A case report of cutaneous polyarteritis nodosa in siblings.

Cutaneous polyarteritis nodosa (CPAN) is characterized by a necrotizing vasculitis of small and medium-sized arteries in the skin, which can be associated with fever, arthralgia, myalgia, and neuropathy, but, unlike polyarteritis nodosa (PAN), there is no visceral involvement. CPAN is rare in childhood. We report two siblings who developed CPAN during childhood. Interestingly, both had Mediterranean fever gene (MEFV) mutation, i.e. heterozygous E148Q. They also shared HLA-A24, -DR15 alleles. Simultaneous occurrence of MEFV mutation and HLA alleles with CPAN has never been reported in Japan. These cases could provide some hereditary clue for the development of CPAN.

Clinical and epidemiological analysis in 149 cases of rhododendrol-induced leukoderma.

Rhododendrol-induced leukoderma is an acquired depigmentation that develops mainly at the contact site after repeated use of skin-whitening cosmetics containing rhododendrol. In most cases, cessation of further depigmentation or occurrence of repigmentation is observed after discontinuing the use of cosmetics. However, some patients develop vitiligo vulgaris through the spread of depigmentation into the non-exposed areas. Our study aims to investigate the patient-specific factors that may affect the extent of depigmentation or repigmentation, as well as development of vitiligo vulgaris. The degree of depigmentation of the face, neck and hands where exposed to rhododendrol was scored using photographs over time. The relationships between depigmentation score at first visit/improvement rate of depigmentation score and patient demographics were evaluated and three important clinical observations were made. First, repigmentation of the face was superior compared with that of the hands and neck, suggesting a possible role for the migration and differentiation of melanocyte stem cells from hair follicles, as a mechanism of repigmentation. Second, the intensity of rhododendrol exposure did not contribute to differences in the severity of depigmentation. This suggested a possibility of underlying genetic susceptibility to melanocyte cytotoxicity or immune reaction. Third, depigmentation score at first visit and past history of atopic dermatitis were significantly high in patients who developed vitiligo vulgaris. This suggested that severe chemical damage of melanocytes by rhododendrol leads to a higher risk of developing vitiligo vulgaris through the possible involvement of an immune reaction. These clinical observations may help to further understand the pathogenesis of rhododendrol-induced leukoderma.

Circulating melanoma cells as a potential biomarker to detect metastasis and evaluate prognosis.

TNM staging is mainly used to evaluate the prognosis of melanoma patients. Serum biomarkers such as 5-S-cysteinyldopa (5-S-CD) have occasionally been used but most do not respond until the tumour burden becomes high. Recently, circulating melanoma cells (CMC) have been reported as a possible new biomarker to detect metastasis, monitor treatment response and predict prognosis. The object of this exploratory study was to evaluate the efficacy of CMC to detect metastasis and predict prognosis by cross-sectional and prospective observational analyses, respectively. Altogether 15 patients with stages II-IV melanoma were enrolled and CMC were enumerated by CellSearch system with cut-off values of two cells/7.5 mL. Serum 5-S-CD and lactate dehydrogenase (LDH) were also measured. The sensitivity of CMC and 5-S-CD for the detection of metastasis was 33 and 50%, respectively. The combination of CMC and 5-S-CD showed a sensitivity of 67%, the best performance among CMC, 5-S-CD, LDH and any combination of two of the markers. Additionally, a 30-month prospective observation showed that CMC could segregate patients with poorer prognosis. The median survival time for the patients with <2 CMC and those with ≥2 CMC was 19.5 and 4.5 months, respectively. The limitation of this study is the small sample size. These preliminary results indicate CMC may complement the efficacy of 5-S-CD to detect metastasis and can be a prognostic marker. Although there is still room for improvement to maximise the sensitivity, the CellSearch system is reproducible, standardised and suitable for multi-centre studies.

Diagnosis of eight groups of xeroderma pigmentosum by genetic complementation using recombinant adenovirus vectors.

Because patients with xeroderma pigmentosum (XP) must avoid ultraviolet (UV) light from an early age, an early diagnosis of this disorder is essential. XP is composed of seven genetic complementation groups, XP-A to -G, and a variant type (XP-V). To establish an easy and accurate diagnosis of the eight disease groups, we constructed recombinant adenoviruses that expressed one of the XP cDNA. When fibroblasts derived from patients with XP-A, -B, -C, -D, -F or -G were infected with the adenovirus expressing XPA, XPB, XPC, XPD, XPF or XPG, respectively, and UV-C at 5-20 J/m2 was irradiated, cell viability was clearly recovered by the corresponding recombinant adenoviruses. In contrast, XP-E and XP-V cells were not significantly sensitive to UV irradiation and were barely complemented by the matched recombinant adenoviruses. However, co-infection of Ad-XPA with Ad-XPE increased survival rate of XP-E cells after UV-C exposure. When XP-V cell strains, including one derived from a Japanese patient, were infected with Ad-XPV, exposed to UV-B and cultured with 1 mmol/L of caffeine, flow cytometry detected a characteristic decrease in the S phase in all the XP-V cell strains. From these results, the eight groups of XP could be differentiated by utilizing a set of recombinant adenoviruses, indicating that our procedure provides a convenient and correct diagnostic method for all the XP groups including XP-E and XP-V.

Effects of rhododendrol and its metabolic products on melanocytic cell growth.

BACKGROUND: Rhododendrol (RD), a skin-whitening agent, is believed to be associated with cases of cosmetics-related leukoderma that have been reported in Japan. Recently, we have shown that RD is catalyzed by tyrosinase to produce putative toxic metabolites RD-catechol and RD-cyclic catechol. OBJECTIVE: To examine the cytotoxicity and production of reactive oxygen species (ROS) in melanocytic cells by RD and its metabolic products. METHODS: The growth inhibitory effect of RD or its metabolite on the normal human epidermal melanocyte (NHEM) and B16F1 cells was assessed by cell counting or WST assay. ROS production was detected by flow cytometry and confocal microscopy after cells were treated with 2',7'-dichlorofluorescein and RD or its metabolite. RESULTS: Growth of NHEM derived from African American (NHEMb) and B16F1 cells was suppressed by 300µM or more RD. Growth inhibitory activity of RD (IC50 of B16F1: 671µM) was weaker than hydroquinone (IC50 of B16F1: 28.3µM) or resveratrol (IC50 of B16F1: 27.1µM). Flow cytometric analysis detected ROS production in the NHEMb and B16F1 cells exposed to RD. However, neither RD nor H2O2 increased the subG1 fraction of these melanocytic cells. RD-catechol and RD-cyclic catechol inhibited growth of NHEMb and B16F1 cells much more strongly than did RD. RD-catechol, as well as RD, produced ROS detected by both flow cytometry and immunostaining, while RD-cyclic catechol produced a hardly detectable amount of ROS in B16F1 cells. CONCLUSIONS: These results suggest that RD exerts the cytotoxicity in melanocytic cells through its oxidative metabolites and that ROS plays a role in RD-mediated cytotoxicity.

Melanoma-Targeted Chemothermotherapy and In Situ Peptide Immunotherapy through HSP Production by Using Melanogenesis Substrate, NPrCAP, and Magnetite Nanoparticles.

Exploitation of biological properties unique to cancer cells may provide a novel approach to overcome difficult challenges to the treatment of advanced melanoma. In order to develop melanoma-targeted chemothermoimmunotherapy, a melanogenesis substrate, N-propionyl-4-S-cysteaminylphenol (NPrCAP), sulfur-amine analogue of tyrosine, was conjugated with magnetite nanoparticles. NPrCAP was exploited from melanogenesis substrates, which are expected to be selectively incorporated into melanoma cells and produce highly reactive free radicals through reacting with tyrosinase, resulting in chemotherapeutic and immunotherapeutic effects by oxidative stress and apoptotic cell death. Magnetite nanoparticles were conjugated with NPrCAP to introduce thermotherapeutic and immunotherapeutic effects through nonapoptotic cell death and generation of heat shock protein (HSP) upon exposure to alternating magnetic field (AMF). During these therapeutic processes, NPrCAP was also expected to provide melanoma-targeted drug delivery system.

Mechanism of putative neo-antigen formation from N-propionyl-4-S-cysteaminylphenol, a tyrosinase substrate, in melanoma models.

Metastatic melanoma is resistant to conventional therapies. N-propionyl-4-S-cysteaminylphenol (NPrCAP), an N-protected sulfur-amine analog of tyrosine, is a good substrate for tyrosinase and is selectively incorporated into melanoma cells, causing cytotoxicity in vitro and in vivo. We have recently shown that intratumoral injections of NPrCAP suppress not only the growth of primary B16F1 melanoma tumors but also of secondary, re-challenged tumors. The participation of CD8(+) T cells has been suggested for the NPrCAP-mediated anti-B16 melanoma immunity. In this study, the molecular mechanism of the NPrCAP cytotoxicity and immunogenicity was examined. The phenol NPrCAP was shown to be activated by mushroom tyrosinase to the ortho-quinone N-propionyl-4-S-cysteaminyl-1,2-benzoquinone (NPrCAQ), and the structure was confirmed by reducing it to the corresponding catechol. NPrCAQ reacted rapidly with biologically relevant sulfhydryl compounds such as cysteine, glutathione and bovine serum albumin. The NPrCAQ-thiol adduct formation was proven with a model thiol N-acetylcysteine by spectroscopic methods. The production and release of NPrCAQ-protein adducts was verified in B16F1 melanoma cells in vitro and in B16F1 melanoma-bearing mice in vivo through the detection of 5-S-cysteaminyl-3-S-cysteinylcatechol after acid hydrolysis of the protein fraction. These results suggest that the phenol NPrCAP, acting as a prohapten, can be activated in melanoma cells by tyrosinase to the quinone-hapten NPrCAQ, which binds to melanosomal proteins through their cysteine residues to form possible neo-antigens, thus triggering the immunological response. NPrCAP thus represents a potential new approach to immunotherapy against metastatic melanoma.

N-propionyl-4-S-cysteaminylphenol induces apoptosis in B16F1 cells and mediates tumor-specific T-cell immune responses in a mouse melanoma model.

BACKGROUND: N-propionyl-4-S-cysteaminylphenol (NPr-4-S-CAP) is selectively incorporated into melanoma cells and degrades them. However, it remains unclear whether NPr-4-S-CAP can induce cell death associated with the induction of host immune responses and tumor suppression in vivo. OBJECTIVE: To examine the molecular mechanism of NPr-4-S-CAP-mediated cytotoxicity toward melanoma cells and to test whether NPr-4-S-CAP can suppress transplanted primary and secondary B16F1 melanomas. METHODS: Cytotoxicity and apoptosis of melanoma cells were assessed by cell counting, flow cytometry, and detection of reactive oxygen species (ROS) and apoptotic molecules. NPr-4-S-CAP-associated host immunity was studied using a B16F1 mouse melanoma model through the application of CD4- and CD8-specific antibodies and tetramer assay. RESULTS: NPr-4-S-CAP suppressed growth of pigmented melanoma cells associated with an increase of intracellular ROS, activation of caspase 3 and DNA fragmentation, suggesting that NPr-4-S-CAP mediated ROS production, eliciting apoptosis of melanoma cells. Growth of transplanted B16F1 melanomas was inhibited after the consecutive intratumoral injections of NPr-4-S-CAP, and the tumor growth after rechallenge of B16F1 was significantly suppressed in the treated mice. This suppression occurred when the treated mice were given the anti-CD4 antibody, but not the anti-CD8 antibody. Tetramer assay demonstrated increased TYRP-2-specific CD8(+) T cells in the lymph node and spleen cells prepared from NPr-4-S-CAP-treated B16F1-bearing mice. CONCLUSIONS: These suggest that NPr-4-S-CAP induces apoptosis in melanoma cells through ROS production and generates CD8(+) cell immunity resulting in the suppression of rechallenged B16F1 melanoma.

Melanoma-targeted chemo-thermo-immuno (CTI)-therapy using N-propionyl-4-S-cysteaminylphenol-magnetite nanoparticles elicits CTL response via heat shock protein-peptide complex release.

Melanogenesis substrate, N-propionyl-4-S-cysteaminylphenol (NPrCAP) is specifically taken up by melanoma cells and inhibits their growth by producing cytotxic free radicals. By taking advantage of this unique chemical agent, we have established melanoma-targeting intracellular hyperthermia by conjugating NPrCAP with magnetite nanoparticles (NPrCAP/M) upon exposure to an alternating magnetic field (AMF). This treatment causes cytotoxic reaction as well as heat shock responses, leading to elicitation of antitumor immune response, which was proved by tumor rechallenge test and CTL induction. We found the level of heat shock protein 72 (Hsp72) to be increased in the cell lysate and culture supernatant after intracellular hyperthermia. Melanoma-specific CD8(+) T-cell response to dendritic cells loaded with hyperthermia-treated tumor lysate was enhanced when compared with non-treated tumor lysate. When heat shock protein, particularly Hsp72, was immuno-depleted from hyperthermia-treated tumor cell lysate, specific CD8(+) T-cell response was abolished. Thus, it is suggested that antitumor immune response induced by hyperthermia using NPrCAP/M is derived from the release of HSP-peptide complex from degraded tumor cells. Therefore, this chemo-thermo-immuno (CTI)-therapy might be effective not only for primary melanoma but also for distant metastasis because of induction of systemic antimelanoma immune responses.

N-propionyl-cysteaminylphenol-magnetite conjugate (NPrCAP/M) is a nanoparticle for the targeted growth suppression of melanoma cells.

A magnetite nanoparticle, NPrCAP/M, was produced for intracellular hyperthermia treatment of melanoma by conjugating N-propionyl-cysteaminylphenol (NPrCAP) with magnetite and used for the study of selective targeting and degradation of melanoma cells. NPrCAP/M, like NPrCAP, was integrated as a substrate in the oxidative reaction by mushroom tyrosinase. Melanoma, but not non-melanoma, cells incorporated larger amounts of iron than magnetite from NPrCAP/M. When mice bearing a B16F1 melanoma and a lymphoma on opposite flanks were given NPrCAP/M, iron was observed only in B16F1 melanoma cells and iron particles (NPrCAP/M) were identified within late-stage melanosomes by electron microscopy. When cells were treated with NPrCAP/M or magnetite and heated to 43 degrees C by an external alternating magnetic field (AMF), melanoma cells were degraded 1.7- to 5.4-fold more significantly by NPrCAP/M than by magnetite. Growth of transplanted B16 melanoma was suppressed effectively by NPrCAP/M-mediated hyperthermia, suggesting a clinical application of NPrCAP/M to lesional therapy for melanoma. Finally, melanoma cells treated with NPrCAP/M plus AMF showed little sub-G1 fraction and no caspase 3 activation, suggesting that the NPrCAP/M-mediated hyperthermia induced non-apoptotic cell death. These results suggest that NPrCAP/M may be useful in targeted therapy for melanoma by inducing non-apoptotic cell death after appropriate heating by the AMF.