“Background: Conventional dissolving microneedles (DMNs) face significant challenges in anti-melanoma therapy due to the lack of active thrust to achieve efficient transdermal drug delivery and intra-tumoral penetration.
Methods: In this study, the effervescent cannabidiol solid dispersion-doped dissolving microneedles (Ef/CBD-SD@DMNs) composed of the combined effervescent components (CaCO3 & NaHCO3) and CBD-based solid dispersion (CBD-SD) were facilely fabricated by the “one-step micro-molding” method for boosted transdermal and tumoral delivery of cannabidiol (CBD).
Results: Upon pressing into the skin, Ef/CBD-SD@DMNs rapidly produce CO2 bubbles through proton elimination, significantly enhancing the skin permeation and tumoral penetration of CBD. Once reaching the tumors, Ef/CBD-SD@DMNs can activate transient receptor potential vanilloid 1 (TRPV1) to increase Ca2+ influx and inhibit the downstream NFATc1-ATF3 signal to induce cell apoptosis. Additionally, Ef/CBD-SD@DMNs raise intra-tumoral pH environment to trigger the engineering of the tumor microenvironment (TME), including the M1 polarization of tumor-associated macrophages (TAMs) and increase of T cells infiltration. The introduction of Ca2+ can not only amplify the effervescent effect but also provide sufficient Ca2+ with CBD to potentiate the anti-melanoma efficacy. Such a “one stone, two birds” strategy combines the advantages of effervescent effects on transdermal delivery and TME regulation, creating favorable therapeutic conditions for CBD to obtain stronger inhibition of melanoma growth in vitro and in vivo.
Conclusions: This study holds promising potential in the transdermal delivery of CBD for melanoma therapy and offers a facile tool for transdermal therapies of skin tumors.”
“In summary, the novel Ef/CBD-SD@DMNs system developed in this study offers a promising approach to improve the efficacy of CBD-based therapy for melanoma. Ef/CBD-SD@DMNs combines the advantages of effervescence and CBD-based solid dispersion to achieve better transdermal and tumoral delivery of CBD. The in vitro and in vivo results demonstrate that Ef/CBD-SD@DMNs can not only effectively induce melanoma apoptosis via the “Ca2+ influx-NFATc1-ATF3” pathway but also activate the tumor microenvironment probably through increasing intra-tumoral pH environment. This study provides a facile and efficient design for a transdermal delivery system that may have a significant impact on the development of new melanoma therapies.”