ß-Catenin Drives Butyrophilin-like Molecule Loss and γδ T-cell Exclusion in Colon Cancer.

Intraepithelial lymphocytes (IEL) expressing γδ T-cell receptors (γδTCR) play key roles in elimination of colon cancer. However, the precise mechanisms by which progressing cancer cells evade immunosurveillance by these innate T cells are unknown. Here, we investigated how loss of the Apc tumor suppressor in gut tissue could enable nascent cancer cells to escape immunosurveillance by cytotoxic γδIELs. In contrast with healthy intestinal or colonic tissue, we found that γδIELs were largely absent from the microenvironment of both mouse and human tumors, and that butyrophilin-like (BTNL) molecules, which can critically regulate γδIEL through direct γδTCR interactions, were also downregulated in tumors. We then demonstrated that ß-catenin activation through loss of Apc rapidly suppressed expression of the mRNA encoding the HNF4A and HNF4G transcription factors, preventing their binding to promoter regions of Btnl genes. Reexpression of BTNL1 and BTNL6 in cancer cells increased γδIEL survival and activation in coculture assays but failed to augment their cancer-killing ability in vitro or their recruitment to orthotopic tumors. However, inhibition of ß-catenin signaling via genetic deletion of Bcl9/Bcl9L in either Apc-deficient or mutant ß-catenin mouse models restored Hnf4a, Hnf4g, and Btnl gene expression and γδ T-cell infiltration into tumors. These observations highlight an immune-evasion mechanism specific to WNT-driven colon cancer cells that disrupts γδIEL immunosurveillance and furthers cancer progression.

Fueling the flames of colon cancer - does CRP play a direct pro-inflammatory role?

Background: Systemic inflammation, diagnostically ascribed by measuring serum levels of the acute phase reactant C-reactive protein (CRP), has consistently been correlated with poor outcomes across cancer types. CRP exists in two structurally and functionally distinct isoforms, circulating pentameric CRP (pCRP) and the highly pro-inflammatory monomeric isoform (mCRP). The aim of this pilot study was to map the pattern of mCRP distribution in a previously immunologically well-defined colon cancer (CC) cohort and explore possible functional roles of mCRP within the tumor microenvironment (TME). Methods: Formalin-fixed, paraffin-embedded (FFPE) tissue samples from 43 stage II and III CC patients, including 20 patients with serum CRP 0-1 mg/L and 23 patients with serum CRP >30 mg/L were immunohistochemically (IHC) stained with a conformation-specific mCRP antibody and selected immune and stromal markers. A digital analysis algorithm was developed for evaluating mCRP distribution within the primary tumors and adjacent normal colon mucosa. Results: mCRP was abundantly present within tumors from patients with high serum CRP (>30 mg/L) diagnostically interpreted as being systemically inflamed, whereas patients with CRP 0-1 mg/L exhibited only modest mCRP positivity (median mCRP per area 5.07‰ (95%CI:1.32-6.85) vs. 0.02‰ (95%CI:0.01-0.04), p<0.001). Similarly, tissue-expressed mCRP correlated strongly with circulating pCRP (Spearman correlation 0.81, p<0.001). Importantly, mCRP was detected exclusively within tumors, whereas adjacent normal colon mucosa showed no mCRP expression. Double IHC staining revealed colocalization of mCRP with endothelial cells and neutrophils. Intriguingly, some tumor cells also colocalized with mCRP, suggesting a direct interaction or mCRP expression by the tumor itself. Conclusion: Our data show that the pro-inflammatory mCRP isoform is expressed in the TME of CC, primarily in patients with high systemic pCRP values. This strengthens the hypothesis that CRP might not only be an inflammatory marker but also an active mediator within tumors.

Systemic Inflammation Associates With a Myeloid Inflamed Tumor Microenvironment in Primary Resected Colon Cancer-May Cold Tumors Simply Be Too Hot?

Systemic inflammation measured by the acute-phase protein CRP associates with poor outcome across cancer types. In contrast, local tumor-associated inflammation, primarily evaluated by T-lymphocytes, correlates with favorable prognosis. Yet, little is known whether these two responses are related or opposing processes and why elevated CRP in relation to cancer is detrimental for clinical outcome. As proof of concept, we developed a platform combining multiplexed IHC and digital imaging, enabling a virtual readout of both lymphoid and myeloid immune markers and their spatial patterns in the primary tumors of resected stage II and III colon cancer (CC) patients with and without accompanying systemic inflammation. Twenty-one patients with elevated CRP (>30 mg/l) and 15 patients with low CRP (<10 mg/l) were included in the analyses. Whole slides from the primary tumors were stained for markers of adaptive (CD8+, CD4+, foxp3 regulatory T cells, CD20+ B cells) and innate (CD68+ macrophages, CD66b+ neutrophils) immunity and the immune checkpoint molecule PD-L1. Associations between individual immune markers, preoperative CRP values, mismatch repair status (MMR), and risk of recurrence or death were assessed. Unsupervised hierarchical clustering was used to explore whether distinct immune phenotypes were present. Tumors from systemically inflamed patients (CRP >30 mg/l) displayed significantly more myeloid features in terms of higher densities of CD66b+neutrophils (p = 0.001) and CD68+macrophages (p = 0.04) and less lymphoid features (lower CD8 T cell, p = 0.03, and foxp3 regulatory T cell densities, p = 0.03) regardless of MMR status. Additionally, systemically inflamed patients harbored lower mean distances between neutrophils and tumor cells within the TME. Intriguingly, microsatellite instable (MSI) tumor status correlated with systemic inflammation. However, using a combinatorial approach, we found that regardless of an adaptive composite score (compounded CD4+ and CD8+ T cells), a high innate score (CD66b+ neutrophils and CD68+ macrophages) associated significantly with elevated CRP. In conclusion, tumor-associated systemic inflammation correlated with a myeloid-dominated TME in a small cohort of resectable CC patients. Our data highlight the importance of a comprehensive immune classification of tumors including players of innate immunity and support a role for CRP as an informative biomarker of the immune response taking place at the tumor site.

The prognostic role of systemic inflammation in patients undergoing resection of colorectal liver metastases: C-reactive protein (CRP) is a strong negative prognostic biomarker.

BACKGROUND AND OBJECTIVES: Systemic inflammation has been associated with poor survival in several tumor types, but has been less extensively studied in resectable metastatic disease. The aim of the present study was to evaluate the prognostic role of CRP in colorectal cancer patients with liver metastases (CRLM) compared to conventional tumor- and patient-related clinicopathological features as well as other indicators of the systemic inflammatory response (SIR). METHODS: A multinational retrospective study of 492 CRLM patients undergoing potentially curative resection of liver metastases between 1999 and 2009. Clinicopathological findings and the SIR markers CRP, hypoalbuminemia, and their combined Glasgow Prognostic Score (GPS) were analyzed. RESULTS: Multivariate analysis showed that preoperative CRP >10 mg/L was a strong predictor of compromised survival (HR = 1.72, 95%CI 1.84-2.50, P < 0.01). Patients with CRP ≤10 mg/L had a median survival of 4.27 years compared to only 47 days in patients with CRP ≥30 mg/L (P < 0.01). Similarly, increased GPS was independently predictive of poor survival (HR 1.67, 95%CI 1.22-2.27, P < 0.01), but hypoalbuminemia alone did not have significant prognostic value. CONCLUSIONS: CRP alone is a strong prognostic factor, following curative resection of colorectal liver metastases and should be taken into consideration when selecting treatment strategies in CRLM patients. J. Surg. Oncol. 2016;114:895-899. © 2016 2016 Wiley Periodicals, Inc.

Fever and the use of paracetamol during IL-2-based immunotherapy in metastatic melanoma.

Fever is frequently observed in conjunction with interleukin-2 (IL-2)-based immunotherapy. Traditionally, fever has been regarded as an undesirable side effect and treated with fever-lowering drugs. However, new insights in tumor immunology suggest that elevated temperature may facilitate a more effective antitumor immune response. The purpose of this retrospective study was to examine the potential role of the IL-2-induced fever in melanoma patients treated with or without paracetamol in two consecutive cohorts. One hundred and seventy-nine patients with metastatic melanoma treated with a modified decrescendo regimen of IL-2 and Interferon (IFN) between 2004 and 2010 were retrospectively studied. 87 patients treated before 2007 received paracetamol as part of the treatment schedule, and 92 patients treated after 2007 did not receive paracetamol routinely. Body temperature was analyzed as dichotomized and continuous variables and correlated to objective tumor response and overall survival using logistic regression and Cox proportional hazard analysis. Patients experiencing peak temperature of ≥ 39.5 °C had a median OS of 15.2 months compared to 8.7 months among patients with lower temperatures (P = 0.01). In the multivariate analysis, peak temperature of ≥ 39.5 °C (HR 0.53; P = 0.026) and high mean temperature (HR 0.56; P = 0.004) were independent prognostic factors for improved survival. We suggest high fever as a biomarker for improved survival in melanoma patients treated with IL-2/IFN. The routine use of fever-reducing drugs during immunotherapy can therefore be questioned. More studies are needed to evaluate the role of fever and the use of antipyretics during cytokine-based immunotherapy.

Sorafenib in advanced hepatocellular carcinoma: a nationwide retrospective study of efficacy and tolerability.

BACKGROUND: Advanced HCC is a clinical challenge with limited treatment options. The multikinase inhibitor sorafenib is the first and only agent showing a survival benefit in these patients. In this study we evaluate the efficacy and tolerability of sorafenib in an unselected patient population. Furthermore we explore the role of alpha-fetoprotein (αFP) as a potential biomarker for treatment efficacy and correlation to survival. METHODS: Seventy-six patients with advanced HCC, not eligible for locoregional therapy, treated with sorafenib between 2007 and 2009 were included. Followup was until 2011. RESULTS: Patients in PS 0-1 had a median overall survival (mOS) of 6.2 months, compared to 1.8 months in patients with poorer PS (P = 0.005). Child-Pugh A patients had a mOS of 6.6 months versus 3.6 months among patients in Child-Pugh B or C (P = 0.0001). Serum αFP ≥ 200 at baseline was prognostic for a shorter survival. All patients with radiologically verified tumor response and baseline αFP ≥ 200 experienced a significant decline in αFP within the first four weeks of treatment. CONCLUSION: The survival of patients with advanced HCC treated with sorafenib is dependent on performance status and liver function. Treatment of patients with compromised liver function and poor performance status cannot be recommended. The correlation between αFP and objective tumor response warrants further investigation.