TRPV4 as a Novel Regulator of Ferroptosis in Colon Adenocarcinoma: Implications for Prognosis and Therapeutic Targeting.

Abstract

Background: Colon adenocarcinoma (COAD) is a leading cause of cancer-related mortality worldwide. Transient receptor potential vanilloid 4 (TRPV4), a calcium-permeable non-selective cation channel, has been implicated in various cancers, including COAD. This study investigates the role of TRPV4 in colon adenocarcinoma and elucidates its potential mechanism via the ferroptosis pathway.

Materials and methods: Gene expression profiles and clinical data were obtained from The Cancer Genome Atlas (TCGA), encompassing 647 colon adenocarcinoma tissue samples and 51 normal colorectal tissue samples. Ferroptosis-related genes were retrieved from the FerrDb database. Differential expression analysis, survival analysis, and Cox proportional hazards regression were performed to assess the prognostic significance of TRPV4. Protein-protein interaction networks and gene enrichment analyses (GO and KEGG) were conducted to explore functional associations. In vitro experiments were carried out using HT-29 and SW480 colon cancer cell lines. TRPV4 was knocked down using siRNA, and cell viability was assessed via hematoxylin and eosin (HE) staining. Immunofluorescence assays evaluated the expression of ferroptosis-related proteins (SLC3A2, GPX4) and proliferation markers (KI67, SRC, CTNNB1, COL1).

Results: TRPV4 expression was significantly elevated in colon adenocarcinoma tissues compared to normal tissues (p < 0.05), demonstrating high diagnostic accuracy (AUC = 0.848). High TRPV4 expression correlated with poorer overall survival (OS) and disease-specific survival (DSS), particularly in patients over 65 years old and those in clinical stage II. Cox regression analysis confirmed TRPV4 as an independent prognostic factor (HR = 1.395, p = 0.074). Bioinformatics analyses revealed that TRPV4 is closely associated with ferroptosis-related genes, participating in key biological processes such as responses to external stimuli, oxidative stress, and cell adhesion. In vitro, TRPV4 knockdown significantly reduced cell viability (p < 0.05) and decreased expression levels of SLC3A2, GPX4, KI67, SRC, and COL1 (p < 0.05). The addition of the ferroptosis inhibitor FER-1 did not restore cell viability in TRPV4 knockdown cells, suggesting that TRPV4 modulates cell survival through the ferroptosis pathway.

Discussion: The bioinformation and in vitro experiments inTRPV4 and ferroptosis-related genes support the hypothesis that TRPV4 influences tumor cell survival via the ferroptosis pathway. The inability of FER-1 to rescue viability in TRPV4-deficient cells further confirms this mechanism. These findings provide novel insights into the molecular mechanisms of COAD and highlight TRPV4 as a potential therapeutic target.

Conclusion: TRPV4 is significantly upregulated in COAD and is associated with unfavorable patient outcomes. It appears to promote tumor progression by regulating the ferroptosis pathway, affecting the expression of key ferroptosis-related genes and proliferation markers. Targeting TRPV4 may offer a new therapeutic approach for COAD, and further research is warranted to explore its role in other cancers and to develop TRPV4-based therapies.