Exploratory transcriptomics and in vivo analyses of suramin in tongue squamous cell carcinoma.

Suramin, an anti-trypanosomal agent, has gained attention for its potential anticancer activity, partly through the modulation of RNA-binding proteins such as HuR. However, its genome-wide transcriptomic effects in oral squamous cell carcinoma remain unclear. In the present study, RNA-sequencing was performed on suramin-treated HSC-3 cells, followed by enrichment, network and transcription factor analyses. In vivo validation was conducted in an orthotopic xenograft model using luciferase-labeled HSC-3 cells. Suramin was administered intraperitoneally at a dose of 20 mg/kg, twice weekly. Transcriptomic profiling revealed broad downregulation of genes governing cell cycle progression, chromatin organization and DNA damage response, including mitotic regulators such as G2/M regulators CCNB1, CDC20 and AURKA, and their upstream transcription factors FOXM1 and MYBL2. By contrast, genes associated with extracellular matrix remodeling (the MMP family and TIMP3) and stress or immune responses (TXNIP and TNFSF10) were upregulated. Functional enrichment confirmed the suppression of proliferative programs with the concurrent activation of tumor-suppressive microenvironmental responses. In vivo, suramin-treated mice exhibited lower tumor growth compared with that in the control group, although the difference was not statistically significant (P=0.18). Effect size estimates were relatively large for both the group effect (partial η2=0.20) and the time x group interaction (partial η2=0.24), suggesting that the study may have been underpowered to detect this difference statistically. In conclusion, the present exploratory study suggests that suramin exerts a dual antitumor effect on tongue squamous cell carcinoma by suppressing proliferative transcriptional programs, and modulating extracellular and stress response pathways, providing a basis for future studies to further elucidate its therapeutic relevance.