@article{f324f291d83649a9a0d597df8021f18a,
title = "Tumors Responsive to Autophagy-Inhibition: Identification and Biomarkers",
abstract = "Simple Summary Although the principle of personalized medicine has been the focus of attention, many cancer therapies are still based on a one-size-fits-all approach. The same holds true for targeting cancer cell survival mechanism that allows cancer cells to recycle their constituents (autophagy). In the past several indicators of elevated dependence of cancer cells on autophagy have been described. Addition of autophagy-inhibiting agents could be beneficial in treatment of these tumors. The biomarkers and mechanisms that lead to elevated dependence on autophagy are reviewed in the current manuscript. Recent advances in cancer treatment modalities reveal the limitations of the prevalent {"}one-size-fits-all{"} therapies and emphasize the necessity to develop personalized approaches. In this perspective, identification of predictive biomarkers and intrinsic vulnerabilities are an important advancement for further therapeutic strategies. Autophagy is an important lysosomal degradation and recycling pathway that provides energy and macromolecular precursors to maintain cellular homeostasis. Although all cells require autophagy, several genetic and/or cellular changes elevate the dependence of cancer cells on autophagy for their survival and indicates that autophagy inhibition in these tumors could provide a favorable addition to current therapies. In this context, we review the current literature on tumor (sub)types with elevated dependence on autophagy for their survival and highlight an exploitable vulnerability. We provide an inventory of microenvironmental factors, genetic alterations and therapies that may be exploited with autophagy-targeted approaches to improve efficacy of conventional anti-tumor therapies.",
keywords = "autophagy-addiction, biomarkers, personalized medicine, cancer, HYPOXIA-INDUCED AUTOPHAGY, TRANSCRIPTION FACTOR EB, BREAST-CANCER, GLUTAMINE-METABOLISM, TARGETING AUTOPHAGY, RADIATION-THERAPY, PROTEIN-KINASE, CELL-DEATH, GROWTH, RESISTANCE",
author = "Barbeau, {Lydie M. O.} and Keulers, {Tom G. H.} and Rouschop, {Kasper M. A.}",
note = "Funding Information: Clinical trials in different cancer types have been conducted and demonstrated the relative safety of targeting autophagy with CQ or HCQ. Nevertheless, several trials have not been able to provide patients with the maximum intended dose before reaching the maximum tolerated dose [42]. To date, it remains impossible to measure autophagy inhibition in patients at the site where autophagy inhibition is intended, the tumor, without taking sequential biopsies. In most circumstances, this is not possible or undesired due to the associated risk and extra burden for the patient. Whether sufficient autophagy inhibition in the tumor is reached to successfully increase therapy efficacy remains a matter of investigation. Without having tools available that indicate whether sufficient autophagy inhibition is reached, the evaluation of the success of autophagy-inhibitory strategies will be dependent on improving outcome for patients after therapy. Patient stratification and selection for tumor types with biomarkers that have shown promising results in preclinical studies will determine the feasibility of autophagy inhibition in oncological care. Author Contributions: L.M.O.B. reviewed and analyzed available literature and wrote the manuscript, Author Contributions: L.M.O.B. reviewed and analyzed available literature and wrote the manuscript, T.G.H.K. have read and agreed to the published version of the manuscript. wrote the manuscript, K.M.A.R. designed the scope of the review and wrote the manuscript. All authors have Funding: These studies received financial support from the Dutch Cancer Society (KWF grant 12,276 and UM2015-7735 to K.R.) and Zeldzame Ziekten Fonds (ZZF grant to K.R.). Funding: These studies received financial support from the Dutch Cancer Society (KWF grant 12,276 and UM2015-7735 to K.R.) and Zeldzame Ziekten Fonds (ZZF grant to K.R.). Publisher Copyright: {\textcopyright} 2020 by the authors. Licensee MDPI, Basel, Switzerland.",
year = "2020",
month = sep,
doi = "10.3390/cancers12092463",
language = "English",
volume = "12",
journal = "Cancers",
issn = "2072-6694",
publisher = "Multidisciplinary Digital Publishing Institute (MDPI)",
number = "9",
}