Selective Effects of Fenbendazole on Normal Human Dermal Fibroblasts 2310154

Abstract Introduction Fenbendazole, a benzimidazole anthelmintic, has recently gained attention for its reported anticancer activity. This study aimed to evaluate the selectivity of fenbendazole by examining its effects on normal human dermal fibroblasts (HDFa), building on prior cancer cell line findings and emphasizing normal-cell response as a critical component of therapeutic relevance. Methods HDFa fibroblasts were cultured under standard mammalian cell culture conditions and maintained through routine passaging and cell counting. Fenbendazole exposure was conducted within available laboratory constraints, and cell viability trends were assessed using Trypan Blue exclusion assays and serial cell counts over time. Results HDFa fibroblasts were successfully maintained and consistently quantified throughout the study period. Under the exposure conditions tested, fenbendazole treatment resulted in minimal loss of fibroblast viability relative to previously observed cytotoxic effects in cancer cell lines. Literature findings supported the observed variability in fenbendazole response across cell types and suggested that resistance mechanisms and cellular context may influence drug sensitivity. Conclusion This continuation study strengthens the selectivity analysis of fenbendazole by prioritizing normal-cell response profiling. Preliminary findings suggest that fenbendazole exhibits reduced cytotoxic effects on normal fibroblasts under comparable exposure conditions, supporting a potentially favorable selectivity profile. Future work will focus on increased replicate testing and incorporation of marker-based validation assays as resources permit. Funding Source n/a Topic Categories Tumor Immunology: Cellular Responses and Tumor Microevironment (TIME)