Tobacco smoking is associated with cutaneous squamous cell carcinoma but not with basal cell carcinoma or melanoma in adult subjects at risk of skin cancer: A cross-sectional study.

Introduction: The relationship between tobacco smoking and cutaneous photodamage or malignancies is still unclear. In addition to smoking, both ultraviolet radiation and immunosuppression have an impact on carcinogenesis. The purpose was to study the association of smoking with cutaneous photoaging, actinic keratosis (AK), skin cancers, and pigment cell nevi in adult subjects at risk of any type of skin cancer.

Spectrum of malignant and premalignant skin lesions in 505 adult subjects at risk of skin cancers.

Patients at risk of skin cancers can develop varying types of cutaneous malignancies. However, some subjects may develop only one type of lesion. In this cross-sectional study, the spectrum of premalignant (PM) and malignant skin lesions and their risk factors were studied.

Increased expression of complement C3c, iC3b, and cells containing CD11b or CD14 in experimentally induced psoriatic lesion.

Psoriasis is a chronic inflammatory skin disease with a characteristic isomorphic reaction, i.e. the Köbner reaction, induced by slight epidermal trauma.

Expression of mast cell tryptase and immunoglobulin E is increased in cutaneous photodamage: implications for carcinogenesis.

Mast cells, their serine proteinase tryptase, and immunoglobulin E (IgE) can be involved in cutaneous carcinogenesis. To study the association of tryptase and IgE cells with photodamage and skin cancers 385 adult patients (201 males, 184 females, 75 with immunosuppression) at risk of any type of skin cancer were examined. Skin biopsies were taken from the sun-protected medial arm and from the photodamaged dorsal forearm skin followed by immunohistochemical staining for tryptase and IgE.

FoxP3-Positive Cells and Their Contacts with Mast Cells Are Highly Increased in Basal Cell Carcinoma.

Introduction: The cells of the immune system are thought to contribute to the development of skin cancers, such as basal cell carcinoma (BCC). One possible mechanism may be the interaction between mast cells and regulatory T cells (Tregs), resulting in immunosuppression.

Methods: Fresh-frozen biopsies from the lesional and nonlesional skin of 16 patients with BCC were processed for the enzymehistochemical staining of mast cell tryptase, immunohistochemical staining of FoxP3 (a marker of Tregs) as well as for the double-staining method to label tryptase+ cells and FoxP3+ cells on the same cryosection.

Corticotropin-releasing hormone receptor-1 is increased in mast cells in psoriasis and actinic keratosis, but not markedly in keratinocyte skin carcinomas.

Corticotropin-releasing hormone receptor-1 (CRH-R1) is expressed in human mast cells, but its role in skin diseases is unknown. By using a sequential double-staining technique, the mast cell expression of CRH-R1 was investigated in biopsies from lesional and non-lesional skin samples of patients with actinic keratosis (AK), basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and psoriasis. Dermal tryptase mast cells expressed CRH-R1 immunoreactivity in the non-lesional skin in all patient groups.

The prognostic and predictive role of tumor-infiltrating lymphocytes (FoxP3 + and CD8 +) and tumor-associated macrophages in early HER2 + breast cancer.

Purpose: In HER2-positive (HER2 +) breast cancer, tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs) may influence the efficacy of the HER2-antibody trastuzumab and the patient's outcome. In this HER2 + patient cohort, our aim was to study the numbers of FoxP3 + regulatory TILs and CD8 + cytotoxic TILs, their correlations with CD68 + and CD163 + TAMs, and the prognostic and predictive value of the studied factors.

Methods: We evaluated 139 non-metastatic HER2 + breast cancer patients operated between 2001 and 2008.

Patients with a history of atopy have fewer cutaneous melanomas than those without atopy: a cross-sectional study in 496 patients at risk of skin cancers.

The connection between atopy and skin cancers may be related to the stimulation of protective immune response, for example, through autoreactive immunoglobulin-E (IgE), or to the predisposition to carcinogenesis through chronic inflammation. The aim of this study was to investigate whether a past or present atopic disorder is associated with cutaneous photodamage, pigment cell nevi and skin cancers. For this, adult subjects at risk of any type of skin cancer (aged 21-79 years, 250 males, 246 females, 94 with immunosuppression) were examined for past or present malignancies in skin and extracutaneous site (ECS), photodamage, nevi, past or present atopic disorder in skin or mucus membranes, and possible other cancer-related factors.

Mast cell chymase is in contact with melanoma cells and it detaches melanoma cells from the substratum .

Background: Mast cell chymase, a chymotryptic serine proteinase, is a powerful enzyme that may liberate adherent tumor cells thereby promoting tumor spread.

Methods: This study investigated interactions between cells containing immunoreactive chymase and melanoma cells in 101 melanoma and 50 nevus specimens as well as used recombinant human (rh)-chymase and WM115 and G361 primary melanoma cell lines in culture.

Results: Rh-chymase at low concentration (0.

Regular use of vitamin D supplement is associated with fewer melanoma cases compared to non-use: a cross-sectional study in 498 adult subjects at risk of skin cancers.

There are conflicting results on the role of vitamin D system in cutaneous carcinogenesis. Therefore, it was investigated whether the use of oral vitamin D supplements associates with photoaging, actinic keratoses, pigment cell nevi, and skin cancers. In this cross-sectional study, 498 adults (aged 21-79 years, 253 males, 245 females, 96 with immunosuppression) subjects at risk of any type of skin cancer were examined, and possible confounding factors were evaluated.

Pinoresinol stimulates keratinocyte proliferation and downregulates TNF-α secretion in peripheral blood mononuclear cells: An experimental in vitro study.

Background And Aims: Natural coniferous resins are used in traditional medicine for the treatment of skin wounds. Coniferous wood resins ("callus" resin) are a mixture of abietic (resin) acids, lignans such as pinoresinol, and -coumaric acid. The wound-healing properties of resins are thought to be related to their antimicrobial properties, but also to their effects on cell proliferation and inflammation.

Malignant and in situ subtypes of melanoma are associated with basal and squamous cell carcinoma and its precancerous lesions.

Background: Patients with cutaneous malignant melanoma (CMM) are at increased risk of non-melanoma skin cancers (NMSCs) and possibly precancerous lesions.

Objectives: To analyse the association between CMM and not only NMSCs but also precursor lesions, actinic keratosis (AK) and Bowen disease (BD).

Materials & Methods: The Finnish Cancer Registry data was used to calculate the age-standardized incidence ratio during 2000-2013 for basal (BCC) and squamous (SCC) cell carcinoma in patients with CMM.

Sequential Increase in Complement Factor I, iC3b, and Cells Expressing CD11b or CD14 in Cutaneous Vasculitis.

Mast cells contribute to the pathogenesis of cutaneous vasculitis through complement C3 that is cleaved to C3b and then to iC3b by complement factor I. The receptor of iC3b, CD11b, is expressed on neutrophils and monocytes and CD14 on monocytes. Their role in vasculitis is obscure.

Survival from cutaneous malignant melanoma is improving, but is it because of a trend in decreasing melanoma thickness or the advent of new 'revolutionary' therapeutics?

Zamagni 2022; 187:52–63.

Case: Unexpected development of severe penicillin allergy and review of literature.

A 54-year-old man developed a severe anaphylactic penicillin allergy after 16 years and 5 standard erysipelas treatments by intravenous benzylpenicillin and/or oral phenoxymethylpenicillin without any symptoms of allergy. It is recommended to analyze specific IgE antibodies for phenoxymethylpenicillin, benzylpenicillin, amoxicillin, and cefaclor to select an appropriate antibiotic.

High regional mortality due to malignant melanoma in Eastern Finland may be explained by the increase in aggressive melanoma types.

Background: A regional skin cancer prevention program in Eastern Finland revealed a relatively high age-standardized mortality due to malignant melanoma during 2013-2017. An explanation for this is needed.

Purpose: To analyse the 543 melanoma samples in 524 subjects collected during 2000-2013 at Kuopio University Hospital and reposited in the Biobank of Eastern Finland.

Association of Elevated Serum Tryptase with Cutaneous Photodamage and Skin Cancers.

Introduction: Mast cells and their major protein, the serine proteinase tryptase, can be involved in cutaneous photodamage and carcinogenesis. The serum test of tryptase (S-tryptase) measures total tryptase protein (active tryptase and inactive protryptases), and S-tryptase is elevated in a variety of diseases, for example, in mastocytosis and α-tryptasemia.

Objectives: The objective of this study is to study whether S-tryptase is a marker of cutaneous photodamage and carcinogenesis.

Mast Cells in Human Cutaneous Neurofibromas: Density, Subtypes, and Association with Clinical Features in Neurofibromatosis 1.

Background: Cutaneous neurofibromas (cNFs) are hallmarks of neurofibromatosis 1 (NF1) and cause the main disease burden in adults with NF1. Mast cells are a known component of cNFs. However, no comprehensive characterization of mast cells in cNFs is available, and their contributions to cNF growth and symptoms such as itch are not known.

Mast Cells and Sensory Nerves Contribute to Neurogenic Inflammation and Pruritus in Chronic Skin Inflammation.

The intimate interaction between mast cells and sensory nerves can be illustrated by the wheal and surrounding flare in an urticarial reaction in human skin. This reaction is typically associated with an intense itch at the reaction site. Upon activation, cutaneous mast cells release powerful mediators, such as histamine, tryptase, cytokines, and growth factors that can directly stimulate corresponding receptors on itch-mediating sensory nerves.

Mast Cells Are a Marked Source for Complement C3 Products That Associate with Increased CD11b-Positive Cells in Keratinocyte Skin Carcinomas.

By using immunohistochemistry and antibodies that identify complement C3c (in C3 and C3b) or CD11b receptor, we report that the proportion C3c mast cells and the number of CD11b cells are increased in basal cell carcinoma (BCC). Instead, only CD11b cells are increased in squamous cell carcinoma/Bowen's disease, and only slightly so in actinic keratosis. Only C3c mast cells are increased in psoriasis.

Mast cell chymase degrades fibrinogen and fibrin.

Background: The accumulation of immunoreactants and fibrinoid necrosis of postcapillary vessel walls are common pathological features of cutaneous immune complex vasculitis. In more advanced lesions, these immunoreactants are subject to proteolysis. Mast cell chymase is a powerful enzyme that can degrade several substrates including the extracellular matrix.

Mast cell-neural interactions contribute to pain and itch.

Mast cells are best recognized for their role in allergy and anaphylaxis, but increasing evidence supports their role in neurogenic inflammation leading to pain and itch. Mast cells act as a "power house" by releasing algogenic and pruritogenic mediators, which initiate a reciprocal communication with specific nociceptors on sensory nerve fibers. Consequently, nerve fibers release inflammatory and vasoactive neuropeptides, which in turn activate mast cells in a feedback mechanism, thus promoting a vicious cycle of mast cell and nociceptor activation leading to neurogenic inflammation and pain/pruritus.