Blockade of PD-1 and LAG-3 expression on CD8+ T cells promotes the tumoricidal effects of CD8+ T cells

Immune checkpoints in B-cell Lymphoma: Still an Unmet challenge from Basic research to clinical practice

In the last decade, advancements in immunotherapy knowledge have highlighted CTLA-4, PD-1, LAG-3, TIM-3, and TIGIT, decisive immune checkpoints exhibiting within the tumor microenvironment (TME), as fundamental objects for cancer immunotherapy. The widespread clinical use of immune checkpoint inhibitors (ICls), employing PD-1/PD-L1 or CTLA-4 antibodies to obstruct crucial checkpoint regulators, is noted in treating B-cell lymphoma patients. Nevertheless, the prolonged advantages of the currently employed treatments against CTLA-4, PD-1, and PD-L1 are uncommon among patients. Thus, recent focus has been progressively moved to additional immune checkpoints on T cells, like LAG-3, TIM-3, and TIGIT, which are now seen as reassuring targets for treatment and broadly acknowledged. There are several types of immunecheckpoint molecules expressed by T cells, and inhibitors targeting immune checkpoints can revive and amplify the immune response of T lymphocytes against tumors, a crucial aspect in lymphoma therapy. However, there is little knowledge about their regulation. Herein, we discuss the anti-tumor effects and functions of ICIs in controlling T-cell activity, as well as the progress in combined application with other immunotherapies.

Increased Co-Expression of PD-L1 and CTLA-4 Predicts Poor Overall Survival in Patients with Acute Myeloid Leukemia Following Allogeneic Hematopoietic Stem Cell Transplantation

Purpose

Our previous study has demonstrated that high expression of immune checkpoints (ICs) was significantly associated with adverse clinical outcomes in patients with acute myeloid leukemia (AML). This study aims to investigate the significance of the alteration of IC co-expression for evaluating the prognosis of AML patients following allogeneic hematopoietic stem cell transplantation (allo-HSCT).

Patients and Methods

Quantitative real-time PCR (qRT-PCR) data of bone marrow (BM) samples from 62 de novo AML patients, including 37 patients who received allo-HSCT and 25 patients who received chemotherapy only, were used for prognostic analysis.

Results

High expression of PD-1, PD-L1, PD-L2, CTLA-4, and LAG-3 was associated with poor overall survival (OS) in AML patients receiving allo-HSCT, while the expression levels of PD-1, PD-L2, CTLA-4, and LAG-3, other than PD-L1, were not significantly correlated with OS in AML patients receiving chemotherapy. Importantly, PD-L1/CTLA-4 was the best combination model for predicting poor OS in AML patients following allo-HSCT, especially combined with minimal residual disease (MRD).

Conclusion

High expression of ICs in BM of AML patients following allo-HSCT was related to poor outcomes, and increasing co-expression of PD-L1 and CTLA-4 might be one of the best immune biomarkers to predict outcomes in patients with AML.

Correlation between immune microenvironment and clinicopathological characteristics and prognosis of primary large B-cell lymphoma of immune-privileged sites

OBJECTIVES

To explore the correlation between tumor-associated macrophages (TAMs), tumor-infiltrating lymphocytes (TILs), and tumor-associated angiogenesis (TAA) in the tumor microenvironment with the clinicopathological characteristics and prognosis of primary large B-cell lymphoma of immune-privileged sites (LBCL-IP).

METHODS

A total of 46 cases of LBCL-IP from the Department of Pathology, the Third Affiliated Hospital of Xinjiang Medical University, from January 2010 to February 2024, were collected, along with clinical and follow-up data of LBCL-IP patients. Immunohistochemistry and triple immunofluorescence were used to detect related proteins of TAMs, TILs, and TAA, and to analyze the correlation between TAMs, TILs, TAA, and the polarization of TAMs with the clinical and prognostic factors of LBCL-IP patients.

RESULTS

There are 30 cases (65.2 %) showed high expression of CD68 proteins, 32 cases (69.6 %) showed high expression of CD163 proteins, 19 cases (41.3 %) showed high expression of CD4 proteins, 34 cases (73.9 %) showed high expression of CD8 proteins, and 25 cases (54.3 %) showed high expression of CD34 proteins. A total of 28 cases (60.9 %) showed CD68+CD163+/CD68+CD86+≥1. The chi-square tests showed that high expression of CD163 proteins was positively correlated with elevated LDH and BMG values, and the count of CD68+CD163+/CD68+CD86+≥1 was positively correlated with ECOG scores ≥2, Ann Arbor staging III-IV, and increased BMG value. High expression of CD8 proteins was positively correlated with a Ki-67 proliferation index ≥70 %, and high MVD values were positively correlated with Ann Arbor staging III-IV. The Kaplan-Meier estimator analysis showed that LBCL-IP patients with low expression of CD68 proteins, high expression of CD163 proteins, CD68+CD163+/CD68+CD86+≥1, low expression of CD8 proteins, high MVD values, ECOG scores ≥2, Ann Arbor staging III-IV, LDH ≥250 U/L, BMG ≥2.2 mg/L, and IPI scores ≥2 had shorter survival times. Multivariate Cox regression analysis showed that low expression of CD8 proteins, CD68+CD163+/CD68+CD86+≥1, LDH ≥250 U/L, and ECOG scores ≥2 are independent risk factors affecting the survival of LBCL-IP patients.

CONCLUSION

M2-polarized TAMs and low infiltration of CD8+ TILs were more strongly correlated with poor clinical pathological indicators and worse prognosis, and MVD values may serve as an aiding means for the diagnosis and prognostic prediction of LBCL-IP disease.

GBM immunotherapy: Exploring molecular and clinical frontiers

GBM is the most common, aggressive, and intracranial primary brain tumor; it originates from the glial progenitor cells, has poor overall survival (OS), and has limited treatment options. In this decade, GBM immunotherapy is in trend and preferred over several conventional therapies, due to their better patient survival outcome. This review explores the clinical trials of several immunotherapeutic approaches (immune checkpoint blockers (ICBs), CAR T-cell therapy, cancer vaccines, and adoptive cell therapy) with their efficacy and safety. Despite significant progress, several challenges (viz., immunosuppressive microenvironment, heterogeneity, and blood-brain barrier (BBB)) were experienced that hamper their immunotherapeutic potential. Furthermore, these challenges were clinically studied to be resolved by multiple combinatorial approaches, discussed in the later part of the review. Thus, this review suggests the clinical use and potential of immunotherapy in GBM and provides the holistic recent knowledge and future perspectives.

DLD is a potential therapeutic target for COVID-19 infection in diffuse large B-cell lymphoma patients

Since the discovery of copper induces cell death(cuprotosis) in 2022, it has been one of the biggest research hotspots. cuprotosis related genes (CRGs) has been demonstrated to be a potential therapeutic target for cancer, however, the molecular mechanism of CRGs in coronavirus disease 2019 (COVID-19) infected in DLBCL patients has not been reported yet. Therefore, our research objective is first to elucidate the mechanism and role of CRGs in COVID-19. Secondly, we conducted univariate and multivariate analysis and machine learning to screen for CRGs with common expression differences in COVID-19 and DLBCL. Finally, the functional role and immune mechanism of genes in DLBCL were confirmed through cell experiments and immune analysis. The research results show that CRGs play an important role in the occurrence and development of COVID-19. Univariate analysis and machine learning confirm that dihydrolipoamide dehydrogenase (DLD) is the common key gene of COVID-19 and DLBCL. Inhibiting the expression of DLD can significantly inhibit the cycle progression and promote cell apoptosis of DLBCL cells and can target positive regulation of Lysine-specific demethylase 1 (LSD1, also known as KDM1A) to inhibit the proliferation of DLBCL cells and promote cell apoptosis. The immune analysis results show that high-expression of DLD may reduce T cell-mediated anti-tumor immunity by regulating immune infiltration of CD8 + T cells and positively regulating immune checkpoints LAG3 and CD276. Reducing the expression of DLD can effectively enhance T cell-mediated anti-tumor immunity, thereby clearing cancer cells and preventing cancer growth. In conclusion, DLD may be a potential therapeutic target for COVID-19 infection in DLBCL patients. Our research provides a theoretical basis for improving the clinical treatment of COVID-19 infection in DLBCL.

Association of CD8+TILs co-expressing granzyme A and interferon-γ with colon cancer cells in the tumor microenvironment

CD8+T cells secreting granzyme A (GZMA) can induce pyroptosis in tumor cells by effectively cleaving gasdermin B (GSDMB), which is stimulated by interferon-γ (IFN-γ). However, the interaction between GZMA-expressing CD8+T cells and GSDMB-expressing tumor cells in colon cancer remains poorly understood. Our research employed multi-color immunohistochemistry (mIHC) staining and integrated clinical data to explore the spatial distribution and clinical relevance of GZMA- and IFN-γ-expressing CD8+ tumor-infiltrating lymphocytes (TILs), as well as GSDMB-expressing CK+ cells, within the tumor microenvironment (TME) of human colon cancer samples. Additionally, we utilizing single-cell RNA sequencing (scRNA-seq) data to examine the functional dynamics and interactions among these cell populations. scRNA-seq analysis of colorectal cancer (CRC) tissues revealed that CD8+TILs co-expressed GZMA and IFN-γ, but not other cell types. Our mIHC staining results indicated that a significant reduction in the infiltration of GZMA+IFN-γ+CD8+TILs in colon cancer patients (P < 0.01). Functional analysis results indicated that GZMA+IFN-γ+CD8+TILs demonstrated enhanced activation and effector functions compared to other CD8+TIL subsets. Furthermore, GSDMB-expressing CK+ cells exhibited augmented immunogenicity. Correlation analysis highlighted a positive association between GSDMB+CK+ cells and GZMA+IFN-γ+CD8+TILs (r = 0.221, P = 0.033). Analysis of cell-cell interactions further showed that these interactions were mediated by IFN-γ and transforming growth factor-β (TGF-β), the co-stimulatory molecule ICOS, and immune checkpoint molecules TIGIT and TIM-3. These findings suggested that GZMA+IFN-γ+CD8+TILs modulating GSDMB-expressing tumor cells, significantly impacted the immune microenvironment and patients' prognosis in colon cancer. By elucidating these mechanisms, our present study aims to provide novel insights for the advancement of immunotherapeutic strategies in colon cancer.

Unraveling the Immune Microenvironment in Diffuse Large B-Cell Lymphoma: Prognostic and Potential Therapeutic Implications

Diffuse large B cell lymphoma (DLBCL) is a multifaceted condition characterized by significant diversity in its molecular and pathological subtypes and clinical manifestation. Despite the progress made in the treatment of DLBCL through the development of novel drugs, an estimated one-third of patients encounter relapse or acquire refractory disease. The tumor microenvironment (TME) of DLBCL, a complex network consisting of cellular and noncellular components that engage in interactions with the tumor, is a parameter that is gaining increasing attention. The TME comprises both the immune and nonimmune microenvironments. The immune microenvironment comprises natural killer (NK) cells, dendritic cells (DCs), tumor-associated macrophages (TAMs), neutrophils, myeloid-derived suppressor cells (MDSCs), and T and B lymphocytes. The nonimmune microenvironment consists of the extracellular matrix (ECM), cancer-associated fibroblasts (CAFs), mesenchymal stromal cells, and other molecules that are secreted. Despite ongoing research, the exact impact of these components and their interaction on the progression of the disease remains elusive. A comprehensive review of significant discoveries concerning the cellular and noncellular constituents, molecular characteristics, and treatment response and prognosis of the TME in DLBCL, as well as the potential targeting of the TME with novel therapeutic approaches, is provided in this article.

Immunotherapy of Clear-Cell Renal-Cell Carcinoma

Clear-cell Renal-Cell Carcinoma (ccRCC) is the most common type of renal-cell carcinoma (RCC). In many cases, RCC patients manifest the first symptoms during the advanced stage of the disease. For this reason, immunotherapy appears to be one of the dominant treatments to achieve a resolution. In this review, we focus on the presentation of the main immune checkpoint proteins that act as negative regulators of immune responses, such as PD-1, CTLA-4, LAG-3, TIGIT, and TIM-3, and their respective inhibitors. Interleukin-2, another potential component of the treatment of ccRCC patients, has also been covered. The synergy between several immunotherapies is one of the main aspects that unites the conclusions of research in recent years. To date, the combination of several immunotherapies enhances the efficacy of a monotherapy, which often manifests important limitations. Immunotherapy aimed at restoring the anti-cancer immune response in ccRCC, involved in the recognition and elimination of cancer cells, may also be a valid solution for many other types of immunogenic tumors that are diagnosed in the final stages.

Diffuse large B-cell lymphoma: the significance of CD8+ tumor-infiltrating lymphocytes exhaustion mediated by TIM3/Galectin-9 pathway

BACKGROUND

Overexpression of T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3) is related to the exhaustion of CD8+ tumor-infiltrating lymphocytes (TILs) in diffuse large B-cell lymphoma (DLBCL). However, the mechanism of TIM3-mediated CD8+TILs exhaustion in DLBCL remains poorly understood. Therefore, we aimed to clarify the potential pathway involved in TIM3-mediated CD8+TILs exhaustion and its significance in DLBCL.

METHODS

The expression of TIM3 and its correlation with CD8+TILs exhaustion, the key ligand of TIM3, and the potential pathway of TIM3-mediated CD8+TILs exhaustion in DLBCL were analyzed using single-cell RNA sequencing and validated by RNA sequencing. The biological significance of TIM3-related pathway in DLBCL was investigated based on RNA sequencing, immunohistochemistry, and reverse transcription-quantitative polymerase chain reaction data. Finally, the possible regulatory mechanism of TIM3-related pathway in DLBCL was explored using single-cell RNA sequencing and RNA sequencing.

RESULTS

Our results demonstrated that CD8+TILs, especially the terminally exhausted state, were the major clusters that expressed TIM3 in DLBCL. Galectin-9, mainly expressed in M2 macrophages, is the key ligand of TIM3 and can induce the exhaustion of CD8+TILs through TIM3/Galectin-9 pathway. Meanwhile, high TIM3/Galectin-9 enrichment is related to immunosuppressive tumor microenvironment, severe clinical manifestations, inferior prognosis, and poor response to CHOP-based chemotherapy, and can predict the clinical efficacy of immune checkpoint blockade therapy in DLBCL. Furthermore, the TIM3/Galectin-9 enrichment in DLBCL may be regulated by the IFN-γ signaling pathway.

CONCLUSIONS

Our study highlights that TIM3/Galectin-9 pathway plays a crucial role in CD8+TILs exhaustion and the immune escape of DLBCL, which facilitates further functional studies and could provide a theoretical basis for the development of novel immunotherapy in DLBCL.