Faculty Bibliography

Urokinase-type plasminogen activator (uPA) is thought to be an important mediator in the proteolytic degradation of extracellular matrix components observed in a wide variety of normal physiological and pathological conditions. However, the phenotype of a recently developed strain of urokinase-deficient (uPA-/-) mice appears to be normal when maintained under ideal nonstressful conditions. We report an outbreak of botryomycosis, an unusual staphylococcal infection, in a colony of uPA-deficient mice. A detailed histological examination of these uPA-deficient animals also revealed a variety of previously unreported phenotypic abnormalities such as pleuritis and the effacement of lymphoid follicles in the regional lymph nodes and spleen. Additional phenotypic abnormalities such as dystrophic calcifications and rectal prolapse were also observed in the uPA-deficient population. These abnormalities were also noted in ostensibly healthy uPA-deficient animals. Botryomycosis did not affect a colony of wild-type (uPA+/+) animals maintained concurrently under identical conditions in the same room. The peculiar predisposition of the uPA-deficient animals to this rare bacterial infection and the development of phenotypic abnormalities associated with the targeted disruption the uPA gene suggests that uPA contributes significantly to the cutaneous microenvironment and is additional evidence of the extensive involvement of the plasminogen activators in mammalian physiology

A critical requirement to use tumor antigens as vaccines is that they stimulate CD8+ T cell responses. In this study, we tested the ability of a shed, polyvalent, melanoma antigen vaccine to induce such responses to the melanoma-associated antigens, MAGE-3 and MART-1/Melan-A. Fifteen HLA-A2+ patients with resected malignant melanoma were immunized to the vaccine sc every 2-3 weeks x 4, and monthly thereafter. CD8+ T cells in peripheral blood reacting to HLA-A2 restricted epitopes on MAGE-3 (FLWGPRALV) and/or MART-1/Melan-A (AAGIGILTV) were quantitated directly using a filter spot assay at baseline and following 4 immunizations. Vaccine immunization induced CD8+ T cells reacting specifically to one or both of these antigens in 9 (60%) patients. These cells were CD8+ and HLA-A2 restricted, as reactivity was abrogated by monoclonal antibodies to CD8 and to class I HLA, but not by anti-CD4. The CD8+ T cells were specifically directed to these antigens, as they did not react to the same targets pulsed with a control HLA-A2 restricted peptide recognized by T cells. All responding patients remained recurrence-free during a follow-up of 12-21 months, whereas melanoma recurred within 3-5 months in non-responders. The differences in outcome were unrelated to differences in disease-severity or overall immunological competence between CD8+ T cell responders and non-responders. These results demonstrate that a polyvalent vaccine can stimulate a CD8+ T cell response to MAGE-3 and MART-1/Melan-A in humans, and suggest that the responses are protective and surrogate markers of vaccine efficacy. (C) American Society of Clinical Oncology 1997

Thirty-nine mammographically detected, (M-detected) small invasive carcinomas of the breast (< or = 5 mm) were compared with 78 consecutive clinical cancers (> or = 10 mm) for a variety of morphological and biological markers of prognostic importance. There were more tubular carcinomas in the M-detected group (12.8% v 3.8%), but this did not reach statistical significance. Incidences of other histological types were similar. The types of associated in situ component were similar in the two groups. M-detected cancers were of lower overall grade (P < .001), lower architectural and nuclear grades (P = .0164 and P < .0001 respectively), and had fewer mitotic cells (P < .0001). None showed positive lymph nodes (P < .0001). Estrogen and progesterone receptor expression was similar in both groups. M-detected cancers expressed p53 nuclear protein less frequently than clinical cancers (P = .0398), had lower levels of microvessel density (P = .0001), and were more often diploid (P = .0131). S-phase of diploid tumors in the two groups was similar, but S-phase of aneuploid tumors was lower in the M-detected group (P = .0057). Ki67 expression was lower in M-detected cancers (P < .0001). In conclusion, M-detected small breast cancers, although invasive, represent an evolutionary phase of breast cancer that generally lacks morphological and biologic markers of aggressive behavior. The presence or absence of these markers, collectively, may explain the influence of tumor size on survival in patients with breast cancer

Evidence suggests that the plasminogen activators (PAs), in particular urokinase-type PA (uPA), play a pivotal role in tumor invasion and metastasis. We studied the contribution of the PAs to the malignant phenotype through the chemical induction of melanocytic neoplasms in uPA-deficient mice. Primary tumors were induced and promoted concurrently in 35 uPA-/- deficient and 35 uPA+/+ wild-type mice using a single application of 7,12-dimethylbenz(a)anthracene followed by repetitive applications of croton oil. Animals were sacrificed at 60-day intervals for 1 year. At necropsy, the four largest pigmented lesions in each animal were excised, characterized histologically, and evaluated microscopically for evidence of invasion. The regional lymph nodes, lungs, and solid abdominal visceral organs were sectioned and examined microscopically for evidence of metastatic disease. Cellular blue nevi were induced in 100% of uPA-/- and uPA+/+ promoted animals. Although a reduction in the radial and vertical progression of these lesions was noted in the uPA-deficient mice compared with the wild-type group, more than 95% of cellular blue nevi induced in both groups of animals invaded the underlying tissues. These lesions did not metastasize to the regional lymph nodes. Malignant melanoma arose in 5 of 35 (14.3%) of promoted wild-type mice. These tumors were locally aggressive, produced tissue-type PA, but were not metastatic to the regional nodes, lungs, or abdominal viscera. These results indicate that the invasive capability of melanocytic lesions may depend more on tissue-type PA than uPA activity. No melanomas were induced in the uPA-/- mice. The resistance of the uPA -/- strain to melanoma induction suggests that uPA contributes to malignant progression. We propose that the absence of uPA negatively affects tumorigenesis by decreasing the liberation and availability of growth factors such as basic fibroblast growth factor

Pigmented lesions of the nail bed, especially without a history of trauma, represent a diagnostic challenge to the clinician. These lesions are often categorized as melanonychia striata (MS), which refers to any linear tan-brown-black pigmentation of the nail bed. The differential diagnosis of MS includes subungual hematomas, onchomycosis nigricans, junctional nevi, melanoma in situ (MIS), and malignant melanoma (MM). Our algorithm at the New York University (NYU) Medical Center for the treatment of pigmented lesions of the nail bed is presented. A histopathologic diagnosis with any evidence of melanocytic atypia, however subtle, requires absolute confirmation by complete excision. The absence of a clear margin or recurrence requires total nail bed excision and reconstruction using a full-thickness graft. The diagnosis of MIS is similarly treated. The surgical management of subungual MM is discussed. All cases of MM of the hand treated at NYU were reviewed. In all, 30 patients were treated from 1982 to 1995. Follow-up ranged from 6 months to 13 years. In our series, there were 8 cutaneous and 22 subungual melanomas. There was a marked delay in treatment of both groups, with subungual melanomas more often erroneously treated as other pathology prior to correct diagnosis. The 5-year survival rate was 100% for patients with cutaneous lesions, but only 80% for those with the subungual variety. There was a statistical difference in the depths of the lesions (subungual, 3.68 mm; cutaneous, 1.36 mm) with a p-value of 0.008. The role of elective lymph node dissection in the absence of clinical metastases as well as intraoperative sentinel lymphatic mapping remains controversial and is discussed