PEGylated Liposomes Accumulate in the Areas Relevant to Skin Toxicities via Passive Extravasation across "Leaky" Endothelium

PEGylated liposome is the cornerstone platform for modern drug delivery. Unfortunately, as exemplified by PEGylated liposomal doxorubicin (aka Doxil), altered doxorubicin pharmacokinetics causes off-target accumulation in the skin, including the palms and feet, leading to severe dose-limiting toxicity. In addition to Doxil, other nanoparticles and PEGylated liposomes exhibit significant deposition in the skin, but mechanisms of accumulation are poorly understood. Using ex vivo imaging and ex vivo confocal microscopy, we show that PEGylated liposomes in mice accumulate predominantly in the areas subject to mechanical stress/pressure. Blood vessels in foot skin appear to be especially leaky, exhibiting burst-like extravasations. Using high-resolution confocal microscopy and liposomes labeled with different dyes in the membrane and/or interior, two modes of extravasation were observed: (1) as intact liposomes; (2) as separated liposomal components. On the other hand, stable cross-linked iron oxide nanoworms extravasated only as intact nanoparticles. There was no colocalization between liposomes and exosomal marker CD81, excluding the role of exocytosis. Also, in situ perfusion of formalin-fixed foot skin with labeled liposomes revealed that the extravasation is mediated by passive, energy-independent diffusion and not by leukocyte "hitchhiking". These findings improve our understanding of extravasation pathways of nanocarriers in the areas relevant to skin pathologies and could lead to strategies to prevent and treat liposome-induced skin toxicities.

Multikinase Inhibitor-Induced Hand-Foot Skin Reaction: A Review of Clinical Presentation, Pathogenesis, and Management

Multikinase inhibitors (MKIs) are targeted cancer therapies designed to inhibit multiple tyrosine kinase pathways responsible for tumor proliferation, growth, and survival. These agents are more able to target cancer cells and possess better safety profiles than conventional chemotherapies. However, MKIs can produce significant cutaneous adverse events, hand-foot skin reaction (HFSR) being the most clinically significant. Although not life threatening, HFSR can lead to MKI dose modification, interruption, or termination, potentially limiting the anti-tumor effect. This article summarizes the current knowledge concerning the epidemiology, clinical presentation, pathogenesis, histopathology, prognostic implication, and current evidence-based prophylactic and reactive treatment options for MKI-induced HFSR. Its high incidence and significant impact on the quality of life emphasizes the great need to understand the pathogenesis and improve management of this condition.

Chemotherapy-induced hand-foot syndrome and nail changes: a review of clinical presentation, etiology, pathogenesis, and management

Chemotherapy-induced hand-foot syndrome and nail changes are common complications of many classic chemotherapeutic agents and the newer molecular targeted therapies. They significantly impact patient quality of life, and frequently necessitate chemotherapy dose intensity modification or reduction. We aim to describe the epidemiology, pathogenesis, clinical presentation, and current evidence-based treatment options for these entities.

Prevention strategies for chemotherapy-induced hand-foot syndrome: a systematic review and meta-analysis of prospective randomised trials

PURPOSE

Hand-foot syndrome (HSF) is a distinctive adverse event relatively frequent to some chemotherapeutic agents as capecitabine, pegylated liposomal doxorubicin, sorafenib and other tyrosine-kinase inhibitors. Since the prevention of HFS would be crucial to avoid treatment interruptions and delays, many studies have been conducted with this purpose.

METHODS

The aim of this systematic review and meta-analysis was to analyze the clinical efficacy of prevention strategies for HFS, through a wide search of electronic databases as well as congress abstracts. The endpoints evaluated were the dichotomic data for mild (Grade 1), moderate to severe (Grades 2 to 3) and all-grade HFS. Meta-analysis was calculated through RevMan v5.1 software.

RESULTS

Amongst 295 studies identified, only ten met the inclusion criteria. Celecoxib prevented both moderate to severe (odds ratio [OR] 0.39, 95 % confidence interval [CI] 0.20-0.73, P = 0.003) and all-grade HFS (OR 0.47, 95 % CI 0.29-0.78, P = 0.003), whereas pyridoxine and topical urea/lactic acid formulations failed to prove efficacy. There were no proven benefits in mild HFS. The use of topical antiperspirant has not been shown to improve results, according to a single trial.

CONCLUSIONS

From all available possibilities for the prevention of HFS, celecoxib appears to be the most promising, with statistically significant results. Larger, multicentric studies are required to reinforce this finding.