Colon cancer and the immune system: The role of tumor invading T cells

Cross-Talk Between Cancer and Its Cellular Environment-A Role in Cancer Progression

The tumor microenvironment is a dynamic and complex three-dimensional network comprising the extracellular matrix and diverse non-cancerous cells, including fibroblasts, adipocytes, endothelial cells and various immune cells (lymphocytes T and B, NK cells, dendritic cells, monocytes/macrophages, myeloid-derived suppressor cells, and innate lymphoid cells). A constantly and rapidly growing number of studies highlight the critical role of these cells in shaping cancer survival, metastatic potential and therapy resistance. This review provides a synthesis of current knowledge on the modulating role of the cellular microenvironment in cancer progression and response to treatment.

Spotting the clues: cluster of differentiation-a perspective of immune response intertwined with dysautonomia in colon cancer - a prospective cohort study

Dysautonomia, a parasympathetic-sympathetic imbalance, has clinical and public health consequences. Colon neoplasm is linked to dysautonomia through a complex interplay between the two conditions. In this prospective cohort study, we evaluated 18 patients divided into three groups: six patients with both colon cancer and dysautonomia, six patients with colon cancer without dysautonomia, and six patients with dysautonomia only (control group). Dysautonomia was defined by the presence of orthostatic hypotension, a non-increased or dropped heart rate, and various autonomic symptoms. During abdominal surgery, tissue samples from the celiac ganglion were collected and analyzed using immunohistochemistry (IHC). Our findings revealed a significant correlation between IHC marker expression in colon cancer and dysautonomia (control) (r = 0.927, P = 0.008). ANOVA results confirmed that the model was significant and that the dysautonomia group (control) had a significant effect on the independent variables (colon cancer or colon cancer + dysautonomia). The study proposes that a shared immunological mechanism underlies both dysautonomia and colon cancer, suggesting that the immune system plays a crucial role in the development or progression of these two conditions.

Identification of macrophage-related molecular subgroups and risk signature in colorectal cancer based on a bioinformatics analysis

Macrophages play a crucial role in tumor initiation and progression, while macrophage-associated gene signature in colorectal cancer (CRC) patients has not been investigated. Our study aimed to identify macrophage-related molecular subgroups and develop a macrophage-related risk model to predict CRC prognosis. The mRNA expression profile and clinical information of CRC patients were obtained from TCGA and GEO databases. CRC patients from TCGA were divided into high and low macrophage subgroups based on the median macrophage score. The ESTIMATE and CIBERSORT algorithms were used to assess immune cell infiltration between subgroups. GSVA and GSEA analyses were performed to investigate differences in enriched pathways between subgroups. Univariate and LASSO Cox regression were used to build a prognostic risk model, which was further validated in the GSE39582 dataset. A high macrophage score subgroup was associated with poor prognosis, highly activated immune-related pathways and an immune-active microenvironment. A total of 547 differentially expressed macrophage-related genes (DEMRGs) were identified, among which seven genes (including RIMKLB, UST, PCOLCE2, ZNF829, TMEM59L, CILP2, DTNA) were identified by COX regression analyses and used to build a risk score model. The risk model shows good predictive and diagnostic values for CRC patients in both TCGA and GSE39852 datasets. Furthermore, multivariate Cox regression analysis showed that the risk score was an independent risk factor for overall survival in CRC patients. Our findings provided a novel insight into macrophage heterogeneity and its immunological role in CRC. This risk score model may serve as an effective prognostic tool and contribute to personalised clinical management of CRC patients.

Prognostic cellular senescence-related lncRNAs patterns to predict clinical outcome and immune response in colon cancer

Background

Cellular senescence (CS) is believed to be a major factor in the evolution of cancer. However, CS-related lncRNAs (CSRLs) involved in colon cancer regulation are not fully understood. Our goal was to create a novel CSRLs prognostic model for predicting prognosis and immunotherapy and exploring its potential molecular function in colon cancer.

Methods

The mRNA sequencing data and relevant clinical information of GDC TCGA Colon Cancer (TCGA-COAD) were obtained from UCSC Xena platform, and CS-associated genes was acquired from the CellAge website. Pearson correlation analysis was used to identify CSRLs. Then we used Kaplan-Meier survival curve analysis and univariate Cox analysis to acquire prognostic CSRL. Next, we created a CSRLs prognostic model using LASSO and multivariate Cox analysis, and evaluated its prognostic power by Kaplan-Meier and ROC curve analysis. Besides, we explored the difference in tumor microenvironment, somatic mutation, immunotherapy, and drug sensitivity between high-risk and low-risk groups. Finally, we verified the functions of MYOSLID in cell experiments.

Results

Three CSRLs (AC025165.1, LINC02257 and MYOSLID) were identified as prognostic CSRLs. The prognostic model exhibited a powerful predictive ability for overall survival and clinicopathological features in colon cancer. Moreover, there was a significant difference in the proportion of immune cells and the expression of immunosuppressive point biomarkers between the different groups. The high-risk group benefited from the chemotherapy drugs, such as Teniposide and Mitoxantrone. Finally, cell proliferation and CS were suppressed after MYOSLID knockdown.

Conclusion

CSRLs are promising biomarkers to forecast survival and therapeutic responses in colon cancer patients. Furthermore, MYOSLID, one of 3-CSRLs in the prognostic model, could dramatically regulate the proliferation and CS of colon cancer.

Current and Future Trends of Colorectal Cancer Treatment: Exploring Advances in Immunotherapy

Cancer of the colon and rectum (CRC) has been identified among the three most prevalent types of cancer and cancer-related deaths for both sexes. Even though significant progress in surgical and chemotherapeutic techniques has markedly improved disease-free and overall survival rates in contrast to those three decades ago, recent years have seen a stagnation in these improvements. This underscores the need for new therapies aiming to augment patient outcomes. A number of emerging strategies, such as immune checkpoint inhibitors (ICIs) and adoptive cell therapy (ACT), have exhibited promising outcomes not only in preclinical but also in clinical settings. Additionally, a thorough appreciation of the underlying biology has expanded the scope of research into potential therapeutic interventions. For instance, the pivotal role of altered telomere length in early CRC carcinogenesis, leading to chromosomal instability and telomere dysfunction, presents a promising avenue for future treatments. Thus, this review explores the advancements in CRC immunotherapy and telomere-targeted therapies, examining potential synergies and how these novel treatment modalities intersect to potentially enhance each other's efficacy, paving the way for promising future therapeutic advancements.

Isolation and high-dimensional flow cytometric analysis of tumor-infiltrating leukocytes in a mouse model of colorectal cancer

Colorectal cancer (CRC) is a complex and heterogeneous disease characterized by dysregulated interactions between tumor cells and the immune system. The tumor microenvironment plays a pivotal role in cancer initiation as well as progression, with myeloid immune cells such as dendritic cell and macrophage subsets playing diverse roles in cancer immunity. On one hand, they exert anti-tumor effects, but they can also contribute to tumor growth. The AOM/DSS colitis-associated cancer mouse model has emerged as a valuable tool to investigate inflammation-driven CRC. To understand the role of different leukocyte populations in tumor development, the preparation of single cell suspensions from tumors has become standard procedure for many types of cancer in recent years. However, in the case of AOM/DSS-induced colorectal tumors, this is still challenging and rarely described. For one, to be able to properly distinguish tumor-associated immune cells, separate processing of cancerous and surrounding colon tissue is essential. In addition, cell yield, due to the low tumor mass, viability, as well as preservation of cell surface epitopes are important for successful flow cytometric profiling of tumor-infiltrating leukocytes. Here we present a fast, simple, and economical step-by-step protocol for isolating colorectal tumor-associated leukocytes from AOM/DSS-treated mice. Furthermore, we demonstrate the feasibility of this protocol for high-dimensional flow cytometric identification of the different tumor-infiltrating leukocyte populations, with a specific focus on myeloid cell subsets.

Prognosis and immunotherapy response prediction based on M2 macrophage-related genes in colon cancer

BACKGROUND

M2 macrophage were revealed to play a crucial role in immune evasion and immunotherapies. This study aims to explore the potential significance of M2 macrophage-related genes in colon adenocarcinoma (COAD) by analysizing the transcriptome data in a comprehensive way.

METHODS

We collected RNA-sequencing (RNA-seq) data of COAD from The Cancer Genome Atlas (TCGA) and Gene Expression Ominibus (GEO) databases. We calculated the immune infiltration scores of every sample using CIBERSORT algorithm. Through weighted gene co-expression network analysis (WGCNA), we picked out M2 macrophage-related genes. With these genes we screened out prognosis related genes which were utilized to construct a signature to assess the prognosis of patients. To extend the potential application of the signature, we also calculated the correlations with immune infiltration. Finally, we applied techniques such as quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunoblotting (Western Blotting) to validate the RNF32 gene in cellular in vitro assays.

RESULTS

Seven M2 macrophage-related genes signature was constructed, which was an excellent prognostic predictor in two independent groups. The high-risk group showed lower immune infiltration and poorer response to immunotherapies than those of the low-risk group. The cell vitro experiments showed that the expression level of RNF32 was upregulated in colon cancer cell lines compared with normal cell lines. Moreover, we found that RNF32 may promote the proliferation, migration and invasion of cancer cells in vitro by inhibiting apoptosis.

CONCLUSION

A novel M2 macrophage-related gene signature affects the prognosis and immune characteristics of colon cancer.

Current perspective on biological properties of plasmacytoid dendritic cells and dysfunction in gut

Plasmacytoid dendritic cells (pDCs), a subtype of DC, possess unique developmental, morphological, and functional traits that have sparked much debate over the years whether they should be categorized as DCs. The digestive system has the greatest mucosal tissue overall, and the pDC therein is responsible for shaping the adaptive and innate immunity of the gastrointestinal tract, resisting pathogen invasion through generating type I interferons, presenting antigens, and participating in immunological responses. Therefore, its alleged importance in the gut has received a lot of attention in recent years, and a fresh functional overview is still required. Here, we summarize the current understanding of mouse and human pDCs, ranging from their formation and different qualities compared with related cell types to their functional characteristics in intestinal disorders, including colon cancer, infections, autoimmune diseases, and intestinal graft-versus-host disease. The purpose of this review is to convey our insights, demonstrate the limits of existing research, and lay a theoretical foundation for the rational development and use of pDCs in future clinical practice.

Interleukins (Cytokines) as Biomarkers in Colorectal Cancer: Progression, Detection, and Monitoring

Cancer is the primary cause of death in economically developed countries and the second leading cause in developing countries. Colorectal cancer (CRC) is the third most common cause of cancer-related deaths worldwide. Risk factors for CRC include obesity, a diet low in fruits and vegetables, physical inactivity, and smoking. CRC has a poor prognosis, and there is a critical need for new diagnostic and prognostic biomarkers to reduce related deaths. Recently, studies have focused more on molecular testing to guide targeted treatments for CRC patients. The most crucial feature of activated immune cells is the production and release of growth factors and cytokines that modulate the inflammatory conditions in tumor tissues. The cytokine network is valuable for the prognosis and pathogenesis of colorectal cancer as they can aid in the cost-effective and non-invasive detection of cancer. A large number of interleukins (IL) released by the immune system at various stages of CRC can act as "biomarkers". They play diverse functions in colorectal cancer, and include IL-4, IL-6, IL-8, IL-11, IL-17A, IL-22, IL-23, IL-33, TNF, TGF-β, and vascular endothelial growth factor (VEGF), which are pro-tumorigenic genes. However, there are an inadequate number of studies in this area considering its correlation with cytokine profiles that are clinically useful in diagnosing cancer. A better understanding of cytokine levels to establish diagnostic pathways entails an understanding of cytokine interactions and the regulation of their various biochemical signaling pathways in healthy individuals. This review provides a comprehensive summary of some interleukins as immunological biomarkers of CRC.

Pathological Characteristics, Prognostic Determinants and the Outcome of Patients Diagnosed with Colorectal Adenocarcinoma at the University Teaching Hospital of Kigali

Worldwide, colorectal cancer (CRC) is the second most diagnosed cancer in female and the third in men, arising from the epithelium of the colorectum. It is known that colorectal cancer is common in developed countries than in developing countries which may be due to inaccurate data on the existence of the disease in that region combined with embracing western lifestyle expressed by the current trend of changes in cultural, social, and lifestyle practices playing a major part in the etiology of CRC. The aim of this study was to document epidemiological, pathological characteristics, and prognostics determinants of patients diagnosed with CRC in Rwanda. The data from patients' files and reviewed glass slides for 101 cases all from Kigali University Teaching Hospital (CHUK) were statistically analyzed and patient characteristics were described as mean and frequency accordingly. Comparisons were performed using chi square tests, Fisher's exact test and odds ratio with 95% confidence interval (CI). Survival curves were plotted using the Kaplan-Meier method, and log-rank test was used to assess the statistical differences in the observed survival curves by each categorical variable. A P value < 0.05 was considered statistically significant. Statistical analyses were performed using Statistical Product and Service Solutions (SPSS), GraphPad Prism, and MedCalc, accordingly. Mean age of the participants was 54.26 years, the main symptom was rectal bleeding (46.5%), rectal adenocarcinoma NOS represented 40.6%, conventional adenocarcinoma was 60.4%, most tumors were of Grade II (54.5%), most common stage was pT3N0 (20.8%), resection margins were free at 71.3%, lympho-vascular invasion was 49.5% of cases, a high immune response was in 71.3% of cases and of 101cases, and 55.4% were still alive at the end of the data collection, with 29.3% of patients have overall survival of 5 years. Prognostic determinants also affect the outcome in this study and overall survival period was 3 years for CRC diagnosed in Rwanda.

Construction of a Pearson- and MIC-Based Co-expression Network to Identify Potential Cancer Genes

The weighted gene co-expression network analysis (WGCNA) method constructs co-expressed gene modules based on the linear similarity between paired gene expressions. Linear correlations are the main form of similarity between genes, however, nonlinear correlations still existed and had always been ignored. We proposed a modified network analysis method, WGCNA-P + M, which combines Pearson's correlation coefficient and the maximum information coefficient (MIC) as the similarity measures to assess the linear and nonlinear correlations between genes, respectively. Taking two real datasets, GSE44861 and liver hepatocellular carcinoma (TCGA-LIHC), as examples, we compared the gene modules constructed by WGCNA-P + M and WGCNA from four perspectives: the "Usefulness" score, GO enrichment analysis on genes in the gray module, prediction performance of the top hub gene, survival analysis and literature reports on different hub genes. The results showed that the modules obtained by WGCNA-P + M are more biological meaningful, the hub genes obtained from WGCNA-P + M have more potential cancer genes.

Hsa_circ_0136666 activates Treg-mediated immune escape of colorectal cancer via miR-497/PD-L1 pathway

PURPOSE

In the rankings of cancer mortality and incidence worldwide, colorectal cancer ranks fourth and the third, respectively. Circular RNA hsa_circ_0136666 (hsa_circ_0136666) is reported to participate in the growth of colorectal cancer. However, the mechanism by which hsa_circ_0136666 regulates the tumorigenesis of colorectal cancer needs to be further explored. In this study, we report here the role of hsa_circ_0136666 in the aberrant activation of Treg cells and immune evasion of tumor cells, providing a new strategy for the treatment of colorectal cancer.

METHODS

Western blotting assay and qRT-PCR assay were used to determine protein and mRNA expression levels. Dual-luciferase reporter assay was used to evaluate the targeted regulatory relationship. RNA immunoprecipitation was used to detect RNA binding. Colony formation assay was utilized to measure the cell proliferation. Flow cytometry was used to assess cell apoptosis. Xenograft model was setup to evaluate tumor growth.

RESULTS

The results showed that hsa_circ_0136666 and PD-L1 was increased in colorectal cancer cells while miR-497 was decreased in colorectal cancer cells when compared with normal colon epithelial cell line. Hsa_circ_0136666 was demonstrated to directly target miR-497, which also regulated PD-L1 by binding to its 3'UTR. Further mechanistic studies identified that hsa_circ_0136666 controlled cell proliferation and apoptosis via targeting miR-497 and regulating PD-L1 expression. Of note, hsa_circ_0136666 stimulated Treg cells mediated by miR-497/PD-L1 axis and its downstream signal pathway in Treg cells. Finally, hsa_circ_0136666 was found to accelerate the tumor growth in vivo.

CONCLUSIONS

Our findings demonstrated that hsa_circ_0136666 promoted the expression of PD-L1 by inhibiting miR-497 level in colorectal cancer, thus inducing the activation of Treg cells and leading to the immune escape of tumor, providing a novel mechanistic insight into the pathogenesis of colorectal cancer.

An Immune-Clinical Prognostic Index (ICPI) for Patients With De Novo Follicular Lymphoma Treated With R-CHOP/CHOP Chemotherapy

Purpose

Although the role of tumor-infiltrating T cells in follicular lymphoma (FL) has been reported previously, the prognostic value of peripheral blood T lymphocyte subsets has not been systematically assessed. Thus, we aim to incorporate T-cell subsets with clinical features to develop a predictive model of clinical outcome.

Methods

We retrospectively screened a total of 1,008 patients, including 252 newly diagnosed de novo FL patients with available peripheral blood T lymphocyte subsets who were randomized to different sets (177 in the training set and 75 in the internal validation set). A nomogram and a novel immune-clinical prognostic index (ICPI) were established according to multivariate Cox regression analysis for progression-free survival (PFS). The concordance index (C-index), Akaike’s information criterion (AIC), and likelihood ratio chi-square were employed to compare the ICPI’s discriminatory capability and homogeneity to that of FLIPI, FLIPI2, and PRIMA-PI. Additional external validation was performed using a dataset (n = 157) from other four centers.

Results

In the training set, multivariate analysis identified five independent prognostic factors (Stage III/IV disease, elevated lactate dehydrogenase (LDH), Hb <120g/L, CD4+ <30.7% and CD8+ >36.6%) for PFS. A novel ICPI was established according to the number of risk factors and stratify patients into 3 risk groups: high, intermediate, and low-risk with 4-5, 2-3, 0-1 risk factors respectively. The hazard ratios for patients in the high and intermediate-risk groups than those in the low-risk were 27.640 and 2.758. The ICPI could stratify patients into different risk groups both in the training set (P < 0.0001), internal validation set (P = 0.0039) and external validation set (P = 0.04). Moreover, in patients treated with RCHOP-like therapy, the ICPI was also predictive (P < 0.0001). In comparison to FLIPI, FLIPI2, and PRIMA-PI (C-index, 0.613-0.647), the ICPI offered adequate discrimination capability with C-index values of 0.679. Additionally, it exhibits good performance based on the lowest AIC and highest likelihood ratio chi-square score.

Conclusions

The ICPI is a novel predictive model with improved prognostic performance for patients with de novo FL treated with R-CHOP/CHOP chemotherapy. It is capable to be used in routine practice and guides individualized precision therapy.

Identification of macrophage related gene in colorectal cancer patients and their functional roles

BACKGROUND

Recent scientific research has enabled the identification of macrophages related-genes (MaRG), which play a key role in the control of the immune microenvironment in many human cancers. However, the functional role of MaRGs in human tumors is ill-defined. Herein, we aimed at bioinformatically exploring the molecular signatures of MaRGs in colorectal cancer.

METHODS

A list of MaRGs was generated and their differential expression was analyzed across multiple datasets downloaded from the publicly available functional genomics database Gene Expression Omnibus. The weighted gene co-expression network analysis (WGCNA) was also applied to identify the partner genes of these MaRGs in colorectal cancer.

RESULTS

After integration of the results from analyses of different datasets, we found that 29 differentially expressed MaRGs (DE-MaRGs) could be considered as CRC-related genes as obtained from the WGCNA analysis. These genes were functionally involved in positive regulation of DNA biosynthetic process and glutathione metabolism. Protein-protein interaction network analysis indicated that PDIA6, PSMA1, PRC1, RRM2, HSP90AB1, CDK4, MCM7, RFC4, and CCT5 were the hub MaRGs. The LASSO approach was used for validating the 29 MaRGs in TCGA-COAD and TCGA-READ data and the results showed that ten among the 29 genes could be considered as MaRGs significantly involved in CRC. The maftools analysis showed that MaRGs were mutated at varying degrees. The nomogram analysis indicated the correlation of these MaRGs with diverse clinical features of CRC patients.

CONCLUSIONS

Conclusively, the present disclosed a signature of MaRGs as potential key regulators involved in CRC pathogenesis and progression. These findings contribute not only to the understanding of the molecular mechanism of CRC pathogenesis but also to the development of adequate immunotherapies for CRC patients.

Therapeutic effects of dihydroartemisinin in multiple stages of colitis-associated colorectal cancer

Colitis-associated colorectal cancer (CAC) develops from chronic intestinal inflammation. Dihydroartemisinin (DHA) is an antimalarial drug exhibiting anti-inflammatory and anti-tumor effects. Nonetheless, the therapeutic effects of DHA on CAC remain unestablished.

Methods: Mice were challenged with azoxymethane (AOM) and dextran sulfate sodium (DSS) to establish CAC models. DHA was administered via oral gavage in different stages of CAC models. Colon and tumor tissues were obtained from the AOM/DSS models to investigate inflammatory responses and tumor development. Inflammatory cytokines in the murine models were detected through qRT-PCR and ELISA. Toll-like receptor 4 (TLR4) signaling-related proteins were detected by western blot. Macrophage infiltration was measured using immunostaining analysis, and apoptosis in the colon cancer cells was detected by flow cytometry and western blot.

Results: DHA inhibited inflammatory responses in the early stage of the AOM/DSS model and subsequent tumor formation. In the early stage, DHA reversed macrophage infiltration in colon mucosa and decreased the expression of pro-inflammatory cytokines. DHA inhibited the activation of macrophage by suppressing the TLR4 signal pathway. In the late stage of CAC, DHA inhibited tumor growth by enhancing cell cycle arrest and apoptosis in tumor cells. Administration of DHA during the whole period of the AOM/DSS model generated an addictive effect based on the inhibition of inflammation and tumor growth, thereby improving the therapeutic effect of DHA on CAC.

Conclusion: Our study indicated that DHA could be a potent agent in managing the initiation and development of CAC without obvious side effects, warranting further clinical translation of DHA for CAC treatment.

Immunobiology of cholangiocarcinoma

Cholangiocarcinoma (CCA) represents a heterogeneous group of epithelial tumours that are classified according to anatomical location as intrahepatic (iCCA), perihilar (pCCA), or distal (dCCA). Although surgical resection and liver transplantation following neoadjuvant therapy are potentially curative options for a subset of patients with early-stage disease, the currently available medical therapies for CCA have limited efficacy. Immunotherapeutic strategies such as immune checkpoint blockade (ICB) harness the host immune system to unleash an effective and durable antitumour response in a subset of patients with a variety of malignancies. However, response to ICB monotherapy has been relatively disappointing in CCA. CCAs are desmoplastic tumours with an abundant tumour immune microenvironment (TIME) that contains immunosuppressive innate immune cells such as tumour-associated macrophages and myeloid-derived suppressor cells. A subset of CCAs may be classified as immune 'hot' tumours with a high density of CD8+ T cells and enhanced expression of immune checkpoint molecules. Immune 'hot' tumour types are associated with higher response rates to ICB. However, the suboptimal response rates to ICB monotherapy in human clinical trials of CCA imply that the preponderance of CCAs are immune 'cold' tumours with a non-T cell infiltrated TIME. An enhanced comprehension of the immunobiology of CCA, particularly the innate immune response to CCA, is essential in the effort to develop effective combination immunotherapeutic strategies that can target a larger subset of CCAs.

BioTarget: A Computational Framework Identifying Cancer Type Specific Transcriptional Targets of Immune Response Pathways

Transcriptome data can provide information on signaling pathways active in cancers, but new computational tools are needed to more accurately quantify pathway activity and identify tissue-specific pathway features. We developed a computational method called “BioTarget” that incorporates ChIP-seq data into cellular pathway analysis. This tool relates the expression of transcription factor TF target genes (based on ChIP-seq data) with the status of upstream signaling components for an accurate quantification of pathway activity. This analysis also reveals TF targets expressed in specific contexts/tissues. We applied BioTarget to assess the activity of TBX21 and GATA3 pathways in cancers. TBX21 and GATA3 are TF regulators that control the differentiation of T cells into Th1 and Th2 helper cells that mediate cell-based and humoral immune responses, respectively. Since tumor immune responses can impact cancer progression, the significance of our pathway scores should be revealed by effective patient stratification. We found that low Th1/Th2 activity ratios were associated with a significantly poorer survival of stomach and breast cancer patients, whereas an unbalanced Th1/Th2 response was correlated with poorer survival of colon cancer patients. Lung adenocarcinoma and lung squamous cell carcinoma patients had the lowest survival rates when both Th1 and Th2 responses were high. Our method also identified context-specific target genes for TBX21 and GATA3. Applying the BioTarget tool to BCL6, a TF associated with germinal center lymphocytes, we observed that patients with an active BCL6 pathway had significantly improved survival for breast, colon, and stomach cancer. Our findings support the effectiveness of the BioTarget tool for transcriptome analysis and point to interesting associations between some immune-response pathways and cancer progression.

Immune inflammation indicators in anal cancer patients treated with concurrent chemoradiation: training and validation cohort with online calculator (ARC: Anal Cancer Response Classifier)

Background: In anal cancer, there are no markers nor other laboratory indexes that can predict prognosis and guide clinical practice for patients treated with concurrent chemoradiation. In this study, we retrospectively investigated the influence of immune inflammation indicators on treatment outcome of anal cancer patients undergoing concurrent chemoradiotherapy.

Methods: All patients had a histologically proven diagnosis of squamous cell carcinoma of the anal canal/margin treated with chemoradiotherapy according to the Nigro’s regimen. Impact on prognosis of pre-treatment systemic index of inflammation (SII) (platelet x neutrophil/lymphocyte), neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) were analyzed.

Results: A total of 161 consecutive patients were available for the analysis. Response to treatment was the single most important factor for progression-free survival (PFS) and overall survival (OS). At univariate analysis, higher SII level was significantly correlated to lower PFS (p<0.01) and OS (p=0.046). NLR level was significantly correlated to PFS (p=0.05), but not to OS (p=0.06). PLR level significantly affected both PFS (p<0.01) and OS (p=0.02). On multivariate analysis pre-treatment, SII level was significantly correlated to PFS (p=0.0079), but not to OS (p=0.15). We developed and externally validated on a cohort of 147 patients a logistic nomogram using SII, nodal status and pre-treatment Hb levels. Results showed a good predictive ability with C-index of 0.74. An online available calculator has also been developed.

Conclusion: The low cost and easy profile in terms of determination and reproducibility make SII a promising tool for prognostic assessment in this oncological setting.

Prognostic impact of programmed cell death ligand 1 (PD-L1) expression and its association with epithelial-mesenchymal transition in extrahepatic cholangiocarcinoma

Extrahepatic cholangiocarcinoma (eCCA) has a poor prognosis. Although the possibility of immunotherapy has been studied, immune checkpoint molecules such as programmed death ligand 1 (PD-L1) in eCCA are not well understood. Epithelial-mesenchymal transition (EMT) has recently been shown to regulate PD-L1 expression. Our aims were to assess the clinicopathological significance of tumor-infiltrating lymphocytes (TILs) and tumor PD-L1 expression in eCCA and to compare these immune responses with EMT marker expression. In this retrospective study, we conducted immunohistochemical analyses for 117 patients with eCCA. We stained for CD4, CD8, Foxp3, and PD-L1 as markers reflecting local immune responses, and for E-cadherin, N-cadherin, vimentin, ZEB1, ZEB2, SNAIL, and TWIST as markers associated with EMT. High numbers of CD4+ and CD8+ TILs correlated with node-negative (P = 0.009 and P = 0.046, respectively) and low SNAIL expression (P = 0.016 and P = 0.022, respectively). High PD-L1 expression was associated with poor histopathological classification (P = 0.034), and low E-cadherin (P = 0.001), high N-cadherin (P = 0.044), high vimentin (P < 0.001) and high ZEB1 (P = 0.036) expression. Multivariate analysis showed that CD4+ TILs, PD-L1 expression and N-cadherin expression were independent prognostic factors (hazard ratio (HR) = 0.61; 95% confidence interval (CI) = 0.38-1.00; HR=4.27; 95% CI = 1.82-9.39; HR = 2.20; 95% CI = 1.18-3.92, respectively). These findings could help to identify potential biomarkers for predicting not only the prognosis, but also the therapeutic response to immunotherapy for eCCA.

Regulation of inflammatory factors by double-stranded RNA receptors in breast cancer cells

Malignant cells are not the only components of a tumor mass since other cells (e.g., fibroblasts, infiltrating leukocytes and endothelial cells) are also part of it. In combination with the extracellular matrix, all these cells constitute the tumor microenvironment. In the last decade the role of the tumor microenvironment in cancer progression has gained increased attention and prompted efforts directed to abrogate its deleterious effects on anti-cancer therapies. The immune system can detect and attack tumor cells, and tumor-infiltrating lymphocytes (particularly CD8 T cells) have been associated with improved survival or better response to therapies in colorectal, melanoma, breast, prostate and ovarian cancer patients among others. Contrariwise, tumor-associated myeloid cells (myeloid-derived suppressor cells [MDSCs], dendritic cells [DCs], macrophages) or lymphoid cells such as regulatory T cells can stimulate tumor growth via inhibition of immune responses against the tumor or by participating in tumor neoangiogenesis. Herewith we analyzed the chemokine profile of mouse breast tumors regarding their capacity to generate factors capable of attracting and sequestering DCs to their midst. Chemoattractants from tumors were investigated by molecular biology and immunological techniques and tumor infiltrating DCs were investigated for matched chemokine receptors. In addition, we investigated the inflammatory response of breast cancer cells, a major component of the tumor microenvironment, to double-stranded RNA stimulation. By using molecular biology techniques such as qualitative and quantitative PCR, PCR arrays, and immunological techniques (ELISA, cytokine immunoarrays) we examined the effects of dsRNA treatment on the cytokine secretion profiles of mouse and human breast cancer cells and non-transformed cells. We were able to determine that tumors generate chemokines that are able to interact with receptors present on the surface of tumor infiltrating DCs. We observed that PRR signaling is able to modify the production of chemokines by breast tumor cells and normal breast cells, thereby constituting a possible player in shaping the profile of the leukocyte population in the TME.

Prognostic role of the lymphocyte-to-monocyte ratio in colorectal cancer: An up-to-date meta-analysis

BACKGROUND

Although previous meta-analyses have proved that lymphocyte-to-monocyte ratio (LMR) is a prognostic factor in solid cancers, its prognostic role in colorectal cancer (CRC) remains controversial. We, therefore, conducted this up-to-date meta-analysis to evaluate the prognostic role of the LMR in CRC.

METHODS

A systematic search was performed in PubMed and Embase for relevant studies in November 2016. Article assessing the prognostic role of LMR in CRC was enrolled in this meta-analysis. Data and characteristics of each study were extracted. A meta-analysis was performed to generate pooled hazard ratio (HR) and 95% confidence intervals (95% CIs) for overall survival (OS) and disease-free survival. Begg funnel plot was used to evaluate publication bias.

RESULTS

Eleven studies published between 2014 and 2016 with a total of 9045 patients were enrolled in this meta-analysis. Our findings indicated that a low LMR predicted a worse OS (HR 1.57, 95% CI 1.30-1.90, P < .001) and disease-free survival. (HR 1.25, 95% CI 1.13-1.39, P < .001) for patients with CRC. Subgroup analyses according to stage (I-III and IV) and LMR cut-off value (<3.00 and ≥3.00) showed a significant prognostic value of LMR on OS. Begg funnel plot showed that publication bias existed in this meta-analysis.

CONCLUSIONS

This up-to-date meta-analysis shows that a low LMR is associated with poor survival in patients with CRC, although the publication bias is existed. Large-sample multicenter prospective cohort is needed to assess the role of the LMR in CRC patients.

Activation or suppression of the immune response mediators in biliary tract cancer (BTC) patients: a systematic review and meta-analysis

Background: Infiltration of immune cells and immune microenvironment determine the proliferative activity of the tumor and metastasis. The aim of this study was to analyze the influence of activation or suppression of the immune response mediators on the prognosis of biliary tract cancer (BTC). Methods: We searched Pubmed, Web of Science, Embase and The Cochrane Library for relevant literatures until June 2016. The quality of studies was assessed by QUADAS-2 and NOS tools. Forest and funnel plots and all statistical analyses were generated by using Review Manager 5.3. The bias of included studies was estimated by Egger's test using Meta R package. Results: A total of 2339 patients from 12 studies were finally enrolled in this meta-analysis. Patients with high expression of immune active factors, intraepithelial tumor-infiltrating CD4+ , CD8+, and Foxp3+ T lymphocytes, MHC I, NKG2D, showed a better overall survival (OS) than those with low expression (HR=0.52, 95% CI=0.41-0.67, P<0.00001). On the contrary, the high expression of immune suppressive factors (CD66b+ neutrophils, Neutrophil-lymphocyte ratio, Intratumoral IL-17+ cells and PD-1+/CD8+ TILs) was significantly associated with poor OS (HR=1.79, 95% CI=1.44-2.22, P<0.00001). A further analysis of therapies targeting tumor microenvironment modulation showed that the median progression free survival (PFS) for BTC patients who received adjuvant immunotherapy was longer than those who received surgery or chemotherapy alone, and the estimated pooled mean difference demonstrated a highly significant improvement (MD =2.33; 95% CI: 0.63-4.02, P=0.007). The total effect of PFS and OS was statistically longer in experimental group, compared to patients in control groups, respectively (PFS: RR=1.25; 95% CI: 1.08-1.46, P=0.004; OS: RR=1.16; 95% CI: 1.07-1.27, P=0.0006). In subgroup meta-analysis of studies on 6-, 12- and 18-month PFS and OS, it showed that adjuvant immunotherapy could improve the 6-month PFS (RR=1.23; 95% CI: 1.05-1.44, P=0.009), and 6-month OS (RR=1.17; 95% CI: 1.06-1.30, P=0.002). Conclusions: So given the above issue, our meta-analysis confirmed that the level of immune mediators could be a predicative factor for prognosis of BTC patients, and immunotherapy regimens by modulating the tumor microenvironment was superior for enhancing median PFS, 6-month PFS and OS.

Relationship Between Lesions in Adenomatous Polyp-Dysplasia-Colorectal Cancer Sequence and Neutrophil-to-Lymphocyte Ratio

BACKGROUND The aim of our study was to evaluate all lesions in the adenoma-dysplasia-cancer sequence of the colon and to examine whether the neutrophil-to-lymphocyte ratio (NLR) can distinguish polyps indicating dysplasia and cancer. MATERIAL AND METHODS A total of 397 patients who had colonoscopic polypectomy between January 2010 and December 2014 were included in our retrospective study. The patients were divided into four groups: patients with hyperplastic polyps, patients with adenomatous polyps, patients with dysplasia, and patients with cancer. The NLR was calculated as a simple ratio indicating the relationship between counts of absolute neutrophil and absolute lymphocyte. RESULTS The NLR increased in line with the adenomatous polyp-dysplasia-cancer sequence, with the highest ratio established among cancer patients (2.05 (0.27-10), 2.34 (0.83-14.70) and 3.25 (0.81-10.0), respectively). The NLR was significantly higher among cancer patients than among patients with adenomatous polyps and hyperplastic polyps (p values were 0.001 and 0.004, respectively). The lymphocyte count of cancer patients was prominently lower when compared to those in groups with adenomatous polyps and hyperplastic polyps (p values were 0.001 and 0.003, respectively). The NLR was found to be significantly higher in patients with polyps larger than 10 mm [2.71 (0.90-14.70)] when compared to those with polyps smaller than 10 mm [2.28 (0.27-11.67)] (p<0.001). With the NLR threshold set at 2.20, it was possible to predict cancerous polyps with a sensitivity of 71.4% and a specificity of 52.5% (AUC: 0.665, 95% CI: 0.559-0.772, p=0.001). CONCLUSIONS NLR is a cheap, universally available, simple and reliable test that can help predict cancerous polyps. It can be used as a non-invasive test for monitoring polyps.

Prognostic role of the lymphocyte-to-monocyte ratio in patients undergoing resection for nonmetastatic rectal cancer

Lymphocyte-to-monocyte ratio (LMR) was associated with survival benefit in some types of cancer. The relationship between LMR and rectal cancer has not been investigated. We conducted a retrospective cohort study to assess the prognostic significance of LMR in patients with nonmetastatic rectal cancer. Patients with rectal cancer who underwent potentially curative resection between January 2009 and December 2013 were enrolled. The LMR was calculated from preoperative blood test by dividing the absolute lymphocyte counts by the absolute monocyte counts. The optimal cut-off value for LMR was calculated as the median value. On the basis of the cut-off value, patients were divided into 2 groups: low group and high group. A total of 543 patients with rectal cancer were eligible for this study. The median follow-up time for all patients was 55 months (range 6-85 months). The cut-off value of LMR was 5.13 and patients were divided into 2 groups: low group (LMR < 5.13) and high group (LMR ≥ 5.13). In the univariate and multivariate analysis, the LMR was not significantly associated with overall survival (OS) [hazard ratio (HR): 1.034, 95% confidence intervals (CIs): 0.682-1.566, P = 0.876]. When disease-free survival (DFS) was compared, univariate and multivariate analysis also indicated that the LMR was not significantly associated with DFS (HR: 0.988, 95% CI: 0.671-1.453, P = 0.950). In addition, in the subgroup analysis by tumor-node-metastasis stage, there existed no significance between LMR and OS and DFS. Although as an easy access and highly efficient laboratorial inflammatory marker, LMR cannot predict the prognosis of nonmetastatic rectal cancer patients.

Proximal signaling responses in peripheral T cells from colorectal cancer patients are affected by high concentrations of circulating prostaglandin E2

Patients with colorectal cancer (CRC) have been shown to have elevated levels of circulating prostaglandin E₂ (PGE₂) which promotes cancer progression and suppresses T cell immune responses. In this study we evaluated whether signaling responses in T lymphocytes obtained from peripheral blood of CRC patients were affected by the sustained exposure to increased levels of PGE₂. The phosphorylation status of an extended panel of proteins involved in downstream signaling cascades in T cells was profiled at a single cell level both in naïve and antigen-experienced cells after triggering T cell-, prostaglandin- and interleukin-2 receptors. Peripheral T cells from patients with elevated PGE₂ levels displayed aberrant T cell signaling responses downstream of the T cell receptor (assessed by reduced phosphorylation of CD3ζ and SLP76), and after triggering the IL-2 receptor (assessed by reduced phosphorylation of STAT5) when compared to T cells from CRC patients with lower levels of PGE₂ and T cells from healthy blood donors. This signaling study of circulating T cells from CRC patients indicates that increased systemic PGE₂ levels affect proximal T cell responses and confirms phospho-specific flow cytometry to be a valuable tool for revealing signaling signatures in immunological disorders.

Prognostic significance of neutrophil-to-lymphocyte ratio in rectal cancer: a meta-analysis

Background

Inflammatory responses play decisive roles in tumor development, immune surveillance, and responses to therapy. High neutrophil-to-lymphocyte ratio (NLR), as an inflammation index, has been reported to be a predictor for poor prognosis of various cancers. The purpose of this meta-analysis was to evaluate the prognostic value of NLR in patients with rectal cancer.

Methods

A comprehensive search of the literature was conducted through PubMed and EMBASE. Pooled hazard ratio (HR) with 95% confidence interval (CI) was used to evaluate the association between NLR and three outcomes: overall survival, disease-free survival, and recurrence-free survival.

Results

Seven cohorts involving 959 patients were included in this meta-analysis. Our pooled results demonstrated that elevated NLR was associated with poor overall survival (HR: 13.41, 95% CI: 4.90–36.72), disease-free survival (HR: 4.37, 95% CI: 2.33–8.19), and recurrence-free survival (HR: 3.64, 95% CI: 1.88–7.05).

Conclusion

An elevated NLR is a valuable and easily available prognostic marker for rectal cancer. It is associated with unfavorable overall survival, disease-free survival, and recurrence-free survival. NLR could be a useful candidate factor for making treatment decisions for individual patients with rectal cancer.

Cancer prevention and therapy through the modulation of the tumor microenvironment

Cancer arises in the context of an in vivo tumor microenvironment. This microenvironment is both a cause and consequence of tumorigenesis. Tumor and host cells co-evolve dynamically through indirect and direct cellular interactions, eliciting multiscale effects on many biological programs, including cellular proliferation, growth, and metabolism, as well as angiogenesis and hypoxia and innate and adaptive immunity. Here we highlight specific biological processes that could be exploited as targets for the prevention and therapy of cancer. Specifically, we describe how inhibition of targets such as cholesterol synthesis and metabolites, reactive oxygen species and hypoxia, macrophage activation and conversion, indoleamine 2,3-dioxygenase regulation of dendritic cells, vascular endothelial growth factor regulation of angiogenesis, fibrosis inhibition, endoglin, and Janus kinase signaling emerge as examples of important potential nexuses in the regulation of tumorigenesis and the tumor microenvironment that can be targeted. We have also identified therapeutic agents as approaches, in particular natural products such as berberine, resveratrol, onionin A, epigallocatechin gallate, genistein, curcumin, naringenin, desoxyrhapontigenin, piperine, and zerumbone, that may warrant further investigation to target the tumor microenvironment for the treatment and/or prevention of cancer.

Advances and perspectives of colorectal cancer stem cell vaccine

Colorectal cancer is essentially an environmental and genetic disease featured by uncontrolled cell growth and the capability to invade other parts of the body by forming metastases, which inconvertibly cause great damage to tissues and organs. It has become one of the leading causes of cancer-related mortality in the developed countries such as United States, and approximately 1.2 million new cases are yearly diagnosed worldwide, with the death rate of more than 600,000 annually and incidence rates are increasing in most developing countries. Apart from the generally accepted theory that pathogenesis of colorectal cancer consists of genetic mutation of a certain target cell and diversifications in tumor microenvironment, the colorectal cancer stem cells (CCSCs) theory makes a different explanation, stating that among millions of colon cancer cells there is a specific and scanty cellular population which possess the capability of self-renewal, differentiation and strong oncogenicity, and is tightly responsible for drug resistance and tumor metastasis. Based on these characteristics, CCSCs are becoming a novel target cells both in the clinical and the basic studies, especially the study of CCSCs vaccines due to induced efficient immune response against CCSCs. This review provides an overview of CCSCs and preparation technics and targeting factors related to CCSCs vaccines in detail.

Prognostic role of the neutrophil-to-lymphocyte ratio in pancreatic cancer: a meta-analysis

The relationship between the neutrophil-to-lymphocyte ratio (NLR) and tumours as a prognostic factor has been reported in many studies. In this meta-analysis, we evaluated the prognostic role of the NLR in pancreatic cancer (PC). A systematic search was performed in PubMed and Embase for relevant studies. Data from and characteristics of each study were extracted. A meta-analysis was performed to analyse the prognostic role of the NLR using the hazard ratio (HR) and 95% confidence intervals (95% CI). As a result, a total of 2035 patients in 9 cohorts were included in this meta-analysis. The pooled HR of 1.587 (95% CI: 1.411-1.785, p < 0.01) showed that patients with an elevated NLR were expected to have shorter overall survival (OS) after treatment. This meta-analysis suggests that an elevated NLR can be used as a predictor of survival in patients with pancreatic cancer.

Natural humoral immune response to ribosomal P0 protein in colorectal cancer patients

Background

Tumor associated antigens are useful in colorectal cancer (CRC) management. The ribosomal P proteins (P0, P1, P2) play an important role in protein synthesis and tumor formation. The immunogenicity of the ribosomal P0 protein in head and neck, in breast and prostate cancer patients and the overexpression of the carboxyl-terminal P0 epitope (C-22 P0) in some tumors were reported.

Methods

Sera from 72 colorectal tumor patients (67 malignant and 5 benign tumors) were compared with 73 healthy donor sera for the presence of antibodies to CEA, EGFR, ErbB2 and ribosomal P proteins by western blotting or ELISA. Expression of the C-22 P0 epitope on tissues and colon cancer cells was determined by immunoperoxidase staining and indirect immunofluorescence/western blotting, respectively, employing MAb 2B2. Biological effects of MAb 2B2 on colon cancer cells were assessed by the Sulforhodamine B cell proliferation assay, trypan blue exclusion test and cleaved caspase-3 detection. Fisher’s exact test was used to compare the number of auto-antibodies positive patients with healthy donors. Variation in the C-22 P0 expression, and in the number of apoptotic cells was evaluated by Student’s t-test. Variation in cell survival and cell death was evaluated by Newman-Keuls test.

Results

No significant humoral response was observed to CEA, EGFR and ErbB2 in CRC patients. Conversely, 7 out of 67 CRC patient sera reacted to ribosomal P proteins. The prevalence of P proteins auto-antibodies in CRC patients was significant. Five patients showed restricted P0 immunoreactivity, while two patients reacted simultaneously to all P proteins. The C-22 P0 epitope was homogenously expressed both in malignant tumors and the adjacent mucosa, but the intensity of expression was higher in the tumor. Starved colon cancer cells showed a higher C-22 P0 epitope plasma membrane expression compared to control cells. MAb 2B2 inhibited colon cancer cell growth and induced cell death in a dose dependent manner.

Conclusions

Our study shows a spontaneous humoral immune response to ribosomal P0 protein in CRC patients and the inhibition of in vitro cancer cell growth after C-22 P0 epitope targeting. The ribosomal P0 protein might be a useful immunological target in CRC patients.

Fas ligand DNA enhances a vaccination effect by coadministered DNA encoding a tumor antigen through augmenting production of antibody against the tumor antigen

Interaction of Fas and Fas ligand (FasL) plays an important role in the regulation of immune responses by inducing apoptosis of activated cells; however, a possible role of FasL in DNA vaccination has not been well understood. We examined whether administration of DNA encoding FasL gene enhanced antitumor effects in mice that were vaccinated with DNA expressing a putative tumor antigen gene, β-galactosidase (β-gal). Growth of β-gal-positive Colon 26 tumors was retarded in the syngeneic mice immunized with β-gal and FasL DNA compared with those vaccinated with β-gal or FasL DNA. We did not detect increased numbers of β-gal-specific CD8(+) T cells in lymph node of mice that received combination of β-gal and FasL DNA, but amounts of anti-β-gal antibody increased with the combination but not with β-gal or FasL DNA injection alone. Subtype analysis of anti-β-gal antibody produced by the combination of β-gal and FasL DNA or β-gal DNA injection showed that IgG2a amounts were greater in mice injected with both DNA than those with β-gal DNA alone, but IgG2b amounts were lower in both DNA-injected than β-gal DNA-injected mice. These data suggest that FasL is involved in boosting humoral immunity against a gene product encoded by coinjected DNA and enhances the vaccination effects.

Animal models of gastrointestinal and liver diseases. New mouse models for studying dietary prevention of colorectal cancer

Colorectal cancer is a heterogeneous disease that is one of the major causes of cancer death in the U.S. There is evidence that lifestyle factors like diet can modulate the course of this disease. Demonstrating the benefit and mechanism of action of dietary interventions against colon cancer will require studies in preclinical models. Many mouse models have been developed to study colon cancer but no single model can reflect all types of colon cancer in terms of molecular etiology. In addition, many models develop only low-grade cancers and are confounded by development of the disease outside of the colon. This review will discuss how mice can be used to model human colon cancer and it will describe a variety of new mouse models that develop colon-restricted cancer as well as more advanced phenotypes for studies of late-state disease.

Sorbitol induces apoptosis of human colorectal cancer cells via p38 MAPK signal transduction

Sorbitol has been reported to have anticancer effects in several tumor models, however its effects on colorectal cancer remain elusive. In the present study, the effects of sorbitol on growth inhibition and apoptosis in the colorectal cancer HCT116 cell line were evaluated and its mechanism of action was examined. An MTT assay was utilized to determine the effect of sorbitol on HCT116 cell proliferation at different time points and variable doses. Western blot analysis was used to examine the effect of sorbitol on apoptosis-related protein expression and the p38 MAPK signaling pathway. The results revealed that sorbitol may inhibit the growth of HCT116 cells in a time- and dose-dependent manner. Following treatment with sorbitol for 3 h, western blotting demonstrated cleavage of the caspase-3 zymogen protein and a cleavage product of poly (ADP-ribose) polymerase (PARP), a known substrate of caspase-3, was also evident. During sorbitol-induced apoptosis, the mitochondrial pathway was activated by a dose-dependent increase in Bax expression and cytochrome c release, while the expression of anti-apoptotic protein Bcl-2 was significantly decreased in a dose-dependent manner. The investigation for the downstream signal pathway revealed that sorbitol-induced apoptosis was mediated by an increase in phosphorylated p38 MAPK expression. Overall, the observations from the present study imply that sorbitol causes increased levels of Bax in response to p38 MAPK signaling, which results in the initiation of the mitochondrial death cascade. Therefore, sorbitol is a promising candidate as a potential chemotherapeutic agent for the treatment of colorectal cancer HCT116 cells.

Outcomes of colorectal cancer arising in solid organ transplant recipients

INTRODUCTION

The incidence of colorectal cancer posttransplantation is unclear. Limited reports exist and have conflicting conclusions. We aimed to review the clinical features and oncologic outcomes of colorectal cancer in transplant recipients at our institution.

METHODS

A retrospective review of all patients diagnosed with colorectal cancer after solid organ transplantation between 2000 and 2011 was conducted. Clinical features and outcomes were reviewed.

RESULTS

Twenty of 3,946 patients were identified. The most common single organ transplanted was the kidney (n = 8). Six patients had multiorgan transplantation. Median age of diagnosis of cancer was 64.3 years, and median time from transplant to diagnosis of cancer was 8.7 years. Ten patients were symptomatic at presentation. Cancer was identified on routine colonoscopy in seven patients. Tumors were most commonly found in the right colon (n = 14, 70%). Six patients had stage IV disease at presentation. Short-term morbidity was identified in 11 patients. Postoperative mortality occurred in one patient. Median follow-up was 2.47 years. Overall survival at 5 years was 69%, and disease-free survival was 68 %. Distant recurrence was seen in 3 (15%) patients.

CONCLUSION

Colorectal cancer in these patients is rare, and surgery can be done safely. Vigilant screening must be maintained in this patient population.

Prognostic role of neutrophil-to-lymphocyte ratio in colorectal cancer: a systematic review and meta-analysis

The prognostic role of inflammation index like neutrophil-to-lymphocyte ratio (NLR) in colorectal cancer (CRC) remains controversial. We conduct a meta-analysis to determine the predictable value of NLR in the clinical outcome of CRC patients. The analysis was carried out based on the data from 16 studies (19 cohorts) to evaluate the association between NLR and overall survival (OS) and progression-free survival (PFS) in patients with CRC. In addition, the relationship between NLR and clinicopathological parameters was assessed. Hazard ratio (HR) or odds ratio (OR) with its 95% confidence interval (CI) was used as the effect size estimate. Our analysis results indicated that elevated pretreatment NLR predicted poorer OS (HR: 1.813, 95% CI: 1.499-2.193) and PFS (HR: 2.102, 95% CI: 1.554-2.843) in patients with CRC. Increased NLR is also significantly associated with the poorer differentiation of the tumor (OR: 1.574, 95% CI: 1.226-2.022) and higher carcino-embryonie antigen (CEA) level (OR: 1.493, 95% CI: 1.308-1.705). By these results, we conclude that NLR gains a prognostic value for patients with CRC. NLR should be monitored in CRC patients for rational stratification of the patients and adjusting the treatment strategy.

Pretreatment neutrophil/lymphocyte ratio as a prognostic aid in colorectal cancer

BACKGROUND

Colorectal cancers(CRC) are the third most common cancer in the western world, with surgery preferred for management of non-metastatic disease and post surgical treatment usually arranged according to the TNM staging system. However, there is still prognostic variation between patients who have the same stage. It is increasingly recognized that variations within disease course and clinical outcome in colorectal cancer patients are influenced by not only oncological characteristics of the tumor itself but also host response factors. Recent studies have shown correlation between the inflammatory response and clinical outcomes in various cancers. The neutrophil/lymphocyte ratio (NLR) has been described as a marker for immune response to various stimuli including cancer.

MATERIAL-METHODS

Two hundred eighty-one CRC patients were included in our retrospective analysis, separated into two groups according to a cut-off value for the NLR. Patient data including age, gender, vertical penetration, anatomic location, and differentiation of the tumor, TNM stage, survival rate, and disease-free survival were analyzed for correlations with the NLR.

RESULTS

Using ROC curve analysis, we determined a cut-off value of 2.2 for NLR to be best to discriminate between patient survival in the whole group. In univariate analysis, high pretreatment NLR (p=0.001, 95%CI 1.483-4.846), pathologic nodal stage (p<0.001, 95%CI 1.082- 3.289) and advanced pathologic TNM stage (p<0.001, 95%CI 1.462-4.213) were predictive of shorter survival. In multivariate analysis, advanced pathologic TNM stage (p=0.001, 95%CI 1.303-26.542) and high pretreatment NLR (p=0.005, 95%CI 1.713-6.378) remained independently associated with poor survival.

CONCLUSIONS

High pre-treatment NLR is a significant independent predictor of shorter survival in patients with colorectal cancer. This parameter is a simple, easily accessible laboratory value for identifying patients with poorer prognosis.

Clinical Implications of Co-Inhibitory Molecule Expression in the Tumor Microenvironment for DC Vaccination: A Game of Stop and Go

The aim of therapeutic dendritic cell (DC) vaccines in cancer immunotherapy is to activate cytotoxic T cells to recognize and attack the tumor. T cell activation requires the interaction of the T cell receptor with a cognate major-histocompatibility complex-peptide complex. Although initiated by antigen engagement, it is the complex balance between co-stimulatory and co-inhibitory signals on DCs that results in T cell activation or tolerance. Even when already activated, tumor-specific T cells can be neutralized by the expression of co-inhibitory molecules on tumor cells. These and other immunosuppressive cues in the tumor microenvironment are major factors currently hampering the application of DC vaccination. In this review, we discuss recent data regarding the essential and complex role of co-inhibitory molecules in regulating the immune response within the tumor microenvironment. In particular, possible therapeutic intervention strategies aimed at reversing or neutralizing suppressive networks within the tumor microenvironment will be emphasized. Importantly, blocking co-inhibitory molecule signaling, often referred to as immune checkpoint blockade, does not necessarily lead to an effective activation of tumor-specific T cells. Therefore, combination of checkpoint blockade with other immune potentiating therapeutic strategies, such as DC vaccination, might serve as a synergistic combination, capable of reversing effector T cells immunosuppression while at the same time increasing the efficacy of T cell-mediated immunotherapies. This will ultimately result in long-term anti-tumor immunity.

Prognostic impact of tumour-infiltrating immune cells on biliary tract cancer

BACKGROUND

Biliary tract cancers (BTC) are relatively rare malignant tumours with poor prognosis. It is known from other solid neoplasms that antitumour inflammatory response has an impact on tumour behaviour and patient outcome. The aim of this study was to provide a comprehensive characterisation of antitumour inflammatory response in human BTC.

METHODS

Tumour-infiltrating T lymphocytes (CD4+, CD8+, and Foxp3+), natural killer cells (perforin+), B lymphocytes (CD20+), macrophages (CD68+) as well as mast cells (CD117+) were assessed by immunohistochemistry in 375 BTC including extrahepatic (ECC; n=157), intrahepatic (ICC; n=149), and gallbladder (GBAC; n=69) adenocarcinomas. Overall and intraepithelial quantity of tumour-infiltrating immune cells was analysed. Data were correlated with clinicopathological variables and patient survival.

RESULTS

The most prevalent inflammatory cell type in BTC was the T lymphocyte. Components of the adaptive immune response decreased, whereas innate immune response components increased significantly in the biliary intraepithelial neoplasia - primary carcinoma - metastasis sequence. BTC patients with intraepithelial tumour-infiltrating CD4+, CD8+, and Foxp3+ T lymphocytes showed a significantly longer overall survival. Number of total intraepithelial tumour-infiltrating Foxp3+ regulatory T lymphocytes (HR: 0.492, P=0.002) and CD4+ T lymphocytes (HR: 0.595, P=0.008) were tumour grade- and UICC-stage-independent prognosticators. The subtype-specific evaluation revealed that the tumour-infiltrating lymphocytic infiltrate is a positive outcome predictor in ECC and GBAC but not in ICC.

CONCLUSION

Our findings characterise the immune response in cholangiocarcinogenesis and identify inflammatory cell types that influence the outcome of BTC patients. Further, we show that BTC subtypes show relevant differences with respect to density, quality of inflammation, and impact on patient survival.

The in vivo immunomodulatory and synergistic anti-tumor activity of thymosin α1-thymopentin fusion peptide and its binding to TLR2

In the present study, the immunomodulatory and synergistic anti-tumor activity of thymosin α1-thymopentin fusion peptide (Tα1-TP5) was investigated in vivo. In addition, the potential receptor of Tα1-TP5 was investigated by surface plasmon resonance (SPR) binding studies. It was found that Tα1-TP5 (305 μg/kg) alleviated immunosuppression induced by hydrocortisone (HC). Tα1-TP5 (305 μg/kg) combined with cyclophosphamide (CY) had a better tumor growth inhibitory effect than CY alone. Furthermore, Tα1-TP5 had a higher affinity (KD=6.84 μmol/L) to toll-like receptor 2 (TLR2) than Tα1 (K(D)=35.4 μmol/L), but its affinity was not significantly different from that of TP5. The results of our present work indicate that Tα1-TP5 can possibly be developed as a new immunomodulatory agent.

Graphite Web: Web tool for gene set analysis exploiting pathway topology

Graphite web is a novel web tool for pathway analyses and network visualization for gene expression data of both microarray and RNA-seq experiments. Several pathway analyses have been proposed either in the univariate or in the global and multivariate context to tackle the complexity and the interpretation of expression results. These methods can be further divided into ‘topological’ and ‘non-topological’ methods according to their ability to gain power from pathway topology. Biological pathways are, in fact, not only gene lists but can be represented through a network where genes and connections are, respectively, nodes and edges. To this day, the most used approaches are non-topological and univariate although they miss the relationship among genes. On the contrary, topological and multivariate approaches are more powerful, but difficult to be used by researchers without bioinformatic skills. Here we present Graphite web, the first public web server for pathway analysis on gene expression data that combines topological and multivariate pathway analyses with an efficient system of interactive network visualizations for easy results interpretation. Specifically, Graphite web implements five different gene set analyses on three model organisms and two pathway databases. Graphite Web is freely available at http://graphiteweb.bio.unipd.it/.

Cliques for the identification of gene signatures for colorectal cancer across population

Background

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers worldwide. Studies have correlated risk of CRC development with dietary habits and environmental conditions. Gene signatures for any disease can identify the key biological processes, which is especially useful in studying cancer development. Such processes can be used to evaluate potential drug targets. Though recognition of CRC gene-signatures across populations is crucial to better understanding potential novel treatment options for CRC, it remains a challenging task.

Results

We developed a topological and biological feature-based network approach for identifying the gene signatures across populations. In this work, we propose a novel approach of using cliques to understand the variability within population. Cliques are more conserved and co-expressed, therefore allowing identification and comparison of cliques across a population which can help researchers study gene variations. Our study was based on four publicly available expression datasets belonging to four different populations across the world. We identified cliques of various sizes (0 to 7) across the four population networks. Cliques of size seven were further analyzed across populations for their commonality and uniqueness. Forty-nine common cliques of size seven were identified. These cliques were further analyzed based on their connectivity profiles. We found associations between the cliques and their connectivity profiles across networks. With these clique connectivity profiles (CCPs), we were able to identify the divergence among the populations, important biological processes (cell cycle, signal transduction, and cell differentiation), and related gene pathways. Therefore the genes identified in these cliques and their connectivity profiles can be defined as the gene-signatures across populations. In this work we demonstrate the power and effectiveness of cliques to study CRC across populations.

Conclusions

We developed a new approach where cliques and their connectivity profiles helped elucidate the variation and similarity in CRC gene profiles across four populations with unique dietary habits.

Absence of CD4 T-cell help provides a robust CD8 T-cell response while inducing effective memory in a preclinical model of melanoma

Immunotherapy strategies for cancer are focused on inducing effective and specific cytotoxic responses mediated by CD8 T cells. On the other hand, immunosuppressive mechanisms induced by the tumor, such as the generation of tumor-specific CD4(+)CD25(+)FoxP3(+) Tregs, conspire against the efficacy of immunotherapies. It has been considered that, similar to what has been observed in the context of immunological responses towards microbes, CD4 help is indispensable for the development of a successful and long-lasting (memory) CD8 immune response. In the recent article, Côté et al. reported that, in a mouse model of melanoma, total ablation of CD4 help does not hamper the development of a specific antitumor memory CD8 response. In addition, ablation of CD4 was more successful than strategies to deplete CD25 Tregs in generating memory CD8 T cells. These data opens the door for therapies destined to induce effective antitumor immune responses by ablation of whole CD4 T-cell populations.

Can neutrophil-to-lymphocyte ratio predict the survival of colorectal cancer patients who have received curative surgery electively?

PURPOSE

We evaluated the effect of neutrophil-to-lymphocyte ratio (NLR) on disease-free survival in patients with stages I to III colorectal cancer (CRC).

METHODS

There were 3857 patients identified from our database. We used receiver operating characteristic (ROC) analysis to identify the best cutoff value of NLR. A 5-year disease-free survival was used as end point. Survival analysis was used to assess the NLR effect, after stratification by several clinopathologic factors.

RESULTS

In the ROC analysis, NLR = 3 had the highest sensitivity and specificity. Elevated NLR (>3) in colon cancer seemed to accompany larger tumor size (~5 cm) and more advanced T stage. By multivariate analysis, elevated NLR in colon cancer was associated with an increased risk of disease progression or cancer death [hazard ratio (HR) 1.377, 95  % confidence interval 1.104-1.717, P = 0.014]. However, elevated NLR in rectal cancer lost its significance in multivariate analysis (HR 1.121, 95  % confidence interval 0.941-1.336, P = 0.200). Patients with elevated NLR had worse outcome, especially for colon cancer.

CONCLUSIONS

Preoperative NLR influenced the disease-free survival in patients with stages I to III CRC. Elevated NLR (>3) was associated with worse outcome (5-year disease-free survival 66.3  % vs. 78.9  % in colon cancer, P < 0.001; 60. 5 % vs. 66.2  % in rectal cancer, P = 0.008). The difference was larger in colon cancer than in rectal cancer. NLR should be considered as a prognostic factor for stages I to III CRC patients after curative surgery.

Dendritic cells the tumor microenvironment and the challenges for an effective antitumor vaccination

Many clinical trials have been carried out or are in progress to assess the therapeutic potential of dendritic-cell- (DC-) based vaccines on cancer patients, and recently the first DC-based vaccine for human cancer was approved by the FDA. Herewith, we describe the general characteristics of DCs and different strategies to generate effective antitumor DC vaccines. In recent years, the relevance of the tumor microenvironment in the progression of cancer has been highlighted. It has been shown that the tumor microenvironment is capable of inactivating various components of the immune system responsible for tumor clearance. In particular, the effect of the tumor microenvironment on antigen-presenting cells, such as DCs, does not only render these immune cells unable to induce specific immune responses, but also turns them into promoters of tumor growth. We also describe strategies likely to increase the efficacy of DC vaccines by reprogramming the immunosuppressive nature of the tumor microenvironment.

Prognostic significance of T cell subsets in peripheral blood of B cell non-Hodgkin's lymphoma patients

The role of tumor-infiltrating T cell subsets in the prognosis of non-Hodgkin's lymphoma (NHL) has previously been reported. In the present study, we investigated the prognostic significance of different T cell subsets in the peripheral blood of NHL patients. Immunophenotyping was performed on the peripheral blood samples of 45 patients with newly diagnosed B cell NHL using flow cytometry. The relationship between T cell subsets of CD4+, CD8+, CD3+CD25+, CD4+CD25+, CD4+CD25high [as T regulatory cells (T reg)], and the CD4/CD8 ratio with international prognostic index (IPI) and response to therapy was determined. The percentages of CD3+, CD4+, and CD8+ T cells in the peripheral blood of the patients were 49.1±20.3%, 23.6±11%, and 31.4±14.4%, respectively (CD4/CD8 ratio: 0.92±0.6). There were 4.2±3.2% T reg cells. A study of the percentage of T cells in relation to IPI score showed a higher proportion of CD3+CD25+, CD4+, and CD4+CD25+ cells in low-risk patients compared with intermediate/high risk groups (p<0.05). The above cells, as well as CD4+CD25high T reg cells, indicated a positive correlation with complete remission (CR) and survival. CD4 positivity correlated significantly with survival and CR durations, which were longer in patients with ≥20% CD4+ cells than those with <20% CD4+ cells, thus indicating the prognostic value of CD4+ T cells in NHL patients. There was no significant data on CD8+ cells as well as the CD4/CD8 ratio between distinct IPI groups and response to therapy. These data indicated the importance of CD4+ cells and the activation status of T cells in immunity against lymphoma and the prognostic implication of enumeration of these cells in NHL patients.

Microsatellite instability, EMAST, and morphology associations with T cell infiltration in colorectal neoplasia

BACKGROUND AND OBJECTIVES

Colorectal tumors are often observed with tumor infiltrating lymphocytes, presumably as a host-immune response, and patterns may segregate by types of genomic instability. Microsatellite unstable (MSI) colorectal cancers contain a pronounced lymphocyte reaction that can pathologically identify these tumors. Colorectal tumors with elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) have not been examined for lymphocyte patterns.

METHODS

We evaluated a 108-person cohort with 24 adenomas and 84 colorectal cancers for MSI and EMAST. Immunohistochemical detection of CD4+ and CD8+ T cell infiltration were performed. Prognostic relevance was assessed by survival analysis.

RESULTS

CD8+ T cell infiltration in the tumor cell nest (p = 0.013) and tumor stroma (p = 0.004) were more prominent in moderately and poorly differentiated adenocarcinoma than in adenoma and well-differentiated adenocarcinoma. CD8+ T cells in the tumor cell nest (p = 0.002) and tumor stroma (p = 0.009) were at higher density in tumors with ulcerating features compared to tumors with a sessile or polypoid appearance. MSI-H tumors showed a higher density of CD8+ T cell infiltrations in tumor cell nests (p = 0.003) and tumor stroma (p = 0.001). EMAST-positive tumors showed a higher density of CD8+ T cell infiltrations than EMAST-negative tumors both in tumor cell nest (p = 0.027) and in tumor stroma (p = 0.003). These changes were not observed with CD4+ T lymphocytes. There was no difference in cancer patient survival based on density of CD8+ cells.

CONCLUSIONS

CD8+ T lymphocytes, but not CD4+ cells, were increased in tumor cell nests and the tumor stroma in both MSI and EMAST tumors, and showed higher infiltration in ulcerated tumors. CD8+ T lymphocyte infiltration is associated with both EMAST and MSI patterns, and increases with histological advancement.

Clinicopathological significance of indoleamine 2,3-dioxygenase 1 expression in colorectal cancer

BACKGROUND

Indoleamine 2,3-dioxygenase 1 (IDO1) is a tryptophan-catabolising enzyme that induces immune tolerance by modulating T-cell responses. Carcinomas may create an immunosuppressive state via IDO1 expression. Here we examined a possible contribution of IDO1 on this phenomenon and investigated whether IDO1 has prognostic value in colorectal cancer (CRC).

METHODS

IDO1 expression was investigated by quantitative PCR and western blotting in three colon cancer cell lines, in basal state and after interferon (IFN)-γ stimulation. Semi-quantitative immunohistochemistry was used to evaluate IDO1 expression in 265 pT1-4N0-2Mx-staged CRCs. Results were related to clinical variables and correlated with amounts of CD3(+) and CD8(+) T lymphocytes, which were quantitatively evaluated using image analysis.

RESULTS

In vitro expression of IDO1 depended on IFN-γ stimulation. Higher IDO1 expression at the tumour invasion front was an independent adverse prognostic factor in pT1-4N1Mx-staged CRC. It was associated with overall survival (P=0.001) and with metachronous metastases (P=0.018). IDO1 expression was not associated with the presence of CD3(+) or CD8(+) T lymphocytes.

CONCLUSION

Higher IDO1 expression at the tumour invasion front is involved in CRC progression and correlates with impaired clinical outcome, suggesting that IDO1 is an independent prognostic indicator for CRC.