Pathogenesis of Keratinocyte Carcinomas and the Therapeutic Potential of Medicinal Plants and Phytochemicals

The Role of Radiation, Immunotherapy, and Chemotherapy in the Management of Locally Advanced or Metastatic Cutaneous Malignancies

INTRODUCTION

Skin cancer impacts a significant proportion of the population. While surgical management is often the mainstay of treatment, advanced or metastatic cutaneous malignancies require additional local and/or systemic therapies.

METHODS

A review of the literature was performed studying the use of radiation therapy, chemotherapy, and immunotherapy for locally advanced or metastatic cutaneous malignancies.

RESULTS

A summary of the present literature on the management of locally advanced or metastatic cutaneous malignancies is presented across cutaneous head and neck basal cell carcinoma, squamous cell carcinoma, melanoma, and Merkel cell carcinoma. The addition of multidisciplinary therapies to resection is often associated with improved outcomes.

CONCLUSION

The management of cutaneous head and neck malignancies requires an approach integrating multiple specialties, to optimize outcomes and minimize toxicities.

Correlating dermatoscopic features with immunohistochemical markers in basal cell carcinoma: a comprehensive analysis of 100 cases in Caucasian population

Background

Basal Cell Carcinoma (BCC) is the most common form of skin cancer, characterized by its low metastatic potential yet considerable diversity in clinical and dermatoscopic presentation. Advances in dermatoscopy have significantly improved the early detection of BCC, revealing specific patterns that guide diagnosis and management. Parallelly, immunohistochemical markers have been explored for their potential to elucidate the underlying tumor biology and prognosis, with particular focus on angiogenesis, melanocytic activity, and lymphangiogenesis.

Objective

This study aims to investigate the correlations between dermatoscopic features and the immunohistochemical expressions of CD34, CD31, Melan-A, and D2-40 in BCC, through a comprehensive analysis of 100 cases We sought to determine whether visual dermatoscopic patterns correlate with the molecular characteristics defined by immunohistochemical staining, potentially enhancing diagnostic accuracy.

Methods

A total of 100 cases of clinically and histopathologically confirmed BCC were prospectively analyzed, employing standard dermatoscopic techniques for lesion evaluation and immunohistochemical staining for CD34, CD31, Melan-A, and D2-40 to assess tumor angiogenic potential, melanocytic activity, and lymphangiogenesis. The study was conducted with adherence to ethical standards and informed consent from all participants.

Results

Dermatoscopic examination revealed a variety of vascular patterns and pigmented features across different BCC anatomical locations. However, the comprehensive correlation analysis predominantly found a lack of significant associations between dermatoscopic appearances and expressions of the targeted immunohistochemical markers, with the notable exception of a correlation between observed hemorrhage and the Melan-A marker.

Conclusions

The lack of significant correlations between dermatoscopic features and immunohistochemical marker expressions in BCC suggests that the biological behavior and angiogenic, melanocytic, and lymphangiogenic activities within BCC lesions may be influenced by factors beyond those assessed in this study. Despite the exploratory nature of these findings, they underscore the complexity of BCC biology and highlight the need for further research incorporating additional markers and advanced imaging techniques.

Skin Development and Disease: A Molecular Perspective

Skin, the largest organ in the human body, is a crucial protective barrier that plays essential roles in thermoregulation, sensation, and immune defence. This complex organ undergoes intricate processes of development. Skin development initiates during the embryonic stage, orchestrated by molecular cues that control epidermal specification, commitment, stratification, terminal differentiation, and appendage growth. Key signalling pathways are integral in coordinating the development of the epidermis, hair follicles, and sweat glands. The complex interplay among these pathways is vital for the appropriate formation and functionality of the skin. Disruptions in multiple molecular pathways can give rise to a spectrum of skin diseases, from congenital skin disorders to cancers. By delving into the molecular mechanisms implicated in developmental processes, as well as in the pathogenesis of diseases, this narrative review aims to present a comprehensive understanding of these aspects. Such knowledge paves the way for developing innovative targeted therapies and personalised treatment approaches for various skin conditions.

Tonsillar squamous cell carcinoma in a male Lhasa Apso

Squamous cell carcinoma (SCC) and more specifically tonsillar SCC are generally regarded as locally invasive with various rates of metastasis. A 13-year-old male Lhasa Apso was referred to the clinic with an unusual mass on his left tonsil and abnormal lumps under the tongue. The dog's food and water intake, breathing and heart rates, body temperature, capillary refill time, and blood tests were normal. A biopsy of abnormal tissue and immunohistochemical analysis were performed. Histopathological and immunohistochemical evaluations confirmed the basaloid SCC. Some treatments like surgery, radiotherapy, and chemotherapy are used to treat a specific tumor or area of the body. However, in this particular case, chemotherapy was not administered. Considering that dogs with tonsillar cancer generally have a poor to guarded prognosis and a short life expectancy, this case was euthanized after one year with the owner's consent due to the significant tumor enlargement.

In Silico and In Vitro Studies on an Asymmetrical Porphyrin Derivative with Therapeutic Potential in Skin Disorders

For developing novel photosensitizers with therapeutic potential in non-malignant and malignant cutaneous disorders, the unsymmetrical porphyrin, 5-(2-hydroxy-3-methoxyphenyl)-10, 15, 20-tris-(4-carboxymethylphenyl) porphyrin, was evaluated in silico and in vitro. The cellular uptake of the investigated porphyrin and its ability to perform photodynamic therapy were investigated in terms of the viability, proliferation, and necrosis of human HaCaT keratinocytes and human Hs27 skin fibroblasts, in correlation with the predictions regarding diffusion through cell membranes, ADMET profile (absorption, distribution, metabolism, elimination, toxicity), and potential pharmacological mechanism. Molecular docking and 250 ns molecular dynamics simulations revealed that P5.2 has the potential to form a relatively stable complex with the carbonic anhydrase IX catalytic site, the lowest predicted free energy of binding (MM/PBSA) being -39.097 kcal/mol. The results of the in vitro study showed that P5.2 is incorporated within 24 h in the investigated cells, especially in HaCaT keratinocytes, indicating its photosensitizing ability. Nevertheless, P5.2 does not exert significant cytotoxicity in "dark" conditions. In turn, PDT induced a decrease in the number of metabolically active HaCaT keratinocytes within 24 h, accompanied by a 4-fold increase in lactate dehydrogenase release, indicating its ability to perform PDT in human skin cells. The experimental results suggest that the asymmetrical porphyrin is a promising candidate theranostics agent for skin disorders.

Investigation of Epilobium hirsutum L. Optimized Extract's Anti-Inflammatory and Antitumor Potential

Epilobium hirsutum L., commonly known as hairy willowherb, is a perennial herbaceous plant native to Europe and Asia. In Romania, the Epilobium genus includes 17 species that are used in folk medicine for various purposes. This study aimed to investigate the anti-inflammatory and antitumor potential of the optimized extract of Epilobium hirsutum (EH) in animal models. The first study investigated the anti-inflammatory properties of EH optimized extract and the model used was carrageenan-induced paw inflammation. Wistar rats were divided into three groups: negative control, positive control treated with indomethacin, and a group treated with the extract. Oxidative stress markers, cytokine levels, and protein expressions were assessed. The extract demonstrated anti-inflammatory properties comparable to those of the control group. In the second study, the antitumor effects of the extract were assessed using the tumor model of Ehrlich ascites carcinoma. Swiss albino mice with Ehrlich ascites were divided into four groups: negative, positive treated with cyclophosphamide (Cph), Group 3 treated with Cph and EH optimized extract, and Group 4 treated with extract alone. Samples from the ascites fluid, liver, and heart were analyzed to evaluate oxidative stress, inflammation, and cancer markers. The extract showed a reduction in tumor-associated inflammation and oxidative stress. Overall, the EH optimized extract exhibited promising anti-inflammatory and antitumor effects in the animal models studied. These findings suggest its potential as a natural adjuvant therapeutic agent for addressing inflammation and oxidative stress induced by different pathologies.

Efficacy and safety of tirbanibulin 1% ointment in actinic keratoses: Data from two phase-III trials and the real-life clinical practice presented at the European Academy of Dermatology and Venereology Congress 2022

BACKGROUND

The 31st European Academy of Dermatology and Venereology (EADV) Congress took place between 7th and 10th of September 2022 in Milan, Italy.

OBJECTIVES

We report presented clinical data on the efficacy/effectiveness, safety and tolerability of tirbanibulin 1% ointment that has recently been licensed for actinic keratosis (AK) of the face or scalp in adults.

METHODS

Summary of presentations given at the EADV Congress.

RESULTS

Prof. Pellacani presented two post hoc analyses from two phase-III trials with AK patients (NCT03285477 [N = 351] and NCT03285490 [N = 351]): A descriptive analysis of medical history, concomitant medications, and safety results confirming a favourable profile for tirbanibulin showing that number of baseline AK lesions was not correlated to severity of local skin reactions. The latter analysis showed that cases of tirbanibulin application site pain or pruritus were few, and most were found to be mild. Prof. Kunstfeld reported six real-life clinical cases in Austria showing good tirbanibulin effectiveness, safety and tolerability for the treatment of new or recurring AK lesions. Results demonstrated that after 2- to 4-month follow-up, tirbanibulin was well tolerated and effective in AK patients. Presentations by Dr. Patel confirmed good outcomes and tolerability of tirbanibulin in Olsen grade 1-2 AK (N = 12) and porokeratosis patients (N = 4) treated once daily for 5 consecutive days in the United Kingdom. Furthermore, real-world experience in solid organ transplant recipients (N = 2) demonstrated effectiveness of tirbanibulin in skin field cancerization treatment. A symposium sponsored by Almirall was conducted during the congress in which Dr. Hadshiew and Dr. Lear brought together their clinical experience in Germany and the United Kingdom respectively. Interesting clinical cases of 5 consecutive days of tirbanibulin treatment compared to other treatments were discussed with attendees, as well as current treatment needs of AK patients.

CONCLUSIONS

This article provides an overview of presentations and symposium discussions, summarizing key phase-III results and real-life clinical experience with tirbanibulin shared by dermatologists across Europe.

Exogenous hormone therapy and non-melanoma skin cancer (keratinocyte carcinoma) risk in women: a systematic review and meta-analysis

Previous studies reported inconsistent results regarding the association between keratinocyte carcinoma (KC) and exogenous hormone therapy. This study aimed to investigate the association between the use of exogenous sex hormones and the risk of KC among women. The databases of PubMed, Ovid Medline, Cochrane, and Web of Science were searched until May 2023. A total of 5293 patients with KC and 106,424 controls were included for analysis. The meta-analysis indicated that oral contraceptives (OC) and hormonal replacement therapy (HRT) use were associated with an increased risk of squamous cell carcinoma (SCC) (OR/RR = 1.25, 95% CI 1.10 to 1.43, I2 = 41.6%, p = 0.080). Subgroup analysis showed that OC use increased the risk of SCC (OR/RR = 1.37, 95% CI 1.15 to 1.63), whereas no significant association was shown between HRT use and risk of SCC (OR/RR = 1.13, 95% CI 0.93 to 1.37). Additionally, OC and HRT use were linked to an increased risk of basal cell carcinoma (BCC) (OR/RR = 1.16, 95% CI 1.09 to 1.25, I2 = 30.1%, p = 0.188). Further subgroup analysis suggested both OC and HRT use were associated with an increased risk of BCC (OC: OR/RR = 1.13, 95% CI 1.01 to 1.25; HRT: OR/RR = 1.19, 95% CI 1.09 to 1.30). In conclusion, our findings support the hypothesis that the risk of KC among women may be affected by the use of exogenous hormones.

Microbiota, Oxidative Stress, and Skin Cancer: An Unexpected Triangle

Mounting evidence indicates that the microbiota, the unique combination of micro-organisms residing in a specific environment, plays an essential role in the development of a wide range of human diseases, including skin cancer. Moreover, a persistent imbalance of microbial community, named dysbiosis, can also be associated with oxidative stress, a well-known emerging force involved in the pathogenesis of several human diseases, including cutaneous malignancies. Although their interplay has been somewhat suggested, the connection between microbiota, oxidative stress, and skin cancer is a largely unexplored field. In the present review, we discuss the current knowledge on these topics, suggesting potential therapeutic strategies.

Advances in Photodynamic Therapy for the Treatment of Actinic Keratosis and Nonmelanoma Skin Cancer: A Narrative Review

Photodynamic therapy (PDT) with photosensitization using 5-aminolevulinic acid (ALA) [including a nanoemulsion (BF-200 ALA)] is approved in the USA for the treatment of actinic keratoses (AKs); another derivative, methyl aminolevulinate, is not approved in the USA but is used in Europe. For AK treatment, the photosensitizer may be applied to individual AK lesions or, depending on treatment regimen, to broader areas of sun-damaged skin to manage field cancerization, although not all products are approved for field treatment. ALA-PDT and photosensitizers have also been used off-label for the treatment of nonmelanoma skin cancers, primarily basal cell carcinomas (BCCs) and cutaneous squamous cell carcinomas (cSCC). Advantages of PDT include potentially improved cosmesis and patient satisfaction; disadvantages include pain and duration of treatment. Alternative illumination approaches, including intense pulsed light as well as pulsed-dye lasers, have also been used successfully. Pretreating the affected tissue or warming during incubation can help to increase photosensitizer absorption and improve therapeutic efficacy. Combinations of multiple treatments are also under exploration. Reducing incubation time between photosensitizer application and illumination may significantly reduce pain scores without affecting treatment efficacy. Substituting daylight PDT for a conventional illumination source can also reduce pain without compromising efficacy. The objective of this narrative review is to describe current and ongoing research in the use of topical photosensitizers and modified light delivery regimens to achieve improved therapeutic outcomes with less toxicity in patients with AK, cSCC, BCC, and field cancerization.

Molecular Mechanisms and Targeted Therapies of Advanced Basal Cell Carcinoma

Among human cutaneous malignancies, basal cell carcinoma is the most common. Solid advances in unveiling the molecular mechanisms of basal cell carcinoma have emerged in recent years. In Gorlin syndrome, which shows basal cell carcinoma predisposition, identification of the patched 1 gene (PTCH1) mutation was a dramatic breakthrough in understanding the carcinogenesis of basal cell carcinoma. PTCH1 plays a role in the hedgehog pathway, and dysregulations of this pathway are known to be crucial for the carcinogenesis of many types of cancers including sporadic as well as hereditary basal cell carcinoma. In this review, we summarize the clinical features, pathological features and hedgehog pathway as applied in basal cell carcinoma. Other crucial molecules, such as p53 and melanocortin-1 receptor are also discussed. Due to recent advances, therapeutic strategies based on the precise molecular mechanisms of basal cell carcinoma are emerging. Target therapies and biomarkers are also discussed.

Non-melanoma skin cancers: physio-pathology and role of lipid delivery systems in new chemotherapeutic treatments

Non-melanoma carcinoma has high incidence rates and has two most common subtypes: basal cell carcinoma and squamous cell carcinoma. This type of carcinoma is usually not fatal; however, it can destroy sensory organs such as the nose, ears, and lips. The treatment of these injuries using non-invasive methods is thus strongly recommended. Some treatments for non-melanoma carcinoma are already well defined, such as surgery, cryosurgery, curettage and electrode section, and radiotherapy; however, these conventional treatments cause inflammation and scarring. In the non-surgical treatment of non-melanoma carcinoma, the topical administration of chemotherapeutic drugs contributes for an effective treatment with reduced side effects. However, the penetration of anticancer drugs in the deeper layers of the skin is required. Lipid delivery systems (liposomes, solid lipid nanoparticles, nanostructured lipid carriers) have been developed to overcome epidermal barrier of the skin and to allow the drugs to reach tumor cells. These lipid nanoparticles contribute to control the release profile of the loaded chemotherapeutic drugs, maintaining their stability and increasing death of tumor cells. In this review, the characteristics of non-melanoma carcinoma will be discussed, describing the main existing treatments, together with the contribution of lipid delivery systems as an innovative approach to increase the effectiveness of topical therapies for non-melanoma carcinomas.

The Modulatory Influence of Plant-Derived Compounds on Human Keratinocyte Function

The plant kingdom is a rich source of secondary metabolites with numerous properties, including the potential to modify keratinocyte biology. Keratinocytes are important epithelial cells that play a protective role against various chemical, physical and biological stimuli, and participate in reactive oxygen scavenging and inflammation and wound healing processes. The epidermal cell response may be modulated by phytochemicals via changes in signal transduction pathways. Plant extracts and single secondary compounds can possess a high antioxidant capacity and may suppress reactive oxygen species release, inhibit pro-apoptotic proteins and apoptosis and activate antioxidant enzymes in keratinocytes. Moreover, selected plant extracts and single compounds also exhibit anti-inflammatory properties and exposure may result in limited production of adhesion molecules, pro-inflammatory cytokines and chemokines in keratinocytes. In addition, plant extracts and single compounds may promote keratinocyte motility and proliferation via the regulation of growth factor production and enhance wound healing. While such plant compounds may modulate keratinocyte functions, further in vitro and in vivo studies are needed on their mechanisms of action, and more specific toxicity and clinical studies are needed to ensure their effectiveness and safety for use on human skin.