The prognostic value of intratumoral and peritumoral tumor-infiltrating FoxP3+Treg cells in of pancreatic adenocarcinoma: a meta-analysis

CD3-CD8 immune score associated with a clinical score stratifies PDAC prognosis regardless of adjuvant or neoadjuvant chemotherapy

Stratification of the prognosis of pancreatic cancer (PDAC) patients treated by surgery is based solely on clinical variables, such as tumor stage and node status. The development of biomarkers of relapse is needed, especially to drive administration of adjuvant therapy in this at-risk population. Our study evaluates the prognostic performance of a CD3- and CD8-based immune score. CD3, CD8 and Foxp3 expression were evaluated on whole slides in two retrospective PDAC cohorts totaling 334 patients. For this study, we developed an immune score to estimate CD3 and CD8 infiltration in both tumor core and invasive margin using computer-guided analysis with QuPath software. Variables were combined in a dichotomous immune score. The association between immune and clinical scores, and both PFS and OS was investigated. We observed that a dichotomous immune score predicts both PFS and OS of localized PDAC. By univariate and multivariate analysis, immune score, tumor grade, adjuvant therapy, lymph node status, and adjuvant chemotherapy administration were associated with PFS and OS. We subsequently associated the PDAC immune score and clinical variables in a combined score. This combined score predicted patient outcomes independently of adjuvant or neoadjuvant treatment, and improved patient prognostic prediction compared to clinical variables or immune score alone.

Tertiary lymphoid structures in pancreatic cancer: a new target for immunotherapy

Pancreatic cancer (PC) is extremely malignant and shows limited response to available immunotherapies due to the hypoxic and immunosuppressive nature of its tumor microenvironment (TME). The aggregation of immune cells (B cells, T cells, dendritic cells, etc.), which is induced in various chronic inflammatory settings such as infection, inflammation, and tumors, is known as the tertiary lymphoid structure (TLS). Several studies have shown that TLSs can be found in both intra- and peritumor tissues of PC. The role of TLSs in peritumor tissues in tumors remains unclear, though intratumoral TLSs are known to play an active role in a variety of tumors, including PC. The formation of intratumoral TLSs in PC is associated with a good prognosis. In addition, TLSs can be used as an indicator to assess the effectiveness of treatment. Targeted induction of TLS formation may become a new avenue of immunotherapy for PC. This review summarizes the formation, characteristics, relevant clinical outcomes, and clinical applications of TLSs in the pancreatic TME. We aim to provide new ideas for future immunotherapy of PC.

Distribution characteristics and clinical significance of infiltrating T cells in the tumor microenvironment of pancreatic cancer

Tumor-infiltrating lymphocytes (TILs) are important components of the tumor microenvironment (TME). However, the distribution characteristics of TILs and their significance in pancreatic cancer (PC) remain largely unexplored. The levels of TILs, including the total number of T cells, cluster of differentiation (CD)4⁺ T cells, CD8⁺ cytotoxic T lymphocytes (CTLs), regulatory T-cells (Tregs), programmed cell death protein 1⁺ T cells and programmed cell death ligand 1 (PD-L1)⁺ T cells, in the TME of patients with PC were detected using multiple fluorescence immunohistochemistry. The associations between the number of TILs and the clinicopathological characteristics were investigated using χ² tests. In addition, Kaplan-Meier survival and Cox regression analyses were used to assess the prognostic value of these TIL types. Compared with paracancerous tissues, in PC tissues, the proportions of total T cells, CD4⁺ T cells and CD8⁺ CTLs were markedly decreased, while those of Tregs and PD-L1⁺ T cells were significantly increased. The levels of CD4⁺ T cell and CD8⁺ CTL infiltrates were inversely associated with tumor differentiation. Higher infiltrates of Tregs and PD-L1⁺ T cells were closely associated with advanced N and TNM stages. It is important to note that the infiltrates of total T cells, CD4⁺ T cells, Tregs and PD-L1⁺ T cells in the TME were independent risk factors for the prognosis of PC. PC was characterized by an immunosuppressive TME with a decrease in the number of CD4⁺ T cells and CD8⁺ CTLs, and an increase in the number of Tregs and PD-L1⁺ T cells. Overall, the number of total T cells, CD4⁺ T cells, Tregs and PD-L1⁺ T cells in the TME was a potential predictive marker for the prognosis of PC.

Addition of Losartan to FOLFIRINOX and Chemoradiation Reduces Immunosuppression-Associated Genes, Tregs, and FOXP3+ Cancer Cells in Locally Advanced Pancreatic Cancer

PURPOSE

Adding losartan (LOS) to FOLFIRINOX (FFX) chemotherapy followed by chemoradiation (CRT) resulted in 61% R0 surgical resection in our phase II trial in patients with locally advanced pancreatic cancer (LAPC). Here we identify potential mechanisms of benefit by assessing the effects of neoadjuvant LOS on the tumor microenvironment.

EXPERIMENTAL DESIGN

We performed a gene expression and immunofluorescence (IF) analysis using archived surgical samples from patients treated with LOS+FFX+CRT (NCT01821729), FFX+CRT (NCT01591733), or surgery upfront, without any neoadjuvant therapy. We also conducted a longitudinal analysis of multiple biomarkers in the plasma of treated patients.

RESULTS

In comparison with FFX+CRT, LOS+FFX+CRT downregulated immunosuppression and pro-invasion genes. Overall survival (OS) was associated with dendritic cell (DC) and antigen presentation genes for patients treated with FFX+CRT, and with immunosuppression and invasion genes or DC- and blood vessel-related genes for those treated with LOS+FFX+CRT. Furthermore, LOS induced specific changes in circulating levels of IL-8, sTie2, and TGF-β. IF revealed significantly less residual disease in lesions treated with LOS+FFX+CRT. Finally, patients with a complete/near complete pathologic response in the LOS+FFX+CRT-treated group had reduced CD4+FOXP3+ regulatory T cells (Tregs), fewer immunosuppressive FOXP3+ cancer cells (C-FOXP3), and increased CD8+ T cells in pancreatic ductal adenocarcinoma lesions.

CONCLUSIONS

Adding LOS to FFX+CRT reduced pro-invasion and immunosuppression-related genes, which were associated with improved OS in patients with LAPC. Lesions from responders in the LOS+FFX+CRT-treated group had reduced Tregs, decreased C-FOXP3 and increased CD8+ T cells. These findings suggest that LOS may potentiate the benefit of FFX+CRT by reducing immunosuppression.

A multigene circulating biomarker to predict the lack of FOLFIRINOX response after a single cycle in patients with pancreatic ductal adenocarcinoma

INTRODUCTION

5-fluorouracil, folinic acid, irinotecan and oxaliplatin (FOLFIRINOX) is promising in treating patients with pancreatic ductal adenocarcinoma. However, many patients and physicians are reluctant to start FOLFIRINOX due to its high toxicity and limited clinical response rates. In this study, we investigated the effect of a single FOLFIRINOX cycle, in combination with a granulocyte colony-stimulating factor, on the blood immune transcriptome of patients with pancreatic ductal adenocarcinoma. We aimed to identify an early circulating biomarker to predict the lack of FOLFIRINOX response.

METHODS

Blood samples of 68 patients from all disease stages, who received at least four FOLFIRINOX cycles, were collected at baseline and after the first cycle. The response to treatment was radiologically evaluated following the Response Evaluation Criteria in Solid Tumours criteria 1.1. Targeted immune-gene expression profiling (GEP) was performed using NanoString technologies. To predict the lack of FOLFIRINOX response, we developed a FOLFIRINOX delta GEP (FFX-ΔGEP) score.

RESULTS

A single FOLFIRINOX cycle significantly altered 395 genes, correlating to 30 significant alterations in relative immune cell abundances and pathway activities. The eight-gene (BID, FOXP3, KIR3DL1, MAF, PDGFRB, RRAD, SIGLEC1 and TGFB2) FFX-ΔGEP score predicted the lack of FOLFIRINOX response with a leave-one-out cross-validated area under the curve (95% confidence interval) of 0.87 (0.60-0.98), thereby outperforming the predictiveness of absolute and proportional Δcarbohydrate antigen19-9 values.

CONCLUSIONS

A single FOLFIRINOX cycle, combined with granulocyte colony-stimulating factor, alters the peripheral immune transcriptome indisputably. Our novel FFX-ΔGEP is, to our knowledge, the first multigene early circulating biomarker that predicts the lack of FOLFIRINOX response after one cycle. Validation in a larger independent patient cohort is crucial before clinical implementation.

Regulatory T Cells but Not Tumour-Infiltrating Lymphocytes Correlate with Tumour Invasion Depth in Basal Cell Carcinoma

Basal cell carcinoma (BCC) is the most common skin malignancy worldwide. Current evidence suggests tumour-infiltrating lymphocytes (TILs) may influence the clinical outcomes of patients with BCC. The present study aimed to profile the infiltrative characteristics of stromal TILs and regulatory T cells (Treg cells) in the tumour centre (TC), tumour periphery (TP), and normal adjacent tissue (NAT) of BCC. A total of 111 samples from 43 cutaneous BCC cases were examined for TIL (CD3+) and Treg cell (FOXP3+/CD3+) expression using immunohistochemical techniques. The correlations of Treg cells with TILs, invasion depth, and tumour morphological risk were analysed. We identified a high mean proportion of Treg cells within the tumour (TC = 46.9%, TP = 56.1%, NAT = 51.8%) despite a relatively low median of TILs (TC = 12.7%, TP = 10.3%, NAT = 3.6%), supporting the classification of BCC as a cold tumour. A significant positive correlation was observed between the proportion of Treg cells and sTILs (ρ = 0.325, p < 0.001), suggesting a predominant role of TILs in the infiltration of Treg cells. An inverse correlation discovered between Treg cells and tumour invasion depth (r = −0.36, p = 0.017) might indicate Treg cells’ anti-tumour capacity in BCC.

Immunoregulatory signal networks and tumor immune evasion mechanisms: insights into therapeutic targets and agents in clinical development

Through activation of immune cells, the immune system is responsible for identifying and destroying infected or otherwise damaged cells including tumorigenic cells that can be recognized as foreign, thus maintaining homeostasis. However, tumor cells have evolved several mechanisms to avoid immune cell detection and killing, resulting in tumor growth and progression. In the tumor microenvironment, tumor infiltrating immune cells are inactivated by soluble factors or tumor promoting conditions and lose their effects on tumor cells. Analysis of signaling and crosstalk between immune cells and tumor cells have helped us to understand in more detail the mechanisms of tumor immune evasion and this forms basis for drug development strategies in the area of cancer immunotherapy. In this review, we will summarize the dominant signaling networks involved in immune escape and describe the status of development of therapeutic strategies to target tumor immune evasion mechanisms with focus on how the tumor microenvironment interacts with T cells.

Extracellular vesicles in pancreatic cancer immune escape: Emerging roles and mechanisms

Pancreatic cancer (PC) is the most lethal malignancy worldwide due to its delayed diagnosis and limited treatment options. Despite great progress in clinical trials of immunotherapies for various cancers, their effectiveness in PC is very low, indicating that immune evasion is still a major obstacle to immunotherapy in PC. However, the mechanism of immune escape in PC is not fully understood, which substantially restricts the development of immunotherapy. As an important component of intercellular communication networks, extracellular vesicles (EVs) have attracted increasing attention in relation to immune escape. This review aims to provide a better understanding of the roles of EVs in tumor immune escape and the potential to expand their application in cancer immunotherapy. The relationship between PC and the tumor immune microenvironment is briefly introduced. Then, the mechanism by which EVs are involved in immune regulation is summarized, and the latest progress in determining the role of EVs in regulating PC immune escape is highlighted.

On the Prognostic Power of Tumor-Infiltrating Lymphocytes – A Critical Commentary

Tumor-infiltrating lymphocytes are extensively used as prognostic biomarkers in cancer. Regulatory T cells (Tregs) or CD8+ T cells frequencies in tumor site, or their ratio, are the most common markers used to assess prognosis. This work offers a possible explanation for the opposite correlations between intra-tumoral Tregs and survival, associated with different types of cancer. The complexity involved with the selection of a preferred marker, including the effect of variability, is presented and discussed. The lymphocytes frequency ratio is proposed as the marker of choice in most types of cancer. The ratio correlates directly with survival, irrespective of cancer type and is also less variable than the frequencies of each of the two lymphocytes, if these frequencies correlate with each other in the tumor microenvironment. However, if the frequency of one of the two lymphocytes is highly variable, abandoning the ratio in favor of the lymphocyte with less variable frequency will improve correlation with survival, especially when the intra-tumoral frequencies of the two species are inversely correlated. It is plausible, that the best prognostic marker selected this way, will be also be the best predictor of checkpoint inhibitor therapy success.

Association of tumor deposits with tumor-infiltrating lymphocytes and prognosis in gastric cancer

Background

To investigate the relationship between tumor deposits (TDs) with the clinicopathological characteristics tumor-infiltrating lymphocytes (TILs) and prognosis of gastric cancer. Further analysis was done on the relationship between the number and maximum diameter of TDs with the clinicopathological characteristics and prognosis of gastric cancer.

Methods

The pathological findings of 369 patients with gastric cancer were retrospectively analyzed to observe the expression of TDs and the levels of stromal TILs. The relationship between TDs, clinicopathological characteristics, and levels of stromal TILs was compared using the chi-square test. Kaplan-Meier was used for survival analysis, and the log-rank test was used to determine the relationship between TDs and disease-free survival, cancer-specific survival, and overall survival. The prognostic value of TDs was assessed using multivariate Cox proportional hazards regression analysis. For further analysis, the optimal cutoff values for the number and maximum diameter of TDs were selected based on the receiver operating characteristic (ROC) curve.

Results

TDs were significantly associated with sex, lymphovascular invasion, perineural invasion, pathological T,N stage, and clinical stage (all P < 0.05). TILs levels are lower in TDs(+) group and higher in TDs(−) group. Compared with TDs(−) groups, TDs(+) group had poor disease-free survival, cancer-specific survival, and overall survival. TDs are negatively correlated with TILs, and TILs levels are lower in TDs(+) group and higher in TDs(−) group (P < 0.05). The samples are divided into the number of TDs (< 4 and ≥ 4) and the maximum diameter of TDs (< 7 mm and ≥ 7 mm). The number of TDs was significantly associated with pathological N stage (P < 0.05). The maximum diameter of TDs was significantly correlated with Lauren classification (P < 0.05) .TDs ≥ 4 had lower DFS, CSS, and OS (P < 0.05). The maximum diameter of TDs was not statistically significant with prognosis (P > 0.05).

Conclusion

TDs are independent prognosis predictors of gastric cancer. In the tumor microenvironment, TDs and TILs interact with each other to regulate the development of gastric cancer, thus affecting gastric cancer prognosis of patients. The number of TDs ≥ 4 has a worse prognosis compared to the number of TDs < 4.

Differences in tumor-infiltrating lymphocyte density and prognostic factors for breast cancer by patient age

Background

Lymphocytes that surround cancer participate in tumor-related immune responses and are called tumor-infiltrating lymphocytes (TILs). Several recent reports suggest TILs index the tumor microenvironment and predict the therapeutic effect of chemotherapy. However, only few studies have studied the relationship between age and TILs. Aging reduces host immunity, and we predict that it may also affect TILs. Thus, we hypothesized that older breast cancer (BC) patients may have low TIL density than younger BC patients. Here, we retrospectively analyzed the differences in TILs by age and the therapeutic effects of preoperative chemotherapy (POC) in BC patients who were aged either less than 45 years or more than 60 years.

Methods

We retrospectively examined the data of 356 breast cancer patients who underwent POC, including 75 patients aged ≤ 45 years and 116 patients aged > 60 years. Using pre-treatment needle biopsy specimens, TIL density was compared for each age group by Student’s t-test. After analyzing different factors that affect TIL density, prognostic factors were also examined.

Results

Older patients with triple-negative BC had significantly lower TIL density than younger patients, while in human epidermal growth factor receptor 2 (HER2)-enriched BC, TIL density was significantly higher in the younger age group than that in the older age group. In addition, younger patients with HER2-rich breast cancer showed significantly higher complete pathological response rates than older patients with HER2-rich BC. In addition, significant differences in overall survival were observed among these patients with triple-negative BC.

Conclusions

Our study suggests that younger BC patients possess significantly higher TIL density than older patients. These differences may influence the therapeutic efficacy in highly immunogenic subtypes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02513-5.