Photodynamic therapy induces less pain in patients treated with methyl aminolevulinate compared to aminolevulinic acid

Photodynamic therapy (PDT) with topical application of either aminolevulinic acid (ALA) or methyl aminolevulinate (MAL) is increasingly used for the treatment of actinic keratoses (AKs). Although PDT is a well-tolerated treatment, pain is the most severe side effect. Sixty-nine patients (mean age 69 years, 61 male, 8 female) suffering from multiple AKs on the scalp (field cancerization) were included in the study. PDT treatment was performed, using red light (Waldmann PDT 1200) with a light dose of 100 J/cm2 delivered at a dose rate of 160 mW/cm2. Either ALA or MAL were used as photosensitizer. Patients were asked to rate their pain on a scale from 0 to 10 (0 = no pain, 10 = unbearable pain). Upon reaching a score of 10 treatment was discontinued. Comparison of ALA and MAL in patients with AK revealed that MAL induced less pain than ALA. While 14% of the patients treated with MAL discontinued treatment before reaching the required light dose of 100 J/cm2, the number of patients treated with ALA who discontinued treatment reached 54%. PDT using MAL appears to be a better tolerated treatment for multiple AKs on the scalp compared to ALA-PDT. Differences in selectivity for tumor cells and transport of ALA in peripheral neurons may play a role.

Successful UVA1 phototherapy in a patient with scleredema adultorum

Scleredema adultorum is a rare connective tissue disorder of unknown cause. Both bath-PUVA and cream-PUVA therapy were reported to be effective. We describe a patient with scleredema adultorum who showed a striking clinical improvement with a medium-dose UVA1 phototherapy (single dose, 50 J/cm(2); 35 treatments).

"Melanoma inhibitory activity" (MIA): a promising serological tumour marker in metastatic uveal melanoma

PURPOSE

To assess the role of "melanoma inhibitory activity" (MIA) as a potential serum marker for screening and detection of metastatic uveal melanoma.

DESIGN

Prospective, clinical study.

MATERIAL AND METHODS

Serum samples of 305 patients with uveal melanoma were collected. Serum samples were analysed by a one-step enzyme-linked immunosorbent assay (ELISA) to quantify the MIA serum levels. All patients underwent a standardized echography of the globe to evaluate maximum tumour height and were checked for systemic metastasis of the tumour by liver enzyme tests and ultrasonography of the liver.

RESULTS

Twenty patients (6.6%) had proven metastatic disease; eight of them developed it during follow-up. The mean serum concentration of MIA in the 285 patients without metastasis was 6.72 ng/ml, whereas the mean serum concentration of MIA in the 20 patients with metastasis was 13.03 ng/ml (P<0.001). The eight patients who developed metastatic disease during follow-up showed an MIA of 5.92 ng/ml before detection of metastasis and 12.21 ng/ml afterwards (P<0.001). MIA serum levels did neither correlate with the tumour height or to whether local therapy had been applied.

CONCLUSION

The elevation of MIA serum levels in patients with metastatic disease from melanoma supports its promising role as a serum marker for monitoring patients with uveal melanoma.

A secreted form of P-cadherin is expressed in malignant melanoma

Cadherins are Ca-dependent homophilic cell-cell adhesion molecules which are responsible for correct location of cells and tissue integrity. They are critical for development and maintenance of epithelial architecture. Aberrantly expressed cadherins are known to be involved in malignant transformation of different types of tissues. In this study, we show the expression of a short truncated 50 kDa form of the N-terminal part of P-cadherin in seven melanoma cell lines compared to melanocytes and keratinocytes. In vitro protein analysis on cell culture supernatant as well as immunohistochemistry of primary and metastatic melanoma tissue revealed the expression of this short form of P-cadherin. Furthermore, analysis showed that this short 50 kDa form of P-cadherin is secreted by melanoma cells in contrast to the membrane bound form in melanocytes. Analysis on mRNA level detected only exon 1 to 10 of P-cadherin resulting in the 50 kDa form missing the transmembrane and cytoplasmatic region. Genomic sequence analysis did not show any mutations in melanoma cells neither in the exons nor in the exon-intron boundaries. Furthermore, there was no loss of exons 11-16 on the genomic level. Functionally, the secreted form of P-cadherin could play a role as regulator of the homophilic interaction between P-cadherin molecules by antagonizing their biological role acting as a dominant negative form to interrupt cell-cell attachment.

Patent foramen ovale and left atrial appendage: new devices and methods for closure

Transcatheter closure of atrial septal defects (ASDs) has become a routine procedure in many countries of the world. It spares many patients cardiac surgery and has proven efficacy in long-term studies. Device improvements have resulted in a continuous reduction of complications and of residual shunt frequency. ASD closure devices are also used for transcatheter closure of patent foramen ovale (PFO) for prevention of paradoxical embolism. In the past few years, there has been increasing interest in developing devices specifically designed for PFO closure. Although transcatheter closure of ASDs is well established, interventional closure of the left atrial appendage is in its development stage. Closure of the left atrial appendage is designed to reduce the risk of stroke in patients with atrial fibrillation in whom anticoagulation with Warfarin-type drugs is contraindicated. This article describes the latest developments in catheter closure of PFO and the left atrial appendage.

Elevated MIA levels in the serum of pregnant women and of children

Recent studies have shown that the protein MIA (melanoma inhibitory activity) is a potent serum marker for malignant melanoma. MIA is expressed in chondrocytes at high levels, and might potentially be elevated during periods of growth in childhood. Therefore, we evaluated MIA serum levels in pregnant women and in growing children. We found that no significant enhancement of MIA serum levels was apparent until 38 weeks of pregnancy. Starting at 38 weeks, a significant increase was noted. The study further revealed that children and teenagers also have increased MIA serum levels. However, from the age of 17 years MIA serum levels are not different from those in healthy adults. In summary, MIA can be used as a serum marker for melanoma in adults starting at the age of 17 years. In pregnant women (> 38th week), children, and teenagers MIA should not be used in serum diagnostics for malignant melanoma until larger studies have been performed to generate cut-off levels for each group.

Laminin, hyaluronan, tenascin-C and type VI collagen levels in sera from patients with malignant melanoma

In this study, hyaluronan, laminin-1, tenascin-C and type VI collagen were measured in the sera of patients with stage I/II and stage IV melanoma. A significant increase in the serum levels of all four extracellular matrix proteins was found in patients with stage IV melanoma compared to healthy donors. Type VI collagen and hyaluronan serum levels were also significantly increased in stage I/II melanoma. Increased expression of the four matrix proteins was also demonstrated in melanoma cell lines using reverse transcriptase- polmerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). We suggest that tenascin-C, hyaluronan, laminin-1 and type VI collagen are involved in melanoma development and extracellular matrix remodelling during melanoma progression. This finding will be of interest in the development of serum markers for progression of malignant melanoma.

Histopathological characteristics of small diameter melanocytic naevi

BACKGROUND/AIMS

The clinical definition of an atypical naevus ("dysplastic naevus" or "naevus with architectural disorder and cytological atypia of melanocytes") stresses size larger than 5 mm in diameter as a major diagnostic criterion. Because malignant melanomas and their precursors may arise in smaller lesions, a histological study of melanocytic lesions smaller than 4 mm in diameter was conducted to evaluate their histological appearance.

METHODS

Two hundred and sixty one naevi smaller than 4 mm in diameter were collected and characterised by histological examination into benign naevi without architectural disorder and naevi with architectural disorder and mild, moderate, and severe atypical melanocytes according to criteria used on larger lesions.

RESULTS

Small melanocytic naevi covered the same complex histological spectrum from benign naevi to severely atypical naevi when compared with larger lesions. A high proportion of small naevi (72%) exhibited features diagnostic for naevi with architectural disorder and cytological atypia.

CONCLUSION

There is a discrepancy between histological and clinically defined atypical naevi. The same generally accepted criteria for the histological diagnosis of atypical naevi should be used for small melanocytic naevi in addition to large ones. Thus, small naevi exhibiting atypical features on histological examination should be categorised as atypical naevi, regardless of their small diameter.

Linear spiradenoma with focal malignant transformation

Malignant spiradenoma is an exceedingly rare adnexal tumour clinically characterized by rapid enlargement of a pre-existing, long-standing benign spiradenoma. Microscopic examination typically reveals a continuum between benign spiradenoma and areas of malignant transformation. Biological behaviour is unpredictable and it should be regarded as a potentially lethal neoplasm. Treatment recommendations require radical surgical excision. The reported case of a 23-year-old female illustrates the malignant transformation of a 1.5 cm nodule within a large linear spiradenoma almost covering the frontal aspect of the lower leg. In reviewing the literature, malignant transformation seems to occur slightly more often in multiple than in solitary spiradenomas. It is unclear whether excision restricted to the malignant area is an advisable treatment option in comparison to total excision of all spiradenoma nodules. In the presented case, the transformed area was excised. The patient is free of recurrence after 2 years.

Chronic urticaria: impact of allergic inflammation

Urticaria is defined by weals (hives), with or without angioedema, that appear and peak in minutes to hours, usually disappear within 24 h, and are accompanied by pruritus that worsens during the night. Urticaria is caused by cutaneous mast cell degranulation, attributed to immunological, nonimmunological, and idiopathic causes. Chronic idiopathic urticaria (CIU) is the diagnosis when the pathophysiological mechanism of persistent urticaria remains unclear; up to half of patients with CIU have functional autoantibodies directed against the high-affinity receptor for IgE (FcepsilonRI) or against IgE itself, which appear to induce mast cell degranulation. Systemic histamine H1-receptor antagonists, such as desloratadine, are central to the management of CIU. The efficacy and safety of desloratadine, 5 mg once daily, was studied in a double-blind, randomized, placebo-controlled, multicentre trial that included 190 patients, ages 12 and above, with at least a 6-week history of CIU and experiencing a flare of at least moderate severity. Desloratadine was superior to placebo in controlling pruritus and total symptoms after the first dose, and its superiority was maintained throughout the full 6 weeks of the study. Measures of sleep, daily activity, therapeutic response, and global CIU status were also significantly improved with desloratadine after the first dose and maintained throughout the study.

UV-induced skin changes due to regular use of commercial sunbeds

BACKGROUND/AIM

Increased pigmentation and thickening of the epidermis are the most important photoprotective skin reactions induced by ultraviolet (UV) radiation. The present study was designed to find out what changes are induced by regular use of commercial sunbeds twice weekly over a period of 6 weeks.

METHODS

The parameters analysed were skin pigmentation measured by chromametry, minimal erythema dose (MED) as a parameter of light sensitivity, epidermal thickening as determined by histology, induction of keratinocyte apoptosis as determined by TUNEL staining and antioxidant metabolism as measured by changes of cis- and trans-urocanic acid (UCA) content of the skin.

RESULTS

As expected, chromametry confirmed the clinically obvious increased skin pigmentation. However, no increase in MED was observed. In addition, neither epidermal thickening nor sunburn cells were seen. Significant detectable changes in proportion of the UCA isomer content of the UV-exposed skin were seen. The total UCA and cis-UCA content increased significantly between nearly all points of measurement. The amount of trans-UCA first decreased, then increased significantly between the different time points.

CONCLUSION

Our data indicate that sunbed-induced tanning is non-protective, which has to be addressed for persons looking for this effect before planning a stay in a sunny climate. However, sunbed-induced tanning may influence immunological reactions.

[Keratosis lichenoides chronica. Bath PUVA therapy]

We describe the case of a 51-year-old male patient with characteristic lesions of keratosis lichenoides chronica confined to the back of his hands and feet. The lichenoid papules, linear hyperkeratotic ridges and erythematosquamous plaques appeared first in early childhood and recurred after a short episode of spontaneous remission. They didn't respond to various topical treatment modalities over the years. After a local PUVA therapy all lesions disappeared with no recurrence for over two years now. Our case report indicates a new promising indication for bath-PUVA-therapy.

[Scrotal leiomyoma]

Genital leiomyomas of the scrotal skin are extremely rare benign tumors, originating from the tunica dartos of the scrotum. We describe a 55-year-old caucasian male with a 3-year history of a slowly growing asymptomatic scrotal knot which was first clinically regarded as a cyst and finally diagnosed histopathologically as leiomyoma. This typical case demonstrates that leiomyomas should be considered in the differential diagnosis of scrotal tumors.

[Cylindrospiradenomas in Brooke-Spiegler syndrome]

Brooke-Spiegler syndrome is a rare autosomal-dominant inherited disease, characterized by the development of multiple cylindromas and trichoepitheliomas. We report a case in which tumors were found on the head showing histological features of both cylindromas and spiradenomas. These changes were in continuity within the same lesions. Since cylindromas are thought to be apocrine in nature, whereas spiradenomas are eccrine, a contiguous growth within the same neoplasm indicates a conflict concerning their histogenesis. The available histological, ultrastructural and immunohistochemical studies have not produced any criteria to allow an unequivocal classification, suggesting instead that both tumors arise from similarly differentiated cells, perhaps from pluripotent epithelial cells. In our opinion, it seems impractical to strictly classify cylindromas and spiradenomas into tumors of apocrine or eccrine differentiation. Moreover, at least for those cases of Brooke-Spiegler syndrome, where both tumors are found in immediate vicinity to each other, we propose the term cylindrospiradenoma.

Functional role of melanoma inhibitory activity in regulating invasion and metastasis of malignant melanoma cells in vivo

MIA (melanoma inhibitory activity) has been previously isolated from the tissue culture supernatant of melanoma cell lines as an autoregulatory activity, inhibiting thymidine incorporation. However, subsequent analyses of melanocytic tumours in vivo have correlated enhanced MIA expression with progression of melanocytic tumours, conflicting with the idea that MIA acts as a tumour suppressor. To investigate the role of MIA in vivo, we have therefore generated a panel of stably transfected B16 cell clones secreting different amounts of MIA. The capacity of these cell clones to form lung metastases in syngeneic C57Bl6 mice was strictly correlated to the level of MIA secretion, but the clones did not differ with respect to their proliferation in vitro. In summary, we suggest that MIA plays a causal role in promoting the metastasis of malignant melanomas, involving inhibition of tumour cell attachment to extracellular matrix molecules within their local milieu.

Role of the ATP synthase alpha-subunit in conferring sensitivity to tentoxin

Tentoxin, produced by phytopathogenic fungi, selectively affects the function of the ATP synthase enzymes of certain sensitive plant species. Binding of tentoxin to a high affinity (K(i) approximately 10 nM) site on the chloroplast F(1) (CF(1)) strongly inhibits catalytic function, whereas binding to a second, lower affinity site (K(d) > 10 microM) leads to restoration and even stimulation of catalytic activity. Sensitivity to tentoxin has been shown to be due, in part, to the nature of the amino acid residue at position 83 on the catalytic beta subunit of CF(1). An aspartate in this position is required, but is not sufficient, for tentoxin inhibition. By comparison with the solved structure of mitochondrial F(1) [Abrahams, J. P., Leslie, A. G. W., Lutter, R., and Walker, J. E. (1994) Nature 370, 621-628], Asp83 is probably located at an interface between alpha and beta subunits on CF(1) where residues on the alpha subunit could also participate in tentoxin binding. A hybrid core F(1) enzyme assembled with beta and gamma subunits of the tentoxin-sensitive spinach CF(1), and an alpha subunit of the tentoxin-insensitive photosynthetic bacterium Rhodospirillum rubrum F(1) (RrF(1)), was stimulated but not inhibited by tentoxin [Tucker, W. C., Du, Z., Gromet-Elhanan, Z. and Richter, M. L. (2001) Eur. J. Biochem. 268, 2179-2186]. In this study, chimeric alpha subunits were prepared by introducing short segments of the spinach CF(1) alpha subunit from a poorly conserved region which is immediately adjacent to beta-Asp83 in the crystal structure, into equivalent positions in the RrF(1) alpha subunit using oligonucleotide-directed mutagenesis. Hybrid enzymes containing these chimeric alpha subunits had both the high affinity inhibitory tentoxin binding site and the lower affinity stimulatory site. Changing beta-Asp83 to leucine resulted in loss of both inhibition and stimulation by tentoxin in the chimeras. The results indicate that tentoxin inhibition requires additional alpha residues that are not present on the RrF(1) alpha subunit. A structural model of a putative inhibitory tentoxin binding pocket is presented.

Desloratadine in the treatment of chronic idiopathic urticaria

Chronic idiopathic urticaria (CIU) is a common dermatologic disorder that may severely impair quality of life. Patients may suffer symptoms such as pruritus and disfigurement due to wheals for years or decades. Advances have been made in the last 10 years with the identification of an autoimmune pathogenesis in a significant proportion of patients. Despite this, treatment remains symptomatic, and antihistamines are the first choice of therapy once the diagnosis of CIU has been established. The goal of treatment is rapid, long-lasting symptom relief, and currently available antihistamines fail to provide this in many cases. Desloratadine is a novel, potent H1-receptor antagonist with additional inhibitory effects on inflammatory mediators such as cytokines and adhesion molecules. Newly published data on the efficacy and safety of desloratadine in CIU is highly encouraging, suggesting that the drug may improve symptom control above that currently available.

Melanoma inhibitory activity (MIA), a serological marker of malignant melanoma

Melanoma inhibitory activity (MIA) was originally identified as an 11 kDa protein secreted from malignant melanoma cells. We have shown that MIA is strongly expressed in melanoma and melanoma cell lines but not in melanocytes and normal skin. We also observed that MIA mRNA expression correlates with progressive malignancy of melanocytic tumors. Measuring MIA in serum or plasma by a sensitive and quantitative ELISA and investigating the potential of MIA serum levels as a novel marker for malignant melanomas showed that the protein can be used to monitor therapy and follow-up. The present study measured the variations in blood concentrations of MIA in 84 patients with stage II-IV melanoma by ELISA. Patients treated with repeated injections of a polyvalent melanoma vaccine (PMV), interferon-alpha-2b (IFN-alpha 2b) or interleukin-2 (IL-2) were followed during treatment duration. Before treatment, patients treated with PMV or IFN-alpha 2b had comparable low MIA concentrations, whereas most IL-2-treated patients had higher MIA levels. At the end of treatment, MIA concentrations were higher in patients with progressive disease (PD) than in patients with no clinical evidence of melanoma (NPD) for PMV, IFN-alpha 2b or IL-2 therapy (3.7 +/- 0.2 vs 11.5 +/- 5.4 ng/ml, 3.8 +/- 0.2 vs 8.3 +/- 1.7 ng/ml, and 2.3 +/- 0.7 vs 20.2 +/- 7.4 ng/ml, respectively, p < 0.05). In contrast to the stable MIA concentrations measured in NPD patients, significant increase in MIA levels were observed in PD patients over time regardless of treatment. For PMV- and IFN-alpha 2b-treated patients, a rise in MIA levels occurred significantly earlier than clinical diagnosis of melanoma recurrence. In conclusion, our data suggest that quantitation of MIA serum levels may be used for detection of both clinically apparent and non-apparent metastatic melanoma disease and for monitoring therapy.

Interlaboratory evaluation of a new reverse transcriptase polymerase chain reaction-based enzyme-linked immunosorbent assay for the detection of circulating melanoma cells: a multicenter study of the Dermatologic Cooperative Oncology Group

PURPOSE

Reverse transcription-polymerase chain reaction (RT-PCR)-based detection of tyrosinase mRNA is the most frequently used laboratory method for the detection of circulating tumor cells in melanoma patients. However, previously published results showed considerable variability in the PCR positivity rates.

MATERIALS AND METHODS

We designed a collaborative study to assess the sensitivity, specificity, and clinical relevance of a new standardized RT-PCR-based enzyme-linked immunosorbent assay (ELISA) for the detection of circulating melanoma cells. Blood samples of healthy donors mixed with cells of a melanoma cell line were prepared in a blinded fashion, and aliquots were sent to seven participating laboratories experienced in RT-PCR.

RESULTS

The results demonstrate a high sensitivity (1 melanoma cell/mL blood) and specificity (no false-negatives and 7.4% [2 of 28] false-positives) of the assay and a satisfactory rate of interlaboratory reproducibility. The analysis of aliquots of blinded samples derived from 60 melanoma patients identified tyrosinase mRNA in 17 of 60 (28.3%): three (20%) of 15 stage I patients, two (13.3%) of 15 stage II patients, five (35.7%) of 14 stage III patients, and seven (43.8%) of 16 stage IV patients. The interlaboratory reproducibility of positive samples, however, was extremely low and indicates the presence of low amounts of target mRNA.

CONCLUSION

Reverse transcriptase-PCR ELISA has a high sensitivity and specificity for the detection of tyrosinase mRNA in peripheral blood cells. The low interlaboratory reproducibility for the detection of tumor cells in blood samples of melanoma patients, however, raises the question of relevance of this assay for clinical use.

Comparison of two prognostic markers for malignant melanoma: MIA and S100 beta

It has recently been shown that the serum level of melanoma-inhibitory protein (MIA) provides useful information for the therapy and follow-up of patients with malignant melanoma. Previously, S100 beta has been described as a useful tumor marker for malignant melanoma. In this study, we compare the significance of the two markers in follow-up, therapy outcome and prognosis by measuring MIA and S100 beta serum levels in 50 melanoma patients. Serum levels were measured in patients with malignant melanomas of stages I-IV with at least 3 time points of measurement. Serial MIA and S100 beta measurements were obtained from 32 patients with stage IV disease in parallel to chemotherapy and from 18 patients with a history of stage I and stage II disease during follow-up. The response to chemotherapy in stage IV disease and relapse of melanoma during follow-up correlated with changes in MIA and S100 beta serum levels. In comparison, MIA revealed slightly higher specificity and sensitivity. In conclusion, both markers are useful for detection of progression from localized to metastatic disease during follow-up and for monitoring therapy of advanced melanomas.

Once-daily desloratadine improves the signs and symptoms of chronic idiopathic urticaria: a randomized, double-blind, placebo-controlled study

BACKGROUND

Chronic idiopathic urticaria (CIU) is the most common type of chronic urticaria, and pruritus is the most prominent symptom. Antihistamines are the first-line treatment for CIU. Sedation and anticholinergic adverse effects are often experienced with the first-generation antihistamines and there is a risk of cardiovascular adverse effects and drug interactions with some second-generation agents. Hence, new treatment options are needed. Desloratadine is a new, potent, nonsedating antihistamine that has an excellent cardiovascular safety profile.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled study designed to determine the efficacy and safety of desloratadine in the treatment of moderate-to-severe CIU. A total of 190 patients, aged 12-79 years, with at least a 6-week history of CIU and who were currently experiencing a flare of at least moderate severity, were randomly assigned to therapy with desloratadine 5 mg or placebo once daily for 6 weeks. Twice daily, patients rated the severity of CIU symptoms (pruritus, number of hives, and size of largest hive), as well as the impact of CIU symptoms on sleep and daily activity. Patients and investigators jointly evaluated therapeutic response and overall condition. Safety evaluations included the incidence of treatment-emergent adverse events, discontinuations due to adverse events, and changes from baseline in vital signs, laboratory parameters, and ECG intervals.

RESULTS

Desloratadine was superior to placebo in controlling pruritus and total symptoms after the first dose and maintained this superiority to the end of the study. Measures of sleep, daily activity, therapeutic response, and global CIU status were also significantly better with desloratadine after the first dose; these clinical benefits were also maintained throughout the 6-week study. No significant adverse events occured.

CONCLUSIONS

Desloratadine 5 mg daily is a safe and effective treatment for CIU with significant benefits within 24 h and maintained through the treatment period.

MIA as a reliable tumor marker in the serum of patients with malignant melanoma

BACKGROUND

Reports published in 1996 concerning the protein MIA proposed it as a useful tumor marker for patients suffering from malignant melanoma. Therefore we systematically started to measure MIA levels in patients with malignant melanoma. It was and still is questionable whether MIA in the serum of melanoma patients is a reliable tumor marker in terms of course of disease, therapy-monitoring and prognostic value. Previous studies have already confirmed the specifity of MIA as a tumor marker for malignant melanoma.

MATERIALS AND METHODS

Using an ELISA- System, we examined over 830 blood samples of 326 melanoma patients. The cut-off was determined at 9.8 ng/ml.

RESULTS

5.6% (n = 17) of melanoma patients at stage I/II (n = 302) showed increased MIA levels, whereas at stage III/IV (n = 5/n = 19) high levels were found in 60.0% and 89.5% respectively. Patients at stage III/IV with MIA levels below the cut-off turned out to be the ones after metastatic surgery, irradiation or chemotherapy. None of these patients developed further metastases during follow-up, just as patients at stage I/II without increased MIA levels. After a distinct rise of MIA levels, metastases could be detected at the same time or shortly after. On the other hand we saw decreasing levels after or during therapy.

CONCLUSION

Our data showed that MIA is a suitable serum marker to detect metastases and to monitor course and therapy of disease. The prognostic value (increased MIA levels at stage I/II), however, requires further investigation.

Important subunit interactions in the chloroplast ATP synthase

General structural features of the chloroplast ATP synthase are summarized highlighting differences between the chloroplast enzyme and other ATP synthases. Much of the review is focused on the important interactions between the epsilon and gamma subunits of the chloroplast coupling factor 1 (CF(1)) which are involved in regulating the ATP hydrolytic activity of the enzyme and also in transferring energy from the membrane segment, chloroplast coupling factor 0 (CF(0)), to the catalytic sites on CF(1). A simple model is presented which summarizes properties of three known states of activation of the membrane-bound form of CF(1). The three states can be explained in terms of three different bound conformational states of the epsilon subunit. One of the three states, the fully active state, is only found in the membrane-bound form of CF(1). The lack of this state in the isolated form of CF(1), together with the confirmed presence of permanent asymmetry among the alpha, beta and gamma subunits of isolated CF(1), indicate that ATP hydrolysis by isolated CF(1) may involve only two of the three potential catalytic sites on the enzyme. Thus isolated CF(1) may be different from other F(1) enzymes in that it only operates on 'two cylinders' whereby the gamma subunit does not rotate through a full 360 degrees during the catalytic cycle. On the membrane in the presence of a light-induced proton gradient the enzyme assumes a conformation which may involve all three catalytic sites and a full 360 degrees rotation of gamma during catalysis.

Hybrid Rhodospirillum rubrum F(0)F(1) ATP synthases containing spinach chloroplast F(1) beta or alpha and beta subunits reveal the essential role of the alpha subunit in ATP synthesis and tentoxin sensitivity

Trace amounts ( approximately 5%) of the chloroplast alpha subunit were found to be absolutely required for effective restoration of catalytic function to LiCl-treated chromatophores of Rhodospirillum rubrum with the chloroplast beta subunit (Avital, S., and Gromet-Elhanan, Z. (1991) J. Biol. Chem. 266, 7067-7072). To clarify the role of the alpha subunit in the rebinding of beta, restoration of catalytic function, and conferral of sensitivity to the chloroplast-specific inhibitor tentoxin, LiCl-treated chromatophores were analyzed by immunoblotting before and after reconstitution with mixtures of R. rubrum and chloroplast alpha and beta subunits. The treated chromatophores were found to have lost, in addition to most of their beta subunits, approximately a third of the alpha subunits, and restoration of catalytic activity required rebinding of both subunits. The hybrid reconstituted with the R. rubrum alpha and chloroplast beta subunits was active in ATP synthesis as well as hydrolysis, and both activities were completely resistant to tentoxin. In contrast, a hybrid reconstituted with both chloroplast alpha and beta subunits restored only a MgATPase activity, which was fully inhibited by tentoxin. These results indicate that all three copies of the R. rubrum alpha subunit are required for proton-coupled ATP synthesis, whereas for conferral of tentoxin sensitivity at least one copy of the chloroplast alpha subunit is required together with the chloroplast beta subunit. The hybrid system was further used to examine the effects of amino acid substitution at position 83 of the beta subunit on sensitivity to tentoxin.

[Henoch-Schönlein purpura: successful treatment with Dapsone]

A 26-year old patient who suffered from purpura for four years evolved into the complete clinical picture of Henoch-Schönlein-purpura in the past two years. A causative agent was never found. Multiple therapeutic approaches including systemic steroids, azathioprine as well as pentoxyfylline failed to control the arthralgias, intestinal symptoms and skin lesions. Therefore dapsone therapy was initiated at a dosage of 100 mg daily after checking the glucose-6-phosphate-dehydrogenase and with regular control of the blood methemoglobin level. Within two weeks, the patient's symptoms completely cleared, he has now been in remission for the past six months. As noted elsewhere, dapsone is an effective therapy for severe cases of Henoch-Schönlein- purpura.

MIA, a novel serum marker for progression of malignant melanoma

MIA was isolated previously as a small soluble protein secreted from malignant melanoma cell lines in vitro. Highly restricted expression patterns in melanocytic tumors were identified in vivo. We therefore quantitated serum levels of MIA protein by means of a non-radioactive ELISA and investigated whether MIA provides clinically relevant parameters in patients with malignant melanomas. Here we report enhanced MIA serum levels in 13% and 23% of patients with stage I and II disease, respectively, and in 100% with stage III or IV disease. Response to therapy in stage IV disease correlated with changes in MIA serum levels and surgical removal of metastases led to normalization of serum values. Repeated measuring of sera from 350 patients with a history of stage I or II melanoma during follow-up, we detected 32 patients developing positive MIA values. At the time of serum analysis 15 of them had developed metastases and one presented with metastatic disease 6 months later. In conclusion, MIA represents a novel serum marker for systemic malignant melanoma revealing the highest sensitivity and specificity among currently available markers.

[Clinical and epidemiological data of patients with malignant melanoma from the Munich Tumor Center 1977-1997]

Since 1997, data of patients with malignant melanomas have been systematically documented in the tumor registry of the Tumor Center Munich. Analysis of data of 8071 patients revealed that tumor thickness has steadily declined over the years. While in 1977 the median tumor thickness was 1.45 mm, it is now 0.75 mm. This has been followed by a significant improvement in overall survival. Males and older patients tend to have thicker melanomas than females and younger patients. There has been a relative increase of melanomas of the trunk. At diagnosis, 95% of patients had local disease. Of these patients, 18.3% developed metastastes. At least two-thirds of these patients had progression at the primary tumor site or the regional lymph nodes, both of which can be assessed by clinical or ultrasound examinations. Overall survival of patients with thin melanomas is excellent and does not differ substantially from the overall survival of the general population comparable in sex and age.

Detection of melanoma cells in the blood of melanoma patients by melanoma-inhibitory activity (MIA) reverse transcription-PCR

The detection of tumor-specific mRNA transcripts in the blood of patients by reverse transcription (RT)-PCR has been used as a very sensitive technique for determining systemically disseminated tumor cells. On the basis of previous expression studies, we aimed to trace melanoma cells in the blood of melanoma patients by RT-PCR of melanoma-inhibitory activity (MIA) mRNA. To detect sensitively MIA transcripts in total RNA isolated from peripheral blood mononuclear cells (PBMCs), we established a sensitive PCR-ELISA system. With this assay, we detected one melanoma cell in 2 ml of blood by a single round of 32 PCR cycles. A total of 295 PBMC samples isolated from 166 patients with melanocytic tumors were tested with the MIA RT-PCR-ELISA: (a) 58 patients (99 samples) with malignant melanomas in stage I; (b) 49 patients (65 samples) with malignant melanomas in stage II; and (c) 47 patients (116 samples) with metastasized melanomas (stages III and IV), with an additional 12 patients (15 samples) with benign melanocytic nevi. Forty-four (26.8%) of 164 samples isolated from patients with melanomas in stages I and II were positive for MIA mRNA; in stages III/IV, 33 (28.4%) of 116 samples of patients, irrespective of clinically evident disease, were positive. Eleven (84.6%) of 13 PBMC samples from patients with metastasized melanoma and clinically evident disease without treatment were MIA mRNA-positive in contrast to only 19 (25.7%) of 74 samples isolated from patients in stage IV with metastasis during chemotherapy. Furthermore, none of the 16 PBMC samples of patients in stage IV without clinically detectable metastases at that time point during chemotherapy was MIA mRNA-positive. Interestingly, of the 44 positive samples (26.8%) isolated from patients with melanomas in stages I and II, 20 were still positive when retested after complete excision of the tumor. Our results reveal that amplification of MIA mRNA from the PBMCs of patients with malignant melanomas by PCR-ELISA provides a useful means to detect tumor cells in the systemic blood circulation. A correlation between positive blood samples and tumor burden in stages III and IV was detected, and, in addition, a significant effect of chemotherapy with respect to the reduction of the number of systemically spread tumor cells was observed. However, MIA amplification seems to be of little value as a surrogate marker for clinical staging or the detection of metastatic disease.

In situ expression patterns of melanoma-inhibiting activity (MIA) in melanomas and breast cancers

Elevated levels of melanoma-inhibiting activity (MIA) were measured previously in the serum of patients with metastasized melanomas and in a subgroup of patients with advanced-stage breast cancers. This study aimed therefore to visualize in situ expression patterns of MIA protein and mRNA in melanomas and breast cancers by means of immunohistochemistry, reverse transcription-polymerase chain reaction (RT-PCR), and in situ hybridization. Analysis of a panel of seven common melanocytic naevi, ten cutaneous melanomas, and 12 melanoma metastases detected high levels of both mRNA and protein in all melanomas and metastases, but only very low mRNA levels in three of seven naevi. Compared with the expression of pMel (HMB-45), tyrosine, and S-100 in these tumours, these results show that MIA provides a novel and sensitive marker for neoplastic melanocytes. Expression was not detected in other skin tumours including basal cell cancers and squamous cell cancers, nor in normal melanocytes and keratinocytes. MIA expression in adenocarcinomas was further studied in a panel of 20 specimens obtained from 16 advanced-stage breast cancers and four metastases. Significant levels of mRNA were detected in 17 of the 20 specimens and low levels in the other three tumours. Immunostaining visualized specific protein expression in the tumour cells of all 20 cancer specimens. These investigations define for the first time in situ expression patterns of MIA in melanomas and breast cancers and suggest a much broader expression in malignant epithelial neoplasms than previously determined by serum studies.

MIA (melanoma inhibitory activity): a potential serum marker for rheumatoid arthritis

OBJECTIVE

MIA (melanoma inhibitory activity) is correlated with metastasis in patients with malignant melanoma. As MIA is not only produced by melanoma cells, but also by differentiated chondrocytes, we examined whether serum levels of MIA are correlated with inflammation and/or joint destruction in rheumatic diseases.

METHODS

MIA serum concentrations of patients with different rheumatic diseases were examined and compared with healthy individuals and malignant melanoma patients. In addition, MIA concentrations were correlated to inflammatory parameters and joint destruction.

RESULTS

Increased MIA serum concentrations were found only in patients with rheumatic diseases associated with joint destruction, such as rheumatoid arthritis (RA), osteoarthritis, HLA B27-associated oligoarthritis, and psoriatic arthritis. Of these rheumatic diseases, a significant increase in MIA serum concentrations was seen only in patients with RA, associated with rheumatoid factor (RF) positivity and joint destruction.

CONCLUSIONS

In addition to RF, MIA might therefore be useful in the differential diagnosis of RA vs non-destructive rheumatic diseases, and the presence of elevated levels of MIA in serum very likely reflects joint destruction in RA.

[MIA ("melanoma inhibitory activity"). Biological functions and clinical relevance in malignant melanoma]

The protein MIA was identified and isolated from the tissue culture supernatant of melanoma cells in vitro by its ability to inhibit thymidine incorporation by melanoma cell lines. After purification and partial sequencing of the peptide, a fragment of the MIA cDNA was cloned by RT-PCR. This cDNA fragment was used to screen phage libraries and subsequently fully encoding human and murine MIA cDNA and genomic DNA clones were obtained. The MIA gene spans a region of approximately 2 kb and is divided into 4 exons. Mapping the MIA gene revealed that the human gene is located on chromosome 19 and the murine gene on chromosome 7. The MIA open reading frame spans 131 (human) or 130 (murine) amino acids. The first 24 (human) or 23 (murine) amino acids represent a signal sequence directing the secretion of MIA into the extracellular compartment. The mature, secreted MIA consists of 107 amino acids and its MW is approximately 11 kDa. Preliminary structural data suggests that MIA is a small globular protein stabilized by two intramolecular disulfide bonds. Expression studies of protein und mRNA levels indicate that MIA is expressed specifically by malignant melanoma cells and chondrocytes. This points to a highly restricted expression pattern which is controlled by the MIA promoter. In addition, MIA provides a clinically useful parameter in patients with malignant melanoma. Enhanced values were measured in the serum of all patients with metastatic melanoma (stage III and IV). In vitro and in vivo experiments using recombinant MIA protein revealed that MIA specifically inhibits attachment of melanoma cells to fibronectin and laminin. Further analysis indicated a direct binding between MIA and the matrix proteins. This finding provides an explanation for the capability of MIA to inhibit proliferation of melanoma cells in vitro. Our studies suggest a putative function of MIA in regulated detachment of melanoma cells from the extracellular matrix which is an important step in metastasis.

In vitro modulation of human melanoma cell invasion and proliferation by all-trans-retinoic acid

Invasive growth and formation of metastases involve complex interactions between tumour cells, host cells and components of the extracellular matrix. Retinoids, a group of vitamin A derivatives, modulate cell growth and differentiation and have been found to suppress tumour cell invasion in vitro and formation of metastases in vivo. The aim of our study was to investigate changes in proliferation and invasion through membrane barriers in vitro of seven human melanoma cell lines, established from human primary melanomas or metastases, in response to treatment with retinoic acid (RA). These changes were compared with the expression regulation of molecules that have been identified as targets of RA-mediated signal pathways. Invasiveness in vitro was correlated with the origin of the cell lines and was significantly higher in the lines derived from metastases. In all the cell lines proliferation and chemotaxis were inhibited by 10(-5) M RA, but the cell lines established from metastases were significantly more sensitive with respect to inhibition of invasion by RA. The specific expression patterns of MMP-1 and TIMP-2 were detected and regulated by RA in almost all cell lines, whereas expression of MMP-2 and TIMP-1 was not influenced by RA treatment. The most striking difference between the cell lines was a strong downregulation of transforming growth factor-beta (TGF-beta) expression in cell lines derived from metastases when treated with RA in contrast to cell lines from primary melanomas. These data provide evidence that RA modulates growth, chemotaxis and invasion in a broad panel of melanoma cell lines derived both from primary non-metastasized melanomas and metastases. However, distinct molecular mechanisms are involved in mediating these effects.