Background:Inflammation contributes to the pathogenesis of colorectal cancer (CRC), and cytokine levels are altered during colorectal carcinogenesis.Methods:The serum levels of 13 cytokines and their relation to clinical and pathological parameters, and systemic inflammatory response (mGPS, CRP and neutrophil–lymphocyte ratio), were analysed from a prospective series of 148 CRC patients and 86 healthy age- and sex-matched controls.Results:CRC patients had higher serum platelet-derived growth factor, interleukin (IL)-6, IL-7, and IL-8 levels and lower monocyte chemotactic protein-1 (MCP-1) levels than the controls. A logistic regression model for discriminating the patients from the controls – including the five most predictive cytokines (high IL-8, high IL-6, low MCP-1, low IL-1ra, and low IP-10) – yielded an area under curve value of 0.890 in receiver operating characteristics analysis. Serum cytokines showed distinct correlation with other markers of systemic inflammatory response, and advanced CRCs were associated with higher levels of IL-8, IL-1ra, and IL-6. A metastasised disease was accompanied by an orientation towards Th2 cytokine milieu.Conclusion:CRC is associated with extensive alterations in serum cytokine environment, highlighting the importance of studying relative cytokine level alterations. Serum cytokine profile shows promise in separating CRC patients from healthy controls but its clinical value is yet to be confirmed.

AimsTo define the occurrence of KRAS and BRAF mutations, microsatellite instability (MSI), and MGMT and hMLH1 methylation and expression in colorectal serrated adenocarcinoma.Methods and resultsKRAS codon 12/13 and 59/61 and BRAF V600E mutations, MSI, and MGMT and hMLH1 methylation and expression in 42 serrated adenocarcinomas and 17 serrated adenomas were compared with those in 59 non-serrated colorectal carcinomas (CRCs) and nine adenomas. KRAS and BRAF mutations were observed in 45% and 33% of serrated adenocarcinomas and in 27% and 0% of non-serrated CRCs (P < 0.001). The KRAS c12G→A transition was the predominant type of mutation in serrated adenocarcinomas. Forty-two per cent of BRAF-mutated serrated adenocarcinomas showed high-level MSI (MSI-H) (P = 0.075), 100% showed hMLH1 methylation (P = 0.001) and 90.9% showed MGMT methylation (P = 0.019). Fifty-six per cent of serrated adenocarcinomas with microsatellite stability/low-level microsatellite instability harboured KRAS mutations. In non-serrated cancers, KRAS mutations were not associated with MSI status.ConclusionsA high combined mutation rate (79–82%) of KRAS and BRAF in serrated adenomas and adenocarcinomas indicates that mitogen-activated protein kinase activation is a crucial part of the serrated pathway. BRAF mutations are specific for serrated adenocarcinoma and identify a subset of serrated adenocarcinomas with gene methylation and a tendency for MSI-H. A high frequency of KRAS mutations in serrated adenocarcinomas suggests that a significant proportion of KRAS-mutated CRCs originate from serrated precursors, thus challenging the traditional model of Vogelstein.

Increased inflammatory cell infiltration correlates to improved survival in colorectal cancer (CRC). Development and progression of CRC is associated with alterations in serum cytokine levels but their significance is not well defined. In this study, we investigated the relationships between the serum levels of 13 cytokines and the densities of eight types of tumor infiltrating inflammatory cells and their impact on disease-free survival (DFS), cancer-specific survival (CSS) and overall survival (OS) in a prospectively recruited group of 147 CRC patients. There were strong positive correlations between the serum concentrations of different cytokines, as well as between the different types of tumor infiltrating immune cells, whereas the associations between serum cytokines and tumor infiltrating immune cells were generally weak. High serum IL-12 levels associated with increased densities of peritumoral CD8 1 T cells, intraepithelial CD3 1 T cells and intratumoral neutrophils, while high serum CCL4 levels associated with increased densities of peritumoral CD68 1 cells. In multivariate survival models, increased infiltration of intraepithelial CD3 1 T cells and increased serum CCL4 associated with improved DFS, whereas higher intratumoral CD83 1 dendritic cell density and increased serum interferon gamma levels associated with improved CSS and OS. Also high density of peritumoral CD3 1 T cells associated with improved CSS. In conclusion, serum cytokines and tumor infiltrating immune cells in CRC represent entities with high intragroup correlations but relatively weak intergroup correlations. The results suggest that tumor infiltrating CD3 1 T cells, CD83 1 dendritic cells, serum CCL4 and serum interferon gamma represent relevant markers of disease outcome.

Background:Endostatin, a fragment of collagen XVIII, is an endogenous angiogenesis inhibitor with anti-tumour functions. However, elevated circulating endostatin concentrations have been found in several human cancers including colorectal cancer (CRC).Methods:Serum endostatin levels were measured by enzyme-linked immunoassay from a series of 143 patients with CRC and from 84 controls, and correlated with detailed clinicopathological features of CRC, serum leukocyte differential count and C-reactive protein (CRP) levels.Results:Patients with CRC had higher serum endostatin levels than the controls (P=0.005), and high levels associated with age, tumour invasion through the muscularis propria and poor differentiation, but not with metastases. Endostatin levels showed a positive correlation with the markers of systemic inflammatory response and a negative correlation with the densities of tumour-infiltrating mast cells and dendritic cells. Collagen XVIII was expressed in tumour stroma most strikingly in blood vessels and capillaries, and in the muscle layer of the bowel wall.Conclusions:Elevated endostatin levels in CRC correlate with systemic inflammation and invasion through the muscularis propria. Increased endostatin level may be a result of invasion-related cleavage of collagen XVIII expressed in the bowel wall. The negative correlations between serum endostatin and intratumoural mast cells and immature dendritic cells may reflect angiogenesis inhibition by endostatin.