[Alteration of retinoid X receptor alpha mRNA level after acitretin and/or narrow-band UVB treatment in normal human keratinocytes].

OBJECTIVE: To investigate the alteration of retinoid X receptor alpha (RXRalpha) mRNA level in normal human keratinocytes after acitretin and/or NB-UVB irradiation treatment. METHODS: After a 12-hour incubation with 10(-7)-10(-6) mol/L acitretin and/or following 50-100 mJ/cm2 NB-UVB irradiation in normal human keratinocytes, RXRalpha mRNA expression was examined by reverse transcription polymerase chain reaction (RT-PCR) and real-time quantitative RT-PCR. RESULTS: The expression of RXRalpha mRNA was obviously decreased by NB-UVB irradiation, but not by acitretion single treatment. When combining acitretin treatment with NB-UVB irradiation, greater decreased RXRalpha mRNA expression was observed than that of single treatment. CONCLUSION: Narrow-band UVB irradiation treatment can decrease RXRalpha mRNA expression, but not acitretin single treatment. Combining treatment with both can produce synergistic inhibition effects.

Semaphoring mAb: a new guide in RIT in inhibiting the proliferation of human skin carcinoma.

Semaphoring is a transmembrane receptor which participates in many cytokine-mediated signal pathways that are closely related to the angiogenesis, occurrence and development of carcinoma. The present study was designed to access the effect of mono-antibody (mAb) guided radioimmunotherapy (RIT) on skin carcinoma and investigate the potential mechanisms. Semaphoring mAb was acquired from mice (Balb/c), purified with rProtein A column; purity, concentration and activity were tested with SDS-PAGE and indirect ELISA; specificity and expression on the cutanuem carcinoma line and tissue were tested by Western blotting; morphology change was assessed by microscopy. MTT assay and colony inhibition tests were carried out to test the influence on the proliferation of tumor cells; Western blotting was also carried out for expression of apoptosis-associated (caspase-3, Bax, Bcl-2) and proliferation-related (PI3K, p-Akt, Akt, p-ERK1/2, ERK1/2) proteins and analyse the change in signal pathways (PI3K/Akt and MEK/ERK). The purity of purified semaphorin mAb was 96.5% and the titer is about 1?106. Western blotting showed semaphoring mAb to have specifically binding stripes with semaphoring b1b2 protein, B16F10, and A431 cells at 39KDa, 100KDa and 130KDa, respectively. Positive expression was detected both in cutanuem carcinoma line and tissue and it mostly located in cell membranes. MMT assay revealed dose-relate and time-relate inhibitory effect of semaphorin mAb on A431 and B16F10. Colony inhibition tests also showed dose-relate inhibitory effects. Western blotting demonstrated the expression of apoptosis and proliferation-related protein and changes in signal pathway. In conclusion, we demonstrated that semaphorin is highly expressed on the tumor cell-surfaces and RIT with semaphorin mAb has effect in inhibiting proliferation and accelerating apoptosis of tumor cells.

Expressions of oncogenes c-fos and c-myc in skin lesion of cutaneous squamous cell carcinoma.

OBJECTIVES: To explore the expressions of c-fos and c-myc in skin lesion of cutaneous squamous cell carcinoma (CSCC). METHODS: Using retrospective analysis, 73 cases of CSCC were selected from Department of Dermatology, the Second Affiliated Hospital of Xi'an Jiaotong University, which were removed between January 2000 and January 2012. It was considered as experimental group. Meanwhile, 11 cases of normal skin specimens of non tumor patients were selected as control group. The expression level of c-fos and c-myc was compared in the two groups. RESULTS: The expressions of c-fos [72.60% (53/73)] and c-myc [83.56% (61/73)] in experimental group were statistically significant (P≤0.05) compared with control group (0%). Expression of c-myc protein was negatively related to differentiation of CSCC. The difference was statistically significant (χ(2)=7.26, P=0.001<0.05). While expression of c-fos protein was positively related to differentiation of CSCC, which was statistically significant (χ(2)=7.47, P=0.001 2<0.025). CONCLUSIONS: The expression level of c-fos and c-myc can be used as an important indicator of CSCC differentiation, and it has closely connection with the differentiated degree, which can guide clinical prognosis.

Isolation and antitumor activities of acidic polysaccharide from Gynostemma pentaphyllum Makino.

Two acidic polysaccharides (GP-B1 and GP-C1) were obtained from Gynostemma pentaphyllum. The molecular weights (Mw) of the two fractions were 79 kDa for GP-B1 and 126 kDa for GP-C1. GP-B1 was composed of Gal, Ara, Man, Rha, Xyl, Glc, GalA and GlcA in a molar ration of 3.5:3.2:0.6:0.9:0.3:0.5:0.6:0.4. GP-C1 consisted of Gal, Ara, Man, Rha, Glc, and GlcA in the proportions of 2.1:1.0:0.3:0.5:0.4:0.9. Among them, GP-B1 treatment had a significant inhibitory effect on the growth of melanoma B16 in vivo and in vitro. Meanwhile GP-B1 could increase the relative spleen weight and stimulate the splenocyte proliferation alone or combined with ConA. Moreover, GP-B1 treatment induced an evident increase in the level of serum TNF-α, IFN-γ, and IL-12 and a reduction for IL-10 production. These results indicate that the antitumor effects of GP-B1 are associated with immunostimulation.

Purification of a polysaccharide from Gynostemma pentaphyllum Makino and its therapeutic advantages for psoriasis.

In current study, a water-soluble polysaccharide (GP-I), with a molecular mass of 33 kDa, was purified from Gynostemma pentaphyllum. Gas chromatography (GC) analysis suggested that it was composed of Glc, Gal, Man, Rha and Ara with a ratio of 5.3: 4.2: 3.0: 0.7: 0.8. The GP-I (25, 50, 100, 200 and 400 µg/ml) was found to have significant anti-proliferative effects on HaCat cells in a dose-dependent manner, as measured by MTT assay. On the contrary, Trypan blue exclusion experiment indicated that GP-I had no cytotoxicity to HaCat cells. Moreover, the decrease of mitochondrial membrane potential (MMP) in GP-I treated cells was also observed, indicating apoptosis in HaCat cells. Besides, tumor necrosis factor-α (TNF-α), a vital pro-inflammatory cytokine in psoriasis, in the supernatant of HaCat cells was dramatically reduced by GP-I. Collectively, these findings suggested that GP-I was a promising agent to be developed for psoriasis treatment in clinical therapy.

[Alteration of tazarotene induced gene-2 expression in psoriasis vulgaris].

OBJECTIVE: To investigate the role of tazarotene induced gene-2 (TIG2) in psoriasis vulgaris. METHODS: TIG2 protein and mRNA expressions in normal tissues, psoriatic lesions and uninvolved skin tissues were detected by immunohistochemistry and in situ hybridization, respectively. RESULTS: TIG2 protein and mRNA were expressed in all the layers of normal and uninvolved epidermis. TIG2 expression was detected in the upper layers of the stratum spinosum of the marginal region of the psoriatic lesions, but not in the central area of the lesions. TIG2 expression was significantly lower in the basal layers of the central area of the paoriasis than that in the normal skin and uninvolved tissues (P < 0.01), and also lower in the marginal regions of the lesions (P < 0.01).The suprabasal layers of the marginal region in the lesion showed significantly lower TIG2 expression than the central area of the lesion (P < 0.01). CONCLUSION: TIG2 may maintain the normal differentiation of epidermal keratinocytes and implicate in the pathogenesis and development of psoriasis vulgaris.

[Synergistic effects of acitretin and narrow-band ultraviolet-B in inducing retinoic acid receptor gamma mRNA expression in normal human keratinocytes].

OBJECTIVE: To investigate the changes in cell proliferation and retinoic acid receptor gamma (RARgamma) mRNA expression in normal human keratinocytes after acitretin treatment and/or narrow-band ultraviolet-B irradiation. METHODS: Normal human keratinocytes were exposed to irradiation with 100 mJ/cm square NB-UVB and/or subsequent 12-hour incubation with 1x10(-6) mol/L acitretin, and the expression of RARgamma mRNA in the cells was examined using RT-PCR and real-time quantitative RT-PCR. RESULTS: A 0.9- and a 2.3-fold increase in RARgamma mRNA expression was induced in the cells by exposure to 100 mJ/cm square NB-UVB and 10(-6) mol/L acitretin, respectively, and the expression was synergistically enhanced by 2.8-fold after their combined treatment. CONCLUSION: Upregulated expression of RARgamma mRNA can be associated with keratinocyte growth inhibition after treatment with acitretin and NB-UVB irradiation.