IL1B and neoplasm: In another study, soluble factors (identified as extracellular matrix peptides) in LLC1 tumor cell conditioned media induced bone marrow derived cell secretion of pro-inflammatory cytokines, including IL-1β, IL-6, and tumor necrosis factor α (TNF-α), whereas serum-free media and 3T3 conditioned media had no effect on cytokine production [44].