Alternatively, IL-1⍺ and IL-1β secretion by metastasis-initiating breast cancer cells [90] may activate CAFs to secrete ECM-remodeling factors such as matrix metalloproteinases (MMPs), LOX enzymes, Periostin, Tenascin-C and Versican, among others, thus providing a favorable niche for organ colonization [82,89,91]. This evidence concerns the gene IL1B and breast cancer.