Effects of Progesterone on the Growth Regulation in Classical Progesterone Receptor-negative Malignant Melanoma Cells / 华中科技大学学报（医学）（英德文版）

This study investigated the growth-regulating effects of progesterone(Prog)on nPR-negative malignant melanoma cells and the possible mechanisms.A375 and A875 cells were cultured and treated with Prog of different concentrations.For signal transduction pathway studies,the cells were pretreated with Prog receptor antagonist(RU486,1×10 7 mol/L)or MAPK inhibitor (U0126,5×10-6 mol/L)for 1 h and then co-incubated with prog(10-9 mol/L)for another 24 h.Indirect immunofluorescence assay,MTT,flow cytornetry and Western blotting were used for assessing the nPR expression,cell growth,cell apoptosis and ERK1/2 Phosphorylation,respectively.Our results showed that lower progesterone concentration promoted the proliferation of both A375 and A875 cells,but this growth-stimulatory effect decreased at progesterone concentration of 1 × 10-7mol/L or higher.The response could be abolished by MAPK inhibitor U0126,but could not be blocked by progesterone antagonist RU486.Flow cytometry exhibited that high concentration(≥1×10-7 mol/L)progesterone increased the apoptosis of the two cells in a dose-dependent manner.The level of ERK 1/2 phosphorylation was increased by a lower progesterone concentration,but reduced by a higber concentration(1×10-6 mol/L).These results suggest progesterone exerts growth-regulating effects on nPR-negative tumor cells through a non-genomic mechanism.

Selective Expression of Progesterone Receptor in Malignant Melanoma Was Inversely Correlated with PCNA / 华中科技大学学报（医学）（英德文版）

To investigate the role of progesterone receptor (PR) expression in malignant melanoma (MM), PR and proliferative cell nuclear antigen (PCNA) expression were immunohistochemistri- tally evaluated in a series of 35 specimens of MM, and the correlation between the immunohisto- chemistrical findings and clinicopathological data was also analyzed. PR expression was detected in 25.7% (9/35) of the patients with MM. No PR expression was observed in nevi. PR expression was inversely correlated with PCNA expression (r=-0.353, P=0.026). PR expression was slightly in- creased in females, subjects aged under 55 y, those with ulceration, non-acral subtype and diagnosis delay longer than 1 y, but the difference was not statistically significant. Selective expression of pro- gesterone receptor in malignant melanoma might be correlated with inhibited tumor growth.

Up-regulation of Human Leukocyte Antigen G Expression in Primary Cutaneous Malignant Melanoma Associated with Host-vs-tumor Immune Response / 华中科技大学学报（医学）（英德文版）

Human leukocyte antigen G (HLA-G) is one of the molecules implicated in immunotolerance. To investigate the role of HLA-G in primary cutaneous malignant melanoma (CMM), a series of 47 skin melanocytic lesions were immunohistochemicaily evaluated. The correlation between HLA-G expression and CMM clinicohistopahtologicai data and Bcl-2 expression was also analyzed.HLA-G expression was detected in a variety of cell types. No significant difference in HLA-G expression was observed between malignant and non-malignant melanocytic lesions. HLA-G expres- sion was significantly correlated with the inflammatory infiltration and Bel-2 expression, whereas no significant correlation with ulceration, tumor thickness, clinical stage, histopathologicai subtypes were observed. HLA-G expression may be the result of host immune reaction in tumor microenvi- ronment rather than a malignant feature of CMM.