Inflammation and breast cancer

Abstract

The relationship between breast cancer (BC) and inflammation remains unclear.Several well-established risk factors for BC, such as advancing age, obesity and late age of first pregnancy, are associated with increased levels of circulating proinflammatory cytokines and systemic inflammation.Tumor-associated macrophages may comprise 50% of the breast tumor mass and the extent of infiltration is associated with increased angiogenesis and poor prognosis.T-lymphocyte infiltration into invasive breast carcinoma is associated with extensive and higher-grade ductal carcinoma in situ and invasive carcinoma.Acute activation of B cells has an anticancer role; controversially, some studies suggest that B-lymphocytic infiltration may play a role in tumor progression.Myleoid-derived suppressor cells may contribute to tumor-induced bone disease. The prognostic value of breast tumor infiltration with mature dendritic cells in BC is limited.Increased levels of IL-6, IL-1b and TNF-a are associated with poorer prognosis.CLL5 and CLL2 chemokines are associated with advanced tumor growth and metastases.Major anti-inflammatory cytokines, such as IL-4, IL-10, IL-13, IL-35 and COX-2, have been found to be associated with aggressive BC, including larger tumor size and higher grade.A meta-analysis of 38 studies showed that the use of nonsteroidal anti-inflammatory drugs leads to a reduced risk of BC.NF-kB activity has been associated with estrogen receptor-negative tumors and a more aggressive phenotype in estrogen receptor-positive tumors.

Genetic polymorphisms in inflammatory response genes and their associations with breast cancer risk

“…Single nucleotide polymorphisms (SNPs) have been extensively investigated for their associations with the risk of various cancers ( 6 - 11 ). As inflammation is caused by a molecular network underlying breast carcinogenesis ( 12 ), we propose that SNPs within inflammatory response genes could modify breast cancer predisposition risk. The associations of various inflammatory response gene polymorphisms with breast cancer risk in the Chinese population, especially the East Chinese population, have been understudied.…”