The Links between Inflammation and Cancer

Abstract

Inflammation is a crucial function of the innate immune system that protects against pathogens and initiates specific immunity. Acute inflammation is a tightly controlled process that normally resolves via active repair processes, but this does not always happen. Many of the diseases of middle and old age may be driven, at least in part, by chronic, “smouldering”, unresolved and often subclinical inflammation. In the past 5 years or so there has been great interest in the role of chronic inflammatory processes in malignant disease. It appears that neoplastic tissue selects for the type and extent of inflammation most favourable to tumour growth and progression. There is accumulating evidence that the cells and the chemical mediators of chronic inflammation are found in cancers; general or cell‐specific gene inactivation of key inflammatory mediators influences neoplastic progression, and population‐based studies link inflammatory disease or non‐steroidal anti‐inflammatory drug (NSAID) use with risk of some cancers. If genetic damage is the match that lights the fire of cancer, inflammation can be considered as a fuel that feeds the flame .

Accessories to the Crime: Functions of Cells Recruited to the Tumor Microenvironment

“…And, how can their roles and functional importance be clarified across the broad spectrum of human malignancies, factoring in differences to the histologically distinct stages of tumor development and progression, the molecular genetic subtypes being recognized for many human cancers, and the individual patient to patient variations that are increasingly appreciated? Certainly, there is epidemiological evidence associating abundance of particular stromal cell types-density of neovascularization and abundance of tumorpromoting versus tumor antagonizing IICs-with prognosis in various human cancers (Balkwill and Mantovani, 2011). Beyond epidemiology, the path toward clarification is challenging.…”