A comprehensive review of the medical and cosmetic applications of exosomes in dermatology.

BACKGROUND: Exosomes are a subset of extracellular vesicles that are released by all cell types and are theorized to play a crucial role in intercellular communication. Ranging from 40 to 160 nm in diameter, exosomes contain a variety of genetic materials including DNA, RNA, mRNA, metabolites, proteins, and lipids depending on their cellular origin. AIM: Given that intercellular communication is abetted by the exchange of cellular components via exosomes, their applied use can have important implications for disease pathology and exosome-based therapeutics. We provide a comprehensive review of the current application of exosomes in medical (and skin) diseases and in cutaneous medical aesthetics. METHODS: A literature search was conducted on PubMed reviewing exosomes and their application in medical and aesthetic fields. RESULTS: While the therapeutic use of exosomes in the treatment of medical and cosmetic dermatological procedures is promising, it is also important to note that most studies implementing exosomes as therapeutic agents have been conducted in preclinical models, thus highlighting the need for additional studies and clinical trials. One more important note in the aesthetic world associated with exosomes is that in the United States, at the time of this writing, exosomes may only be topically applied and not injected into the skin, as is done in many countries worldwide. CONCLUSION: There is a need for additional studies and clinical trials to evaluate the safety and therapeutic effect and safety of exosomes in medical and aesthetic fields.

Multiple Flesh-Colored Nodules: A Patient with Multiple BAP 1-Inactivated Melanocytic Tumors.

A 22-year-old man without previously known skin disease presented with multiple asymptomatic, skin-brown to red-brown papules on the head and neck for 1 year (Figure 1). The diagnoses considered included benign intradermal or compound nevi, atypical nevi, and neurofibromas. Shave biopsies of three lesions revealed intradermal melanocytic lesions comprising large epithelioid melanocytes flanked by small banal melanocytes (Figure 2). All nevi had a low proliferation index, absent junctional component as demonstrated by a dual Ki-67/Mart-1 immunostain, and no dermal mitotic figures. Immunostaining demonstrated lesional melanocytes positive for p16, but the larger epithelioid melanocytes in these lesions lacked nuclear expression of ubiquitin carboxyl-terminal hydrolase protein (BAP-1; Figure 3). The diagnosis of a BAP-1-inactivated nevus was made, and the patient was referred for genetic counseling and screening for associated malignancies. Given that the lesions involved deep margins, the same were completely excised.

The use of Janus kinase inhibitors and narrowband ultraviolet B combination therapy in non-segmental vitiligo.

Vitiligo is a depigmentation disorder of the skin that occurs secondary to the destruction of melanocytes by an immune-mediated process. Vitiligo clinically presents with depigmented macules and patches, most commonly on the face, acral sites, and genitalia. It can be characterized as generalized or localized based on distribution. The localized form can be further divided into segmental (linear, band-like, or Blaschkoid) and non-segmental vitiligo. The classical treatment of vitiligo includes topical steroids, pulsed oral steroids in unstable vitiligo, phototherapy, a combination of steroid therapy and phototherapy, surgical grafting, as well as intentional depigmentation therapy in severe cases. However, recent advances in understanding the immune mechanisms implicated in the pathogenesis of vitiligo have led to the use of an FDA-approved topical Janus kinase (JAK) inhibitors for vitiligo. Despite this novel therapy advancement, we recommend the addition of narrowband ultraviolet B (NB-UVB) to JAK inhibitors in patients with extensive and progressive lesions, or those not fully responsive to JAK inhibitor monotherapy.

Characteristics and outcomes of patients with multiple myeloma aged 21-40 years versus 41-60 years: a multi-institutional case-control study.

We compared the outcomes of multiple myeloma (MM) patients aged 21-40 and 41-60 years in the novel agent era. This case-control study included 1089 patients between 2000 and 2015. Cases and controls were matched for sex, International Staging System (ISS) stage and institution. There were 173 patients in the younger group and 916 patients in the older group. Younger patients presented with a higher incidence of lytic lesions (82% vs. 72%; P = 0·04) and high-risk cytogenetic abnormalities (83% vs. 68%; P = 0·007), but lower rate of elevated lactate dehydrogenase (21% vs. 44%; P < 0·001). Five- and 10-year overall survival (OS) in younger versus older patients was 83% vs. 67% and 56% vs. 39%, respectively (P < 0·001). Similar results were seen when studying the subset of 780 patients who underwent autologous transplantation. Younger patients with ISS stage 1 had a better OS than older patients (P < 0·001). There was no survival difference between younger and older patients with ISS stage 2 or 3. Younger MM patients, aged 21-40 years, treated in the era of novel agents have a better OS than their counterparts aged 41-60 years, but the survival advantage observed in younger patients was lost in more advanced stages of MM.