The CCL2-CCR4 Axis Promotes Regulatory T Cell Trafficking to Canine Glioma Tissues.

Purpose: Spontaneously occurring glioma in pet dogs is increasingly recognized as a valuable translational model for human glioblastoma. Canine high grade glioma and human glioblastomas share many molecular similarities, including accumulation of immunosuppressive regulatory T cells (Tregs) that inhibit anti-tumor immune responses. Identifying in dog mechanisms responsible for Treg recruitment may afford targeting the cellular population driving immunosuppression, the results providing a rationale for translational clinical studies in human patients. Our group has previously identified C-C motif chemokine 2 (CCL2) as a glioma-derived T-reg chemoattractant acting on chemokine receptor 4 (CCR4) in a murine orthotopic model of glioma. Recently, we demonstrated a robust increase of CCL2 in the brain tissue of canine patients bearing high-grade glioma. Methods: We performed a series of in vitro experiments using canine Tregs and patient-derived canine glioma cell lines (GSC 1110, GSC 0514, J3T-Bg, G06A) to interrogate the CCL2-CCR4 signaling axis in the canine. Results: We established a flow cytometry gating strategy for identification and isolation of FOXP3+ Tregs in dogs. The canine CD4 + CD25high T-cell population was highly enriched in FOXP3 and CCR4 expression, indicating they are bona fide Tregs. Canine Treg migration was enhanced by CCL2 or by glioma cell line-derived supernatant. Blockade of the CCL2-CCR4 axis significantly reduced migration of canine Tregs. CCL2 mRNA was expressed in all glioma cell lines and expression increased when exposed to Tregs but not to CD4 + helper T-cells. Conclusion: Our study validates CCL2-CCR4 as a bi-directional Treg-glioma immunosuppressive and tumor-promoting axis in canine high-grade glioma.

Tumor-infiltrating T lymphocytes: A promising immunotherapeutic target for preventing immune escape in cholangiocarcinoma.

Cholangiocarcinoma (CCA) is becoming more common and deadly worldwide. Tumor-infiltrating T cell subtypes make distinct contributions to the immune system; collectively, they constitute a significant portion of the tumor microenvironment (TME) in CCA. By secreting cytokines and other chemicals, regulatory T cells (Tregs) decrease activated T cell responses, acting as immunosuppressors. Reduced CD8+ T cell activation results in stimulating programmed death-1 (PD-1), which undermines the immunological homeostasis of T lymphocytes. On the other hand, cancer cells are eliminated by activated cytotoxic T lymphocyte (CTL) through the perforin-granzyme or Fas-FasL pathways. Th1 and CTL immune cell infiltration into the malignant tumor is also facilitated by γδ T cells. A higher prognosis is typically implied by CD8+ T cell infiltration, and survival is inversely associated with Treg cell density. Immune checkpoint inhibitors, either singly or in combination, provide novel therapeutic strategies for CCA immunotherapy. Furthermore, it is anticipated that immunotherapeutic strategies-such as the identification of new immune targets, combination treatments involving several immune checkpoint inhibitors, and chimeric antigen receptor-T therapies (CAR-T)-will optimize the effectiveness of anti-CCA treatments while reducing adverse effects.

Identification and validation of a prognostic model based on four genes related to satellite nodules in hepatocellular carcinoma.

Satellite nodules is a key clinical characteristic which has prognostic value of hepatocellular carcinoma (HCC). Currently, there is no gene-level predictive model for Satellite nodules in liver cancer. For the 377 HCC cases collected from the dataset of Cancer Genome Atlas (TCGA), their original pathological data were analyzed to extract information regarding satellite nodules status as well as other relevant pathological data. Then, this study employed statistical modeling for prognostic model establishment in TCGA, and validation in International Cancer Genome Consortium (ICGC) cohorts and GSE76427. Through rigorous statistical analyses, 253 differential satellite nodules-related genes (SNRGs) were identified, and four key genes related to satellite nodules and prognosis were selected to construct a prognostic model. The high-risk group predicted by our model exhibited an unfavorable overall survival (OS) outlook and demonstrated an association with adverse worse clinical characteristics such as larger tumor size, higher alpha-fetoprotein, microvascular invasion and advanced stage. Moreover, the validation of the model's prognostic value in the ICGC and GSE76427 cohorts mirrored that of the TCGA cohort. Besides, the high-risk group also showed higher levels of resting Dendritic cells, M0 macrophages infiltration, alongside decreased levels of CD8+ T cells and γδT cells infiltration. The prognostic model based on SNRGs can reliability predict the OS of HCC and is likely to have predictive value of immunotherapy for HCC.

Unique immune characteristics and differential anti-PD-1-mediated reinvigoration potential of CD8+ TILs based on BRCA1/2 mutation status in epithelial ovarian cancers.

BACKGROUND: We aimed to investigate the distinct immunological characteristics of the tumor immune microenvironment in epithelial ovarian cancer (EOC) according to BRCA1/2 mutations status and differential PD-1 expression levels. METHODS: Tumor-infiltrating lymphocytes (TILs) were collected from patients with newly diagnosed advanced-stage EOC (YUHS cohort, n=117). This YUHS cohort was compared with The Cancer Genome Atlas (TCGA) data for ovarian serous cystadenocarcinoma (n=482), in terms of survival outcomes and immune-related gene profiles according to BRCA1/2 status. We used multicolor flow cytometry to characterize the immune phenotypes and heterogeneity of TILs with or without BRCA1/2 mutations. In vitro functional assays were conducted to evaluate the reinvigorating ability of CD8+ TILs on anti-PD-1 treatment. RESULTS: We found that EOC patients with BRCA1/2 mutations (BRCA1/2mt) exhibited better survival outcomes and significantly higher tumor mutation burden (TMB), compared with BRCA1/2 non-mutated (BRCA1/2wt) patients. Furthermore, CD8+ TILs within BRCA1/2mt tumors displayed characteristics indicating more severe T-cell exhaustion than their BRCA1/2wt counterparts. Notably, the capacity for anti-PD-1-mediated reinvigoration of CD8+ TILs was significantly greater in BRCA1/2wt tumors compared with BRCA1/2mt tumors. Additionally, within the BRCA1/2wt group, the frequency of PD-1highCD8+ TILs was positively correlated with the reinvigoration capacity of CD8+ TILs after anti-PD-1 treatment. CONCLUSION: Our results highlight unique immune features of CD8+ TILs in EOC and a differential response to anti-PD-1 treatment, contingent on BRCA1/2 mutation status. These findings suggest that immune checkpoint blockade may be a promising frontline therapeutic option for selected BRCA1/2wt EOC patients.

Hypoxia inhibits the iMo/cDC2/CD8+ TRMs immune axis in the tumor microenvironment of human esophageal cancer.

BACKGROUND: Esophageal cancer (ESCA) is a form of malignant tumor associated with chronic inflammation and immune dysregulation. However, the specific immune status and key mechanisms of immune regulation in this disease require further exploration. METHODS: To investigate the features of the human ESCA tumor immune microenvironment and its possible regulation, we performed mass cytometry by time of flight, single-cell RNA sequencing, multicolor fluorescence staining of tissue, and flow cytometry analyses on tumor and paracancerous tissue from treatment-naïve patients. RESULTS: We depicted the immune landscape of the ESCA and revealed that CD8+ (tissue-resident memory CD8+ T cells (CD8+ TRMs) were closely related to disease progression. We also revealed the heterogeneity of CD8+ TRMs in the ESCA tumor microenvironment (TME), which was associated with their differentiation and function. Moreover, the subset of CD8+ TRMs in tumor (called tTRMs) that expressed high levels of granzyme B and immune checkpoints was markedly decreased in the TME of advanced ESCA. We showed that tTRMs are tumor effector cells preactivated in the TME. We then demonstrated that conventional dendritic cells (cDC2s) derived from intermediate monocytes (iMos) are essential for maintaining the proliferation of CD8+ TRMs in the TME. Our preliminary study showed that hypoxia can promote the apoptosis of iMos and impede the maturation of cDC2s, which in turn reduces the proliferative capacity of CD8+ TRMs, thereby contributing to the progression of cancer. CONCLUSIONS: Our study revealed the essential antitumor roles of CD8+ TRMs and preliminarily explored the regulation of the iMo/cDC2/CD8+ TRM immune axis in the human ESCA TME.

Use of Tumor-Infiltrating Lymphocyte (TIL) Cell Therapy For Spindle Cell Carcinoma of the Breast: A Case Report.

BACKGROUND: Spindle cell carcinoma (SCC) of the breast is a rare type of metaplastic carcinoma with poor prognosis, high recurrence, and distant metastasis. Mammectomy, chemotherapy, radiotherapy, and endocrine therapy are the preferred choices of treatments. Tumor-infiltrating lymphocyte (TIL) therapy, which utilizes the patient's immune cells from the solid tumor micro-environment to eradicate cancer cells, has shown promising results in treating advanced solid tumors. However, its use for SCC of the breast has not been reported. CASE PRESENTATION: Here, we present a case of combining TIL therapy with personalized chemotherapy and endocrine therapy for the treatment of SCC of the breast. A 36-year-old Chinese woman presented with a palpable nodule (32 mm) on her left breast. Based on histological and immunohistochemical analysis of breast biopsy and surgical specimens, she was diagnosed with SCC of the breast (stage IIA). The patient received concurrent personalized chemotherapy, TIL therapy, and endocrine therapy following mammectomy. She showed no severe side effects during therapy, and did not present local recurrence or distant metastasis after follow-up for at least 14 months. CONCLUSION: To our knowledge, this is the first case report, which demonstrated that TIL therapy combined with chemotherapy/endocrine therapy after mastectomy is safe and effective for SCC of the breast.

Identification and validation of tumor-specific T cell receptors from tumor infiltrating lymphocytes using tumor organoid co-cultures.

T cell receptor-engineered T cells (TCR-Ts) therapy is promising for cancer immunotherapy. Most studies have focused on identifying tumor-specific T cell receptors (TCRs) through predicted tumor neoantigens. However, current algorithms for predicting tumor neoantigens are unreliable and many neoantigens are derived from non-coding regions. Thus, the technological platform for identifying tumor-specific TCRs using natural antigens expressed on tumor cells is urgently needed. In this study, tumor organoids-enriched tumor infiltrating lymphocytes (oeT) were obtained by repeatedly stimulation of autologous patient-derived organoids (PDO) in vitro. The oeT cells specifically responded to autologous tumor PDO by detecting CD137 expression and the secretion of IFN-γ using enzyme-linked immunospot assay. The measurement of oeT cell-mediated killing of three-dimensional organoids was conducted using a caspase3/7 flow cytometry assay kit. Subsequently, tumor-specific T cells were isolated based on CD137 expression and their TCRs were identified through single-cell RT-PCR analysis. The specificity cytotoxicity of TCRs were confirmed by transferring to primary peripheral blood T cells. The co-culture system proved highly effective in generating CD8+ tumor-specific oeT cells. These oeT cells effectively induced IFN-γ secretion and exhibited specificity in killing autologous tumor organoids, while not eliciting a cytotoxic response against normal organoids. The analysis conducted by TCRs revealed a significant expansion of T cells within a specific subset of TCRs. Subsequently, the TCRs were cloned and transferred to peripheral blood T cells generation engineered TCR-Ts, which adequately recognized and killed tumor cell in a patient-specific manner. The co-culture system provided an approach to generate tumor-specific TCRs from tumor-infiltrating lymphocytes of patients with colorectal cancer, and tumor-specific TCRs can potentially be used for personalized TCR-T therapy.

Second-generation checkpoint inhibitors and Treg depletion synergize with a mouse cancer vaccine in accordance with tumor microenvironment characterization.

BACKGROUND: Despite advances in checkpoint inhibitor (CPI) therapy for cancer treatment, many cancers remain resistant. Tumors deemed "cold" based on lack of T cell infiltration show reduced potential for CPI therapy. Cancer vaccines may overcome the inadequacy of existing T cells by inducing the needed antitumor T cell response to synergize with CPIs and overcome resistance. METHODS: CT26 and TC1 tumor cells were injected subcutaneously into mice. Mice were treated with combinations of CPIs alone or a cancer vaccine specific to the tumor antigen E7 present in TC1 cells. CPIs for the TC1 model were selected because of immunophenotyping TC1 tumors. Antitumor and protumor immunity, tumor size and survival, sequence and timing of vaccine and CPI administration, and efficacy of treatment in young and aged mice were probed. RESULTS: While "hot" CT26 tumors are treatable with combinations of second-generation CPIs alone or with anti-TGFß, "cold" TC1 tumor reduction requires the synergy of a tumor-antigen-specific vaccine in combination with two CPIs, anti-TIGIT and anti-PD-L1, predicted by tumor microenvironment (TME) characterization. The synergistic triple combination delays tumor growth better than any pairwise combination and improves survival in a CD8+T cell-dependent manner. Depletion of CD4+T cells improved the treatment response, and depleting regulatory T cells (Treg) revealed Tregs to be inhibiting the response as also predicted from TME analysis. We found the sequence of CPI and vaccine administration dictates the success of the treatment, and the triple combination administered concurrently induces the highest E7-specific T cell response. Contrary to young mice, in aged mice, the cancer vaccine alone is ineffective, requiring the CPIs to delay tumor growth. CONCLUSIONS: These findings show how pre-existing or vaccine-mediated de novo T cell responses can both be amplified by and facilitate synergistic CPIs and Treg depletion that together lead to greater survival, and how analysis of the TME can help rationally design combination therapies and precision medicine to enhance clinical response to CPI and cancer vaccine therapy.

Baseline tumor-infiltrating lymphocyte patterns and response to immune checkpoint inhibition in metastatic cutaneous melanoma.

INTRODUCTION: The presence of tumor-infiltrating lymphocytes (TILs) in melanoma has been linked to survival. Their predictive capability for immune checkpoint inhibition (ICI) response remains uncertain. Therefore, we investigated the association between treatment response and TILs in the largest cohort to date and analyzed if this association was independent of known clinical predictors. METHODS: In this multicenter cohort study, patients who received first-line anti-PD1 ± anti-CTLA4 for advanced melanoma were identified. TILs were scored on hematoxylin and eosin (H&E) slides of primary melanoma and pre-treatment metastases using the validated TILs-WG, Clark and MIA score. The primary outcome was objective response rate (ORR), with progression free survival and overall survival being secondary outcomes. Univariable and multivariable logistic regression and Cox proportional hazard were performed, adjusting for known clinical predictors. RESULTS: Metastatic melanoma specimens were available for 650 patients and primary specimens for 565 patients. No association was found in primary melanoma specimens. In metastatic specimens, a 10-point increase in the TILs-WG score was associated with a higher probability of response (aOR 1.17, 95 % CI 1.07-1.28), increased PFS (HR 0.93, 95 % CI 0.87-0.996), and OS (HR 0.94, 95 % CI 0.89-0.99). When categorized, patients in the highest tertile TILs-WG score (15-100 %) compared to the lowest tertile (0 %) had a longer median PFS (13.1 vs. 7.3 months, p = 0.04) and OS (49.4 vs. 19.5 months, p = 0.003). Similar results were noted using the MIA and Clark scores. CONCLUSION: In advanced melanoma patients, TIL patterns on H&E slides of pre-treatment metastases, regardless of measurement method, are independently associated with ICI response. TILs are easily scored on readily available H&Es, facilitating the use of this biomarker in clinical practice.

Deep learning-based and BI-RADS guided radiomics model for automatic tumor-infiltrating lymphocytes evaluation in breast cancer.

OBJECTIVES: To investigate an interpretable radiomics model consistent with clinical decision-making process and realize automatic prediction of tumor-infiltrating lymphocytes (TILs) levels in breast cancer (BC) from ultrasound (US) images. METHODS: A total of 378 patients with invasive BC confirmed by pathological results were retrospectively enrolled in this study. Radiomics features were extracted guided by the BI-RADS lexicon from the regions of interest(ROIs) segmented with deep learning models. After features selected using the least absolute shrinkage and selection operator(LASSO) regression, four machine learning classifiers were used to establish the radiomics signature(Rad-score). Then, the integrated model was developed on the basis of the best Rad-score incorporating the independent clinical factors for TILs levels prediction. RESULTS: Tumors were segmented using the deep learning models with accuracy of 97.2%, sensitivity of 93.4%, specificity of 98.1%, and the posterior areas were also obtained. Eighteen morphology and texture related features were extracted from the ROIs and fourteen features were selected to construct the Rad-score models. Combined with independent clinical characteristics, the integrated model achieved an area under the curve (AUC) of 0.889(95% CI,0.739,0.990) in the validation cohort and outperformed the traditional radiomics model with AUC of 0.756(0.649-0862) depended on hundreds of feature items. CONCLUSIONS: This study established a promising model for TILs levels prediction with numerable interpretable features and showed great potential to help decision-making and clinical applications. ADVANCES IN KNOWLEDGE: Imaging-based biomarkers has provides non-invasive ways for TILs levels evaluation in BC. Our model combining the BI-RADS guided radiomics features and clinical data outperformed the traditional radiomics approaches.

Toxoplasma gondii infection supports the infiltration of T cells into brain tumors.

Few T cells infiltrate into primary brain tumors, fundamentally hampering the effectiveness of immunotherapy. We hypothesized that Toxoplasma gondii, a microorganism that naturally elicits a Th1 response in the brain, can promote T cell infiltration into brain tumors despite their immune suppressive microenvironment. Using a mouse genetic model for medulloblastoma, we found that T. gondii infection induced the infiltration of activatable T cells into the tumor mass and led to myeloid cell reprogramming toward a T cell-supportive state, without causing severe health issues in mice. The study provides a concrete foundation for future studies to take advantage of the immune modulatory capacity of T. gondii to facilitate brain tumor immunotherapy.

Transforming pancreaticobiliary cancer treatment: Exploring the frontiers of adoptive cell therapy and cancer vaccines.

Pancreaticobiliary cancer, encompassing malignancies of both the pancreatic and biliary tract, presents a formidable clinical challenge marked by a uniformly bleak prognosis. The asymptomatic nature of its early stages often leads to delayed detection, contributing to an unfavorable 5-year overall survival rate. Conventional treatment modalities have shown limited efficacy, underscoring the urgent need for alternative therapeutic approaches. In recent years, immunotherapy has emerged as a promising avenue in the fight against pancreaticobiliary cancer. Strategies such as therapeutic vaccines and the use of tumor-infiltrating lymphocytes have garnered attention for their potential to elicit more robust and durable responses. This review seeks to illuminate the landscape of emerging immunotherapeutic interventions, offering insights from both clinical and research perspectives. By deepening our understanding of pancreaticobiliary cancer and exploring innovative treatment modalities, we aim to catalyze improvements in patient outcomes and quality of life.

Training immunophenotyping deep learning models with the same-section ground truth cell label derivation method improves virtual staining accuracy.

Introduction: Deep learning (DL) models predicting biomarker expression in images of hematoxylin and eosin (H&E)-stained tissues can improve access to multi-marker immunophenotyping, crucial for therapeutic monitoring, biomarker discovery, and personalized treatment development. Conventionally, these models are trained on ground truth cell labels derived from IHC-stained tissue sections adjacent to H&E-stained ones, which might be less accurate than labels from the same section. Although many such DL models have been developed, the impact of ground truth cell label derivation methods on their performance has not been studied. Methodology: In this study, we assess the impact of cell label derivation on H&E model performance, with CD3+ T-cells in lung cancer tissues as a proof-of-concept. We compare two Pix2Pix generative adversarial network (P2P-GAN)-based virtual staining models: one trained with cell labels obtained from the same tissue section as the H&E-stained section (the 'same-section' model) and one trained on cell labels from an adjacent tissue section (the 'serial-section' model). Results: We show that the same-section model exhibited significantly improved prediction performance compared to the 'serial-section' model. Furthermore, the same-section model outperformed the serial-section model in stratifying lung cancer patients within a public lung cancer cohort based on survival outcomes, demonstrating its potential clinical utility. Discussion: Collectively, our findings suggest that employing ground truth cell labels obtained through the same-section approach boosts immunophenotyping DL solutions.

New Emerging Chemokine Receptors: CCR5 or CXCR5 on Tumor Is Associated with Poor Response to Chemotherapy and Poor Prognosis in Locally Advanced Triple-Negative Breast Cancer.

BACKGROUND: We aim to investigate any possible associations between chemokine receptor expression and responses to neoadjuvant chemotherapy (NAC) along with outcomes in patients with triple-negative breast cancer (TNBC) with locally advanced disease. METHOD: Expressions of chemokine receptors were examined immunohistochemically after staining archival tissue of surgical specimens (n = 63) using specific antibodies for CCR5, CCR7, CXCR4, and CXCR5. RESULTS: Patients with high CCR5, CCR7, CXCR4, and CXCR5 expression on tumors and high CXCR4 expression on tumor-infiltrating lymphocytes (TILs) were less likely to have a pathological complete response (pCR) or Class 0-I RCB-Index compared to others. Patients with residual lymph node metastases (ypN-positive), high CCR5TM(tumor), and high CXCR4TM expressions had an increased hazard ratio (HR) compared to others (DFS: HR = 2.655 [1.029-6.852]; DSS: HR = 2.763 [1.008-7.574]), (DFS: HR = 2.036 [0.805-5.148]; DSS: HR = 2.689 [1.020-7.090]), and (DFS: HR = 2.908 [1.080-7.829]; DSS: HR = 2.132 (0.778-5.846)), respectively. However, patients without CXCR5TIL expression had an increased HR compared to those with CXCR5TIL (DFS: 2.838 [1.266-6.362]; DSS: 4.211 [1.770-10.016]). CONCLUSIONS: High expression of CXCR4TM and CCR5TM was found to be associated with poor prognosis, and CXCR5TM was associated with poor chemotherapy response in the present cohort with locally advanced TNBC. Our results suggest that patients with TNBC could benefit from a chemokine receptor inhibitor therapy containing neoadjuvant chemotherapy protocols.

Spatial colocalization and combined survival benefit of natural killer and CD8 T cells despite profound MHC class I loss in non-small cell lung cancer.

Background: MHC class I (MHC-I) loss is frequent in non-small cell lung cancer (NSCLC) rendering tumor cells resistant to T cell lysis. NK cells kill MHC-I-deficient tumor cells, and although previous work indicated their presence at NSCLC margins, they were functionally impaired. Within, we evaluated whether NK cell and CD8 T cell infiltration and activation vary with MHC-I expression. Methods: We used single-stain immunohistochemistry (IHC) and Kaplan-Meier analysis to test the effect of NK cell and CD8 T cell infiltration on overall and disease-free survival. To delineate immune covariates of MHC-I-disparate lung cancers, we used multiplexed immunofluorescence (mIF) imaging followed by multivariate statistical modeling. To identify differences in infiltration and intercellular communication between IFNγ-activated and non-activated lymphocytes, we developed a computational pipeline to enumerate single cell neighborhoods from mIF images followed by multivariate discriminant analysis. Results: Spatial quantitation of tumor cell MHC-I expression revealed intra- and inter-tumoral heterogeneity, which was associated with the local lymphocyte landscape. IHC analysis revealed that high CD56+ cell numbers in patient tumors were positively associated with disease-free survival (DFS) (HR=0.58, p=0.064) and overall survival (OS) (HR=0.496, p=0.041). The OS association strengthened with high counts of both CD56+ and CD8+ cells (HR=0.199, p<1×10-3). mIF imaging and multivariate discriminant analysis revealed enrichment of both CD3+CD8+ T cells and CD3-CD56+ NK cells in MHC-I-bearing tumors (p<0.05). To infer associations of functional cell states and local cell-cell communication, we analyzed spatial single cell neighborhood profiles to delineate the cellular environments of IFNγ+/- NK cells and T cells. We discovered that both IFNγ+ NK and CD8 T cells were more frequently associated with other IFNγ+ lymphocytes in comparison to IFNγ- NK cells and CD8 T cells (p<1×10-30). Moreover, IFNγ+ lymphocytes were most often found clustered near MHC-I+ tumor cells. Conclusions: Tumor-infiltrating NK cells and CD8 T cells jointly affected control of NSCLC tumor progression. Co-association of NK and CD8 T cells was most evident in MHC-I-bearing tumors, especially in the presence of IFNγ. Frequent co-localization of IFNγ+ NK cells with other IFNγ+ lymphocytes in near-neighbor analysis suggests NSCLC lymphocyte activation is coordinately regulated.

The CCL2-CCR4 axis promotes Regulatory T cell trafficking to canine glioma tissues.

PURPOSE: Spontaneously occurring glioma in pet dogs is increasingly recognized as a valuable translational model for human glioblastoma. Canine high-grade glioma and human glioblastomas share many molecular similarities, including the accumulation of immunosuppressive regulatory T cells (Tregs) that inhibit anti-tumor immune responses. Identifying in dog mechanisms responsible for Treg recruitment may afford to target the cellular population driving immunosuppression, the results providing a rationale for translational clinical studies in human patients. Our group has previously identified C-C motif chemokine 2 (CCL2) as a glioma-derived T-reg chemoattractant acting on chemokine receptor 4 (CCR4) in a murine orthotopic glioma model. Recently, we demonstrated a robust increase of CCL2 in the brain tissue of canine patients bearing high-grade glioma. METHODS: We performed a series of in vitro experiments using canine Tregs and patient-derived canine glioma cell lines (GSC 1110, GSC 0514, J3T-Bg, G06A) to interrogate the CCL2-CCR4 signaling axis in the canine. RESULTS: We established a flow cytometry gating strategy for identifying and isolating FOXP3+ Tregs in dogs. The canine CD4 + CD25high T-cell population was highly enriched in FOXP3 and CCR4 expression, indicating they are bona fide Tregs. Canine Treg migration was enhanced by CCL2 or by glioma cell line-derived supernatant. Blockade of the CCL2-CCR4 axis significantly reduced migration of canine Tregs. CCL2 mRNA was expressed in all glioma cell lines, and expression increased when exposed to Tregs but not CD4 + helper T-cells. CONCLUSION: Our study validates CCL2-CCR4 as a bi-directional Treg-glioma immunosuppressive and tumor-promoting axis in canine high-grade glioma.

The impact of the tumor immune microenvironment and tumor-infiltrating lymphocyte subgroups on laryngeal cancer prognosis.

The absence of improvement in survival rates across various cancers, including laryngeal cancer, has led to an increasing interest in understanding the immune response to cancer. In head and neck cancers, immune modulatory mechanisms such as immune microenvironment and immune infiltration are important in cancer pathogenesis. This study aims to explore the distribution of tumor-infiltrating lymphocyte (TIL) subgroups in the immune microenvironment and evaluate their impact on tumor histopathological characteristics and prognosis. The study included 50 patients who underwent laryngectomy for laryngeal squamous cell carcinoma, in Istanbul University - Cerrahpasa, Faculty of Medicine Department of Otorhinolaryngology, between January 2016 and January 2018. Pathology specimens were evaluated using immunohistochemistry to assess the expressions of the CD3, CD20, CD8, CD4, CD25, and FoxP3 markers, identifying subgroups of TILs. The investigation aimed to uncover how these subgroups influence tumor histopathological features and survival outcomes. The high infiltration of CD3, CD20, and CD4 had a positive impact on disease-specific survival, disease-free survival, and recurrence-free survival. In addition, overall survival was positively affected by high CD3 and CD4 infiltrations. However, no significant relationship was observed between the expressions of CD8, FoxP3, and CD25 and any of the survival parameters. The infiltration of CD3, CD20, and CD4 positive cells indicative of a robust antitumoral immune response-emerged as favorable prognostic factors in laryngeal cancer. These findings suggest that enhancing the infiltration of CD3, CD20, and CD4 lymphocytes could be a therapeutic strategy worth exploring in clinical trials.

Characteristics of auto-quantified tumor-infiltrating lymphocytes and the prognostic value in adenocarcinoma of the esophagogastric junction, gastric adenocarcinoma, and esophageal squamous cell carcinoma.

BACKGROUND: Adenocarcinoma of the esophagogastric junction (AEGJ) with a specific pathological profile and poor prognosis has limited therapeutic options. Previous studies have found that TILs exhibit distinct characteristics in different tumors and are correlated with tumor prognosis. We established cellular training sets to obtain auto-quantified TILs in pathological images. And we compared the characteristics of TILs in AEGJ with those in esophageal squamous cell carcinoma (ESCC) and gastric adenocarcinoma (GAC) to gain insight into the unique immune environments of these three tumors and investigate the prognostic value of TILs in these three tumors. METHODS: Utilizing a case-control study design, we analyzed 214 AEGJ, 256 GAC, and 752 ESCC cases. The TCGA dataset was used to validate prognostic value of auto-quantified TILs. The specific cellular training sets were established by experienced pathologists to determine TILs counts. Kruskal-Wallis test and multi-variable linear regression were conducted to explore TILs characteristics. Survival analyses were performed with Kaplan-Meier method and Cox proportional hazards model. RESULTS: The three cellular training sets of these cancers achieved a classification accuracy of 87.55 at least. The median auto-quantified TILs of AEGJ, GAC, and ESCC cases were 4.82%, 1.92%, and 0.12%, respectively. The TILs demonstrated varied characteristics under distinctive clinicopathological traits. The higher TILs proportion was associated with better prognosis in esophagogastric cancers (all P < 0.05) and was an independent prognostic biomarker on AEGJ in both datasets (Taixing: HR = 0.965, 95% CI = 0.938-0.994; TCGA: HR = 0.811, 95% CI = 0.712-0.925). CONCLUSIONS: We found variations in TILs across ESCC, GAC, and AEGJ, as assessed by image processing algorithms. Additionally, TILs in these three cancers are an independent prognostic factor. This enhances our understanding of the unique immune characteristics of the three tumors, improving patient outcomes.

Dense tumor-infiltrating lymphocytes (TILs) in liver metastasis from colorectal cancer are related to improved overall survival.

BACKGROUND AND OBJECTIVES: Tumor-infiltrating lymphocytes (TILs) represent a host-tumor interaction, frequently signifying an augmented immunological response. Nonetheless, implications with survival outcomes in patients with colorectal carcinoma liver metastasis (CRLM) warrant rigorous validation. The objective was to demonstrate the association between TILs and survival in patients with CRLM. METHOD: In a retrospective evaluation conducted in a single institution, we assessed all patients who underwent hepatectomy due to CRLM between 2014 and 2018. Comprehensive medical documentation reviews were executed. TILs were assessed by a liver pathologist, blinded to the clinical information, in all surgical slides. RESULTS: This retrospective cohort included 112 patients. Median overall survival (OS) was 58 months and disease-free survival (DFS) was 12 months for the entire cohort. Comparison between groups showed a median OS of 81 months in the dense TILs group and 40 months in the weak/absent group (p = 0.001), and DFS was 14 months versus 9 months (p = 0.041). Multivariable analysis showed that TILs were an independent predictor of OS (HR 1.95; p = 0.031). CONCLUSIONS: Dense TILs are a pivotal prognostic indicator, correlating with enhanced OS. Including TILs information in histopathological evaluations should refine the clinical decision-making process for this group of patients.

Clinical and translational implications of immunotherapy in sarcomas.

Immunotherapy has emerged as promising treatment in sarcomas, but the high variability in terms of histology, clinical behavior and response to treatments determines a particular challenge for its role in these neoplasms. Tumor immune microenvironment (TiME) of sarcomas reflects the heterogeneity of these tumors originating from mesenchymal cells and encompassing more than 100 histologies. Advances in the understanding of the complexity of TiME have led to an improvement of the immunotherapeutic responsiveness in sarcomas, that at first showed disappointing results. The proposed immune-classification of sarcomas based on the interaction between immune cell populations and tumor cells showed to have a prognostic and potential predictive role for immunotherapies. Several studies have explored the clinical impact of immune therapies in the management of these histotypes leading to controversial results. The presence of Tumor Infiltrating Lymphocytes (TIL) seems to correlate with an improvement in the survival of patients and with a higher responsiveness to immunotherapy. In this context, it is important to consider that also immune-related genes (IRGs) have been demonstrated to have a key role in tumorigenesis and in the building of tumor immune microenvironment. The IRGs landscape in soft tissue and bone sarcomas is characterized by the connection between several tumor-related genes that can assume a potential prognostic and predictive therapeutic role. In this paper, we reviewed the state of art of the principal immune strategies in the management of sarcomas including their clinical and translational relevance.