FGFR3 and PIK3CA mutations in stucco keratosis and dermatosis papulosa nigra

Photodynamic therapy for facial dermatosis papulosa nigra: Efficacy and safety in a preliminary study

Dermatosis papulosa nigra (DPN) is a type of benign epidermal hyperplasia that affects the appearance of patients and poses a threat to their physical and mental health. Photodynamic therapy (PDT) has been shown to have the advantages of non-invasiveness, efficacy, and low recurrence in the treatment of skin disorders. However, no studies have been reported on the use of PDT for the treatment of DPN. Therefore, we used PDT for the first time to treat DPN and monitor its efficacy. Forty-five patients with DPN diagnosed at the outpatient clinic of Changzhou First People's Hospital were treated with 10 % 5-aminolevulinic acid (ALA) once a week for four consecutive weeks and followed for 3 months. After four treatment sessions, the cure rate among the 45 patients was 71.1 %, and the overall efficacy rate was 93.3 %. The most common adverse reactions were mild erythema, edema, and temporary pigmentation. PDT is expected to become a new and effective treatment for DPN.

Seborrheic keratosis

Seborrheic keratosis (SK) is the most common benign epidermal tumor in clinical dermatological practice. This review summarizes current knowledge about the clinical and histological appearance, epidemiology, pathogenesis, and treatment of SK. There are different subtypes of SK based on clinical presentation and histologic findings. Several factors, including age, genetic predisposition, and possibly also exposure to ultraviolet radiation, are thought to contribute to the development of SK. The lesions can occur on all areas of the body except for the palms and soles, but the most common sites are the face and upper trunk. The diagnosis is usually made clinically, and in some cases by dermatoscopy or histology. Many patients prefer to have the lesions removed for cosmetic reasons although there is no medical indication. Treatment options include surgical therapy, laser therapy, electrocautery, cryotherapy, and topical drug therapy, which is currently in development. Treatment should be individualized depending on the clinical picture and patient preference.

Advances in the Etiology, Detection, and Clinical Management of Seborrheic Keratoses

Seborrheic keratoses (SKs) are ubiquitous, generally benign skin tumors that exhibit high clinical variability. While age is a known risk factor, the precise roles of UV exposure and immune abnormalities are currently unclear. The underlying mechanisms of this benign disorder are paradoxically driven by oncogenic mutations and may have profound implications for our understanding of the malignant state. Advances in molecular pathogenesis suggest that inhibition of Akt and APP, as well as existing treatments for skin cancer, may have therapeutic potential in SK. Dermoscopic criteria have also become increasingly important to the accurate detection of SK, and other noninvasive diagnostic methods, such as reflectance confocal microscopy and optical coherence tomography, are rapidly developing. Given their ability to mimic malignant tumors, SK cases are often used to train artificial intelligence-based algorithms in the computerized detection of skin disease. These technologies are becoming increasingly accurate and have the potential to significantly augment clinical practice. Current treatment options for SK cause discomfort and can lead to adverse post-treatment effects, especially in skin of color. In light of the discontinuation of ESKATA in late 2019, promising alternatives, such as nitric-zinc and trichloroacetic acid topicals, should be further developed. There is also a need for larger, head-to-head trials of emerging laser therapies to ensure that future treatment standards address diverse patient needs.

Differential Diagnosis and Management on Seborrheic Keratosis in Elderly Patients

Seborrheic keratoses are exceedingly common in the elderly and usually are easy to diagnose and do not require treatment. However, given their great variety of clinical presentation, they may give rise to false-positive cases, meaning that they may at times mimic melanoma, squamous cell carcinoma and basal cell carcinoma. On the other hand, melanoma may mimic seborrheic keratosis, leading to incorrect patient management. With this review, we would like to summarize the current knowledge about epidemiology, clinical, dermoscopic and reflectance confocal microscopy imaging of this common entity, and we also summarize the currently available treatment options.

Facial Hyperpigmentation in Skin of Color: Special Considerations and Treatment

Differences in cutaneous diseases in people of color call for nuanced evaluation and management. One of the most common dermatological complaints from patients with skin of color is dyspigmentation, particularly hyperpigmentation. The challenge for clinicians is to establish correct diagnoses along with consistently successful treatments to meet the needs of the increasingly diverse population served. This review focuses on facial hyperpigmentation and outlines the most common skin disorders and treatment options.

Sustained Akt Activity Is Required to Maintain Cell Viability in Seborrheic Keratosis, a Benign Epithelial Tumor

Seborrheic keratoses (SKs) are common benign skin tumors that share many morphological features with their malignant counterpart, squamous cell carcinoma. SKs frequently have acquired oncogenic mutations in the receptor tyrosine kinase/phosphatidylinositol 3-kinase/Akt signaling cascade. We developed a reliable culture system to study SKs in vitro and screened these cells using a library of selective kinase inhibitors to evaluate effects on cell survival. These benign tumors are sensitive to inhibition by ATP-competitive Akt inhibitors, including A-443654 and GSK690693. RNA interference-mediated Akt suppression mimicked the effects of enzyme inhibition in cultured cells. Akt inhibition suppressed phosphorylation of downstream targets of Akt kinase that are critical for cell survival, including MDM2 and FOXO3a, and induced apoptosis. Cell death was also dependent on p53, mutations in which, although common in cutaneous squamous cell carcinoma, have not been identified in SKs. Intact explants of SKs were also sensitive to Akt inhibition. In addition to the obvious therapeutic implications of these findings, identifying the signaling characteristics that differentiate benign and malignant tumors may inform our understanding of the malignant state.

Cutaneous clues for diagnosing X-chromosomal disorders

In a multidisciplinary outpatient clinic for hereditary skin diseases and/or syndromes involving the skin, 7% (30 of 409) of patients were found to have an abnormality involving the X chromosome, a mutation in a gene located on the X chromosome or a clinical diagnosis of an X-linked monogenetic condition. The collaboration of a dermatologist and a clinical geneticist proves to be very valuable in recognizing and diagnosing these conditions. By combining their specific expertize in counselling an individual patient, X-linked diagnoses were recognized and could be confirmed by molecular and/or cytogenetic studies in 24 of 30 cases. Mosaicism plays an important role in many X-linked hereditary skin disorders. From our experience, we extracted clinical clues for specialists working in the field of genetics and/or dermatology for considering X-linked disorders involving the skin.

[R248C FGFR3 mutation. Effect on cell growth, apoptosis and attachment in HaCaT keratinocytes]

Activating FGFR3 mutations have been identified in a variety of benign skin lesions (seborrheic keratosis, epidermal nevus, solar lentigo). However, the functional consequences of these mutations in the human epidermis are unknown. We therefore analyzed functional effects of the common R248C mutation in HaCaT keratinocytes. The cells were stably transduced with the R248C FGFR3 mutation or FGFR3-IIIb wildtype sequence using a retroviral system. The R248C mutant keratinocytes revealed significantly enhanced cell growth compared with wildtype cells after reaching confluence. Likewise, apoptosis and attachment to fibronectin were significantly reduced in mutant cells. In contrast, there was no difference regarding migration and oncogene-induced senescence. Gene expression analysis revealed only a few differentially expressed genes between mutant and wildtype HaCaT keratinocytes. ERK1/2 appear to be involved in the FGFR3-dependent signalling of R248C mutant keratinocytes. Our results indicate that an increased cell number at confluence along with reduced apoptosis may contribute to the growth of benign acanthotic tumors in the human epidermis.

NF449 is a novel inhibitor of fibroblast growth factor receptor 3 (FGFR3) signaling active in chondrocytes and multiple myeloma cells

The FGFR3 receptor tyrosine kinase represents an attractive target for therapy due to its role in several human disorders, including skeletal dysplasias, multiple myeloma, and cervical and bladder carcinomas. By using molecular library screening, we identified a compound named NF449 with inhibitory activity toward FGFR3 signaling. In cultured chondrocytes and murine limb organ culture, NF449 rescued FGFR3-mediated extracellular matrix loss and growth inhibition, which represent two major cellular phenotypes of aberrant FGFR3 signaling in cartilage. Similarly, NF449 antagonized FGFR3 action in the multiple myeloma cell lines OPM2 and KMS11, as evidenced by NF449-mediated reversal of ERK MAPK activation and transcript accumulation of CCL3 and CCL4 chemokines, both of which are induced by FGFR3 activation. In cell-free kinase assays, NF449 inhibited the kinase activity of both wild type and a disease-associated FGFR3 mutant (K650E) in a fashion that appeared non-competitive with ATP. Our data identify NF449 as a novel antagonist of FGFR3 signaling, useful for FGFR3 inhibition alone or in combination with inhibitors that target the ATP binding site.