Colon cancer (CC) is a common malignancy characterized by poor prognostic outcomes and considerable mortality. Oxaliplatin (OXP) is commonly used in the treatment of CC; however, its efficacy may be limited by side effects and the development of resistance. β-sitosterol (β-Sit), a phytosterol derived from plants, has been documented to be effective in the treatment of tumors. This study aimed to investigate the potential of β-Sit to enhance the antitumor efficacy of OXP in COLO-205 cells, focusing on apoptosis induction and suppression of the vascular endothelial growth factor A (VEGF-A)/survival pathway. Molecular docking studies were performed to assess the binding affinity of β-Sit with the target proteins B-cell lymphoma 2 (Bcl-2), phosphoinositide 3-kinase (PI3K), and VEGF receptor-2 (VEGFR-2). COLO-205 cells were treated with OXP, β-Sit, or a combination of OXP + β-Sit for 48 h. The combination treatment substantially lowered the IC₅₀ achieved with 3.24 µM of OXP and 36.01 µM of β-Sit, compared to 25.64 µM for OXP alone and 275.9 µM for β-Sit alone, demonstrating a pronounced synergistic impact. The combined therapy altered the cell cycle distribution by decreasing the number of cells in the G0/G, S, and G2/M phases, coupled with an increase in the Sub-G1 population. Furthermore, apoptosis was augmented by a shift in cell death from necrosis to late apoptosis, as indicated by an increased BAX/BCL2 ratio relative to each treatment alone. Moreover, the inhibitory effect on angiogenesis was enhanced via the reduction of VEGF-A, and β-catenin and nuclear factor κB (NF-κB-p65) were suppressed, thereby preventing the growth and survival of resistant cancer cells. Additionally, molecular docking supported high binding affinities of β-Sit to Bcl-2, PI3K, and VEGFR-2. This study highlights the potential of β-Sit to enhance the anti-cancer efficacy of OXP in CC.

Ethanol (EtOH)-induced gastric ulcer (GU) is a common model used to investigate mechanisms of mucosal injury and repair. Omeprazole (OMP) is a conventional anti-ulcer drug that effectively suppresses gastric acid secretion, but its efficacy may be enhanced by combining it with bioactive phytochemicals derived from a Glycyrrhiza glabra L. (licorice; LIQ) extract that possess potent antioxidant and anti-inflammatory properties. The aim of the present study was to evaluate the gastroprotective effects of OMP, LIQ extract, and their combined treatment against EtOH-induced GU in rats, focusing on modulation of TLR4/NF-κB/NLRP3 signaling and PI3K/AKT/mTOR gene expression. The ethanolic extract of LIQ was chemically characterized by LC-ESI-QTOF-MS/MS, and molecular docking was performed to evaluate the potential binding interactions of its major constituents with H⁺/K⁺-ATPase and COX-2. Thirty male Wistar rats were randomly allocated into control, ulcer (ULC), OMP-treated, LIQ-treated, and combined treatment groups. GU was induced by absolute EtOH. Subsequently, gastric pH, stomach coefficient, oxidative stress, inflammatory mediators, and PI3K, AKT, and mTOR gene expression were assessed. Histopathological and immunohistochemical analyses of mucosal architecture and the expression of TNF-α, caspase-3, and PCNA were performed. Coadministration of OMP and LIQ demonstrated the greatest gastroprotective activity, marked by a significant increase in gastric pH, restoration of antioxidant status, and substantial reduction in ROS, TLR4, NF-κB, and NLRP3 levels. The combined therapy significantly upregulated the expression of PI3K, AKT, and mTOR genes in comparison to ULC. Histopathological and immunohistochemical findings further demonstrated preservation of gastric mucosal integrity, reduced inflammatory cell infiltration, and decreased TNF-α, caspase-3, and PCNA immunoreactivity, indicating attenuation of mucosal injury. In conclusion, LIQ extract enhanced the gastroprotective effect of OMP against EtOH-induced GU, supporting its potential as an adjunct to OMP. Further studies are warranted to confirm the underlying molecular mechanisms.