Extraterritorial osteoclast traits of primary cancer cells

Abstract

Cancer cells seem to originate in the epithelium however the majority of their phenotypic functions and traits do not resemble an epithelian but a preosteoclast/osteoclast cell. This applies not only to bone metastases but also the primary tumor, where these characteristics are exhibited extraterritorially. The most remarkable common features between osteoclasts and cancer cells include, among many others, matrix-resolving properties, hormone and neuronal dependence, coupling with mesenchymal cells, migrating and transmigrating properties, neurogenetic activities, trafficking to the bone, immune deviation, sensitivity to antirheumatics, bisphosphonates, polyphenols and steroids, constitutive activation of NFkappaB, and the same cytokine and chemokine signalling pathways. Below we present the corresponding findings reported in scientific publications and discuss various aspects of this congruency between cancer cells and preosteoclasts/osteoclasts.