Downregulation of the inhibitor of apoptosis protein survivin in keratinocytes and endothelial cells in psoriasis skin following infliximab therapy

BACKGROUND: Survivin, an inhibitor of apoptosis protein (IAP), has been implicated in endothelial cell stability, through inhibition of apoptosis and in cell proliferation. OBJECTIVES: To evaluate the effect of antitumour necrosis factor (TNF)-alpha therapy on survivin expression in psoriasis skin at 0, 2 and 12 weeks after infliximab therapy. METHODS: Skin biopsies were obtained from 16 patients; 11 also had arthritis with active skin/joint disease. Clinical scores [Psoriasis Area and Severity Index (PASI), involved body surface area (BSA), Disease Activity Score (DAS28) and Health Assessment Questionnaire] were recorded. Inflammatory infiltration and survivin protein expression were examined and graded by immunohistochemical staining, and mRNA levels were determined by real-time polymerase chain reaction. RESULTS: Survivin mRNA and protein were demonstrated in all baseline lesional biopsies. Survivin mRNA and protein expression was significantly greater in lesional compared with nonlesional baseline skin (P < 0.05). Differential cellular localization of survivin was demonstrated with cytoplasmic survivin protein expression localized to the perivascular/endothelial regions and strong nuclear staining localized in the basal layer of the epidermis. Infliximab produced a dramatic clinical response in skin and joints (P < 0.05), paralleled by significant reduction in the inflammatory infiltrate and survivin protein expression (P < 0.05) which was reflected at the mRNA level where expression was significantly reduced by week 12 (P < 0.01). Survivin protein levels before and after treatment significantly correlated with PASI (r = 0.478, P < 0.05) and BSA scores (r = 0.528, P < 0.024). PASI strongly correlated with BSA (r = 0.949, P < 0.0001) and DAS28 (r = 0.717, P < 0.002) scores. CONCLUSIONS: Survivin correlates with disease activity in patients with psoriasis and is significantly downregulated following anti-TNF-alpha treatment. Understanding the role of IAPs in cell survival/antiapoptosis and proliferation mechanisms may provide important insights into downstream therapeutic targeting in inflammation.     

银屑病与调节性细胞死亡关系研究进展

银屑病是一种慢性炎症性皮肤病,研究显示银屑病皮损中存在多种调节性细胞死亡方式。不同的细胞死亡方式发生机制不同且对银屑病影响各异,细胞凋亡异常参与银屑病表皮角化不全,而坏死性凋亡等细胞死亡方式则影响银屑病的炎症状态。本文对不同的调节性细胞死亡方式与银屑病之间关系的研究进展作一综述。     

Expression of wild-type, but not mutant, loricrin causes programmed cell death in HaCaT keratinocytes

The epidermal cornified cell envelope is a complex protein-lipid composite that replaces the plasma membrane of corneocytes and is crucial for epidermal barrier function. Loricrin is a major constituent of the epidermal cornified cell envelope, contributing approximately 70% by mass. In order to explore novel function of wild-type (WT) loricrin other than the major component of the epidermal cornified cell envelope, we transiently expressed construct encoding human WT and mutant loricrin (730insG) in HaCaT keratinocytes. HaCaT cells transfected with WT or mutant loricrin were at differentiation level. WT loricrin in the transfected cells was seen diffusely in the cytoplasm and nuclei. Positive transferase deoxytidyl uridine end labeling staining was observed in the nuclei of WT loricrin-transfected HaCaT keratinocytes. Data from the DNA fragmentation assay showed that only WT loricrin induced DNA ladders compared with that of mutant loricrin. WT loricrin-transfected HaCaT keratinocytes were susceptible to programmed cell death (PCD). Activation of caspase-14 was also seen. In contrast, PCD or activation of caspase-14 did not occur in mutant loricrin-transfected HaCaT cells. These results suggest that the expression of WT loricrin facilitates induction of PCD in HaCaT keratinocytes.     

银屑病患者淋巴细胞与角质形成细胞体外培养NF-κB的表达

目的：探讨银屑病发病中淋巴细胞和角质形成细胞的相互作用及核因子调控机制。方法：从银屑病患者外周血分离单一核细胞（PBMC）．正常人皮肤体外培养获角质形成细胞（KC），两者混合培养，利用流式细胞仪分析培养体系及PBMC、KC各自的转录因子NF-κB表达，ELISA法测上清液中IL-8、ICAM—I含量。结果：银屑病患者培养体系及PBMC、KC中NF—κB和细胞因子的表达水平均高于健康对照组（P〈0．01）。结论：银屑病患者中NF—κB的活化增强是其发病的重要因素，同时提示抑制NF—κB活性的药物可能有助于银屑病的治疗。     

A dramatic response to a single dose of infliximab in a patient with prolonged pustular psoriasis derived from inverse psoriasis

We report a case of a 25‐year‐old Chinese man with an exceptionally prolonged history of pustular psoriasis derived from inverse psoriasis who was unsatisfied with conventional treatment and was successfully treated with a single dose of infliximab without noticeable adverse effects. No recurrence or flaring was observed after 3 months of follow‐up. This case illustrates that infliximab may be an effective and safe therapeutic option for patients with refractory pustular psoriasis derived from inverse psoriasis.     

Methotrexate induces apoptotic cell death in human keratinocytes

Abstract The mechanism by which low doses of methotrexate act in psoriasis to restore a clinically normal skin is poorly understood. Apoptosis is a programmed cell death activated when cell removal is needed. The purpose of the present work was to examine using an organotypical model of keratinocyte culture, the possibility that low doses of methotrexate can induce apoptosis of keratinocytes. Epidermal explants were cultivated on dead deepidermized dermis under air-exposed conditions. After 10 days, methotrexate (10^–7 M) was added. After a further 5 days, one part of each culture was fixed and submitted to routine histology, DNA nick end labelling (TUNEL) to detect DNA fragmentation (a molecular marker of apoptotic cell death) and immunohistochemical detection of p53 (a protein involved in apoptosis induced by DNA-damaging agents). The other part of each culture was processed for electron microscopy. A significant proportion of keratinocytes (1%) were damaged and exhibited the morphological features of apoptotic cell death. Immunohistochemical overexpression of p53 was detected in the basal layer of the cultures treated with methotrexate. Low doses of methotrexate induce apoptosis. This mode of action could explain the reduction in epidermal hyperplasia during treatment of psoriasis with methotrexate. Received: 10 March 1997     

C2-ceramide induces apoptosis in a human squamous cell carcinoma cell line

BACKGROUND: Previous studies have demonstrated that synthetic cell-permeable analogues of ceramide promote differentiation and inhibit proliferation of keratinocytes, and that the vitamin D3 inducible sphingomyelin cycle generates ceramide in keratinocytes. Although it has been suggested that exogenous ceramide induces apoptosis of keratinocytes, which is similar to their effect on other cell types, such as leukaemia cells, only a few studies have reported ceramide-induced apoptosis of keratinocytes. OBJECTIVE: To determine whether ceramide induces apoptosis of keratinocytes, we used the synthetic ceramide analogue, C2-ceramide (N-acetylsphingosine) and a human squamous cell carcinoma cell line, HSC-I. METHODS: We treated HSC-I cells with C2-ceramide, followed by a viability assay, morphological observations, nick end-labelling (TUNEL), DNA electrophoresis, and electron microscopy. RESULTS: In the viability assay, C2-ceramide was toxic to HSC-I cells in a dose-dependent manner. Manifestations of apoptotic morphology occurred in the ceramide-treated cells, whereas these morphological changes did not occur in cells treated with dihydroceramide (N-acetylsphinganine). TUNEL revealed that many of the ceramide-treated cells showed positive reactivity. DNA electrophoresis demonstrated that C2-ceramide caused internucleosomal fragmentation in a dose- and time-dependent manner. Electron microscopy revealed that the ceramide-treated cells manifested morphological characteristics typical of apoptosis. CONCLUSIONS: The present results demonstrate that C2-ceramide induces apoptosis of transformed human keratinocytes, whereas C2-dihydroceramide does not have such an effect. The fact that ceramide induces apoptosis of keratinocyctes raises the possibility that intracellular ceramide, which is increased with differentiation of the epidermis, might be involved in terminal differentiation, a specialized form of apoptosis of keratinocytes.     

Barrier repair in chronic plaque-type psoriasis

Purpose: To investigate barrier repair after mild trauma in lesional skin of psoriasis patients with chronic plaque-type disease and to compare this with non-involved psoriatic skin and normal controls.
Methods: Transepidermal water loss (TEWL) readings were taken from involved psoriatic skin and non-involved skin of psoriasis patients as well as the skin of normal controls. Three readings were performed at each site: the basal state, immediately after 20 tape strippings and 1 week post stripping.
Results: Higher baseline, post-stripping and 1-week recovery TEWL readings in psoriatic-involved skin compared to non-involved and normal control skin. No significant difference in barrier recovery rate in psoriatic-involved skin compared to non-involved and normal control.
Conclusion: Although there appears to be a derangement of barrier function in lesional skin of psoriasis patients compared to non-lesional skin and the skin of healthy controls, the barrier recovery function of lesional psoriatic skin is still fully operational.     

CD30+ T-cell lymphoma in a patient with psoriasis treated with ciclosporin and infliximab

There is a known relationship between the use of immunosuppressive therapies and the development of lymphoproliferative malignancies. These lymphomas are mainly B-cell nonHodgkin's lymphomas associated with Epstein-Barr virus. Most cases concern classical immunosuppressive treatments including ciclosporin and methotrexate. A relationship between the new antitumour necrosis factor (TNF)-alpha agents and lymphoproliferative malignancies is debated. Patients with psoriasis on immunosuppressive therapies, mainly ciclosporin, are considered to have a low risk of developing lymphoid proliferation. We report a patient with erythrodermic psoriasis treated with ciclosporin and infliximab who developed a CD30+ T-cell lymphoma. This lymphoma regressed after stopping these treatments. In this case, the anti-TNF-alpha agent may have played a role in association with ciclosporin in the development of the lymphoproliferative disorder. Whereas the combination of anti-TNF-alpha therapies with methotrexate has been well studied, their combination with ciclosporin has been evaluated only in a few patients. Psoriatic patients who may require anti-TNF-alpha treatment have often been or will be treated with ciclosporin. The combination of ciclosporin and anti-TNF-alpha warrants further investigation.     

miRNA调控银屑病角质形成细胞增殖机制的研究进展

MicroRNA（miRNA）在银屑病的发病过程中发挥重要作用,但其调节角质形成细胞增殖的机制尚未明了。本文对miRNA种类及在银屑病中的自调控方式进行了综述。     

Long-term efficacy of a single course of infliximab in hidradenitis suppurativa

BACKGROUND: Hidradenitis suppurativa is a chronic inflammatory skin disease characterized by abscess formation, predominantly in the axillae and groins. The disease is difficult to treat and has a severe impact on quality of life. Recently, several case reports have been published describing successful treatment of hidradenitis suppurativa with infliximab and other tumour necrosis factor alpha inhibitors. OBJECTIVES: To evaluate the long-term efficacy of a single course of infliximab. METHODS: Ten patients with severe, recalcitrant hidradenitis were treated with infliximab (three infusions of 5 mg kg(-1) at weeks 0, 2 and 6) and followed up for at least 1 year. The disease activity was measured using laboratory parameters and a recently developed acne score. The patients rated the efficacy of infliximab on a 10-point scale at regular intervals. Quality of life was measured before and after treatment using the Dermatology Quality of Life Index (DQLI). RESULTS: All patients improved within 2-6 weeks. The average acne score diminished from 164+/-50 (mean+/-SD) before treatment to 89+/-49 after 1 year (P=0.002). The mean CRP (C-reactive protein) was reduced from 31.7 mg mL(-1) to 5.5 mg mL(-1) after 1 month (P=0.015). Patients judged the efficacy with a score of 7.9. The mean DQLI was reduced from 18.4+/-7.9 before treatment to 9.3+/-9.1 after 1 year (P=0.007). In three patients long-lasting improvement was observed, with no recurrence of lesions in a 2-year follow-up period. The other patients showed recurrence of lesions after 8.5 months (range 4.3-13.4 months). CONCLUSIONS: Infliximab is an effective treatment in severe hidradenitis suppurativa, leading to reduction of symptoms for a prolonged period.     

Tyrphostins suppress the growth of psoriatic keratinocytes

Abstract Tyrosine kinase inhibitors of the tyrphostin family which block EGF receptor kinase are reported to arrest the growth of psoriatic keratinocytes in vitro. Three tyrphostins with the potency ratio AG555 >> AG18 >> AG814 were found to arrest growth with no adverse cytotoxic effects. The potency ratio to inhibit keratinocyte proliferation follows their potency to inhibit EGF receptor kinase activity in vitro. These compounds represent novel leads for the therapy of psoriasis.     

英夫利西单抗长疗程治疗关节病型银屑病的临床疗效分析

目的：评价长疗程应用英夫利西单抗治疗关节病型银屑病的临床疗效。方法：随访分析2016年11月至2018年11月就诊于中国人民解放军总医院皮肤科接受英夫利西单抗治疗的关节病型银屑病患者。观察第2周、6周以及此后每间隔8周用药后的关节症状及皮损改善情况以及肿瘤坏死因子-α(TNF-α)等指标的变化。结果：8例患者用药疗程满30周,纳入数据分析, 其中5例满46周。LSD法显示,治疗后患者肿胀关节数（0周VS 30周：t=6.939,P<0.001;0周VS 46周：t=3.822,P=0.019)、压痛关节数（0周VS 30周：t=5.353,P=0.001;0周VS 46周：t=3.132,P=0.035)明显减少,PASI值在第30周时下降最明显（0周VS 30周：t=3.742,P=0.007）, TNF-α水平在第22周最高（0周VS 22周：t=3.569,P=0.009）,超过22周后逐渐降低（30周VS 46周：t=4.104,P=0.009）。 结论：英夫利西单抗能够显著改善关节病型银屑病患者的关节症状和皮损,但长疗程应用时疗效呈降低趋势。     

Disruption of lipid rafts causes apoptotic cell death in HaCaT keratinocytes

Lipid rafts are cholesterol-enriched microdomains in plasma membranes. The functional activity of many membrane proteins, including death and growth factor receptors, depends on their insertion in lipid rafts. We have previously demonstrated the presence of lipid rafts in keratinocytes and shown that lipid rafts are involved in the control of keratinocyte proliferation and metabolic activity. In this work, we investigated the effect of lipid-raft disruption on HaCaT keratinocyte survival. Lipid rafts could be disrupted or rearranged with cholesterol-targeting detergents: methyl-beta-cyclodextrin and filipin III. Moreover, cholesterol oxidation by a specific oxidase or blocking of cholesterol synthesis by mevastatin had a similar effect on lipid rafts. All cholesterol-modifying substances caused cell death in a concentration-dependent manner. More detailed studies on the effects of cyclodextrin revealed apoptotic cell death at concentrations >or=0.5% (w/v). The molecular mechanism of apoptosis precipitated by raft disruption remains unknown but does not seem to be dependent of either membrane permeabilization or cell-cycle arrest imposed by cholesterol-modifying compounds.     

The antiproliferative effect of lectin from the edible mushroom (Agaricus bisporus) on human keratinocytes: preliminary studies on its use in psoriasis

Lectins or agglutinins are proteins with affinity for specific sugar residues. Peanut agglutinin (PNA) and the lectin from the edible mushroom (Agaricus bisporus, ABL) both bind to the disaccharide galactosyl beta-1,3-N-acetyl galactosamine alpha-. This is expressed in keratinocytes as an O-linked chain on CD44, a polymorphic membrane glycoprotein. Many lectins are mitogens and PNA is a mitogen for colonic epithelial cells. However, ABL reversibly inhibits proliferation of colonic cancer cell lines without cytotoxicity and thus has therapeutic potential in situations such as psoriasis where proliferation is increased. We have therefore investigated the effect of ABL on the growth of normal human cultured keratinocytes and a human papilloma virus (HPV)-transformed cell line. In a 5-day dose-response study, keratinocyte growth was greatly reduced by 1.0 microg/mL ABL and completely inhibited by 3.0 microg/mL ABL (ANOVA, P < 0.0001). Exposure to 1.0 microg/mL ABL for only 8 h gave the same growth inhibition as did continued exposure for 3 days. No cytotoxic or morphological changes were observed. An HPV-immortalized cell line was relatively resistant to ABL: in a 5-day dose-response study, exposure to 30 microg/mL was required to inhibit cell growth completely. Topical application of ABL 0.01% or 0.1% to normal human skin caused no change in skin erythema, blood flow or thickness compared with vehicle or baseline (n = 6). ABL 0. 1% in white soft paraffin was compared with vehicle in 11 psoriatic patients, using comparative contralateral plaques. Twice daily application for 2 weeks showed no significant difference from vehicle-treated sites, although the skin thickness of plaques fell from 5.3 +/- 0.4 (n = 11, mean +/- SEM) to 4.1 +/- 0.3 mm. In view of the in vitro results further studies are warranted, particularly if means can be found to improve the epidermal penetration of the relatively large ABL molecule (60 kDa).     

Fluctuations in serum levels of adalimumab and infliximab in patients on stable treatment for psoriasis

Many patients with psoriasis fail to respond to biologic drugs either initially or lose response over time, the latter having predominantly been linked to low circulating drug levels. We examined how serum drug levels varied over three treatment cycles of stable maintenance therapy with either adalimumab or infliximab among a total of 28 patients with psoriasis (22 men, mean age 48.6 years, mean treatment time 6.2 years) and whether there was an association with various patient‐specific factors. The range for all concentrations was 1.1 to 24.3 μg/mL for adalimumab and 0.0 to 180.6 μg/mL for infliximab. There was a consistent inverse association between body mass index (BMI) and trough and maximum serum concentrations of adalimumab (P < .05 for all comparisons) and a positive, less consistent, association between age and maximum serum concentration of infliximab (P < .05 for both comparisons). Patient‐specific factors, such as BMI and age, can help predict fluctuations in serum concentrations of biologics used for psoriasis.     

Treatment of recalcitrant pustular psoriasis with infliximab: effective reduction of chemokine expression

Tumour necrosis factor (TNF)-alpha is thought to play a major role in the pathophysiology of psoriasis. Good clinical responses of psoriasis to anti-TNF-alpha-based therapies have recently been demonstrated. We studied the effect of infliximab, a monoclonal antibody against TNF-alpha, on chemokine expression in pustular psoriasis. A 61-year-old man with a 2-year history of severe pustular psoriasis of von Zumbusch type who did not respond to conventional therapies responded rapidly to treatment with infliximab. The clinical response was reflected by an immediate and effective reduction of the neutrophil-attractant chemokines interleukin (IL)-8 and growth-related oncogene (Gro)-alpha as well as of monocyte chemoattractant protein (MCP)-1, as determined by mRNA in situ hybridization of lesional skin. No expression before or after treatment was seen for monokine induced by interferon (IFN)-gamma (MIG) and IFN-inducible protein (IP)-10. Thus, in pustular psoriasis the chemokine expression pattern is dominated by neutrophil-attractant chemokines and MCP-1 while, in contrast to plaque psoriasis, IFN-gamma-inducible lymphocyte-attractant chemokines such as IP-10 and MIG are not abundant. We conclude that anti-TNF-alpha treatment with infliximab is an effective therapy in severe pustular psoriasis which is reflected by downregulation of disease-promoting chemokines such as IL-8, Gro-alpha and MCP-1.     

Merkel cell carcinoma showing regression after biopsy: Evaluation of programmed cell death 1‐positive cells

We present a cases of Merkel cell carcinoma (MCC) with Merkel cell polyomavirus that showed complete regression after biopsy. The exact mechanism of regression in MCC has remained unclear. It has been reported that apoptosis caused by T‐cell immunity was implicated in the regression, and programmed cell death 1 (PD‐1), an inhibitory receptor, was expressed in approximately half of tumor‐infiltrating T cells in MCC. However, the contribution of PD‐1‐positive cells for the regression of MCC has not been evaluated. We examined the rate of PD‐1‐positive cells among the peritumoral mononuclear cells, which showed that the percentage of PD‐1‐positive cells in the case was significantly lower compared with in MCC without regression. We propose that PD‐1‐positive cells suppress tumor immunity for MCC, and that reduction of PD‐1‐positive cells may be associated with tumor regression.