Lingual Denervation Improves the Efficacy of Anti-PD-1 Immunotherapy in Oral Squamous Cell Carcinomas by Downregulating TGFß Signaling.

PURPOSE: Intratumoral nerve infiltration relates to tumor progression and poor survival in oral squamous cell carcinoma (OSCC). How neural involvement regulates antitumor immunity has not been well characterized. This study aims to investigate molecular mechanisms of regulating tumor aggressiveness and impairing antitumor immunity by nerve-derived factors. EXPERIMENTAL DESIGN: We performed the surgical lingual denervation in an immunocompetent mouse OSCC model to investigate its effect on tumor growth and the efficacy of anti-PD-1 immunotherapy. A trigeminal ganglion neuron and OSCC cell coculture system was established to investigate the proliferation, migration, and invasion of tumor cells and the PD-L1 expression. Both the neuron-tumor cell coculture in vitro model and the OSCC animal model were explored. RESULTS: Lingual denervation slowed down tumor growth and improved the efficacy of anti-PD-1 treatment in the OSCC model. Coculturing with neurons not only enhanced the proliferation, migration, and invasion but also upregulated TGFß-SMAD2 signaling and PD-L1 expression of tumor cells. Treatment with the TGFß signaling inhibitor galunisertib reversed nerve-derived tumor aggressiveness and downregulated PD-L1 on tumor cells. Similarly, lingual denervation in vivo decreased TGFß and PD-L1 expression and increased CD8+ T-cell infiltration and the expression of IFNγ and TNFα within tumor. CONCLUSIONS: Neural involvement enhanced tumor aggressiveness through upregulating TGFß signaling and PD-L1 expression in OSCC, while denervation of OSCC inhibited tumor growth, downregulated TGFß signaling, enhanced activities of CD8+ T cells, and improved the efficacy of anti-PD-1 immunotherapy. This study will encourage further research focusing on denervation as a potential adjuvant therapeutic approach in OSCC. SIGNIFICANCE: This study revealed the specific mechanisms for nerve-derived cancer progression and impaired antitumor immunity in OSCC, providing a novel insight into the cancer-neuron-immune network as well as pointing the way for new strategies targeting nerve-cancer cross-talk as a potential adjuvant therapeutic approach for OSCC.

Effect of the intratumoral microbiota on spatial and cellular heterogeneity in cancer.

The tumour-associated microbiota is an intrinsic component of the tumour microenvironment across human cancer types1,2. Intratumoral host-microbiota studies have so far largely relied on bulk tissue analysis1-3, which obscures the spatial distribution and localized effect of the microbiota within tumours. Here, by applying in situ spatial-profiling technologies4 and single-cell RNA sequencing5 to oral squamous cell carcinoma and colorectal cancer, we reveal spatial, cellular and molecular host-microbe interactions. We adapted 10x Visium spatial transcriptomics to determine the identity and in situ location of intratumoral microbial communities within patient tissues. Using GeoMx digital spatial profiling6, we show that bacterial communities populate microniches that are less vascularized, highly immuno­suppressive and associated with malignant cells with lower levels of Ki-67 as compared to bacteria-negative tumour regions. We developed a single-cell RNA-sequencing method that we name INVADEseq (invasion-adhesion-directed expression sequencing) and, by applying this to patient tumours, identify cell-associated bacteria and the host cells with which they interact, as well as uncovering alterations in transcriptional pathways that are involved in inflammation, metastasis, cell dormancy and DNA repair. Through functional studies, we show that cancer cells that are infected with bacteria invade their surrounding environment as single cells and recruit myeloid cells to bacterial regions. Collectively, our data reveal that the distribution of the microbiota within a tumour is not random; instead, it is highly organized in microniches with immune and epithelial cell functions that promote cancer progression.

Tumors can teem with microbes. But what are they doing there?

New study suggests microbiomes can promote cancer by suppressing immune response and seeding metastase.

Candida albicans induces upregulation of programmed death ligand 1 in oral squamous cell carcinoma.

BACKGROUND: The potential association between Candida albicans (C. albicans) infection and oral squamous cell carcinoma (OSCC) has been noticed for a long time. Programmed death ligand-1 (PD-L1) is a key molecule of tumor immune escape and tumor progression. This study aimed to explore whether C. albicans could influence PD-L1 expression in OSCC in vitro and in mouse model. METHODS: OSCC cell lines (Cal27 and HN6) were infected with C. albicans for 2 and 24 h, then PD-L1 expression was detected by quantitative real-time polymerase chain reaction (RT-qPCR), western blot (WB), and flow cytometry (FCM). To identify the underlying mechanisms, PD-L1 expression in OSCC cells treated with heat-inactivated C. albicans or with biofilm metabolites derived from C. albicans were explored respectively. Meanwhile, signaling pathways involved in PD-L1 regulation were explored by RT-qPCR, and the candidate genes were verified by WB. Moreover, an OSCC mouse model induced by 4-nitroquinoline-1 oxide was used to further explore the role of C. albicans infection in PD-L1 expression in vivo. RESULTS: C. albicans and heat-inactivated C. albicans upregulated the PD-L1 expression in Cal27 and HN6 cells. Various signaling pathways involved in PD-L1 regulation were influenced by C. albicans infection. Among them, TLR2/MyD88 and TLR2/NF-κB pathways might participate in this process. Furthermore, PD-L1 expression in oral mucosa epithelium was upregulated by C. albicans infection in both normal and OSCC mice. CONCLUSIONS: This study suggests that C. albicans could induce upregulation of PD-L1 in OSCC in vitro and in mouse model, which might due to the activation of TLR2/MyD88 and TLR2/NF-κB pathways.

Identification of autophagy-related biomarker and analysis of immune infiltrates in oral carcinoma.

BACKGROUND: Autophagy plays a vital role in the progression of the tumor. We aimed to investigate the expression, prognostic value, and immune infiltration of autophagy-related genes in oral carcinoma via bioinformatics analysis. METHODS: The microarray datasets (GSE146483 and GSE23558) of oral carcinoma were downloaded from Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between normal and diseased groups were identified by the Limma package. The screened autophagy-related gene was further validated by the human protein atlas (HPA) database, TCGA database, and GSE78060 dataset. RESULTS: A total of 18 upregulated (top 10: EGFR, TNF, FADD, AURKA, E2F1, CHEK1, BRCA1, BIRC5, EIF2AK2, and CSF2) and 31 downregulated (top 10: MAP1LC3A, PARK2, AGT, IGF1, TP53INP1, CXCL12, IKBKB, SESN1, ULK2, and RRAGD) autophagy-related (DEGs) were identified, and FADD was found to be related to the prognosis of oral cancer patients. Gene set enrichment analysis indicated that FADD-associated genes were significantly enriched in immune-related pathways. Moreover, correlation analysis revealed that FADD expression was associated with immune infiltrates. Upregulation of FADD is associated with poor survival and immune infiltrates in oral cancer. CONCLUSION: We speculated that FADD is involved in the immune regulation of oral cancer, as well as autophagy.

Implications of Human Antimicrobial Peptide Defensin Beta-1 in Clinical Oral Squamous Cell Carcinoma Patients via an Integrated Bioinformatics Approach.

BACKGROUND: The human antimicrobial peptide defensin beta 1 (DEFB1) has been found to play antimicrobial and anti-inflammatory roles in oral diseases; however, its tumor-regulating role in oral squamous cell carcinoma (OSCC) has not yet been researched by using an integrative bioinformatics approach. OBJECTIVE: To investigate the regulating mechanisms of the DEFB1 gene in OSCC in terms of its expression patterns, prognostic values, biological functions, and implication for tumor immunity. METHODS: The DEFB1 gene expression pattern and regulatory involvement in OSCC were investigated using publically accessible data from TCGA database. R software tools and public web servers were utilized to conduct statistical analysis of data from cancer and noncancerous samples. RESULTS: DEFB1 was found to be significantly downregulated in OSCC tumor samples compared with healthy control oral samples. The DEFB1 gene was found associated with the prognostic outcomes of OSCC, and its upregulation represented better survival outcome. Gene set enrichment analysis (GSEA) results showed that DEFB1-significantly correlated genes were mainly enriched in four signaling pathways mediating the antitumor role of DEFB1 in OSCC, including extracellular matrix-related pathway, RTK/PI3K/AKT/mTOR pathway, keratinization, and cytokine-related pathway. The gene-gene interaction network showed that DEFB1 was closely correlated with several genes, for example, CCR6 (C-C motif chemokine receptor 6), CXCL1 (C-X-C motif chemokine ligand 1), MAP4K2 (mitogen-activated protein kinase kinase kinase kinase 2), PTGER3 (prostaglandin E receptor 3), and MMP7 (matrix metallopeptidase 7). Moreover, DEFB1 was found to be involved in the tumor immunity of OSCC by regulating the function of tumor macrophage cells, mast cells, T cells, and NK cells. CONCLUSIONS: Given the dysregulation, prognostic value, and tumor progression-related biological pathway alteration, indicating the tumor immune-modulatory role of DEFB1 in OSCC, the DEFB1 gene should be regarded as a potential therapeutic target for treating oral cancer.

Role of the Tumor Microenvironment and the Influence of Epigenetics on the Tumor Microenvironment in Oral Carcinogenesis: Potential Implications.

Oral cancer has become a significant problem throughout the world, particularly in countries that are still developing. Recent literature supports the contribution of components of the tumor microenvironment (TME) and the effect of epigenetic changes happening in the cells of the TME on oral cancer development and progression. In this review, we comprehensively examine the significance of TME in the development of OC along with the current understanding of the epigenetic modifications that regulate the TME and their cohesive impact on tumor traits and their potential as therapeutic targets.

Biomaterial-mediated modulation of oral microbiota synergizes with PD-1 blockade in mice with oral squamous cell carcinoma.

Because a host's immune system is affected by host-microbiota interactions, means of modulating the microbiota could be leveraged to augment the effectiveness of cancer therapies. Here we report that patients with oral squamous cell carcinoma (OSCC) whose tumours contained higher levels of bacteria of the genus Peptostreptococcus had higher probability of long-term survival. We then show that in mice with murine OSCC tumours injected with oral microbiota from patients with OSCCs, antitumour responses were enhanced by the subcutaneous delivery of an adhesive hydrogel incorporating silver nanoparticles (which inhibited the growth of bacteria competing with Peptostreptococcus) alongside the intratumoural delivery of the bacterium P. anaerobius (which upregulated the levels of Peptostreptococcus). We also show that in mice with subcutaneous or orthotopic murine OSCC tumours, combination therapy with the two components (nanoparticle-incorporating hydrogel and exogenous P. anaerobius) synergized with checkpoint inhibition with programmed death-1. Our findings suggest that biomaterials can be designed to modulate human microbiota to augment antitumour immune responses.

Repression of CRNDE enhances the anti-tumour activity of CD8 + T cells against oral squamous cell carcinoma through regulating miR-545-5p and TIM-3.

Immunotherapy has been identified a promising treatment of cancers, including Oral squamous cell carcinoma (OSCC). CRNDE is highly overexpressed in various cancers. Many lncRNAs have been reported in CD8 T lymphocytes. Little is investigated about their effects in the functions of CD8 + T cells in OSCC. Currently, the influence of lncRNA CRNDE on the function of CD8 + T cells in OSCC progression was investigated. Here, CRNDE was obviously elevated and negatively correlated with IFN-γ production in tumour-infiltrating CD8 + T cells isolated from OSCC patients. CRNDE can exhibit a crucial role in activating CD8 + T-cell exhaustion. Mechanistically, CRNDE specifically sponged miR-545-5p to induce T-cell immunoglobulin and mucin domain-3 (TIM-3), thus contributing to CD8 + T-cell exhaustion. The function of miR-545-5p on T-cell function remains poorly known. TIM-3 is a significant immune checkpoint, and it inhibits cancer immunity. TIM-3 can demonstrate an important role in CD8 + T-cell exhaustion. In summary, loss of CRNDE could induce miR-545-5p and inhibit TIM3 expression, thus significantly activated the anti-tumour effect of CD8 + T cells.

Response and recurrence correlates in individuals treated with neoadjuvant anti-PD-1 therapy for resectable oral cavity squamous cell carcinoma.

Neoadjuvant PD-1 blockade may be efficacious in some individuals with high-risk, resectable oral cavity head and neck cancer. To explore correlates of response patterns to neoadjuvant nivolumab treatment and post-surgical recurrences, we analyzed longitudinal tumor and blood samples in a cohort of 12 individuals displaying 33% responsiveness. Pretreatment tumor-based detection of FLT4 mutations and PTEN signature enrichment favors response, and high tumor mutational burden improves recurrence-free survival. In contrast, preexisting and/or acquired mutations (in CDKN2A, YAP1, or JAK2) correlate with innate resistance and/or tumor recurrence. Immunologically, tumor response after therapy entails T cell receptor repertoire diversification in peripheral blood and intratumoral expansion of preexisting T cell clones. A high ratio of regulatory T to T helper 17 cells in pretreatment blood predicts low T cell receptor repertoire diversity in pretreatment blood, a low cytolytic T cell signature in pretreatment tumors, and innate resistance. Our study provides a molecular framework to advance neoadjuvant anti-PD-1 therapy for individuals with resectable head and neck cancer.

Neoadjuvant presurgical PD-1 inhibition in oral cavity squamous cell carcinoma.

Oral cavity squamous cell carcinoma (OCSCC) is a prevalent surgically treated subset of head and neck cancer with frequent recurrence and poor survival. Immunotherapy has demonstrated efficacy in recurrent/metastatic head and neck cancer. However, whether antitumor responses could be fostered by neoadjuvant presurgical immunotherapy remains unclear. Using a Simon's two-stage design, we present results of a single-arm phase-II trial where 12 patients with stage II-IVA OCSCC received 3 to 4 biweekly doses of 3 mg/kg nivolumab followed by definitive surgical resection with curative intent. Presurgical nivolumab therapy in this cohort shows an overall response rate of 33% (n = 4 patients; 95% CI: 12%-53%). With a median follow up of 2.23 years, 10 out of 12 treated patients remain alive. Neoadjuvant nivolumab is safe, well-tolerated, and is not associated with delays in definitive surgical treatment in this study. This work demonstrates feasibility and safety for incorporation of nivolumab in the neoadjuvant setting for OCSCC (ClinicalTrials.gov: NCT03021993).

Characterization of Cancer Stem Cell Characteristics and Development of a Prognostic Stemness Index Cell-Related Signature in Oral Squamous Cell Carcinoma.

OBJECTIVE: Cancer stem cells (CSCs) with self-renewal and plasticity contribute to tumor initiation and progression. This study developed an mRNA expression-based stemness index- (mRNAsi-) associated signature and validated biological functions of stem cell-related genes in oral squamous cell carcinoma (OSCC). METHODS: Here, mRNAsi was measured for OSCC samples from TCGA cohort, and prognosis and tumor microenvironment (stromal/immune scores, tumor purity) in high- and low-mRNAsi samples were evaluated with survival analyses and ESTIMATE algorithm. Based on prognostic mRNAsi-related genes, a risk score model was constructed by the LASSO method. The predictive accuracy was evaluated by uni- and multivariate Cox analyses and ROC curves. Among the genes in the model, the functions of H2AFZ on proliferation, apoptosis, invasion, and EMT were investigated in OSCC cells. RESULTS: High mRNAsi was distinctly associated with undesirable prognosis, increased stromal and immune scores, and lowered tumor purity. The mRNAsi-associated signature containing 11 genes was developed, and high-risk score was distinctly related to poor survival outcomes. Moreover, this signature was an independent and robust risk factor. H2AFZ upregulation significantly enhanced proliferative and invasive capacities and facilitated EMT as well as lowered apoptotic levels in Cal-27 and HSC-3 cells. CONCLUSION: Our study characterized cancer stem cell characteristics that were closely related to tumor microenvironment and developed a stemness index cell-related signature that could assist prognosis prediction and risk stratification for OSCC. H2AFZ could become a potential therapeutic target against OSCC.

Effector T cell responses unleashed by regulatory T cell ablation exacerbate oral squamous cell carcinoma.

Immune suppression by CD4+FOXP3+ regulatory T (Treg) cells and tumor infiltration by CD8+ effector T cells represent two major factors impacting response to cancer immunotherapy. Using deconvolution-based transcriptional profiling of human papilloma virus (HPV)-negative oral squamous cell carcinomas (OSCCs) and other solid cancers, we demonstrate that the density of Treg cells does not correlate with that of CD8+ T cells in many tumors, revealing polarized clusters enriched for either CD8+ T cells or CD4+ Treg and conventional T cells. In a mouse model of carcinogen-induced OSCC characterized by CD4+ T cell enrichment, late-stage Treg cell ablation triggers increased densities of both CD4+ and CD8+ effector T cells within oral lesions. Notably, this intervention does not induce tumor regression but instead induces rapid emergence of invasive OSCCs via an effector T cell-dependent process. Thus, induction of a T cell-inflamed phenotype via therapeutic manipulation of Treg cells may trigger unexpected tumor-promoting effects in OSCC.

Germline determinants of humoral immune response to HPV-16 protect against oropharyngeal cancer.

Although several oropharyngeal cancer (OPC) susceptibility loci have been identified, most previous studies lacked detailed information on human papillomavirus (HPV) status. We conduct a genome-wide analysis by HPV16 serology status in 4,002 oral cancer cases (OPC and oral cavity cancer (OCC)) and 5,256 controls. We detect four susceptibility loci pointing to a distinct genetic predisposition by HPV status. Our most notable finding in the HLA region, that is now confirmed to be specific of HPV(+)OPC risk, reveal two independent loci with strong protective effects, one refining the previously reported HLA class II haplotype association. Antibody levels against HPV16 viral proteins strongly implicate the protective HLA variants as major determinants of humoral response against L1 capsid protein or E6 oncoprotein suggesting a natural immune response against HPV(+)OPC promoted by HLA variants. This indicates that therapeutic vaccines that target E6 and attenuate viral response after established HPV infections might protect against HPV(+)OPC.

PD-L1-Mediated Immunosuppression in Oral Squamous Cell Carcinoma: Relationship With Macrophage Infiltration and Epithelial to Mesenchymal Transition Markers.

To date, immune check-point inhibitors (ICIs), particularly inhibitors of programmed cell death-1 (PD-1) and PD ligand-1 (PD-L1) have become prominent in cancer treatment and also improved life expectancy of cancer patients. As key regulators of PD-1/PD-L1 axis, the recruitment of tumor-associated macrophages (TAMs) enhances aggressive and invasive properties of tumors in immunosuppressive tumor microenvironment (TME) and promotes epithelial-mesenchymal transition (EMT). The aims of the study were first to characterize the critical links among PD-L1, TME and EMT process and, further, to explore the sensitivity of different chemical agents to different PD-L1 expression groups. Bioinformatical analysis revealed that PD-L1 was highly expressed in OSCC and higher PD-L1 expression correlated with worse survival in patients. Notably, PD-L1 was positively correlated with macrophages infiltration and EMT markers gene expression. Moreover, patients in the PD-L1high group were at a significant chance of benefiting from ICI treatment and they also showed higher sensitivity to the chemical drugs (olaparib, paclitaxel, docetaxel, and pazopanib). These findings implicate PD-L1 could serve as a novel target for prognostic and therapeutic approaches in OSCC patients; PD-L1-mediated immune evasion might be attributable to the infiltration of macrophages, resulting EMT progress; Chemical agents in combination with PD-L1 inhibitor could be served as personalized treatment plan for OSCC patients so as to maximize patient benefit.

Prognostic Value of CD45Ro+ T-Cell Expression in Patients With Oral Squamous Cell Carcinoma.

BACKGROUND/AIM: The role of tumour-infiltrating CD45Ro+ T-cells in oral squamous cell carcinoma (OSCC) is unclear. This study aimed to evaluate prognostic biomarkers for OSCC. PATIENTS AND METHODS: We determined the density of tumour-infiltrating CD45Ro+ T cells in the parenchyma and stroma at the tumour centre (TCe) and invasive front (IF) and examined the association between the density of these cells and histopathological status in 142 patients. RESULTS: Five-year overall survival (OS) and recurrence-free survival were favourable in patients with high CD45Ro+ T-cell density in the TCe stroma. OS was favourable in patients with high CD45Ro+ T-cell density in the IF stroma. Stepwise Cox regression model analysis indicated that CD45Ro+ T-cells in the stroma of the IF and TCe were an independent prognostic factor for OS. CONCLUSION: CD45Ro+ T-cells in the stroma of the IF and TCe play a role in cancer immune surveillance and may be a useful prognostic factor.

Identification of Immune-Related Risk Signatures for the Prognostic Prediction in Oral Squamous Cell Carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer, which remains a major cause of morbidity and mortality in patients with head and neck cancers. However, the critical immune-related signatures and their prognostic values have rarely been investigated. MATERIALS AND METHODS: Gene differential analysis was used to measure the differences of gene expression between the groups. Correlation analysis was used to assess the association between the gene expression levels and immune-related risk score/DNA methylation levels. The gene set enrichment analysis (GSEA) was used to identify the pathways or cell types enriched by those identified differentially expressed genes (DEGs). RESULTS: In this study, we identified four immune-related gene signatures, including CTSG, TNFRSF4, LCORL, and PLAU, that were significantly associated with the overall survival in OSCC patients from the Cancer Genome Atlas (TCGA) OSCC cohort. Moreover, these four immune-related signatures were differentially expressed between the OSCC and nontumor tissues. The two groups (high and low risk) stratified by the immune-related risk scores had significantly different OS and mortality rates. The gene expression patterns and prognostic values of these immune-related signatures were also verified in two independent validation cohorts. Furthermore, the downregulated genes in the high-risk group (which were also upregulated in the low-risk group) were significantly enriched in the cell type-specific signatures of type 2 T helper cell (Th2), plasmacytoid dendritic cell (pDC), and memory B cell. In contrast, the upregulated genes in the high-score group were enriched in growth factor receptor-related signaling pathways, such as the VEGFA-VEGFR2 signaling pathway, PI3K-Akt signaling pathway, focal adhesion-PI3K-Akt-mTOR signaling pathway, and PDGF pathway, suggesting that those pathways were inversely correlated with immune cell infiltration. CONCLUSION: In summary, the immune-related signatures had the potential for predicting the risk of OSCC patients. Moreover, the present study also improved our understanding of the association between the growth factor receptor pathways and immune cell infiltration in OSCC.

Transcutaneous Carbon Dioxide Decreases Immunosuppressive Factors in Squamous Cell Carcinoma In Vivo.

INTRODUCTION: In recent years, the tumour immunosuppressive mechanism has attracted attention as a cause of tumour chemoresistance. Although chemoresistance and immunosuppression of tumours have been reported to be associated with a hypoxic environment, effective treatments to improve hypoxia in tumours have not yet been established. We have previously applied carbon dioxide (CO2) to squamous cell carcinoma and have shown that improvement in local oxygenation has an antitumour effect. However, the effects of local CO2 administration on tumour immunosuppression, chemoresistance, and combination with chemotherapy are unknown. In this study, we investigated the effects of local CO2 administration on squamous cell carcinoma and the effects of combined use with chemotherapy, focusing on the effects on tumour immunosuppressive factors. METHODS: Human oral squamous cell carcinoma (HSC-3) was transplanted subcutaneously into the back of a nude mouse, and CO2 and cisplatin were administered. After administration twice a week for a total of 4 times, tumours were collected and the expression of tumour immunosuppressive factors (PD-L1, PD-L2, and galectin-9) was evaluated using real-time polymerase chain reaction and immunostaining. RESULTS: Compared with the control group, a significant decrease in the mRNA expression of PD-L1 was observed in both, CO2-treated and combination groups. Similarly, the expression of PD-L2 and galectin-9 decreased in the CO2-treated and combination groups. Furthermore, immunostaining also showed a significant decrease in the protein expression of tumour immunosuppressive factors in the CO2-treated and combination groups. CONCLUSION: It was confirmed that the tumour immunosuppressive factors decreased due to local CO2 administration to the mouse model. CO2 administration has the potential to improve the hypoxic environment in tumours, and combined use with chemotherapy may also improve tumour immunosuppression.

Hyperion Image Analysis Depicts a Preliminary Landscape of Tumor Immune Microenvironment in OSCC with Lymph Node Metastasis.

BACKGROUND: Oral squamous cell carcinoma (OSCC) constitutes the most common types of oral cancer. Because its prognosis varies significantly, identification of a tumor immune microenvironment could be a critical tool for treatment planning and predicting a more accurate prognosis. This study is aimed at utilizing the Hyperion imaging system to depict a preliminary landscape of the tumor immune microenvironment in OSCC with lymph node metastasis. METHODS: We collected neoplasm samples from OSCC patients. Their formalin-fixed, paraffin-embedded (FFPE) tissue sections were obtained and stained utilizing a panel of 26 clinically relevant metal-conjugated antibodies. Detection and analysis were performed for these stained cells with the Hyperion imaging system. RESULTS: Four patients met our inclusion criteria. We depicted a preliminary landscape of their tumor immune microenvironment and identified 25 distinct immune cell subsets from these OSCC patients based on phenotypic similarity. All these patients had decreased expression of CD8+ T cells in tumor specimens. Variety in cell subsets was seen, and more immune activated cells were found in patient A and patient B than those in patient C and patient D. Such differences in tumor immune microenvironments can contribute to forecasting of individual prognoses. CONCLUSION: The Hyperion imaging system helped to delineate a preliminary and multidimensional landscape of the tumor immune microenvironment in OSCC with lymph node metastasis and provided insights into the influence of the immune microenvironment in determination of prognoses. These results reveal possible contributory factors behind different prognoses of OSCC patients with lymph node metastasis and provide reference for individual treatment planning.

MPI-based bioinformatic analysis and co-inhibitory therapy with mannose for oral squamous cell carcinoma.

Mannose induces tumor cell apoptosis and inhibits glucose metabolism by accumulating intracellularly as mannose 6-phosphate while the drug sensitivity of tumors is negatively correlated with mannose phosphate isomerase gene (MPI) expression. In this study, we performed a first attempt to explore the relationship between the targeted gene MPI and immune infiltration and genetic and clinical characteristics of head and neck squamous carcinoma (HNSC) using computational algorithms and bioinformatic analysis, and further to verify the co-inhibition effects of mannose with genotoxicity, immune responses, and microbes dysbiosis in oral squamous cell carcinoma (OSCC) in vitro and in vivo. Our results found that patients with lower MPI expression had higher survival rate. The enhancement of MPI expression was in response to DNA damage gene, and ATM inhibitor was verified as a potential drug with a synergistic effect with mannose on HSC-3. In the HNSC, infiltrated immunocytes CD8+ T cell and B cell were the significantly reduced risk cells, while IL-22 and IFN-γ showed negative correlation with MPI. Finally, mannose could reverse immunophenotyping caused by antibiotics in mice, resulting in the decrease of CD8+ T cells and increase of myeloid-derived suppressor cells (MDSCs). In conclusion, the MPI gene showed a significant correlation with immune infiltration and genetic and clinical characteristics of HNSC. The treatment of ATM inhibitor, immune regulating cells of CD8+ T cells and MDSCs, and oral microbiomes in combination with mannose could exhibit co-inhibitory therapeutic effect for OSCC.