Transcriptome Analysis Reveals Possible Antitumor Mechanism of Intracellular Polysaccharide From <i>Phaeodactylum tricornutum</i> on Cervical Cancer HeLa Cells

Seaweed polysaccharide, a naturally occurring, non-toxic antitumor substance, has emerged as a significant focus of research. In this study, intracellular polysaccharides from Phaeodactylum tricornutum (PRP) were isolated and purified to investigate their antitumor effects and underlying mechanisms. The inhibitory effects of various purified polysaccharide fractions on cervical cancer cells were evaluated, and their antitumor mechanisms were elucidated through transcriptome analysis. The results demonstrated that all four purified polysaccharide fractions from P. tricornutum inhibited HeLa cell proliferation, reduced cell viability, and altered cell morphology. According to the cell counting kit-8 (CCK-8) assay, PRP4 exhibited the most potent inhibitory effect among the four fractions. Transcriptome analysis revealed 806 differentially expressed genes (DEGs) in the PRP4-treated group compared to the control, comprising 570 up-regulated and 236 down-regulated genes. Gene function enrichment analysis indicated that DEGs were significantly enriched in apoptosis- and tumor-related biological processes, implicating multiple cancer- and apoptosis-associated signaling pathways. A protein-protein interaction (PPI) network identified 10 DEGs as hub genes, namely TLR4, interleukin-1β (IL1B), heme oxygenase-1 (HMOX1), EDN1, PTGS2, MMP9, CXCL8, TGFB1, connective tissue growth factor (CTGF), and SERPINE1. These findings suggest that PRP4 holds promise as a therapeutic agent for cancer treatment.