It’s now clear that for cancer, malignant cells are only part of the problem; according to researchers at this year’s American Association for Cancer Research (AACR) meeting, the diverse mass of non-malignant cells surrounding, supporting, and infiltrating the tumor that comprise the tumor microenvironment (TME) also plays a key role in the progression of disease.
“It’s not a single rogue cell; it takes a village [of cells],” said Mina Bissell, a cell biologist at the Lawrence Berkeley National Laboratory in California
Frances Balkwill of Barts Cancer Institute in London presented her work on the TME of certain ovarian cancers. Using mouse transplant models, Balkwill has demonstrated that up to 50 percent of primary and metastatic tumor mass is comprised of CD4+, CD8+ macrophages, B cells, and fibroblasts surrounding the tumor itself. Balkwill said that these cells, together with inflammatory cytokines including interluekin-6 (IL-6), appear to be responsible for the growth and spread of tumors. She also presented clinical data showing that an anti-IL-6 antibody results in rapid reduction of inflammation and tumor mass, and thus may open a window of opportunity for immunotherapy.