Regulatory mechanisms of T cell activation-From basic research discoveries to a new principle of cancer therapy and the Nobel Prize

Systemic inflammation in colorectal cancer: Underlying factors, effects, and prognostic significance

Systemic inflammation is a marker of poor prognosis preoperatively present in around 20%-40% of colorectal cancer patients. The hallmarks of systemic inflammation include an increased production of proinflammatory cytokines and acute phase proteins that enter the circulation. While the low-level systemic inflammation is often clinically silent, its consequences are many and may ultimately lead to chronic cancer-associated wasting, cachexia. In this review, we discuss the pathogenesis of cancer-related systemic inflammation, explore the role of systemic inflammation in promoting cancer growth, escaping antitumor defense, and shifting metabolic pathways, and how these changes are related to less favorable outcome.

Platelet count, aspirin use, and characteristics of host inflammatory responses in colorectal cancer

Background

Platelets not only contribute to hemostasis but also to the regulation of inflammatory reactions and cancer pathogenesis. We hypothesized that blood platelet count would be associated with systemic inflammation, the densities of tumor infiltrating immune cells, and survival in colorectal cancer (CRC), and these relationships could be altered by aspirin use.

Methods

We measured blood platelet count in a cohort of 356 CRC patients and analyzed its relationships with tumor and patient characteristics including aspirin use, markers of systemic inflammation (modified Glasgow Prognostic Score, mGPS; serum levels of CRP, albumin, and 13 cytokines), blood hemoglobin levels, five types of tumor infiltrating immune cells (CD3, CD8, FoxP3, Neutrophil elastase, mast cell tryptase), and survival.

Results

Platelet count inversely correlated with blood hemoglobin levels (p < 0.001) and positively correlated with serum levels of CRP and multiple cytokines including IL-1RA, IL-4, IL-6, IL-7, IL-8, IL-12, IFNγ, and PDGF-BB (p < 0.001 for all), while aspirin use was not associated with the levels of systemic inflammatory markers. High platelet count was also associated with high mGPS (p < 0.001) but did not show statistically significant multivariable adjusted associations with the densities of tumor infiltrating immune cells. Higher platelet counts were observed in higher tumor stage (p < 0.001), but platelet count or aspirin use were not associated with patient survival.

Conclusions

High platelet count is associated with systemic inflammation in CRC. This study could not demonstrate statistically significant associations between platelet count, aspirin use, and the densities of tumor infiltrating immune cells.

Electronic supplementary material

The online version of this article (10.1186/s12967-019-1950-z) contains supplementary material, which is available to authorized users.