Background::Cancer Stem Cells (CSCs) play an important role in various stages of cancer development,
advancement, and therapy resistance. Ketoprofen-RGD has been revealed to act as an anti-cancer agent
against some tumors.
Objective::We aimed to explore the effects of a novel Ketoprofen-RGD compound on the suppression of Breast
Cancer Stem-like Cells (BCSCs) and their parental cells.
Methods::Mammospheres were developed from MCF-7 cells and assessed by CSC surface markers through
flowcytometry. The anti-proliferative and pro-apoptotic activities of Ketoprofen-RGD were measured by MTS
assay and flowcytometry. The expression levels of stemness markers and JAK2/STAT proteins were measured by
quantitative Real Time-PCR (qRT-PCR) and western blotting, respectively. Intracellular Reactive Oxygen Species
(ROS) was measured using a cell permeable, oxidant-sensitive fluorescence probe (carboxy-H2DCFDA).
Results::Ketoprofen-RGD significantly reduced the mammosphere formation rate and the expression of three
out of six stemness markers and remarkably decreased viability and induced apoptosis of spheroidal and parental
cells compared to controls. Further experiments using CD95L, as a death ligand, and ZB4 antibody, as an
extrinsic apoptotic pathway blocker, showed that Ketoprofen-RGD induced intrinsic pathway, suggesting a
mechanism by which Ketoprofen-RGD triggers apoptosis. ROS production was also another way to induce
apoptosis. Results of western blot analysis also revealed a marked diminish in the phosphorylation of JAK2 and
STAT proteins.
Conclusion::: Our study, for the first time, elucidated an anti-BCSC activity for Ketoprofen-RGD via declining
stemness markers, inducing toxicity, and apoptosis in these cells and parental cells. These findings may suggest
this compound as a promising anti-breast cancer.