ROLE OF THEAFLAVIN-DERIVED TITANIUM NANOPARTICLE IN MODULATING EGF SIGNALLING IN KB CELLS

Background: Oral squamous cell carcinoma (OSCC) is a prevalent and highly invasive malignancy marked by alterations in cellular communication networks such as EGFR/AKT, which drive uncontrolled cell growth and resistance to cell death. Natural polyphenols, such as theaflavin, possess anticancer properties; however, their therapeutic potential is limited by poor bioavailability. Nanotechnology offers a promising platform to enhance delivery and efficacy. This study investigates the effect of Theaflavin-Derived Titanium Nanoparticles (Thef-TiNPs) on EGF signalling and apoptosis-related gene expression in KB cells. Objective: To evaluate the cytotoxic, antioxidant, and gene regulatory effects of Thef-TiNPs on human oral cancer KB cells, focusing on modulation of EGFR, AKT1, BAX, BCL-2, CASPASE-3, and HSP70 gene expression. Methods: The Thef-TiNPs were prepared through a green sol-gel process and characterised by SEM, FTIR, and XRD. Cytotoxicity was determined using the MTT assay at concentrations ranging from 1 to 100 µg/mL. The antioxidant potential was evaluated using the widely applied DPPH radical scavenging assay, which measures the capacity to neutralize free radicals.KB cells were exposed to Thef-TiNPs and subsequently, alterations in the cell morphology were monitored using microscopy. Gene expression profiling was conducted with quantified real-time PCR, focusing on key components of the EGFR signalling cascade and markers indicative of apoptosis. Results: Thef-TiNPs exhibited dose-dependent cytotoxicity, with significantly higher activity than theaflavin or titanium alone, achieving ~98% cell death at 100 µg/mL. Antioxidant activity was also superior, with DPPH scavenging nearing that of the positive control at high doses. Morphological analysis confirmed concentrationdependent cellular damage. Gene expression results showed downregulation of EGFR (0.38-fold), AKT1 (0.42-fold), BCL-2 (0.46-fold), and HSP70 (0.49-fold), while BAX (2.71-fold) and CASPASE-3 (2.23-fold) were significantly upregulated, indicating strong pro-apoptotic and anti-survival effects. Conclusion: Thef-TiNPs effectively inhibit EGFR/AKT signalling and induce apoptosis in KB cells through modulation of critical molecular targets. Collectively, these results indicate that the nano-formulated therapy holds promise as an enhanced oral cancer treatment, demonstrating superior therapeutic effects compared to its individual components.