Study Identifies GADD45A as a Tumor Suppressor in Hepatocellular Carcinoma

Reduced expression of the stress-responsive nuclear protein GADD45A is significantly associated with advanced pathological stages and poorer survival outcomes in patients with liver hepatocellular carcinoma, according to a study published in Clinical and Experimental Medicine. Analyzing transcriptomic and clinical records, researchers established GADD45A deficiency as an independent prognostic biomarker for the malignancy.

To assess the clinical implications and biological landscape of GADD45A, investigators examined transcriptomic data from The Cancer Genome Atlas and Gene Expression Omnibus repositories. Statistical evaluations using Wilcoxon tests, Kaplan–Meier curves, and Cox models showed significant downregulation of GADD45A in liver hepatocellular carcinoma, while biological pathways and immune infiltration profiles were mapped through STRING, Gene Set Enrichment Analysis, and TIMER2.0.

The bioinformatic analysis demonstrated that low GADD45A expression is positively linked to an exhausted immune microenvironment within tumors. This state was characterized by elevated levels of key inhibitory immune checkpoints, specifically PDCD1, CTLA4, and LAG3.

In vitro experiments in cultured cells further supported a cell-intrinsic tumor suppressor role. Overexpression of GADD45A in modified HepG2 cells—assessed through cytotoxicity, qRT-PCR, Western blot, CCK-8, colony formation, wound healing, and Transwell assays—markedly reduced cell proliferation, colony formation, and metastasis while increasing sensitivity to cisplatin, with migration, invasion, and Western blot assays in Huh-7 cells confirming these cellular effects.

The research addressed an important gap in liver cancer biology, where the precise role and immune implications of GADD45A in liver hepatocellular carcinoma had remained poorly characterized. Although recognized as a stress-responsive nuclear protein, the clinical significance and cellular activities of GADD45A required detailed investigation. To resolve these questions, the study evaluated the prognostic value, immune landscape, and cell-intrinsic functions of the protein by combining computational analyses of public patient repositories with comprehensive laboratory validation experiments.

For the clinical and transcriptomic evaluations, researchers analyzed patient data sourced from The Cancer Genome Atlas and the Gene Expression Omnibus. Statistical assessments using Wilcoxon tests, Kaplan–Meier survival curves, and Cox regression models demonstrated that GADD45A expression was significantly downregulated in liver hepatocellular carcinoma. Furthermore, this deficiency correlated strongly with advanced pathological disease stages and reduced patient survival, establishing GADD45A as an independent prognostic biomarker in this malignancy.

The investigators also mapped molecular pathways and immune cell infiltration using STRING, Gene Set Enrichment Analysis, and the TIMER2.0 analytical tool. These bioinformatic evaluations showed that low GADD45A expression was positively associated with an exhausted tumor immune microenvironment. This microenvironment was distinguished by elevated levels of key inhibitory immune checkpoints, including PDCD1, CTLA4, and LAG3, indicating that GADD45A expression serves as a clinically relevant indicator of the tumor immune landscape in liver hepatocellular carcinoma.

To confirm cell-intrinsic biological functions, researchers performed in vitro experiments in cultured human liver cancer cells. In modified HepG2 cells, assays evaluating cytotoxicity, qRT-PCR, Western blot, CCK-8 viability, colony formation, wound healing, and Transwell invasion demonstrated that GADD45A overexpression markedly suppressed cell proliferation, colony formation, and metastasis. In addition, GADD45A overexpression concurrently enhanced cancer cell chemosensitivity to cisplatin. These cellular outcomes were further complemented by Western blot and migration and invasion assays in Huh-7 cells, supporting the role of GADD45A as a significant cell-intrinsic tumor suppressor and a promising therapeutic target.

Subject of Research: GADD45A expression and tumor suppression in hepatocellular carcinoma

Article Title: Differential analysis of GADD45A expression in hepatocellular carcinoma: investigating its role and clinical implications through bioinformatics approaches

Article References: Xie, C., Wang, Z., Yuan, T., Zhang, Y., Fan, J., Jiang, F., Shi, L., Zheng, X., Ma, R., Ma, L., & Zhang, C. (2026). Differential analysis of GADD45A expression in hepatocellular carcinoma: investigating its role and clinical implications through bioinformatics approaches. Clinical and Experimental Medicine. https://doi.org/10.1007/s10238-026-02370-6

Image Credits: AI Generated

DOI: 10.1007/s10238-026-02370-6

Keywords: hepatocellular carcinoma, GADD45A, tumor suppressor, bioinformatics, immune checkpoints, cisplatin chemosensitivity, prognostic biomarker, Differential, analysis, expression, hepatocellular, carcinoma