Papillon-Lefèvre syndrome and malignant melanoma. A high incidence of melanoma development in Japanese palmoplantar keratoderma patients.

Papillon-Lefèvre syndrome (PLS) is a rare autosomal-recessive genodermatosis characterized by palmoplantar hyperkeratosis and severe early-onset periodontitis. The development of malignant cutaneous neoplasms within the hyperkeratotic lesions of the syndrome is quite rare. Here, we report on a 51-year-old Japanese woman with PLS associated with recurrent malignant melanoma (MM). Mutation analysis of the cathepsin C gene revealed that the proband was homozygous for a missense mutation, c.415G-->A, which is predicted to result in the amino acid substitution p.G139R. Including our case, 4 families have been described as having PLS with MM, 3 of which are Japanese, implying a high incidence of melanoma development in Japanese PLS patients. We suggest that hereditary palmoplantar keratoderma (PPK) in Japanese patients might be predisposed to MM. A literature review revealed that in 18 cases of MM-associated PPK, 13 (76%) were Japanese, suggesting a high incidence of MM in Japanese PPK patients. This tendency might be attributable to the high frequency of acral lentiginous melanoma in Japanese subjects, in contrast to a lower frequency of this subtype in Caucasians.

Significance of sentinel node biopsy in the management of squamous cell carcinoma arising from recessive dystrophic epidermolysis bullosa.

The most life-threatening complication developing in patients with recessive dystrophic epidermolysis bullosa (RDEB) is squamous cell carcinoma (SCC). To improve patient prognosis, early detection of regional lymph node metastasis is required. Herein, we report a patient diagnosed with non-Hallopeau-Siemens RDEB who developed SCC on the left foot with inguinal lymph node swelling. Use of the sentinel node biopsy (SNB) technique favorably minimized defective damage to the inguinal region in this case. Genetic analysis identified one novel COL7A1 mutation, a maternal c.238G > C (p.A80P) and one previously reported mutation, a paternal c.3631C > T (p.Q1211X). A published work review demonstrated that no COL7A1 mutations specific for SCC development in RDEB have previously been identified. It remains unclear if SNB in combination with gene diagnosis is beneficial for the management of SCC in RDEB patients, however, because of the limited number of case reports. To address this issue, COL7A1 mutational analysis should be performed in as many cases of RDEB as possible.

A case of bullous dermatitis artefacta possibly induced by a deodorant spray.

Dermatitis artefacta is one of a spectrum of factitious diseases etiologically responsible for skin lesions denied by patients. These factors often make it difficult to identify the causative agents of the condition. Herein, we report a case of bullous dermatitis artefacta in a 12-year-old girl, for which a deodorant spray was suspected as the probable cause. Pathological examination revealed subepidermal blistering with full-thickness necrosis of the epidermis, suggesting a thermo- or cryo-induced injury. Psychological testing demonstrated her immaturity and dependence. In searching for the causative agent, we suspected a deodorant spray as a blister-inducing agent. We succeeded in reproducing a similar blister lesion on the volunteer's healthy skin using the same spray. Psychiatric involvement significantly complicates the treatment of factitious diseases, including dermatitis artefacta. Cooperation among dermatologists, psychiatrists and the patient's family members is required for ensuring a favorable prognosis.

Human metallothionein gene expression is upregulated by beta-thujaplicin: possible involvement of protein kinase C and reactive oxygen species.

Recently, we discovered that beta-thujaplicin (BT) induces metallothionein (MT) expression in mouse keratinocytes, both in vivo and in vitro. However, the molecular mechanisms by which BT exerts its biological effects have not been elucidated. The purpose of this study is to explore the signal transduction pathway involved in the MT mRNA induction by BT. Using a HaCaT keratinocyte cell line, Northern blotting was performed for analyzing the human MT-IIA mRNA expression levels in combination with BT and a number of protein kinase (PK) inhibitors including H7, HA1004 and a PKC-specific inhibitor chelerythrin. CAT assays with the MT-IIA gene promorter-CAT construct were conducted for examining the transcriptional regulation by BT of MT. A free radical scavenger N-acetylcysteine (NAC) was used for analyzing a role of oxidative stress for the MT gene induction by BT. BT increased MT-IIA gene transcript levels and CAT activity in a dose-dependent fashion in HaCaT cells. The increase in MT-IIA mRNA levels and CAT activity were completely suppressed by H7 but not by HA1004. In addition, chelerythrin prevented BT-inducible MT-IIA promoter activation. Furthermore, NAC suppressed BT-inducible MT-IIA promoter activation. These results demonstrate that BT is a potent activator of the MT-IIA gene promoter and that PKC activation and reactive oxygen species are implicated in BT-inducible MT-IIA gene expression. BT may be a useful tool for dissecting the signal transduction pathway mediating MT-IIA promoter activation.