c－myc、p53和bcl－2与银屑病角质形成细胞凋亡异常关系的研究

目的 探讨原癌基因ｃ－ｍｙｃ、抑癌基因ｐ５３和凋亡保护基因ｂｃｌ－２在银屑病角质形成细胞凋亡异常中的作用。方法 采用免疫组化和非同位素核酸原位杂交技术从蛋白和ｍＲＮＡ二个水平检测了３６份建党型银屑病皮损中ｃ－ｍｙｃ、ｐ５３和ｂｃｌ－２的表达状况。结果 银屑病表皮中的ｃ－ｍｙｃ、ｐ５３和增殖细胞核抗原（ＰＣＮＡ）阳性细胞较正常皮肤明显增加,而ｂｃｌ－２阳性细胞在表皮基底层中明显减少。在ＰＣＮＡ阳性细     

A comparison of Ki-67 antigen presentation in acute generalized exanthematous pustulosis and pustular psoriasis

Ki-67 is an established marker of cell proliferation. It is highly expressed in psoriasis and correlated with the clinical severity of psoriasis. Higher number of Ki-67 positive keratinocytes has been observed in pustular psoriasis (PP) as compared with psoriasis vulgaris. As for Acute generalized exanthematous pustulosis (AGEP), a distinct disease entity but similar in many aspects of clinicopathologic features to PP, Ki-67 immunostaining presentation has never been investigated before. This study aimed to compare Ki-67 immunostaining presentation between PP and AGEP. By immunohistochemical staining, we compared Ki-67 immunostaining presentation on skin lesions of five patients of AGEP and five age-matched patients of PP. Ki-67 positive keratinocytes were counted and mean values were determined to compare between PP and AGEP. An augmented presence of Ki-67 positive keratinocytes was found in both AGEP and PP and they distributed not only in basal cell layer but in middle or even upper part of epidermis. Statistical analysis using Mann–Whitney U test showed no difference of epidermal proliferation rate between the two groups (P = 0.222). The results showed there was no difference of Ki-67 immunostaining presentation between AGEP and PP. Besides, we found marked increase of Ki-67-positive proliferating keratinocytes in AGEP and suggested that epidermal hyperproliferation may also play an important role in the formation of AGEP. We also discussed the possible pathophysiology of AGEP, possible epidermal architecture changes in AGEP and PP, and found the similarity in pathophysiology of AGEP and PP.     

The temporal and spatial distribution of p21WAF expression in skin appendages

p21WAF is a cyclin-dependent kinase inhibitor which is widely expressed in epidermal structures. Using a combination of double immunocytochemical staining and combined in situ hybridization, we show that there is a striking exclusivity between the expression of Ki67 and p21WAF in the hair matrix. Some cells that are Ki67-positive also express p53, but as they exit the cell cycle they assume p21WAF-positive/p53-negative status. By contrast, cells in the interfollicular epidermis of psoriatic lesions, in the sebaceous gland, and in the outer root sheath are p21WAF-positive/p53-positive but Ki67-negative. These results suggest that in some anatomical parts of the epidermis, p21WAF expression can accompany p53 expression, whereas in other parts, the expression of these markers is reciprocal, suggesting that other pathways may be controlling p21WAF expression. In order to define, functionally, the presence of p53-independent p21WAF expression in skin, we examined lesions of Bowen's disease in which both alleles of p53 were inactivated. p21WAF expression was still observed, confirming a role for p53-independent expression of p21WAF in human skin in vivo.     

Detection of nitric oxide and nitric oxide synthases in psoriasis

Biopsies from psoriasis lesions and clinically uninvolved skin of eight patients and five normal subjects were studied by immunocytochemistry with computerized image analysis for the presence of endothelial, neuronal and inducible isoforms of nitric oxide synthase. Endothelial nitric oxide synthase was expressed in the endothelium and weakly in some keratinoctyes. Its expression was not significantly different in psoriasis. Inducible nitric oxide synthase, however, was absent from normal skin but was significantly upregulated in psoriatic lesional skin, focally in keratinocytes but to the greatest extent in the papillary dermis and to a lesser extent in clinically uninvolved psoriatic skin. Inducible nitric oxide synthase staining was greatest in the more severe lesions and correlated with the inflammatory infiltrate (CD3-positive cells) and with keratinocyte proliferation (Ki-67-positive cells). In normal skin, neuronal nitric oxide synthase was expressed only in keratinocytes in the granular layer and eccrine sweat glands. However, in psoriasis and clinically uninvolved skin the neuronal form was present through all levels of the epidermis. Direct measurement of nitric oxide production from the skin surface revealed a tenfold increase in the lesions of 16 psoriatic patients compared with their nonlesional skin, and this nitric oxide production was inhibited by topical betamethasone. Received: 4 March 1996     

The effects of calcipotriol and methylprednisolone aseponate on bcl-2, p53 and ki-67 expression in psoriasis

OBJECTIVE: The decrease of physiological apoptosis in the psoriatic lesions is thought to be involved in the pathogenesis of psoriasis, and induction of apoptosis was shown to contribute to the regression of psoriatic hyperplasia. In the present study, we compared the effects of calcipotriol and methylprednisolone aseponate (MPA) treatments on bcl-2, p53 and ki-67 expressions in psoriatic patients in order to define a relationship between regulation of apoptosis and healing process in psoriasis. METHODS: Thirty psoriatic patients with stable and moderate chronic plaque psoriasis applied either calcipotriol or MPA ointment for 6 weeks twice daily. Evaluation of bcl-2, p53 and ki-67 positivity was performed at baseline and was repeated at sixth week for each therapy. RESULTS: The mean percentage of positive keratinocytes was 8.63 +/- 7.15% for p53, 20.66 +/- 14.45% for ki-67, and 3.74 +/- 2.83% for bcl-2 in psoriatic skin at baseline. Normal skin values were 3.27 +/- 3.21% for p53, 4.93 +/- 4.77% for ki-67, and 1.80 +/- 0.41% for bcl-2. The psoriatic skin showed higher ki-67 (P < 0.05) and bcl-2 (P < 0.05) expression rates when compared to normal skin. The p53 positivity observed in psoriatic skin and normal skin was not significantly different (P > 0.05). Following calcipotriol and MPA treatments, there was a significant reduction in p53 and ki-67 positivity accompanied by an increase in bcl-2 positivity (P < 0.05 each). No significant differences were found at sixth week between calcipotriol and MPA groups with respect to p53, ki-67 and bcl-2 positivity (P > 0.05). The post-treatment psoriatic skin showed lower expression of p53, higher expressions of ki-67 and bcl-2 when compared to normal skin (P < 0.05 each). CONCLUSION: The results of this study provide evidence that both calcipotriol and MPA decrease the p53 and ki-67 expression and increase bcl-2 expression. However, it should further be elucidated if these changes were the common behaviour of psoriatic keratinocytes to any antipsoriatic medication.     

Local effects of TL01 phototherapy in psoriasis

The mechanisms whereby narrowband ultraviolet B (UVB) (311-313 nm, TL01) phototherapy are effective in psoriasis may differ from those occurring in broadband UVB phototherapy. In the present study, changes in epidermal cells as a result of TL01 therapy were assessed in the skin of patients with psoriasis. The non-lesional skin of five subjects with plaque psoriasis was biopsied before and after a series of 12 whole-body TL01 treatments. Following appropriate staining of skin sections, the numbers of p53-positive keratinocytes, sunburn cells and Langerhans cells in the epidermis were counted. TL01 therapy induced a threefold increase in the number of p53-positive epidermal cells, a 12-fold increase in sunburn cells and a twofold decrease in Langerhans cells. The increase in epidermal p53 expression and apoptosis of keratinocytes together with the depletion of Langerhans cells in the non-lesional skin of psoriasis patients are likely to contribute to the effectiveness of TL01 phototherapy.     

Proliferation antigens in cutaneous melanocytic tumors--an immunohistochemical study comparing the transferrin receptor and the Ki 67 antigen

The cellular reactivities with the monoclonal antibodies OKT9 and Ki 67 have been demonstrated to be closely related to proliferation in various malignant neoplasms. In this study a total of 25 melanocytic skin tumors was examined immunohistochemically with both antibodies and the results were evaluated semiquantitatively for OKT9 and quantitatively for Ki 67 by stereological methods. All cases of primary and metastatic malignant melanoma expressed a strong stainability for OKT9, whereas benign melanocytic nevi were almost completely negative. Our results with the monoclonal antibody Ki 67 revealed highly significant differences in the numerical density of Ki-67-positive cells between metastatic malignant melanoma (number of positive cells: 47.0 +/- 9.2 X 10(3)/mm3), primary malignant melanoma (6.3 +/- 1.9 X 10(3)/mm3) and benign melanocytic nevi (2.2 +/- 0.7 X 10(3)/mm3). Correlation analysis between mean percentage of OKT9-positive cells and numerical density of Ki-67-positive cells revealed a significant correlation of both parameters (r = 0.58; p less than or equal to 0.05), indicating a positive relationship of OKT9 and Ki 67 expression. Especially in primary malignant melanoma, however, the amount of OKT9-positive cells considerably exceeds that of Ki-67-positive cells. The monoclonal antibodies OKT9 and Ki 67 reflect 'proliferative activity' in melanocytic skin tumors, as both are expressed in significantly higher amounts in primary and metastatic malignant melanomas. The combined application of these antibodies in cutaneous melanocytic lesions might be of diagnostic and prognostic value.     

Increased expression of CD208 (DC-LAMP) in epidermal keratinocytes of psoriatic lesions

Psoriasis is a chronic inflammatory skin disease characterized by epidermal hyperproliferation and infiltration of inflammatory leukocytes. The aim of this study was to clarify the role of innate immunity involving dendritic cells (DC) and keratinocytes in psoriasis. We immunohistochemically examined the expression of DC markers such as CD1a, CD83, CD207 (Langerin), CD208 (DC-LAMP) and CD209 (DC-SIGN) in psoriatic skin and γ-interferon (IFN-γ)/12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated keratinocytes in vitro . CD208 was strongly expressed in basal and suprabasal layer keratinocytes in addition to DC in the perivascular lesions of the psoriatic dermis. Furthermore, the enhanced expression of CD208 in the perinuclear lesions of IFN-γ-/TPA-stimulated keratinocytes was observed in vitro . Because a defect of the granular layer in psoriatic lesions has been recognized, increased expression of lysosome-related CD208 in the basal and suprabasal keratinocytes of psoriatic lesions might represent aberrant epidermal differentiation. Additionally, these CD208-positive keratinocytes possessing putative antigen-processing activity might play a key role as antigen-presenting cells in psoriatic skin.     

Neutrophil elastase promotes proliferation of HaCaT cell line and transwell psoriasis organ culture model

Background Neutrophil elastase (NE) plays an important role in psoriasis. In this study we observed the effect of NE on the proliferation of HaCaT cells and transwell psoriasis organ culture model and investigated the mechanism. Methods HaCaT cells were treated with various concentrations NE (0, 0.1, 1, 10, 100 IU/l). In addition, the cells were co‐stimulated with 10 IU/l NE and 1 g/l sivelestat. Then, HaCaT cells proliferation and DNA synthesis were determined using methyl thiazolyl tetrazolium (MTT) and tritiated thymidine (3H‐TdR) assay respectively. Cell cycle distribution was measured using fluorescence activated cell sorting (FACS). Subsequently, we established cultured transwell psoriasis organ model in vitro. Then, the cultured transwell psoriasis organ model was treated with 10 IU/l NE. Immunohistochemistry was employed to detect the expression levels of Ki67 and p53 in the cultured transwell psoriasis organ model. Results MTT and 3H‐TdR incorporation assay suggested NE could remarkably promote the proliferation and DNA synthesis of HaCaT cell in a dose‐dependent manner. After NE treatment (10 IU/l) for 24 h, the cell fraction of HaCaT cell in G2 + S phase was increased significantly, whereas the cell fraction in G1 phase was reduced remarkably. Immunohistochemistry results revealed enhanced expression of both Ki67 and p53 genes in cultured transwell psoriasis organ model after NE treatment. Conclusions NE significantly promotes the proliferation of HaCaT cell. Meanwhile, it also up‐regulates the expression levels of Ki67 and p53 in psoriasis lesion tissue, which plays an important role in the pathogenesis of psoriasis lesion.     

Increased expression of an epidermal stem cell marker, cytokeratin 19, in cutaneous squamous cell carcinoma

Background Cytokeratin 19 (CK19) has been considered to be a putative marker for epidermal stem cells in the hair follicle bulge. Cumulative reports have shown that epidermal stem cells play an important role in skin carcinogenesis. However, to date there has been no report on the clinical alteration of the stem cells in squamous cell carcinoma (SCC). Objectives To investigate alteration of the stem cells and proliferating cells and to assess their relationship and potential contribution to SCC. Methods Thirty paraffin‐embedded neoplastic skin lesions, consisting of 10 cases each of actinic keratosis (AK), Bowen disease (BD) and SCC, were examined immunohistologically for CK19 and Ki‐67. Results Positive reactivity for CK19 was seen in 30% of AK, 50% of BD and 80% of SCC lesions. There was significantly higher expression levels of CK19 in SCC than in AK and BD (P < 0·05). In addition, BD lesions harboured a significantly higher number of CK19‐positive cells than did AK lesions (P < 0·05). There were significant differences in Ki‐67 labelling indices between AK and BD and between AK and SCC (P < 0·001), but not between BD and SCC (P > 0·05). Furthermore, a serial section comparison study showed that there was a minor population of cells co‐expressing CK19 and Ki‐67 in a subset of the tumour cells of SCC samples. The percentage of CK19+ cells significantly correlated with that of Ki67+ cells in all examined neoplastic skin lesions. Conclusions These results suggest that CK19 expression may be associated with the retention of stem cell characteristics or a state that is uncommitted to terminal squamous differentiation.     

Immunohistochemical Studies of Infiltrating Cells in Early and Chronic Lesions of Psoriasis

The expression of surface antigens on infiltrating cells, epidermal keratinocytes, and dendritic cells in biopsy specimens from 31 patients with psoriasis was examined immunohistochemically. The specimens were divided into early-phase and chronic-phase groups and then examined in a double blind manner. Among the infiltrating cells in the epidermis, CD4-positive cells were dominant in the early phase; CD8-positive cells were dominant in the chronic phase, resulting in a markedly decreased CD4/CD8 ratio in the latter. On the other hand, among the infiltrating cells in the dermal papillae, CD4-positive cells were dominant in both the early and chronic phases; both CD4-positive and CD8-positive cells were more dominant in the chronic phase than in the early one. However, the CD4/CD8 ratios were decreased in both the dermal papillae and the epidermis in the chronic phase. CD1-positive dendritic cells (probably Langerhans cells) were more numerous in the chronic phase than in the early phase. There were no significant differences between the early and chronic phases with regard to the expression of HLA-DR and HLA-DQ antigens on the infiltrating cells. However, the HLA-DR antigens and ICAM-1 (intercellular adhesion molecule-1) were more strongly expressed on epidermal keratinocytes in the chronic phase than in the early phase. LFA-1α (lymphocyte function-associated antigen-1α)-positive cells were also significantly more numerous in the chronic phase than in the early one, consistent with the expression of HLA-DR antigens and ICAM-1 on keratinocytes mentioned above. On the other hand, VLA-4 (integrin α₄β₁) positive cells were expressed more abundantly in the epidermis in the early phase than in the chronic phase. These results suggest, first, that the chronic phase of psoriasis is as immunologically active as or more active than the early phase. Second, CD4-positive T cells are more important than CD8-positive T cells in the early phase of psoriasis; CD8-positive rather than CD4-positive T cells are more important in the chronic phase. Third, the LFA-1/ICAM-1 pathway may play an important role with regard to cell adhesion of the infiltrating cells in the psoriatic lesions in disease exacerbation or prolongation, whereas the VLA-4/VCAM-1 (vascular cell adhesion molecule-1) pathway may be more important in disease onset.     

Differential proliferation of endothelial cells and keratinocytes in psoriasis and spongiotic dermatitis

This study used MIB-1 monoclonal antibody to quantify the proliferating keratinocytes and endothelial cells and their proliferation fractions in cases of normal skin, acute and established plaque psoriasis, and acute and chronic spongiotic dermatitis. The number and the proliferation fraction of MIB-1 positive cells were higher in psoriatic and chronic spongiotic lesions than in normal skin (p < 0.05). Established plaque psoriasis had a higher number of proliferating keratinocytes and a higher keratinocytic proliferation fraction than did acute psoriasis (p < 0.05). The number of proliferating endothelial cells decreased as acute psoriatic lesion became chronic, but the number in acute spongiotic lesion increased as it became chronic. The endothelial proliferation fraction was higher in acute psoriasis than in established plaque psoriasis (p < 0.05). The ratio of keratinocytic proliferation fraction to endothelial cell proliferation fraction of the psoriatic and spongiotic lesions suggested the presence of different reaction patterns to inflammation in psoriasis and spongiotic dermatitis.     

Matrix metalloproteinase-19 is expressed by keratinocytes in psoriasis

Keratinocyte hyperproliferation, inflammatory infiltrates, neoangiogenesis and alterations in cytokine levels are hallmarks of psoriatic skin. Matrix metalloproteinases (MMPs) have been associated with the remodeling of the extracellular matrix during inflammation, neovascularization, and malignant transformation. We have previously shown that particularly MMP-12 is abundantly expressed by macrophages and MMP-9 in macrophages and neutrophils of psoriatic lesions. In this work the expression of two novel metalloproteinases, MMP-19 and MMP-28, was investigated in psoriatic lesional and non-lesional skin. MMP-19 protein was detected by immunohistochemistry in 28/29 samples in keratinocytes in the same regions as Ki67 (marker of proliferating keratinocytes) and p63 (marker of keratinocyte stem cells). Immunosignaling was also seen in endothelial cells and fibroblasts. Furthermore, MMP-19 mRNA was upregulated in psoriatic keratinocytes and skin as assessed by quantitative real-time polymerase chain reaction. In lichen planus and lichenoid chronic dermatitis, MMP-19 staining was found in keratinocytes in areas where the basement membrane was abnormal. MMP-28 was not detected in psoriatic or non-lesional skin. Our results suggest that keratinocytes as well as the previously reported cell types (smooth muscle, endothelial and macrophages) can express MMP-19 in psoriasis and lichen planus. Upregulation of MMP-19 in keratinocytes may be influenced by changes in the architecture of the basement membrane zone.     

Expression profiles of ProEx C and Ki67 in squamous cell carcinoma in situ of the skin and their relationship with human papillomavirus genotypes

Background: ProExC is a new marker for identification of precursor lesions of cervical carcinoma. Its utility in noncervical squamous cell carcinoma in situ (SCCIS) such as Bowen's disease (BD) and actinic keratosis (AK) where human papillomavirus (HPV) plays a role has not been elucidated. Our aim was to ascertain the immunohistochemical features and clinical utility of ProExC in SCCIS of the skin. Methods: HPV presence was tested in SCCIS (38 BD and 7 AK) using GP5+/6+ and Short PCR fragment (SPF) primers and subsequently genotyped. Histopathologic sections were stained for ProExC and Ki67. A set of non‐neoplastic skin proliferative lesions were included for immunohistochemical evaluation [14 psoriasis (PS) and 6 psoriasiform dermatitis (PSD)]. Results: HPV was detected in 18.9% BD. ProExC and Ki67 in the whole epidermis thickness was observed in 86.5 and 37.1% BD, respectively (p < 0.0001). ProExC and Ki67 were restricted to the lower third of the epidermis in PS and PSD. Conclusions: ProExC expression is not associated with HPV in SCCIS of the skin. Proliferating cells are better delineated in SCCIS by ProExC which may be useful to assess the extent of these lesions. Different immunohistochemical profiles seen in neoplasic and non‐neoplastic skin lesions suggest diverse alteration of cell‐cycle kinetics. Sánchez‐Hernández M, Conesa‐Zamora P, García‐Solano J, Corbalán‐Vélez R, Martínez‐Barba E, Pérez‐Guillermo M. Expression profiles of ProEx C and Ki67 in squamous cell carcinoma in situ of the skin and their relationship with human papillomavirus genotypes.     

p73蛋白在正常人皮肤和表皮肿瘤中的表达

目的 探讨p73蛋白在正常人皮肤和不同表皮肿瘤皮损中的表达及意义。方法 应用免疫组化方法检测19例脂溢性角化病、16例基底细胞癌、11例Bowen病、5例鳞状细胞癌及10例正常人皮肤p73、p53、Ki67的表达。结果 在正常人表皮基底层、毛囊外毛根鞘最外层基底样细胞和皮脂腺生发细胞有p73的表达;在基底细胞癌和脂溢性角化病的基底样细胞、Bowen病中异形性明显的瘤细胞p73呈高表达,鳞状细胞癌和脂溢性角化病中的鳞状细胞呈弱阳性或不表达。脂溢性角化病、Bowen病、基底细胞癌、鳞状细胞癌之间p73蛋白表达差异有统计学意义(H=12.71,P<0.01),其中基底细胞癌的表达最强。Ki67在皮肤肿瘤之间差异也有统计学意义(H=14.12,P<0.01),但p53差异无统计学意义(H=2.058,P>0.05)。在各组样本中,p73的表达与p53、Ki67无显著相关性(P>0.05)。结论 p73蛋白可能在皮肤分化中起重要作用。     

Low frequency of genetic change in p53 immunopositive clones in human epidermis

Sun-exposed skin of Caucasians harbors thousands of p53-mutated clones, which are clinically invisible. Using whole mount immunostaining for p53 or Ki67 antigens, p53 sequencing, and loss of heterozygosity analysis, we have further characterised these clones. Loss of heterozygosity for the alleles examined is uncommon with the exception of 9q, which occurred in 28.3% of the samples. P53 clones are more common and larger in individuals with basal cell carcinoma than in control subjects (p < 0.03). Loss of heterozygosity is also more common in clones from individuals with basal cell carcinoma than in clones from subjects without a history of basal cell carcinoma, as would be expected if both relate to ultraviolet radiation exposure. p53 sequencing of clones is in keeping with the mutagenic role of ultraviolet radiation. Surprisingly, skin found to harbor p53 clones showed no clusters of Ki67 positive cells, unlike the situation for actinic keratoses or basal cell carcinomas. These results show that in human skin p53 mutation is not directly associated with genomic instability or abnormal cell cycling; that the p53 immunopositive clones are either genetically distinct or precursors to other squamous cell lesions of skin; and that p53 immunopositive clones are early lesions, in that gross disturbance of proliferation has not already occurred.     

An immunohistochemical study of abnormal keratinocyte proliferation in molluscum contagiosum

BACKGROUND: Molluscum contagiosum is a common cutaneous tumour that is characterized by usually spontaneous involution and self-limited spreading in immunocompetent individuals. OBJECTIVE: We aimed to investigate the apoptosis and the expression of cell-cycle proteins in molluscum contagiosum lesions. METHODS: The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL)-based apoptotic index and the expression of the cell-cycle proteins Ki-67, p53, p21WAF and Bcl-2 were investigated in molluscum contagiosum lesions obtained from the trunk of 20 immunocompetent patients and in normal skin samples from the trunk of six healthy volunteers. RESULTS: Whereas molluscum contagiosum lesions displayed a TUNEL-based apoptotic index similar to that of normal skin, they exhibited an increased Ki-67 index, which was confined to the basal and first suprabasal layers (P < 0.001). Compared with normal non-sun-exposed skin, molluscum contagiosum lesions also exhibited increased p53 staining in basal cells (P < 0.01), increased p21WAF in suprabasal cells (P < 0.001) and loss of Bcl-2 expression. CONCLUSIONS: These results indicate that molluscum contagiosum lesions exhibit an increased proliferation rate of keratinocytes, which is likely to be partially counteracted by accumulation of p53.