Non Melanoma Skin Cancer Pathogenesis Overview

Hippo Signaling Pathway as a New Potential Target in Non-Melanoma Skin Cancers: A Narrative Review

Non-melanoma skin cancers (NMSCs), including basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), are the most frequently diagnosed cancers in humans, however, their exact pathogenesis is not fully understood. In recent years, it has been hypothesized that the recently discovered Hippo pathway could play a detrimental role in cutaneous carcinogenesis, but no direct connections have been made. The Hippo pathway and its effector, YAP, are responsible for tissue growth by accelerating cell proliferation, however, YAP upregulation and overexpression have also been reported in numerous types of tumors. There is also evidence that disrupted YAP/Hippo signaling is responsible for cancer growth, invasion, and metastasis. In this short review, we will explore whether the Hippo pathway is an important regulator of skin carcinogenesis and if it could be a promising target for future therapies.

The Impact of the Circadian Clock on Skin Physiology and Cancer Development

Skin cancers are growing in incidence worldwide and are primarily caused by exposures to ultraviolet (UV) wavelengths of sunlight. UV radiation induces the formation of photoproducts and other lesions in DNA that if not removed by DNA repair may lead to mutagenesis and carcinogenesis. Though the factors that cause skin carcinogenesis are reasonably well understood, studies over the past 10–15 years have linked the timing of UV exposure to DNA repair and skin carcinogenesis and implicate a role for the body’s circadian clock in UV response and disease risk. Here we review what is known about the skin circadian clock, how it affects various aspects of skin physiology, and the factors that affect circadian rhythms in the skin. Furthermore, the molecular understanding of the circadian clock has led to the development of small molecules that target clock proteins; thus, we discuss the potential use of such compounds for manipulating circadian clock-controlled processes in the skin to modulate responses to UV radiation and mitigate cancer risk.

Economic evaluation of interventions to reduce solar ultraviolet radiation (UVR) exposure among construction workers

Solar ultraviolet radiation is one of the most common occupational carcinogens in Canada and is responsible for approximately 5,556 non-melanoma skin cancers per year. A large part of these cases are preventable by reducing solar ultraviolet radiation exposure. In this study, investigators estimated the potential economic impacts of different solar ultraviolet radiation reduction interventions among construction workers, as they are one of the largest at-risk occupational groups. Investigators performed an economic evaluation from a societal perspective, by comparing incremental costs in relation to incremental benefits achieved by two interventions-use of personal protective equipment by all exposed individuals and use of shade structure wherever and whenever feasible. Interventions costs were estimated for 2020-2050, and benefits with a 10-year delay, i.e., for the period 2030-2060. Economic evaluation estimates were reported by intervention costs, total costs of non-melanoma skin cancers cases averted, incremental cost per avert case, return on investment, and the break-even point. Various sensitivity analyses were undertaken with key parameters. Our findings indicate that if the rising trend of incidence continues, cases will be double in 2060, whereas by using personal protective equipment or shade structure, with the best-case scenario of full ultraviolet radiation removal, would result in 6,034 and 2,945 cases averted over 30 years, respectively. This translates into a total of $38.0 and $20.5 million of averted costs (all monetary values represented in 2017 Canadian dollars). Under this scenario investigators expect that by 2060, for every dollar invested in personal protective equipment and shade structures, $0.49 and $0.35 will be returned, respectively. Findings also suggested that under a conservative scenario, prevention of non-melanoma skin cancer cases by personal protective equipment and shade structures resulted in $5,812 and $7,355 incremental costs, respectively, over the 30-year period. This study provides important insights for decision makers about the potential impacts of solar ultraviolet radiation reduction interventions in the construction sector and other sectors with substantial outdoor work. Our estimates also can raise awareness of the importance of solar ultraviolet radiation reduction interventions.

Paraoxonase-2: A potential biomarker for skin cancer aggressiveness

BACKGROUND

Cutaneous neoplasms include melanoma and non-melanoma skin cancers (NMSCs). Among NMSCs, basal cell carcinoma (BCC) represents the most common lesion. On the contrary, although accounting for less than 5% of all skin cancers, melanoma is responsible for most of cutaneous malignancy-related deaths. Paraoxonase-2 (PON2) is an intracellular enzyme exerting a protective role against production of reactive oxygen species within mitochondrial respiratory chain. Recently, a growing attention has been focused on exploring the role of PON2 in cancer. The aim of this study was to investigate the diagnostic and prognostic role of PON2 in skin neoplasms.

MATERIALS AND METHODS

36 cases of BCC, distinguished between nodular and infiltrative lesions, as well as 29 melanoma samples were analysed by immunohistochemistry to evaluate PON2 protein expression. Subsequent statistical analyses were carried out to explore the existence of correlations between intratumour enzyme levels and clinicopathological features.

RESULTS

Results obtained showed PON2 overexpression in BCCs compared with controls. In particular, distinguishing between less and more aggressive tumour forms, we found no significant differences in enzyme levels between nodular BCCs and controls. Conversely, PON2 expression was significantly higher in infiltrative BCCs compared with controls. Moreover, the enzyme was strongly upregulated in melanoma samples with respect to controls. Interestingly, PON2 levels were positively correlated with Breslow thickness, Clark level, regression, mitoses, lymph node metastases, primary tumour (pT) parameter and pathological stage.

CONCLUSIONS

Reported findings seem to suggest that PON2 expression levels could be positively related with tumour aggressiveness of both BCC and melanoma.

Adhesion Molecules in Non-melanoma Skin Cancers: A Comprehensive Review

Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most frequently diagnosed cancers, generating significant medical and financial problems. Cutaneous carcinogenesis is a very complex process characterized by genetic and molecular alterations, and mediated by various proteins and pathways. Cell adhesion molecules (CAMs) are transmembrane proteins responsible for cell-to-cell and cell-to-extracellular matrix adhesion, engaged in all steps of tumor progression. Based on their structures they are divided into five major groups: cadherins, integrins, selectins, immunoglobulins and CD44 family. Cadherins, integrins and CD44 are the most studied in the context of non-melanoma skin cancers. The differences in expression of adhesion molecules may be related to the invasiveness of these tumors, through the loss of tissue integrity, neovascularization and alterations in intercellular signaling processes. In this article, each group of CAMs is briefly described and the present knowledge on their role in the development of non-melanoma skin cancers is summarized.

Metformin is associated with decreased risk of basal cell carcinoma: A whole-population case-control study from Iceland

BACKGROUND

Metformin has anticarcinogenic properties and is also known to inhibit the sonic hedgehog pathway, but population-based studies analyzing the potential protective effect for basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are needed.

OBJECTIVES

To delineate the association between metformin use and invasive SCC, SCC in situ (SCCis), and BCC.

METHODS

A population-based case-control study design was employed using all 6880 patients diagnosed in Iceland between 2003-2017 with first-time BCC, SCCis, or invasive SCC, and 69,620 population controls. Multivariate odds ratios (ORs) were calculated using conditional logistic regression.

RESULTS

Metformin was associated with a lower risk of developing BCC (OR, 0.71; 95% confidence interval [CI], 0.61-0.83), even at low doses. No increased risk of developing SCC was observed. SCCis risk was mildly elevated in the 501-1500 daily dose unit category (OR, 1.40; 95% CI, 1.00-1.96).

LIMITATIONS

This study was retrospective in nature with the inability to adjust for ultraviolet exposure, Fitzpatrick skin type, and comorbidities.

CONCLUSION

Metformin is associated with decreased risk of BCC development, even at low doses. Metformin might have potential as a chemoprotective agent for patients at high risk of BCC, although this will need confirmation in future studies.

Medicinal Plants Towards Modeling Skin Cancer

Skin cancer remains a major cause of mortality worldwide. It can be divided into melanoma and non-melanoma cancer, which comprise mainly squamous cell carcinoma and basal cell carcinoma. Although conventional therapies have ameliorated the management of skin cancer, the search for chemopreventive compounds is still the most effective and safer strategy to treat cancer. Nowadays, chemoprevention is recognized as a novel approach to prevent or inhibit carcinogenesis steps with the use of natural products. Crude extracts of plants and isolated phytocompounds are considered chemopreventive agents since they harbor anti-inflammatory, antioxidant and anti-oncogenic properties against many types of diseases and cancers. In this review, we will discuss the therapeutic effect and preventive potential of selected medicinal plants used as crude extracts or as phytocompounds against melanoma and non-melanoma cutaneous cancers.

Surgically Treated Advanced Cutaneous Squamous Cell Carcinoma of the Head and Neck: Outcome Predictors and the Role of Adjuvant Radiation Therapy

OBJECTIVES

Advanced cutaneous squamous cell carcinoma of the head and neck (CSCCHN) is associated with poor outcome despite multimodality therapy. Comprehensive risk stratification may pinpoint the most suitable adjuvant treatment. This study aimed to evaluate the outcomes of surgically treated locoregional CSCCHN and to identify prognostic indicators of treatment outcomes.

METHODS

We retrospectively analyzed disease variables, pathologic characteristics, and management in association with treatment outcomes of all consecutive advanced CSCCHN patients who underwent surgical resection at Tel Aviv Sourasky Medical Center.

RESULTS

From 2008 to 2018, 74 patients met the inclusion criteria. Only perineural invasion (PNI) was significantly associated with worse overall survival (OS) (P = .001). Location within the facial "mask areas" was significantly associated with pathologically negative cervical disease (P = .001). Forty-seven patients underwent adjuvant radiation therapy (RT) which significantly improved OS and disease-free survival versus surgery alone (P = .025 and P = 0.035, respectively).

CONCLUSION

PNI was associated with worse OS in surgically treated advanced CSCCHN. Adjuvant RT conferred better outcomes despite high risk features.

The Impact of Notch Signaling for Carcinogenesis and Progression of Nonmelanoma Skin Cancer: Lessons Learned from Cancer Stem Cells, Tumor Angiogenesis, and Beyond

Since many decades, nonmelanoma skin cancer (NMSCs) is the most common malignancy worldwide. Basal cell carcinomas (BCC) and squamous cell carcinomas (SCC) are the major types of NMSCs, representing approximately 70% and 25% of these neoplasias, respectively. Because of their continuously rising incidence rates, NMSCs represent a constantly increasing global challenge for healthcare, although they are in most cases nonlethal and curable (e.g., by surgery). While at present, carcinogenesis of NMSC is still not fully understood, the relevance of genetic and molecular alterations in several pathways, including evolutionary highly conserved Notch signaling, has now been shown convincingly. The Notch pathway, which was first developed during evolution in metazoans and that was first discovered in fruit flies (Drosophila melanogaster), governs cell fate decisions and many other fundamental processes that are of high relevance not only for embryonic development, but also for initiation, promotion, and progression of cancer. Choosing NMSC as a model, we give in this review a brief overview on the interaction of Notch signaling with important oncogenic and tumor suppressor pathways and on its role for several hallmarks of carcinogenesis and cancer progression, including the regulation of cancer stem cells, tumor angiogenesis, and senescence.

Role of occupational and recreational sun exposure as a risk factor for keratinocytic non-melanoma skin cancers: an Italian multicenter case-control study

BACKGROUND

Sun exposure is the main external risk factor for keratinocytic non-melanoma skin cancer (NMSC). Outdoor workers are at increased risk, but the relationship of NMSC with occupational solar exposure is often confounded by concurrent recreational sun exposure. We compared the percentage of outdoor workers in NMSC patients versus controls without history of NMSC and assessed occupational and recreational sun exposure in both groups, evaluating also other risk factors and use of protective measures.

METHODS

Adult NMSC patients and controls without history of NMSC or actinic keratoses, matched for sex and age range, were recruited in the Departments of Dermatology of seven Italian University Hospitals, with a 1:2 patient/control ratio whenever possible. Data were collected using specifically designed questionnaires.

RESULTS

Eight hundred thirty-four patients and 1563 controls were enrolled. History of outdoor work was significantly (P=0.033) more frequent in patients. Patients were more sun exposed from outdoor leisure activities (P=0.012) and sunbathed for longer periods (P=0.13) and between 12 pm and 3.30 pm (P=0.011). Cumulative sun exposure during hobbies was similar between patients and controls in outdoor workers, higher (P<0.05) in patients among indoor workers. Patients and controls with history of outdoor work were more sun exposed at work than during leisure activities (P<0.001). Use of sunscreens by outdoor workers was very low, particularly at work (19.9%). Patients used sunscreens more than controls (P=0.002).

CONCLUSIONS

Occupational and recreational sun exposure are relevant risk factors for outdoor and indoor workers respectively. Sunscreens are alarmingly underused, particularly at work, and are used mainly by patients.

Cancer-Associated Fibroblasts Differentiated by Exosomes Isolated from Cancer Cells Promote Cancer Cell Invasion

Cancer-associated fibroblasts (CAFs) in the cancer microenvironment play an essential role in metastasis. Differentiation of endothelial cells into CAFs is induced by cancer cell-derived exosomes secreted from cancer cells that transfer molecular signals to surrounding cells. Differentiated CAFs facilitate migration of cancer cells to different regions through promoting extracellular matrix (ECM) modifications. However, in vitro models in which endothelial cells exposed to cancer cell-derived exosomes secreted from various cancer cell types differentiate into CAFs or a microenvironmentally controlled model for investigating cancer cell invasion by CAFs have not yet been studied. In this study, we propose a three-dimensional in vitro cancer cell invasion model for real-time monitoring of the process of forming a cancer invasion site through CAFs induced by exosomes isolated from three types of cancer cell lines. The invasiveness of cancer cells with CAFs induced by cancer cell-derived exosomes (eCAFs) was significantly higher than that of CAFs induced by cancer cells (cCAFs) through physiological and genetic manner. In addition, different genetic tendencies of the invasion process were observed in the process of invading cancer cells according to CAFs. Our 3D microfluidic platform helps to identify specific interactions among multiple factors within the cancer microenvironment and provides a model for cancer drug development.

Metastatic basal cell carcinoma with atypical pattern of spread

Basal cell carcinoma is the most common malignancy in the United States. However, metastasis of basal cell carcinoma is exceedingly rare, with incidence estimates of 0.0028-0.055%. When it does metastasize, basal cell carcinoma most commonly spreads to regional lymph nodes and lungs, although other sites of disease can occur. This case report presents multi-modality imaging of a 54-year-old male who developed multifocal metastatic basal cell carcinoma approximately three years after initial presentation with an ulcerated groin lesion. Ultimately, metastases included many common and uncommon sites, including lymph nodes, lung, duodenum, spleen, and adrenal glands. This case provides an interesting example of an uncommon pattern of spread and associated symptoms of treatment-resistant metastatic basal cell carcinoma.

Basal Cell Carcinoma: From Pathophysiology to Novel Therapeutic Approaches

Basal cell carcinoma (BCC) is the most common human cancer worldwide, and is a subtype of nonmelanoma skin cancer, characterized by a constantly increasing incidence due to an aging population and widespread sun exposure. Although the mortality from BCC is negligible, this tumor can be associated with significant morbidity and cost. This review presents a literature overview of BCC from pathophysiology to novel therapeutic approaches. Several histopathological BCC subtypes with different prognostic values have been described. Dermoscopy and, more recently, reflectance confocal microscopy have largely improved BCC diagnosis. Although surgery is the first-line treatment for localized BCC, other nonsurgical local treatment options are available. BCC pathogenesis depends on the interaction between environmental and genetic characteristics of the patient. Specifically, an aberrant activation of Hedgehog signaling pathway is implicated in its pathogenesis. Notably, Hedgehog signaling inhibitors, such as vismodegib and sonidegib, are successfully used as targeted treatment for advanced or metastatic BCC. Furthermore, the implementation of prevention measures has demonstrated to be useful in the patient management.

Diagnostic Value of Real-Time Elastography in Diagnosing Lymph Node Metastasis of Skin Cancer

Objective

The purpose of this study was to examine the diagnostic performance of real-time tissue elastography in detecting lymph node involvement in skin cancers.

Methodology

We retrospectively analyzed B-mode sonography and real-time elastography (RTE) images of 70 lymph nodes from 34 patients diagnosed with squamous cell carcinoma (SCC) or malignant melanoma (MM). In the B-mode examination, the appearance or loss of the hilar architecture in the lymph node, contour lobulation, and the presence of focal cortical thickening were evaluated. Elastography scores were classified according to the ratio of soft and hard areas across the lymph node on a 4-point scale system. Largely soft lymph nodes were scored as “1” and largely hard lymph nodes were scored as “4”.

Results

When patients with SCC and MM were evaluated together, the sensitivity of elastography was 94%, specificity was 70%, and the accuracy rate was 86% in detecting lymph node involvement. When both tumor groups were evaluated separately, for SCC, the sensitivity of elastography was 90%, specificity was 61%, and the accuracy rate was 80% in detecting lymph node involvement. When the receiver operating characteristic (ROC) curve was taken, the area under the curve (AUC) was 0.78 for SCC. Elastography showed full compliance with pathology in lymph node metastases of MM and the AUC was 1.00.

Conclusions

Based on our findings, RTE provides important contributions to B-mode ultrasonography (USG) in evaluating lymph node metastases of skin cancers.

Environmental changes and their impact on human behaviour - Case study of the incidence of skin cancer

Climatological research over the past two decades makes it clear that the Earth's climate will change. Climate change has many, mostly adverse, effects on the human health. Environmental anthropogenic changes represent significant health risks including factors that may increase probability and seriousness of skin cancer diseases. There are many scientific studies on skin cancer but only a few of them are focused on environment changes and their influence on the behaviour of humans, which may lead to skin cancer. The goal of the research was to analyse environment changes in the city of Brno (Czech Republic) and their influence on the behaviour of people and some skin diseases. A research hypothesis was set up that total increase in the incidence of skin diseases would be monitored. 1757 patients aged 25-65 years participated in the research. The analysis was performed based on measured (mean annual temperatures, average monthly temperatures, ultraviolet index values, and numbers of sunny days and sunny hours) data in 2011-2019. In order to monitor the trend, temperature data from 1961 to 2019 were evaluated too. The analysed data indicate that the trend of average monthly and annual temperatures observed was increasing in recent years. Moreover, based on data obtained from the analysed doctor's office it was found out that the incidence of skin diseases increased in the studied period. The main reasons to increase include excessive exposure to sun, extended average age of the population, ozone layer depletion, climatic and weather changes, increased migration and behaviour of people.

Stimuli-responsive and cellular targeted nanoplatforms for multimodal therapy of skin cancer

Interdisciplinary applications of nanopharmaceutical sciences have tremendous potential for enhancing pharmacokinetics, efficacy and safety of cancer therapy. The limitations of conventional therapeutic platforms used for skin cancer therapy have been largely overcome by the use of nanoplatforms. This review discusses various nanotechnological approaches experimented for the treatment of skin cancer. The review describes various polymeric, lipidic and inorganic nanoplatforms for efficient therapy of skin cancer. The stimuli-responsive nanoplatforms such as pH-responsive as well as temperature-responsive platforms have also been reviewed. Different strategies for potentiating the nanoparticles application for cancer therapy such as surface engineering, conjugation with drugs, stimulus-responsive and multimodal effect have also been discussed and compared with the available conventional treatments. Although, nanopharmaceuticals face challenges such as toxicity, cost and scale-up, efforts put-in to improve these drawbacks with continuous research would deliver exciting and promising results in coming days.

Developing [60]Fullerene Nanomaterials for Better Photodynamic Treatment of Non-Melanoma Skin Cancers

Skin cancer is the most common cancer in the U.S.A. and Europe. Its subtype, squamous skin carcinoma (SCC), if allowed to grow, has the potential to metastasize and can become deadly. Currently, carbon nanomaterials are being developed to treat cancer due to their attractive physicochemical and biological properties such as an enhanced permeability effect and their ability to produce reactive oxygen species. Here, we describe the synthesis of two water-soluble aminofullerenes (MonoaminoC₆₀ and HexakisaminoC₆₀), which were evaluated as novel [60]fullerene based photosentizers exhibiting anticancer properties. Moreover, the previously described neutral glycofullerene GF1 and its peracetylated lipophilic precursor MMS48 were compared with the aminofullerenes for their ability to generate reactive oxygen species and oxidize lipids. Remarkably, the generation of singlet oxygen and a superoxide radical by HexakisaminoC₆₀ was found to be markedly elevated in the presence of bovine serum albumin and NADH, respectively. Mechanistic studies of lipid peroxidation using cholesterol as a unique reporter molecule revealed that although all four fullerene nanomaterials primarily generated singlet oxygen, superoxide anion was also formed, which suggest a mixed mechanism of action (in which Type I and Type II photochemistry is involved). The [60]fullerene derivative HexakisaminoC₆₀ was also studied for its phototoxicity in squamous skin cancer cell line (A431) using the MTT test and propidium iodide staining.

Current and Future Trends in Molecular Biomarkers for Diagnostic, Prognostic, and Predictive Purposes in Non-Melanoma Skin Cancer

Skin cancer represents the most common type of cancer among Caucasians and presents in two main forms: melanoma and non-melanoma skin cancer (NMSC). NMSC is an umbrella term, under which basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and Merkel cell carcinoma (MCC) are found along with the pre-neoplastic lesions, Bowen disease (BD) and actinic keratosis (AK). Due to the mild nature of the majority of NMSC cases, research regarding their biology has attracted much less attention. Nonetheless, NMSC can bear unfavorable characteristics for the patient, such as invasiveness, local recurrence and distant metastases. In addition, late diagnosis is relatively common for a number of cases of NMSC due to the inability to recognize such cases. Recognizing the need for clinically and economically efficient modes of diagnosis, staging, and prognosis, the present review discusses the main etiological and pathological features of NMSC as well as the new and promising molecular biomarkers available including telomere length (TL), telomerase activity (TA), CpG island methylation (CIM), histone methylation and acetylation, microRNAs (miRNAs), and micronuclei frequency (MNf). The evaluation of all these aspects is important for the correct management of NMSC; therefore, the current review aims to assist future studies interested in exploring the diagnostic and prognostic potential of molecular biomarkers for these entities.

Hydrogel-Based Technologies for the Diagnosis of Skin Pathology

Hydrogels, swellable hydrophilic polymer networks fabricated through chemical cross-linking or physical entanglement are increasingly utilized in various biomedical applications over the past few decades. Hydrogel-based microparticles, dressings and microneedle patches have been explored to achieve safe, sustained and on-demand therapeutic purposes toward numerous skin pathologies, through incorporation of stimuli-responsive moieties and therapeutic agents. More recently, these platforms are expanded to fulfill the diagnostic and monitoring role. Herein, the development of hydrogel technology to achieve diagnosis and monitoring of pathological skin conditions are highlighted, with proteins, nucleic acids, metabolites, and reactive species employed as target biomarkers, among others. The scope of this review includes the characteristics of hydrogel materials, its fabrication procedures, examples of diagnostic studies, as well as discussion pertaining clinical translation of hydrogel systems.

Association between hydrochlorothiazide and the risk of in situ and invasive squamous cell skin carcinoma and basal cell carcinoma: A population-based case-control study

BACKGROUND

Population-based studies analyzing hydrochlorothiazide's (HCTZ's) effect on keratinocyte carcinoma, and particularly invasive squamous cell carcinoma (SCC), are lacking.

OBJECTIVES

To characterize the association between HCTZ use and invasive SCC, SCC in situ (SCCis), and basal cell carcinoma (BCC).

METHODS

This population-based case-control study included all 6880 patients diagnosed with first-time BCC, SCCis, and invasive SCC between 2003 and 2017 in Iceland and 69,620 population controls. Conditional logistic regression analyses were used to calculate multivariate odds ratios (ORs) for keratinocyte carcinoma associated with HCTZ use.

RESULTS

A cumulative HCTZ dose above 37,500 mg was associated with increased risk of invasive SCC (OR, 1.69; 95% confidence interval [CI], 1.04-2.74). Users of HCTZ also had an increased risk of SCCis (OR, 1.24; 95% CI, 1.01-1.52) and BCC (OR, 1.14; 95% CI, 1.02-1.29).

LIMITATIONS

Limitations include this study's retrospective nature with the resulting inability to adjust for ultraviolet exposure, Fitzpatrick skin type, and comorbidities.

CONCLUSIONS

High cumulative exposure to HCTZ is associated with the development of keratinocyte carcinoma and, most importantly, invasive SCC. Sun protective behaviors alone may not eliminate the carcinogenic potential of HCTZ.

Plasma Treatment Limits Cutaneous Squamous Cell Carcinoma Development In Vitro and In Vivo

Cutaneous squamous cell carcinoma (SCC) is the most prevalent cancer worldwide, increasing the cost of healthcare services and with a high rate of morbidity. Its etiology is linked to chronic ultraviolet (UV) exposure that leads to malignant transformation of keratinocytes. Invasive growth and metastasis are severe consequences of this process. Therapy-resistant and highly aggressive SCC is frequently fatal, exemplifying the need for novel treatment strategies. Cold physical plasma is a partially ionized gas, expelling therapeutic doses of reactive oxygen and nitrogen species that were investigated for their anticancer capacity against SCC in vitro and SCC-like lesions in vivo. Using the kINPen argon plasma jet, a selective growth-reducing action of plasma treatment was identified in two SCC cell lines in 2D and 3D cultures. In vivo, plasma treatment limited the progression of UVB-induced SSC-like skin lesions and dermal degeneration without compromising lesional or non-lesional skin. In lesional tissue, this was associated with a decrease in cell proliferation and the antioxidant transcription factor Nrf2 following plasma treatment, while catalase expression was increased. Analysis of skin adjacent to the lesions and determination of global antioxidant parameters confirmed the local but not systemic action of the plasma anticancer therapy in vivo.

Tumor-Associated Neutrophils Dampen Adaptive Immunity and Promote Cutaneous Squamous Cell Carcinoma Development

Cutaneous squamous cell carcinoma (cSCC) development has been linked to immune dysfunctions but the mechanisms are still unclear. Here, we report a progressive infiltration of tumor-associated neutrophils (TANs) in precancerous and established cSCC lesions from chemically induced skin carcinogenesis. Comparative in-depth gene expression analyses identified a predominant protumor gene expression signature of TANs in lesions compared to their respective surrounding skin. In addition, in vivo depletion of neutrophils delayed tumor growth and significantly increased the frequency of proliferating IFN-γ (interferon-γ)-producing CD8+ T cells. Mechanisms that limited antitumor responses involved high arginase activity, production of reactive oxygen species (ROS) and nitrite (NO), and the expression of programmed death-ligand 1 (PD-L1) on TAN, concomitantly with an induction of PD-1 on CD8⁺ T cells, which correlated with tumor size. Our data highlight the relevance of targeting neutrophils and PD-L1-PD-1 (programmed death-1) interaction in the treatment of cSCC.

Detection of human papillomaviruses in paired healthy skin and actinic keratosis by next generation sequencing

Actinic keratosis (AK) arises on photo-damaged skin and is considered to be the precursor lesion of cutaneous squamous cell carcinoma (cSCC). Many findings support the involvement of β human papillomaviruses (HPVs) in cSCC, while very little is known on γ HPV types. The objective of this study was to characterize the spectrum of PV types in healthy skin (HS) and AK samples of the same immunocompetent individuals using next generation sequencing (NGS). Viral DNA of 244 AK and 242 HS specimens were amplified by PCR using two different sets of primers (FAP59/64 and FAPM1). Purified amplicons were pooled and sequenced using NGS. The study resulted in the identification of a large number of known β and γ PV types. In addition, 27 putative novel β and 16 γ and 4 unclassified PVs were isolated. HPV types of species γ-1 (e.g. HPV4) appeared to be strongly enriched in AK versus HS. The NGS analysis revealed that a large spectrum of known and novel PVs is present in HS and AK. The evidence that species γ-1 HPV types appears to be enriched in AK in comparison to HS warrants further studies to evaluate their role in development of skin (pre)cancerous lesions.

Silibinin and non-melanoma skin cancers

Skin is the largest human organ that shields the inner body from contact with xenobiotic and genotoxic agents, and in this process, the skin's cellular genome faces continuous stress due to direct exposure to these noxious factors. Accumulation of genetic stress results in genomic alterations leading to undesirable gene or protein alteration/expression in skin cells, which eventually causes the formation of non-melanoma skin cancers (NMSCs). Ultraviolet B (UVB) radiation from sun is the most prominent factor contributing to ∼5 million skin cancer cases (which are mostly NMSCs) in the United States (US) and western countries. UVB exposure causes aberrations in a range of biochemical and molecular pathways such as: thymine dimer formation, DNA damage, oxidative stress, inflammatory responses, altered cellular signaling, which ultimately contribute to the development of NMSCs. The focus of this review is to summarize the protective and preventive potential of silymarin and/or silibinin against UVB-induced NMSC in pre-clinical skin cancer studies. Over two decades of research has shown the strong potential of silibinin, a biologically active flavonolignan (crude form Silymarin) derived from milk thistle plant, against a wide range of cancers, including NMSCs. Silibinin protects against UVB-induced thymine dimer formation and in turn promotes DNA repair and/or initiates apoptosis in damaged cells via an increase in p53 levels. Additionally, silibinin has shown strong efficacy against NMSCs via its potential to target aberrant signaling pathways, and induction of anti-inflammatory responses. Overall, completed comprehensive studies suggest the potential use of silibinin to prevent and/or manage NMSCs in humans.

Evaluation of the Effectiveness of Additional Risk Minimization Measures for Voriconazole in the EU: Findings and Lessons Learned from a Healthcare Professional Survey

BACKGROUND

Voriconazole is an extended-spectrum antifungal agent approved for the treatment and prophylaxis of invasive aspergillosis and other serious fungal infections. In 2014, additional risk minimization measures (aRMM) consisting of a Healthcare Professional (HCP) Question and Answer (Q&A) Brochure, HCP Checklist, and Patient Alert Card were implemented on a rolling basis across the European Union (EU) to mitigate three key risks with voriconazole: phototoxicity, squamous cell carcinoma (SCC) of the skin, and hepatotoxicity. The risks of phototoxicity and hepatotoxicity have been documented in the Summary of Product Characteristics (SmPC) since voriconazole was first approved in the EU in 2002. However, the risk of SCC of the skin was a more recent addition to the SmPC (added in 2010).

OBJECTIVES

We evaluated the effectiveness of the aRMM, as per EU Good Pharmacovigilance Practices Module XVI, via a survey of HCPs.

METHODS

An online survey was conducted among specialty care HCPs in 10 EU countries who had received by mail aRMM tools 12 months previously. Survey questions evaluated HCPs' receipt and utilization of aRMM tools, and knowledge of the three risks.

RESULTS

Of 27,396 HCPs invited to participate, 332 eligible respondents completed the survey (response rate: 447/26,735; 1.7%). In total, 19.6% of respondents recalled receiving the HCP Q&A Brochure, 22.6% the HCP Checklist, and 25.9% the Patient Alert Card. HCPs had a high level of knowledge of phototoxicity and hepatotoxicity; however, knowledge of SCC was lower. Knowledge of the three risks and self-reported risk minimization behavior was slightly improved in those who had read the HCP Q&A Brochure compared with those who had not.

CONCLUSION

The effectiveness of the voriconazole aRMM cannot be meaningfully inferred from the results due to the low survey response rate. The assessment indirectly points to the SmPC or other resources being the main source of risk information for HCPs. Engaging HCPs before designing and implementing an aRMM program is crucial to ensure an effective and focused program. (EU PAS registration number: EUPAS12624).

Density of Langerhans Cells in Nonmelanoma Skin Cancers: A Systematic Review

Langerhans cells (LCs) are bone marrow-derived dendritic cells (DCs) that represent 2-3% of the entire cell population of the human skin, known to have an ability to present antigens to T lymphocytes. Moreover, there is evidence that LCs are probably capable of inducing the local cytotoxic type T-cell-mediated response against the tumour-associated antigens. In the past two decades, a dramatic increase has been noted in the incidence of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). The purpose of this study was to critically assess the results of available studies quantitatively assessing the LCs in nonmelanoma skin cancers and try to establish a conclusion of its possible impact on their future treatment. The PubMed, EMBASE, and the Web of Science databases were searched, which returned 948 citations. After a thorough analysis of full article texts, 30 studies have been chosen, including 11 of the BCC, 12 of the SCC specimens, and 7 analysing both tumour types. There was an overall trend towards slightly higher numbers of LCs in BCC than in SCC; however, these tendencies were discrepant between the studies. We presume that such differences could be caused by various staining techniques with a broad spectrum of specificity, including anti-S100, anti-CD1a, and ATPase activity staining used for LCs identification. We hypothesise that as there is a high inconsistency between the results of the studies, as far as the densities of LCs observed in the specimens are concerned, it seems that the mechanism of the influence of LCs on the antitumoural immune response is complicated. Finally, as at present, there is a paucity of available risk scores for the recurrence or progression of BCC or SCC, the creation of classification stratifying that risk including the density of LCs could bring additional information both for the physician and the patient.

AK-DL: A Shallow Neural Network Model for Diagnosing Actinic Keratosis with Better Performance Than Deep Neural Networks

Actinic keratosis (AK) is one of the most common precancerous skin lesions, which is easily confused with benign keratosis (BK). At present, the diagnosis of AK mainly depends on histopathological examination, and ignorance can easily occur in the early stage, thus missing the opportunity for treatment. In this study, we designed a shallow convolutional neural network (CNN) named actinic keratosis deep learning (AK-DL) and further developed an intelligent diagnostic system for AK based on the iOS platform. After data preprocessing, the AK-DL model was trained and tested with AK and BK images from dataset HAM10000. We further compared it with mainstream deep CNN models, such as AlexNet, GoogLeNet, and ResNet, as well as traditional medical image processing algorithms. Our results showed that the performance of AK-DL was better than the mainstream deep CNN models and traditional medical image processing algorithms based on the AK dataset. The recognition accuracy of AK-DL was 0.925, the area under the receiver operating characteristic curve (AUC) was 0.887, and the training time was only 123.0 s. An iOS app of intelligent diagnostic system was developed based on the AK-DL model for accurate and automatic diagnosis of AK. Our results indicate that it is better to employ a shallow CNN in the recognition of AK.

Prevalence, Incidence, and Risk of Cancer in Patients With Psoriasis and Psoriatic Arthritis: A Systematic Review and Meta-analysis

Importance

The association between psoriasis and risk of cancer remains debatable.

Objective

To evaluate the association and risk of cancer in patients with psoriasis or psoriatic arthritis, including risk of specific cancer subtypes.

Data Sources

Two databases (PubMed and Embase) were screened from inception to January 1, 2019, using the search string psoriasis or psoriatic and neoplasms or malignancy or cancer. The search was filtered to only include human participants and publications in English.

Study Selection

Observational cohort studies with a population of patients with psoriasis or psoriatic arthritis were included. Studies had to be original and report the incidence or prevalence of cancer within this population. Studies evaluating pediatric populations and cancer types not included in the protocol were excluded.

Data Extraction and Synthesis

This study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The search string, objectives, and study protocol methods were defined before the study was initiated. A total of 365 studies were included for full-text assessment. Owing to the heterogeneity of the included studies, a random-effects model was used.

Main Outcomes and Measures

Main outcome was cancer (overall and specific subtypes) and measures were prevalence, incidence, and risk estimate for cancer in patients with psoriasis or psoriatic arthritis.

Results

Of the 365 studies assessed, 112 were included in the analysis (N = 2 053 932 patients). The overall prevalence of cancer in patients with psoriasis was 4.78% (95% CI, 4.02%-5.59%), with an incidence rate of 11.75 per 1000 person-years (95% CI, 8.66-15.31) and a risk ratio (RR) of 1.21 (95% CI, 1.11-1.33). There was an increased risk of several cancers, including keratinocyte cancer (RR, 2.28; 95% CI, 1.73-3.01), lymphomas (RR, 1.56; 95% CI, 1.37-1.78), lung cancer (RR, 1.26; 95% CI, 1.13-1.40), and bladder cancer (RR, 1.12; 95% CI, 1.04-1.19). No increased risk of cancer for patients with psoriasis treated with biologic agents was found (RR, 0.97; 95% CI, 0.85-1.10). Psoriatic arthritis was not associated with increased risk of cancer overall (RR, 1.02; 95% CI, 0.97-1.08).

Conclusions and Relevance

Patients with psoriasis appear to have a slightly increased risk of cancer, particularly keratinocyte cancer and lymphomas. Data on treatment with biologic agents did not show an increased risk of cancer. Data on cancer in patients with psoriatic arthritis remain scarce, and further research is warranted in this area.

Validation Study of the AJCC Cancer Staging Manual, Eighth Edition, Staging System for Eyelid and Periocular Squamous Cell Carcinoma

Importance

To our knowledge, there are no validation studies to date of the prognostic value of the AJCC Cancer Staging Manual, eighth edition (AJCC 8), criteria for eyelid and periocular squamous cell carcinoma.

Objective

To determine the association of tumor (T) category in AJCC 8 with local recurrence, nodal metastasis, distant metastasis, and disease-specific survival (DSS) for eyelid and periocular squamous cell carcinoma.

Design, Setting, and Participants

In this retrospective, single-center cohort study, 109 consecutive patients with eyelid and periocular squamous cell carcinoma treated from January 1999 to April 2018 were included. Patients with secondary involvement of the periocular region were excluded.

Main Outcomes and Measures

Local recurrence, nodal metastasis, distance metastasis, and DSS.

Results

Of the 109 included patients, 81 (74.3%) were male, and the median (range) age was 66 (40-91) years. At presentation, 43 patients (39.4%) had recurrent tumor, 4 (3.7%) had nodal metastasis, and 1 (0.9%) had distant metastasis. The median (range) follow-up was 23 (1-161) months. During follow-up, 11 patients (10.1%) developed local recurrence, 7 (6.4%) developed nodal metastasis, 2 (1.8%) developed distant metastasis, and 9 (8.3%) died of disease. The 5-year DSS rate was 87.7% (95% CI, 79.5-96.9). Chronic immunosuppression (hazard ratio, 47.24; 95% CI, 7.33-304.30; P < .001) and presentation with recurrent squamous cell carcinoma (hazard ratio, 5.22; 95% CI, 1.12-24.31; P = .04) were associated with local recurrence during follow-up. Of the 11 patients with local recurrence during follow-up, 7 (64%) had perineural invasion. T category was associated with nodal metastasis; clinical stage of T2c or worse at presentation was associated with higher risk of nodal metastasis and death of disease but not with a higher risk of local recurrence. Distant metastasis was associated with nodal metastasis at presentation (hazard ratio, 32.50; 95% CI, 1.97-536.40; P = .02) and during follow-up. A total of 33 patients (30.3%) had different T categories depending on whether disease was staged according to the seventh or eighth edition of the AJCC Cancer Staging Manual. Compared with AJCC 7, AJCC 8 showed a better predictive value in terms of local recurrence (T3, 17% vs 14%; T4, 11% vs 16%) and DSS.

Conclusions and Relevance

These findings suggest that T category in AJCC 8 is associated with nodal metastasis and DSS. Immunosuppression and presentation with recurrent disease are associated with increased risk of future local recurrence. Patients with tumors of clinical stage T2c or worse at presentation are at increased risk of nodal metastasis and worse DSS and should undergo surveillance for nodal metastasis. Future studies, ideally prospective in design, could provide greater confidence in these findings.

Balance between Health Risks and Benefits for Outdoor Workers Exposed to Solar Radiation: An Overview on the Role of Near Infrared Radiation Alone and in Combination with Other Solar Spectral Bands

Near infrared or infrared A (IRA) accounts for over 40% of the solar spectrum (SS) and is able to reach subcutaneous tissue as well as the retina. Outdoor workers are occupationally exposed to solar radiation (SR), but the level of exposure may differ widely depending on the job performed, time spent outdoors, latitude, altitude, season, personal protection, etc. Until now, risk assessment and management for outdoor workers has focused on the prevention of both acute and long-term effects on the eye and the skin due to solar ultraviolet radiation (UVR) with little consideration of the other components of the SS (a possible exception is represented by visible radiation with reference to the eye). A growing body of evidence coming from in vitro studies indicates that IRA is involved in cellular reactive oxygen species (ROS) production and may interfere with the respiratory chain in the mitochondria. Moreover, it can modulate gene expression and some metabolic pathways. The biological action of IRA is only partly attributable to a thermal mechanism, should it be also involved in photochemical ones. The cellular and molecular pathways affected by IRA are partly similar and partly different with respect to those involved in the case of visible ultraviolet A (UVA) and ultraviolet B (UVB) radiation. Consequently, the net effect of the SS is very difficult to predict at different levels of the biological organization, making more difficult the final balance of health risk and benefits (for the skin, eye, immune system, blood pressure, etc.) in a given exposure situation. Moreover, few in vivo studies and no epidemiological data are presently available in this regard. Investigating this topic may contribute to better defining the individual exposome. More practically, it is expected to bring benefits to the risk assessment and management for outdoor workers exposed to SS, contributing to: (1) better definition of the individual profiles of susceptibility, (2) more focused preventive and protective measures, (3) better implementation of the health surveillance and (4) a more effective information and training.

Does the Autophagy Related Gene 7 (ATG7) Have a Role in Non-Melanoma Skin Cancer?

Purpose

To evaluate the role of autophagy related gene 7 (ATG7) in non-melanoma skin cancer.

Subjects and Methods

This retrospective and prospective case-control study was performed on 104 patients with non-melanoma skin cancer (NMSC) in addition to 20 apparently healthy subjects matched for age and sex as a control group. Multiple skin biopsies were taken for immunohistochemical evaluation of ATG7 expression.

Results

Both epithelial and stromal ATG7 were expressed in all participants while all patients showed nucleocytoplasmic localization and controls showed both cytoplasmic and nucleocytoplasmic expression. In addition, significantly higher H-scores of ATG7 in both epithelium and stroma were detected in patients compared to controls (P<0.001).

Conclusion

ATG7 nucleocytoplasmic topographic localization might be involved in the pathogenesis of NMSC, which can open the gate for new target therapy for this skin cancer.

Nanotechnology approaches in the current therapy of skin cancer

Skin cancer is a high burden disease with a high impact on global health. Conventional therapies have several drawbacks; thus, the development of effective therapies is required. In this context, nanotechnology approaches are an attractive strategy for cancer therapy because they enable the efficient delivery of drugs and other bioactive molecules to target tissues with low toxic effects. In this review, nanotechnological tools for skin cancer will be summarized and discussed. First, pathology and conventional therapies will be presented, followed by the challenges of skin cancer therapy. Then, the main features of developing efficient nanosystems will be discussed, and next, the most commonly used nanoparticles (NPs) described in the literature for skin cancer therapy will be presented. Subsequently, the use of NPs to deliver chemotherapeutics, immune and vaccine molecules and nucleic acids will be reviewed and discussed as will the combination of physical methods and NPs. Finally, multifunctional delivery systems to codeliver anticancer therapeutic agents containing or not surface functionalization will be summarized.

Optical coherence tomography in the assessment of cutaneous cancer margins of the face: An immediate ex vivo study

BACKGROUND

The assessment of cutaneous cancer margins intra-operatively or in the immediate postoperative phase can guide the operator into achieving clear margins. Achieving clear (tumour-free) margins following surgery is an essential factor that can reduce morbidity and disfigurement. The aim of present study was to determine the accuracy of optical coherence tomography in assessing cutaneous cancer margins of the face.

MATERIALS AND METHODS

The excised tissue specimens that were examined, in this study, were acquired from 70 patients with 70 facial cancer lesions, with no nodal disease. Forty lesions were basal cell carcinomas (150 margins; 27 tumour positive) and the remaining thirty were cutaneous squamous cell carcinomas (112 margins; 22 tumour positive). These 70 resected lesions were subjected to optical coherence tomography (OCT) in the immediate ex vivo phase to assess each specimen's four margins status (anterior, posterior, medial and lateral). Two reviewers, blinded to the diagnosis, carried out the assessment of the acquired OCT images and measured the mean thickness. Intra- and inter-reviewer agreement was also calculated.

RESULTS

On OCT, tumour-involved margins displayed sudden change in thickness associated with architectural changes. BCC-involved margins showed homogenous oval nests with dark rim and dark cysts or an empty space below dermo-epidermal junction depending on the sub-type. In the case of cutaneous SCC-involved margins, the DEJ had lost its integrity with/out the presence of small bright clusters in the papillary dermis and damage to the superficial epidermal layers. The mean thickness of the whole epidermal layer of the tumour-free margin was 128 μm, while for the BCC-involved margin 640 μm, and for the cutaneous SCC-involved margin 810 μm. The sensitivity of using OCT in examining BCC-involved margins was 88.9-92.6 % and the specificity was 96.8-98.4 %. For cutaneous SCC-involved margins, the sensitivity was 81.8-91.0 % and the specificity 85.6-91.1 %. There was "strong" inter-reviewer agreement on the BCC-involved margins, while the agreement was "moderate" for the cutaneous SCC-involved margins.

CONCLUSION

OCT provides good accuracy in identifying cutaneous cancer margins. This can potentially be used to guide and monitor resection in real-time. Tumour thickness could be measured due to the thin skin of the face, but may be more difficult to measure accurately in thick tumours and/or thick skin areas.

Association between Human Leukocyte Antigen Type and Keratinocyte Carcinoma Risk in Renal Transplant Recipients

Keratinocyte carcinoma (KC), defined as squamous cell carcinoma and basal cell carcinoma, is the most common malignancy among white, non-Hispanic renal transplant recipients. Although recent genome-wide association studies reported that class II HLA is associated with KC risk, epidemiologic data on HLA type and KC risk in renal transplant recipients is limited. Using an institutional cohort of white, non-Hispanic renal transplant recipients transplanted between 1993 and 2017, we examined the association between pretransplant molecular HLA types and KC risk. Posttransplant KCs were captured using the International Classification of Diseases codes and validated using pathology reports. Cox proportional hazards regression models were used to estimate hazard ratios of incident KC, squamous cell carcinoma, and basal cell carcinoma, adjusting for age, male sex, history of KC, Charlson comorbidity index, HLA mismatch, transplant type, year of transplant, and the type of immunosuppression. Among 617 subjects (mean age 53 years, 67% male), 10% developed posttransplant KC. Multivariable Cox regression analyses showed HLA-DRB1∗13 was associated with KC risk (hazard ratio, 1.84; 95% confidence interval, 1.00-3.38) and squamous cell carcinoma risk (hazard ratio, 2.24; 95% confidence interval, 1.12-4.49), whereas HLA-DRB1∗14 (hazard ratio, 2.81; 95% confidence interval, 1.14-6.91) was associated with basal cell carcinoma risk. Our findings suggest that a subset of renal transplant recipients with specific HLA polymorphisms may be at increased KC risk.

Long non-coding RNA HOTAIR functions as a competitive endogenous RNA to regulate PRAF2 expression by sponging miR-326 in cutaneous squamous cell carcinoma

Background

LncRNAs may exert a regulatory effect in tumorigenesis. Although the expression of lncRNA HOTAIR has been confirmed to be notably elevated in the tissues of CSCC, its biological mechanism in CSCC is still unknown.

Methods

HOTAIR expression level in CSCC cell lines was monitored via qRT-PCR. Then CCK-8 assay, Transwell assay and EdU assay were adopted to detect cell migration and proliferation. Meanwhile, through bioinformatics analysis and luciferase reporter gene detection, a new target of HOTAIR was identified. Additionally, Western blotting and RIP analysis were adopted to discuss the possible mechanism.

Results

HOTAIR expression in CSCC cell lines exhibited an obvious elevation. Cell function analysis revealed that HOTAIR overexpression remarkably facilitated CSCC cell migration, proliferation and EMT process, which were impeded by down-regulation of HOTAIR. Furthermore, HOTAIR competitively bound to miR-326, so as to positively modulate miR-326 expression.

Conclusions

These results present that HOTAIR, as a ceRNA, regulates PRAF2 expression by competitive binding to miR-326 during CSCC.

Combined analysis of keratinocyte cancers identifies novel genome-wide loci

The keratinocyte cancers (KC), basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most common cancers in fair-skinned people. KC treatment represents the second highest cancer healthcare expenditure in Australia. Increasing our understanding of the genetic architecture of KC may provide new avenues for prevention and treatment. We first conducted a series of genome-wide association studies (GWAS) of KC across three European ancestry datasets from Australia, Europe and USA, and used linkage disequilibrium (LD) Score regression (LDSC) to estimate their pairwise genetic correlations. We employed a multiple-trait approach to map genes across the combined set of KC GWAS (total N = 47 742 cases, 634 413 controls). We also performed meta-analyses of BCC and SCC separately to identify trait specific loci. We found substantial genetic correlations (generally 0.5-1) between BCC and SCC suggesting overlapping genetic risk variants. The multiple trait combined KC GWAS identified 63 independent genome-wide significant loci, 29 of which were novel. Individual separate meta-analyses of BCC and SCC identified an additional 13 novel loci not found in the combined KC analysis. Three new loci were implicated using gene-based tests. New loci included common variants in BRCA2 (distinct to known rare high penetrance cancer risk variants), and in CTLA4, a target of immunotherapy in melanoma. We found shared and trait specific genetic contributions to BCC and SCC. Considering both, we identified a total of 79 independent risk loci, 45 of which are novel.

The Roles of YAP/TAZ and the Hippo Pathway in Healthy and Diseased Skin

Skin is the largest organ of the human body. Its architecture and physiological functions depend on diverse populations of epidermal cells and dermal fibroblasts. Reciprocal communication between the epidermis and dermis plays a key role in skin development, homeostasis and repair. While several stem cell populations have been identified in the epidermis with distinct locations and functions, there is additional heterogeneity within the mesenchymal cells of the dermis. Here, we discuss the current knowledge of how the Hippo pathway and its downstream effectors Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) contribute to the maintenance, activation and coordination of the epidermal and dermal cell populations during development, homeostasis, wound healing and cancer.

A panel of biomarkers for skin squamous cell carcinoma: various functional entities and differential responses to resveratrol

In contrast to the highly malignant melanoma, skin squamous cell carcinoma (SCC) usually presents with lower morbidity. However, its incidence has been alarmingly rising worldwide and is a public health burden, let alone the current SCC cancer classification scheme is inadequate. Due to its features of progressing along different pathologic stages, early detection of precancerous lesions with accurate molecular markers would be desirable for cancer prevention and treatment. In the present study, using immunohistochemical staining of 85 clinical samples, we profiled the expression of a panel of ten proteins from five functional divisions implicated in SCC development, i.e. cytokeratins, intercellular molecules, chaperone proteins, transcription factors, and mitochondrial redox enzymes. The differential alterations of the proteins in SCC cell lines SCL12 and COLO16, upon resveratrol therapy, were also examined by immunocytochemistry (ICC). Our data reveal that, while all these proteins show significant correlation with cancer initiation and/or progression, a comprehensive panel encompassing a range of biologic functions, instead of a single marker, will provide prognostic value in SCC diagnosis and management. Additionally, the strong correlation among the proteins with cancer stages implies their distinct roles in SCC pathogenesis and contributions to the therapeutic effects of resveratrol, which is demonstrated in the resveratrol-sensitive COLO16 cells, but not in the resveratrol-resistant SCL12 cells.

Consensus Guidelines on the Use of Superficial Radiation Therapy for Treating Nonmelanoma Skin Cancers and Keloids

Background: The use of superficial radiation therapy (SRT) has experienced a renaissance for treating nonmelanoma skin cancers (NMSCs) and recurrent keloids; however, published treatment guidelines are lacking. Objective: The objective of this work was to provide consensus guidelines on the use of SRT for treating NMSC and recurrent keloids based on a review of the literature and expert opinion. Methods and Materials: A search of the medical literature was performed to obtain published information on the use of SRT for review. A group of qualified dermatologists convened to discuss their views on the use of SRT for the treatment of NMSCs and recurrent keloids. The various guidelines were considered to have consensus based on a supermajority two-thirds vote. The final consensus guidelines are thus based on the medical literature, when available, and expert opinions. Results: Agreement on consensus guidelines was reached for numerous aspects of SRT use, including appropriate tumor types for SRT; anatomical areas suitable for SRT; energy, fractions, and scheduling recommendations for SRT; use of SRT in the presence of comorbidities; safety factors; and treatment recommendations for recurrent keloids, based the literature and on both the opinions of the expert group and a survey of experienced users. Conclusion: Consensus was reached that SRT is a safe and effective treatment for basal cell and squamous cell carcinomas and should be considered as the first-line form of radiation treatment. Postsurgical treatment of keloid excision suture lines with SRT significantly reduces keloid recurrence rates.

Treatment of Actinic Keratoses Facilitates Dermatoscopic Diagnosis of Early Basal Cell Carcinoma: A Case Report and Review

Chronic exposure to ultraviolet radiation induces gradual changes in cutaneous morphology, which with increasing damage leads to the appearance of cancerous skin lesions. Among them, basal cell carcinomas (BCCs) and actinic keratoses (AKs) are the most common entities. Both lesions often develop as two separate lesions in a single individual at a conspicuous distance, close proximity or as collision lesions, which are characterized by the coexistence of both cancers in the same anatomical site. Collision lesions in which AK precisely overlies BCC is a rarely reported entity. We report a case where the presence of BCC was dermatoscopically detected after an overlying AK was treated with topical chemotherapy, thus indicating that treatment of AK allows better visualization of other underlying malignancies.

Effect of cladribine tablets on lymphocyte reduction and repopulation dynamics in patients with relapsing multiple sclerosis

BACKGROUND

Immune reconstitution therapies (IRT) for patients with multiple sclerosis are used for short, intermittent treatment periods to induce immune resetting and allow subsequent treatment-free periods. Cladribine tablets are postulated to be an IRT that causes selective and transient reductions in CD19⁺ B cells and T cells, followed by reconstitution of adaptive immune function.

OBJECTIVE

To characterize long-term lymphocyte count changes in pooled data from the 2-year CLARITY and subsequent 2-year CLARITY Extension studies, and the PREMIERE registry (Long-term CLARITY cohort).

METHODS

Data from patients randomized to placebo (n = 435) or cladribine tablets 10 mg (MAVENCLAD^®; 3.5 mg/kg cumulative dose over 2 years, referred to as cladribine tablets 3.5 mg/kg; n = 685) in CLARITY or CLARITY Extension, including time spent in the PREMIERE registry were pooled to provide long-term follow-up data. The study investigated absolute lymphocyte counts (ALC) up to 312 weeks and B and T cell subsets up to 240 weeks after the first dose, in patients receiving placebo or cladribine tablets 3.5 mg/kg administered as two short (4 or 5 days) weekly treatments at the start of months 1 and 2 in each treatment year, followed by no further active treatment.

RESULTS

Treatment with cladribine tablets 3.5 mg/kg resulted in selective reductions in B and T lymphocytes. Lymphocyte recovery began soon after treatment in each of years 1 and 2. Median ALC recovered to the normal range and CD19⁺ B cells recovered to threshold values by week 84, approximately 30 weeks after the last dose of cladribine tablets in year 2. Median CD4⁺ T cell counts recovered to threshold values by week 96 (approximately 43 weeks after the last dose of cladribine tablets in year 2). Median CD8⁺ cell counts never dropped below the threshold value.

CONCLUSION

These results show the dynamics of lymphocyte count changes following treatment with cladribine tablets 3.5 mg/kg. The immune cell repopulation results provide further evidence that cladribine tablets may represent a form of IRT.

Actinic keratosis and imiquimod: a review of novel carriers and patents

INTRODUCTION

Actinic keratosis is one of the most common disorder characterized by erythematic and generally attached scaly lesions which are present either alone or in clusters. World Health Organization defines actinic keratosis as a common intraepidermal neoplasm of sun-damaged skin, characterized by variable atypia of keratinocytes.

AREAS COVERED

At the beginning of the 20th century, a new immunomodulator molecule, imiquimod, appears in the market for the treatment of actinic keratosis but suffers from the pitfalls of the conventional approach of dosage form preparation including high dose, poor stability and more side effects. The present article attempts to compile the scatter information related to actinic keratosis and imiquimod at one place. The special emphasis will be made on the information available in various research articles and patents with respect to the efforts made for overcoming shortcomings associated with imiquimod by novel drug delivery or other approaches.

EXPERT OPINION

The conventional drug delivery systems are unsuccessful to improve the actinic keratosis. The patient acceptance and compliance with these treatments are generally poor due to associated side effects, poor cosmetic outcomes and high costs. Therefore, several available and reported novel therapeutic approaches are being developed in order to provide better action.

Translation regulation in skin cancer from a tRNA point of view

Protein synthesis is a central and dynamic process, frequently deregulated in cancer through aberrant activation or expression of translation initiation factors and tRNAs. The discovery of tRNA-derived fragments, a new class of abundant and, in some cases stress-induced, small Noncoding RNAs has perplexed the epigenomics landscape and highlights the emerging regulatory role of tRNAs in translation and beyond. Skin is the biggest organ in human body, which maintains homeostasis of its multilayers through regulatory networks that induce translational reprogramming, and modulate tRNA transcription, modification and fragmentation, in response to various stress signals, like UV irradiation. In this review, we summarize recent knowledge on the role of translation regulation and tRNA biology in the alarming prevalence of skin cancer.

T Regulatory Cell Subpopulations Associated with Recent Ultraviolet Radiation Exposure in a Skin Cancer Screening Cohort

UV radiation (UVR) causing DNA damage is a well-documented risk factor for nonmelanoma skin cancer. Although poorly understood, UVR may also indirectly contribute to carcinogenesis by promoting immune evasion. To our knowledge, we report the first epidemiological study designed to investigate the association between quantitative measures of UVR, obtained using a spectrophotometer, and circulating T regulatory (Treg) cells. In addition to total Treg cells, the proportion of functionally distinct Treg cell subsets defined by CD45RA and CD27 phenotypic markers, graded expression of FOXP3 and CD25, and those expressing cutaneous lymphocyte-associated Ag and the chemokine receptor CCR4 were enumerated in 350 individuals undergoing routine skin cancer screening exams and determined not to have prevalent skin cancer. No associations were identified for UVR exposure or the overall proportion of circulating Treg cells; however, Treg cell subpopulations with an activation-associated phenotype, CD45RA^-/CD27^-, and those expressing cutaneous homing receptors were significantly positively associated with UVR. These subpopulations of Treg cells also differed by age, sex, and race. After stratification by natural skin tone, and adjusting for age and sex, we found that spectrophotometer-based measures of UVR exposure, but not self-reported measures of past sun exposure, were positively correlated with the highest levels of these Treg cell subpopulations, particularly among lighter-skinned individuals. Findings from this large epidemiologic study highlight the diversity of human Treg cell subpopulations associated with UVR, thus raising questions about the specific coordinated expression of CD45RA, CD27, CCR4, and cutaneous lymphocyte-associated Ag on Treg cells and the possibility that UVR contributes to nonmelanoma skin cancer carcinogenesis through Treg cell-mediated immune evasion.

Skin cancer detection using non-invasive techniques

Skin cancer is the most common form of cancer and is globally rising. Historically, the diagnosis of skin cancers has depended on various conventional techniques which are of an invasive manner. A variety of commercial diagnostic tools and auxiliary techniques are available to detect skin cancer. This article explains in detail the principles and approaches involved for non-invasive skin cancer diagnostic methods such as photography, dermoscopy, sonography, confocal microscopy, Raman spectroscopy, fluorescence spectroscopy, terahertz spectroscopy, optical coherence tomography, the multispectral imaging technique, thermography, electrical bio-impedance, tape stripping and computer-aided analysis. The characteristics of an ideal screening test are outlined, and the authors pose several points for clinicians and scientists to consider in the evaluation of current and future studies of skin cancer detection and diagnosis. This comprehensive review critically analyses the literature associated with the field and summarises the recent updates along with their merits and demerits.