evaluation and verified by immunohistochemistry. PGK1, the foremost regulator, was a comprehensively profiled pan-cancer, and a PGK1-based interactive network was established. CONCLUSION: Our results suggest that immune-related genes and clusters in TSCC have the potential to guide individualized treatments.

A new PD-1-specific nanobody enhances the antitumor activity of T-cells in synergy with dendritic cell vaccine.

Despite the many successes and opportunities presented by PD-1 blockade in cancer therapies, anti-PD-1 monoclonal antibodies still face multiple challenges. Herein we report a strategy based on a nanobody (Nb) to circumvent these obstacles. A new PD-1-blocking Nb (PD-1 Nb20) in combination with tumor-specific dendritic cell (DC)/tumor-fusion cell (FC) vaccine that aims to improve the activation, proliferation, cytokine secretion, and tumor cell cytotoxicity of CD8+ T-cells. This combination was found to effectively enhance the in vitro cytotoxicity of CD8+ T-cells to kill human non-small cell lung cancer (NSCLC) HCC827 cells, hepatocellular carcinoma (HCC) HepG2 cells, and tongue squamous cell carcinoma (TSCC) Tca8113 cells. Moreover, CD8+ T-cells pre-treated with PD-1 Nb20 and tumor-specific DC/tumor-FCs significantly suppressed the growth of NSCLC-, HCC- and TSCC-derived xenograft tumors and prolonged the survival of tumor-bearing mice, through promoting T-cell infiltration to kill tumor cells and inhibiting tumor angiogenesis. These data demonstrate that PD-1 Nb20 in synergy with DC/tumor-FC vaccine augment the broad spectrum of antitumor activity of CD8+ T-cells, providing an alternative and promising immunotherapeutic strategy for tumor patients who are T-cell-dysfunctional or not sensitive to anti-PD-1 therapy.

Assessment of the presence of interleukin 17+ macrophages and Th17 cells in situ in lip and oral tongue cancer.

Increasing clinical evidence indicates that Th17 cells may promote or inhibit tumor progression, however the exact role of these cells in Oral Squamous Cell Carcinoma (OSCCs) pathogenesis and progression remains unclear. Tumor associated macrophages are highly plastic phenotype cells which can differentiate as M1 or M2. The mechanism and cellular phenotype of IL-17 expressing macrophages are unknown. 40 cases of lip and 28 of tongue SCCs were submitted to immunohistochemical analysis, and histologically graded. In tongue cases TNM was analyzed. The number of IL-17+ T cells was higher in lip SCC (p = 0.028). IL-17+ macrophages was greater in tongue SCC (p = 0.014). There were more IL-17+ macrophages in the high-grade malignancy oral tongue SCCs (p = 0.016), yet there was no significant difference in the numbers of RORγt+ lymphocytes by histopathological or TNM analysis. This study provides evidence concerning IL-17's pleiotropic roles, being possibly dependent on its cellular sources in the tumor microenvironment.

Histologic evaluation of host immune microenvironment and its prognostic significance in oral tongue squamous cell carcinoma: a comparative study on lymphocytic host response (LHR) and tumor infiltrating lymphocytes (TILs).

BACKGROUND: Host immune microenvironment is a key component of anti-tumoral immune response, influencing tumor progression, regression, and treatment responses. There is a need for simple and reliable histologic measurements of host immune response in routine histopathologic diagnosis. METHODS: The prognostic value of lymphocytic host response (LHR), a qualitative histologic grading scheme, was compared to stromal/intratumoral TIL (sTIL/iTIL) percentage, a quantitative measurement in a retrospective study of 329 patients with oral tongue squamous cell carcinoma (OTSCC) of 4 cm or less in size. RESULTS: High sTIL predicted improved distant recurrence free survival on univariate survival analysis and was an independent prognostic factor for better overall survival on multivariate analysis. LHR and iTIL were not associated with the risk of nodal metastasis or outcome. CONCLUSIONS: sTIL appears to be a superior quantitative histologic measurement for the host immune microenvironment compared with the qualitative LHR grading scheme. sTIL is an independent prognostic factor for overall survival in OTSCC.

Prognostic Role of Tumor-Infiltrating Lymphocytes and Tumor Budding in Early Oral Tongue Carcinoma.

OBJECTIVES/HYPOTHESIS: Occult lymph metastasis is an important prognosticator for the treatment of early oral tongue squamous cell carcinoma (SCC). The objective of this study was to evaluate the prognostic significance of tumor-infiltrating lymphocytes (TILs) in early oral tongue SCC. The combination of the TIL subtype and intermediate- or high-grade budding scores was investigated as a prognostic marker for occult neck metastases. STUDY DESIGN: Retrospective study. METHODS: Specimens from 62 patients with early oral tongue SCC treated with only primary surgery were analyzed by immunohistochemistry for CD4+, CD8+, FoxP3+, and CD45RO+ T cells and CD163+ macrophages. The highest number of each TIL subtype was counted in two areas of parenchyma and stroma in the tumor (Tumor) and peripheral stroma of the invasion margin. RESULTS: Based on multivariate analysis, a high density of Tumor CD163+ macrophages served as the poorest prognostic factor for regional control (RC) and disease-free survival (DFS). Patients with both a high density of Tumor CD163+ macrophages and an intermediate- or a high-grade budding score had a poor prognosis for RC according to the log-rank test. CONCLUSIONS: In summary, each TIL subtype may use different mechanisms during early and advanced stages of oral tongue SCC. A high density of Tumor CD163+ macrophages was determined to be a risk factor for RC and DFS as well as an additional stratification factor for RC in patients with intermediate- or high-grade budding scores. Therefore, identifying TIL subtypes in daily clinical practice can help determine a more successful and individualized therapeutic approach for early oral tongue SCC. LEVEL OF EVIDENCE: Step 4 (Level 4) Laryngoscope, 131:2512-2518, 2021.

Evaluation Challenges in the Validation of B7-H3 as Oral Tongue Cancer Prognosticator.

B7-H3 was the only molecule identified with prognostic potential from a recent systematic review of the prognostic value of immune checkpoints in oral cancer. We aimed to validate this finding in a multicenter international cohort. We retrospectively retrieved 323 oral tongue squamous cell carcinoma (OTSCC) samples from three different countries (Brazil, Finland, and Norway) for immunostaining and scoring for B7-H3. We evaluated tumor immunogenicity by analyzing the amount of tumor-infiltrating lymphocytes and divided the tumors into immune hot and cold. To increase the reliability of the results, both digital and manual visual scoring were used. Survival curves were constructed based on the Kaplan-Meier method, and the Cox proportional hazard model was utilized for univariate and multivariate survival analysis. B7-H3 expression was not significantly associated with overall or disease-specific survival in the whole OTSCC cohort. When divided into immune hot and cold tumors, high B7-H3 expression was significantly associated with poor disease-specific and overall survival in the immune hot group, depending on the scoring method and the country of the cohort. This was achieved only in the univariate analysis. In conclusion, B7-H3 was a negative prognosticator for OTSCC patient survival in the subgroup of immune hot tumors, and was not validated as a prognosticator in the full cohort. Our findings suggest that the immune activity of the tumor should be considered when testing immune checkpoints as biomarkers.

PD-L1 expression in tongue squamous cell carcinoma.

PURPOSE: Immune checkpoint proteins programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) are important therapeutic targets for head and neck cancer. This large-scale case study aimed to analyze tongue squamous cell carcinomas (SCCs) and evaluate the correlation between PD-L1 expression and clinical prognosis. So far, this study is the largest case study on PD-L1 expression in tongue SCCs. METHODS: This is a case-control study that analyzed 121 tongue SCCs. Paraffin-embedded sections and clinical data were obtained retrospectively and immunohistochemistry with PD-L1 was performed. RESULTS: 11.6% contained ≥ 50% of PD-L1-positive cells, 57.1% of these cases had a poor prognosis with nodal metastasis. Among cases of T1/2 primary lesions with nodal metastasis, cases of high PD-L1 expression had a significantly shorter disease-free survival than cases of no PD-L1 expression (p = 0.018). The hazard ratio for high PD-L1 expression was 3.21 (95 per cent CI, 1.26-8.72) compared with no PD-L1 expression after adjusting for other factors. CONCLUSIONS: These data indicate that PD-L1 upregulation in tongue SCCs is associated with a more advanced stage and shorter disease-free survival. PD-1/PD-L1 inhibitors might hence constitute potential adjuvant therapy for tongue SCCs with PD-L1 upregulation.

Transcriptomic and Immunophenotypic Characterization of Tumor Immune Microenvironment in Squamous Cell Carcinoma of the Oral Tongue.

The tumor immune microenvironment of oral tongue squamous cell carcinoma may be accountable for differences in clinical behavior, particularly between different age groups. We performed RNA expression profiling and evaluated tumor infiltrating lymphocytes (TILs) and their T-cell subsets in order to assess the functional status of oral tongue squamous cell carcinoma tumor microenvironment and detect potentially clinically useful associations. Archival surgical pathology material from sixteen oral tongue squamous cell carcinoma patients was microscopically evaluated for TIL densities. RNA was extracted from macrodissected whole tumor sections and normal controls and RNA expression profiling was performed by the NanoString PanCancer IO 360 Gene Expression Panel. Immunostains for CD4, CD8 and FOXP3 were evaluated manually and by digital image analysis. Oral tongue squamous cell carcinomas had increased TIL densities, numerically dominated by CD4 + T cells, followed by CD8 + and FOXP3 + T cells. RNA expression profiling of tumors versus normal controls showed tumor signature upregulation in inhibitory immune signaling (CTLA4, TIGIT and PD-L2), followed by inhibitory tumor mechanisms (IDO1, TGF-ß, B7-H3 and PD-L1). Patients older than 44 years showed a tumor microenvironment with increased Tregs and CTLA4 expression. Immunohistochemically assessed CD8% correlated well with molecular signatures related to CD8 + cytotoxic T-cell functions. FOXP3% correlated significantly with CTLA4 upregulation. CTLA4 molecular signature could be predicted by FOXP3% assessed by immunohistochemistry (R2 = 0.619, p = 0.026). Oral tongue squamous cell carcinoma hosts a complex inhibitory immune microenvironment, partially reflected in immunohistochemically quantified CD8 + and FOXP3 + T-cell subsets. Immunohistochemistry can be a useful screening tool for detecting tumors with upregulated expression of the targetable molecule CTLA4.

Minimal change disease in a patient receiving checkpoint inhibition: Another possible manifestation of kidney autoimmunity?

BACKGROUND: Nivolumab has been associated with immune-related adverse events, including nephritis, with acute interstitial nephritis being the most commonly reported renal manifestation. CASE: We describe the first case to our knowledge of minimal change disease with nephrotic syndrome associated with the PD-1 checkpoint inhibitor, Nivolumab. Minimal change disease has been reported with other immune checkpoint inhibitors; however, this is the first reported case with Nivolumab. We report development of nephrotic syndrome with acute kidney injury in a 57-year-old man, 1 month after commencement of Nivolumab for metastatic squamous cell carcinoma of the tongue. Minimal change disease was confirmed by renal biopsy. Management with corticosteroids and cessation of Nivolumab failed to improve kidney function or nephrosis. CONCLUSION: This case adds to current literature identifying minimal change as an additional complication of immune checkpoint inhibitor-associated acute kidney injury. Given the increasing use of immune checkpoint inhibitors for a range of malignancies, nephrologists, oncologist and generalists should be aware of the spectrum of kidney pathologies associated with their use.

The immune phenotype of tongue squamous cell carcinoma predicts early relapse and poor prognosis.

BACKGROUND: In patients with squamous cell carcinoma of the oral tongue (OTSCC), current tumor node metastasis staging system fails to identify at-risk patients associated with early relapse and poor prognosis despite complete surgical resection. Given the importance of tumor-infiltrating lymphocytes (TILs) in the development of cancers, here we investigated the prognostic significance of the immune phenotype in OTSCC. METHODS: Hematoxylin-eosin stained sections of OTSCCs from 211 patients were evaluated. Cancers were classified as (a) immune-inflamed when TILs were found next to tumor cell nests; (b) immune-excluded when TILs were found in the stroma, outside the tumor; and (c) immune-desert for tumors lacking lymphocyte infiltrate. The prognostic significance of these immune phenotypes classes was investigated. Data were further validated on an independent cohort from The Cancer Genome Atlas database. RESULTS: Immune-desert phenotype was the least represented group of OTSCCs in our cohort (11.8%) and served as an independent prognostic factor. Patients with immune-desert tumors exhibited worse disease-specific survival (HR = 2.673; [CI: 95% 1.497-4.773]; P = .001), overall survival (HR = 2.591; [CI: 95% 1.468-4.572]; P = .001), and disease-free survival (HR = 2.313; [CI: 95% 1.118-4.786]; P = .024) at multivariate analysis. CONCLUSIONS: We identified a specific subgroup of OTSCCs with poor prognosis. Tumor-infiltrating lymphocytes density and localization could serve as an integrative parameter to the current staging system and inform the selection of most appropriate treatments. In particular, the tumor immune phenotype could improve the stratification of patients with more aggressive disease.

The differences of immunologic and TP53 mutant phenotypes between synchronous and metachronous head and neck cancer and esophageal cancer.

OBJECTIVE: To determine the tumor genomic, immunologic expression, and risk factors of treatment outcomes for patients with double head and neck squamous cell carcinoma (HNSCC) and esophageal squamous cell carcinoma (ESCC). METHODS: We reviewed patients with double HNSCC and ESCC between 1995 and 2014. The TP53 genomic mutation, CD8+ tumor infiltrating lymphocytes (TIL) and tumor programmed cell death ligand 1 (PD-L1) expression of paired HNSCC and ESCC were analyzed. RESULTS: A total of 116 patients (57 metachronous and 59 synchronous) were included. There were 88 (75.86%) patients with HNSCC and 80 (68.97%) with ESCC harboured TP53 disruptive mutation. Nearly 106 (91.38%) patients had different clonality of TP53 mutation in paired HNSCC and ESCC. The immunologic expression of synchronous and metachronous patients was significantly different. Compared to the metachronous patients, the synchronous patients had significantly higher HNSCC CD8+ TIL (p = 0.03), ESCC CD8+ TIL (p < 0.001), HNSCC PD-L1+ tumor proportion score (TPS, p = 0.04), and ESCC PD-L1+ TPS (p = 0.04). Furthermore, among the synchronous patients, the immunologic expression between HNSCC and ESCC was significantly correlated. The CD8+ TIL and PD-L1 TPS had strongly (r = 0.63, p < 0.0001) and moderately (r = 0.42, p = 0.001) positive correlations, respectively. Finally, advanced stage (III/IV) HNSCC was a significant factor for disease-free (p = 0.03) and overall survival (p = 0.005). CONCLUSION: In patients with double HNSCC and ESCC, nearly all HNSCC and ESCC were of multicentric origin. For the synchronous patients, there was more adaptive immune resistance in HNSCC and ESCC. The immunologic expression between paired HNSCC and ESCC was also significantly correlated.

A combined histo-score based on tumor differentiation and lymphocytic infiltrate is a robust prognostic marker for mobile tongue cancer.

We wanted to evaluate the prognostic value of common histopathological variables in a large cohort of patients with cancer in the mobile tongue as such information can be important for treatment stratification of the individual patient, especially for patients with low-stage disease. In addition, we wanted to investigate whether an alternative scoring model with fewer options would compromise the prognostic value. One hundred fifty patients with oral tongue squamous cell carcinomas that were treated in curative intent and with available HE-stained tumor sections were included. We reclassified all tumors and performed univariate and multivariate survival analyses of histopathological and clinical variables. For the complete cohort, lymph node status, grade of differentiation, perineural infiltration, and lymphocytic infiltration were independent prognosticators. In the low-stage disease group, independent prognostic factors were tumor size, grade of differentiation, and lymphocytic infiltrate. For patients with low-stage disease, a histo-score combining the scores for tumor differentiation and lymphocytic infiltrate identified a group of patients with particularly low survival, as patients with moderately or poorly differentiated tumors and little lymphocytic infiltrate had a less favorable 5-year survival outcome than patients in the high-stage disease group. This study shows that a histo-score combining tumor differentiation and lymphocytic infiltration should be given special consideration in treatment planning. Our results also illustrate that many variables can be scored with fewer options than previously suggested to increase their reproducibility, and still maintain their prognostic value.

Clinicopathological correlation of tumor-stroma ratio and inflammatory cell infiltrate with tumor grade and lymph node metastasis in squamous cell carcinoma of buccal mucosa and tongue in 41 cases with review of literature.

INTRODUCTION: Several studies regarding tumor-stroma ratio (TSR) in colorectal, esophageal, breast, endometrial, and cervical carcinomas have been done in the past with significant results. OBJECTIVES: The objectives of this study were to (1) study and grade TSR in buccal mucosa and tongue squamous cell carcinoma (SCC), (2) grade inflammatory cell infiltrate surrounding the tumor, and (3) correlate the above two parameters with tumor grade, lymph node metastasis, lymphovascular invasion (LVI), and perineural invasion (PNI). MATERIALS AND METHODS: Totally, 25 patients of buccal SCC and 16 cases of tongue SCC were included in the study. TSR was assessed visually on the hematoxylin and eosin-stained tissue sections by two independent observers. Cases were categorized into two groups: One with high TSR >50% (stroma poor) and the other with low TSR <50% as the stroma-rich group. TSR was correlated with tumor size, lymph node metastasis, inflammatory cell infiltrate, LVI, and PNI. Data were analyzed by the Statistical Package for the Social Sciences version 16.0 (Chicago, IL, USA) for Windows. The Chi-square and Fischer's exact tests were applied in the analysis of categorical variable. RESULTS AND CONCLUSION: SCC of buccal mucosa showed a significant correlation between TSR and size of the tumor (P = 0.001). We found that smaller the tumor size ≤2 cm (Stage T1), lesser the TSR, and size >2 cm was found to be associated with higher TSR. Hence, higher TSR (stroma poor) was associated with an adverse pathological characteristic, i.e., advanced T significantly. There was no significant correlation between TSR and inflammatory infiltrate with grade of the tumor, lymph node metastasis, LVI, and PNI. In 16 cases of SCC of the tongue; no correlation was observed between TSR and inflammatory infiltrate with tumor size, grade of the tumor, lymph node metastasis, LVI, and PNI. TSR has been studied in various malignancies (mostly adenocarcinomas) including laryngeal SCCs; however, it has never been studied on oral SCCs.

TIPE2 suppresses progression and tumorigenesis of the oral tongue squamous cell carcinoma by regulating FoxP3+ regulatory T cells.

To discover the effect of tumor necrosis factor-alpha-induced protein 8-like 2 (TIPE2) on the oral tongue squamous cell carcinoma (OTSCC) via affecting FoxP3+ regulatory T (Treg) cells. Immunohistochemistry was conducted to examine TIPE2 and FoxP3 expressions in OTSCC tumor tissues and corresponding oral mucosa. Tca8113 cells were transfected with TIPE2/control lentiviral activation particles followed by the detection with qRT-PCR, Western blotting, MTT assay, Wound healing, Transwell assay and Annexin V-FITC/PI staining. In vivo experiment was carried out on the nude mice xenografts of OTSCC with TIPE2 overexpression to observe the tumor volume and survival, and the CD4+ T cell subgroups were detected by flow cytometry. TIPE2 was lower in the OTSCC tissues than the corresponding oral mucosa, which was correlated with T stage, N stage, TNM stage, and differentiation of patients. Patients with TIPE2-positive expression had worse prognosis and lower expression of FoxP3+ Treg cells than the negative ones. Furthermore, TIPE2 overexpression curbed proliferation, invasion and migration of Tca8113 cells, while cell apoptosis was increased. Besides, TIPE2 suppressed the tumor growth and extended the survival of OTSCC mice, with the decreased proportion of FoxP3+ Treg cells in the spleen and tumor-infiltrated lymphocytes (TILs). The clinical results showed the down-regulation of TIPE2 in OTSCC tissues. Meanwhile TIPE2 overexpression affected OTSCC cells biological behavior in vitro, as well as exhibited strong tumor-growth suppressive effects in vivo, which may be a potential therapeutic target in OTSCC via regulating FoxP3+ Treg cells.

Characterization of the immune profile of oral tongue squamous cell carcinomas with advancing disease.

We investigated whether a unique immune response was instigated with the development of oral tongue squamous cell carcinomas (OTSCC), with/without nodal involvement, with/without recurrent metastatic disease, or within tumor involved nodes. One hundred and ten formalin-fixed paraffin-embedded samples were collected from a retrospective cohort of 67 OTSCC patients and 10 non-cancerous tongue samples. Targets including CD4, CD8, FOXP3, PD-L1, and PD-1 were analyzed by immunohistochemistry. The Nanostring PanCancer Immune Profiling Panel was used for gene expression profiling. Data were externally validated in the The Cancer Genome Atlas (TCGA) head and neck (HNSCC), melanoma and lung squamous cell carcinoma (LSCC) cohorts. A 24-immune gene signature was identified that discriminated more aggressive OTSCC cases, and although not prognostic in HNSCC was associated with survival in other TCGA cohorts (improved survival for melanoma, P < .001 and worse survival for LSCC, P = .038). OTSCC exhibited concordant gene and immunohistochemical (IHC) features characterized by a TH-2 biased, proinflammatory profile with upregulated B cell and neutrophil gene activity and increased CD4, FOXP3, and PD-L1 expression (P < .001 for all by IHC). Compared to less advanced disease, nodal involvement and recurrent OTSCC did not induce a different immune response although recurrent disease was characterized by significantly higher PD-L1 expression (P = .004 by SP263, P = .013 by 22C3, P = .004 for gene expression). Identification of a gene signature associated with different prognostic effects in other cancers highlights common pathways of immune dysregulation that are impacted by the tumor origin. The significant immunosuppressive signaling in OTSCC indicates primary failure of immune system to control carcinogenesis emphasizing the need for early, combination therapeutic approaches.

CA9 transcriptional expression determines prognosis and tumour grade in tongue squamous cell carcinoma patients.

CA9 is a member of the carbonic anhydrases' family, that is often expressed in cancer cells under hypoxic condition. However, the role of CA9 in the molecular mechanisms of tongue squamous cell carcinoma (TSCC) pathogenesis remains unclear. CA9 expression was analysed using the TCGA database, and its influence on survival was performed using Kaplan-Meier, LASSO and COX regression analyses. The correlation between CA9 and immune infiltration was investigated by CIBERSORT and ESTIMATE. Moreover, the relationship between CA9 expression and downstream molecular regulation pathways was analysed by GSEA, GO and WGCNA. CA9 expression correlated with clinical prognosis and tumour grade in TSCC. Moreover, CA9 expression potentially contributes to the regulation of cancer cell differentiation and mediates tumour-associated genes and signalling pathways, including apoptosis, hypoxia, G2M checkpoint, PI3K/AKR/mTOR signalling and TGF-beta signalling pathways. However, the follicular helper T cells, regulatory T cells, immune and stromal scores showed no significance between high and low CA9 expression groups. These findings suggested that CA9 plays a critical role of TSCC prognosis and tumour grade. CA9 expression significantly correlated with the regulation of cell differentiation, various oncogenes and cancer-associated pathways.

Orthotopic tongue squamous cell carcinoma (SCC) model exhibiting a different tumor-infiltrating T-cell status with margin-restricted CD8+ T cells and regulatory T cell-dominance, compared to skin SCC.

The immunological, and especially T cell, status of the tumor microenvironment affects tumor development and the efficacy of cancer treatment. To devise suitable combination therapies based on the results of murine tumor models, a more realistic orthotopic model is required. In this study, we generated a murine model of tongue squamous cell carcinoma (SCC), in which the tumor-immune cell interactions were recapitulated, and examined tumor- and T-cell status compared to a skin-transplanted SCC model by multiplex immunofluorescence staining for epidermal growth factor receptor, CD31, CD8, CD4, and Foxp3. Administration of SCCVII cells did not induce undesirable tissue damage or inflammation. In tongue SCC, abundant T-cell infiltration was observed at the tumor margin, but not in the core. Tongue SCC predominantly showed CD8+ T or Foxp3+ regulatory T cell (Treg)-infiltration. In contrast, skin-transplanted SCC showed abundant infiltration of T cells in the whole tumor area, which was dominated by Tregs. An orthotopic tongue SCC model showed differences in tumor and T-cell status compared to the skin-transplanted SCC model. Our tongue SCC model may enhance understanding of tumor-host interactions and enable evaluation of therapeutic efficacy.

Immunohistochemical Study of PD-1/PD-L1 Axis Expression in Oral Tongue Squamous Cell Carcinomas: Effect of Neoadjuvant Chemotherapy on Local Recurrence.

While neoadjuvant chemotherapy (NAC) for patients with oral tongue squamous cell carcinoma (OTSCC) may improve tumor microenvironment, it may lead to local immune suppression caused by residual cancer cells. The efficacy of NAC is therefore controversial. In our study, we investigated tumor microenvironments after NAC using immune checkpoint molecules, and evaluated the association between tumor microenvironments, clinicopathological factors and outcomes. We reviewed the records of 121 patients who underwent radical surgery for OTSCC between April 2001 and March 2015. Patients with a positive surgical margin and a follow up period of less than 6 months were excluded. For these patients, programmed death 1 (PD-1) and programmed death ligand 1 (PD-L1) expressions were immunohistochemically examined. The expression of PD-1 and PD-L1 were significantly associated with local recurrence in patients with OTSCC (P < 0.01 and P < 0.01, respectively). We found a significant decrease in 5-year disease specific survival rate for patients with combined PD-1+/PD-L1+ expressions (P < 0.05). In the subgroup analysis of local recurrence between the NAC treated group and those who received surgery alone, high levels of PD-1 and PD-L1 expressions were significantly found in the former, but not in the latter group. Local recurrence in the NAC-treated group may contribute to local immune suppression in OTSCC. NAC lead to local immune suppression and immune checkpoint molecules play an important role in local recurrence in patients with OTSCC who received NAC. NAC modality can't be recommended for patients with OTSCC at present.

Tumor-Infiltrating CD1a+ DCs and CD8+/FoxP3+ Ratios Served as Predictors for Clinical Outcomes in Tongue Squamous Cell Carcinoma Patients.

Tumor-infiltrating immune cells engage in an extensive crosstalk with tumors and act as two-edged swords by inhibiting or promoting cancer growth. Therefore, identifying the density and prognostic values of tumor-infiltrating immune cells will provide valuable tips for cancer treatments. In this study, we identified the density of tumor inflammatory infiltrates and the number of tumor-infiltrating immune cells, including CD3+, CD4+, CD8+, FoxP3+ T cells and CD1a+ dendritic cells (DCs) in 153 tongue squamous cell carcinomas (TSCC). High inflammatory cell infiltration was associated with better overall survival (OS) and disease free survival (DFS). Moreover, the number of CD3+, CD4+, FoxP3+ and CD1a+ cells were associated with tumor differentiation (P<0.001) and the number of FoxP3+, CD1a+ cells and CD8+/FoxP3+ ratios were also associated with tumor stage (P<0.01, P<0.01, P<0.05). In addition, patients with higher CD1a+ DCs had better OS and increased CD8+/FoxP3+ ratios were associated with improved OS and DFS (P = 0.037; P = 0.047; P = 0.033). In conclusion, our results indicated that tumor-infiltrating CD1a+ DCs and CD8+/FoxP3+ ratios were associated with favorable clinical outcomes but not independent prognostic factors for TSCC patients.