AUTHOR=Hahne Jens C. , Valeri Nicola TITLE=Non-Coding RNAs and Resistance to Anticancer Drugs in Gastrointestinal Tumors JOURNAL=Frontiers in Oncology VOLUME=Volume 8 - 2018 YEAR=2018 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2018.00226 DOI=10.3389/fonc.2018.00226 ISSN=2234-943X ABSTRACT=Non-coding RNAs are important regulators of gene expression and transcription. It is well established that impaired non-coding RNA expression especially the one of long non-coding RNAs and microRNAs is involved in a number of pathological conditions including cancer. Non-coding RNAs are responsible for the development of resistance to anticancer treatments as they regulate drug resistance-related genes, affect intracellular drug concentrations, induce alternative signalling pathways, alter drug efficiency via blocking cell cycle regulation and DNA damage response. Furthermore, they can prevent therapeutic-induced cell death and promote epithelial-mesenchymal transition and elicit non-cell autonomous mechanisms of resistance. In this review we summarise the role of non-coding RNAs for different mechanisms resulting in drug resistance (e.g. drug transport, drug metabolism, cell cycle regulation, regulation of apoptotic pathways, cancer stem cells and epithelial-mesenchymal transition) in the context of gastrointestinal cancers.