In 2017, frondoside A (compound 53, Figure 16) was isolated from Cucumaria frondosa, the Atlantic sea cucumber, and reported as being an effective inhibitor of PAK1 (IC50 ~ 1.2 μM), LIMK (IC50 ~ 60 μM), AKT (IC50 ~ 59 μM) and A549 lung cancer cells (IC50 ~ 1–3 μM) in vitro, indicating that it may be useful in the treatment of malignancies [64,65]. Here, AKT1 is linked to lung cancer.