The top significant hit was a missense mutation (Y113C) in the MAP1LC3B/LC3B (microtubule associated protein 1 light chain 3 beta) protein, which occurred at a significant frequency in cancer, and was detected in early stages in primary tumors of patients with known tumor lineage.
Our study highlights the role of oxidation of MiT-TFE transcription factors in ROS-linked autophagy, and provides novel mechanism that MiT-TFE transcription factors-mediated transcriptional control of autophagy may govern cell homeostasis in response to oxidative stress, a biological process tightly linked to human diseases including neurodegenerative diseases and cancer.<b>Abbreviations</b>: Bafi A1: bafilomycin A<sub>1</sub>; EBSS: Earle's balanced salt solution; EGFP: enhanced green fluorescent protein; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MTORC1: mechanistic target of rapamycin kinase complex 1; ROS: reactive oxygen species; RPS6KB/p70S6K: ribosomal protein S6 kinase B; TFEB: transcription factor EB; WT: wild type.
The difference in the prognostic significance of LC3B between oropharyngeal and oral cavity SCCs further supports the biological differences between these malignancies.
Metformin triggered autophagy (LC3B expression) was identified to interplay with apoptosis to attenuate the drug effect and postpone cancer cell death.
LC3B-II protein levels were significantly increased in cachectic cancer patients suggesting either increased autophagosome formation or reduced autophagosome turnover.