Tumor-infiltrating lymphocytes and perforation in colon cancer predict positive response to 5-fluorouracil chemotherapy

Survival outcomes in locally advanced dMMR rectal cancer: surgery plus adjunctive treatment vs. surgery alone

BACKGROUND

Recent studies have shown that deficient mismatch repair (dMMR) rectal cancer may be related to treatment resistance, resulting in a worse prognosis than proficient MMR (pMMR) rectal cancer. The purpose of this study was to explore whether surgery plus other treatments (radiotherapy and chemotherapy) can bring more benefits to these patients than surgery alone.

METHODS

A retrospective study of 168 patients with rectal adenocarcinoma who underwent total mesorectal excision was conducted using immunohistochemical methods to determine MMR status and a propensity score matching model to minimize potential confounding factors between subgroups of patients with different treatment regimens. Kaplan-Meier analysis, log-rank tests, and Cox regression models were used to assess overall survival (OS) and disease-free survival (DFS) in patient subgroups.

RESULTS

Only 6.9% (n = 168) of patients in the total cohort had dMMR rectal adenocarcinoma, and the most common cause of dMMR was a PMS2 deletion (103, 61.3%). The median DFS of the surgery alone group was 45.7 months (IQR, 40.9 to 77.8), and the median DFS of the surgery plus other treatment group was 43.9 months (IQR, 14.2 to 80.1). The surgery alone group was superior to the surgery plus other treatment group (HR, 0.16; 95% CI, 0.07 to 0.38; p = 0.005). There was no significant difference in OS (45.8 (IQR, 41.0 to 79.8) vs. 45.9 (IQR, 38.5 to 80.3)) between the two groups (HR, 0.57; 95% CI, 0.23 to 1.40; p = 0.263).

CONCLUSIONS

For patients with locally advanced dMMR rectal adenocarcinoma, compared with surgery alone, surgery plus other treatment options (radiotherapy and chemotherapy) do not grant long-term survival benefits but rather shorten DFS.

The immune modifying effects of chemotherapy and advances in chemo-immunotherapy

Immune checkpoint inhibitors (ICIs) have transformed the treatment paradigm for several malignancies. While the use of single-agent or combined ICIs has achieved acceptable disease control rates in a variety of solid tumors, such approaches have yet to show substantial therapeutic efficacy in select difficult-to-treat cancer types. Recently, select chemotherapy regimens are emerging as extensive modifiers of the tumor microenvironment, leading to the reprogramming of local immune responses. Accordingly, data is now emerging to suggest that certain anti-neoplastic agents modulate various immune cell processes, most notably the cross-presentation of tumor antigens, leukocyte trafficking, and cytokine biosynthesis. As such, the combination of ICIs and cytotoxic chemotherapy are beginning to show promise in many cancers that have long been considered poorly responsive to ICI-based immunotherapy. Here, we discuss past and present attempts to advance chemo-immunotherapy in these difficult-to-treat cancer histologies, mechanisms through which select chemotherapies modify tumor immunogenicity, as well as important considerations when designing such approaches to maximize efficacy and improve therapeutic response rates.

The Role of Tumor Microenvironment and Immune Response in Colorectal Cancer Development and Prognosis

Colorectal cancer (CRC) is one of the most common cancers worldwide. The patient’s prognosis largely depends on the tumor stage at diagnosis. The pathological TNM Classification of Malignant Tumors (pTNM) staging of surgically resected cancers represents the main prognostic factor and guidance for decision-making in CRC patients. However, this approach alone is insufficient as a prognostic predictor because clinical outcomes in patients at the same histological tumor stage can still differ. Recently, significant progress in the treatment of CRC has been made due to improvements in both chemotherapy and surgical management. Immunotherapy-based approaches are one of the most rapidly developing areas of tumor therapy. This review summarizes the current knowledge about the tumor microenvironment (TME), immune response and its interactions with CRC development, immunotherapy and prognosis.

Mucinous histology is associated with poor prognosis in locally advanced colorectal adenocarcinoma treated with postoperative first-line adjuvant chemotherapy: A systematic review and meta-analysis

PURPOSE

Postoperative adjuvant chemotherapy followed surgery is the standard management for localized advanced colorectal carcinoma (CRC). Mucinous adenocarcinoma (MAC) is a peculiar histological subtype of CRC, but the prognosis of MAC patients is controversial. The objective of this study is to assess the implication of MAC in survival of patients treated with surgery and firs-line adjuvant chemotherapy.

METHODS

Studies describing outcomes for advanced MAC and non-specific adenocarcinoma (AC) of CRC patients treated with first-line postoperative adjuvant chemotherapy followed surgery were searched in PubMed, Embase, Medline, EBSCO, Wiley, and Cochrane Library (January 1963-August 2021). Hazard ratios (HRs) of overall survival (OS), disease-free survival (DFS) and cancer-specific survival (CSS) for MAC to AC were extracted. Random-effects model was used for calculating the pooled HRs and 95% confidence interval (CI).

RESULTS

This meta-analysis is comprised of 8 studies involving a total of 124,303 CRC patients treated with first-line adjuvant chemotherapy followed surgery. The pooled HR for MAC was 1.23 (95% CI, 1.07-1.41, p < 0.01, I² = 80%), and the DFS (HR, 2.95, 95% CI, 1.22-7.14) of MAC patients were significantly poorer than AC patients. Similar results were also observed in stage III and FOLFOX regimen subgroups.

CONCLUSION

MAC was a risk factor for prognosis of localized advanced CRC patients treated with postoperative first-line adjuvant chemotherapy. Thus, the role of first-line adjuvant chemotherapy regimens should be further studied in these MAC patients.

Mismatch repair system deficiency is associated with chemoradiotherapy resistance in locally advanced rectal adenocarcinoma patients

BACKGROUND AND OBJECTIVES

Previous studies have concluded that colorectal cancer patients with deficient mismatch repair (dMMR) usually have a good prognosis. However, some studies have suggested that the prognosis of rectal cancer patients with dMMR appears to be worse. Our aim was to investigate chemoradiotherapy resistance in dMMR rectal tumors.

METHODS

A retrospective study of 217 patients with locally advanced rectal adenocarcinoma treated with chemoradiotherapy and total mesorectal excision surgery was conducted using immunohistochemistry to determine MMR status and propensity score matching models to reduce potential confounders. Kaplan-Meier analysis, log-rank test, and Cox regression models were used to assess overall survival (OS) and disease-free survival (DFS) in patient subgroups.

RESULTS

The 3-year DFS rates were 77.1% and 56.7% in the pMMR and dMMR groups, respectively. The pMMR group had significantly better DFS than the dMMR group (hazard ratio [HR], 2.07; 95% confidence interval [CI], 1.10-3.91; p = 0.019). However, there was no significant difference in OS between the two groups (45.7 [interquartile range, IQR], 39.3-72.1] vs. 47.5 [IQR, 29.5-72.1]) (HR, 1.39; 95% CI, 0.70-2.77; p = 0.35). Neither OS nor DFS was significantly different between the neoadjuvant chemoradiotherapy and postoperative chemoradiotherapy groups.

CONCLUSION

Locally advanced dMMR rectal adenocarcinoma exhibits greater chemoradiotherapy resistance than pMMR.

Antigen Presenting Cells from Tumor and Colon of Colorectal Cancer Patients Are Distinct in Activation and Functional Status, but Comparably Responsive to Activated T Cells

Although mouse models of CRC treatments have demonstrated robust immune activation, it remains unclear to what extent CRC patients' APCs and TILs interact to fuel or quench treatment-induced immune responses. Our ex vivo characterization of tumor and adjacent colon cell suspensions suggest that contrasting environments in these tissues promoted inversed expression of T cell co-stimulatory CD80, and co-inhibitory programmed death (PD)-ligand1 (PD-L1) on intratumoral vs. colonic APCs. While putative tumor-specific CD103+CD39+CD8+ TILs expressed lower CD69 (early activation marker) and higher PD-1 (extended activation/exhaustion marker) than colonic counterparts, the latter had instead higher CD69 and lower PD-1 levels. Functional comparisons showed that intratumoral APCs were inferior to colonic APCs regarding protein uptake and upregulation of CD80 and PD-L1 after protein degradation. Our attempt to model CRC treatment-induced T cell activation in vitro showed less interferon (IFN)-γ production by TILs than colonic T cells. In this model, we also measured APCs' CD80 and PD-L1 expression in response to activated co-residing T cells. These markers were comparable in the two tissues, despite higher IFN- γ exposure for colonic APCs. Thus, APCs within distinct intratumoral and colonic milieus showed different activation and functional status, but were similarly responsive to signals from induced T cell activation.

Role of Neutrophil to Lymphocyte Ratio and Platelet to Lymphocyte Ratio in Predicting the Response to First Line Chemotherapy in Colorectal Cancer Patients with Synchronous Liver Metastases: A Retrospective Study

Background: There is some evidence that showed that the high level of neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) is associated with poor survival in several malignancies including colorectal cancer (CRC); however data on the significance of these markers to predict response to systemic therapy is limited. Objectives: The aim of this study was to assess the role of pretreatment NLR and PLR in predicting response to first line chemotherapy in CRC patients with synchronous metastases. Methods: Clinical records of 81 CRC patients with synchronous liver metastases, who underwent upfront chemotherapy, were included in this retrospective study. The optimal cut of value for NLR and PLR was determined according to receiver operating characteristic (ROC) curve analysis. Correlation between response to chemotherapy and NLR or PLR was evaluated. Results: The optimal cut off for NLR and PLR was 2.666 and 182.589, respectively. Patients with low NLR had significantly higher objective response (complete response + partial response) compared to patients with high NLR (54.3% versus 13%, respectively, P: < 0.001). In patients with low PLR, 41.2% had objective response compared to 13.3% of patients with high PLR (P = 0.012). The univariate analysis determined that, both NLR and PLR are significantly associated with better objective response, but in multivariate analysis, only NLR was identified as an independent predictive marker of response [odds ratio = 4.55; P = 0.013]. Conclusions: Results of this study indicate that, measuring NLR might provide us an inexpensive method to predict response to first-line chemotherapy in CRC patients with synchronous liver metastases.

Stromal tumor-infiltrating lymphocytes level as a prognostic factor for resected intrahepatic cholangiocarcinoma and its prediction by apparent diffusion coefficient

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) are a prognostic factor or an indicator of chemotherapy response for various malignancies. The aim of this study was to investigate the prognostic impact of TILs in resected intrahepatic cholangiocarcinoma (IHCC). We also investigated the usefulness of the apparent diffusion coefficient (ADC) in diffusion-weighted magnetic resonance imaging (DW-MRI) to predict TILs.

METHODS

We enrolled 23 patients with IHCC who underwent initial hepatic resection in Tokushima University Hospital from 2006 to 2017. We evaluated stromal TILs in the tumor marginal area and central area in surgical specimens. Patients were divided into low vs high stromal TILs groups. We analyzed the patients' clinicopathological factors, including prognosis, according to the degree of stromal TILs. We also analyzed the correlation between stromal TILs and the minimum ADC value.

RESULTS

Stromal TILs in the marginal area reflected overall survival more accurately than that in the central area. Additionally, marginal low TILs was significantly associated with lymph node metastasis and portal vein invasion. Both overall- and disease-free survival rates in the marginal low TILs group were significantly worse than those in the marginal high TILs group (P < 0.05). In the multivariate analysis, marginal low TILs were an independent prognostic factor for both overall- and disease-free survival (P < 0.05), and marginal low TILs were significantly associated with lower minimum ADC values (P < 0.02).

CONCLUSIONS

Stromal TILs, especially in the marginal area, might demonstrate prognostic impact in patients with IHCC. Moreover, the ADC values from MRI may predict TILs in IHCC tumor tissue.

Cryopreservation of Whole Tumor Biopsies from Rectal Cancer Patients Enable Phenotypic and In Vitro Functional Evaluation of Tumor-Infiltrating T Cells

Simple Summary

Colorectal cancer (CRC) remains the third most common malignancy. Tumor-infiltrating lymphocytes (TILs) have emerged as correlates to CRC patient outcome after treatment. The pro- or anti-tumor responses of TILs are usually assessed in cell suspensions of fresh tumors that were surgically removed a few hours earlier. We propose a platform for concurrent enumeration and in vitro functional evaluation of TILs in cryopreserved tumor biopsies, offering the benefit of postponing tumor processing and analyses of TILs in cell suspensions until clinical post-treatment responses are established. Our platform is practical considering the inconsistent time when patient samples become available for research purposes and can be readily utilized by other laboratories. With a fresh portion of tumor biopsies as benchmark, we validated the recovery of viable TILs capable of interferon (IFN)-γ responses in the cryopreserved portion of same biopsies. Ultimately, this platform could provide sufficient information on TILs, to also predict patient outcome after CRC treatments.

Abstract

TILs comprise functionally distinct conventional and unconventional T cell subsets and their role in responses to CRC treatments is poorly understood. We explored recovery of viable TILs from cryopreserved tumor biopsies of (chemo)-radiated patients with rectal cancer to establish a platform for retrospective TIL analyses of frozen tumors from pre-selected study cohorts. Frequencies of TIL subsets and their capacity to mount IFN-γ responses in cell suspensions of fresh vs. cryopreserved portions of the same tumor biopsies were determined for platform validation. The percentages and proportions of CD4+ TILs and CD8+ cytotoxic T lymphocytes (CTLs) among total TILs were not affected by cryopreservation. While recovery of unconventional γδ T cells and mucosal-associated invariant T cells (MAIT cells) was stable after cryopreservation, the regulatory T cells (Tregs) were reduced, but in sufficient yields for quantification. IFN-γ production by in vitro-stimulated CD4+ TILs, CTLs, γδ T cells, and MAIT cells were proportionally similar in fresh and cryopreserved tumor portions, albeit the latter displayed lower levels. Thus, the proposed platform intended for TIL analyses on cryopreserved tumor biobank biopsies holds promises for studies linking the quantity and quality of TIL subsets with specific clinical outcome after CRC treatment.

Tumour immune microenvironment biomarkers predicting cytotoxic chemotherapy efficacy in colorectal cancer

The role of the local tumour and stromal immune landscape is increasingly recognised to be important in cancer development, progression and response to therapy. The composition, function, spatial orientation and gene expression profile of the infiltrate of the innate and adaptive immune system at the tumour and surrounding tissue has an established prognostic role in colorectal cancer (CRC). Multiple studies have confirmed that a tumour immune microenvironment (TIME) reflective of a type 1 adaptive immune response is associated with improved prognosis. There have been significant efforts to evolve these observations into validated, histopathology-based prognostic biomarkers, such as the Immunoscore. However, the clinical need lies much more in the development of predictive, not prognostic, biomarkers which have the potential to improve patient outcomes. This is particularly pertinent to help guide cytotoxic chemotherapy use in CRC, which remains the standard of care. Cytotoxic chemotherapy has recognised immunomodulatory activity distinct from its antimitotic effects, including mechanisms such as immunogenic cell death (ICD) and induction/inhibition of key immune players. Response to chemotherapy may differ with regard to molecular subtype of CRC, which are strongly associated with immune phenotypes. Thus, immune markers are potentially useful, though under-reported, predictive biomarkers. In this review, we discuss the impact of the TIME on response to cytotoxic chemotherapy in CRC, with a focus on baseline immune markers, and associated genomic and transcriptomic signatures.

Identification of MEG8/miR-378d/SOBP axis as a novel regulatory network and associated with immune infiltrates in ovarian carcinoma by integrated bioinformatics analysis

Background

To investigate the potential molecular mechanism of ovarian cancer (OC) evolution and immunological correlation using the integrated bioinformatics analysis.

Methods

Data from the Gene Expression Omnibus was used to gain differentially expressed genes (DEGs). Gene Ontology and Kyoto Encyclopedia of Gene and Genome pathway analysis were completed by utilizing the Database for Annotation, Visualization, and Integrated Discovery. After multiple validations via The Cancer Genome Atlas (TCGA), Genotype‐Tissue Expression (GTEx) projects, the Human Protein Atlas, Kaplan–Meier (KM) plotter, and immune logical relationships of the key gene SOBP were evaluated based on Tumor Immune Estimation Resource, and Gene Set Enrichment Analysis (GSEA) software. Finally, the lncRNAs‐miRNAs‐mRNAs subnetwork was predicted by starBase, TargetScan, miRBD, and LncBase, individually. Correlation of expression and prognosis for mRNAs, miRNAs, and lncRNAs were confirmed by TCGA, Gene Expression Profiling Interactive Analysis 2 (GEPIA 2), starBase, and KM.

Results

A total of 192 shared DEGs were discovered from the four data sets, including 125 upregulated and 67 downregulated genes. Functional enrichment analysis presented that they were mainly enriched in cartilage development, pathway in PI3 K‐Akt signaling pathway. Lower expression of SOBP was the independent prognostic factor for inferior prognosis in OC patients. The downregulation of SOBP enhanced the infiltration levels of B cells, CD8+ T cells, Macrophage, Neutrophil, and Dendritic cells. GSEA also disclosed low SOBP showed a significantly associated with the activation of various immune‐related pathways. Finally, we first reported that the MEG8/miR‐378d/SOBP axis was linked to the development and prognosis of OC through regulating the cytokines pathway.

Conclusions

Our study establishes a novel MEG8/miR‐378d/SOBP axis in the development and prognosis of OC, and the triple subnetwork probably affects the progression of the OC by regulating the cytokines pathway.

The local immunological microenvironment in colorectal cancer as a prognostic factor for treatment decisions in the clinic: The way ahead

Analysis of the local immunological microenvironment in colorectal cancer lesions yielded prognostic markers. Harnessing these insights for clinical application however requires the use of sophisticated technology and algorithms, especially the robust and reproducible quantification of immune cells. These technologies are available and will allow individualized treatment decisions beyond the current standard.

COL1A1 Is a Potential Prognostic Biomarker and Correlated with Immune Infiltration in Mesothelioma

Objective

Mesothelioma (MESO) is a rare tumor derived from mesothelium cells. The aim of this study was to explore key candidate genes and potential molecular mechanisms for mesothelioma through bioinformatics analysis.

Methods

The MESO expression profiles came from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. The differences in the infiltration levels of immune cells between MESO and normal tissues were assessed using CIBERSORT. Differentially expressed genes (DEGs) were identified by comprehensive analysis of multiple datasets. A protein-protein interaction (PPI) network was constructed, and a hub gene COL1A1 was selected for MESO. The expression and mutation of COL1A1 in MESO were analyzed in the cBioPortal database. The correlation between COL1A1 expression and immune cell infiltration was evaluated using the TIMER database. Gene Set Enrichment Analysis (GSEA) of COL1A1 was then performed. Finally, Kaplan-Meier survival analysis was presented to predict the survival times between high and low COL1A1 expression groups for MESO patients.

Results

There were distinct differences in the infiltration levels of immune cells between MESO and normal tissues. A total of 118 DEGs were identified by comprehensively analyzing three expression profile datasets. COL1A1, a hub gene, was identified to be highly expressed in MESO compared to normal tissues. COL1A1 genetic mutation occurred in 9% of MESO samples, and amplification was the most common type of mutation. COL1A1 expression was significantly correlated to the infiltration levels of CD4+ T cells, macrophages, and neutrophils. GSEA results indicated that COL1A1 could be involved in key biological processes and pathways like extracellular matrix and PI3K-Akt pathway. Patients with high COL1A1 expression usually experienced shorten overall survival time than those with its low expression.

Conclusion

Our findings revealed that COL1A1 could become a potential prognostic biomarker for MESO, which was significantly related to immune cell infiltration.

Prognostic and Predictive Cross-Roads of Microsatellite Instability and Immune Response to Colon Cancer

Understanding molecular features of colon cancer has shed light on its pathogenesis and progression. Over time, some of these features acquired clinical dignity and were incorporated in decision making. Namely, microsatellite instability (MSI) due to mismatch repair of defects, which primarily was adopted for the diagnosis of Lynch syndrome, became recognized as the biomarker of a different disease type, showing a less aggressive behavior. MSI tumors harbor high amounts of tumor infiltrating lymphocytes (TILs) due to their peculiar load in neoantigens. However, microsatellite stable colon cancer may also show high amounts of TILs, and this feature is as well associated with better outcomes. High TIL loads are in general associated with a favorable prognosis, especially in stage II colon cancer, and therein identifies a patient subset with the lowest probability of relapse. With respect to post-surgical adjuvant treatment, particularly in stage III, TILs predictive ability seems to weaken along with the progression of the disease, being less evident in high risk patients. Moving from cohort studies to the analysis of a series from clinical trials contributed to increase the robustness of TILs as a biomarker. The employment of high TIL densities as an indicator of good prognosis in early-stage colon cancers is strongly advisable, while in late-stage colon cancers the employment as an indicator of good responsiveness to post-surgical therapy requires refinement. It remains to be clarified whether TILs could help in identifying those patients with node-positive cancers to whom adjuvant treatment could be spared, at least in low-risk groups as defined by the TNM staging system.

Selective Photokilling of Colorectal Tumors by Near-Infrared Photoimmunotherapy with a GPA33-Targeted Single-Chain Antibody Variable Fragment Conjugate

Antibody-based near-infrared photoimmunotherapy (NIR-PIT) is an attractive strategy for cancer treatment. Tumor cells can be selectively and efficiently killed by the targeted delivery of an antibody-photoabsorber complex followed by exposure to NIR light. Glycoprotein A33 antigen (GPA33) is highly expressed in most human colorectal cancers (CRCs) and is an ideal diagnostic and therapeutic target. We previously produced a single-chain fragment of a variable antibody against GPA33 (A33scFv antibody). Here, we investigate the efficacy of NIR-PIT by combining A33scFv with the NIR photoabsorber IR700 (A33scFv-IR700). In vitro, recombinant A33scFv displayed specific binding and delivery of an NIR dye to GPA33-positive tumor cells. Furthermore, A33scFv-IR700-mediated NIR-PIT was successful in rapidly and specifically killing GPA33-positive colorectal tumor cells. NIR-PIT treatment induced the release of lactate dehydrogenase from tumor cells, followed by cell necrosis, rather than apoptosis, through the promotion of reactive oxygen species accumulation in tumor cells. In mice bearing LS174T tumor grafts, A33scFv selectively accumulated in GPA33-positive tumors. Following only a single injection of the conjugate and subsequent illumination, A33scFv-IR700-mediated NIR-PIT induced a significant increase in therapeutic response in LS174T-tumor mice compared with that in the non-NIR-PIT groups (p < 0.001). Because the GPA33 antigen is specifically expressed in CRC tumors, A33scFv-IR700 might be a promising antibody fragment-photoabsorber conjugate for NIR-PIT of CRC.

Artificial intelligence-guided tissue analysis combined with immune infiltrate assessment predicts stage III colon cancer outcomes in PETACC08 study

OBJECTIVE

Diagnostic tests, such as Immunoscore, predict prognosis in patients with colon cancer. However, additional prognostic markers could be detected on pathological slides using artificial intelligence tools.

DESIGN

We have developed a software to detect colon tumour, healthy mucosa, stroma and immune cells on CD3 and CD8 stained slides. The lymphocyte density and surface area were quantified automatically in the tumour core (TC) and invasive margin (IM). Using a LASSO algorithm, DGMate (DiGital tuMor pArameTErs), we detected digital parameters within the tumour cells related to patient outcomes.

RESULTS

Within the dataset of 1018 patients, we observed that a poorer relapse-free survival (RFS) was associated with high IM stromal area (HR 5.65; 95% CI 2.34 to 13.67; p<0.0001) and high DGMate (HR 2.72; 95% CI 1.92 to 3.85; p<0.001). Higher CD3+ TC, CD3+ IM and CD8+ TC densities were significantly associated with a longer RFS. Analysis of variance showed that CD3+ TC yielded a similar prognostic value to the classical CD3/CD8 Immunoscore (p=0.44). A combination of the IM stromal area, DGMate and CD3, designated 'DGMuneS', outperformed Immunoscore when used in estimating patients' prognosis (C-index=0.601 vs 0.578, p=0.04) and was independently associated with patient outcomes following Cox multivariate analysis. A predictive nomogram based on DGMuneS and clinical variables identified a group of patients with less than 10% relapse risk and another group with a 50% relapse risk.

CONCLUSION

These findings suggest that artificial intelligence can potentially improve patient care by assisting pathologists in better defining stage III colon cancer patients' prognosis.

Noninvasive imaging evaluation of tumor immune microenvironment to predict outcomes in gastric cancer

BACKGROUND

The tumor immune microenvironment can provide prognostic and predictive information. A previously validated ImmunoScore of Gastric Cancer (IS_GC) evaluates both lymphoid and myeloid cells in the tumor core and invasive margin with immunohistochemical staining of surgical specimens. We aimed to develop a noninvasive radiomics-based predictor of IS_GC.

PATIENTS AND METHODS

In this retrospective study including four independent cohorts of 1778 patients, we extracted 584 quantitative features from the intratumoral and peritumoral regions on contrast-enhanced computed tomography images. A radiomic signature [radiomics ImmunoScore (RIS)] was constructed to predict IS_GC using regularized logistic regression. We further evaluated its association with prognosis and chemotherapy response.

RESULTS

A 13-feature radiomic signature for IS_GC was developed and validated in three independent cohorts (area under the curve = 0.786, 0.745, and 0.766). The RIS signature was significantly associated with both disease-free and overall survival in the training and all validation cohorts [hazard ratio (HR) range: 0.296-0.487, all P < 0.001]. In multivariable analysis, the RIS remained an independent prognostic factor adjusting for clinicopathologic variables (adjusted HR range: 0.339-0.605, all P < 0.003). For stage II and stage III disease, patients with a high RIS derived survival benefit from adjuvant chemotherapy {HR = 0.436 [95% confidence interval (CI) 0.253-0.753], P = 0.002; HR = 0.591 (95% CI 0.428-0.818), P < 0.001, respectively}, whereas those with a low RIS did not.

CONCLUSION

The RIS is a reliable tool for evaluation of immunoscore and retains the prognostic significance in gastric cancer. Future prospective studies are required to confirm its potential to predict treatment response and select patients who will benefit from chemotherapy.

Identification of MMP1 as a Potential Prognostic Biomarker and Correlating with Immune Infiltrates in Cervical Squamous Cell Carcinoma

Cervical squamous cell carcinoma (CESC) is a human papillomavirus-driven tumor that the underlying molecular mechanisms are unclear. This study aimed to elucidate the key candidate genes and potential mechanism in CESC by bioinformatics analysis. A total of 132 common differentially expressed genes (DEGs) were identified based on three expression profile data sets. A multivariate Cox proportional regression model was used to develop a four-gene prognostic signature. Mechanistically, the correlationship between MMP1 and tumor-infiltrating lymphocytes was further analyzed. Furthermore, annotations were investigated by Gene Ontology (GO) and The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Finally, potential drugs for CESC treatment were predicted by Connectivity Map. We profiled four genes (EFNA1, ANLN, MMP1, and ZWINT) with significant prognostic values for CESC. Multiple public available data sets were used for mRNA expression and prognostic characterization. Subsequently, GO and KEGG pathway analyses showed DEGs were mainly enriched in cell cycle, immunity, and metabolic-related pathway. We then conducted an integrated analysis of MMP1, and the expression of MMP1 showed significantly inverse association with the amount of CD8+ T cells, CD4+ T cells, and macrophages infiltration. Our findings suggest the four-gene signature may be associated with prognosis. We further revealed that MMP1 may be a novel biomarker for immunotherapy, and prognostic judgment of patients with cervical cancer.

PD-1/PD-L1-dependent immune response in colorectal cancer

Colorectal cancer (CRC) is still considered as the third most frequent cancer in the world. Microsatellite instability (MSI), inflammation, and microRNAs have been demonstrated as the main contributing factors in CRC. Subtype 1 CRC is defined by NK cells infiltration, induction of Th1 lymphocyte and cytotoxic T cell responses as well as upregulation of immune checkpoint proteins including programmed cell death-1 (PD-1). Based on the diverse features of CRC, such as the stage and localization of the tumor, several treatment approaches are available. However, the efficiency of these treatments may be decreased due to the development of diverse resistance mechanisms. It has been proven that monoclonal antibodies (mAbs) can increase the effectiveness of CRC treatments. Nowadays, several mAbs including nivolumab and pembrolizumab have been approved for the treatment of CRC. Immune checkpoint receptors including PD-1 can be inhibited by these antibodies. Combination therapy gives an opportunity for advanced treatment for CRC patients. In this review, an update has been provided on the molecular mechanisms involved in MSI colorectal cancer immune microenvironment by focusing on PD-ligand 1 (PD-L1) and treatment of patients with advanced immunotherapy, which were examined in the different clinical trial phases. Considering induced expression of PD-L1 by conventional chemotherapeutics, we have summarized the role of PD-L1 in CRC, the chemotherapy effects on the PD-1/PD-L1 axis and novel combined approaches to enhance immunotherapy of CRC by focusing on PD-L1.

Tumor-infiltrating lymphocytes in primary tumors of colorectal cancer and their metastases

The presence of tumor cells in the large intestine stimulates hypoxia and local inflammatory mediators that activate numerous inflammatory cells, including a diverse lymphoid tumor cell population. The aim of the present study was to evaluate tumor-infiltrating lymphocytes (TILs) located in the invasive primary tumor, surrounding deposits of tumor cells and those present in distal metastatic cells in the liver of patients with colorectal cancer. Furthermore, the correlation of TILs with anatomical parameters was assessed. The study group included 123 patients with primary tumor colorectal cancer without distant metastasis, 25 cases with deposits of colorectal cancer cells and 15 cases of colorectal cancer liver metastasis. TILs were assessed in tissues stained with hematoxylin-eosin using light microscopy and evaluated by two independent pathologists blinded to the clinical information. Infiltration of TILs in the invasive front of primary tumor was stronger compared with those surrounding deposits of cancer cells and liver metastases (P<0.001). TILs in the invasive front of primary tumor masses were associated with various variables linked with tumor progression and inflammatory cell infiltrate. TILs distributed around the deposits of cancer cells were associated with postoperative treatment; however, those localized in the invasive front of liver metastases were correlated with preoperative therapy. In conclusion, TILs assessment in primary tumors of colorectal cancer, surrounding deposits of tumor cells and in the metastatic cells in the liver may be helpful in understanding the role of these cells in the organization of immune response.

Greater negative lymph node count predicts favorable survival of patients with breast cancer in the setting of neoadjuvant chemotherapy and mastectomy

Aim: Adequate lymph node evaluation is recommended in patients with malignant tumors. However, the role of negative lymph nodes (NLNs) remains unclear in breast cancer (BC), especially in patients who have received neoadjuvant chemotherapy and mastectomy. Materials & methods: A total of 435 patients were included in the analysis. On multivariate analysis, NLN count was an independent predictor of 5 year disease-free survival and 5 year overall survival. Results: Patients with NLN count <10 showed significantly worse 5 year disease-free survival than those with NLN count ≥10 (34.8 and 78.2%; p = 0.000); the corresponding 5 year overall survival rates were also significantly different (52.0 and 82.7%; p = 0.000). Conclusion: This is the first study that confirms the relationship between NLN count and prognosis of patients in the setting of neoadjuvant chemotherapy and mastectomy. More NLNs imply better prognosis.

Tumor-Infiltrating Immune Cells Act as a Marker for Prognosis in Colorectal Cancer

Tumor-infiltrating immune cells (TIICs) play essential roles in cancer development and progression. However, the association of TIICs with prognosis in colorectal cancer (CRC) patients remains elusive. Infiltration of TIICs was assessed using ssGSEA and CIBERSORT tools. The association of TIICs with prognosis was analyzed in 1,802 CRC data downloaded from the GEO (https://www.ncbi.nlm.nih.gov/geo/) and TCGA (https://portal.gdc.cancer.gov/) databases. Three populations of TIICs, including CD66b+ tumor-associated neutrophils (TANs), FoxP3+ Tregs, and CD163+ tumor-associated macrophages (TAMs) were selected for immunohistochemistry (IHC) validation analysis in 1,008 CRC biopsies, and their influence on clinical features and prognosis of CRC patients was analyzed. Prognostic models were constructed based on the training cohort (359 patients). The models were further tested and verified in testing (249 patients) and validation cohorts (400 patients). Based on ssGSEA and CIBERSORT analysis, the correlation between TIICs and CRC prognosis was inconsistent in different datasets. Moreover, the results with disease-free survival (DFS) and overall survival (OS) data in the same dataset also differed. The high abundance of TIICs found by ssGSEA or CIBERSORT tools can be used for prognostic evaluation effectively. IHC results showed that TANs, Tregs, TAMs were significantly correlated with prognosis in CRC patients and were independent prognostic factors (P_DFS ≤ 0.001; P_OS ≤ 0.023). The prognostic predictive models were constructed based on the numbers of TANs, Tregs, TAMs (C-index_DFS&OS = 0.86; AIC_DFS = 448.43; AIC_OS = 184.30) and they were more reliable than traditional indicators for evaluating prognosis in CRC patients. Besides, TIICs may affect the response to chemotherapy. In conclusion, TIICs were correlated with clinical features and prognosis in patients with CRC and thus can be used as markers.

Effect of lymph nodes count in node-positive gastric cancer

Background: The retrieved lymph node (LN) count has been confirmed as a prognostic indicator in various cancers. However, the correlation between LN counts and patient prognosis in gastric cancer with node-positive is not fully studied.

Methods: A total of 8475 patients undergoing gastrectomy in Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer were analyzed. Kaplan-Meier methods and multivariable Cox regression models were used to analyze long-term outcomes and risk factors. Moreover, nomograms including LN counts were established to predict overall survival (OS) and cancer-specific survival (CSS), and Harrell's concordance index (c-index) was adopted to evaluate prediction accuracy.

Results: Patients were stratified into 1-6, 7-14, and > 14 subgroups according to the optimal cutoff for retrieved LNs in terms of 5-year CSS. Further analysis indicated that higher LN counts were an independent predictor of longer survival in each N category. Nomograms on CSS and OS were established according to all significant factors, and c-indexes were 0.663 and 0.654 (P< 0.001), respectively.

Conclusions: These results indicated that the more the LNs retrieved, the better the survival would be. Nomograms incorporating LN counts can be recommended as practical models to provide more accurate prognostic information for GC patients.

De-escalating chemotherapy for stage II colon cancer?

BACKGROUND

Although adjuvant chemotherapy is recommended for patients with stage II colon cancer characterized by poor prognostic features, its pros and cons remain a controversial issue. We aim to evaluate the real effectiveness of chemotherapy on stage II colon cancer as well as select suitable patients.

METHODS

Patients during 1988-2013 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. The competing risk regression model and propensity score matching method were used to evaluate colon-cancer-specific death (CCSD) and non-CCSD. Also, a competing-risk nomogram was constructed to identify risk of patients. Risk score (RS) was calculated according to nomogram.

RESULTS

A total of 58,133 patients were included, 25.66% received chemotherapy, and 74.34% were without chemotherapy. In total, 19.95% and 25.78% of patients died of CCSD and non-CCSD, respectively. Univariate and multivariate analyses showed that receiving chemotherapy appears to be associated with more CCSD and less non-CCSD (HR 1.23, 95% CI 1.18-1.28; HR 0.45, 95% CI 0.43-0.47, respectively), even after adjustment for covariates and propensity score weighting. A competing-risk nomogram was established; the model was relatively good with a C-index of 0.661. Based on the RS, risk stage could only predict prognosis but failed to predict the benefit from chemotherapy.

CONCLUSIONS

The value of chemotherapy is much less than we thought. It is time to de-escalate chemotherapy for stage II colon cancer. CCSD, rather than overall survival, should be considered as an appropriate primary end point for future trials in stage II colon cancer.

An immune infiltration signature to predict the overall survival of patients with colon cancer

Immune infiltration of tumors has been increasingly accepted as a prognostic factor in colon cancer. Here, we aim to develop a novel immune signature, based on estimated immune landscape from tumor transcriptomes, to predict the overall survival of patients with colon cancer. The compositions of 22 immune cell subtypes from three microarray datasets were characterized with the CIBERSORT deconvolution algorithm. A prognostic immunoscore (PIS) model for overall survival prediction was established by using least absolute shrinkage and selection operator (LASSO) penalized regression analysis. A total of 17 immune cell markers were screened out in the LASSO model and were then aggregated to generate the PIS. In the training cohort (n = 490), patients with high PIS exhibited a remarkably poorer overall survival than those with low PIS. Similar results were obtained in patients with different TNM stages and in patients receiving adjunctive chemotherapy or not. Multivariate Cox regression indicated that the PIS was an independent predictor for overall survival in colon cancer (hazard ratio: 2.734, 95% confidence interval: 2.052-3.643, p < .001). The prognostic capability of PIS was also confirmed in the testing cohort (n = 245) and the entire cohort (n = 735). As for biological implications, the PIS was significantly associated with some immune checkpoints, inflammatory factors, epithelial-mesenchymal transformation regulators, and many known signaling pathways in cancer. The results of our study provide a novel and promising immune signature for overall survival prediction of patients with colon cancer.

Intrinsic β-catenin signaling suppresses CD8+ T-cell infiltration in colorectal cancer

Colorectal cancer is the third most common cancer worldwide and shows resistance to immune checkpoint inhibitors which have been demonstrated to be effective in many other types of cancers. Pre-existing T-cell response in tumor microenvironment often determines the therapeutic benefit of immune checkpoint blockade. Tumor-infiltrating CD8⁺ T-cells are considered as the major effector immune cells in antitumor immunity. In this study, we aimed to identify the intrinsic oncogenic pathway that contributes to a reduction of CD8⁺ T-cell infiltration in colorectal cancer. To achieve this, human colon adenocarcinoma samples derived from The Cancer Genome Altas (TCGA) were stratified into low T-cell-inflamed and high T-cell-inflamed groups based on the expression of T-cell signature genes. Gene set enrichment analysis of revealed a close correlation between activation of the Wnt/β-catenin signaling pathway and absence of T-cell infiltration. By immunohistochemical analysis of 155 colorectal cancer tissues, we found that tumors with high β-catenin expression showed a significant reduction of CD8⁺ T-cell infiltration. Mechanistically, β-catenin can regulate CCL4 expression to recruit CD103⁺ dendritic cells to enable CD8⁺ T cell activation. Collectively, our data indicate that oncogenic β-catenin signal may mediate colorectal cancer resistance to immunotherapies, pointing to the combined PD-1-immunotherapy with targeting β-catenin in colorectal cancer.

Prognostic Implication of Negative Lymph Node Count in ypN+ Rectal Cancer after Neoadjuvant Chemoradiotherapy and Construction of a Prediction Nomogram

PURPOSE

This study aimed to investigate the prognostic significance of negative lymph nodes (NLNs) for ypN+ rectal cancer after neoadjuvant chemoradiotherapy (nCRT) and radical surgery and to construct a nomogram predicting disease-free survival (DFS).

METHOD

One hundred fifty-eight eligible patients were included. X-tile analysis was performed to determine cutoff values of NLNs. Clinicopathological and survival outcomes were compared. A Cox regression analysis was performed to identify prognostic factors of DFS. A nomogram was constructed and validated internally.

RESULTS

X-tile analysis identified cutoff values of 4 and 16 in terms of DFS (χ² = 8.129, p = 0.017). The 3-year DFS rates for low (≤ 4), middle (5-16), and high (≥ 17) NLNs group was 15.2, 55.5, and 73.1%, respectively (P = 0.017). NLN count (NLNs ≥ 17, HR = 0.400, P = 0.022), IMA nodal metastasis (HR = 1.944, P = 0.025), tumor differentiation (poor/anaplastic, HR = 1.805, P = 0.021), and ypT4 stage (HR = 7.787, P = 0.047) were independent prognostic factors of DFS. A predicting nomogram incorporating the four significant predictors was developed with a C-index of 0.64.

CONCLUSION

NLN count was an independent prognostic factor of DFS in patients with ypN+ rectal cancer following nCRT. A nomogram incorporating NLN count, IMA nodal metastasis, tumor differentiation, and ypT stage could stratify rectal cancer patients with different DFS and might be helpful during clinical decision-making.

Colorectal Cancer Biomarkers in the Era of Personalized Medicine

The 5-year survival probability for patients with metastatic colorectal cancer has not drastically changed over the last several years, nor has the backbone chemotherapy in first-line disease. Nevertheless, newer targeted therapies and immunotherapies have been approved primarily in the refractory setting, which appears to benefit a small proportion of patients. Until recently, rat sarcoma (RAS) mutations remained the only genomic biomarker to assist with therapy selection in metastatic colorectal cancer. Next generation sequencing has unveiled many more potentially powerful predictive genomic markers of therapy response. Importantly, there are also clinical and physiologic predictive or prognostic biomarkers, such as tumor sidedness. Variations in germline pharmacogenomic biomarkers have demonstrated usefulness in determining response or risk of toxicity, which can be critical in defining dose intensity. This review outlines such biomarkers and summarizes their clinical implications on the treatment of colorectal cancer. It is critical that clinicians understand which biomarkers are clinically validated for use in practice and how to act on such test results.

Negative Lymph Node Count and Lymph Node Ratio Are Associated With Survival in Male Breast Cancer

BACKGROUND

Male breast cancer (MBC) is usually diagnosed at late stages and therefore has a worse prognosis than female breast cancer (FBC). MBC is also more likely to have lymph node (LN) involvement than FBC.

MATERIALS AND METHODS

We sought to determine the prognostic role of the examined lymph node (LN), negative LN (NLN), and positive LN counts and the LN ratio (LNR), defined as (positive LNs/ENLs), on the survival rate among MBC patients. We performed a large population-based study using the data from the Surveillance, Epidemiology, and End Results program.

RESULTS

Older age, black race, stage IV disease, ≤ 1 NLN, and a > 31.3% LNR were significantly associated with worse survival across all prediction models. Moreover, we demonstrated a decreased risk of mortality in MBC patients across the MBC-specific survival model (hazard ratio, 0.98; 95% confidence interval, 0.96-0.998; P = .03) and 10-year MBC-specific survival model (hazard ratio, 0.98; 95% confidence interval, 0.96-0.999; P = .04).

CONCLUSION

MBC has had an augmented incidence over the years. We found several independent predictors of MBC survival, including age, race, stage, NLNs, and the LNR. We strongly suggest adding the NLN count and/or LNR into the current staging system. Further studies are needed to provide information on the mechanisms underlying the association between the NLN count and MBC survival and the LNR and MBC survival.

Combined intra-arterial and intravenous chemotherapy for unresectable, advanced gastric cancer has an improved curative effect compared with intravenous chemotherapy only

The aim of the present study was to evaluate the efficacy and safety of a combination of intra-arterial and intravenous chemotherapy in the treatment of unresectable, advanced gastric cancer, and assess which patients are likely to benefit from combined treatment. The clinical data of 128 patients diagnosed with unresectable, advanced gastric cancer at The Fourth Hospital of Hebei Medical University (Shijiazhuang, China) from January 2009 to September 2012 were retrospectively analyzed. The patients were divided into two groups as follows: Those who received regional intra-arterial chemoembolization plus systemic chemotherapy (combined group; n=62) and those who received systemic chemotherapy only (venous group; n=66). The clinical response, overall survival (OS) and toxic effects in the two groups were compared. Univariate and multivariate analyses were performed to identify the primary factors affecting the survival time of patients in the combined group. The overall response rate was significantly increased (35.5%) in the combined group compared with the venous group (19.7%; P=0.045). The median OS was 14 months in the combined group and 13 months in the venous group, and the 1-year and 2-year survival rates in the two groups were 45.2 and 9.7%, and 40.9 and 6.1%, respectively. There were significant differences between the survival curves (P=0.044). The median time to progression in the combined group and the venous group was 10 months and 6 months, respectively, and the difference was statistically significant (P=0.003). Multivariate analysis revealed that tumor-node-metastasis (TNM)-stage and the degree of tumor staining were independent factors affecting OS. No differences in adverse reactions between the two groups were observed (P>0.05). The combination of intra-arterial and intravenous chemotherapy may effectively improve the rate of clinical response, prolong OS and time to symptomatic progression in patients with unresectable, advanced gastric cancer, in particular those with an earlier TNM stage and distinct tumor staining.

Increasing negative lymph node count predicts favorable OS and DSS in breast cancer with different lymph node-positive subgroups

Adequate lymph node evaluation is recommended for optimal staging in patients with malignant neoplasms including breast cancer. However, the role of negative lymph nodes (LNs) remains unclear in breast cancer according to N substage (N1, N2, and N3). In this study, for the first time, we analyzed the prognostic significance of negative LNs in breast cancer patients. A critical relationship was observed between negative LN count and survival, independent of patient characteristics and other related molecular variables including estrogen receptor (PR) status, progesterone receptor (ER) status, human epidermal growth factor receptor 2 (HER2) status, depth of tumor invasion and degree of differentiation. This research is of great importance in providing more information about the prognosis of breast cancer by statistical analysis of negative lymph nodes and can serve as a useful supplement to the current pathological system.

Negative to positive lymph node ratio is a superior predictor than traditional lymph node status in stage III colorectal cancer

Negative lymph node counts has recently attracted attention as a prognostic indicator in colorectal cancer (CRC). But little is known about prognostic significance of negative to positive lymph node ratio (NPR) in CRC. Our aim was to determine impact of NPR on oncological outcomes in patients with stage III CRC. This retrospective study included 2,256 patients with stage III CRC under curative resection at Fudan university Shanghai cancer center. Kaplan-Meier methods and multivariable Cox regression models were built for the analysis of survival outcomes and risk factors. Accuracy of the NPR was assessed with the Harrell's concordance-index(C-index).X-tile program identified 2.38 or 0.55/2.38 as the optimal cutoff value for NPR to divide the cohort into high/low risk or high/middle/low risk subsets in terms of CRC cause specific survival (CCSS). In a multivariate analysis, NPR was significant independent prognostic factors for CCSS (P<0.05), notably, N classification was not an independently prognostic factor (P>0.05). Further analysis found NPR could give detailed prognostic classification for both N1 and N2 stage (P<0.05). Interestingly, patients in N2+ NPR >2.38 stage have similar survival outcome with N1+ NPR >2.38 stage (χ2=0.030, P=0.863), and better than those at N1+ NPR ≤2.38 and N2+ NPR ≤2.38 stage (P<0.001). The TN_NPRM stage was more accurate for predicting CCSS (C-index = 0.659) than current TNM stage system(C-index = 0.628) (P<0.001). Collectively, NPR was an independent prognostic factor for stage III CRC patients, it could provide more accurate prognostic information than the current node stage system.

The prognostic value of lymph nodes count on survival of patients with node-negative gastric cancer

The retrieved lymph node (LN) count has been validated as a prognostic factor in various cancers. However, the interaction between LN counts and patients' prognosis in gastric cancer with negative-LN metastasis is not fully studied. Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer patients were used for analysis in this study. Patients operated on for gastric cancer at N0 stage between 2004 and 2012 were identified from the SEER database. The association between the LN counts and survival was assessed using the Cox proportional hazards model. Patients were stratified into 1–4, 5−13, and > 13 subgroups according to LN count cut-off values determined by X-tile program, with the 5-year cause specific survival (CSS) rate of 64.8%, 72.5%, and 79.4%, respectively. LN count was also validated as an independently prognostic factor in multivariate Cox analysis (P < 0.001). In addition, nomograms including LN counts on CSS were established according to all significant factors, and the c-index was 0.703 (95% CI: 0.672−0.734). Further study indicated that patients with no LN metastasis had a decreased risk of death for each patient with LN examined up to approximately 14 LNs. Collectively, our study firmly demonstrated that the number of the retrieved LNs count was an independent prognostic factor for gastric cancer with no LN metastasis. The higher the LN count, the better the survival would be; the best CSS was observed on the LN count more than 14.

Increased number of negative lymph nodes is associated with improved survival outcome in node positive gastric cancer following radical gastrectomy

The concept of negative lymph node (NLN) counts has recently attracted attention as a prognostic indicator in various cancer. However, the correlation between NLN counts and patient prognosis in the setting of gastric cancer is not fully studied. Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer patients were used for analysis in this study. Clinicopathological characteristics, including race, age, gender, and tumor stage, grade, and cause specific survival were collected. Univariate and multivariate Cox proportional hazards model were used to assess the risk factors for survival. As results, X-tile plots identified 3 and 9 as the optimal cutoff value to divide the patients into high, middle and low risk subsets in terms of cause specific survival, and NLN was validated as independently prognostic factor in mulivariate Cox analysis (P < 0.001). Further analysis showed that NLN was a prognosis factor in each N stage. Collectively, our study results firmly demonstrated that the number of NLNs was an independent prognostic factor for gastric cancer patients, and together with the N stage, it could provide more accurate prognostic information than the N stage alone.

Are tumor-infiltrating lymphocytes protagonists or background actors in patient selection for cancer immunotherapy?

INTRODUCTION

Tumor-infiltrating lymphocytes (TILs) are frequently observed in several tumors, reflecting the dynamic process of '"cancer immunoediting"'. Prognostic and predictive values of TILs have been demonstrated in different cancers, proving their pivotal role in clinical outcome. In recent years, new therapies targeting immune checkpoint inhibitors, especially CTLA-4 and PD-1/PDL-1 pathways, have been introduced into clinical practice. In this context, TILs may even have a possible utility as a predictive biomarker for immunotherapy response. Areas covered: In this review, the authors summarize the most relevant knowledge related to TILs. This includes their prognostic and predictive significance in various types of tumour and the recent findings about their potential role in the cancer immunotherapy. Expert opinion: TILs evaluation could lead to a predictive biomarker for immunotherapy effectiveness in several cancer types. Furthermore, typing of TILs subpopulation could have clinical relevance in patient selection for treatment with immune checkpoint inhibitors. However further studies are still needed.

Smad3 mutant mice develop colon cancer with overexpression of COX-2

Colon cancer is the second most common cause of cancer-associated mortality in human populations. The aim of the present study was to identify the role of cyclooxygenase-2 (COX-2) in Smad3 mutant mice, which are known to develop colon cancer. Homozygous Smad3 (-/-) mutant mice were generated from inbred and hybrid Smad3 mouse strains by intercrossing the appropriate heterozygotes. Immunohistochemistry with COX-2 antibody was performed throughout this experiment and the data was validated and cross-checked with reverse transcription-polymerase chain reaction (RT-PCR). Homozygous mutant Smad3 mice were generated and the overexpression pattern of COX-2 was identified by immunohistochemistry and validated with RT-PCR. The results of the present study demonstrated a link between the Smad3 mutant mice, colon cancer and COX-2. In addition, the overexpression pattern of COX-2 in Smad3 mutant mice that develop colon cancer was identified.

Regulation of CTL Infiltration Within the Tumor Microenvironment

The tumor microenvironment consists of a complex milieu of cells and factors that maintain equilibrium between tumor progression and destruction. Characterization of the immune contexture in primary tumors has consistently shown that T lymphocytes are an integral predictor of improved clinical outcome. This is notably true in colorectal carcinoma where high densities of cytotoxic or memory T lymphocytes in the invasive margin and the center of the primary tumor predict better patient survival, a measure termed Immunoscore. Since a high Immunoscore and pre-existing adaptive immune response are significantly correlated with improved clinical outcome, it is essential to understand the mechanisms underlying functional T lymphocyte infiltration into the tumor. The ability of cytolytic and memory T lymphocytes to migrate into tumors is regulated by multiple strategies including T lymphocyte help, homing factors, cytokines, tumor genotype, angiogenesis, lymphangiogenesis, and neurological signals. This chapter will discuss the predominant factors that mediate T-lymphocyte infiltration into tumors and how analysis of these biomarkers determine patients' disease-related survival and predicts response to cancer therapy.

Tumor infiltrating lymphocytes in gastrointestinal tumors: Controversies and future clinical implications

Chronic inflammation following infections, autoimmune diseases or exposure to environmental irritants plays a crucial role in tumor development and influences the host immune response to neoplastic cells. The presence of an anti-tumor immune infiltrate is often associated with better outcomes in gastro-intestinal primary cancers, particularly in those with high microsatellite instability (MSI-H). Immunotherapeutic drugs inhibiting the PD-1 and PD-L1 pathway showed promising results in the treatment of these patients in the metastatic setting. The aim of this review is to resume the role tumor infiltrating lymphocytes (TILs) play in gastrointestinal tumors, underlining their potential value as a prognostic and predictive biomarker. TILs assessment could identify subsets of patients with high extent of TILs and better prognosis, that could be spared from adjuvant systemic treatments. Immune infiltration parameters might be additional predictors of a greater benefit from the immunotherapy with the immune checkpoint blockade.

Conservation of immune gene signatures in solid tumors and prognostic implications

Background

Tumor-infiltrating leukocytes can either limit cancer growth or facilitate its spread. Diagnostic strategies that comprehensively assess the functional complexity of tumor immune infiltrates could have wide-reaching clinical value. In previous work we identified distinct immune gene signatures in breast tumors that reflect the relative abundance of infiltrating immune cells and exhibited significant associations with patient outcomes. Here we hypothesized that immune gene signatures agnostic to tumor type can be identified by de novo discovery of gene clusters enriched for immunological functions and possessing internal correlation structure conserved across solid tumors from different anatomic sites.

Methods

We assembled microarray expression datasets encompassing 5,295 tumors of the breast, colon, lung, ovarian and prostate. Unsupervised clustering methods were used to determine number and composition of gene clusters within each dataset. Immune-enriched gene clusters (signatures) identified by gene ontology enrichment were analyzed for internal correlation structure and conservation across tumors then compared against expression profiles of: 1) flow-sorted leukocytes from peripheral blood and 2) >300 cancer cell lines from solid and hematologic cancers. Cox regression analysis was used to identify signatures with significant associations with clinical outcome.

Results

We identified nine distinct immune-enriched gene signatures conserved across all five tumor types. The signatures differentiated specific leukocyte lineages with moderate discernment overall, and naturally organized into six discrete groups indicative of admixed lineages. Moreover, seven of the signatures exhibit minimal and uncorrelated expression in cancer cell lines, suggesting that these signatures derive predominantly from infiltrating immune cells. All nine immune signatures achieved statistically significant associations with patient prognosis (p<0.05) in one or more tumor types with greatest significance observed in breast and skin cancers. Several signatures indicative of myeloid lineages exhibited poor outcome associations that were most apparent in brain and colon cancers.

Conclusions

These findings suggest that tumor infiltrating immune cells can be differentiated by immune-specific gene expression patterns that quantify the relative abundance of multiple immune infiltrates across a range of solid tumor types. That these markers of immune involvement are significantly associated with patient prognosis in diverse cancers suggests their clinical utility as pan-cancer markers of tumor behavior and immune responsiveness.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2948-z) contains supplementary material, which is available to authorized users.

Patterns and prognostic relevance of PD-1 and PD-L1 expression in colorectal carcinoma

Immune checkpoint blockade targeting the programmed death-1 (PD-1) pathway has shown efficacy in several types of cancers including mismatch-repair-deficient colorectal carcinoma. In some tumor types, programmed death-ligand 1 (PD-L1) expression detected by immunohistochemistry has shown utility as a predictive marker for response to anti-PD-1 therapies. This utility, however, remains to be determined in colorectal carcinoma. In addition, although tumor-infiltrating lymphocytes have been associated with better prognosis in colorectal carcinoma, the prognostic value of PD-1 expression in these lymphocytes and its interaction with PD-L1 expression still await investigation. To address these questions, we performed a pilot study to evaluate the patterns of PD-L1 and PD-1 immunohistochemical expression on colorectal carcinoma cells and their tumor-infiltrating lymphocytes, respectively. Using tissue microarray, we found that 5&percnt; (19&sol;394) of colorectal carcinomas exhibited high tumor PD-L1 expression, and 19&percnt; (76&sol;392) had elevated numbers of PD-1-positive tumor-infiltrating lymphocytes. PD-L1 levels correlated with PD-1 levels (P&lt;0.001), and mismatch-repair-deficient tumors had significantly higher rates of high PD-L1 and PD-1 expression when compared with mismatch-repair-proficient tumors (18&percnt; vs 2&percnt; and 50&percnt; vs 13&percnt;, respectively; P&lt;0.001 for both). Staining intensity was also stronger for both markers in mismatch-repair-deficient tumors. Furthermore, we observed that among patients with mismatch-repair-deficient colorectal carcinoma, PD-1&sol;PD-L1 expression stratified recurrence-free survival in an inter-dependent manner: an association between high PD-1-positive tumor-infiltrating lymphocytes and improved recurrence-free survival (P&equals;0.041) was maintained only when the tumors had low-level PD-L1 expression (P&equals;0.006); patients whose tumors had both high PD-1-positive tumor-infiltrating lymphocytes and high PD-L1 expression had a significantly worse recurrence-free survival (P&lt;0.001). Thus, our results not only provide a foundation for further assessment of PD-L1 immunohistochemistry as a predictive marker for anti-PD-1 therapy in colorectal carcinoma, they also shed light on the prognostic impact of tumor-infiltrating lymphocytes in different subsets of mismatch-repair-deficient colorectal carcinomas.

Number of negative lymph nodes as a prognostic factor in esophageal squamous cell carcinoma

INTRODUCTION

The aim of this study is to investigate the number of negative lymph nodes (NLNs) as a prognostic factor for survival in patients with resected esophageal squamous cell carcinoma.

METHODS

A total of 381 esophageal squamous cell carcinoma patients who had underwent surgical resection as the primary treatment was enrolled into this retrospective study. The impact of number of NLNs on patient's overall survival was assessed and compared with the factors among the current tumor-nodes-metastasis (TNM) staging system.

RESULTS

The number of NLNs was closely related to the overall survival, and the 5-year survival rate was 45.4% for number of NLNs of >20 (142 cases) and 26.4% for NLNs ≤ 20 (239 cases) (P = 0.001). In multivariate survival analysis, the number of NLNs remained an independent prognostic factor (P = 0.002) as did the other current TNM factors. For subgroup analysis, the predictive value of number of NLNs was significant in patients with T3 or T4 disease (P = 0.001) and patients with N1 and N2-3 disease (P = 0.025, 0.043), but not in patients with T1 or T2 disease or patients with N0 disease.

CONCLUSIONS

The number of NLNs, which represents the extent of lymphadenectomy for esophageal squamous cell carcinoma, could impact the overall survival of patients with resected esophageal squamous cell carcinoma, especially among those with nodal-positive disease and advanced T-stage tumor.

Association between Chemotherapy-Response Assays and Subsets of Tumor-Infiltrating Lymphocytes in Gastric Cancer: A Pilot Study

Purpose

The purpose of this pilot study was to evaluate the association between adenosine triphosphate-based chemotherapy response assays (ATP-CRAs) and subsets of tumor infiltrating lymphocytes (TILs) in gastric cancer.

Materials and Methods

In total, 15 gastric cancer tissue samples were obtained from gastrectomies performed between February 2007 and January 2011. Chemotherapy response assays were performed on tumor cells from these samples using 11 chemotherapeutic agents, including etoposide, doxorubicin, epirubicin, mitomycin, 5-fluorouracil (5-FU), oxaliplatin, irinotecan, docetaxel, paclitaxel, methotrexate, and cisplatin. TILs in the tissue samples were evaluated using antibodies specific for CD3, CD4, CD8, Foxp3, and Granzyme B.

Results

The highest cancer cell death rates were induced by etoposide (44.8%), 5-FU (43.1%), and mitomycin (39.9%). Samples from 10 patients who were treated with 5-FU were divided into 5-FU-sensitive and -insensitive groups according to median cell death rate. No difference was observed in survival between the two groups (P=0.216). Only two patients were treated with a chemotherapeutic agent determined by an ATP-CRA and there was no significant difference in overall survival compared with that of patients treated with their physician's choice of chemotherapeutic agent (P=0.105). However, a high number of CD3 TILs was a favorable prognostic factor (P=0.008). Pearson's correlation analyses showed no association between cancer cell death rates in response to chemotherapeutic agents and subsets of TILs.

Conclusions

Cancer cell death rates in response to specific chemotherapeutic agents were not significantly associated with the distribution of TIL subsets.

Pre-treatment neutrophil to lymphocyte ratio as a predictive marker for pathological response to preoperative chemoradiotherapy in pancreatic cancer

An elevated neutrophil to lymphocyte ratio (NLR) has been reported to be associated with the pathological response to neoadjuvant therapies in numerous types of cancer. The aim of the current study was to clarify the association between pre-treatment NLR and the pathological response to preoperative chemoradiotherapy in pancreatic cancer patients. This retrospective analysis included data from 56 consecutive patients whose tumors were completely surgically resected. All patients received preoperative therapy, consisting of gemcitabine-based chemotherapy (alone or in combination with S-1) combined with 40 or 50.4 Gy irradiation, prior to surgery. Predictive factors, including NLR, platelet to lymphocyte ratio (PLR), modified Glasgow prognostic score and prognostic nutrition index, were measured prior to treatment. A comparison was made between those who responded well pathologically (good response group, Evans classification IIb/III) and those with a poor response (Evans I/IIa). NLR was determined to be significantly higher in the poor response group. Multivariate analysis identified an elevated NLR as an independent risk factor for the poor pathological response [odds ratio (OR), 5.35; P=0.0257]. The pre-treatment NLR (≥2.2/<2.2) was found to be a statistically significant predictive indicator of pathological response (P=0.00699). The results demonstrate that pre-treatment NLR may be a useful predictive marker for the pathological response to preoperative therapy in pancreatic cancer patients.

Increased number of negative lymph nodes is associated with improved cancer specific survival in pathological IIIB and IIIC rectal cancer treated with preoperative radiotherapy

Preoperative radiation significantly decreases the number of retrieved lymph nodes (LNs) in rectal cancer, but little is known with respect to the prognostic significance of negative LN (NLN) counts under these circumstances. In this study, Surveillance, Epidemiology, and End Results Program (SEER)-registered ypIII stage rectal cancer patients, and patients from Fudan University Shanghai Cancer Center (FDSCC) were combined and analyzed. The results showed that the survival rate of patients with n (cutoff) or more NLNs increased gradually when n ranged from two to nine. After n reached 10 or greater, survival rates were approximately equivalent. Furthermore, the optimal cutoff value of 10 was validated as an independent prognostic factor in stage ypIIIB and ypIIIC patients by both univariate and multivariate analysis (P < 0.001); the number of NLNs could also stratify the prognosis of ypN(+) patients in more detail. Patients in the FDSCC set validated these findings and confirmed that NLN count was not decreased in the good tumor regression group relative to the poor tumor regression group. These results suggest that NLN count is an independent prognostic factor for ypIIIB and ypIIIC rectal cancer patients, and, together with the number of positive LNs, this will provide better prognostic information than the number of positive LNs alone.

PD-L1 and HLA Class I Antigen Expression and Clinical Course of the Disease in Intrahepatic Cholangiocarcinoma

PURPOSE

More effective therapy is needed for intrahepatic cholangiocarcinoma (ICC). The encouraging clinical results obtained with checkpoint molecule-specific monoclonal antibodies (mAb) have prompted us to investigate whether this type of immunotherapy may be applicable to ICC. The aims of this study were to determine whether (i) patients mount a T-cell immune response to their ICC, (ii) checkpoint molecules are expressed on both T cells and tumor cells, and (iii) tumor cells are susceptible to recognition by cognate T cells.

EXPERIMENTAL DESIGN

Twenty-seven ICC tumors were analyzed for (i) lymphocyte infiltrate, (ii) HLA class I and HLA class II expression, and (iii) PD-1 and PD-L1 expression by T cells and ICC cells, respectively. The results of this analysis were correlated with the clinicopathologic characteristics of the patients investigated.

RESULTS

Lymphocyte infiltrates were identified in all tumors. PD-L1 expression and HLA class I antigen expression by ICC cells was observed in 8 and 11, respectively, of the 27 tumors analyzed. HLA class I antigen expression correlated with CD8(+) T-cell infiltrate. Furthermore, positive HLA class I antigen expression in combination with negative/rare PD-L1 expression was associated with favorable clinical course of the disease.

CONCLUSIONS

ICC patients are likely to mount a T-cell immune response against their own tumors. Defects in HLA class I antigen expression in combination with PD-L1 expression by ICC cells provide them with an immune escape mechanism. This mechanism justifies the implementation of immunotherapy with checkpoint molecule-specific mAbs in patients bearing ICC tumors without defects in HLA class I antigen expression.

Analysis of local chronic inflammatory cell infiltrate combined with systemic inflammation improves prognostication in stage II colon cancer independent of standard clinicopathologic criteria

In Stage II colon cancer, multiple independent studies have shown that a dense intratumoural immune infiltrate (local inflammation) is associated with improved outcomes, while systemic inflammation, measured by various markers, has been associated with poorer outcomes. However, previous studies have not considered the interaction between local and systemic inflammation, nor have they assessed the type of inflammatory response compared with standard clinicopathologic criteria. In order to evaluate the potential clinical utility of inflammatory markers in Stage II colon cancer, we examined local and systemic inflammation in a consecutive series of patients with resected Stage II colon cancer between 2000 and 2010 who were identified from a prospective clinical database. Increased intratumoural chronic inflammatory cell (CIC) density, as assessed by pathologist review of hematoxylin and eosin stained slides, was used to represent local inflammation. Neutrophil-to-lymphocyte ratio (NLR) >5, as calculated from pre-operative full blood counts, was used to represent systemic inflammation. In 396 eligible patients identified, there was a non-significant inverse relationship between local and systemic inflammation. Increased CIC density was significantly associated with improved overall (HR 0.45, p = 0.001) and recurrence-free survival (HR 0.37, p = 0.003). High NLR was significantly associated with poorer overall survival (HR 2.56, p < 0.001). The combination of these markers further stratified prognosis independent of standard high-risk criteria, with a dominant systemic inflammatory response (low CIC/high NLR) associated with the worst outcome (5-year overall survival 55.8%). With further validation this simple, inexpensive combined inflammatory biomarker might assist in patient selection for adjuvant chemotherapy in Stage II colon cancer.