Inflammation fuels tumor progress and metastasis

Abstract

Inflammation is a beneficial response that can remove pathogens, repair injured tissue and restore homeostasis to damaged tissues and organs. However, increasing evidence indicate that chronic inflammation plays a pivotal role in tumor development, as well as progression, metastasis, and resistance to chemotherapy. We will review the current knowledge regarding the contribution of inflammation to epithelial mesenchymal transition. We will also provide some perspectives on the relationship between ER-stress signals and metabolism, and the role of these processes in the development of inflammation.

Figure 1. Schematic diagram of the signaling pathways associated with Snail and Twist induced EMT

An integrated and complex signaling network, including RTKs, TGF-β, Notch, Wnt, TNF-α, and BMPs signaling pathways, activate Snail and Twist, resulting in the EMT induction. Snail functions as a transcriptional repressor to suppress genes that prevent cell migration and growth (such as E-cadherin and FBP1); whereas Twist acts as a transcriptional activator to induce genes that favor cell migration and proliferation (Wnt5A) in an analogy of a moving car that has disabled brakes and an accelerating engine.