1. Identification of a Stable, Non-Canonically Regulated Nrf2 Form in Lung Cancer Cells
- Author
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Ted R. Hupp, Alicja Sznarkowska, Alicja Szabelska-Beresewicz, Robin Fåhraeus, Sara Mikac, Michał Rychłowski, and Alicja Dziadosz
- Subjects
0301 basic medicine ,Nrf2 migration in SDS-PAGE ,Physiology ,Clinical Biochemistry ,Cell ,RM1-950 ,Biochemistry ,digestive system ,environment and public health ,Article ,03 medical and health sciences ,Exon ,0302 clinical medicine ,medicine ,Nrf2 detection ,Molecular Biology ,Transcription factor ,Gene ,Cancer och onkologi ,Chemistry ,Autophagy ,Lipid metabolism ,Cell Biology ,Nrf2 antibodies ,respiratory system ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,Apoptosis ,030220 oncology & carcinogenesis ,Cancer and Oncology ,Therapeutics. Pharmacology ,Homeostasis - Abstract
Nrf2 (nuclear factor erythroid 2 (NF-E2)-related factor 2) transcription factor is recognized for its pro-survival and cell protective role upon exposure to oxidative, chemical, or metabolic stresses. Nrf2 controls a number of cellular processes such as proliferation, differentiation, apoptosis, autophagy, lipid synthesis, and metabolism and glucose metabolism and is a target of activation in chronic diseases like diabetes, neurodegenerative, and inflammatory diseases. The dark side of Nrf2 is revealed when its regulation is imbalanced (e.g., via oncogene activation or mutations) and under such conditions constitutively active Nrf2 promotes cancerogenesis, metastasis, and radio- and chemoresistance. When there is no stress, Nrf2 is instantly degraded via Keap1-Cullin 3 (Cul3) pathway but despite this, cells exhibit a basal activation of Nrf2 target genes. It is yet not clear how Nrf2 maintains the expression of its targets under homeostatic conditions. Here, we found a stable 105 kDa Nrf2 form that is resistant to Keap1-Cul3-mediated degradation and translocates to the nucleus of lung cancer cells. RNA-Seq analysis indicate that it might originate from the exon 2 or exon 3-truncated transcripts. This stable 105 kDa Nrf2 form might help explain the constitutive activity of Nrf2 under normal cellular conditions.
- Published
- 2021