NGF and neuroblastoma: Sea cucumbers (NDEELNK [109], FETLMPLWGNK [110], HEPFYGNEGALR [110], and KMYPVPLN [110]) have been reported to exhibit neuroprotective effects by improving the cholinergic system, increasing energy metabolism, upregulating the expression of phosphorylated protein kinase A (p-PKA), brain-derived neurotrophic factor (BNDF), and nerve growth factor (NGF) signaling proteins in PC12 cells (for NDEELNK), alleviating oxidative stress in neuroblastoma cells, and improving survival in C. elegans exposed to neurotoxic paraquat (for FETLMPLWGNK, HEPFYGNEGALR, and KMYPVPLN).