CCR7 Mediated Mimetic Dendritic Cell Vaccine Homing in Lymph Node for Head and Neck Squamous Cell Carcinoma Therapy

Immunotherapy has been recognized as one of the most promising treatment strategies for head and neck squamous cell carcinoma (HNSCC). As a pioneering trend of immunotherapy, dendritic cell (DC) vaccines have displayed the ability to prime an immune response, while the insufficient immunogenicity and low lymph node (LN) targeting efficiency, resulted in an unsubstantiated therapeutic efficacy in clinical trials. Herein, a hybrid nanovaccine (Hy-M-Exo) is developed via fusing tumor-derived exosome (TEX) and dendritic cell membrane vesicle (DCMV). The hybrid nanovaccine inherited the key protein for lymphatic homing, CCR7, from DCMV and demonstrated an enhanced efficiency of LN targeting. Meanwhile, the reserved tumor antigens and endogenous danger signals in the hybrid nanovaccine activated antigen presenting cells (APCs) elicited a robust T-cell response. Moreover, the nanovaccine Hy-M-Exo displayed good therapeutic efficacy in a mouse model of HNSCC. These results indicated that Hy-M-Exo is of high clinical value to serve as a feasible strategy for antitumor immunotherapy.

New insights into iNKT cells and their roles in liver diseases

Natural killer T cells (NKTs) are an important part of the immune system. Since their discovery in the 1990s, researchers have gained deeper insights into the physiology and functions of these cells in many liver diseases. NKT cells are divided into two subsets, type I and type II. Type I NKT cells are also named iNKT cells as they express a semi-invariant T cell-receptor (TCR) α chain. As part of the innate immune system, hepatic iNKT cells interact with hepatocytes, macrophages (Kupffer cells), T cells, and dendritic cells through direct cell-to-cell contact and cytokine secretion, bridging the innate and adaptive immune systems. A better understanding of hepatic iNKT cells is necessary for finding new methods of treating liver disease including autoimmune liver diseases, alcoholic liver diseases (ALDs), non-alcoholic fatty liver diseases (NAFLDs), and liver tumors. Here we summarize how iNKT cells are activated, how they interact with other cells, and how they function in the presence of liver disease.

Biological implications of the immune factors in the tumour microenvironment of oral cancer

OBJECTIVE

The objective of this review is to decipher the biological implications of the immune factors in the tumour microenvironment in oral cancer. The restoration of balance between tumour tolerance and tumour eradication by the host immune cells is critical to provide effective therapeutic strategies.

DESIGN

The specific role of the stromal and the immune components in oral cancer was reviewed with a tailored search strategy using relevant keywords. The articles were retrieved from bibliometric databases indexed in PubMed, Scopus, and Embase. An in silico analysis was performed to identify potential drug candidates for immunotherapy, by accessing the Drug-Gene Interactions Database (DGIdb) using the rDGIdb package.

RESULTS

There is compelling evidence for the role of the cellular and extracellular components of the tumour microenvironment in inducing immunosuppression and progression of oral cancer. The druggable candidates specifically targeting the immune system are a viable option in the treatment of oral cancer as they can regulate the tumour microenvironment.

CONCLUSION

A complex interaction between the tumour and the immunological microenvironment influences the disease outcome in oral cancer. Targeting specific components of the immune system might be relevant, as immunotherapy may become the new standard of care for oral cancer.

Regulatory T cells induce CD4- NKT cell anergy and suppress NKT cell cytotoxic function

BACKGROUND

Due to the strong tumoricidal activities of activated natural killer T (NKT) cells, invariant NKT cell-based immunotherapy has shown promising clinical efficacy. However, suppressive factors, such as regulatory T cells (Tregs), may be obstacles in the use of NKT cell-based cancer immunotherapy for advanced cancer patients. Here, we investigated the suppressive effects of Tregs on NKT cells and the underlying mechanisms with the aim to improve the antitumor activities of NKT cells.

METHODS

Peripheral blood samples were obtained from healthy donors, patients with benign tumors, and patients with head and neck squamous cell carcinoma (HNSCC). NKT cells, induced with α-galactosylceramide (α-GalCer), and monocyte-derived dendritic cells (DCs) were co-cultured with naïve CD4⁺ T cell-derived Tregs to investigate the mechanism of the Treg suppressive effect on NKT cell cytotoxic function. The functions and phenotypes of NKT cells were evaluated with flow cytometry and cytometric bead array.

RESULTS

Treg suppression on NKT cell function required cell-to-cell contact and was mediated via impaired DC maturation. NKT cells cultured under Treg-enriched conditions showed a decrease in CD4^- NKT cell frequency, which exert strong tumoricidal responsiveness upon α-GalCer stimulation. The same results were observed in HNSCC patients with significantly increased effector Tregs.

CONCLUSION

Tregs exert suppressive effects on NKT cell tumoricidal function by inducing more CD4^- NKT cell anergy and less CD4⁺ NKT cell anergy. Both Treg depletion and NKT cell recovery from the anergy state may be important for improving the clinical efficacy of NKT cell-based immunotherapy in patients with advanced cancers.

Prognostic role of platelet-to-lymphocyte ratio in oral cancer: A meta-analysis

BACKGROUND AND OBJECTIVE

Platelet-to-lymphocyte ratio (PLR) has been suggested to be associated with the progression of oral cancer with inconclusive results. The objective of the current study was to assess the prognostic role of oral cancer by meta-analysis.

METHOD

PubMed, EMbase(Ovid), CNKI, WanFang Data, VIP, and CBM databases were searched up to August 24, 2018. Studies investigating the association between PLR and progression of oral cancer were included. Meta-analysis was performed by using Revman 5.3 software. The protocol of the study was registered on PROSPERO (CRD42018106836).

RESULTS

A total of five studies were included in the meta-analysis. The results of the meta-analysis showed that higher PLR was associated with the poor progress of oral cancer (overall survival: OR = 2.06, 95 CI: 1.49-2.86, P < 0.0001; disease-specific survival: OR = 2.12, 95 CI: 1.59-2.82, P < 0.00001).

CONCLUSION

The current meta-analysis showed that higher PLR is a poor progression factor for oral cancer. However, larger sample, multi-center studies should be carried out in the future to validate the above conclusion.

Immune and genomic signatures in oral (head and neck) cancer

Head and neck squamous cell carcinoma (HNSCC) is responsible for a large number of deaths each year. Oral cancer is the most frequent subtype of HNSCC. Historically, oral cancer has been associated with an increase in the consumption of tobacco and alcohol products, seen especially in the Asian subcontinent. It has also been associated with infection by the human papilloma virus (HPV), particularly strain HPV16. Treatment usually involves a multidisciplinary approach of surgery combined with chemotherapy and radiation. The advent of immunotherapy has broadened the scope for treatment. A better immune response to the tumour can also elicit the action of other therapeutic approaches. A heightened immune response, on the other hand, can lead to resistant tumour formation through the process of immunoediting. Molecular profiling of the tumour microenvironment (TME) can provide us with better insight into the mechanism and progression of the disease, ultimately opening up new therapeutic options. High-throughput molecular profiling techniques over the past decade have enabled us to appreciate the heterogeneity of the TME. In this review, we will be describing the clinicopathological role of the immune and genomic landscape in oral cancer. This study will update readers on the several immunological and genetic factors that can play an important function as predictive and prognostic biomarkers in various forms of head and neck cancer, with a special emphasis on oral carcinoma.

Phenotypic and Functional Characteristics of Th17 (CD4+IL17A+) Cells in Human Oral Squamous Cell Carcinoma and Its Clinical Relevance

Recent studies have suggested an important role of T helper 17 (Th17) cells in tumor biology however, their phenotypic and functional aspects are poorly understood in context with oral cancer. We therefore, investigated the various phenotypic and functional markers of Th17 cells elucidating their relevance in oral squamous cell carcinoma (OSCC). Multi-color flow cytometry (FACs) was used to analyze the frequency and different markers of circulating Th17 cells ex vivo in peripheral blood mono-nuclear cells (PBMCs) from 69 OSCC patients and 35 healthy controls. Percent Mean ± SEM of different types of cells were compared between the two groups using Mann-Whitney U test. We found significantly (p < 0.0001) increased frequency of Th17 cells in patients as compared to controls. These cells were found to express CCR6 profoundly but not CXCR4, CD62L, and CCR7 as chemokine receptors. Additionally, it expressed HLA-DR, CD69, and CD25 moderately but CD28 and CD161 highly. The cytokine profiling revealed 3 subsets namely Th17/1 (IL17A⁺IFNγ⁺), Th17/inflammatory (IL17A⁺IL8⁺), and Th17/2 (IL17A⁺IL4⁺) which were found to be elevated in patients as compared to controls. The early stage patients had a shift toward Th17/1 type and vice versa. Our results suggest that Th17 cells may have effector immune functions in oral cancer immunity through CCR6, CD161, HLA-DR, CD69, CD28 receptors and inducing Th17/1 type of cells expressing polyfunctional antitumor IFNγ cytokine. Thus, novel immune-boosting regimens based on enhancement of Th17 cells in oral cancer patients may provide therapeutic benefits in them.