Human papilloma viruses (HPV) are a small group of non-enveloped viruses belonging to the Papillomaviridae family with strong similarities to polyoma viruses. The viral particles consist of a genome in the form of a circular double-stranded DNA, encompassing eight open reading frames, as well as a non-enveloped icosahedral capsid. HPV infection is considered the most common sexually transmitted disease in both sexes and is strongly implicated in the pathogenesis of different types of cancer. ‘High-risk’ mucosal HPV types, predominantly types 16, 18, 31, 33 and 35, are associated with most cervical, penile, vulvar, vaginal, anal, oropharyngeal cancers and pre-cancers. Screening for HPV is necessary for the prognosis and for determining treatment strategies for cancer. Novel HPV markers, including proteomic and genomic markers, as well as anti-papillomavirus vaccines are currently available. The aim of this comprehensive review was to thoroughly present the updated information on virus development, cancer occurrence, treatment and prevention strategies, in an attempt to shed further light into the field, including novel research avenues.
The process of melanin synthesis and distribution is called melanogenesis, a process that is based on melanocytes present among the basal cells of the epidermis. Pigments formed in melanocyte melanosomes are then stored in the basal layer of epidermal cells, as well as in dermal macrophages, which become melanophores. From the embryological point of view, melanocytes derive from the melanoblasts of the neural crest, from where they migrate during the first months of life into the skin, eye, cochlea, bone, peripheral nervous system, heart and adipose tissue. The melanic pigments, eumelanin and pheomelanin, are the final product of complex biochemical reactions starting from the amino acid L-tyrosine. Melanin has a major role in skin homeostasis through the photoprotection it offers from the harmful effect of ultraviolet radiation. Melanin absorbs and/or reflects ultraviolet radiation but is also involved in the neutralizing process of free radicals and reactive oxygen species. Pigmentogenesis is a dependent oxygen process and is controlled by intrinsic factors (genetic and hormonal) as well as extrinsic factors (ultraviolet radiation). Melanogenesis is stimulated by stimulant melanocytic hormone, adrenocorticotropin hormone, estrogens and progesterone. The present review aimed to provide a summary of recent data about melanogenesis physiology.
In vivo reflectance confocal microscopy (RCM) is a modern, non-invasive imaging technique, which allows for real-time examination of the upper layers of the skin at a resolution similar to that of classic microscopy. In addition, it has the advantage of real-time evaluation of blood flow and dynamic monitoring of cutaneous changes while preserving tissue integrity. The present study reported on the in vivo RCM technique as an objective method for the noninvasive assessment of psoriasis vulgaris that is potentially applicable in clinical studies and in monitoring the evolution of lesions under treatment. In psoriasis lesions, RCM virtual horizontal sections at the level of the dermo-epidermal junction featured numerous and prominent dermal papillae that were not surrounded by bright rings of basal cells. Micromorphological examination of the lesions using this technique revealed that mean values of the section area, the perimeter and the Feret's diameter of the dermal papillae were significantly higher in psoriatic lesions than in normal skin. An increased number of capillary vessels per lesional dermal papilla as compared to healthy skin was observed. Furthermore, micromorphological parameters of dermal capillaries were increased in psoriatic skin. These observations point to the utility of in vivo RCM as a promising technique for the non-invasive diagnosis of psoriasis vulgaris, for monitoring the evolution of lesions at a micromorphological level under various treatments and for gaining a better understanding of the pathophysiological processes that occur in the evolution of this disease.
Tumors of the central nervous system are the most prevalent complications of melanoma, especially in the late stage of disease. Melanoma, lung and breast cancer are the leading cause of secondary tumors in the brain, the majority of them having a poor outcome. Brain dissemination is developed in half of stage IV melanomas and these cases can increase up to 75%, having a major impact on the quality of life. This review will focus on recent findings that provide new ways to potentially prevent brain metastases in malignant melanoma. The key of these findings is based on the heterogeneity of the melanoma and of the brain metastases at genetic levels. This new era of technologies provides new tools in understanding the dissemination mechanisms of malignant cells. The cellular and molecular changes, the immune status of the patient and the blood-brain barrier permeability are key regulators of cancer cell dissemination. Understanding these mechanisms can render new hope in preventing brain metastases by focusing on melanoma and new pharmacologic approaches. Contents
Uveal melanoma is a rare condition accounting for only 5% of all primary melanoma cases. Still, it is the most frequently diagnosed primary intraocular malignant tumor in adults. Almost 90% of the tumors involve the choroid and only a small percentage affects the ciliary body or the iris. There is a consistent difference in incidence between different regions with individuals of northern European descent having a significantly higher risk as compared to Hispanics, Asians, and Blacks. Among the many risk factors, mutations in the G protein subunit alpha Q (GNAQ) or G protein subunit alpha 11 (GNA11) genes and different receptors are highly suggestive. While iris melanoma can easily be noticed by the patient itself or diagnosed at a routine slit-lamp evaluation, a consistent percentage of posterior uveal tumors are incidentally diagnosed at funduscopic evaluation as they can evolve silently for years, especially if located in the periphery. Uveal melanoma classifications rely on the tumor size (thickness and basal diameter) and also on intraocular and extraocular extension. The differential diagnosis with pseudomelanomas is carried out according to the tumor aspect and position. Iris melanoma has a better prognosis and a lower mortality rate as compared to choroidal melanoma that has a much higher rate of metastasis (50% of the patients) and a subsequent limited life expectancy from 6 to 12 months. While conservative therapeutic options for the primary tumor, relying on different surgical excision techniques and/or irradiation therapies, offer good local tumor control, the treatment options for metastatic disease, although numerous, are still inadequate in preventing a fatal outcome.
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