Transpapillary (Nipple) Delivery of Macromolecules to the Breast: Proof of Concept Study

Co-delivery of lapatinib and 5-fluorouracil transfersomes using transpapillary iontophoresis for breast cancer therapy

Combination chemotherapy, involving the intervention of two or more anti-neoplastic agents has been the cornerstone in breast cancer treatment, owing to the applications it holds in contrast to the mono-therapy approach. This research predominantly focussed on proving the synergy between Lapatinib (LPT) and 5-Fluorouracil (5-FU) and further enhancing its localized permeation via transfersome-loaded delivery and iontophoresis to treat breast tumors. The IC50 values for LPT and 5-FU were found to be 19.38 µg/ml and 5.7 µg/ml respectively and their synergistic effect was proven by the Chou-Talalay assay using CompuSyn software. Furthermore, LPT and 5-FU were encapsulated within transfersomes and administered via the transpapillary route. The drug-loaded carriers were characterized for their particle size, polydispersity index, zeta potential, and entrapment efficiency. The ex vivo rat skin permeation studies indicated that when compared to LPT dispersion and 5-FU solution, drug-loaded transfersomes exhibited better permeability and their transpapillary permeation was enhanced on using iontophoresis. Moreover, both LPT and 5-FU transfersomes were found to be stable for 3 months when stored at a temperature of 5 ± 3 °C. The results indicated that this treatment strategy could be an effective approach in contrast to some of the conventional treatments employed to date.

Transpapillary iontophoretic delivery of resveratrol loaded transfersomes for localized delivery to breast cancer

Localized drug delivery to the breast tissues is an area of interest as a potential route to ensure site-specific drug delivery. Transpapillary delivery via the mammary papilla has advantages as most breast tumors arise from the milk ducts. The present study explored the plausibility of transpapillary delivery of a phytochemical, resveratrol (RVT), for breast cancer treatment. RVT was encapsulated within the transfersomes (RVT-TRF) to enable a sustained release of the drug using the biomaterial soya phosphatidylcholine (SPC). Iontophoresis was applied to further accelerate the penetration of the RVT-TRF across the mammary papilla to the breast tissue. The RVT-TRF development was optimized by the Design of Experiments (DoE) approach. The in vitro transpapillary iontophoresis study on porcine mammary papilla showed an enhanced penetration of RVT-TRF when compared to passive diffusion. The transpapillary delivery was further confirmed from the in vitro fluorescent microscopy study using FITC conjugated RVT-TRF. The optimized RVT-TRF delivered via transpapillary route showed a higher C_max and AUC when compared to pure RVT given orally. A significant reduction in the tumor volume and the serum biomarker CA 15-3, when evaluated in a chemically induced breast cancer rat model, provided evidence of the effectiveness of the developed formulation when delivered locally via transpapillary route compared to the oral route. Thus the developed RVT-TRF administered via transpapillary iontophoresis technique is a promising strategy enabling a localized delivery for effective breast cancer therapy.

Therapeutische Besonderheiten bei Erkrankungen der Mamillenhaut

Die Mamillenregion ist durch besondere anatomische Verhältnisse charakterisiert und lässt sich aus dermatologischer Perspektive in Brusthaut, Haut des Brustwarzenhofes (Areola) und Haut der Brustwarze (Papilla mammae) unterteilen. Im klinischen Zusammenhang sind die Brustwarzen häufig während der Stillzeit durch mechanische Beanspruchung, Milieuänderung mit Mazeration durch den Milchfluss sowie durch mikrobielle Erreger alteriert. Zudem besteht hier die Gefahr der Entwicklung einer Mastitis puerperalis. Außerhalb der Schwangerschaft und Stillzeit finden sich gelegentlich an der Mamillenhaut Ekzemerkrankungen, häufig bei atopischer Disposition (atopisches Mamillenekzem) oder als irritatives Kontaktekzem („joggers nipple“). Seltener werden allergische Kontaktekzeme auf Konservierungsstoffe von Topika oder Metallen (Piercings) beobachtet. Auch im Rahmen einer Skabiesinfestation wird eine Beteiligung der Mamillen, insbesondere bei Frauen, regelmäßig beobachtet. Von großer klinischer Bedeutung sind seltene, präinvasive Läsionen eines Mammakarzinoms oder der Morbus Paget der Mamille vom extramammären Typ. Durch die besonderen anatomischen Gegebenheiten ist es naheliegend, dass bei der Anwendung von Topika sich auch spezifische Penetrationsbedingungen ableiten. Experimentelle Untersuchungen an Humanhaut ex vivo legen nahe, dass in Abhängigkeit von der Molmasse und der Löslichkeit des Arzneistoffs sowie des eingesetzten Vehikelsystems eine deutliche Zunahme der kutanen Bioverfügbarkeit, insbesondere an der Brustwarze selbst durch den transpapillären Diffusionsweg, auftreten kann. Dies sollte insbesondere bei der topischen Anwendung von Arzneistoffen mit bekanntem dosisabhängigem Nebenwirkungspotenzial (z. B. Glukokortikoiden) beachtet werden. Allerdings fehlt dafür bisher eine klinische Evidenz.

Exploring potential formulation strategies for chemoprevention of breast cancer: a localized delivery perspective

This review focuses on the various formulation approaches that have been explored to achieve localized delivery in breast cancer. The rationale behind the necessity of localized drug delivery has been extensively reviewed. The review also emphasizes the various possible routes for achieving localized drug delivery. Particularly, different types of nanoplatforms like lipid-based drug carriers, polymeric particles, hydrogels, drug conjugates and other formulation strategies like microneedles and drug-eluting implants, which have been used to increase tumor retention and subsequently halt tumor progression, have been deliberated here. In addition, the significant challenges that may be encountered in the delivery of anticancer drugs and the aspects that require careful evaluation for effective localized delivery of chemotherapeutic agents have been discussed.

Strategic consideration for effective chemotherapeutic transportation via transpapillary route in breast cancer

Breast cancer is the most commonly occurring cancer in women and the second most common cancer overall. The current treatment option for breast cancer includes drug treatment (Chemotherapy and hormone therapy) or surgery (mastectomy and lumpectomy). The major drawbacks of chemotherapy include rapid metabolism, limited ductal exposure, lower bioavailability, higher elimination rate, undesirable side effects, and high dose of drug. Localized application of drug to breast achieves higher drug levels at the tumor site and reduces systemic drug distribution. Permeation of drug by local application is mainly by transepidermal and transductal routes. The multiple duct openings of mammary papilla provide a higher permeable surface for transport of drug. Various formulation approaches like conjugated nanocarriers, microemulsion, nanoemulsion, liposomes, microneedles and iontophoresis are used to achieve a tailored and targeted drug delivery to underlying breast tissue. Localized transport of drug via transpapillary route has developed a novel and effective non-invasive drug delivery approach to achieve a systemic drug level at the tumor site in the management of breast cancer.

Nanoemulsions Enhance in vitro Transpapillary Diffusion of Model Fluorescent Dye Nile Red

While the feasibility of transpapillary drug delivery has previously been established, localized transport via the mammary ducts may be improved with tailored drug delivery formulations. The objective of this study was to investigate the impact of nanoemulsion encapsulation on transpapillary delivery in vitro. Nanoemulsion formulations composed of isopropyl myristate and Tween 80 encapsulating a fluorescent dye were applied topically on porcine nipples using a Franz diffusion cell. A combination of dye extraction and fluorescence image analysis was used to quantify the total amount of dye retained within the nipple and to characterize the penetration routes. After diffusion for 6 hours, the amount of dye deposited in the nipple was proportional to the formulation’s water concentration. The 90% water formulation deposited significantly more dye via both the stratum corneum and mammary ducts, while the 80% and 70% water formulations moderately increased ductal penetration, but minimally altered stratum corneum penetration as compared to the control solution. Similar trends were found after diffusion for 48 hours; however, the overall impact was diminished, likely due to the nanoemulsion’s topical instability. This study indicates that drug delivery vehicles, nanoemulsions specifically, enhance delivery of encapsulated molecules via the stratum corneum and mammary ducts in a formulation-dependent basis.