Yasuhiko Tamada

Identification of programmed cell death in normal human skin tissues by using specific labelling of fragmented DNA

Programmed cell death (PCD) in normal human skin tissues was studied by using in situ specific labelling of fragmented DNA. This labelling method clearly stained the nuclei of Henles layer in the bulb of the anagen hair follicle in serial sections, and the nuclei of the inner root sheath cuticle cells and Huxleys layer cells showed positive staining in the upper part of the hair follicles. This staining pattern was consistent with the sequence of keratinization in the three layers. The nuclei of differentiated cells located at the centre of the sebaceous glands, and those of the granular keratinocyte layer, were also stained. These findings suggest that PCD might play a key role in the terminal differentiation of the epidermis and epidermal appendages.

Successful treatment of toenail onychomycosis with photodynamic therapy.

Although recent progresses in oral antifungal agents have made it possible to treat onychomycosis effectively, these drugs can have considerable adverse liver or kidney effects and medication interactions in special populations such as children, the elderly, and patients with underlying systemic diseases. We describe 2 patients with toenail onychomycosis who were sucessfully treated with photodynamic therapy (PDT).

Imatinib mesylate inhibits the growth of metastatic lung lesions in a patient with dermatofibrosarcoma protuberans

derived from the neural crest, whereas Langerhans cells are derived from bone marrow. Merkel cells are considered to originate from the neural crest and to form specialized nerve endings. Thus, it is of interest that the p63-negative cells did not originate from epidermal germinative cells. In contrast, skin appendages are derived from epidermal germinative cells in the embryonic stage. The observation that p63 expression was limited to myoepithelial cells both in the eccrine and apocrine glands supports the hypothesis that myoepithelial cells of the sweat glands originate not from mesenchymal cells but from primary epithelial germinative cells. The fact that p63 expression was limited to the outer root sheath cells and hair matrix cells suggests that cells of the inner root sheath would be more differentiated than those of the outer root sheath and hair matrix. Similarly, in terms of p63 expression, vacuolated cells in sebaceous glands and secretory cells of sweat glands are definitively more differentiated than germinative cells. Our results support the concept that p63 is critical for maintaining the germinative cells necessary to sustain epithelial development and morphogenesis. From this exploration of the localization of p63 protein in normal human skin, we postulate that p63 protein may be essential for regulating the differentiation of cells in normal human skin.

Pitted keratolysis: clinical manifestations in 53 cases

Pitted keratolysis (PK) has been reported to be more common among bare‐footed people living in tropical regions. It is now known that the disease is not limited to the tropics but has a world‐wide distribution. However, no study has previously been performed analysing the clinical manifestations of the disease in temperate countries. A survey of 53 patients revealed several distinctive clinical features. Hyperhidrosis is the most frequently observed symptom of this condition. Malodour and sliminess of the skin are also distinctive features, evident in 88.7% and 69.8% of the cases, respectively. The most common sites of onset of PK are the pressure‐bearing areas, such as the ventral aspect of the toe, the ball of the foot and the heel. The next most common site is a friction area, the interface of the toes. Lesions are rarely seen on the non‐pressure‐bearing locations. Some of the primary lesions originate as a small defect along the plantar furrow, which gradually grows into the characteristic crateriform pit. Several clinical features are helpful in diagnosing PK.

Lichen planus pemphigoides: Identification of 180 kd hemidesmosome antigen

We describe a man with lichen planus pemphigoides. Direct immunofluorescence studies of peribullous skin showed linear deposition of IgG and C3 in the basement membrane zone. Indirect immunofluorescence studies disclosed circulating anti-basement membrane zone antibodies. Immunoelectron microscopy demonstrated binding of antibodies to the hemidesmosomes and lamina lucida. The patients serum defined only the minor bullous pemphigoid antigen with a molecular weight of 180 kd. These findings suggest the coexistence of lichen planus and bullous pemphigoid in lichen planus pemphigoides.

Histological changes and involvement of apoptosis after photodynamic therapy for actinic keratoses

Background  Photodynamic therapy (PDT), which employs a combination of a tumour‐localizing photosensitizer and visible light, has been used to treat superficial malignancies in the epidermis.

Oncolytic virotherapy for malignant melanoma with herpes simplex virus type 1 mutant HF10.

BACKGROUND Many viruses have been engineered and evaluated for their potential as therapeutic agents in the treatment of malignant neoplasm, including malignant melanoma. OBJECTIVE In this study, we investigated the efficacy of HF10, an attenuated, replication-competent HSV, in immunocompetent animal models with malignant melanoma. METHODS For in vitro study, viral cytotoxicity assays and replication assays were performed both in human and mouse melanoma cells. For the study in vivo, intraperitoneally disseminated or subcutaneous melanoma models were prepared in DBA/2 mice using clone M3 cells, then HF10 was inoculated intraperitoneally or intratumorally. Therapeutic efficacy of HF10 was assessed by survival, tumor growth, and histopathological analysis. RESULTS HF10 infection produced cytolytic effects in melanoma cells at various multiplicities of infection (MOI). In the intraperitoneal melanoma model, all mice survived when given intraperitoneal injections of HF10 compared with 100% fatality in the control mice. In the subcutaneous tumor model, intratumoral inoculation of HF10 significantly reduced tumor growth. Histology and immunohistochemistry showed tumor lysis and inflammatory cell infiltration after intratumoral HF10 inoculation. Viral antigen was retained at the inoculation site until 7 days post-infection. HF10-treated intraperitoneal tumor mice were also protected against tumor rechallenge. HF10 also affected the non-inoculated contralateral tumor when injected into the ipsilateral tumor of mice, suggesting that HF10 can induce systemic antitumor immune responses in mice. CONCLUSION Oncolytic viral therapy using HF10 was effective in melanoma mouse models, and intratumoral injection of HF10 induced systemic antitumor responses. These results suggest that HF10 is a promising agent for the treatment of advanced melanoma.

5-Aminolevulinic acid-based photodynamic therapy for the treatment of two patients with extramammary Paget's disease.

Photodynamic therapy (PDT), which employs a combination of a tumor‐localizing photosensitizer and visible light, has been used in the treatment of extramammary Pagets disease (EMPD). Two patients with EMPD were treated with PDT using 5‐aminolevulinic acid (ALA). Histologically, in both cases, Pagets cells were present within the epidermis. Case 1 was a 92‐year‐old male who underwent total extirpation for treatment of EMPD. Two topical ALA‐PDT treatments were applied to parts of the lesions at a total dose of 200 J/cm2. Case 2 was a 73‐year‐old female, whose lesions in the right labia majora were treated with 3 topical ALA‐PDT sessions at a total dose of 300 J/cm2. Clinical findings after the irradiation showed improvement in both patients, and elimination of tumor cells in the epidermis was confirmed histologically. Case 1 had no recurrence in the irradiation field at three months after PDT. Case 2 had a recurrence only in the periphery parts of the lesions at two months after PDT, but the periphery lesions remitted with two more PDT treatments. Topical ALA‐PDT is an effective treatment for EMPD with tumor cells within the epidermis. It is noninvasive and achieves a cosmetically excellent outcome, especially in elderly patients and those in poor general condition.

Photodynamic therapy for the treatment of actinic cheilitis

Although actinic cheilitis is a common disease, it should be treated carefully because it can undergo malignant transformation. We report a case of actinic cheilitis treated with photodynamic therapy (PDT) using 5‐aminolevulinic acid (ALA), with satisfactory outcome in both clinical and pathological aspects. Actinic cheilitis is a pathologic condition affecting mainly the lower lip caused by long‐term exposure of the lips to the UV radiation in sunlight. Analogous to actinic keratosis of the skin, actinic cheilitis is considered as a precancerous lesion and it may develop into squamous cell carcinoma. We report a case of actinic cheilitis treated with PDT using ALA, with satisfactory outcome in both clinical and pathological aspects.

Primary cutaneous T‐cell lymphoma of unspecified type with cytotoxic phenotype: Clinicopathological analysis of 27 patients

The objective of our study was to investigate the clinicopathological features of the currently ill‐defined subtype of primary cutaneous T‐cell lymphoma of unspecified type (CTCLU) with a cytotoxic phenotype and no Epstein–Barr virus (EBV) association. A series of 27 patients with CTCLU (median age 49 years; range 25–87 years; 18 men) was reviewed. Performance status scores above 1 (7%), clinical stages above 2 (15%), B symptoms (26%), extracutaneous involvement (30%), and a fatal course within 1 year of diagnosis (19%) were observed infrequently. The International Prognostic Index was high or high to intermediate in 11%, and the Prognostic Index for Peripheral T‐cell Lymphoma unspecified was above group 2 in 22%. Notably, the rates of spontaneous regression and T‐cell receptor gene rearrangements by polymerase chain reaction analysis were seen in 26 and 17% of our cases, respectively. Histologically, 22 patients had subcutaneous involvement of whom eight showed a lethal clinical course, and five patients without subcutaneous involvement were all survivors. Immunophenotypical and morphological features allowed us to subclassify our cases according to the following four categories: (1) epidermotropic CD8+ T‐cell lymphoma (n = 5); (2) cutaneous γ/δ T‐cell lymphoma (n = 8); (3) cutaneous α/β pleomorphic T‐cell lymphoma (n = 8); and (4) cutaneous medium/large pleomorphic T‐cell lymphoma, not otherwise specified (n = 6). All four of these groups of lymphomas exhibited a relatively favorable clinical course compared to previous reports. However, epidermotropic CD8+ T‐cell lymphoma appeared to be unique with a higher ratio (80%) of spontaneous regression, a lower ratio (40%) of subcutaneous involvement, and a more favorable clinical course than the other three subcategories. (Cancer Sci 2009; 100: 33–41)