Sara L. Tolliday, PharmD, RPh

The human body’s largest organ—the skin—serves as a first line of defense, and has essential immunological and biochemical roles. Aquaporins (AQPs), a group of membrane channels responsible for transmission of water and other small uncharged solutes, are heavily involved in the skin’s physiology. They are vital for skin hydration and wound healing. AQP dysfunction has been linked to melanoma and other skin disorders.

 in May 2021 suggests AQPs as potential drug targets for skin cancer. Recent innovations in melanoma biology indicate expression of 8 of the 13 AQP isoforms in melanoma cells. This review discusses current knowledge of AQP envelopment in skin’s function and pathology. Many studies outlined focus on AQP1 and AQP3 as possible melanoma drug targets.

In a small study comprised of 78 melanoma patients, AQP1-expressing cutaneous melanoma cells were present in 52 subjects. Those at high risk had elevated AQP1 levels. Follow-up with these patients showed a reduced survival rate, correlating AQP1 over-expression with negative prognosis. These authors found the same inverse relationship with AQP1 expression and survival in patients with extracranial metastasis. This data suggests AQP1 is a likely prognostic indicator for human cutaneous melanoma.

Another study that focused on AQP1’s anti-angiogenic features showed melanoma-afflicted mice with 75% tumor volume reduction after 6 days when injected intratumorally with AQP1 siRNA. Subsequent injections revealed inhibition of tumor growth. The same authors treated a mouse’s melanoma with these injections for 10 days and results showed inhibition of lung nodule growth and twice the survival rate compared to control mice.

AQP-modulating agent discovery has proved challenging, but many powerful AQP3 permeating molecules have been identified. Auphen, a gold-based compound, showed AQP3 permeability inhibition, reducing spread by 50% in AQP3-expressing tumors.

Cuphen, a strong copper-based AQP3 inhibitor, tended to suppress cell growth with minimal toxicity when studied in mice with melanoma. These results indicate auphen and cuphen as possible treatments for melanoma and other solid tumors.

Present knowledge suggests AQPs as promising drug targets for melanoma and other skin ailments. Further research regarding the roles of AQPs in both the presence and absence of skin disease is crucial to understand how AQP modulators can be applied in clinical practice.

is a full-time pharmacist at Wentworth-Douglass Hospital, Outpatient Pharmacy, Dover, NH.

da Silva IV, Silva AG, Pimpão C, Soveral G. Skin aquaporins as druggable targets: Promoting health by addressing the disease [published online ahead of print, 2021 Jun 11]. 

. 2021;S0300-9084(21)00146-2. doi:10.1016/j.biochi.2021.05.019

Articles

AQP-modulating agent discovery has proved challenging, but many powerful AQP3 permeating molecules have been identified.

Druggable Targets for Melanoma: Skin Aquaporins

Skin cancer is diagnosed more each year than all cancers combined, making it the most common cancer in the United States. Ultraviolet (UV) radiation from the sun is responsible for 90% of diagnosed nonmelanoma skin cancer (NMSC). Skin cancer can be prevented by reducing sun exposure and has a 99% 5-year survival rate when detected early.

Pharmacists often provide counseling regarding photosensitivity, a common drug adverse effect and are well-versed in over-the-counter products that prevent and treat sunburn. Their position is ideal to educate the public on skin cancer prevention.

Journal of American Pharmacists Association

 outlines Skin Cancer Awareness Now! (SCAN!), a sun safety project led by community pharmacists and pharmacy students. This study proved community pharmacies are model settings for skin cancer prevention education in rural communities with insufficient access to health care services.

The study authors piloted SCAN! in the Appalachian region—a vast medically underserved area with high skin cancer mortality. This vulnerable population needs accessible melanoma prevention and screening.

SCAN! had 2 elements: training for pharmacists and pharmacy students, and a 5–10-minute face-to-face counseling session delivered by those who were trained. Trainers recruited potentially eligible participants or obtained consent from patients presenting to participating pharmacies for routine services.

Trainers started their counseling with the Environmental Protection Agency’s sun safety handout, underscoring the importance of protective clothing, sunscreen, hat, shade, and sunglasses. Trainers also discussed the American Academy of Dermatology’s ABCDE (asymmetry, border, color, diameter, evolving) skin cancer acronym, and challenges patients may face while seeking preventive care. Participants completed a short postintervention survey.

Survey results indicated strong acceptance of and willingness to follow counseling recommendations.

A study limitation was the small sample size (n=90). A larger scale study is warranted to emphasize the positive influence SCAN! can have in the community pharmacy setting.

Pharmacist intervention can positively impact skin cancer’s ever-growing morbidity and mortality by providing underserved populations with access to prevention and sun safety awareness.

 is a full-time pharmacist at Wentworth-Douglass Hospital, Outpatient Pharmacy, Dover, New Hampshire.

. The Skin Cancer Foundation. Accessed 6 Jul 2021. 

https://www.skincancer.org/skin-cancer-information/skin-cancer-facts/

Kelly KM, Dhumal T, Scott VG, et al. SCAN! A pharmacy-based, sun safety feasibility study

 (2003). 2021;61(1):e69-e79. doi: 10.1016/j.japh.2020.10.004.

A recent study proved community pharmacies are model settings for skin cancer prevention education in rural communities with insufficient access to health care services.

Pharmacist-Led Sun Safety Education Can Expand Skin Cancer Awareness

Telemedicine increases health care accessibility and convenience while preventing excessive gathering of patients in hospitals or other medical offices. The “store-and-forward” method involves the physician forwarding a patient’s clinical history and findings to a specialist, who reviews and responds with a report later. This system of health care communication was found to be useful to evaluate the incidence of nonmelanoma skin cancer (NMSC), NMSC precursors, and melanoma.

Pharmacists’ vast health care knowledge and community accessibility makes them ideal patient liaisons. A study published in the 

Journal of the American Pharmacists Association

 in September 2020 used a direct-to-consumer, store-and forward teledermatology with dermoscopy using the pharmacist as the patient’s point-of-contact.

The study investigated 218 patients and 225 lesions underwent teledermatology consultation between September 2018 and March 2020. Patients requested teleconsultations at their local pharmacies where pharmacists evaluated the lesions using specific exclusion criteria. The pharmacist obtained patients’ medical histories and pertinent information such as sun exposure pattern, perceived changes and symptoms, and lesion duration and location. They sent patient information and 2 or more photos taken with immersion dermoscopy to a team of dermatologists for review. Pharmacists contacted patients once they received dermatologists’ reports containing the diagnosis and recommendations.

Most lesions were benign (53.8%), while 16.4% were dubious, 23.1% were NMSC precursors, 5.8% were NMSC, and 0.9% were melanomas. Dermatologyrecommended in-person consultation for 53.8% of cases, at which time they subtracted the cost of telecommunication from the cost of the in-person consultation.

From the patient’s perspective, this health care model’s benefits exceed its drawbacks. Pharmacy point-of-contact is a more convenient way to identify potential melanoma as no appointment is required. The cost is also less expensive—approximately one third of the cost of a typical office visit. Accessible, affordable care translates to higher rates of melanoma diagnosis and better prognoses.

A disadvantage is that this model is inappropriate for some patients. Pharmacists may triage certain patients who have lesions they deem unsuitable for teledermatology, recommending in-person consultation. In these cases, dermatology credited the cost of telecommunication against the in-person consultation’s cost, so patients were not penalized.

A direct-to-consumer store-and-forward teledermatology with dermoscopy, with the pharmacist as the point-of-contact, is a practical method in diagnosing melanoma, NMSC, and NMSC precursors when supported by a strong team of dermatologists.

Mendonça FI, Lorente-Lavirgen A, Domínguez-Cruz J, et al. Direct-to-consumer, store-and-forward teledermatology with dermoscopy using the pharmacist as patient point-of-contact. 

 (2003). 2021 Jan-Feb;61(1):81-86. doi: 10.1016/j.japh.2020.09.012.

Pharmacists’ vast health care knowledge and community accessibility makes them ideal patient liaisons. 