GSTT2 Switches from a Homeostatic Antioxidant to a Cell-Cycle-Coupled Factor in Therapy-Resistant Esophageal Adenocarcinoma
GSTT2 expression increases in treatment-resistant esophageal adenocarcinoma, indicating a potential shift in its role from antioxidant to cell cycle regulator.
Where it sits
this study against the rest of the glutathione (gsh) corpusSummary and findings
This study investigates the expression and role of GSTT2 in esophageal adenocarcinoma (EAC) across different ancestry groups. It was found that GSTT2 mRNA levels were highest in normal squamous esophagus and increased in treatment-resistant EAC. The research utilized various methods including FISH, immunofluorescence, and transcriptomics to analyze GSTT2's involvement in cancer progression.
Abstract
Glutathione S-transferase theta 2 (GSTT2) is highly expressed in esophageal tissues from African American (AA) compared with European American (EA) individuals, but its localization, regulation, and relevance to esophageal adenocarcinoma progression remain unclear. Here, we combined FISH, immunofluorescence, patient-derived culture models, cell-cycle synchronization, biochemical perturbation, and transcriptomics to define GSTT2 expression in normal and neoplastic esophageal contexts. In developing and adult esophagus, GSTT2 mRNA and protein were broadly distributed across squamous epithelium and lamina propria, co-localizing with p63-positive basal/progenitor cells and extending into differentiated compartments, with no major ancestry-associated differences in spatial patterning. In Barrett’s esophagus, GSTT2 protein was retained in metaplastic columnar epithelium and slightly elevated in dysplastic versus adjacent non-dysplastic regions. GSTT2 mRNA was highest in normal squamous esophagus, reduced during Barrett’s-to-adenocarcinoma progression, but increased in treatment-resistant esophageal adenocarcinoma (EAC). In resistant EAC, GSTT2 co-expression shifted from homeostatic antioxidant programs to proliferation and mitotic pathways, including G2-M checkpoint, E2F targets, and Reactome cell cycle, with leading-edge regulators CDK1 and CDC20. Sequence analysis identified putative APC/C and FBXW7 recognition motifs. In synchronized cells, GSTT2 abundance declined during S-G2/M and increased during mitotic exit/early G1 in cytosolic and membrane fractions. Forskolin, a dual inhibitor of FBXW7 and CDC20, stabilized GSTT2 and rescued CDC20- or FBXW7-associated loss, implicating APC/C-CDC20 and FBXW7 pathways in GSTT2 turnover. Distinctly, however, in EAC cells, CDC20 was found to be a cooperative partner stabilizing GSTT2. These findings identify GSTT2 as a spatially widespread, ancestry-associated, cell-cycle-regulated protein with potential oncogenic roles in EAC resistance.
Background
The study appears to address the role of GSTT2 in esophageal adenocarcinoma, particularly in the context of therapy resistance. GSTT2 may have a dual role, switching from an antioxidant to a cell-cycle-related factor. Understanding this switch could provide insights into cancer biology and potential therapeutic targets.
Methods
Not reported in abstract.
Results
Not reported in abstract.
Interpretation
Without data from the abstract, it is unclear how the findings compare to existing literature or their clinical significance. The study's implications for practice remain speculative without specific results.
Key findings
- Not reported in abstract.
Limitations
- Abstract not available
- Preprint status
- Unknown sample size
- Unknown study design