Nicotine and biochanin A, but not cigarette smoke, induce anti-inflammatory effects on keratinocytes and endothelial cells in patients with Behçet's disease.

During periods of smoking, patients with Behçet's disease have less oral aphthae than in abstinence. To elucidate this observation, human keratinocytes and dermal microvascular endothelial cells (HMEC-1) were incubated with serum of 20 patients with Behçet's disease and 20 healthy controls for 4 hours. Maximum non-toxic concentrations were determined and the cells were further treated with 6 microM nicotine, 3.3% cigarette smoke extract (CES), 100 microM biochanin A, and 6.25/12.5 microM pyrrolidine dithiocarbamate alone and in combinations for 24 hours. Serum IL-8 levels of patients were significantly lower than those of controls. However, after 4 hours incubation with patients' sera, IL-8 release by both cell types was markedly increased when compared with the corresponding serum levels. The levels of IL-6 and vascular endothelial growth factor (VEGF) release were after 4 hours similar with the corresponding levels in serum. IL-1 was not detected. Nicotine significantly decreased IL-8 and -6 release by HMEC-1 maintained in both patients' and controls' sera, but only IL-6 release by keratinocytes maintained in patients' sera. VEGF release by both cells was markedly increased after nicotine treatment in either serum. CES significantly decreased IL-8 release and increased production of VEGF in keratinocytes maintained in patients' serum. The phytoestrogen biochanin A alone and in combination with nicotine further decreased the secretion of IL-8, -6, and VEGF in all experimental settings. Our data support a specific anti-inflammatory effect of nicotine on keratinocytes and endothelial cells maintained in the serum of patients with Behçet's disease. Moreover, biochanin A is likely to exhibit similar and even more profound results than nicotine.

Efficient TRAIL-R1/DR4-mediated apoptosis in melanoma cells by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL).

Therapy resistance is crucial for the high mortality of melanoma. The death ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) bears high potential as a new anticancer agent, as binding to the death receptors TRAIL receptor 1/death receptor 4 (TRAIL-R1/DR4) or TRAIL receptor 2/death receptor 5 (TRAIL-R2/DR5) triggers apoptosis in most cancer cells. For melanoma, however, only a weak responsiveness of primary cultures was reported, and in particular the role of DR4 was neglected. For evaluating melanoma susceptibility, we studied the functionality of DR4 and DR5 in melanoma cells as well as their expression in vivo. DR5 was consistently expressed in melanoma cell lines, whereas DR4 was found in only 2/7 cell lines. High sensitivity to TRAIL-induced apoptosis was characteristic for DR4-positive melanoma cells, whereas DR4-negative cells showed less and delayed response or were resistant. The use of selective DR4/DR5 blocking antibodies unequivocally proved the prevalent role of DR4 in those melanoma cells, where it was expressed. The significance of these data for the in vivo situation was finally evaluated by immunohistochemistry, which proved pronounced expression of DR4 as well as of DR5 in melanoma primary tumors. Thus, DR4 expression in vivo and the high efficiency of DR4-mediated apoptosis may suggest reassessment of the suitability of TRAIL and especially of DR4-based strategies for melanoma treatment.

Selective induction of apoptosis in melanoma cells by tyrosinase promoter-controlled CD95 ligand overexpression.

Induction of apoptosis has been demonstrated previously by overexpression of CD95 ligand (CD95L) in cultured human melanoma cells. For in vivo approaches based on CD95L, however, targeted expression is a prerequisite and tyrosinase promoters have been considered for selection. Luciferase reporter gene assays performed for a representative panel of melanoma cell lines characterized by strong (SK-Mel-19), moderate (SK-Mel-13, MeWo), weak (A-375), and missing expression (M-5) of endogenous tyrosinase revealed high tyrosinase promoter activities in SK-Mel-19, SK-Mel-13, and MeWo, but only weak activities in A-375 and M-5 as well as in non-melanoma cell lines. After transfection of a CMV promoter CD95L expression construct, melanoma cells were found highly sensitive, as compared with non-melanoma cells. By applying a tyrosinase promoter CD95L construct, apoptosis was selectively induced in SK-Mel-19, SK-Mel-13, MeWo as well as in A-375, which was characterized by high CD95 surface expression and high sensitivity to agonistic CD95 activation. M5 and non-melanoma cell lines remained uninfluenced. Also, resistance to agonistic CD95 activation seen in MeWo characterized by weak CD95 surface expression was overcome by overexpression of CD95L. Our investigations provide evidence that tyrosinase promoter CD95L constructs may be of value for selective induction of apoptosis in therapeutic strategies for melanoma.

Early TCR-beta and TCR-gamma PCR detection of T-cell clonality indicates minimal tumor disease in lymph nodes of cutaneous T-cell lymphoma: diagnostic and prognostic implications.

The lymph nodes are generally the first extracutaneous manifestation in patients with cutaneous T-cell lymphoma (CTCL); however, their early involvement is difficult to assess. The aim of our study was to define the diagnostic and prognostic value of T-cell clonality analysis for a more precise assessment of lymph node involvement in CTCL. T-cell clonality was determined by 2 independent polymerase chain reaction (PCR) assays, namely a recently developed T-cell receptor-beta (TCR-beta) PCR technique as well as an established TCR-gamma PCR. T-cell clonality was found in 22 of 22 lymph nodes with histologically detectable CTCL involvement as well as in 7 of 14 histologically noninvolved dermatopathic lymph nodes. The clonal T-cell populations in the lymph nodes were in all cases identical to those detected in the corresponding skin lesions, identifying them as the tumor cell population. T-cell clonality was not found in any of the 12 dermatopathic lymph nodes from 12 patients with inflammatory skin diseases. Clonal T-cell detection in 7 of 14 dermatopathic lymph nodes of patients with CTCL was associated with limited survival (74 months; confidence interval [CI], 66-82 months) as in patients with histologically confirmed lymph node involvement (41 months; CI, 35-47 months), whereas all patients without T-cell clonality in the lymph nodes (7 patients) were alive at the last follow-up. Thus, T-cell clonality analysis is an important adjunct in differentiating benign dermatopathic lymphadenitis from early CTCL involvement.

Proliferation of human melanoma cells is under tight control of protein kinase C alpha.

Exponential proliferation of human melanoma cells has been associated with low levels of protein kinase C (PKC)-alpha. The aim of the present study was to investigate the functional relationship between PKC-alpha and melanoma cell proliferation. Treatment of human melanoma cells with the selective PKC inhibitor Ro-31-8220 resulted in a significant increase of cell proliferation as measured by (3)H-thymidine incorporation and a fluorometric microassay. In addition, phosphorothioate antisense-oligodeoxynucleotides (ODNs) to PKC-alpha enhanced DNA-synthesis of human melanoma cells. Furthermore, microinjection and transient transfection of melanoma cells with PKC-alpha decreased their proliferation, as shown by the reduction of nuclear staining with the proliferation marker Ki-67. The presented data demonstrate a cause-effect relationship between PKC-alpha and melanoma cell growth, whereby PKC-alpha reversely influences the rate of cell proliferation.

Dacarbazine but not temozolomide induces phototoxic dermatitis in patients with malignant melanoma.

Ten patients with malignant melanoma and phototoxic reactions under dacarbazine or 5-(3,3-dimethyl-1-triazeno) imidazole-4-carboxamide (DTIC) chemotherapy were investigated. All patients available for testing showed increased ultraviolet A-sensitivity (n = 5); patch testing revealed no type IV allergies (n = 6). In 5 patients intravenous DTIC was replaced by oral temozolomide, and no phototoxicity occurred. Temozolomide may represent an alternative for patients with DTIC-induced phototoxic skin reactions.

Verrucous carcinoma of the axilla: case report and review.

BACKGROUND: Verrucous carcinoma, a variant of squamous cell carcinoma, is distinct from squamous cell carcinoma in morphology and behavior. It preferentially occurs on the oropharyngeal mucosa, the urogenital mucosa, and the soles. In contrast to its malignant clinical picture, the tumor grows locally invasive but is histologically benign and metastasizes rarely. METHODS: We report the uncommon occurrence of a large verrucous carcinoma on apparently uninvolved skin in the right axilla in a 47-year-old male. RESULTS: Histologic examination reveals a cauliflower-like tumor consisting of deep invaginated epidermal proliferation with rabbit burrow-like, keratin-filled sinus formations; the basement membrane, however, remains intact. Immunohistology showed positivity for pancytokeratin (KL-1) and cytokeratin (CK) 18 and negativity for CK7, and assessment of the proliferative activity of the tumor cells revealed low percentage of Ki-67 expression. Furthermore, there were only scattered cells expressing p53 or bcl-2. Polymerase chain reaction excluded the presence of human papillomavirus. After complete excision, no signs of recurrence occurred over a follow-up period of three years. CONCLUSION: Verrucous carcinoma should be distinguished from typical squamous cell carcinoma. The clinicopathological features, differential diagnosis, and therapy are discussed here together with the molecular biologic aspects of the tumor.

CD95/Fas signaling in human melanoma cells: conditional expression of CD95L/FasL overcomes the intrinsic apoptosis resistance of malignant melanoma and inhibits growth and progression of human melanoma xenotransplants.

The significance of CD95/Fas ligand expression by melanoma cells has remained a controversial matter in recent years. On the other hand, CD95 activation may represent a powerful tool for eliminating tumor cells. Here, we demonstrate expression of CD95 in 15/17 human melanoma cell lines analysed, but complete lack of CD95 ligand (CD95L). Overexpression of CD95 in a tetracycline-inducible expression system enhanced melanoma cell sensitivity to CD95 ligation but was unable to trigger apoptosis by itself. In clear contrast, all melanoma cells tested responded with increased apoptosis to conditional expression of CD95L (2-10-fold), both after transient and after stable transfection. Activation of caspase-8, Bid cleavage, cytochrome c release and caspase-3 activation followed after CD95L induction indicating a functional CD95-signaling cascade. CD95L was also able to enhance the proapoptotic effect of chemotherapeutics applied in parallel. Nude mouse experiments revealed that tumorigenicity was lost when melanoma xenografts were triggered to express CD95L. In addition, further progression of pre-existing melanomas was inhibited and even regression was seen after induction of CD95L expression. Due to these data, transfection of CD95L proofs as a highly efficient tool against melanoma cells in vitro and in vivo, and targeted expression of CD95L may thus represent a suitable strategy for melanoma therapy.

Conditional expression of exogenous Bcl-X(S) triggers apoptosis in human melanoma cells in vitro and delays growth of melanoma xenografts.

The Bcl-2-related proteins Bcl-X(L) and Bcl-X(S) represent alternative splice products and exert opposite activities in the control of apoptosis, but their significance for melanoma is not yet clear. Applying the tetracycline-inducible expression system Tet-On, we found overexpression of Bcl-X(S) by itself sufficient to induce apoptosis in vitro in stably transfected human melanoma cell lines. Combination with proapoptotic agents such as etoposide, pamidronate, and ceramide resulted in additive proapoptotic effects, whereas Bcl-X(L) protected from apoptosis caused via CD95/Fas stimulation. In nude mice growth of melanoma xenotransplants derived from stably transfected cells was significantly reduced after induction of Bcl-X(S) by doxycycline. Our results indicate that Bcl-X proteins are of major importance for control of apoptosis in malignant melanoma.

Atypical generalized eruptive histiocytosis associated with acute monocytic leukemia.

Histiocytoses are diseases caused by proliferation of either dendritic cells/Langerhans cells or of monocytes/macrophages. Generalized eruptive histiocytosis belongs to the cutaneous non-Langerhans cell histiocytoses and is a rare monocyte-macrophage proliferative disorder that usually follows a benign clinical course. We present the case of a 59-year-old man who presented with a 7-month history of progressively developing erythematous macules and slightly elevated papules widely distributed over the trunk, neck, face, and thighs. Ultrastructurally, no Birbeck granules were observed, and immunochemistry did not reveal any S-100 protein or CD1a antigen in any of the lesional cells, excluding Langerhans cell histiocytosis. In addition, the histiocytic infiltrate in the skin of our patient was shown to strongly express MS-1 high molecular weight protein, a marker described as highly characteristic for cutaneous non-Langerhans cell histiocytoses. Bone-marrow smear examination and flow cytometric analysis revealed monocytic leukemia. This is the second report of generalized eruptive histiocytosis associated with acute monocytic leukemia. We discuss the differential diagnoses of the clinical picture and stress that this benign cutaneous disorder may indicate an underlying hematologic malignancy.

Common clonal T-cell origin in a patient with T-prolymphocytic leukaemia and associated cutaneous T-cell lymphomas.

An unusual course was observed in a patient with indolent T-prolymphocytic leukaemia (T-PLL) who subsequently developed mycosis fungoides (Mf), lymphomatoid papulosis (LyP) and cutaneous CD30+ anaplastic large cell lymphoma (ALCL). Polymerase chain reaction analysis demonstrated identical monoclonal T-cell receptor-beta and -gamma gene rearrangements in all the different clinical entities. Furthermore, cytogenetic studies revealed the same aberrant clone with trisomy of chromosome 8 in T-PLL and ALCL cells. This unique observation suggests that in T-PLL, the leukaemic cells might undergo secondary transformation, subsequently resulting in different phenotypes of cutaneous T-cell lymphoma.