Identification of immunogenic cell death-related damage-related molecular patterns (DAMPs) to predict outcomes in patients with head and neck squamous cell carcinoma.

PURPOSE: Head and neck cancer is the sixth most common type of cancer worldwide, wherein the immune responses are closely associated with disease occurrence, development, and prognosis. Investigation of the role of immunogenic cell death-related genes (ICDGs) in adaptive immune response activation may provide cues into the mechanism underlying the outcome of HNSCC immunotherapy. METHODS: ICDGs expression patterns in HNSCC were analyzed, after which consensus clustering in HNSCC cohort conducted. A 4-gene prognostic model was constructed through LASSO and Cox regression analyses to analyze the prognostic index using the TCGA dataset, followed by validation with two GEO datasets. The distribution of immune cells and the response to immunotherapy were compared between different risk subtypes through multiple algorithms. Moreover, immunohistochemical (IHC) analyses were conducted to validate the prognostic value of HSP90AA1 as a predictor of HNSCC patient prognosis. In vitro assays were performed to further detect the effect of HSP90AA1 in the development of HNSCC. RESULTS: A novel prognostic index based on four ICDGs was constructed and proved to be useful as an independent factor of HNSCC prognosis. The risk score derived from this model grouped patients into high- and low-risk subtypes, wherein the high-risk subtype had worse survival outcomes and poorer immunotherapy response. IHC analysis validated the applicability of HSP90AA1 as a predictor of prognosis of HNSCC patients. HSP90AA1 expression in tumor cells promotes the progression of HNSCC. CONCLUSIONS: Together, these results highlight a novel four-gene prognostic signature as a valuable tool to assess survival status and prognosis of HNSCC patients.

Influence of PD-1/PD-L1 on immune microenvironment in oral leukoplakia and oral squamous cell carcinoma.

OBJECTIVE: To evaluate the relation between the expression of PD-1, PD-L1, CD3, CD8, Foxp3 and clinicopathological features in patients with oral leukoplakia (OLK) and oral squamous cell carcinomas (OSCC) as well as the malignant outcome in OLK patients, and to study the effect of PD-1 and PD-L1 on immune microenvironment in the progression of oral carcinogenesis. METHODS: We evaluated the expression of PD-1/PD-L1 and composition of CD3+ , CD8+ and Foxp3+ T lymphocytes in OLK and OSCC samples by immunohistochemical (IHC) staining and analyzed their relation with clinical information and malignant transformation in OLK patients. RESULTS: IHC staining demonstrated that the expression of PD-1 was significantly increased in the high-grade OLK group than in the low-grade OLK group, while PD-L1 was detected mainly in OSCC. The expression of CD3, CD8, and Foxp3 was found higher in the high-grade OLK group than in the low-grade OLK group, and the Foxp3+ cells were found more in the OSCC group than in the high-grade OLK group. PD-1 was significantly correlated with CD3 (p < 0.05, R = 0.52), CD8 (p < 0.05, R = 0.46), and Foxp3 (p < 0.05, R = 0.46), and the low PD-1-expression group showed a better malignant-free survival than high PD-1 expression group in the OLK (p < 0.05). CONCLUSION: The PD-1/PD-L1 may induce immune suppression in OLK and accelerate the progress of malignant transformation.

Upregulation of CSF-1 is correlated with elevated TAM infiltration and poor prognosis in oral squamous cell carcinoma.

Mounting lines of evidence indicated that the "colony stimulating factor-1 (CSF-1)/tumor-associated macrophage (TAM)" signature plays an important role in the progression, invasion and metastasis of multiple tumors. However, the potential role of CSF-1/TAM in oral squamous cell carcinoma (OSCC) remains largely unknown. In the present study, the expression of CSF-1 from 99 OSCC specimens and its correlation with clinicopathological features and patient outcomes were investigated. Meanwhile, the correlation between CSF-1 expression and TAM infiltration was also explored. To investigate the potential effect of CSF-1 on tumor growth, nude mice were subcutaneously injected with Cal27 cell line and a small molecule inhibitor of CSF-1 (BZL945). The results showed that the high expression rate of CSF-1 (52%) was found in OSCC, and the upregulation of CSF-1 was closely correlated with lymph node metastasis and clinical stage. Additionally, there was a positive correlation between a high CSF-1 level and elevated TAM infiltration. The xenograft model study showed that CSF-1 signal blockade inhibited tumor growth, with a significant synchronous decrease in CSF-1 expression and TAM infiltration. Overall, our findings indicated that CSF-1 plays a crucial role in TAMs-mediated OSCC tumor progression and invasion. The "CSF-1/TAM" signaling axis may serve as a prospective target for anti-tumor therapy of OSCC.

Upregulated LOX and increased collagen content associated with aggressive clinicopathological features and unfavorable outcome in oral squamous cell carcinoma.

OBJECTIVES: Collagen is a core protein that maintains the homeostasis of the extracellular matrix (ECM), and its dysregulation in human cancers has attracted increasing attention. In tumors, increased lysyl oxidase (LOX)-catalyzed collagen cross-linking plays a critical role in collagen dysregulation. However, the expression patterns of LOX and collagen and their clinicopathological significance in oral squamous cell carcinoma (OSCC) have not been well established. METHODS: The LOX mRNA expression in OSCC was measured by RT-PCR and bioinformatics analysis. LOX protein expression and total collagen content were identified by immunohistochemistry or Masson's trichrome staining in a retrospective cohort of primary OSCC samples, respectively. Moreover, the associations between LOX and collagen expression and various clinicopathological parameters or patient survival were assessed. RESULTS: LOX mRNA was overexpressed in OSCC samples. Higher expression of LOX, collagen content or co-overexpression of LOX and collagen was significantly associated with aggressive clinicopathological features. Importantly, aberrant expression of LOX, collagen content, or both were markedly correlated with decreased overall and disease-free survival (P < 0.05). Moreover, univariate and multivariate Cox models analyses indicated that LOX, collagen content or their combination could serve as an independent prognostic predictor for OSCC patients. ROC analysis further revealed that the combination of LOX and collagen was superior to parameter alone as a prognostic predictor. CONCLUSIONS: Our findings reveal that elevated LOX and collagen content significantly corelate with aggressiveness and worse prognosis in OSCC.

[Evaluation of the biocompatibility and cell segregation performance of acellular dermal matrix as barrier membrane on guided tissue regeneration in vitro].

PURPOSE: To investigate the proliferation of human periodontal ligament cell on acellular dermal matrix (ADM) and the epithelial cell segregation performance of ADM and evaluate the feasibility of ADM as barrier membrane of guided tissue regeneration. METHODS: Human periodontal ligament cells(HPDLCs) of the 3rd to 5th passage were seeded onto 96-well plates(with ADM and e-PTFE inside) with 2000 cells per well. The cells were cultured in Dulbecco's modified eagle medium (DMEM). The MTT colorimetric assay method was performed at day 1, 3, 5 and 7 after incubation. The optical density(OD) of each well was measured spectrophotometrically at 490 nm to monitor effects on cell proliferation. The data was analyzed using Student's t test by SPSS13.0 software package. In addition, Tca8113 cells were placed in 24-well plates (with ADM and e-PTFE inside) with 2×10(4) cells per well. The DAPI staining was done 5, 10 d after incubation. Fluorescence microscope was used to observe the number of cells which lied on the two sides of the materials. Visual field was randomly selected to record the number of cells. The cell inoculated surface was recorded as ADM group and e-PTFE group, the other surface was recorded as ADM group and e-PTFE group. Student's t test was used to analyse the cell segregation of the two membranes. RESULTS: At 3-, 5-, 7 d, the OD value of ADM group and blank control group was significantly higher than that in e-PTFE group (P<0.05), no significant difference was found between ADM group and blank control group (P>0.05). At 5-, 10 d, the cell number in ADM group was much more than that in ADM group, similar between e-PTFE group and e-PTFE group (P<0.05), while no significant difference was noted between the ADM group and e-PTFE group (P>0.05). CONCLUSIONS: ADM is more conducive to the proliferation of HPDLCs than e-PTFE, and has the similar cell segregation performance on the epithelial cells. Compared with e-PTFE, ADM is more suitable for guided periodontal tissue regeneration. Supported by Health Science and Technology Projects of Jiangsu Province(H201231) and Priority Academic Program Development of Jiangsu Higher Education Institutions (2011-137).