Photosensitizer-loaded gold nanocages for immunogenic phototherapy of aggressive melanoma.

Malignant melanoma remains the life-threatening form of skin cancer with high mortality and poor prognosis. Thus, an ideal melanoma therapeutic strategy is of immediate importance which can remove the primary tumor, as well as inhibit the metastasis and recurrence. Here, we report the fabrication of adjuvant monophosphoryl lipid A (MPLA) lipid bilayer-enveloped and photosensitizer indocyanine green (ICG)-loaded gold nanocages (MLI-AuNCs) for immunogenic phototherapy of aggressive melanoma. Hollow porous AuNCs are used as carriers to deliver MPLA and ICG, and protect ICG from photodegradation. Both AuNCs and ICG absorb near infrared (NIR) light and can be applied in controllable NIR-triggered photothermal and photodynamic combination therapy (PTT/PDT) of melanoma. MLI-AuNCs coated by thermosensitive lipid bilayer exhibit uniform size, good biocompatibility and bioavailability with prominent tumor accumulation, which further improve the PTT/PDT efficacy. MLI-AuNCs under NIR irradiation not only destroy the primary tumor by PTT/PDT, but also elicit robust antitumor immune response with melanoma associated antigens and MPLA released in situ. The released antigens and MPLA subsequently enhance the recruitment and maturation of dendritic cells, which further activate the effector T cells to inhibit metastases and recurrence of melanoma. This immunomodulatory-boosted PTT/PDT nanoplatform provides a new opportunity for highly aggressive melanoma treatment. STATEMENT OF SIGNIFICANCE: An ideal tumor therapeutic strategy not only can remove the primary tumor, but also inhibit metastasis and recurrence. Here, we introduced a versatile nanoplatform MLI-AuNCs for immunogenic phototherapy of aggressive melanoma. Adjuvant MPLA and photosensitizer ICG can be protected and co-delivered to the tumors by thermosensitive lipid-enveloped AuNCs. MLI-AuNCs exhibited prominent tumor accumulation ability and produced the potent PTT/PDT effect to destroy the primary tumors with a single dose of NIR irradiation, as well as elicited the strong antitumor immunity to inhibit the metastasis and relapse. This study may provide a potential therapeutic vaccination strategy against advanced melanoma and other difficult-to-treat cancers.

Au Nanocage-Strengthened Dissolving Microneedles for Chemo-Photothermal Combined Therapy of Superficial Skin Tumors.

For superficial skin tumors (SST) with high incidence, surgery and systemic therapy are relatively invasive and possible to cause severe side effect, respectively. Yet, topical therapy is confronted with the limited transdermal capacity because of the stratum corneum barrier layer of skin. Therefore, it is crucial to develop a highly effective and minimally invasive alternative transdermal approach for treating SST. Here, we developed gold nanocage (AuNC)- and chemotherapeutic drug doxorubicin (DOX)-loaded hyaluronic acid dissolving microneedle (MN) arrays. The loaded AuNCs are not only reinforcers to enhance the mechanical strength of the MNs, but also effective agents for photothermal therapy to obtain effective transdermal therapy for SST. The resultant MNs can effectively penetrate the skin, dissolve in the skin and release cargoes within the tumor site. Photothermal effect of AuNCs initiated by near-infrared laser irradiation combined with the chemotherapy effect of DOX destroyed tumors synergistically. Moreover, we verified the potent antitumor effects of the DOX/AuNC-loaded MNs after four administrations to SST-bearing mice without obvious side effects. Therefore, the drug/AuNC-loaded dissolving MN system provides a promising platform for effective, safe, minimally invasive combined treatment of SST.

Skin healing and collagen changes of rats after fractional erbium:yttrium aluminum garnet laser: observation by reflectance confocal microscopy with confirmed histological evidence.

The fractional erbium:yttrium aluminum garnet (Er:YAG) laser is widely applied. Microstructural changes after laser treatment have been observed with histopathology. Epidermal and dermal microstructures have also been analyzed using reflectance confocal microscopy (RCM). However, no studies have compared these two types of microstructural changes in the same subject at multiple time points after irradiation, and it is unclear if these two types of changes are consistent. We use RCM to observe the effect of different laser energies on skin healing and collagen changes in the skin of Sprague-Dawley rats that had been irradiated by fractional Er:YAG lasering at different energies. RCM was used to observe skin healing and detect collagen changes at different time points. Collagen changes were observed using hematoxylin and eosin (H&E) staining and quantitatively analyzed by western blot. RCM showed that, irrespective of laser energy, microscopic treatment zones (MTZs) were larger at 1 day after irradiation. The MTZs then reduced in size from 3 to 7 days after irradiation. The higher the energy, the larger the MTZ area. The amount of collagen also increased with time from 1 day to 8 weeks. However, the increase in the collagen amount on both RCM and H&E staining was not influenced by the laser energy. Western blotting confirmed that the amount of type I and type III collagens increased over time, but there were no significant differences between the different energy groups (p > 0.05). In conclusion, RCM is a reliable technique for observing and evaluating skin healing and collagen expression after laser irradiation.