A novel 2-pyrone derivative, BHP, impedes oncogenic KRAS-driven malignant progression in breast cancer

•KRAS promotes invasion through epithelial-mesenchymal transition in breast cancer.•KRAS contributes resistance of breast cancer to radio- and chemo-therapy.•BHP blocks KRAS-induced malignant phenotypes in breast cancer.•BHP inhibits the downstream effectors of KRAS signaling, PI3K/AKT and Raf-1/ERK.

Elevated KRAS expression has been frequently associated with cancer progression including breast cancer; however, therapeutic approaches targeting KRAS have been widely unsuccessful and KRAS mutant cancers remain unsolved problem in cancer therapy. In this study, we found that a new 2-pyrone derivative, 5-bromo-3-(3-hydroxyprop-1-ynyl)-2H-pyran-2-one (BHP) can block KRAS-driven breast cancer progression. Importantly, treatment with BHP effectively suppressed the migratory and invasive properties along with epithelial–mesenchymal transition (EMT) in MDA-MB231 breast cancer cells that carry oncogenic KRAS and mesenchymal malignant phenotypes. In parallel, BHP also sensitized the cells to anticancer treatment. Consistently, forced-expression of oncogenic KRAS bestowed the migratory and invasive properties, mesenchymal transition and resistance to anticancer treatment into normal human mammalian breast cells MCF10A and relatively non-malignant MCF7 and SK-BR3 breast cancer cells; however, treatment with BHP blocked those KRAS-induced malignant phenotypes. Notably, BHP interfered the interaction of KRAS with Raf-1 in concentration-dependent manner, thereby blocking the downstream effectors of KRAS signaling that is PI3K/AKT and ERK. Taken together, our findings indicate that the BHP, an α-pyrone derivative, suppresses malignant breast cancer progression by targeting of oncogenic KRAS signaling pathways.