Update on the use of ciclosporin in immune-mediated dermatoses

Immune-mediated dermatoses, such as psoriasis and atopic dermatitis, affect a significant proportion of the population. Although most cases are not life threatening, these diseases can have a profound effect on the sufferer's quality of life and that of their family. Systemic therapy, such as ciclosporin, is often indicated for severe or recalcitrant disease. The efficacy of ciclosporin in the treatment of psoriasis and atopic dermatitis has been established and clinical data also demonstrate its efficacy in treating less common but equally challenging conditions such as pyoderma gangrenosum, lichen planus, autoimmune bullous disease, recalcitrant chronic idiopathic urticaria and chronic dermatitis of the hands and feet. The risk of potential adverse events associated with ciclosporin is greatly reduced if current treatment and monitoring guidelines are followed.

Oral pimecrolimus in the treatment of moderate to severe chronic plaque-type psoriasis: a double-blind, multicentre, randomized, dose-finding trial

BACKGROUND

There is a need for safe and effective alternative treatments for patients with moderate to severe psoriasis.

OBJECTIVES

Pimecrolimus is a calcineurin inhibitor that is being investigated in oral form for the treatment of psoriasis.

PATIENTS AND METHODS

A double-blind, randomized, parallel-group, dose-finding study was performed. Healthy adult outpatients with moderate to severe chronic plaque-type psoriasis (n = 143) were randomized to receive oral placebo or pimecrolimus 10 mg, 20 mg or 30 mg twice daily (b.d.) for 12 weeks.

MAIN OUTCOME MEASURES

The Psoriasis Area and Severity Index (PASI) was used to assess clinical severity of psoriasis. Results were analysed at weeks 7 (primary endpoint) and 13. Safety was assessed by monitoring all adverse events, laboratory investigations (blood chemistry, urinalysis, haematology) and physical examinations.

RESULTS

The change from baseline in PASI at week 7 showed a dose-dependent effect. The differences between each of the two higher doses of pimecrolimus and placebo were statistically significant (P < 0.001; ANOVA). The mean percentage decreases from baseline in PASI in the placebo group and pimecrolimus 10 mg, 20 mg and 30 mg b.d. groups at week 7 were 3.1%, 22.2%, 51.3% and 54.0%, respectively. Most adverse events were of mild or moderate severity. The only adverse event to show a dose-response relationship was a transient feeling of warmth. No clinically relevant effects on laboratory parameters were observed, and no increase in skin infection with pimecrolimus was seen.

CONCLUSIONS

Oral pimecrolimus produces a dose-dependent reduction in psoriasis severity, with doses of 20 mg and 30 mg b.d. being the most effective and well tolerated.

Oral pimecrolimus in the treatment of moderate to severe chronic plaque-type psoriasis: a double-blind, multicentre, randomized, dose-finding trial

BACKGROUND

There is a need for safe and effective alternative treatments for patients with moderate to severe psoriasis.

OBJECTIVES

Pimecrolimus is a calcineurin inhibitor that is being investigated in oral form for the treatment of psoriasis.

PATIENTS AND METHODS

A double-blind, randomized, parallel-group, dose-finding study was performed. Healthy adult outpatients with moderate to severe chronic plaque-type psoriasis (n = 143) were randomized to receive oral placebo or pimecrolimus 10 mg, 20 mg or 30 mg twice daily (b.d.) for 12 weeks.

MAIN OUTCOME MEASURES

The Psoriasis Area and Severity Index (PASI) was used to assess clinical severity of psoriasis. Results were analysed at weeks 7 (primary endpoint) and 13. Safety was assessed by monitoring all adverse events, laboratory investigations (blood chemistry, urinalysis, haematology) and physical examinations.

RESULTS

The change from baseline in PASI at week 7 showed a dose-dependent effect. The differences between each of the two higher doses of pimecrolimus and placebo were statistically significant (P < 0.001; ANOVA). The mean percentage decreases from baseline in PASI in the placebo group and pimecrolimus 10 mg, 20 mg and 30 mg b.d. groups at week 7 were 3.1%, 22.2%, 51.3% and 54.0%, respectively. Most adverse events were of mild or moderate severity. The only adverse event to show a dose-response relationship was a transient feeling of warmth. No clinically relevant effects on laboratory parameters were observed, and no increase in skin infection with pimecrolimus was seen.

CONCLUSIONS

Oral pimecrolimus produces a dose-dependent reduction in psoriasis severity, with doses of 20 mg and 30 mg b.d. being the most effective and well tolerated.

The use of ciclosporin in psoriasis: a clinical review

Psoriasis is a chronic condition that shows variability in phenotype and severity. The disease can seriously compromise patients' quality of life, regardless of disease extent. Systemic treatment is indicated when lesional burden is extensive and/or frequently relapsing, and when quality of life is severely altered. Furthermore, surveys have indicated that patients are dissatisfied with their current topical or phototherapy. The efficacy of ciclosporin in the treatment of psoriasis is well established. However, widespread use of this drug has been limited by concerns over adverse effects, such as renal impairment, hypertension and the potential risk of malignancy. Data from many clinical trials designed to examine the efficacy and safety of long-term continuous and intermittent short-course (< 12 weeks) therapy are now available. Information from these studies has aided dermatologists in developing treatment guidelines. Intermittent short-course therapy is well tolerated, safe, and highly effective in sustaining disease control and promoting quality of life. Long-term continuous ciclosporin therapy may be useful in some patients with refractory psoriasis. If treatment guidelines are followed, the risk of nephrotoxicity and hypertension is low. Ciclosporin therapy is associated with an increased risk of non-melanoma skin cancer (mainly squamous cell carcinoma) when patients have been previously exposed to psoralen-ultraviolet A (PUVA). The incidence of non-skin malignancy shows no significant difference to that observed in the general population.

Ciclosporin in psoriasis clinical practice: an international consensus statement

The main recommendations for the use of ciclosporin in the management of psoriasis are: (i) intermittent short courses (average of 12 weeks duration) of ciclosporin are preferable; (ii) ciclosporin should be given in the dose range 2.5-5.0 mg kg(-1) day(-1) (doses greater than 5.0 mg kg(-1) day(-1) should only be given in exceptional circumstances); (iii) treatment regimens should be tailored to the needs of each patient; (iv) selection of patients should take into account psychosocial disability, as well as clinical extent of disease and failure of previous treatment; (v) each patient's renal function (as measured by serum creatinine) should be thoroughly assessed before and during treatment; (vi) each patient's blood pressure should be carefully monitored before and during treatment; (vii) adherence to treatment guidelines substantially reduces the risk of adverse events; (viii) long-term continuous ciclosporin therapy may be appropriate in a subgroup of patients; however, duration of treatment should be kept below 2 years whenever possible; and (ix) when long-term continuous ciclosporin therapy is necessary, annual evaluation of glomerular filtration rate may be useful to accurately monitor renal function.

Intermittent short courses of cyclosporine microemulsion for the long-term management of psoriasis: a 2-year cohort study

BACKGROUND

Cyclosporine is effective in psoriasis, but long-term continuous therapy may be limited by renal impairment and hypertension. Intermittent short courses of treatment should minimize side effects and improve the risk-benefit ratio.

OBJECTIVE

Our purpose was to assess the long-term efficacy and safety of intermittent short courses of the microemulsion formulation of cyclosporine (Neoral) in the management of chronic plaque psoriasis unresponsive to topical therapies.

METHODS

In a multicenter open cohort study, 76 subjects were treated intermittently over a 2-year period. Patients with chronic plaque psoriasis were treated with cyclosporine until clearance of psoriasis or for a maximum of 12 weeks. Patients were then randomized into two groups. Group A stopped cyclosporine abruptly, whereas group B had the dose reduced by 1 mg/kg per day each week until cessation, which was within 4 weeks. On relapsing, patients received further courses of cyclosporine. Intermittent treatment was continued in this way for 2 years.

RESULTS

There was no statistically significant difference in the percentage of time in remission during the 2-year period between patients randomized to stop cyclosporine abruptly (56.2%) and patients randomized to taper cyclosporine within 4 weeks (61.8%). The mean percentage of time that patients received treatment during the study was 40.5% for randomization group A, 46.2% for randomization group B, and 42.8% overall. The median time to relapse was 115.5 days after the first treatment course but became progressively shorter after multiple treatment courses. Mean blood pressure and serum creatinine levels did not show any clinically significant changes over time.

CONCLUSIONS

This study indicates that intermittent short courses of cyclosporine are effective in patients with moderate to severe psoriasis for up to 2 years while improving the safety profile relative to continuous cyclosporine monotherapy.

p53-dependent apoptosis in melanoma cells after treatment with camptothecin

Cutaneous malignant melanoma is a life-threatening cancer with poor prognosis due to a high metastasis potential. The main obstacle in treatment of metastatic melanoma is the resistance to chemotherapy. Recent studies indicated that apoptosis is a common mechanism of action for various cytotoxic agents. As p53 plays an important part in apoptosis, we investigated the role of p53 in chemosensitivity of melanoma cells. Previously, we found that melanoma cell lines containing wild-type p53 have significantly higher response rates to chemotherapy than cell lines with a mutant p53 gene. To confirm the role of p53 in melanoma chemosensitivity further, we transfected an expression vector, pED1, which carries a mutant p53 gene, into a wild-type p53 melanoma cell line, MMAN. We examined the effect of mutant p53 on camptothecin-induced apoptosis and the expression of genes which are known to be involved in apoptosis or drug resistance, such as bcl-2, bax, bak, p21waf1, and P-glycoprotein. Our results indicate that overexpression of the mutant p53 increased the growth rate of MMAN cells, reduced the sensitivity to camptothecin, and lowered drug-induced apoptosis by 2-3-fold. Flow cytometry indicated that the camptothecin-induced apoptosis is not associated with G1 arrest. Furthermore, camptothecin treatment reduced bcl-2 and P-glycoprotein expression in wild-type p53 MMAN cells, but not cells overexpressing mutant p53. These results demonstrate that p53 mutational status is a determinant of melanoma chemosensitivity. p53 may downregulate bcl-2 and P-glycoprotein to induce apoptosis in melanoma cells after chemotherapy.

Effect of retinoic acid on apoptosis and DNA repair in human keratinocytes after UVB irradiation

BACKGROUND

Skin cancer is extremely common. Epidemiological studies indicated that ultraviolet radiation (UV) is the primary cause for skin cancers, and that retinoic acid (RA) is able to inhibit this UV-induced skin carcinogenesis; however, the molecular mechanism of the anti-UV action of RA is unclear.

OBJECTIVE

The purpose of this study is to investigate if RA enhances the removal of UV-induced DNA damage.

METHODS

The effect of RA on UV-induced apoptosis and DNA repair was investigated by ELISA apoptosis assay and CAT assay.

RESULTS

Both all-trans-RA and 9-cis-RA did not promote UV-induced apoptosis nor the repair of UV-damaged DNA in human keratinocytes. Furthermore, RA did not induce the expression of p53.

CONCLUSION

The inhibition of RA on skin carcinogenesis is not due to enhanced removal of UV-damaged DNA. Therefore, RA does not inhibit skin cancer development at the initiation stage, but possibly at the promotion and progression stages.

Effect of N-acetylcysteine on UVB-induced apoptosis and DNA repair in human and mouse keratinocytes

The incidence of skin cancer is increasing rapidly, particularly in the Caucasian population. Epidemiological and experimental studies demonstrated that ultraviolet radiation (UVR) is the primary cause for the increasing incidence of skin cancer. It is well known that UV irradiation induces DNA damage. If the damage is not repaired or removed in time, it can lead to mutations and skin carcinogenesis. N-acetylcysteine (NAC) has been shown to be an effective protector against UVB-induced immunosuppression and to modulate the expression of some oncogenes and tumor suppressor genes. To test further the protective effect of NAC against UVR, we used both in vitro and in vivo models to investigate the effect of NAC on UVB-induced apoptosis and repair of DNA damage in human and mouse keratinocytes. Our data indicate that the intracellular glutathione level was increased after treatment with NAC at 10-20 mM but decreased with 40 mM NAC treatment due to the toxicity. At concentrations up to 20 mM NAC did not have a significant effect on UVB-induced apoptosis of cultured human keratinocytes. In addition, in an in vivo mouse model, topical application of NAC (3 mumol cm-2) that has been shown to inhibit UVB-induced immunosuppression did not have any effect on UVB-induced apoptosis and did not reduce the formation or enhance the repair of UVB-induced cyclobutane pyrimidine dimers and (6-4) photoproducts. Our results indicate that NAC is ineffective in preserving the genomic stability of keratinocytes against UVB irradiation.

Intermittent short courses of cyclosporin (Neoral(R)) for psoriasis unresponsive to topical therapy: a 1-year multicentre, randomized study. The PISCES Study Group

We performed a 1-year study to determine whether intermittent short courses of the microemulsion formulation of cyclosporin (Neoral) could effectively control plaque psoriasis and whether tapering or abrupt cessation of cyclosporin therapy would influence time to relapse. Four hundred patients with plaque psoriasis were included in this open, multicentre, randomized study. All patients commenced cyclosporin at a dose of 2.5 mg/kg daily. Cyclosporin dosage could be increased to a maximum of 5 mg/kg daily. Treatment was continued until clearance of psoriasis or for a maximum of 12 weeks. Patients were then randomly assigned either to stop cyclosporin abruptly or to have the dose reduced by 1 mg/kg daily each week until cessation. On relapse, patients were given another course of cyclosporin. Patients were followed for at least 1 year, during which they could receive as many treatment courses as necessary. The number of patients who required one, two, three and four treatment courses was 400, 259, 117 and 26, respectively. The median time to relapse after the end of the first treatment period was 109 days in the group of patients randomized to stop cyclosporin abruptly and 113 days in patients randomized to taper off cyclosporin (P = 0.038). More than 30% of patients had not relapsed 6 months after having stopped treatment. After each treatment course, the Kaplan-Meier probability of achieving 75% or more reduction in disease area by day 84 of treatment was 83%, 76%, 73% and 66%, respectively. Mean serum creatinine concentration and blood pressure did not show any clinically significant changes over time. Our results show that intermittent short-course therapy with Neoral, when used in conjunction with topical therapy, is well tolerated and provides effective control of plaque psoriasis for 1 year. Tapering off cyclosporin on treatment cessation induces a slight delay in psoriasis relapse.

Immunotherapy of malignant melanoma in a SCID mouse model using the highly cytotoxic natural killer cell line NK-92

In this work, we evaluated the potential of the natural killer (NK) cell line NK-92 and its IL-2-independent variants NK-92MI and CI, as immunotherapy for melanoma. In vitro, we found that NK-92 was much more cytotoxic to a number of human melanoma cell lines than lymphokine-activated killer (LAK) cells, particularly at low effector/target (E:T) ratios. In vivo treatment of mice challenged with MEWO melanoma cells with i.v. administered NK-92 and NK-92-MI resulted in a 1.5-2.5-fold increase in average length of survival. NK-92, MI, and CI were also effective against the WM1341 cell line, causing a 2-5-fold increase in survival when administered before the malignant cells. With s.c. injection, MEWO and WM1341 caused a primary tumor mass, secondary tumors, and metastatic cells. NK-92 cells reduced WM1341 primary tumor size by 40-90% and MEWO tumors by 30-75%. Similar results were seen with NK-92MI and CI. These data show that NK-92 cells are highly cytotoxic to human melanoma cells in vitro and in vivo and suggest that treatment with NK-92 cells may be a potentially effective immunotherapeutic modality in melanoma.

Expression of cell cycle regulators in human cutaneous malignant melanoma

We postulate that genes involved in the control of cell proliferation are important determinants of melanoma growth and/or transformation. Using Western blot analysis, we compared the expression of nine key cell cycle regulators in metastatic melanomas with that in benign acquired naevi. Among the cyclin-dependent kinases (CDKs) examined, CDK2 was consistently and significantly overexpressed (three- to eight-fold) in metastatic melanomas compared with naevi. CDK1 and CDK4 exhibited no significant difference in expression between benign naevi and metastatic melanomas. CDK6 expression was variable, with four out of 10 metastatic melanomas showing higher expression than naevi. All the cyclins examined, especially cyclins A and D, were expressed more in metastatic melanomas than in naevi. Cyclin E was not detected in benign naevi, but was easily detectable in most of the metastatic melanomas. In addition, there was significantly greater expression of CDC25A, a tyrosine phosphatase that activates CDK kinases, in the metastatic melanomas. Over-expression of CDK2, CDK6, CDC25A and cyclin A was confirmed in melanoma cell lines. These cell cycle regulators may play an important role in melanoma growth and/or transformation.

Ascomycins in dermatology

Ascomycin derivatives represent a novel class of anti-inflammatory macrolactams that are under development for the treatment of skin diseases. The main biological effect of ascomycins is a blockage of the synthesis of both Th1- and Th2-type cytokines in target cells. SDZ ASM 981 is the most advanced ascomycin derivative under development. It has high antiinflammatory activity in animal models of allergic contact dermatitis and does not induce skin atrophy. Topical application of SDZ ASM 981 has been shown to be effective in atopic dermatitis (AD) and allergic contact dermatitis. Clinical studies using semi-occlusive conditions have also shown effectiveness in psoriasis. SDZ ASM 981 holds promise in overcoming the drawbacks of topical corticosteroids and studies are ongoing to further investigate its efficacy and safety in the treatment of inflammatory skin diseases.

p53-dependent DNA repair and apoptosis respond differently to high- and low-dose ultraviolet radiation

p53 plays an essential part in the maintenance of the cellular genetic stability after a DNA-damaging event such as ultraviolet (UV) radiation. Following UV radiation, the amount of p53 protein is elevated. The increased p53 is believed to induce cell cycle arrest, promote nucleotide excision repair (NER) and apoptosis. To study if cells respond differently to high- and low-dose UV radiation, we examined the DNA repair efficiency and apoptosis rate of human and murine fibroblasts after UV radiation. Using a host cell reactivation assay, we found that NER was increased after low doses but not after high doses of UV radiation. In contrast, apoptosis occurred only after the cells received high doses (over 200 J/m2), but not low doses of UVB. The induction of both NER and apoptosis was observed only in p53+/+ murine fibroblasts, not in p53-/- cells, indicating that both stress response mechanisms are dependent on wild-type p53 function. UV radiation induced the expression of p53 protein in a dose-dependent manner up to 400 J/m2. In contrast, p21waf1/cip1 was induced only after low doses and bax only after high doses of UV radiation, supporting the roles of p21waf1/cip1 and bax in NER and apoptosis, respectively. Taken together, these results indicate that cellular stress response to UV radiation depends on UV dose, DNA repair after low doses and apoptosis after high doses, and that both mechanisms are dependent on wild-type p53 function.

Expression of apoptosis regulators in cutaneous malignant melanoma

Metastatic malignant melanoma (MM) is usually incurable and responds poorly to chemotherapy. Because many cytotoxic drugs cause cell death by inducing apoptosis, an imbalance of apoptosis regulatory proteins may contribute to MM treatment resistance. We have previously shown reduced expression of Bcl-2 protein, a negative regulator of apoptosis, in MM as compared with benign nevi. It is hypothesized that other apoptosis regulators may be involved in survival of MM cells. We examined the expression of Bax, Bcl-2, Bcl-X, and Mcl-1 in human benign nevi, primary MM, and metastatic MM using immunohistochemistry. Results were confirmed with Western blotting. The proapoptotic protein, Bax, was surprisingly overexpressed in all MM samples compared with benign nevi. Interestingly, in most MM samples there was overexpression of Mcl-1 or Bcl-XL, both negative regulators of apoptosis. Increased expression of Mcl-1 and Bcl-XL was first observed in thin primary melanomas, suggesting that up-regulation of these proteins represents a relatively early event associated with malignant transformation in MM. As published previously, the majority of primary and metastatic MM exhibited reduced Bcl-2 levels. We conclude that the apoptosis inhibitors Bcl-XL or Mcl-1, alone or in combination, may circumvent the normal cell death pathway, contributing to the pathogenesis and treatment resistance in metastatic MM.

p53-regulated apoptosis is differentiation dependent in ultraviolet B-irradiated mouse keratinocytes

Previous studies from our laboratory, using p53 transgenic mice, have suggested that ultraviolet (UV) light-induced keratinocyte apoptosis in the skin is not affected by overexpression of mutant p53 protein. To further elucidate a possible role for p53 in UV-induced keratinocyte cell death, we now examine apoptosis in skin and isolated keratinocytes from p53 null (-/-) mice and assess the influence of cell differentiation on this process. In vivo, using this knockout model, epidermal keratinocytes in p53-/- mice exhibited only a 5.2-fold increase in apoptosis after 2000 J/m2 UVB irradiation compared with a 26.3-fold increase in normal control animals. If this p53-dependent apoptosis is important in elimination of precancerous, UV-damaged keratinocytes, then it should be active in the undifferentiated cells of the epidermal basal layer. To test this hypothesis, we examined the effect of differentiation on UV-induced apoptosis in primary cultures of murine and human keratinocytes. Apoptosis was p53-independent in undifferentiated murine keratinocytes, which exhibited relative resistance to UVB-induced killing with only a 1.5-fold increase in apoptosis in p53+/+ cells and a 1.4-fold increase in p53-/- cells. Differentiated keratinocytes, in contrast, showed a 9.4-fold UVB induction of apoptosis in p53+/+ cells, almost three times the induction observed in p53-/- cells. This UV-induced difference in apoptosis was observed when keratinocytes were cultured on type IV collagen substrate, but not on plastic alone. Western blotting of UV-irradiated, differentiated keratinocytes did not support a role for either Bax or Bcl-2 in this process. In support of these findings in mice, cell death in human cultured keratinocytes also occurred in a differentiation-associated fashion. We conclude that p53-induced apoptosis eliminates damaged keratinocytes in the differentiated cell compartment, but this mechanism is not active in the basal, undifferentiated cells and is therefore of questionable significance in protection against skin cancer induction.

p53-dependent regulation of nucleotide excision repair in murine epidermis in vivo

BACKGROUND

p53 protects the integrity of the genome by inducing programed cell death or by promoting DNA repair. We have previously shown that loss or mutation of p53 leads to reduced DNA repair in keratinocytes.

OBJECTIVE

The hypothesis that p53 regulates repair of ultraviolet light-induced epidermal DNA damage in vivo was tested in mice.

METHODS

An immunohistochemical assay for pyrimidine dimers and 6-4 photoproducts was performed on ultraviolet-irradiated skin from p53 null (-/-) and wild type (+/+) mice. Immunostaining for photoproducts was quantified using computer-assisted imaging. The level of DNA repair was then expressed as the percentage of positive cells remaining as compared to the zero hour time point.

RESULTS

p53+/+ mouse skin exposed to 1000 J/m2 retained ' 25% of epidermal cyclobutane dimers at 48 h, whereas approximately 50% remained in p53-/- cells. Using the same UV dose, p53+/+ mice retained 20% of detectable 6-4 photoproducts by 24 h, whereas about 50% remained in epidermal cells of p53-deficient mice.

CONCLUSION

Using in situ labelling of UV-damaged cells, we confirm our earlier conclusion that p53 regulates DNA repair within the epidermis after exposure to UV light.

Immunosuppressive agents in dermatology. An update

Azathioprine, cyclophosphamide, methotrexate, and cyclosporine are the immunosuppressive agents most commonly used by dermatologists. Azathioprine has a relatively good safety profile and is therefore often preferred for the treatment of chronic eczematous dermatitides and bullous disorders. Awareness of the role of genetic polymorphisms in its metabolism can increase the efficacy and safety of this drug. Cyclophosphamide is an antimetabolite that has a more rapid onset of immunosuppressive effect than azathioprine, but has significant short-term and long-term toxicity. It is of use in fulminant, life-threatening cutaneous disease. Methotrexate is an antimetabolite that has significant anti-inflammatory activity. Despite its hepatotoxicity, its role in inflammatory dermatoses is broadening. Likewise, the role of cyclosporine is being expanded. This drug has potent T-cell inhibitory effects secondary to interference with intracellular signal transduction. Given the evidence for cumulative renal toxicity, it currently has a role in the short-term treatment of refractory psoriasis and atopic dermatitis, as well as in select inflammatory dermatoses. Familiarity with disease-specific clinical efficacy, side-effect profile, and dosage allows the successful and judicious use of these drugs in dermatologic disorders.

Differentiation-dependent p53 regulation of nucleotide excision repair in keratinocytes

The role of the tumor suppressor p53 in repair of ultraviolet light (UV)-induced DNA damage was evaluated using a host-cell reactivation (HCR) assay. HCR determines a cell's ability to repair UV-damaged DNA through reactivation of a transfected CAT reported plasmid. Most UV damage is removed through nucleotide excision repair (NER). Primary murine keratinocytes isolated from p53-deficient and wild-type p53 mice were used in the HCR assay. The NER was reduced in p53-/- keratinocytes as compared with p53+/+ keratinocytes. The reduced DNA repair in p53-/- mice was confirmed with a radioimmunoassay comparing cyclobutane dimers (CPDs) and (6-4) photoproducts in p53+/+ and p53-/- keratinocytes after the cells were exposed to UV irradiation. Our results demonstrate that wildtype p53 plays a significant role in regulating NER. Furthermore, as there is evidence that p53 protein levels decrease after keratinocytes become differentiated, we sought to determine whether p53 plays a role in NER in differentiated keratinocytes. Differentiation of the keratinocytes by increasing the Ca2+ concentration in the culture media resulted in a marked reduction in NER equally in both p53+/+ and p53-/- groups. This finding suggests that reduced DNA repair after differentiation is p53 independent. A similar reduction in HCR was confirmed in differentiated human keratinocytes. These data, taken together, indicate that p53 or p53-regulated proteins enhance NER in basal undifferentiated keratinocytes but not in differentiated cells. As nonmelanoma skin cancers originate from the basal keratinocytes, our findings suggest that loss of p53 may contribute to the pathogenesis of this common skin cancer.

Treatment of pyoderma gangrenosum

Critical to the proper management of pyoderma gangrenosum are correct diagnosis, identification and treatment of any underlying disorder, and the proper choice of topical and systemic therapy. Many agents are available for the treatment of pyoderma gangrenosum. We review the current therapeutic options, their efficacy and side effects, and we offer some guidelines for their proper selection.

Decreased DNA repair but normal apoptosis in ultraviolet-irradiated skin of p53-transgenic mice

p53 tumor suppressor plays a vital role in the cellular responses to genotoxic stress. It is believed that p53 regulates the cell cycle by activating the G1 checkpoint after exposure to agents like ionizing radiation, ultraviolet (UV) radiation, or genotoxic chemicals. Recently, it is conjectured that p53 may have additional functions in DNA repair and apoptosis. Previously, we demonstrated that p53-transgenic mice that carry mutant alleles of a p53 gene developed twice as many skin tumors as control mice after UV exposure. To elucidate the molecular mechanisms of mutant p53 in skin cancers, we studied DNA repair efficiency and the rate of apoptosis in murine keratinocytes after UV irradiation. In this report, we show that mutant p53-transgenic mouse skin has reduced repair of UV-induced DNA damage in both in vivo and in vitro radioimmunoassays. In control mice, DNA repair is associated with increased amounts of wild-type P53 protein. Unexpectedly, mutant p53-transgenic mice had slightly increased apoptosis after UV irradiation, suggesting that the wild-type p53 protein in the cells still functions in inducing apoptosis, or that this cell death results from p53-independent mechanisms. These results suggest that mutant p53 interferes with wild-type p53 in the repair of UV-induced DNA damage but not in apoptosis.

Graft-versus-host reaction affecting lesional skin but not normal skin in a patient with piebaldism

A case of graft-vs.-host disease (GVHD) arising solely within an area affected by piebaldism is described. The patient, a 35-year-old woman with a single hypopigmented patch on the right leg present since birth, had received an allogeneic bone marrow transplant (BMT) from an HLA-identical sibling donor, for treatment of a myelodysplastic syndrome (MDS). Beginning on day +38 post-BMT, the patch developed changes which were histologically consistent with GVHD. Syngeneic mixed epidermal cell-lymphocyte reaction (MECLR) testing of tissue from the patch, and from adjacent normal skin, showed differences which suggest that piebaldism-affected skin is immunologically different from normal skin. These findings may offer new insight into the pathophysiology of this disorder.

Ultraviolet radiation induction of squamous cell carcinomas in p53 transgenic mice

Mutations of the p53 gene have been implicated in the pathogenesis of cutaneous squamous cell carcinoma (SCC). To examine the role of p53 in skin carcinogenesis, we observed the development of skin cancers in p53 transgenic mice which carry multiple copies of a mutant allele of the p53 gene with or without chronic UVB radiation. Thirty-one tumors developed in 19 UV-irradiated p53 transgenic mice versus 14 of 19 in the control group; 9 p53 transgenic mice but none of the control mice developed multiple tumors. Histologically. 14 of 14 tumors in the CD-1 mice were SCCs. In the p53 transgenic mice, 25 of 31 tumors were SCCs, and 6 were benign tumors. The mean time to appearance of tumors did not differ between CD-1 mice (26.3 weeks) and the p53 transgenic mice (25.7 weeks; P = 0.512). The p53 protein, which was undetectable by immunohistochemistry in the keratinocytes of CD-1 mice, was elevated in 93% (13 of 14) of tumors from CD-1 mice. These data indicate that mutation of the p53 gene is an important step in the development of SCC. p53 mutations do not alter the latent period of UV-induced SCC but significantly increase the number of tumors and the propensity for multiple tumor development.

Immunohistochemical analysis of Bcl-2 protein regulation in cutaneous melanoma

Cutaneous melanoma is becoming increasingly common. Genetic and environmental factors are thought to play a role in its pathogenesis. We have previously shown that normal human melanocytes strongly express the oncoprotein, Bcl-2. To determine the role of Bcl-2 in melanocytic tumors, we studied human benign nevi and melanomas for expression of Bcl-2 protein using immunohistochemistry. Our results show that benign melanocytes from 3 of 4 normal skin biopsies and 5 of 7 common acquired nevi strongly express Bcl-2. Conversely, only 3 of 23 primary cutaneous melanomas and 3 of 9 metastatic melanomas showed strong staining in comparison with melanocytes from normal skin and common acquired nevi (chi 2, P = 0.0021). Interestingly, 0 of 6 dysplastic nevi, a precursor of melanoma, demonstrated strong staining as compared with melanocytes and nevi (8 of 11; chi 2, P = 0.02), but similar expression to that of melanoma (6 of 32; chi 2, P = 0.6). We conclude that Bcl-2 expression decreases in malignant melanoma and suggest that this may be related to the autonomous growth characteristics of malignant melanoma.

Pooled analysis of the efficacy of bacille Calmette-Guerin (BCG) immunotherapy in malignant melanoma

BACKGROUND

The trials of bacille Calmette-Guerin (BCG) as adjuvant therapy in malignant melanoma conducted over the preceding 2 decades have presented conflicting claims of efficacy.

OBJECTIVE

Determination of the role of BCG immunotherapy in malignant melanoma.

METHODS

Critical analysis of randomized clinical trials of stage I and II melanoma and all reported trials of intralesional and oral BCG in stage III melanoma was conducted. A literature search used the Medline data base (1966-1992);bibliographic reviews of relevant texts and pertinent articles.

RESULTS

No significant benefit of BCG as postsurgical adjuvant therapy in stage I malignant melanoma was observed. Although two of seven trials in stage II melanoma demonstrated benefit with the addition of BCG, the trial with the greatest power in this series detected no difference in outcomes. In stage III malignant melanoma, there was no significant benefit with addition of BCG to various chemotherapeutic regimens. Oral BCG monotherapy produced complete responses in 6%, partial responses in 1%, and extended survival in 7% of patients. Objective responses were observed primarily in patients with intracutaneous non-visceral metastases. Pooled analysis of 15 non-controlled trials of intralesional BCG injections revealed complete responses in 19%, partial responses in 26%, and extended survival in 13% of patients with stage III melanoma. Objective responses to intralesional BCG were more likely in patients with solely cutaneous metastases, particularly intradermal lesions.

CONCLUSION

Pooled analysis of non-placebo controlled trials of intralesional BCG for stage III malignant melanoma supports a trend to enhanced survival in patients with cutaneous non-visceral metastases.

A putative marker for human melanoma. A monoclonal antibody derived from the melanoma gene in the Xiphophorus melanoma model

A MoAb was raised against a peptide corresponding to an exposed domain of the putative tyrosine kinase receptor protein encoded by Xmrk, a gene involved in melanoma formation and/or progression in the Xiphophorus fish melanoma model. The antibody reacts specifically with cells from human melanocytic lesions, ie, common acquired nevi, primary and metastatic melanoma biopsies. No reactivity with other cells, including normal melanocytes, was observed in the biopsies or with cells in biopsies from normal tissue (skin, liver, lung, spleen) and from other malignancies including those of neuroectodermal origin. The reactivity was very weak and variable in metastatic melanomas but very strong and characteristic of a receptor-type antigen in primary melanomas, a stage in melanoma progression in which cells have acquired metastasizing potential. It is suggested that the antigen recognized may be involved in growth promotion and represents the human equivalent of the fish melanoma gene product.

Leukemic T cells from patients with cutaneous T-cell lymphoma demonstrate enhanced activation through CDw60, CD2, and CD28 relative to activation through the T-cell antigen receptor complex

Antigen-dependent activation of T cells occurs through the T-cell antigen-receptor complex (TCR/CD3). Antigen-independent T-cell activation may occur through the surface molecules CDw60, CD2, and CD28. We wished to determine whether these antigen-independent T-cell-activation pathways could be involved in proliferation of leukemic T cells from patients with cutaneous T-cell lymphoma (CTCL). Whereas CDw60 was only expressed on 28% +/- 7% (mean +/- SEM) of blood T cells obtained from healthy control subjects (n = 4), CDw60 was expressed on 94% +/- 3% of blood T cells obtained from patients with CTCL (n = 4). Dual color immunofluorescence microscopy of the T-cell infiltrate in involved skin of these patients demonstrated that almost 100% of the T cells expressed CDw60. Not only did T cells in the patients with CTCL express CDw60, but triggering of the T cells with anti-CDw60 resulted in enhanced proliferation relative to anti-TCR/CD3 and mitogenic lectins. Other antigen-independent pathways also appeared highly active in the T cells from patients with CTCL because enhanced proliferation relative to anti-TCR/CD3 or mitogenic lectins was found when anti-CD2 or anti-CD28 plus phorbol ester was used as stimulant. Despite the brisk proliferation induced by anti-CDw60, anti-CD2, or anti-CD28, T cells from the patients did not produce detectable amounts of gamma-interferon. The inability to produce gamma-interferon correlates with our finding of absent (n = 3) or weak (n = 1) intercellular adhesion molecule-1 expression in the lesional keratinocytes in these patients. In conclusion, T cells of patients with CTCL demonstrate elevated expression of a T-cell-independent signaling molecule CDw60 and respond to antigen-independent activating signals.

Immunosuppressive agents in dermatology

Azathioprine, cyclophosphamide, and cyclosporine are immunosuppressive agents commonly used by dermatologists. Azathioprine has a good safety profile and is preferred by most dermatologists for the treatment of bullous pemphigoid, cutaneous vasculitides, chronic eczematous dermatitides, and cutaneous manifestations of connective tissue diseases. For more fulminant diseases such as Wegener's granulomatosis, lymphomatoid granulomatosis, severe cases of systemic lupus erythematosus, or pemphigus, cyclophosphamide is more effective and its use is justified even though it is more toxic. Cyclosporine has been shown to be effective in a variety of dermatoses; the most promising results are seen in psoriasis, lichen planus, pyoderma gangrenosum, and chronic eczematous dermatitides. The long-term safety of cyclosporine remains to be determined, and it should be used judiciously with careful evaluation of the risk-benefit ratio in each case. Dermatologists who use immunosuppressive agents should be familiar with their indications, side effects, dosage, and monitoring.

Common Skin Cancers: How to diagnose and treat them

Melanoma, basal cell carcinoma, and squamous cell carcinoma are the three most common forms of skin cancer. The incidence of skin cancer is increasing at an alarming rate. Early detection is the key to successful management. In this article, the salient clinical features and diagnostic clues for these tumors and their precursor lesions are presented. Current management guidelines are also discussed.

Cutaneous manifestations of gastrointestinal disorders. Part II

The cutaneous manifestations of inflammatory bowel disorders, vascular disorders of the gastrointestinal tract, celiac disease, and bowel-associated dermatosis-arthritis syndrome are reviewed. The significance of these signs, guidelines for their management, and investigations are discussed.

T-cell receptor variable region gene expression in cutaneous T-cell lymphomas

The cutaneous T-cell lymphomas (CTCL) are a group of diseases characterized by malignant proliferations of CD4 positive T-cells having monoclonally rearranged T-cell receptor (TCR) genes. A recent study using monoclonal antibodies to two TCR beta-chain variable (V) region gene products showed preferential expression of the V beta 8 gene product in these tumors. The finding of predominant usage of a single V beta gene would imply that selection by antigen is important in the etiology of these tumors. We have studied eight cases of cutaneous T-cell lymphoma and one cell line derived from a patient with mycosis fungoides/Sezary syndrome, using an extended panel of antibodies to V region gene products. Contrary to the previous report, in our study expression of the V beta 8 gene product by tumor cells was not observed in any of the cases of CTCL or in the tumor cell line studied; preferential use of any of the variable region genes recognized by the antibodies in the panel was not observed.

Cutaneous manifestations of gastrointestinal disorders. Part I

This article reviews the cutaneous manifestations of gastrointestinal tract diseases. In part I, the gastrointestinal tract polyposis syndromes and gastrointestinal tract malignancies will be discussed. The cutaneous manifestations of inflammatory bowel disorders, vascular disorders of the gastrointestinal tract, celiac disease and bowel-associated dermatosis-arthritis syndrome will be discussed in part II. For each entity, a brief summary of the gastrointestinal tract (and other extracutaneous) manifestations is given. This is followed by a detailed discussion of the cutaneous signs. Current guidelines for the investigation and management of these diseases are presented.

Cyclosporine in nonpsoriatic dermatoses

This article reviews the indications, efficacy, and possible mechanisms of action of cyclosporine in the treatment of nonpsoriatic dermatoses. These dermatoses can be categorized according to their responsiveness to cyclosporine therapy as excellent, moderate, variable, and nonresponsive. The advantages and disadvantages of cyclosporine are discussed and guidelines are proposed for its use in nonpsoriatic dermatoses.

Genotypic analysis of T-cell clones derived from cutaneous T-cell lymphoma lesions demonstrates selective growth of tumor-infiltrating lymphocytes

The nature of T cells contained within cutaneous lesions of cutaneous T-cell lymphoma (CTCL) has not been studied at the clonal level. T cells extracted from skin lesions of two CTCL patients were cloned by limiting dilution and propagated in interleukin-2 (IL-2) containing medium with periodic lectin stimulation. Twelve T-cell clones were derived from each patient. In both cases, genotypic analysis of the T-cell clones revealed that these clones had T-cell receptor (TCR) beta- and gamma-chain gene rearrangements distinct from the predominant, presumably malignant, clone present in the skin, lymph nodes, or blood. This suggests that they were derived from presumably reactive (non-malignant) T cells. Furthermore, these clones had gene rearrangements different from each other, indicating their multiple clonal origins. The failure to propagate in vitro the CTCL T-cell clone suggests that CTCL cells may have growth requirements different from normal T cells. Thus, conventional T-cell culturing methods using IL-2 and lectins as mitogen may selectively propagate the presumably reactive T cells contained within the skin lesions. The ability to selectively grow these reactive lesional T cells (so-called tumor infiltrating lymphocytes) raises the possibility that these cells could be used in adoptive immunotherapy.

Pigmented streaks in melanoma scars

Fifty consecutive patients from our melanoma clinic were examined for the presence of transverse pigmented streaks in their melanoma surgical scars. Thirty-four (68%) patients were noted to have pigmented streaks in their melanoma scars. Ten of these 34 patients also had similar pigmented streaks in their nonmelanoma surgical scars. Long-term follow-up (mean 81.7 +/- 14.5 months, minimum 36 months) of these patients with the melanoma-scar pigmented streaks indicates that the streaks are benign. Histologic examination of a representative pigmented streak revealed basal layer hyperpigmentation without melanocytic hyperplasia. These streaks are frequently associated with the presence of freckles. However, this association may simply be coincidental.

Oral cyclosporine in the treatment of inflammatory and noninflammatory dermatoses. A clinical and immunopathologic analysis

Cyclosporine is known to be effective in the treatment of psoriasis. In this study, we have used oral cyclosporine (6 mg/kg per day) given for 5 to 30 weeks to 24 patients for the treatment of 12 different dermatoses. Patients with the following diseases demonstrated a marked response or total clearing: 1 patient each with pyoderma gangrenosum, pityriasis lichenoides chronica, and psoriasis of the acrodermatitis continua of Hallopeau type. Moderate to marked response occurred in both patients with epidermolysis bullosa acquisita and the patient with hidradenitis suppurativa. Minimal to moderate responses were obtained in both patients with granuloma annulare, 1 of 2 with acrodermatitis continua of Hallopeau, both patients with Darier's disease, and 1 of 6 patients with vitiligo. Little or no response was noted in both patients with sarcoidosis, all 3 patients with pityriasis rubra pilaris, 5 of 6 patients with vitiligo, 1 patient with pemphigus foliaceous, and 1 with pemphigus vulgaris. Clinical side effects were mild and transient and included dysesthesia, fatigue, hypertrichosis, nausea, and flushing. The most frequent clinically significant abnormalities were hypertension and renal dysfunction, with all factors normalizing within 1 month of discontinuation of cyclosporine therapy.

T cell receptor beta-chain gene rearrangement without gamma-chain gene rearrangement in cutaneous T cell lymphoma: an unusual finding

T cells from the blood and skin of a patient with cutaneous T cell lymphoma demonstrated rearrangement of the T cell receptor beta-chain gene in the absence of rearrangement of the gamma-chain gene. To our knowledge, this has not been previously reported. This finding was unexpected in light of prevailing concepts of T cell ontogeny. Potential explanations for it are discussed.

Therapy for cutaneous melanoma: an update

This article reviews the current therapy for cutaneous melanoma. Diagnosis, staging, and prognostic evaluation, which are crucial to proper management, are discussed. Surgical excision is the treatment of choice for primary melanoma. The resection margins should be tailored to tumor thickness. Guidelines for surgery are presented. The controversy about elective regional lymph node dissections is discussed. Limb perfusion, chemotherapy, immunotherapy, radiotherapy, and hormonal therapy as adjuvant treatments of primary melanomas as well as the treatment of disseminated melanomas are reviewed and new developments are highlighted. Guidelines for the management of metastatic melanoma at various sites are given. Special issues such as "pregnancy/estrogen and melanoma" and "borderline melanoma" are discussed and approaches to these problems are suggested. Recommendations are given for the follow-up and counseling of patients with melanoma.

Oral cyclosporine for the treatment of alopecia areata. A clinical and immunohistochemical analysis

Cyclosporine inhibits the activation of helper T cells that may be pathogenic in alopecia areata. Therefore we treated six patients with alopecia areata (five men, one woman) with oral cyclosporine, 6 mg/kg/day for 12 weeks. Three patients had alopecia universalis, one had alopecia totalis, and two had patchy alopecia areata of the scalp. Hair regrowth in the scalp of all patients occurred within the second and fourth weeks of therapy, followed by hair regrowth of the face and chest (in the male patients), pubic area, extremities, and axillae. Overall, the site of best response was the scalp. Cosmetically acceptable terminal hair regrowth on the scalp occurred in three of six patients. Significant hair loss, however, occurred in all patients within 3 months of discontinuation of cyclosporine treatment. Clinical response correlated with changes in immune cell infiltration of the hair follicles. The number of leukocytes per hair follicle was quantified in transverse scalp biopsy sections stained with a panel of monoclonal antibodies. The degree of terminal hair regrowth correlated significantly with decreases in follicular epithelial human lymphocyte antigen-DR and intercellular adhesion molecule-1 expression, T cells, helper/inducer (CD4) T cells, suppressor/cytotoxic (CD8) T cells and Langerhans cells (CD1+DR+) from the hair follicles during cyclosporine therapy. A significant decrease in the CD4/CD8 ratio occurred early in the course of treatment and was maintained throughout the therapy. This decrease suggests that cyclosporine not only cleared immune cells from the hair follicles but also altered the balance of regulatory lymphocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Intralesional cyclosporine in the treatment of psoriasis. A clinical, immunologic, and pharmacokinetic study

In a double-blind, vehicle-controlled study, all of six psoriatic plaques treated with intralesional cyclosporine administered three times weekly for 4 weeks showed complete clearing or incomplete but significant clearing in comparison with vehicle-treated plaques (p less than 0.01). Epidermal thickness decreased from 0.42 +/- 0.07 to 0.27 +/- 0.08 mm at 4 weeks (p less than 0.03). Biopsy specimens obtained on day 5, before any clinical improvement, revealed a significant reduction of epidermal DR+CD1- antigen-presenting cells, epidermal and dermal monocytes, and keratinocyte intercellular adhesion molecule-1 expression. By day 5 the stratum corneum reverted to normal in the plaques receiving cyclosporine. Pain at the injection site was the major side effect. Steady-state blood cyclosporine levels ranged from 20 to 30 ng/ml during the first 12 hours after injection and became undetectable at 48 hours. These data suggest that cyclosporine improves the skin of patients with psoriasis by a local mechanism of action.

Treatment of severe lichen planus with cyclosporine

Two patients with severe chronic lichen planus were successfully treated with oral cyclosporine (6 mg/kg/day). A response was noted within 4 weeks, and complete clearing was achieved after 8 weeks of treatment. No significant adverse effect was noted. The patients have remained in remission 3 and 10 months after therapy, respectively. Clinical improvement was accompanied by significant reduction in the T cell infiltrate in the skin. Abnormal expression of keratinocyte intercellular adhesion molecule-1 (ICAM-1), which was present before therapy, became undetectable after 1 week of cyclosporine therapy, before any significant clinical and histologic change.

Cyclosporine in the treatment of psoriatic arthritis

The short-term efficacy of cyclosporine in the treatment of six patients with moderately severe to severe psoriatic arthritis was evaluated in an open study. Patients received oral cyclosporine (6 mg/kg/d) for eight weeks. In all patients, significant improvement of psoriasis was noted within two to four weeks. At the end of therapy, rheumatologic assessment revealed the following trends in disease activity: a decrease in the number of tender joints, joint tenderness index, duration of morning stiffness, and an increase in grip strength. There was a decrease in the number of swollen joints, joint swelling index, and the time taken to walk 50 ft. Overall disease activity significantly improved as assessed independently by the patient and physician. For psoriasis and psoriatic arthritis, disease activity worsened toward baseline within four weeks of discontinuation of therapy. Short-term, low-dose cyclosporine therapy may be effective in treating psoriasis and psoriatic arthritis.

Measurement of epidermal thickness in normal skin and psoriasis with high-frequency ultrasound

In this study, we employed a high-frequency ultrasound system to measure the epidermal thicknesses of psoriasis plaques and normal skin in vivo. Eighty-four percent of the ultrasound measurements fell within the range of epidermal thickness determined by histology. The average thickness of untreated psoriasis measured by ultrasound was significantly greater than that of either treated psoriasis or normal skin. Ultrasound measurement of thickness was consistent with clinical assessment. Ultrasound measurements also demonstrated known variations in epidermal thickness by body site. Further development is needed to obtain measurements that are fully representative of the epidermis.

Nickel dermatitis in infants

8 cases of allergic contact dermatitis to nickel in infants are reported. All showed a papular dermatitis matching the sites of contact. Patch testing was performed on 3 patients, 2 were tested to nickel sulfate in pet. at concentrations of 1.0%, 1.5%, 2.0%. 1 was tested to 2.5% alone. All developed ++ reactions at each concentration tested. We observed a strong association of nickel dermatitis with atopy; 7 of 8 patients had a family history of atopy and 5 of 8 had features of coexistent atopic dermatitis. The relationship between atopy and allergic contact dermatitis is briefly reviewed. Nickel dermatitis may aggravate atopic dermatitis; avoidance of metal contact is crucial in the management of these patients.