BACKGROUND: This study examined the clinical significance of CCNE1 (Cyclin E1) amplification and assessed whether CCNE1 is a potential therapeutic target in ovarian cancer. METHODS: CCNE1 expression and amplification in ovarian cancer was assessed by immunohistochemistry, fluorescence in situ hybridization and clinical data collected by retrospective chart review. CCNE1 gene knockdown using silencing RNA and a CCNE1 gene transfection system were used to asses CCNE1 function in tissue samples of ovarian cancer. RESULTS: Gene amplification was identified in 18 (20.4%) of 88 ovarian carcinomas. CCNE1 copy number significantly correlated with CCNE1 protein expression (r ¼ 0.522, P < .0001). CCNE1 amplification significantly correlated with shorter disease-free survival and overall survival (P < .001). There were nonsignificant trends between high protein expression and poor disease-free survival (P ¼ .2865) and overall survival (P ¼ .1248). Multivariate analysis showed gene amplification was an independent prognostic factor for disease-free survival and overall survival after standard platinum-taxane chemotherapy (P ¼ .0274, P ¼ .0023). Profound growth inhibition and apoptosis were observed in silencing RNA-treated cancer cells with gene amplification compared with results in cancer cells with CCNE1 moderate expression without gene amplification or with low CCNE1 expression. CCNE1 overexpression stimulated proliferation in ovarian cancer cell lines ES2 and TOV-21G, which have lower endogenous CCNE1 expression. CONCLUSIONS: These findings indicate that CCNE1 overexpression is critical to growth and survival of ovarian cancer tumors with CCNE1 gene amplification. Furthermore, they suggest that CCNE1 silencing RNA-induced phenotypes depend on amplification status of ovarian cancers. Therefore, CCNE1-targeted therapy may benefit ovarian cancer patients with CCNE1 amplification.

Recently, the ARID1A gene has been identified as a novel tumor suppressor in ovarian clear cell carcinoma. The prognostic significance of the loss of ARID1A expression is not known. The current study was designed to evaluate whether ARID1A was a prognostic factor for progression, survival, and chemoresistance in ovarian clear cell carcinoma. A total of 60 patients, who were surgically treated for primary ovarian clear cell adenocarcinoma, were enrolled. Surgical specimens were examined for ARID1A protein expression by immunohistochemistry. The correlations between the loss of ARID1A expression and clinicopathological characteristics, prognosis, and chemosensitivity were investigated. Loss of ARID1A expression was identified in 9 (15.0%) of 60 ovarian clear cell carcinoma samples. Loss of ARID1A staining intensity (0 þ ) was more frequently found in cells of clear cell carcinomas than in high-grade serous carcinomas (Po0.01). Loss of ARID1A expression was significantly correlated with advanced FIGO stage and high CA125 levels (P ¼ 0.02, 0.01). There were no significant correlations between loss of ARID1A expression and patient age, status of residual tumor, Ki-67 labeling index, or the status of endometriosis. Loss of ARID1A correlated with shorter progression-free survival of patients with clear cell carcinomas treated with platinum-based chemotherapy (Po0.01). Loss of ARID1A expression tended to correlate with shorter overall survival in patients with ovarian clear cell carcinomas treated with platinum-based chemotherapy. When data were stratified for the multivariate analysis, only the loss of ARID1A expression remained a significant (P ¼ 0.03) predictor of reduced progressionfree survival. Of the 60 patients with ovarian clear cell carcinomas, 14 patients had measurable residual tumor after primary cytoreductive surgery. Tumors with loss of ARID1A expression were more likely to be chemoresistant than tumors with positive ARID1A expression (100.0 vs 40.0%, P ¼ 0.04). This study demonstrates that loss of ARID1A in ovarian clear cell carcinoma is a negative prognostic factor in patients treated with platinum-based chemotherapy. Measurement of ARID1A expression may be a method to predict resistance to platinum-based chemotherapy in patients with ovarian clear cell carcinoma.

Poly(lactic acid) (PLA) blended with poly (butylene succinate) (PBS) was prepared in the presence of lysine triisocyanate (LTI) by using a twin-screw extruder and injection molding machine. The physical properties, rheological behavior, compatibility, and morphology were investigated by using a tensile test, a Charpy impact test, melt mass-flow rate (MFR) measurements, size exclusion chromatography (SEC), and laser scanning confocal microscopy (LSCM). The impact strength of PLA/PBS(90/10 wt %) blend composite was about 18 kJ/m 2 in the absence of LTI, and it increased to 50-70 kJ/m 2 in the presence of LTI at 0.5 wt %. The MFR value of PLA/PBS(90/10 wt %) decreased from 25 g/10 min at 2008C in the absence of LTI to approximately 3 g/10 min in the presence of LTI. These results imply that isocyanate groups of LTI reacted with both terminal hydroxyl or carboxyl groups of the polymers. Spherical particles at 1 mm were observed by using LSCM in the presence of LTI. These results indicate that the LTI is a useful reactive processing agent to increase the compatibility of PLA/PBS blend composites to increase the impact strength of PLA.

To ascertain the minimal structural requirements for formation of the subunit and core light-harvesting complex (LH1), the alpha- and beta-polypeptides of the LH1 from three purple photosynthetic bacteria were enzymatically or chemically truncated or modified. These polypeptides were then used in reconstitution experiments with bacteriochlorophyll a (BChla), and the formation of subunit and LH1 complexes was evaluated using absorbance and circular dichroism spectroscopies. Truncation or modification outside of the conserved core sequence region of the polypeptides had no effect on subunit or LH1 formation. However, the extent of formation and stability of the subunit and LH1 decreased as the polypeptide was shortened inside the core region within the N-terminal domain. This behavior was suggested to be due to the loss of potential ion-pairing and/or hydrogen-bonding interactions between the polypeptides. While the spectroscopic properties of the subunit complexes generated using truncated polypeptides were analogous to those obtained using native polypeptides, in some cases the resulting LH1 complex absorption was blue-shifted relative to the control. Thus, truncation within the N-terminal domain may have long-range effects on the immediate BChla binding environment, since the putative BChla binding site resides near the C-terminal end of the polypeptides. It was also demonstrated that the His located within the membrane-spanning domain on the N-terminal end of the beta-polypeptide is not participating in ligation of the BChla in the reconstituted subunit and therefore probably not in LH1.

Poly(lactic acid) (PLA) blended with poly(e-caprolactone) (PCL) was prepared with various reactive processing agents. Four isocyanates-lysine triisocyanate (LTI); lysine diisocyanate (LDI); 1,3,5-tris(6-isocyanatohexyl)-1,3,5-triazinane-2,4,6-trione (Duranate TPA-100); 1,3,5-tris(6-isocyanatohexyl)biuret (Duranate 24A-100)and an industrial epoxide-trimethylolpropane triglycidyl ether (Epiclon 725)-were used as reactive processing agents. PLA/PCL blended in the presence of LTI had the highest torque in a mixer test. The test specimens were prepared by injection molding. The mechanical properties, thermal properties, molecular weight, melt viscosity, phase behavior, and morphology were investigated using tensile strength, impact strength, differential scanning calorimetry, melt mass-flow rate measurements, capillary rheometery, gel permeation chromatography, laser scanning confocal microscopy (LSCM), and visco-elasticity atomic force microscopy (VE-AFM). The impact strength increased considerably at 20 wt% PCL. The nominal tensile strain of PLA/PCL blended with LTI increased by 270%. The MFR values of PLA/PCL blends decreased with increasing LTI. Similar results were observed for shear viscosity. LSCM measurements showed that the diameters of PCL were dispersed about 0.4 lm in the presence of LTI. VE-AFM showed that spherical particles with diameters of 50 nm were PCL-rich domain. These results indicate that isocyanate groups of LTI react with both terminal hydroxyl or carboxyl groups of polymers, and the compatibility of PLA/PCL blends improves with LTI by reactive processing.