BACKGROUNDFor decades, researchers have strived to analyze the process of tumour formation and progression. Despite the immense accumulation of knowledge, cancer still remains one of the biggest burdens of our society today. According to the WHO, nearly one in six deaths worldwide was attributed to cancer in 2020. Hence, it is crucial to revisit and build upon recent achievements to improve our understanding of this disease.One of the most important concepts to describe the growth and spreading of tumour cells in patients over time is the phenotype-switching model. 1 This model was first discovered in melanoma and is also applicable to other tumours. It is based on the idea that tumour cells can exist in two different cellular states. On the one hand, they exhibit a high proliferative activity with a high rate of glycolysis, but low migrative and invasive capacity. On the other hand, cells can exist in a state hallmarked by up-regulation of migrative and invasive behaviour with inflammation-related pathways being increased. Therefore, increasing evidence supports the idea that tumours progress to metastasis by dynamically switching from a local, proliferative state to a highly migrative state, whichThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.