Effects of topical tretinoin on dysplastic nevi.

PURPOSE: As potential precursors of melanoma and markers of increased melanoma risk, dysplastic nevi are suitable targets of strategies for melanoma chemoprevention. We report the results of a pilot study of topical retinoic acid in patients with dysplastic nevi. PATIENTS AND METHODS: Five male patients with dysplastic nevi applied tretinoin to half of the back for 6 months. Baseline photographs of dysplastic nevi were compared with posttreatment photographs and assessed for morphologic change. At study completion, each subject had four nevi excised from the treated side and four from the untreated side of the back. Biopsies were histologically evaluated for the presence of dysplasia. RESULTS: All patients developed signs of irritation as a result of treatment. One patient was not compliant with treatment due to skin irritation. The four compliant patients showed significant decreases in the clinical atypia of treated lesions, with concomitant fading and even disappearance of many treated nevi. Histologically, only four of 16 treated nevi met histologic criteria for dysplasia, in comparison to 13 of 16 untreated nevi. CONCLUSION: These results suggest that there is concomitant clinical and histologic improvement in a significant percentage of dysplastic nevi treated with topical tretinoin. However, the utility of topical tretinoin for chemoprevention of melanoma is limited by difficulty of application and associated inflammation. While new strategies in chemoprevention of melanoma are explored, sun protection and assiduous avoidance of sunburn must remain the mainstay of melanoma prevention.

Discordance of SSA/Ro and SSB/La cellular antigens in synchronized cells.

SSA/Ro and SSB/La are soluble cellular proteins to which antibodies are frequently produced in patients with Sjögren's syndrome and systemic lupus erythematosus. In this investigation, we examined anti-SSA/Ro and anti-SSB/La staining patterns on synchronized WiL2 cells and mixed lymphocyte culture cells using monospecific antisera. In addition to its presence in the nucleoplasm, the SSB/La antigen was highly concentrated in the nucleolus of cells during the late G1 and early S phase and is thus cell cycle-related. In contrast, the SSA/Ro antigen was found to be independent of cell cycle, showing a nuclear speckled pattern in all phases. Blocking experiments indicated that free SSB/La is responsible for the nucleolar staining, whereas the combination of both SSA/Ro and SSB/La determines the nucleoplasmic speckled staining pattern.

UVB induction of epithelial tumors in human skin using a RAG-1 mouse xenograft model.

To examine the effects of chronic ultraviolet light on human epidermal cells, we grafted white human skin onto recombinase activating gene-1 knockout mice. We found previously that the maximal concentration of ultraviolet B radiation (290-320 nm) tolerated by human skin xenografts was 500 J per m2 when given three times weekly. One hundred and fifty-eight grafted mice were randomized and observed for a median of 10 mo in four groups: (i) no treatment; (ii) one treatment with the chemical carcinogen dimethyl-(a)benzanthracene; (iii) ultraviolet B three times weekly; and (iv) a combination of dimethyl-(a)benzanthracene and ultraviolet B. Approximately half of the skin specimens treated with ultraviolet B developed superficial milia and epidermal cysts. Grafts contained up to seven milia lesions between 4 and 8 mo after initiation of treatment, whereas the number of larger epidermal cysts was rarely more than two. Milia and cysts developed in the skin regardless of pigmentation or tanning. Actinic keratoses arose in 9% of grafts treated with ultraviolet B alone and in 19% of grafts treated with the combination of dimethyl-(a)benzanthracene and ultraviolet B. Invasive squamous cell carcinomas developed in 10% of grafts after combined dimethyl-(a)benzanthracene and ultraviolet B treatment and lesions were restricted to skin grafts that did not tan. These findings demonstrate that (i) development of ultraviolet-induced lesions can be experimentally accelerated in human skin, (ii) xenografted recombinase activating gene-1 deficient mice are superior to severe combined immunodeficiency disease mice for chronic ultraviolet B studies, and (iii) benign cystic tumors and squamous cell carcinomas are caused by ultraviolet B.

Apoptosis induction of ultraviolet light A and photochemotherapy in cutaneous T-cell Lymphoma: relevance to mechanism of therapeutic action.

The anti-tumor action of many chemotherapeutic agents has recently been attributed to the induction of apoptosis in the malignant cell population. In this study, we investigated the ability of extracorporeal photopheresis (ExP) and in vitro PUVA (8-methoxy-psoralen + ultraviolet A) therapy to induce apoptosis in peripheral blood mononuclear cells from Sezary syndrome patients and normal controls. Flow cytometric analysis of ExP- or PUVA-treated peripheral blood lymphocytes demonstrated two distinct cell populations within 24 h of treatment. One population was similar to untreated controls with the other exhibiting characteristics of apoptotic cell death, i.e., a loss of cell volume and an accompanying increase in cell density. This latter population was comprised of cells with DNA strand breaks as determined by the Tdt-mediated deoxyuridine triphosphate-biotin nick end labeling assay. Apoptosis was also confirmed morphologically by fluorescent and electron microscopy as well as by demonstration of characteristic DNA strand breaks (laddering) using gel electrophoresis. Apoptosis was not observed with 8-methoxypsoralen (< or = 300 ng per ml) alone; however, ultraviolet A alone at doses > or = 2 J per cm2 induced apoptosis in lymphocytes. Peripheral blood T-cell subpopulations of Sezary syndrome patients, including the malignant clone, were equally susceptible to apoptosis subsequent to either photopheresis or PUVA treatment. In contrast, monocytes (CD14+/CD45+) appear to be resistant to apoptosis induction by ExP or PUVA treatment. Moreover, ExP-treated and untreated monocytes phagocytized apoptotic, but not untreated, peripheral blood mononuclear cells. ExP and PUVA have been shown to be efficacious and well-tolerated therapies in the treatment of dermatologic diseases and transplant rejection. These data suggest that induction of apoptosis may be an important event for therapeutic efficacy.

Subcutaneous panniculitis-like T-cell lymphoma: clinicopathologic, immunophenotypic, and genotypic analysis of alpha/beta and gamma/delta subtypes.

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is an uncommon cutaneous lymphoma that has been proposed as a distinct clinicopathologic entity, but studies of SPTCL are limited. We studied the clinicopathologic, immunophenotypic, and genetic features of 11 SPTCLs. All cases had a variable admixture of pleomorphic small, medium, or large lymphocytes and histiocytes infiltrating the subcutis in a lobular panniculitis-like pattern. A granulomatous reaction was seen in three cases and erythrophagocytosis in four. Karyorrhexis and fat necrosis were present in all cases. Angioinvasion was seen in seven SPTCLs; four had areas of coagulation necrosis. All cases expressed T-cell-associated antigens (CD3epsilon, CD45RO, or CD43) and T-cell receptors (TCR); nine expressed alphabeta TCRs and two expressed gammadelta TCRs. T-cell receptor-gamma, TCRbeta, or TCRdelta genes were clonally rearranged in 8 of 10 cases studied. Both gammadelta SPTCLs expressed Vdelta2+ TCRs and were CD4-, CD8- and CD56+. CD56 was negative in seven of nine alphabeta SPTCLs and inconclusive in the other two. Six of nine alphabeta SPTCLs were CD8+; the CD4/CD8 phenotypes were indeterminate in the other three. Cytolytic granule-associated proteins were expressed by all SPTCLs (11 of 11 were TIA-1+, 4 of 4 were perforin+). In situ hybridization for Epstein-Barr virus-encoded RNA (EBER-1) was negative in all cases. Most patients responded to systemic chemotherapy or local radiation therapy. Seven patients are alive: four without disease (19-73 months) and three with disease (32-72 months); four died: three of disease (3-25 months) and one without disease (42 months). We conclude that SPTCLs are clonal, EBV-, cytotoxic T-cell lymphomas derived from alphabeta T-cells or gammadelta T-cells. The gammadelta SPTCLs appear to be preferentially derived from the Vdelta2+ subset. Subcutaneous panniculitis-like T-cell lymphoma may be rapidly fatal or indolent; local therapy may be appropriate for some patients.

Progression-related expression of beta3 integrin in melanomas and nevi.

The expression of the beta3 integrin subunit was investigated in 130 fixed, paraffin-embedded specimens of human melanomas and nevi using two different monoclonal antibodies. Expression was not observed in melanocytes and was absent or low in most nevi. In primary melanomas, expression was absent or low in the nontumorigenic radial growth phase, which includes the classes of in situ and microinvasive melanomas. In contrast, expression was high in the tumorigenic or vertical growth phase compartment of many primary melanomas and in most metastatic melanomas. Expression patterns were similar with the two antibodies, SSA6 and SAP, and was membrane-related as well as cytoplasmically expressed. In those nevi that reacted focally, the reactivity tended to occur in the dermal component of neurotized nevi, and in Spitz nevi, where the reactivity was stronger and more diffuse. A few dysplastic nevi showed focal reactivity of the junctional component. These results are consistent with tumor progression-related expression of the beta3 integrin, which is expressed in melanocytic tumors as the alphavbeta3 integrin, having affinity for matrix molecules, including vitronectin and fibronectin. In all melanomas, and in the subset of tumorigenic vertical growth phase melanomas, expression increased with thickness (P < .01). For this reason, and because ligation of this integrin has been shown in vitro to have several properties that may be related to the malignant phenotype, it is likely that expression of this marker may have prognostic value. However, because of its consistent and strong expression in Spitz nevi, the diagnostic utility of this marker will likely be limited.

Comparison of IgG subclass autoantibodies in patients with systemic lupus erythematosus and subacute cutaneous lupus erythematosus.

Circulating antinuclear antibodies and in vivo bound immunoglobulins at the dermal-epidermal junction are frequently seen in patients with lupus erythematosus. The present study was designed to examine the distribution of the IgG subclasses of in vivo skin bound IgG and circulating antinuclear antibodies (ANA) in patients with systemic lupus erythematosus (SLE) or subacute cutaneous lupus erythematosus (SCLE). Immunofluorescence studies on skin biopsies showed IgG1 to be the predominant IgG subclass in SCLE patients, present in 20 of 21 (95%) of the specimens. IgG2 was present in 4 patients (19%), IgG3 in 1 (5%), and IgG4 in 7 (33%). The frequencies of IgG2, IgG3, and IgG4 skin staining were significantly higher in the seven SLE patients who were studied: IgG1 in 7/7 (100%), IgG2 in 7/7 (100%) and IgG4 in 6/7 (86%). Immunoblot analysis for the IgG subclasses was performed on serum of 29 patients with SCLE who had antibodies to SSA/Ro antigen. Twenty-seven (93%) of these patients were positive for IgG1 anti-SSA/Ro antibody, while the frequencies for IgG2, IgG3, and IgG4 anti-SSA/Ro were very low. These studies indicate that there is a difference in the IgG subclass antibody response in patients with SLE and SCLE. The presence of more than one subclass antibody may be indicative of systemic disease.

Antinuclear matrix antibody. Hidden antinuclear antibody in patients with connective tissue diseases.

A total of 435 serum samples from patients with different rheumatic diseases were screened for the presence of autoantibody to nuclear matrix components by indirect immunofluorescence on 0.1 mol/L HCl extracted HEp-2 cell and WiL2 cell substrates. A total of 28 specimens were positive in this assay. Eighteen of them were from patients with systemic lupus erythematosus (18 of 250), 2 from patients with rheumatoid arthritis (2 of 115), and 8 from patients with mixed connective tissue disease (8 of 10). Antigenic material for this antibody is resistant to DNase, partially sensitive to RNase, and sensitive to trypsin. This indicates that the antigen is composed of protein and possibly RNA. In immunoblot analysis, sera positive for this antibody in indirect immunofluorescence assay recognized different peptides. This suggests that protein peptides are the major antigenic material.

Melanoma induction in a hairless mouse with short-term application of dimethylbenz[a]anthracene.

Melanomas have been induced in hamsters and guinea pigs with short-term, low dose applications of dimethylbenz [a]anthracene (DMBA) alone. In mice, however, melanoma induction has required either croton oil or ultraviolet radiation promotion in addition to DMBA. In this study, we report the development of a malignant melanoma, with metastases, in a hairless mouse after six applications of 0.25% DMBA alone. At sacrifice, a large primary tumour with characteristics of intralesional transformation was present, along with numerous pigmented macules and papules. Metastases were present in lymph nodes and lungs. There was a marked similarity between this melanoma and its precursor lesions and those seen in an earlier, Weiser-Maple guinea pig model, which, in turn, resembled human melanoma.

The early and intermediate precursor lesions of tumor progression in the melanocytic system: common acquired nevi and atypical (dysplastic) nevi.

Intermediate lesions of melanocytic tumor progression are potential precursors, simulants, and risk markers of melanoma. The clinical, public health, and biologic significance of intermediate lesions warrants their continued recognition and study, although improved schemata for their clinical and histological coding are needed. Blurred boundaries are inherently problematic to the categorization of lesions occurring along a stepwise pathway of increasing clinical and histological atypia. Nevertheless, the concepts of melanocytic dysplasia and of radial growth phase (in situ and microinvasive) melanoma are important to the classification of intermediate lesions of melanocytic tumor progression. Conceptually, these lesions are clearly separable from early and late lesions and from one another, and there is evidence that criteria distinguishing them can be reproducibly applied. Analysis of these intermediate lesions suggests that they represent responses to events (perhaps mutational) induced by ultraviolet light in constitutionally hypersensitive individuals, supporting epidemiological data that implicate sunlight as an etiologic agent for most melanomas. The continuing rigorous application of the methodologies of epidemiology and basic science to the study of these lesional steps will likely lead to the recognition of biologic markers to better distinguish benign from malignant melanocytic lesions.

Neoplastic progression and prognosis in melanoma.

Most melanomas evolve through an initial stage known as radial growth phase (RGP), encompassing in situ and microinvasive malignancies in which the probability of cure approaches 100%. At the present time, despite a shift toward earlier recognition of melanoma, by the time of diagnosis roughly 70% of melanomas have evolved to a point, known as vertical growth phase (VGP) or tumorigenic melanoma, at which cure is not certain, and prognosis depends upon certain attributes of the neoplasm and the host. Attempts have been made to assemble these attributes into prognostic models to permit estimation of the probability of cure for individuals and for groups of patients. Attributes that have been identified as independent prognostic variables include thickness of the primary neoplasm, the numbers of mitotic figures, and the presence of tumor-infiltrating lymphocytes (TIL). Other biologically important prognostic variables are on the horizon, and some will likely be based on molecules (markers) expressed on neoplastic cells that show functional significance in mechanisms of metastasis.

Oral pigmentation representing Laugier-Hunziker syndrome.

Oral pigmentation is seen fairly commonly in dermatologic practice. Several conditions must be considered in the differential diagnosis. We present a patient whose condition highlights the clinical syndrome known as Laugier-Hunziker and provides the opportunity to review the clinical course, pathologic features, and literature of this uncommon syndrome.

Scurvy and panniculitis: a case report.

In most western countries, scurvy has become a rare clinical entity. However, it may still be encountered in selected situations. It can mimic connective tissue disease, because of multiorgan involvement. Panniculitis has not previously been described in association with scurvy.