KRAS and breast carcinoma: Overall, potent therapeutic efficacy against breast cancer in mice was achieved due to effective intratumor and intracellular delivery of let‐7a with CNPs, as well as a synergistic effect between let‐7a and the chemotherapeutic, PTX, because the downregulation of KRAS protein by let‐7a enabled cancer cell sensitization to the chemotherapeutic agents.24