Near-infrared responsive 5-fluorouracil and indocyanine green loaded MPEG-PCL nanoparticle integrated with dissolvable microneedle for skin cancer therapy

The prevalence of skin cancer is rising along with the rapid population aging in recent years. Traditional therapies, such as surgical treatment, radiotherapy, chemotherapy, photodynamic therapy, and immunotherapy, may accompany serious side effects, limiting their clinical benefits. According to the biological characteristics of skin cancer, we have already established two kinds of synergetic systems of photothermal therapy (microneedle) and chemotherapy, containing gold nanorods (GNR). Although the microneedle system exhibited great potential for skin cancer treatment, the system could be still improved further. So, we designed a near-infrared light-responsive 5-fluorouracil (5-Fu) and indocyanine green (ICG) loaded monomethoxy-poly (ethylene glycol)-polycaprolactone (MPEG-PCL) nanoparticle (5-Fu-ICG-MPEG-PCL), and then 5-Fu-ICG-MPEG-PCL was integrated with a hyaluronic acid dissolvable microneedle system (HA MN) to get 5-Fu-ICG-MPEG-PCL loaded HA MN for treating skin cancers, including human epidermoid cancer and melanoma. In this system, hyaluronic acid, the microneedle carrier, possesses good skin penetration ability and is approved by FDA as a pharmaceutical adjuvant; 5-Fu is recommended by FDA for skin cancer treatment; ICG, a photothermal agent, possesses a strong photothermal ability and is approved by FDA for its use in the human body. We hypothesized that 5-Fu-ICG-MPEG-PCL could be delivered by the dissolvable microneedle through the skin, and the release behavior of the drug in the nanoparticle could be controlled by near-infrared light for achieving a single-dose cure of skin cancer, improving the cure rate of skin cancer and providing a new idea and possibility for the clinical treatment of skin cancer.