Breast cancer targeting peptide 18–4

Breastcancertargeting peptide 18–4 is a keratin 1 (KRT1) receptor-targeting peptide with a dissociation constant (Kd) of 0.98 μM. Its amino acid sequence is WxEAAYQrFL, and it is an analogue of the P160 peptide. When covalently bonded with the anticancer peptide MccJ25, it significantly enhances MccJ25 uptake in breast cancer cells and boosts its anticancer efficacy. The IC50 values for this covalent compound are 14.2, 20, and 25 μM against MCF-7, MDA-MB-435, and MDA-MB-435-MDR, respectively.

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