A randomized controlled trial of pimecrolimus cream 1% in adolescents and adults with head and neck atopic dermatitis and intolerant of, or dependent on, topical corticosteroids.

BACKGROUND: There is a need for alternative treatments for atopic dermatitis (AD) of the face and neck as long-term use of topical corticosteroids (TCS) is associated with skin atrophy and telangiectasia and some patients develop allergy, intolerance or other side-effects. OBJECTIVES: This study was designed to assess the efficacy and safety of pimecrolimus cream 1% in patients with AD of the face and neck who are either dependent on, or intolerant of, TCS. METHODS: A 12-week study comprising a 6-week, double-blind, randomized, vehicle-controlled phase was conducted, followed by a 6-week, open-label phase. Two hundred patients aged 12 years or over with mild to moderate head and neck AD, intolerant of, or dependent on, TCS were randomized to either pimecrolimus cream or vehicle cream. The primary efficacy criterion was the facial investigator's global assessment score at 6 weeks. Secondary efficacy criteria were head and neck Eczema Area and Severity Index (EASI), pruritus score and eyelid dermatitis. Facial skin atrophy and telangiectasia were assessed with dermatoscopy. RESULTS: A significantly higher percentage of patients treated with pimecrolimus was cleared or almost cleared of facial AD compared with vehicle (47% vs. 16%, respectively). A statistically significant difference was also seen on head and neck EASI and pruritus score. Significantly more pimecrolimus-treated patients than vehicle-treated patients achieved clearance of eyelid dermatitis (45% vs. 19%, respectively). Among the 77 patients with skin atrophy at baseline, treatment with pimecrolimus was associated with a reversal in skin thinning. Of the 112 patients with telangiectasia at baseline, no statistically significant difference was seen between treatment groups. Adverse events occurred with similar frequency in both groups. CONCLUSION: Pimecrolimus cream 1% is effective in patients with head and neck dermatitis intolerant of, or dependent on, TCS. Reversion of skin atrophy may occur during TCS-free intervals.

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.

Preoperative ketorolac has a preemptive effect for postoperative third molar surgical pain.

There is uncertainty regarding the role of preemptive analgesia in preventing postoperative pain. Most previous studies were of parallel design completed under general anesthesia with many confounding inter-patient's variables. The present study evaluated the efficacy of preemptive ketorolac in a crossover design in patients undergoing bilateral mandibular third molar surgery. This was a double blind, randomized, placebo-controlled study where 34 patients had each of their identical impacted mandibular third molars removed under local anesthesia on two occasions. Each patients acted as their own control; one side was pretreated with intravenous ketorolac 30 mg before surgery followed by placebo injection after surgery, and for the other side, the patient was given placebo injection before surgery and post-treated with intravenous ketorolac 30 mg after surgery. The difference in postoperative pain between pretreated and post-treated side in each patient was assessed by four primary end-points: pain intensity as measured by a 100-mm visual analogue scale hourly for 12 h, time to rescue analgesic, postoperative analgesic consumption, and patient's global assessment. Throughout the 12-h investigation period, patients reported significantly lower pain intensity scores in the ketorolac pretreated sides when compared with the post-treated sides (P = 0.003). Patients also reported a significantly longer time to rescue analgesic (8.9 h versus 6.9 h, P = 0.005), lesser postoperative analgesic consumption (P = 0.007) and better global assessment for the ketorolac pretreated sides (P = 0.01). Pretreatment with intravenous ketorolac has a preemptive effect for postoperative third molar surgery and extended the analgesia by approximately 2 h.

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.

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.

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 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.

Temporomandibular disorders--an overview.

Temporomandibular disorders (TMD) have been an area of increased clinical and scientific inquiry in dentistry. This is due to increased patient awareness and desire for treatment as well as scientific advances in the fields of epidemiology, neurobiology and diagnostic imaging. This article sets out to introduce this disorder and describes its aetiology and management.

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.

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.

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-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.