The Cytotoxic Effects of Extracts of Different Solvents of Lonchocarpus Cyanescens' Stem Against Triple-Negative Breast Cancer (TNBC) Cell Lines

Lonchocarpus cyanescens, a plant widely used in traditional African medicine, has shown promise for cancer therapy. This study evaluates the cytotoxic effects of extracts from different solvents (n-hexane, ethyl acetate and methanol) from L. cyanescens against four triple-negative breast cancer cell lines (MCF7, MDA-MB-231, Hs578T, and SkBr3). Brine Shrimp Lethality Test (BSLT) was carried out as preliminary toxicity test and MTT assay for in vitro cytotoxicity against the four TNBC cell lines respectively. In the BSLT, methanol showed the highest toxicity (LC₅₀ = 51.19 µL), followed by A20E (LC₅₀ = 72.26 µL) and A10N (LC₅₀ = 81.27 µL), indicating that methanol highest concentration of cytotoxic bioactive compounds compared to the hexane and ethyl acetate extracts. The MTT assay further supported these findings, revealing that methanol extract had the lowest IC₅₀ values: 77 µM for MCF7, 69 µM for MDA-MB-231, and 71 µM for SkBr3, making it the most potent extract. In contrast, n-hexane extract, had IC₅₀ values >100 µg/mL across all cell lines, except for MDA-MB-231 where it has 97 µM while ethyl acetate exhibited moderate activity with an IC₅₀ of 87 µM against MDA-MB-231 and 71 µM against Hs578T respectively. These findings confirm the cytotoxic potential of L.C and highlight its prospective role in TNBC therapy. This study establishes a strong foundation for additional investigations into isolation and characterizing of active compounds from the crude extracts as well as mechanistic studies to determine its mode of action against breast cancer cells.