Novel MEN1 gene mutations in familial multiple endocrine neoplasia type 1

The recent isolation of the gene responsible for multiple endocrine neoplasia type 1 (MEN 1) has enabled direct genetic diagnosis for people with endocrine tumors and family members of affected patients. Although MEN 1 is rarely recognized in the Japanese population compared to its prevalence in Caucasians, we have previously reported a high prevalence of this disease in a limited area (Nagano Prefecture; population, 2.15 million). In this communication, we report mutations of the MEN1 gene in kindreds living in Nagano Prefecture. The absence of a common mutation among these kindreds indicates that the high prevalence of MEN 1 in this area is not due to a regional accumulation of patients descended from a common ancestor. This result implies that the prevalence of MEN 1 in other areas of Japan could also be higher than had been thought.

MDM2 protein overexpression inhibits apoptosis of TF-1 granulocyte-macrophage colony-stimulating factor-dependent acute myeloblastic leukemia cells

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a growth factor for acute myeloblastic leukemia (AML) cells. Murine double minute 2 (MDM2) oncoprotein, a potent inhibitor of wild-type p53 (wtp53), can function both to induce cell proliferation and enhance cell survival, and is frequently overexpressed in leukemias. Therefore, we focused on the importance of MDM2 protein in GM-CSF-dependent versus GM-CSF- independent growth of AML cells. The TF-1 AML cell line, which has both wtp53 and mutant p53 genes, showed GM-CSF-dependent growth; deprivation of GM-CSF resulted in G1 growth arrest and apoptosis. MDM2 mRNA and protein were highly expressed in proliferating TF-1 cells in the presence of GM-CSF and decreased significantly with deprivation of GM-CSF. In contrast, p53 protein increased with GM-CSF deprivation. Ectopic overexpression of MDM2 in TF-1 AML cells conferred resistance to GM-CSF deprivation, and is associated with decreased p53 protein expression. Moreover, a variant of TF-1 cells that grows in a GM-CSF-independent fashion also expressed high levels of MDM2 and low levels of p53. These results suggest that GM-CSF-independent growth of AML cells is associated with overexpression of MDM2 protein and related modulation of p53 expression.

Recurrent pemphigus vulgaris limited to the surgical area after mastectomy

A 45-year-old Japanese female presented with bullae and erosions on the trunk in December 1987. The histologic findings revealed a suprabasal cleft and acantholytic cells. Immunofluorescence staining showed IgG autoantibodies in the intercellular spaces. With a working diagnosis of pemphigus vulgaris, she was treated successfully with low dosage prednisolone. Adenocarcinoma of the right breast was found in March 1994, and she received a mastectomy followed by breast reconstruction that used a transverse rectus abdominis muscle flap. Six months later, vesicobullous eruptions developed and were limited to the surgical area (right chest and abdomen). The histopathologic and direct immunofluorescence findings were consistent with pemphigus vulgaris. Although these skin lesions improved with high dosages of prednisolone, she died of multiple metastases due to the breast cancer.

Mutational analysis of the RET proto-oncogene in 71 Japanese patients with medullary thyroid carcinoma

Multiple endocrine neoplasia types 2A and 2B (MEN2A and MEN2B) and familial medullary thyroid carcinomas (FMTC) are caused by germline mutations in the RET proto-oncogene. To investigate the spectrum of RET mutations among Japanese patients, we screened the RET gene in 71 patients with thyroid carcinomas. The panel included representatives of 44 families carrying FMTC or MEN2, 22 sporadic medullary thyroid carcinomas (MTCs), and five MTCs without familial information. Mutations in nucleotide sequences encoding one of three specific cysteine residues in the extracellular domain of the RET protein were found in 33 of the 34 MEN2A patients and in five of the six FMTC patients examined. A mutation at codon 918, causing the substitution of threonine for methionine in the tyrosine kinase domain of the protein, was found in germline DNAs of all four patients with MEN2B and in two of the 22 patients with sporadic MTCs; codon 918 was mutated somatically in tumor DNAs from three other sporadic cases. Germline mutations of codon 768, GAG to GAC (Glu to Asp), were detected in one FMTC, in one patient with sporadic MTC, and in one of the patients without familial information. Two somatic mutations, an Asp to Gly substitution at codon 631 and a Cys to Arg substitution at codon 634, had not been reported previously. Of five germline mutations found among the 22 sporadic cases, four were confirmed as de novo mutations since in each case neither parent carried the mutation. As nearly one-fourth of the patients with sporadic MTCs carried germline mutations and 50% of their children are expected to develop MTC and other endocrine tumors, these results indicated the importance of careful clinical surveillance of family members of any patient with MTC.

Bullous systemic lupus erythematosus: detection of antibodies against noncollagenous domain of type VII collagen

A 9-year-old girl with systemic lupus erythematosus developed bullous eruption. Histopathologic examination showed subepidermal blistering and immunoglobulins (IgG, IgM, IgA) and complement components (C1q, C3) deposited linearly at the basement membrane zone. IgG in this patient's serum bound to the dermal side of 1 mol/L sodium chloride-split normal human skin, and a 290 kd protein was identified in the dermal extract. The patient's serum recognized various epitopes on the noncollagenous domain as demonstrated by the use of fusion proteins of type VII collagen. Resolution of the bullous eruption occurred after treatment with dapsone.

Membranous and soluble forms of Fas antigen in cutaneous lupus erythematosus

The role of Fas-mediated apoptosis in cutaneous lupus erythematosus (LE) is still unclear, although the Fas/FasL system has been investigated in autoimmune diseases in relation to impaired apoptosis. In order to elucidate the connections between acute cutaneous LE (ACLE) and chronic cutaneous LE (CCLE), we determined the expression of membranous Fas antigen (mFas) on peripheral blood mononuclear cells (PBMC) by flow cytometry and the levels of the soluble form of the Fas antigen (sFas) in sera. The ratio and the mean fluorescence intensity of mFas were much higher in ACLE patients than in others, including patients with CCLE and atopic dermatitis and normal healthy controls. The levels of sFas in ACLE and CCLE patients were also elevated, and there was a significant increase in sFas levels in ACLE patients over that in CCLE patients. Immunohistochemical studies revealed that Fas antigen was predominantly expressed on infiltrating cells around blood vessels and appendages in ACLE and CCLE patients. Based on these findings, it is suggested that the expression of Fas antigen is closely associated with the activation of circulating lymphocytes, especially in ACLE patients, but is not directly associated with keratinocyte damage.

Complete genomic structure DNA polymorphisms, and alternative splicing of the human AF-6 gene

In our previous work, detailed deletion mapping of ovarian cancers indicated that a 300-kb region of chromosome 6q27 was likely to contain one or more putative tumor suppressor genes associated with development of this type of cancer. DNA sequencing in the region disclosed the presence of AF-6, a gene that had been identified as the ALL-1 fusion partner involved in acute myeloid leukemias with t(6;11)(q27;q23) translocations. In the work reported here, we determined the complete genomic sequence of the AF-6 gene, including exon-intron boundaries, and found six DNA polymorphisms. One of them, an insertion/deletion polymorphism, determined the presence or absence of seven amino acids in the AF-6 product. We also identified two alternatively spliced forms of the gene; the two novel transcripts would encode additional C-terminal peptides in comparison to the reported protein. Sequencing of seven cosmid clones that covered the entire gene revealed 32 exons (not including one exon involved in the insertion/deletion polymorphism), spanning approximately 140 kb of genomic DNA. These results may contribute to an understanding of the mechanism causing chromosomal translocations in leukemic cells.

Efficacy of immunization of high-risk infants against hepatitis B virus evaluated by polymerase chain reaction

The polymerase chain reaction (PCR) is a rapid and very sensitive method to detect viral genomes. In the present study, the efficacy of immunization against hepatitis B virus (HBV) of high-risk infants was evaluated by PCR. Twenty-nine infants born to 24 HBeAg-positive carrier mothers were given hepatitis B immune globulin (HBIG) at birth and thereafter received repeated inoculations of plasma-derived vaccine or HBIG, or both, within 1 year. Serum samples at 1 year following immunization were stored at -40 degrees C for later analysis using PCR to detect HBV-DNA. When HBV genomes were detected in infants, the DNA sequences in the S gene of HBV were determined. Of 29 infants, 2 were positive for HBV-DNA at the 1 year following immunization; one had the HBV containing only the wild-type sequence in the S gene and became negative for HBV-DNA during the follow-up period. In contrast, another had the HBV, which contained nucleotide substitutions that altered the expression of the common group-specific determinant "a" of the S gene and resulted in clinical hepatitis with viral persistence. PCR analysis suggests that immunization against HBV prevents effectively high-risk infants from mother-to-child transmission. Even then, however, it is possible that amino acid substitutions in the "a" determinant of the S gene are associated with failure of conventional immunization against HBV.

Roles of E- and P-cadherin in the human skin

The Ca(2+)-dependent cell-cell adhesion molecules, termed cadherins, are subdivided into several subclasses. E (epithelial)- and P (placental)-cadherins are involved in the selective adhesion of epidermal cells. E-cadherin is expressed on the cell surfaces of all epidermal layers and P-cadherin is expressed only on the surfaces of basal cells. Ultrastructural studies have shown that E-cadherin is distributed on the plasma membranes of keratinocytes with a condensation in the intercellular space of the desmosomes. During human skin development P-cadherin expression is spatiotemporally controlled and closely related to the segregation of basal layers as well as to the arrangement of epidermal cells into eccrine ducts. In human skin diseases E-cadherin expression is markedly reduced on the acantholytic cells of tissues in pemphigus and Darier's disease. Cell adhesion molecules are now considered to play a significant role in the cellular connections of cancer and metastatic cells. Reduced expression of E-cadherin on invasive neoplastic cells has been demonstrated for cancers of the stomach, liver, breast, and several other organs. This reduced or unstable expression of E- and P-cadherin is observed in squamous cell carcinoma, malignant melanoma, and Paget's disease, but cadherin expression is conserved in basal cell carcinoma. Keratinocytes cultured in high calcium produce much more intense immunofluorescence of intercellular E- and P-cadherin than those cells grown in low calcium. E-cadherins on the plasma membrane of the keratinocytes are shifted to desmosomes under physiological conditions, and therein may express an adhesion function in association with other desmosomal cadherins. Soluble E-cadherins in sera are elevated in various skin diseases including bullous pemphigoid, pemphigus vulgaris, and psoriasis, but not in patients with burns. Markedly high levels in soluble E-cadherin are demonstrated in patients with metastatic cancers.

Evaluation of soluble cell adhesion molecules in atopic dermatitis

Recent studies have indicated the importance of cell adhesion molecules (CAMs) between the vascular endothelium and activated leukocytes in various inflammatory skin diseases. Soluble forms of CAMs (sCAMs) have also been detected in sera from such diseases. In order to elucidate the role of the soluble forms in skin inflammation, we determined the serum levels of E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) in patients with atopic dermatitis (AD). Using an enzyme-linked immunosorbent assay, we quantified sCAMs levels in 21 patients with atopic dermatitis and in 16 healthy controls. In severe AD patients, levels of these three types of sCAMs were markedly elevated. sE-selectin was significantly elevated in severe AD over the levels in mild AD. A positive correlation with individual clinical activity was found for changes in the sE-selectin and sVCAM-1 levels. sE-selectin levels were correlated with the serum IgE levels and the number of eosinophils. The sVCAM-1 level was also significantly correlated with the number of monocytes. Among these three molecules, sE-selectin appeared to be the most sensitive clinical parameter in monitoring the clinical course of AD patients.

E- and P-cadherin expression in tumor tissues and soluble E-cadherin levels in sera of patients with skin cancer

The expression pattern of epithelial (E)- and placental (P)-calcium-dependent cell-cell adhesion molecules was examined immunohistochemically in various skin tumors. E- and P-cadherin expression was preserved in nodular and superficial types of basal cell carcinoma (BCC). In well-differentiated squamous cell carcinoma (SCC), E-cadherin on the cell surface of the tumor was reduced but expression of P-cadherin was preserved more frequently at the peripheral sites of the tumor than in the central sites of the tumor. Paget's cells and melanoma cells did not express E- or P-cadherins in the nest of the epidermis. Immunoreactive E-cadherin levels in sera were significantly elevated in patients with invasive Paget's disease, metastatic malignant melanoma and severe types of psoriasis and atopic dermatitis when compared with those of normal controls. Reduced or loss of cadherin in localized tumor cells may be correlated with the proliferation, and the level of soluble E-cadherin in circulation may be a marker in the extent of damaged skin by tumor and/or inflammation.

Malignant hemangioendothelioma

BACKGROUND

The administration of interleukin-2 (IL-2) has recently been reported to be favorable for treating malignant hemangioendothelioma (MHE).

METHODS

Two patients with MHE responded well to intralesional injections of recombinant IL-2 (rIL-2) without major side effects. The purpose of this study was to characterize cells infiltrating the regressing tumor following rIL-2 treatment. Immunohistochemical studies were performed on biopsy specimens taken from rIL-2-injected lesional skin.

RESULTS

It was shown that CD8+ lymphocytes and CD56+ natural killer (NK) cells infiltrated at the rIL-2-injection sites, suggesting that these cells contributed to the tumor regression. In addition, MHE cells bore intercellular adhesion molecule-1 (ICAM-1) whose expression was augmented by rIL-2 injections.

CONCLUSIONS

These findings suggested, that rIL-2 not only induces lymphokine-activated killer (LAK) cells and NK cells, but also facilitates these cytotoxic cells to adhere to MHE cells by enhancing ICAM-1 expression of tumor cells.

Cutaneous colonization with staphylococci influences the disease activity of Sézary syndrome: a potential role for bacterial superantigens

It has previously been shown that circulating Sézary cells respond in vitro to superantigenic staphylococcal exotoxins in a manner that is restricted by their V beta usage. This study was conducted to examine whether cutaneous colonization with Staphylococcus aureus influences the activity of the skin lesions of Sézary syndrome, and whether S. aureus isolated from patients with Sézary syndrome stimulates circulating Sézary cells in vitro. Two patients with Sézary syndrome, whose skin was colonized with S. aureus, were treated with antibacterial agents, and the relation between the severity of the skin disease and the degree of S. aureus colonization was assessed. In addition, the patients' peripheral blood mononuclear cells were cultured in the presence of mitomycin C-treated S. aureus or superantigenic staphylococcal toxins. The antibacterial treatment improved the skin disease, and eliminated S. aureus in both patients. In one patient, 98% of the peripheral blood mononuclear cells bore V alpha 2V beta 17 of the T-cell receptor, indicative of the presence of an extremely high percentage of circulating Sézary cells. The peripheral blood lymphocytes from this patient responded well in vitro to superantigenic staphylococcal enterotoxin (SE), but not to SEA or toxic shock syndrome toxin-1, or to mitomycin-treated S. aureus isolated from the same patient. Cutaneous colonization by S. aureus influences the disease activity of CTCL, possibly by activation of Sézary cells by bacterial superantigenic exoproteins.

Cadherins in cutaneous biology

The role of cadherins in cutaneous biology has focused mainly on the classical cadherins, E- and P-cadherin. In this review, roles for cadherins in skin morphogenesis, keratinocyte differentiation, and cancer metastasis are discussed. E-cadherin is expressed on the surfaces of whole epidermal layer cells, and P-cadherin is expressed only on the surfaces of basal cells. Ultrastructural studies have shown that E-cadherin is distributed on the cytoplasmic membranes of keratinocytes with a condensation in the intercellular space of the desmosomes. During human skin development, P-cadherin expression is spatiotemporally controlled and closely related to the segregation of basal layers as well as to the arrangement of epidermal cells into eccrine ducts. In human skin diseases, E-cadherin expression is markedly reduced on the acantholytic cells of tissues in pemphigus and also in Darier's disease. Keratinocytes cultured in high calcium produce a much more intense immunofluorescence of intercellular E- and P-cadherin than do cells grown in low calcium. Ultrastructural studies show that E-cadherin on the cytoplasmic membrane of the keratinocytes is shifted to desmosomes under physiological conditions and therein expresses an adhesion function is association with other desmosomal cadherins. Cell adhesion molecules are now considered to play significant roles in the cellular connections of cancers and metastatic cells. Reduced expression of E-cadherin on invasive neoplastic cells has been demonstrated for cancers of the stomach, liver, breast, and several other organs. This reduced expression of E-cadherin is observed in squamous cell carcinoma and Paget's disease. Soluble E-cadherins in sera are elevated in various skin diseases, including bullous pemphigoid, pemphigus vulgaris and psoriasis, but not in patients with burns. Markedly high levels in soluble E-cadherin are demonstrated in patients with metastatic cancers.

[Prevalence estimates for non-insulin dependent diabetes mellitus (NIDDM) in Japan from National Survey of Circulatory Disorders 1990 data]

Prevalence of diabetes mellitus in Japan was estimated from fructosamine and hemoglobin A1c measurement data obtained from the National Survey of Circulatory Disorders 1990, using a previously reported method which used the results of a screening test for estimating true prevalence. The prevalence for males was higher than that for females. The prevalences were less than 10% for those 49 years or younger and approximately 20% for those 50 years or older. The estimated values derived from fructosamine or hemoglobin A1c did not vary considerably.

Disseminated pagetoid reticulosis: need for long-term follow-up

A 54-year-old woman had an erythematous plaque on the left index finger for 2 years. Histologically there was a dense infiltrate of atypical mononuclear cells in the epidermis that produced a pagetoid appearance. A diagnosis of localized pagetoid reticulosis was made. Three years after total removal of the finger lesion, erythematous plaques appeared on her left thigh, followed by the development of similar plaques on the right thigh and lower abdomen. Histologically these skin lesions had the same pagetoid appearance as the plaque on the finger. This suggested development of the disseminated type of pagetoid reticulosis, long after removal of the initial skin lesion.

Pemphigus associated with metastatic carcinoid

Patients with pemphigus are occasionally associated with neoplasms. We report a case of pemphigus with carcinoid. To our knowledge, this is the first case of coexistence of pemphigus and carcinoid.

A case of bullous systemic lupus erythematosus

We report a case of bullous systemic lupus erythematosus (SLE). The patient suddenly presented with a widespread blistering eruption on the trunk and neck during the course of treatment of SLE. A skin biopsy specimen showed subepidermal blisters, and direct immunofluorescence (IF) revealed deposition of IgA, IgG and IgM at the dermoepidermal junction. Indirect IF showed linear IgG deposition along the base of 1 M NaCl-split skin. Rapid resolution of the blisters occurred following treatment with dapsone 50 mg daily.

[A method of estimation for prevalence of diabetes mellitus from fructosamine levels]

A method for estimating the prevalence interval of diabetes mellitus from fructosamine data is presented, which is based on the previously reported method for estimating prevalence from results of screening tests and on the results of 75 gram glucose tolerance test and fructosamine test in 1,359 examinees. Where true prevalences are 1-20% and population size is 100-10,000, the estimates for prevalence of diabetes mellitus are generally minimum when a screening level of 310 mumol/l of fructosamine is utilized. In our method, a screening level for fructosamine of 310 mumol/l was specified. Standard error ratios of estimated prevalence of diabetes mellitus to true prevalence in a population with an actual prevalence of 10% were about 40% for a population of 200 persons, and about 20% for 2,000 persons or more.

Local spread of HDV infection transiently occurring in Japan

Hepatitis B virus (HBV) carriers and patients with acute hepatitis B living in the Kamigoto islands, a part of Japan with a high incidence of HBV carriage, were retrospectively tested for serum anti-hepatitis D virus (anti-HDV) and they were compared with the inhabitants of Oita City (an area with an average HBV carriage rate). The prevalence of anti-HDV in HBV-infected individuals was 8.3% (42/507) in Kamigoto and 0% (0/101) in Oita City. With one exception, all of the positive serum samples in Kamigoto were collected before 1986, and the mean age of the positive individuals was significantly younger than that of the negative individuals (P < 0.005). Among the 42 anti-HDV-positive patients, nine (21%) had definite liver disease. The route of infection was uncertain in most cases (i.e. sporadic), but two pairs of mothers and children were detected. Although the prevalence of anti-HDV positivity in Japan has been reported to be very low (about 1% or less), the present investigation showed that the local spread of HDV infection in Kamigoto occurred on a minor scale up to 1986. The infections presumably resulted from the closed environment and the high incidence of HBV carriage in these islands. Accordingly, there could be a considerable risk of the outbreak of HDV infection in the future under similar conditions, even in countries where the disease has never been detected previously.