Lunasin is a plant-derived peptide with moderate anticancer activity but has limited potency and undefined molecular targets. To enhance its functional properties, we developed a site-specifically acetylated variant (Lunasin-K29ac) via genetic code expansion. To characterize the molecular interactions underlying its enhanced activity, we performed interactome profiling of a control (pET-22b-CBD), wild-type Lunasin, and Lunasin-K29ac in HT-29 cells using His pull-down MS.