Enhanced transdermal lymphatic delivery of doxorubicin via hyaluronic acid based transfersomes/microneedle complex for tumor metastasis therapy.

Tumor-draining lymph nodes (TDLN) are major metastatic sites for many solid tumor to support tumor progression and metastasis. Lymphatic delivery is regarded as a desirable route to promote adoptive immune response via vaccination, or to achieve efficient chemotherapy for tumor metastasis. In this study, a novel dissolving microneedle was fabricated using hyaluronic acid, integrated with transfersome (T) to break the limit of transdermal cargo transit. In virtue of the insertion capacity of microneedle and the lymphatic delivering ability of transfersomes, such transfersome/microneedles complex (T/MNs) was expected to enhance lymphatic delivery. The results revealed that the microneedles were able to efficiently insert into rat skin and release the doxorubicin loaded transfersome (DOX-T) in dermis via self-dissolution. DOX-T would maintain their multilayer structure as released from dissolved microneedles. DOX-T/MN could significantly promote accumulation of DOX in lymph nodes compared to epidermal diffusion, and increased its transdermal bioavailability in plasma. The results not only are promising for chemo-therapy of tumor through lymphatic drug delivery, especially for killing the metastasized tumor cells appeared in draining lymph nodes, they also provide an efficient strategy for tumor immune-therapy using transdermal administration.