Haifei Chen

The Warburg effect, which is aerobic glycolysis, constitutes a major driver of various cancer progression. Therefore, we aimed to examine the role of peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC1α) and its competing endogenous RNA (ceRNA) network in colorectal cancer (CRC) metabolic reprogramming. We used bioinformatics analysis and dual-luciferase reporter gene experiments and identified the DNMBP-AS1/hsa-miR-30a-5p/PGC1α ceRNA network. Additionally, we investigate the impact of PGC1α expression alterations on CRC proliferation and metabolic reprogramming. Moreover, we studied the influence of PGC1α on pyruvate kinase M2 (PKM2), and CRC malignant behavior manifestation. Our study has uncovered a significant association between the DNMBP-AS1/hsa-miR-30a-5p/PGC1α ceRNA network and CRC patient prognosis. Additionally, PGC1α overexpression impeded CRC growth, reduced glycolytic capacity, and enhanced anti-PD-1 therapy efficacy. PGC1α inhibited tumor cell glycolysis by downregulating the WNT/β-catenin pathway depending on peroxisome proliferator-activated receptor gamma (PPARγ), thereby suppressing PKM2. The PPARγ agonist rosiglitazone could hinder CRC proliferation and glycolytic activity. Combined with the PGC1α agonist ZLN005, it exhibits synergistic effects for treating CRC. Moreover, we verified that ZLN005 significantly potentiated PD-1 induced tumor suppression in xenograft mice. Finally, we demonstrated that PGC1α and PKM2 expression patterns in tumor tissues were closely related to patient prognosis. Moreover, we constructed a predictive model to predict the 5-year survival events in CRC patients using random forest model. Our results offer novel perspectives on the role of DNMBP-AS1/hsa-miR-30a-5p/PGC1α network in controlling CRC proliferation, metabolism and immune responses. Furthermore, our investigation reveals that using rosiglitazone combined with PGC1α agonist presents a promising therapeutic approach for managing CRC.

The nuclear receptor Nur77 plays paradoxical roles in numerous cancers. However, whether Nur77 inhibits esophageal squamous cell carcinoma (ESCC) growth and affects immunological responses against ESCC has not been determined. The functional role of Nur77 in ESCC was investigated in this study using human ESCC cell lines, quantitative real-time polymerase chain reaction (PCR), cell proliferation and colony formation assays, flow cytometry analysis, western blotting and animal models. The target gene controlled by Nur77 was verified using dual-luciferase reporter assays, chromatin immunoprecipitation analysis and functional rescue experiments. To examine the clinical importance of Nur77, 72 human primary ESCC tissues were subjected to immunohistochemistry. Taken together, these findings showed that, both in vitro and in vivo, Nur77 dramatically reduced ESCC cell growth and triggered apoptosis. Nur77 directly interacts with the interferon regulatory factor 1 (IRF1) promoter to inhibit its activity in ESCC. Pharmacological induction of Nur77 using cytosporone B (CsnB) inhibited ESCC cell proliferation and promoted apoptosis both in vitro and in vivo. Furthermore, CsnB increased CD8+ T-cell infiltration and cytotoxicity to inhibit the formation of ESCC tumors in an immunocompetent mouse model. In ESCC tissues, Nur77 expression was downregulated, and IRF1 expression was increased; moreover, their expression levels were negatively related. IRF1 and Nur77 were strongly correlated with overall survival. These findings suggested that Nur77 targets and regulates the IRF1/PD-L1 axis to serve as a tumor suppressor in ESCC.

Background: Glycolysis under normoxic conditions, known as the Warburg effect, confers a selective advantage for the survival and proliferation of many tumors. In this study, we investigated the role of estrogen-related receptor gamma (ESRRG) in metabolic reprogramming in esophageal squamous cell carcinoma (ESCC). Methods: Bioinformatics analysis indicated that ESRRG expression was decreased in ESCC tissue and associated with poor clinical outcomes. We also examined the effects of altered ESRRG expression on the proliferation and metabolic reprogramming of ESCC cells. We explored the impact of ESRRG on Pyruvate kinase M2 (PKM2) expression and malignant behavior in ESCC. Results: Our study revealed the inhibitory effects of ESRRG on the growth, tumorigenesis, and glycolysis activity of ESCC cells, which were mediated by the downregulation of PKM2 expression. We further demonstrated that ESRRG directly interacts with the PKM2 promoter to inhibit its activity in ESCC. Notably, the ESRRG-specific agonist, DY131, inhibited ESCC cell proliferation and glycolysis activity by modulating genes in the glycolysis pathway. Moreover, we verified that DY131 exhibits enhanced activity as an immune checkpoint inhibitor, considering the significance of the ESRRG-PKM2 axis in the lactate regulation of ESCC cells. Conclusion: Our findings provide novel insights into the role of ESRRG-PKM2 signaling in regulating ESCC cell metabolism and immune checkpoint regulation. Additionally, we suggest that DY131 holds promise as a promising therapeutic agent for ESCC treatment.