1. UBCH5 Family Members Differentially Impact Stabilization of Mutant p53 via RNF128 Iso1 During Barrett’s Progression to Esophageal Adenocarcinoma
- Author
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Zhuwen Wang, Derek J. Nancarrow, Jason R. Spence, D.K. Turgeon, Michael K. Dame, Daysha Ferrer-Torres, Max A. Hammer, Paramita Ray, David G. Beer, Patrick J. O’Brien, Theodore S. Lawrence, Tonaye Hinton, Joshua H. Wu, Angeline Wu, May San Martinho, and Dipankar Ray
- Subjects
Esophageal Neoplasms ,Mutant ,Barrett’s Esophagus ,RC799-869 ,chemistry.chemical_compound ,RNF128 ,EAC, esophageal adenocarcinoma ,Asparagine ,ANOVA, analysis of variance ,Original Research ,RNF128-UBCH5 Complex ,biology ,Gastroenterology ,Diseases of the digestive system. Gastroenterology ,mRNA, messenger RNA ,Ubiquitin ligase ,Disease Progression ,RNAseq, RNA sequencing ,Gene isoform ,Glycosylation ,Ubiquitin-Protein Ligases ,CpD, CpD (CP-18821) ATCC# CRL-4030 hTERT-immortalized high-grade dysplasia cell line ,p53 Protein Stability ,Adenocarcinoma ,PA, Pro to Ala ,Barrett Esophagus ,CpA, CpA (KR-42421) ATCC# CRL-4027 hTERT-immortalized non-dysplastic metaplasia cell line ,BE, Barrett’s esophagus ,medicine ,Humans ,LGD, low-grade dysplasia ,HGD, high-grade dysplasia ,SCFβ-TrCP1, Skp1-Cul1-F-box protein complex ,Esophageal Adenocarcinoma ,UMI, unique molecular identifier ,hg19, human reference genome ,SE, squamous esophagus ,Hepatology ,HBSS, Hank’s balanced salt solution ,RNA ,UBCH5(A–D), ubiquitin-conjugating enzyme, isoform A–D ,medicine.disease ,WT, wild-type ,chemistry ,NDBE, nondysplastic Barrett’s esophagus ,siRNA, small interfering RNA ,Barrett's esophagus ,Ubiquitin-Conjugating Enzymes ,Iso, isoform ,biology.protein ,Cancer research ,BSA, bovine serum albumin ,Tumor Suppressor Protein p53 - Abstract
Background & Aims TP53 mutations underlie Barrett’s esophagus (BE) progression to dysplasia and cancer. During BE progression, the ubiquitin ligase (E3) RNF128/GRAIL switches expression from isoform 2 (Iso2) to Iso1, stabilizing mutant p53. However, the ubiquitin-conjugating enzyme (E2) that partners with Iso1 to stabilize mutant p53 is unknown. Methods Single-cell RNA sequencing of paired normal esophagus and BE tissues identified candidate E2s, further investigated in expression data from BE to esophageal adenocarcinoma (EAC) progression samples. Biochemical and cellular studies helped clarify the role of RNF128-E2 on mutant p53 stability. Results The UBE2D family member 2D3 (UBCH5C) is the most abundant E2 in normal esophagus. However, during BE to EAC progression, loss of UBE2D3 copy number and reduced expression of RNF128 Iso2 were noted, 2 known p53 degraders. In contrast, expression of UBE2D1 (UBCH5A) and RNF128 Iso1 in dysplastic BE and EAC forms an inactive E2–E3 complex, stabilizing mutant p53. To destabilize mutant p53, we targeted RNF128 Iso1 either by mutating asparagine (N48, 59, and 101) residues to block glycosylation to facilitate β-TrCP1–mediated degradation or by mutating proline (P54 and 105) residues to restore p53 polyubiquitinating ability. In addition, either loss of UBCH5A catalytic activity, or disruption of the Iso1-UBCH5A interaction promoted Iso1 loss. Consequently, overexpression of either catalytically dead or Iso1-binding–deficient UBCH5A mutants destabilized Iso1 to degrade mutant p53, thus compromising the clonogenic survival of mutant p53-dependent BE cells. Conclusions Loss of RNF128 Iso2–UBCH5C and persistence of the Iso1–UBCH5A complex favors mutant p53 stability to promote BE cell survival. Therefore, targeting of Iso1-UBCH5A may provide a novel therapeutic strategy to prevent BE progression., Graphical abstract
- Published
- 2022