Antitumor potential of inorganic nanoparticles vs. bee venom combined with immunotherapy

Abstract Inorganic nanoparticles and bee venom are emerging anticancer agents with potential for tumor‑selective cytotoxicity and immune modulation. This study aimed to compare the anticancer activity of three inorganic nanoparticle formulations (Cu‑2.5 nm, Ag‑Citrate‑5 nm, and Fe‑ZnO) and crude bee venom across cancer cell lines representing breast (E0771, MDA-MB, 4T1), pancreatic (Panc-1, KPC), colorectal (CT26), renal (Renca), melanoma (B16-F10) and cervical (HeLa) models, and to assess bee venom’s therapeutic effects in vivo. Standardized viability assays were used to evaluate cytotoxicity, and a KPC pancreatic cancer mouse model was employed for in vivo validation. Cu‑2.5 nm nanoparticles showed the strongest cytotoxicity, while Ag‑Citrate‑5 nm and Fe‑ZnO exhibited variable, formulation‑dependent activity. Crude bee venom demonstrated broad and selective cytotoxicity across most cancer cell lines, outperforming melittin in several models and sparing healthy cells. Panc‑1 and B16‑F10 were less sensitive but responded at higher concentrations. In vivo, crude bee venom significantly inhibited tumor growth, and combination therapy with anti‑PDL1 and epacadostat further enhanced tumor suppression and increased CD4⁺/CD8⁺ T‑cell recruitment and activation, indicating synergistic immunomodulatory effects. These findings highlight crude bee venom as a dual‑acting anticancer candidate with both direct cytotoxic and immune‑enhancing properties, supporting its continued preclinical development in combination therapy strategies.