Cancer tissue engineering - new perspectives in understanding the biology of solid tumours - a critical review

Understanding cancer biology is a major challenge of this century. The recent insight about carcinogenesis mechanisms, including the role exerted by the tumour microenvironment and cancer stem cells in chemoresistance, relapse and metastases, has made it self-evident that only new cancer models, with increased predictability, will allow the development of efficient therapies. The aims of this critical review are to briefly summarise and discuss the key aspects in the development of three-dimensional biomimetic tumour models. In this review, tissue engineering (TE) retains a valuable and highly exploitable potential. Tissue-engineered tumour models can account for a number of advantages, such as reproducibility, tailourable complexities (e.g., cell types, size, chemistry, architecture, mechanical properties, bioresorption and diffusion gradients) and ethical sustainability, making them suitable tools not only for mimicking normal tissue regeneration, but also, and most interestingly, for cancer development and resistance to therapies. Finally, we will focus upon interesting studies recently reported in the published literature about cancer TE, grouping their findings by tumour type, in order to give a snapshot picture of the current achievements to those cancer scientists, who are wishing to approach the field of TE. A special focus was given to pancreas, breast and prostate tumours.