Activation and overexpression of the aryl hydrocarbon receptor contribute to cutaneous squamous cell carcinomas: an immunohistochemical study.

BACKGROUND: In vitro studies showed that the aryl hydrocarbon receptor (AHR) contributed to the development of cutaneous squamous cell carcinomas, but supporting clinical data are lacking. METHODS: Immunohistochemical analysis was used to detect the expression of AHR, CYP1A1, EGFR, and Ki-67 in 10 actinic keratosis (AK) cases, 10 Bowen disease (BD) cases, 20 cutaneous squamous cell carcinoma (cSCC) cases and 20 normal skin samples. H-scores were used to assess the immunoreactivity. RESULTS: Weak positive AHR immunoreactivity was found in all normal skin samples, while strong positive AHR immunoreactivity was found in atypical squamous proliferation (AK, BD and cSCC) cases. H-scores and the rate of strong immunostaining of the atypical squamous proliferation cases were higher than those of normal controls (p < 0.01). Nuclear expression of AHR was higher in atypical squamous proliferation cases than in normal controls (p < 0.01). H-scores and the nuclear expression rate of AHR were significantly higher in AK and BD cases than cSCC cases (p < 0.01). CYP1A1 expression was low and showed no differences among the four studied groups (p > 0.05). The H-score of AHR was positively correlated with EGFR expression (r = 0.54, p < 0.01) in atypical squamous proliferation cases but was not correlated with CYP1A1 (r = - 0.17, p = 0.295) and Ki-67 (r = - 0.48, p = 0.222) expression. CONCLUSION: AHR plays a vital role in cSCC pathogenesis. The overexpression and activation of AHR are involved in the early development of skin cancers. AHR expression correlates with EGFR expression and may influence cell proliferation. AHR is a valuable therapeutic target for skin cancers.

Efficacy and Safety of Targeted High-Intensity Medium-Band (304-312 nm) Ultraviolet B Light in Pediatric Vitiligo.

BACKGROUND/OBJECTIVES: Phototherapy is a commonly used treatment for vitiligo that has demonstrated safety and efficacy. High-intensity targeted ultraviolet B (UVB) light (304-312 nm) delivered using a phototherapy device is a useful therapeutic option because it can induce repigmentation in a short time without global exposure to radiation, but information regarding this device in children is limited. METHODS: We performed a retrospective analysis of 95 patches of vitiligo in 27 children treated using a targeted phototherapy device. Phototherapy was administered twice a week. RESULTS: After the first 10 treatment sessions, 82 (86.3%) patches demonstrated some repigmentation and 36.8% achieved 50% or more repigmentation. After a mean of 20.4 treatment sessions, 86 patches (90%) demonstrated some repigmentation and 53.7% achieved 50% or more repigmentation. Responses varied depending on the anatomic location of the lesions. Better responses were usually observed on the face and trunk, whereas the extremities typically showed little response. Repigmentation was better in patients with active vitiligo than in those with stable vitiligo, with responses better with a disease duration of 1 year or less than in those with a duration of more than 1 year. There was no statistically significant difference in repigmentation between those with segmental and generalized vitiligo. The only short-term local side effect was mild erythema that required a decrease in dosage in six patients. CONCLUSION: Targeted high-intensity medium-band UVB phototherapy alone can produce clinical improvement in pediatric vitiligo and is well tolerated.

In vivo reflectance confocal microscopy of Basal cell carcinoma: feasibility of preoperative mapping of cancer margins.

BACKGROUND: Reflectance confocal microscopy (RCM) images skin at cellular resolution and has shown utility for the diagnosis of nonmelanoma skin cancer in vivo. It has the potential to define lesion margins before surgical therapy. OBJECTIVES: To investigate the feasibility of RCM in defining the margins of basal cell carcinoma before surgery. METHODS: The margins of 10 lesions were evaluated using RCM. Biopsies of the margins were used to confirm the results. A protocol was constructed to define margins. RCM was used to delineate preoperative surgical margins in 13 patients. Intraoperative frozen biopsy was used to confirm the margins. RESULTS: In seven of 10 (70.0%) cases, the margins of the cancer were identified suing RCM. The tumor island was the critical feature in identifying the margins. In 12 of 13 (92.3%) cases, frozen biopsy corroborated that the surgical margins delineated by RCM were clear. CONCLUSION: RCM imaging of the margins is feasible and demonstrates the possibility of preoperative mapping of cancer margins.

In vivo reflectance confocal microscopy of extramammary Paget disease: diagnostic evaluation and surgical management.

BACKGROUND: Extramammary Paget disease (EMPD) is a diagnostic challenge. In vivo reflectance confocal microscopy (RCM) has been reported to be useful for in vivo skin tumor evaluation. It may also assist in the surgical management of EMPD lesions. OBJECTIVE: We sought to describe confocal features of EMPD and correlate them with histopathologic findings. The potential of RCM to map the lesions for subsequent surgical management was also investigated. METHODS: A total of 23 lesions from 14 recruited patients were evaluated by RCM and histopathologic examination. RCM was used to delineate preoperative surgical margins in two patients. RESULTS: Erythematous, hyperpigmented, and hypopigmented lesions were evaluated by RCM and results were confirmed by histopathologic examination. Paget cells were observed throughout the epidermis. Typical Paget cells on RCM were characterized by a mild bright nucleus and dark cytoplasm, frequently twice the size of keratinocytes or larger. At the dermoepidermal junction, tumor nests were seen as dark glandular structures. A high density of dendritic cells was observed in pigmented lesions and a low density in erythematous lesions. Dilated vessels and inflammatory cells were seen in pigmented and erythematous lesions. Paget cells within the epidermis and nest structures at the dermoepidermal junction were seen in most lesions. These two features were useful for delineating the margins. Histologic examination corroborated the surgical margins found by RCM. LIMITATIONS: The sensitivity and specificity of these diagnostic features have not been fully studied, and differential diagnostic features require exploration. CONCLUSION: Features correlating well to histopathology are observed on the RCM of EMPD lesions. RCM may be used as an auxiliary diagnostic tool for the diagnosis and management of EMPD.

The application of ZnO luminescent nanoparticles in labeling mice.

Photoluminescent ZnO@polymer core-shell nanoparticles were used in mouse imaging through intradermal injections and intravenous injections, and the results proved that such ZnO fluorescence probes are nontoxic to live mice and have great potential in in vivo applications.

In vivo reflectance confocal microscopy for the differential diagnosis between vitiligo and nevus depigmentosus.

BACKGROUND: Nevus depigmentosus (ND) is frequently confused with vitiligo. Differential diagnosis can be difficult. In vivo reflectance confocal microscopy (RCM) is a noninvasive technique for real-time en face imaging of the superficial layers of the skin down to the superficial dermis with cellular level resolution close to conventional histopathology. In this study, we tried to use this new technology to study the features of the distribution of pigment cells of these two hypopigmentation disorders and then concluded the differential features. METHODS: Sixty vitiligo patients and 62 ND patients were enrolled in the study. Three points in each patient (lesional, margin of the lesions and adjacent non- lesional points) were examined with RCM. The gray value of image was quantified using software, and we calculated the relative gray value. RESULTS: The RCM image feature was different between vitiligo and ND patients. The differential diagnosis was made based on the following four RCM features: complete absence of pigment cells; the distribution of pigment cells; the margins; and the relative gray value. CONCLUSION: RCM can be used as an auxiliary diagnostic tool for the differential diagnosis between vitiligo and ND.