Correlation between tumor infiltrating immune cells and peripheral regulatory T cell determined using methylation analyses and its prognostic significance in resected gastric cancer

A low lymphocyte-to-monocyte ratio is independently associated with early relapse (POD24) in high tumour burden follicular lymphoma: A RELEVANCE subanalysis

The peripheral blood lymphocyte-to-monocyte ratio (LMR) has been shown to predict outcomes in follicular lymphoma (FL). Among 1018 patients from the RELEVANCE trial (for previously untreated, high tumour burden FL), the median LMR was 2.5 (range, 0.3-93.5) and an LMR cut-off of 2 was mostly associated with survival end-points. Patients with an LMR ≤2 (n = 372; 37%) were older and had higher risk disease. An LMR ≤2 was associated with a shorter progression-free survival (PFS) (hazard ratio [HR] = 1.39, p = 0.002) and overall survival (OS) (HR = 1.44, p = 0.049). The association of the LMR with PFS was significant in the rituximab plus chemotherapy arm (p = 0.01) and inconclusive in the rituximab plus lenalidomide arm (p = 0.08). Within the three Follicular Lymphoma International Prognostic Index risk categories, the LMR retained its association with PFS only in the low-risk group (p = 0.03). An LMR ≤2 was also associated with a higher risk of progression of disease within 24 months of treatment initiation (univariable odds ratio (OR) = 1.84, p < 0.001; multivariable OR = 1.58, p = 0.02). In conclusion, the LMR is an easily accessible parameter informative of outcomes in FL patients in need of treatment, being especially helpful in otherwise low-risk patients. Whether the incorporation of immunomodulators such as lenalidomide will reduce its negative prognostic value needs to be further investigated.

Early CTLA4 increase in CD45+ blood cells: an emerging biomarker of atezolizumab-bevacizumab resistance and worse survival in advanced hepatocarcinoma

BACKGROUND

Advanced hepatocellular carcinoma (HCC) has a dismal prognosis; however, the introduction of atezolizumab-bevacizumab combination has improved overall survival and novel immune checkpoint inhibitors are entering the clinics. Despite more therapeutic options being available, no biomarker guides treatment choice. Indeed, tissue-based analyses and complex analytical procedures hinder clinical translation. We explored the informativeness of a simple, non-invasive, repeatable cytofluorimetric assay on peripheral blood to predict response and survival in HCC patients treated with atezolizumab-bevacizumab.

MATERIALS AND METHODS

Twenty-five cirrhotic patients, 50 HCC patients undergoing atezolizumab-bevacizumab and an independent validation cohort of 25 HCC patients were subjected to a cytofluorimetric study of peripheral white blood cells (WBCs) to assess baseline programmed death-ligand 1-positive (PD-L1+) and cytotoxic T-lymphocyte antigen 4-positive (CTLA4+) cell percentage in the different populations and their early on-treatment variations. Immunophenotypes were evaluated against treatment response. RNA sequencing followed by RT-PCR validation were used to elucidate the molecular correlates of immunophenotypic observations.

RESULTS

PD-L1+ cell percentage did not predict response either at baseline or when evaluating treatment-induced early changes. Conversely, the percentage of CTLA4+ lymphocytes at baseline showed a predictive significance (35.37 in responders versus 31.5 in non-responders, P = 0.03). More interestingly, the early CTLA4+ changes during treatment in lymphocytes (responders 0.95 versus non-responders 1.08, P = 0.05), monocytes (responders 0.95 versus non-responders 1.04, P = 0.03), granulocytes (responders 0.94 versus non-responders 1.14, P = 0.001) and, even stronger, the early CTLA4+ percentage change in the whole WBCs displayed a predictive significance in terms of time to progression (TTP) (P < 0.0001) and overall survival (OS) (P = 0.005). The immunophenotypic findings correlated with transcriptional modulation of CTLA4 target genes and genes involved in immune response.

CONCLUSIONS

A repeatable, easy, non-invasive blood test predicts response to immunotherapy in patients with HCC, both in terms of TTP and OS. CTLA4+ cell percentage increase in non-responders suggests a possible resistance mechanism which deserves attention as a druggable target.

The interaction between DNA methylation and tumor immune microenvironment: from the laboratory to clinical applications

DNA methylation is a pivotal epigenetic modification that affects gene expression. Tumor immune microenvironment (TIME) comprises diverse immune cells and stromal components, creating a complex landscape that can either promote or inhibit tumor progression. In the TIME, DNA methylation has been shown to play a critical role in influencing immune cell function and tumor immune evasion. DNA methylation regulates immune cell differentiation, immune responses, and TIME composition Targeting DNA methylation in TIME offers various potential avenues for enhancing immune cytotoxicity and reducing immunosuppression. Recent studies have demonstrated that modification of DNA methylation patterns can promote immune cell infiltration and function. However, challenges persist in understanding the precise mechanisms underlying DNA methylation in the TIME, developing selective epigenetic therapies, and effectively integrating these therapies with other antitumor strategies. In conclusion, DNA methylation of both tumor cells and immune cells interacts with the TIME, and thus affects clinical efficacy. The regulation of DNA methylation within the TIME holds significant promise for the advancement of tumor immunotherapy. Addressing these challenges is crucial for harnessing the full potential of epigenetic interventions to enhance antitumor immune responses and improve patient outcomes.

Gut microbiome-derived butyrate inhibits the immunosuppressive factors PD-L1 and IL-10 in tumor-associated macrophages in gastric cancer

Early detection and surgical treatment are essential to achieve a good outcome in gastric cancer (GC). Stage IV and recurrent GC have a poor prognosis. Therefore, new treatments for GC are needed. We investigated the intestinal microbiome of GC patients and attempted to reverse the immunosuppression of the immune and cancer cells of GC patients through the modulation of microbiome metabolites. We evaluated the levels of programmed death-ligand 1 (PD-L1) and interleukin (IL)-10 in the peripheral blood immunocytes of GC patients. Cancer tissues were obtained from patients who underwent surgical resection of GC, and stained sections of cancer tissues were visualized via confocal microscopy. The intestinal microbiome was analyzed using stool samples of healthy individuals and GC patients. Patient-derived avatar model was developed by injecting peripheral blood mononuclear cells (PBMCs) from advanced GC (AGC) patients into NSG mice, followed by injection of AGS cells. PD-L1 and IL-10 had higher expression levels in immune cells of GC patients than in those of healthy controls. The levels of immunosuppressive factors were increased in the immune and tumor cells of tumor tissues of GC patients. The abundances of Faecalibacterium and Bifidobacterium in the intestinal flora were lower in GC patients than in healthy individuals. Butyrate, a representative microbiome metabolite, suppressed the expression levels of PD-L1 and IL-10 in immune cells. In addition, the PBMCs of AGC patients showed increased levels of immunosuppressive factors in the avatar mouse model. Butyrate inhibited tumor growth in mice. Restoration of the intestinal microbiome and its metabolic functions inhibit tumor growth and reverse the immunosuppression due to increased PD-L1 and IL-10 levels in PBMCs and tumor cells of GC patients.

Detection of diagnostic and prognostic methylation-based signatures in liquid biopsy specimens from patients with meningiomas

Recurrence of meningiomas is unpredictable by current invasive methods based on surgically removed specimens. Identification of patients likely to recur using noninvasive approaches could inform treatment strategy, whether intervention or monitoring. In this study, we analyze the DNA methylation levels in blood (serum and plasma) and tissue samples from 155 meningioma patients, compared to other central nervous system tumor and non-tumor entities. We discover DNA methylation markers unique to meningiomas and use artificial intelligence to create accurate and universal models for identifying and predicting meningioma recurrence, using either blood or tissue samples. Here we show that liquid biopsy is a potential noninvasive and reliable tool for diagnosing and predicting outcomes in meningioma patients. This approach can improve personalized management strategies for these patients.

Short-term prognostic role of peripheral lymphocyte subsets in patients with gastric cancer

BACKGROUND

Immune function is associated with clinical outcomes in patients with gastric cancer. This study aimed to explore the prognostic role of peripheral lymphocyte subsets in patients with gastric cancer after curative surgery.

METHODS

This retrospective study was conducted at a single tertiary referral hospital. We included patients diagnosed with gastric cancer who had undergone surgery and met the inclusion criteria. Clinicopathological characteristics and preoperative peripheral lymphocyte subset data were collected for the analysis. Recurrence-free survival (RFS) and overall survival were analyzed using the Kaplan-Meier curve and Cox hazard regression model. We used the Whitney test and Spearman test to analyze the correlation between lymphocyte subsets and clinicopathological characteristics.

RESULTS

This study included 171 patients with gastric cancer who underwent curative surgery. Multivariate analysis revealed that carcinoembryonic antigen (p < 0.01), carbohydrate antigen 19-9 (p < 0.001), lymph node metastases (p < 0.001), total T-cell count (p = 0.02), B-cell count (p < 0.01), and regulatory T-cell percentage (p < 0.01) were independent predictive factors associated with RFS.

CONCLUSIONS

Impaired immune function may lead to early recurrence following curative surgery. Our study showed that the characteristics of peripheral lymphocyte subsets (T, B, and Treg cells) were independent predictive factors for recurrence in patients with gastric cancer after surgery.

Prognostic significances of PD-L1- and CTLA-4-positive T cells and positive correlations of immunosuppressive marker expression between cancer tissue and peripheral blood in patients with gastric cancer

Introduction

Although tumor, node, metastasis (TNM) staging has been used for prognostic assessment of gastric cancer (GC), the prognosis may vary among patients with the same TNM stage. Recently, the TNM-Immune (TNM-I) classification staging system has been used for prognostic assessment of colorectal cancer based on intra-tumor T-cell status, which is a superior prognostic factor compared with the American Joint Committee on Cancer staging manual. However, an immunoscoring system with prognostic significance for GC has not been established.

Method

Here, we evaluated immune phenotypes in cancer and normal tissues, then examined correlations between tissues and peripheral blood. GC patients who underwent gastrectomy at Seoul St. Mary's Hospital between February 2000 and May 2021 were included. We collected 43 peripheral blood samples preoperatively and a pair of gastric mucosal samples postoperatively, including normal and cancer mucosa, which did not influence tumor diagnosis and staging. Tissue microarray samples of GC were collected from 136 patients during surgery. We investigated correlations of immune phenotypes between tissues and peripheral blood using immunofluorescence imaging and flow cytometry, respectively. GC mucosa exhibited an increased number of CD4⁺ T cells, as well as increased expression levels of immunosuppressive markers (e.g., programmed death-ligand-1 [PD-L1], cytotoxic T lymphocyte antigen-4 [CTLA-4], and interleukin-10), in CD4+ T cells and non-T cells.

Result

The expression levels of immunosuppressive markers were significantly increased in cancer tissues and peripheral blood mononuclear cells. In gastric mucosal tissues and peripheral blood of GC patients, similar immunosuppression phenotypes were observed, including increased numbers of PD-L1- and CTLA-4-positive T cells.

Discussion

Therefore, peripheral blood analysis may be an important tool for prognostic assessment of GC patients.

Distinct tumor microenvironment landscapes in gastric cancer classified by cuproptosis-related lncRNAs

Cuproptosis is a newly discovered non-apoptotic form of cell death that may be related to the development of tumors. Nonetheless, the potential role of cuproptosis-related lncRNAs in tumor microenvironment (TME) formation and patient-tailored treatment optimization of gastric cancer (GC) is still unclear. In this study, the six-lncRNA signature was constructed to quantify the molecular patterns of GC using LASSO-Cox regression model. Receiver operating characteristic (ROC) curves, C-index curves, independent prognostic analysis and principal component analysis (PCA) were conducted to verify and evaluate the model. The results showed that this risk model was accurate and reliable in predicting GC patient survival. In addition, two distinct subgroups were identified based on the risk model, which showed significant difference in biological functions of the associated genes, TME scores, characteristics of infiltrating immune cells and immunotherapy responses. We found that the high-risk subgroup was associated with immune activation and tumor-related pathways. Furthermore, compared with the low-risk subgroup, the high-risk subgroup had higher TME scores, richer immune cell infiltration and a better immunotherapy response. To accurately identify immune cold tumors and hot tumors, all samples of GC were divided into four distinct clusters by consensus clustering. Among them, Cluster 3 was identified as an immune hot tumor and was more sensitive to immunotherapy. Overall, this study demonstrates that cuproptosis-related lncRNAs could accurately predict the prognosis of patients with GC, help make a distinction between immune cold tumors and hot tumors and provide a basis for the precision medicine of GC.

Sources of inter-individual variability leading to significant changes in anti-PD-1 and anti-PD-L1 efficacy identified in mouse tumor models using a QSP framework

While anti-PD-1 and anti-PD-L1 [anti-PD-(L)1] monotherapies are effective treatments for many types of cancer, high variability in patient responses is observed in clinical trials. Understanding the sources of response variability can help prospectively identify potential responsive patient populations. Preclinical data may offer insights to this point and, in combination with modeling, may be predictive of sources of variability and their impact on efficacy. Herein, a quantitative systems pharmacology (QSP) model of anti-PD-(L)1 was developed to account for the known pharmacokinetic properties of anti-PD-(L)1 antibodies, their impact on CD8+ T cell activation and influx into the tumor microenvironment, and subsequent anti-tumor effects in CT26 tumor syngeneic mouse model. The QSP model was sufficient to describe the variability inherent in the anti-tumor responses post anti-PD-(L)1 treatments. Local sensitivity analysis identified tumor cell proliferation rate, PD-1 expression on CD8+ T cells, PD-L1 expression on tumor cells, and the binding affinity of PD-1:PD-L1 as strong influencers of tumor growth. It also suggested that treatment-mediated tumor growth inhibition is sensitive to T cell properties including the CD8+ T cell proliferation half-life, CD8+ T cell half-life, cytotoxic T-lymphocyte (CTL)-mediated tumor cell killing rate, and maximum rate of CD8+ T cell influx into the tumor microenvironment. Each of these parameters alone could not predict anti-PD-(L)1 treatment response but they could shift an individual mouse's treatment response when perturbed. The presented preclinical QSP modeling framework provides a path to incorporate potential sources of response variability in human translation modeling of anti-PD-(L)1.