RhoF Promotes Snail1 Lactylation by Enhancing PKM2-Mediated Glycolysis to Induce Pancreatic Cancer Cell Endothelial–Mesenchymal Transition

Academic Background

Pancreatic cancer (PC) is a highly malignant tumor characterized by late diagnosis, strong invasiveness, and resistance to systemic therapy, leading to poor patient prognosis. Despite recent advancements in diagnostic and therapeutic techniques, the incidence and mortality rates of pancreatic cancer continue to rise. The mechanisms underlying pancreatic cancer invasion and metastasis remain unclear, making it crucial to delve deeper into its molecular mechanisms to develop more effective treatment strategies.

The Rho GTPase family plays a significant role in cell migration, proliferation, and metabolism. RhoF (Rho GTPase Rif), a member of the Rho GTPase family, is highly expressed in pancreatic cancer and is closely associated with tumor growth and epithelial-mesenchymal transition (EMT). However, the specific functional mechanisms of RhoF in pancreatic cancer have not been fully elucidated. Additionally, metabolic reprogramming is a hallmark of cancer cells, with glycolysis being significantly enhanced in pancreatic cancer cells, leading to the production of large amounts of lactate that promote tumor cell proliferation and metastasis. Therefore, investigating how RhoF regulates glycolysis and EMT to influence pancreatic cancer progression is of great importance.

Source of the Paper

This paper was co-authored by Rui Zhao, Yanmin Yi, Han Liu, Jianwei Xu, Shuhai Chen, Dong Wu, Lei Wang, and Feng Li from Qilu Hospital of Shandong University. The paper was published in 2024 in the journal Cancer & Metabolism, titled “RhoF Promotes Snail1 Lactylation by Enhancing PKM2-Mediated Glycolysis to Induce Pancreatic Cancer Cell Endothelial–Mesenchymal Transition.”

Research Process and Results

1. Expression of RhoF in Pancreatic Cancer and Its Relationship with Prognosis

The study first analyzed the expression of RhoF in pancreatic cancer tissues using the TCGA database, revealing that RhoF is significantly overexpressed in pancreatic cancer tissues. Kaplan-Meier survival analysis showed that patients with high RhoF expression had lower overall survival rates. Further experiments validated the high expression of RhoF in pancreatic cancer tissues and cells through qRT-PCR, immunohistochemistry (IHC), and Western blotting.

2. Effects of RhoF on Pancreatic Cancer Cell Growth and Apoptosis

The study assessed the impact of RhoF knockdown and overexpression on pancreatic cancer cell proliferation, apoptosis, migration, and invasion. The results showed that RhoF overexpression significantly promoted pancreatic cancer cell proliferation and migration while inhibiting apoptosis. Conversely, RhoF knockdown suppressed cell proliferation and migration and promoted apoptosis.

3. Regulation of EMT and Glycolysis in Pancreatic Cancer Cells by RhoF

The study found that RhoF overexpression downregulated the expression of the epithelial marker E-cadherin while upregulating the mesenchymal markers N-cadherin and Vimentin, indicating that RhoF promotes the EMT process. Additionally, RhoF overexpression significantly enhanced the expression of glycolysis-related proteins HK2, PKM2, and LDHA, increasing glucose uptake and lactate production.

4. RhoF Regulates PKM2 Transcription via c-Myc

Gene set enrichment analysis (GSEA) revealed that RhoF is positively correlated with c-Myc targets, EMT, and glycolysis. Further experiments demonstrated that RhoF promotes PKM2 transcription by upregulating c-Myc expression. The binding of c-Myc to the PKM2 promoter was validated through chromatin immunoprecipitation (ChIP) assays.

5. RhoF Induces Snail1 Lactylation via Glycolysis to Promote EMT

The study further explored how RhoF promotes Snail1 lactylation through glycolysis-derived lactate, thereby inducing EMT. Experimental results showed that RhoF overexpression promoted Snail1 lactylation and nuclear translocation, while RhoF knockdown inhibited this process. Moreover, the glycolysis inhibitor 2-DG reversed the promoting effects of RhoF on Snail1 lactylation.

6. In Vivo Validation of RhoF’s Role

By constructing a pancreatic cancer xenograft mouse model, the study validated the role of RhoF in vivo. The results showed that RhoF knockdown significantly inhibited tumor growth and the EMT process while reducing the number of Ki67-positive cells and increasing the proportion of apoptotic cells.

Conclusion and Significance

This study found that RhoF plays an oncogenic role in pancreatic cancer by upregulating c-Myc expression, promoting PKM2 transcription, and inducing glycolysis. The lactate produced by glycolysis leads to Snail1 lactylation, ultimately promoting the EMT process. This research reveals a new molecular mechanism of RhoF in pancreatic cancer and provides a potential therapeutic target for pancreatic cancer treatment.

Research Highlights

1. High expression of RhoF is associated with poor prognosis in pancreatic cancer patients, offering a new biomarker for pancreatic cancer prognosis assessment.
2. RhoF regulates EMT through the c-Myc-PKM2-glycolysis-Snail1 lactylation axis, highlighting the critical role of RhoF in pancreatic cancer metastasis.
3. The glycolysis inhibitor 2-DG reverses the promoting effects of RhoF on Snail1 lactylation, providing new insights for pancreatic cancer treatment.

Other Valuable Information

This study also systematically validated the functional mechanisms of RhoF in pancreatic cancer through bioinformatics analysis and various experimental methods (e.g., qRT-PCR, Western blotting, ChIP, immunofluorescence), providing a wealth of data support for subsequent research.

This research not only uncovers the new mechanisms of RhoF in pancreatic cancer but also offers a theoretical basis for developing therapeutic strategies targeting RhoF and its downstream signaling pathways.