Telomerase activity is usually detected in most tumor tissues but not in normal tissues. Recently, there is increasing evidence that telomerase activity is associated with cell proliferation without malignancy, whereas there is little information about telomerase activity and its relationship with cell proliferation in chronic hyperproliferative skin diseases. Thus, we studied telomerase activity in skins from 10 patients with psoriasis and compared telomerase activity with the expression of Ki-67, a proliferation marker, using immunohistochemical staining. The effect of retinoic acid on the telomerase activity in HaCaT cells was also evaluated. Telomerase activity was detected in 7 (70%) of 10 lesional skins of psoriasis and none of the nonlesional skin. Telomerase activity in lesional skin was significantly associated with Ki-67 labelling index. Retinoic acid treatment on HaCaT cells inhibited telomerase activity, which correlated with inhibition of cell proliferation by the agent. The results of our study represent another example that shows telomerase activity correlates with cellular proliferation. Further studies on the regulation of the telomerase are needed to understand the cellular factors involved in controlling telomerase activity.
Cell Division/drug effects ; Cell Line ; Enzyme Inhibitors/*pharmacology ; Human ; Ki-67 Antigen/*analysis ; Psoriasis/*enzymology ; Skin/*enzymology ; Telomerase/antagonists & inhibitors/*metabolism ; Tretinoin/*pharmacology

In a previous search for the differentially expressed genes in keratinocyte differentiation, we identified neutrophil gelatinase-associated lipocalin (NGAL) as a calcium- induced gene. In this study, we further verified the expression of NGAL in cultured keratinocytes as well as in several skin diseases. Reverse transcription-polymerase chain reaction (RT-PCR), Western blot, and ELISA clearly showed that NGAL expression was markedly increased in calcium-induced keratinocyte differentiation in vitro. However, in our previous report, NGAL expression was not detected in normal skin tissue except for hair follicle by in situ hybridization and immunohistochemistry, indicating the difference of cell status between in vitro and in vitro conditions. Interestingly, NGAL expression was highly increased in psoriasis-like inflammatory disorders (lichen planus and pityriasis rubura pilaris) and skin cancers (keratoacanthoma and squamous cell carcinoma), implying that NGAL may be related with the epidermal hyperplasia. Collectively, these results reveal the potential importance of NGAL in the maintenance of skin homeostasis.
Acute-Phase Proteins/*biosynthesis ; Calcium/*metabolism ; Cell Differentiation ; Culture Media ; Culture Media, Conditioned ; Enzyme-Linked Immunosorbent Assay ; *Gene Expression Regulation ; Homeostasis ; Humans ; Keratinocytes/enzymology ; Lipocalins/*biosynthesis ; Models, Biological ; Proto-Oncogene Proteins/*biosynthesis ; Psoriasis/enzymology ; Reverse Transcriptase Polymerase Chain Reaction ; Skin/*metabolism ; Skin Neoplasms/enzymology

OBJECTIVETo investigate the levels of cytokines related to T-helper (Th) 17 cells in serum and signal transducers in the psoriatic lesions of patients with psoriasis vulgaris of blood-heat syndrome (BHS) and blood-stasis syndrome (BSS).

METHODSSixty patients with psoriasis vulgaris were divided into the BHS and BSS groups according to the syndrome differentiation of Chinese medicine (CM). Ten healthy subjects were considered as the control group. Cytokine levels of interleukin (IL)-17, IL-23 and IL-6 in serum were determined by enzyme-linked immunosorbent assay. Expression levels of signal transducer and activator of transcription 3 (STAT3), p38-mitogen-activated protein kinase (MAPK) and STAT6 in the psoriatic lesions were determined using immunohistochemistry (IHC), Western blot, and real-time quantitative reverse transcription polymerase chain reaction, respectively.

RESULTSProduction of IL-17, IL-23 and IL-6 in the BHS group and BSS group were significantly increased compared with those in the control group (P<0.05). Levels of IL-17 and IL-23 in the BHS group were higher than those in the BSS group (P<0.05). Compared with the control group, IHC positive expressions and protein expressions of STAT3 and p38-MAPK, and the STAT3 mRNA expressions in the BHS and BSS groups were significantly higher (P<0.05 or P<0.01). The protein expression of STAT3 in the BHS group was significantly higher than that in the BSS group (P<0.05).

CONCLUSIONSCytokines in serum and signal transducers in the psoriatic lesions alter with various CM syndromes of psoriasis. The results provide scientific basis for the treatment based on syndrome differentiation of CM in treating psoriasis vulgaris.

Adult ; Female ; Gene Expression Regulation ; Humans ; Immunohistochemistry ; Interleukin-17 ; blood ; Interleukin-23 ; blood ; Interleukin-6 ; blood ; Male ; Psoriasis ; blood ; enzymology ; genetics ; immunology ; RNA, Messenger ; genetics ; metabolism ; STAT3 Transcription Factor ; genetics ; metabolism ; STAT6 Transcription Factor ; genetics ; metabolism ; Signal Transduction ; Syndrome ; Th17 Cells ; immunology ; p38 Mitogen-Activated Protein Kinases ; genetics ; metabolism