Endothelial P-selectin expression is reduced in advanced primary melanoma and melanoma metastasis.

Some malignant tumors induce a cellular immune response that results in the formation of an inflammatory infiltrate and subsequent tumor regression. The infiltrating leukocytes extravasate from the bloodstream after binding to adhesion receptors on the surface of the endothelium. One of these receptors is the P-selectin molecule (CD62P) that is constitutively present on normal capillaries. We observed that P-selectin expression is absent from the microvasculature in advanced primary melanoma and in melanoma metastasis in contrast to benign melanocytic lesions where P-selectin expression was identical to that in normal skin. We suggest that one of the mechanisms by which advanced melanoma lesions evade inflammatory regression operates via a decrease of endothelial P-selectin expression.     

Melanoma growth stimulatory activity in primary malignant melanoma: prognostic significance.

Malignant melanoma (MM) cells do not require all exogenous growth factors of normal melanocytes. It is hypothesized that they make their own growth factors including melanoma growth stimulatory activity (MGSA). Cultured melanoma cells respond to MGSA with increased growth and angiogenesis suggesting a role for MGSA in MM proliferation, differentiation, and progression. We assessed the prognostic significance of MGSA expression in 37 primary MM immunostained for MGSA. Immunostains were graded for intensity (0-3+), percentage of cells immunostained, and location of immunostain (intraepidermal, junctional, or dermal). In addition, 31 melanocytic and 23 dysplastic nevi were similarly studied for MGSA expression. All MM showed the presence of immunostain, 6 (16%) 1+, 12 (32%) 2+, and 19 (51%) 3+. Six (16%) had immunostain in < or = 50% tumor cells, 31 (84%) in >50%. A significant number of MM showed >50% tumor cells staining at the dermal-epidermal junction compared with intraepidermal staining (P <.0001). Intensity and amount of immunostain did not correlate with Clark's or Breslow's level. During a mean follow-up of 60 months (range: 5-101) on 27 patients, there were 4 local recurrences, 6 distant metastases, and 10 deaths. MGSA expression was not of prognostic significance with regard to survival (overall, disease free), or local recurrence or distant metastasis in primary MM. MGSA expression was similar in benign melanocytic and dysplastic nevi. Strong diffuse expression was noted in the junctional component of all junctional and most compound nevi. The dermal component consistently expressed less or no (in 45% of intradermal nevi) MGSA. MGSA expression does not correlate with prognosis in MM. Increased expression of MGSA at the dermal-epidermal junction in nevi and MM may indicate a role for MGSA in early local growth, before development of atypia.     

Spitzoid malignant melanoma with lymph-node metastasis

Distinction of spitzoid malignant melanomas (SMM) from Spitz nevi may be difficult or even impossible on the basis of conventional histology. In this report, a patient suffering from a primary lesion diagnosed as a Spitz nevus and a metastatic malignant melanoma approximately 4 years thereafter is described. A diagnosis of SMM was made subsequently upon review of the primary lesion. In the present analysis, we used comparative genomic hybridization (CGH) to define markers characteristic of SMM. The primary lesion revealed deletions on chromosomes 6q and 9p. In the metastasis, additional deletions on chromosomes 10p and 10q and gains of chromosome 7 were found. To our knowledge, no chromosomal aberration on chromosome 6 was hitherto demonstrated in benign melanocytic nevi. Findings reported in the literature suggest that human melanoma metastasis suppressor gene maps to 6q. In contrast, losses on chromosome 9p seem to be an early event in the development of melanoma. However, they are not only found in melanomas but are occasionally present in Spitz nevi as well as in atypical nevi. The CGH result with deletion of 6q in this difficult to diagnose primary melanocytic lesion strongly supports the diagnosis of malignant melanoma. To demonstrate the reliability of loss on chromosome 6q as a marker of SMM, a larger number of lesions must be investigated.     

Superficial spreading malignant melanoma with neurosarcomatous metastasis

A case of neurosarcomatous nodal metastasis of superficial spreading malignant melanoma, without primary site desmoplasia or sarcomatous changes, is reported. Of particular interest regarding the metastasis are: the ultrastructural demonstration of numerous cytoplasmic microtubules, absence of premelanosomes, intense immunohistochemical reaction with S-100 protein antibody, and the presence, at the light microscopic level, of extranodal fibrosis. The primary lesion shows a pre-existing benign nevus and features suggestive of lamellar fibroplasia. The origin and histogenesis of melanocytic desmoplasia, in the context of a neural crest progenitor cell, and of lamellar fibroplasia, are discussed.     

Dietary crocin reverses melanoma metastasis

Crocus sativus and its bioactive constituent crocin are well known for anti-tumor potential in different models. However, the efficacy of crocin on in-vivo melanoma metastasis is not yet reported. In this study, melanoma metastatic model was developed by tail vein injection of B16F-10 cells in to C57BL/6 mice. Metastatic mice treated with two different doses of crocin (250 and 500 μg/kg of bodyweight) for 10 days and parameters such as lung metastasis inhibition, mean survival time, lung hydroxyproline, uronic acid and hexosamine levels were analyzed after 21 days of treatment. Then blood was collected and serum gamma glutamyl transpeptidase (g-GGT), sialic acid, tumor necrosis factor alpha (TNF-α), interleukin 10 (IL-10), IL-6, IL-2, and TIMP-1 levels were measured. Further, a lung histological examination was done in crocin treated metastatic mice. Subsequently hallmark metastatic parameters such as matrix metalloproteinases (MMPs), extracellular regulated kinase 2 (ERK2), vascular endothelial growth factor (VEGF), and K-ras gene expression were investigated in the lungs of crocin treated metastatic mice. Further, in-vitro adhesion, invasion and migration of B16F-10 cells were examined after 24 hours of crocin (5 and 10 μg/mL) treatment. Administration of crocin to tumor bearing C57BL/6 mice reduced the lung metastasis by 85%. Elevated levels of hydroxyproline, uronic acid, hexosamine, serum sialic acid and g-GGT in metastatic control were found to be significantly reduced in crocin treated mice. Crocin also inhibited expression of MMP-2, MMP-9, ERK-2, K-ras, and VEGF. Crocin reduced the ability of B16F-10 cells invasion (P < 0.05), migration (P < 0.05) and adhesion by upregulating E-cadherin expression. In conclusion, crocin elicited marked anti-metastatic potential by regulating the metastasis induced biomarkers.     

Metastatic melanoma mimicking primary bronchial melanoma

Primary malignant melanoma of the bronchus is an extremely rare neoplasm. The criteria required to establish a bronchial origin include junctional change and invasion of intact bronchial mucosa by melanoma cells. A case of metastatic melanoma demonstrating such changes is described, so casting doubt on the validity of these criteria.     

The vascular phenotype of melanoma metastasis

Melanoma cells but not normal melanocytes share important cell surface molecules with endothelial cells. From this observation has grown our hypothesis that melanoma and endothelial cells use the same cell surface molecules for invasion but that their intracellular signaling is different allowing the malignant cells dominance over the normal cells. Stromal fibroblasts and endothelial cells communicate with metastatic cells through an interactive network of cell–cell and cell–matrix signaling. Fibroblasts induce capillary-like differentiation of microvascular endothelial cell monolayers through cell–cell contact and soluble factors. It is then hypothesized that normal cellular precursors are recruited from the bone marrow to the site of a growing melanoma metastasis. Thus pathways for angiogenesis and vasculogenesis are guided through the cooperation of fibroblasts and melanoma cells perpetuated by the dominance of the metastatic melanoma cells. This revised version was published online in July 2006 with corrections to the Cover Date.     

Molecular clonality of in-transit melanoma metastasis

In-transit melanoma is characterized by an aggressive pattern of recurrence that is associated with a poorer prognosis. Because in-transit melanoma is considered to result from the intralymphatic trapping of melanoma cells between the primary tumor and regional lymph nodes, it provides an excellent model to assess genetic events associated with early metastasis. The hypothesis of this study was to determine whether in-transit metastases are clonal in origin and therefore, may have specific genetic alterations uniquely associated with this disease and the development of early metastasis. This was assessed using loss of heterozygosity (LOH) analysis for specific DNA microsatellite loci. Seventy-nine paraffin-embedded in-transit melanoma lesions from 25 patients (range, 2 to 9 lesions per patient; average, 3.4 lesions per patient) were assessed for LOH using eight microsatellite DNA markers on six chromosomes. In 19 of 25 patients (76%) LOH was demonstrated for at least one marker. The most frequent microsatellite marker demonstrating LOH was D9S157 (56%). Using LOH microsatellite markers to assess intertumor heterogeneity, six of 79 tumors (7.6%) demonstrated different profiles when compared to other lesions from the same patient. In-transit metastases from those patients demonstrating intertumor heterogeneity were further assessed using laser capture microdissection and DNA analysis, and revealed no significant intratumor heterogeneity. In conclusion, LOH was frequently observed in in-transit melanoma metastasis. Based on LOH analysis, in-transit metastases are clonal in origin. The establishment of clinically successful in-transit melanoma metastasis requires specific genetic events that seem to be unique and homogeneous for each patient.     

The expression of proteolytic enzymes at the dermal invading front of primary cutaneous melanoma predicts metastasis

The expression of three proteinases Cathepsin B (Cath. B), Cathepsin D (Cath. D) and Collagenase IV (Coll. IV) has been retrospectively analyzed within an immunohistochemical study on routinely fixed, paraffin embedded tissues from 147 primary cutaneous melanomas belonging to the classes pT3 and pT4. The development of these melanomas has been followed for at least five years. We compared the expression of these proteolytic enzymes in tumors that metastized during the follow-up-period with that in tumors that did not metastize. The expression at the dermal invading front of the tumors showed higher prognostic values (Cath. B chi 2 = 40.03, p < 0.001; Cath. D chi 2 = 90.95, p < 0.001; Coll. IV chi 2 = 44.46, p < 0.001) than the overall expression of these enzymes (Cath. B chi 2 = 5.63, p = 0.018; Cath. D chi 2 = 6.21, p = 0.010; Coll. IV chi 2 = 6.57, p = 0.010). The distribution of protease-expression inside the tumor turned out to be important for the prognostic value, which might also lead to higher prognostic confidence when applied to other tumors.     

Pregnancy promotes melanoma metastasis through enhanced lymphangiogenesis

The relationships of pregnancy and melanoma have been debatable. Our aim was to assess the influence of gestation on the course of melanoma in a classic murine model of tumor progression and in women. B16 mouse melanoma cells were injected in nonpregnant or pregnant mice on day 5 of gestation. Animals were evaluated for tumor progression, metastases, and survival. Tumor sections were analyzed for lymphatic and blood vessel number and relative surface and expression of angiogenic growth factors. Finally, primary melanomas from pregnant and nonpregnant women, matched for age and tumor thickness, were also considered. Tumor growth, metastasis, and mortality were increased in B16-injected pregnant mice. Tumors displayed an increase in intratumoral lymphangiogenesis during gestation. This increased lymphatic angiogenesis was not observed in normal skin during gestation, showing its specificity to the tumor. An analysis of melanoma from pregnant and matched nonpregnant women showed a similar increase in lymphatic vessels. Tumors from pregnant mice had increased expression of vascular endothelial growth factor A at the RNA and protein levels. The increased vascular endothelial growth factor A production by melanoma cells could be reproduced in culture using pregnant mouse serum. In conclusion, pregnancy results in increased lymphangiogenesis and subsequent metastasis. Caution should be applied in the management of patients with advanced-stage melanoma during gestation.     

Cytologic features of metastatic and recurrent melanoma in patients with primary cutaneous desmoplastic melanoma

Desmoplastic melanoma (DM) is a rare subtype of melanoma characterized by malignant spindle cells associated with prominent fibrocollagenous stroma. Primary melanomas may be entirely desmoplastic ("pure" DM) or exhibit a desmoplastic component admixed with a nondesmoplastic component ("combined" DM). The cytologic features of only 5 cases of DM have been reported previously. Fine-needle biopsy (FNB) specimens from 20 recurrent or metastatic lesions in patients with cutaneous DM and 20 recurrent or metastatic lesions from patients with primary cutaneous non-DM were examined and compared. FNB specimens of patients with DM were less cellular (P = .009) and less often exhibited intranuclear cytoplasmic invaginations (P = .008) and mitotic figures (P = .006) than specimens from patients with non-DM. "Combined" DMs were more commonly composed of epithelioid cells (P = .017) and less often contained bizarre/giant tumor cells (P = .010) than did "pure" DMs. Recurrent and metastatic DM has a range of cytologic appearances. Awareness of the cytologic features and careful clinicopathologic correlation will assist in accurate FNB diagnosis.     

Melanoma botryoides: a distinctive myxoid pattern of sino-nasal malignant melanoma

Two primary sino-nasal melanomas are presented which were characterized by their botryoid growth pattern and myxoid stroma. These polypoid tumours contained small amounts of melanin and only focal areas of epithelioid cells. An in situ component was present in both of the tumours. Malignant melanoma should be considered when confronted by a myxoid tumour (with or without melanin) in the sino-nasal region. These tumours are widely infiltrative, and there is no evidence to suggest that they will behave any differently from conventional, non-botryoid, non-myxoid sino-nasal melanomas.     

Melanoma of the lower female urogenital tract (gynecological melanoma)

Eight cases of melanoma of the lower female urogenital tract are presented. The lesions were located 5 in the vulva, 2 in the vagina and 1 in the urethra. Patients had a mean age of 58.3 (range 43-80). Most of vulvar melanomas were polypoid and black, 3 of them arose in the major labium, 2 in clitoris area; histologically, four tumors were superficial spreading melanomas and one unclassifiable. Grossly, one vaginal melanoma was nodular, one polypoid, both were black and arose in the lower vagina. Urethral melanoma arose in the distal part of the organ. Prognosis of gynecological melanoma is severe, as 5 out of 8 patients died in 5-52 months.     

A case of spitzoid melanoma with lymph node metastasis in a child

The distinction of a spitz nevus from a melanoma can be difficult and in some cases, impossible. A misdiagnosed spitz nevus can metastasize and lead to fatal outcomes, especially in children. A 5-yr-old girl presented with a 1-yr history of a solitary pinkish nodule on her left hand. On physical examination, she had a palpable left axillary lymph node. We performed biopsy and checked 3 sentinel lymph nodes (SLN) on her axillary area. The biopsy specimen showed multiple variably sized and shaped nests with large spindle or polygonal cells and SLN biopsy showed 3 of 3 lymph nodes that were metastasized. Under the diagnosis of spitzoid melanoma, she was treated with excision biopsy and complete left axillary lymph nodes were dissected. She received interferon-α2b subcutaneously at a dose of 8 MIU per day, 3 times weekly for 12 months, and shows no recurrence.     

Melanoma cell metastasis via P-selectin-mediated activation of acid sphingomyelinase in platelets

Metastatic dissemination of cancer cells is one of the hallmarks of malignancy and accounts for approximately 90 % of human cancer deaths. Within the blood vasculature, tumor cells may aggregate with platelets to form clots, adhere to and spread onto endothelial cells, and finally extravasate to form metastatic colonies. We have previously shown that sphingolipids play a central role in the interaction of tumor cells with platelets; this interaction is a prerequisite for hematogenous tumor metastasis in at least some tumor models. Here we show that the interaction between melanoma cells and platelets results in rapid and transient activation and secretion of acid sphingomyelinase (Asm) in WT but not in P-selectin-deficient platelets. Stimulation of P-selectin resulted in activation of p38 MAPK, and inhibition of p38 MAPK in platelets prevented the secretion of Asm after interaction with tumor cells. Intravenous injection of melanoma cells into WT mice resulted in multiple lung metastases, while in P-selectin-deficient mice pulmonary tumor metastasis and trapping of tumor cells in the lung was significantly reduced. Pre-incubation of tumor cells with recombinant ASM restored trapping of B16F10 melanoma cells in the lung in P-selectin-deficient mice. These findings indicate a novel pathway in tumor metastasis, i.e., tumor cell mediated activation of P-selectin in platelets, followed by activation and secretion of Asm and in turn release of ceramide and tumor metastasis. The data suggest that p38 MAPK acts downstream from P-selectin and is necessary for the secretion of Asm.     

Effect of anti-fibrinolytic therapy on experimental melanoma metastasis

Anti-fibrinolytic agents such as aprotinin and ε-aminocaproic acid (EACA) are used clinically to decrease peri-operative bleeding. Use of these treatments during cancer-related surgeries has led to investigation of the effect of fibrinolysis inhibition on cancer cell spread. The ability of aprotinin to reduce proteolytic activity of proteases required for metastasis suggests that it could have an anti-metastatic effect in patients undergoing tumor resection. However, many metastatic cells in the vasculature of a secondary tissue are associated with a micro-thrombus. The association of tumor cells with thrombi has been shown to increase their survival; therefore inhibition of plasmin-mediated fibrinolysis might instead increase metastatic cell survival by enhancing the association between thrombi and tumor cells. The goal of this work was to determine the effect of anti-fibrinolytic treatment on experimental metastasis and to establish the role of coagulation factors in this effect. The metastatic ability of B16F10 melanoma cells was evaluated in vivo following cell or animal pre-treatment with aprotinin or EACA. Additionally, a novel in vivo technique was developed, to permit analysis of tumor cell association with thrombi in the lung microvasculature using confocal microscopy. Aprotinin and EACA treatment of mice resulted in a significant increase in lung metastasis. Aprotinin treatment increased the size of thrombi in association with cells arrested in lung capillaries. This study suggests that clinical use of anti-fibrinolytic agents for cancer-related surgeries could result in increased metastatic ability of those cells shed immediately prior to and during surgery, and that this approach thus requires further study.