Nanomedicines with high drug availability and drug sensitivity overcome hypoxia-associated drug resistance

Tumor hypoxia heterogeneity, a hallmark of the tumor microenvironment, confers resistance to conventional chemotherapy due to insufficient drug availability and drug sensitivity in hypoxic regions. To overcome these challenges, we develope a nanomedicine, NPHPaPN, constructed with hyaluronic acid (HA) grafted with cisplatin prodrug and PEG-azobenzene for hypoxia-responsive PEG shell deshielding and loaded with a DNA damage repair inhibitor (NERi). After arriving at the tumor site, NPHPaPN deshields the PEG shell in response to hypoxia due to the enzymolysis of azobenzene and thus exposes HA. The exposed HA binds to the highly expressed CD44 on cisplatin-resistant tumor cells and mediates drug internalization, thus increasing drug availability to hypoxic tumor cells. After intracellular hyaluronidase-mediated cleavage, the HA NPs release the cisplatin prodrug and NERi, and cause enhanced DNA damage and consequent cell death, thus enhancing the drug sensitivity of hypoxic tumor cells. Eventually, NPHPaPN achieves distinct tumor growth suppression with an similar to 84.4% inhibition rate.

Automated summary

Tumor hypoxia heterogeneity, a characteristic feature of the tumor microenvironment, leads to resistance to chemotherapy. To overcome this, a nanomedicine called NPHPaPN was developed, which utilizes hypoxia-responsive PEG shell deshielding and drug internalization through the HA-CD44 pathway to target cisplatin-resistant tumor cells. The release of cisplatin prodrug and a DNA damage repair inhibitor within the tumor cells enhances drug sensitivity and leads to significant tumor growth suppression with an inhibition rate of approximately 84.4%.