Inhibition of SKP2 Sensitizes Bromocriptine-Induced Apoptosis in Human Prolactinoma Cells / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Prolactinoma (prolactin-secreting pituitary adenoma) is one of the most common estrogen-related functional pituitary tumors. As an agonist of the dopamine D2 receptor, bromocriptine is used widely to inhibit prolactinoma progression. On the other hand, it is not always effective in clinical application. Although a dopamine D2 receptor deficiency contributes to the impaired efficiency of bromocriptine therapy to some extent, it is unknown whether there some other underlying mechanisms leading to bromocriptine resistance in prolactinoma treatment. That is the main point addressed in this project. MATERIALS AND METHODS: Human prolactinoma samples were used to analyze the S-phase kinase associated protein 2 (SKP2) expression level. Nutlin-3/adriamycin/cisplatin-treated GH3 and MMQ cells were used to analyze apoptosis in SKP2 overexpression or knockdown cells. SKP2 expression and the interaction partners of SKP2 were also detected after a bromocriptine treatment in 293T. Apoptosis was analyzed in C25 and bromocriptine-treated GH3 cells. RESULTS: Compared to normal pituitary samples, most prolactinoma samples exhibit higher levels of SKP2 expression, which could inhibit apoptosis in a p53-dependent manner. In addition, the bromocriptine treatment prolonged the half-life of SKP2 and resulted in SKP2 overexpression to a greater extent, which in turn compromised its pro-apoptotic effect. As a result, the bromocriptine treatment combined with C25 (a SKP2 inhibitor) led to the maximal apoptosis of human prolactinoma cells. CONCLUSION: These findings indicated that SKP2 inhibition sensitized the prolactinoma cells to bromocriptine and helped promote apoptosis. Moreover, a combined treatment of bromocriptine and C25 may contribute to the maximal apoptosis of human prolactinoma cells.

Neuroprotective effect of histone deacetylases inhibitor MS-275 following traumatic brain injury in rats / 中华创伤杂志

Objective To evaluate the neuroprotective benefits of histone deacetylases (HDAC)inhibitor MS-275 in rats with moderate traumatic brain injury (TBI).Methods Sixty-eight adult male SD rats were assigned to sham injury + placebo treatment (control group),TBI + placebo treatment (injury group),TBI + MS-275 (15 mg/kg) treatment (treatment group Ⅰ) and TBI + MS-275 (45 mg/kg)treatment (treatment group Ⅱ) according to the random number table.An experimental model of moderate TBI in the rat was induced using a lateral fluid percussion device.MS-275 was dissolved in DMSO and administered (15 and 45 mg/kg) intraperitoneally in seven consecutive days(once a day).The first administration was done in 30 minutes postinjury.Alteration in body weight of rats in each group was recorded after injury.Spatial learning and memory retention in rats was assessed using the Morris Water Maze in days 10-14 after TBI.Brain tissues were sectioned to measure acetyl-histone H3 and neuronal survivals in the hippocampus CA2-3 region using immunohistochemistry and cresyl-violet staining techniques.Results TBI rats showed significant body weight loss in 3 days postinjury as compared with the controls (P ＜0.05) and then gradually gained the body weight in 4-5 days postinjury.No significant difference in actual body weight loss after injury was found among injury group and treatment groups (F =0.149,P ＞0.05).Behavioral result revealed that the animals in treatment groups had significant improvement in cognitive performance as compared with injury group (P ＜ 0.01).Immunohistochemical results presented a markedly increased level of acetyl-histone H3 in both treatment groups,with no significant difference as compared with control group and a trend of increase in the survived neurons in the CA2-3 hippocampus in 14 days postinjury (P ＞ 0.05).Conclusions MS-275 achieves visible improvement of acetyl-histone H3 level and cognitive performance in the acute phase of TBI.Simultaneously,this treatment has an ameliorative effect on pathological changes associated with TBI as well and provides a neuroprotective effect against TBI.

Cloning, expression and purification of novel gene NBEAL1 and its relationship with pathological grades of glioma / 中国肿瘤生物治疗杂志

Objective: To construct the expression plasmid of a novel gene human NBEAL1 (neurobeachin like 1), and to study its relationship with the pathological grades of glioma. Methods: Total RNA of human glioma cell line U251 was extracted. NBEAL1 expression plasmid pGEX-KG/NBEAL1 was constructed and transferred into E. coli BL21. Recombinant NBEAL1 protein was induced by IPTG and further purified by GST affinity chromatographic column. The purity of recombinant NBEAL1 protein was examined by Western blotting analysis. A NBEAL1 protein specific monoclonal antibody was prepared and was used to study the relationship of NBEAL1 expression with pathological grades of glioma. Results: The NBEAL1 gene fragment was successfully cloned into pGEX-KG expression plasmid and verified by DNA sequencing. The recombinant NBEAL1 protein was expressed in inclusion bodies, with a yield of more than 30% of total bacterial proteins; the purity of purified NBEAL1 protein was above 95%. Western blotting analysis confirmed that the purified protein containing GST tag and NBEAL protein. NBEAL1 protein was lowly expressed in normal brain tissues and highly expressed in low grade glioma tissues; and the expression of NBEAL1 decreased with the increase of glioma malignancy. Conclusion: The NBEAL1 protein has been successfully cloned, expressed and purified. NBEAL1 protein expression in glioma tissues is negatively associated with the pathological grades of glioma.

Development of the sphenoid sinus affects the surgical approach via saddle area / 第二军医大学学报

Objective: : To investigate whether development of the sph e noid sinus affect the surgical approach via saddle area. Methods: The pneumatization of sphenoid sinus of 50 cadaver heads was studied through t hinner CT scanning of coronal, sagittal and axial position. The sphenoid sinus w as classified according to the degree of pneumatization of sphenoid sinus toward s sphenoid bone, small wing of sphenoid bone and epippium. Results: There were 4% conchal, 18% pre-sellar, 18% semi-sellar, 14% sellar, 46% sellar -occipital in 100 sphenoid sinus cases. The transversal diameter of left and ri ght was 18.48 mm and 17.58 mm; The sagittal diameter of left and right was 2 2.20 mm and 20.82 mm, The vertical diameter of left and right was 21.02 mm and 2 0.38 mm. The distance between centre track and the later wall of sphenoid sinus was 14.78 mm in left side and 15.18 mm in right side. Conclusion: Thinner CT scanning with coronal and sagittal position can clearly show pneum atization of sphenoid sinus on both sides. Different pneumatization of sphenoid sinus provide anatomical basis for choosing operation approach.