Phenotypic characteristics of tumour-infiltrating lymphocytes in human oesophageal cancer tissues defined by quantitative two-colour analysis with flow-cytometry

PLAN B for immunotherapy: Promoting and leveraging anti-tumor B cell immunity

Current immuno-oncology primarily focuses on adaptive cellular immunity mediated by T lymphocytes. The other important lymphocytes, B cells, are largely ignored in cancer immunotherapy. B cells are generally considered to be responsible for humoral immune response to viral and bacterial infections. The role of B cells in cancer immunity has long been under debate. Recently, increasing evidence from both preclinical and clinical research has shown that B cells can also induce potent anti-cancer immunity, via humoral and cellular immune responses. Yet it is unclear how to efficiently integrate B cell immunity in cancer immunotherapy. In the current perspective, anti-tumor immunity of B cells is discussed regarding antibody production, antigen presentation, cytokine release and contribution to intratumoral tertiary lymphoid structures. Afterwards, immunosuppressive regulatory phenotypes of B cells are summarized. Furthermore, strategies to activate and modulate B cells using nanomedicines and biomaterials are discussed. This article provides a unique perspective on "PLAN B" (promoting and leveraging anti-tumor B cell immunity) using nanomedicines and biomaterials for cancer immunotherapy. This is envisaged to form a new research direction with the potential to reach the next breakthrough in immunotherapy.

Diversity and shared T-cell receptor repertoire analysis in esophageal squamous cell carcinoma

The tumor immune response is dependent on the interaction between tumor cells and the T-cell subset expressing the T-cell receptor (TCR) repertoire that infiltrates into the tumor microenvironment. The present study explored the diversity and shared TCR repertoires expressed on the surface of locoregional T cells and identified the T lymphocyte subsets infiltrating into esophageal squamous cell carcinoma (ESCC), in order to provide insight into the efficiency of immunotherapy and the development of a novel immune-oriented therapeutic strategy. A total of 53 patients with ESCC were enrolled in the present study, and immunohistochemical analysis of CD3, CD8, CD45RO, FOXP3, CD274, HLA class I and AE1/AE3 was performed. Digital pathological assessment was performed to evaluate the expression level of each marker. The clinicopathological significance of the immuno relation high (IR-Hi) group was assessed. Adaptor ligation PCR and next-generation sequencing were performed to explore the diversity of the TCR repertoire and to investigate the shared TCR repertoire in the IR-Hi group. Repertoire dissimilarity index (RDI) analysis was performed to assess the diversity of TCR, and the existence of shared TCRα and TCRβ was also investigated. Further stratification was performed according to the expression of markers of different T-cell subsets. Patients were stratified into IR-Hi and immuno relation low (IR-Lo) groups. Cancer-specific survival and recurrence-free survival rates were significantly improved in the IR-Hi group compared with in the IT-Lo group. The diversity of the TCR repertoire was significantly higher in the IR-Hi group. TCR repertoire analysis revealed 27 combinations of TCRα and 23 combinations of TCRβ VJ regions that were shared among the IR-Hi group. The IR-Hi group was divided into three clusters. Overall, the current findings revealed that the IR-Hi group maintained the diversity of TCR, and a portion of the IR-Hi cases held the T cells with shared TCR repertoires, implying recognition of shared antigens. The prognosis of patients with ESCC was affected by the existence of immune response cells and may possibly be stratified by the T-cell subsets.

Cytokine gene-mediated immunotherapy: current status and future perspectives

Recent understanding of the molecular events crucial in overcoming immunosuppressive tumor microenvironments and generating effective antitumor immunity provides us with the wreath opportunity to manipulate genes that have a key role in antitumor immune responses. Granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-12 (IL-12) are two indispensable cytokines for activating dendritic cells and boosting the strong immune responses against cancer. In this review, we describe the antitumor mechanisms and clinical application of gene-modified tumor cells and dendritic cells to secrete GM-CSF or IL-12, respectively, in various preclinical and clinical settings. The principles operative in these vaccination strategies may prove applicable to other immunotherapy strategies, especially in combination with other therapeutic modalities, such as chemotherapy and targeted therapy.

Spontaneous regression of neoplasms: new possibilities for immunotherapy

In mammalian cells, neoplastic transformation is directly associated with the expression of oncogenes, loss or simple inactivation of the function of tumour suppressor genes and the production of certain growth factors. Genes for suppression of the development of the neoplastic cellular immunophenotype, as well as inhibitory growth factors, have regulatory functions within the normal processes of cell division and differentiation. Telomerase (a ribonucleoprotein polymerase) activation is frequently detected in various neoplasms. Telomerase activation is regarded as essential for cell immortalisation and its inhibition may result in spontaneous regression of neoplasms. This phenomenon of neoplasms occurs when the malignant tissue mass partially or completely disappears without any treatment or as a result of a therapy considered inadequate to influence systemic neoplastic growth. This definition makes it clear that the term 'spontaneous regression' applies to neoplasms in which the overall malignant disease is not necessarily cured and to cases where the regression may not be complete or permanent. A number of possible mechanisms of spontaneous regression are reviewed, with the understanding that no single mechanism can completely account for this phenomenon. The application of the newest immunological, molecular biological and genetic insights for more individualised and adequate antineoplastic immunotherapy (alternative biotherapy) is also discussed.

Variability of neoplastic parameters in colon tumours, and its significance in diagnostic practice

We have reviewed the value of individual variability in the reaction of tissues to treatment with carcinogens, and the manifestation of this variability in different morphological (histological, morphometric, and ultrastructural), histochemical and immunohistochemical parameters generated in tumorous tissues. Moreover, we also reviewed data in the literature on individual variability in the manifestation of some biochemical and immunochemical markers which are accumulated in the serum of tumour-bearing patients and which are characteristic for the different phases of tumourigenesis. The high variability of different tumorous parameters suggests that none can be utilized alone as a conclusive marker of neoplasia and that only their combined use can give objective information. We also reviewed the impact of this variability in the evaluation of various pathological methods to detect different stages of neoplastic transformation in the colon. It has been concluded that none of the present approaches can be absolutely conclusive and without false results, and that objective information regarding early cancerous changes may be obtained only by use of combined analyses utilizing several laboratory methods. The diagnostic procedures should be based on the complex utilization of all appropriate methods using the quantitative interpretation of the obtained data. Multivariate analysis of many parameters should be very effective for the prediction of therapeutic results.

Prognostic value of DNA ploidy in squamous cell carcinoma of esophagus. Analyzed with improved flow cytometric measurement

BACKGROUND

The prognostic value of flow cytometric DNA analysis on paraffin-embedded tumor samples has been controversial in esophageal cancer. To clarify its true significance, the authors developed an improved method that excludes the possibility of contamination by lymphocytes in tumor sample.

METHODS

Single nuclear suspension was prepared from paraffin-embedded samples on 103 patients with squamous cell carcinoma of the esophagus. Both DNA content and nuclear size were simultaneously measured by flow cytometry on 30,000 nuclei, and contaminated lymphocyte nuclei were eliminated from the data by optimal gating. Correlation between DNA ploidy and postoperative survival was examined.

RESULTS

Analysis using a flow cytometric cell sorter showed that the frequency of tumor cells in the lymphocyte-reducing gating fraction (LGF) was significantly higher than that in the conventional nongating fraction (NGF). LGF analysis showed aneuploid peaks in 58 patients (56.3%), but NGF analysis showed aneuploid peaks in only 38 patients. LGF analysis revealed that the aneuploid tumors had higher histologic grading (P < 0.05) and worse survival rate (P < 0.01) compared with diploid tumors. However, conventional methods could not detect this difference.

CONCLUSIONS

Flow cytometric analysis gating by nuclear size may be helpful to detect aneuploid peaks, and for predicting prognosis of patients with squamous cell carcinoma of esophagus.

Principal lymphocyte subpopulation in local host response to human oesophageal cancer

We investigated what subpopulations of tumour-infiltrating lymphocytes (TIL) play a key role in in vivo function and what determines the degree of local host response represented by lymphocyte infiltration in human oesophageal cancer. We examined the increased subpopulation of TIL in "good responders" (GR) (patients with intensively TIL infiltrated tumours) when compared with "poor responders" (PR) (patients with weakly TIL infiltrated tumours). The frequency of each subpopulation was determined by quantitative flow-cytometric measurement on TIL separated from fresh tumours. Of TIL in GR, the frequency of CD3+ cells increased significantly (P less than 0.05) but the frequencies of CD16+, Leu7-, and CD16+ Leu7- cells were low and did not increase significantly compared with those in PR. With respect to T-cell subsets of TIL in GR, the frequency of CD8+ cells was significantly higher than that in PR (P less than 0.01), and CD4+/CD8+ ratio was lower than that in PR (P less than 0.025). On two-colour analyses, most of CD8+ cells (cytotoxic/suppressor T-cells: Tc/s) did not co-express CD11b and the frequency of CD8+ CD11b- cells (cytotoxic T-cell: Tc) increased significantly compared with that in PR. Clinicopathological and phenotypic analysis of peripheral blood lymphocytes revealed that there are no major differences in general immunocompetence between GR and PR. These results suggest that Tc/s, especially Tc, might play a key role in local host response. They also suggest that not only the general immune status of the host but also the identification of class I major histocompatibility complex antigens by the host at the tumour site may strongly affect the degree of host response in oesophageal cancer.