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781.
We identified the platelet derived growth factor receptor (PDGFR) as a potential target in epithelial ovarian carcinoma (EOC). This led us to test whether inhibition of the PDGFR affects ovarian cancer cell proliferation and survival and regulates other processes critical to tumor growth and metastasis. We postulated that there is a correlation between the PDGF-PDGFR axis and the secretion of VEGF in EOC. VEGF secretion in ovarian tumors, cancer cells, serum and ascites fluid was measured by IHC, Western Blot and ELISA. We found increased VEGF expression and secretion in most ovarian tumors (by IHC), in EOC malignant ascites and in the conditioned media of primary ovarian cancer cells (quantified by ELISA). In malignant ascites, the levels of secreted PDGF BB and VEGF were strongly correlated (Pearson coefficient of correlation R = 0.728), suggesting that the two pathways interconnect. In PDGFR expressing immortalized ovarian cancer cells, PDGF potently induced VEGF secretion, while imatinib mesylate (Gleevec), a partially selective PDGFR inhibitor, reduced PDGF stimulated VEGF production to basal state. In ovarian cancer cells overexpressing constitutively active Akt, imatinib inhibited partially VEGF secretion, suggesting that the PI3K/Akt pathway is implicated in PDGF-stimulated VEGF secretion. In summary, these results suggest a correlation between the PDGF and VEGF networks in ovarian cancer cells and tumors. The effects of imatinib on VEGF secretion in tumor cells may affect the tumor microenvironment in a manner detrimental to tumor progression.  相似文献   
782.
2-methoxyestradiol (2ME2), an estradiol metabolite with antiproliferative and antiangiogenic activities, is in phase I/II clinical trials for breast cancer. 2ME2 inhibits microtubule polymerization and causes cells to arrest in G2-M. The purpose of this study was to further elucidate the molecular mechanism of 2ME2. MDA-MB-435 breast cancer cells were treated with 2ME2 (2 micromol/L) or vehicle alone. RNA was extracted and genomic profiling was done using 22k Agilent microarrays. Expression Analysis Systematic Explorer was used to determine enrichment of Gene Ontology categories. Protein isolates were subjected to Western blot analysis. Protein synthesis was measured with a [35S]methionine pulse assay. An MDA-MB-435 cell line with two beta-tubulin mutations (2ME2R) was used to determine whether novel mechanisms were tubulin-dependent. Gene Ontology categories enriched include genes that regulate the mitotic spindle assembly checkpoint, apoptosis, and the cytosolic ribosome. The target of the mitotic spindle assembly checkpoint is the anaphase-promoting complex (APC). APC inhibition was confirmed by measuring protein levels of its targets securin and cyclin B1, which were increased in 2ME2-treated cells. Because gene expression in the cytosolic ribosome category was decreased, we evaluated whether 2ME2 decreases protein translation. This was confirmed with a pulse assay, which showed decreased isotope incorporation in 2ME2-treated cells, which was maintained in the tubulin-resistant 2ME2R cells. APC inhibition was not maintained in 2ME2R cells. 2ME2 induces tubulin-dependent cell cycle arrest through regulation of genes involved in the mitotic spindle assembly checkpoint, which results in inhibition of the APC and tubulin-independent inhibition of protein translation.  相似文献   
783.
This post hoc analysis of MONARCH 2 and MONARCH 3 assesses the efficacy, safety, and pharmacokinetics (PK) of abemaciclib in combination with endocrine therapy (ET) in East Asian patients with hormone receptor positive (HR+), human epidermal growth factor receptor 2-negative (HER2−) advanced breast cancer. MONARCH 2 and MONARCH 3 are global, randomized, double-blind, phase 3 studies of abemaciclib/placebo + fulvestrant and abemaciclib/placebo + nonsteroidal aromatase inhibitor (NSAI, anastrozole or letrozole), respectively. The East Asian population comprised 212 (31.7%) of the 669 intent-to-treat (ITT) population in the MONARCH 2 trial and 144 (29.2%) of the 493 ITT patients in the MONARCH 3 trial. In the East Asian population, median progression-free survival (PFS) was significantly prolonged in the abemaciclib arm compared with placebo in both MONARCH 2 (hazard ratio [HR], 0.520; 95% confidence interval [CI], 0.362 to 0.747; P < .001; median: 21.2 vs 11.6 months) and MONARCH 3 (HR, 0.326; 95% CI, 0.200 to 0.531, P < .001; median: not reached vs 12.82 months). Diarrhea (MONARCH 2: 90%; MONARCH 3: 88%) and neutropenia (MONARCH 2: 68%; MONARCH 3: 58%) were the most frequent adverse events observed in the East Asian populations. Abemaciclib exposures and PK were similar in East Asians and the non-East Asian populations of both trials. Abemaciclib in combination with ET in the East Asian populations of MONARCH 2 and MONARCH 3 provided consistent results with the ITT populations, demonstrating improvements in efficacy with generally tolerable safety profiles for patients with HR+, HER2− advanced breast cancer.  相似文献   
784.
785.
PurposeTo study the retinal nerve fiber layer (RNFL) thickness and optic nerve head (ONH) parameters in obstructive sleep apnoea (OSA) patients and their relationship with severity of the disease.MethodsA cross-sectional, hospital-based study. Fifty-four OSA subjects and 54 controls were recruited. Candidate that fulfil the criteria with normal ocular examinations then proceed with spectrum domain Cirrus optical coherence tomography examinations. ONH parameters and RNFL thickness were evaluated. Apnoea-hypopnoea index (AHI) of the OSA group were obtained from the medical record.ResultsIn OSA, mean of average RNFL thickness was 93.87 μm, standard deviation (SD) = 9.17, p = 0.008 (p < 0.05) while superior RNFL thickness was 113.59 μm, SD = 16.29, p ≤ 0.001 (p < 0.05). RNFL thickness fairly correlate with severity of the disease (AHI), superior RNFL with R = 0.293, R2 = 0.087, p = 0.030 (p < 0.05), and nasal RNFL R = 0.292, R2 = 0.085, p = 0.032. No significant difference and correlation observed on ONH parameters. In control group, mean of average RNFL thickness was 98.96 μm, SD = 10.50, p = 0.008 (p < 0.05) while superior RNFL thickness was 125.76 μm, SD = 14.93, p ≤ 0.001 (p < 0.05).ConclusionsThe mean of the average and superior RNFL thickness were significantly lower in the OSA group compare to control. Regression analysis showed RNFL thickness having significantly linear relationship with the AHI, specifically involving the superior and nasal quadrant.  相似文献   
786.
PURPOSE: Maintenance of telomeres by telomerase is critical for the continuing proliferation of most advanced cancer cells. Telomerase activity has been detected in the vast majority of cancer cells but not most normal cells, making the enzyme an attractive target for anticancer therapy. The aim of this study was to address the breast cancer translational potential of the novel telomerase inhibitor, GRN163L. EXPERIMENTAL DESIGN: In the present study, we investigated the effects of GRN163L treatment on a panel of breast cancer cells representing different tumor subtypes with varying genetic backgrounds, including ER+, ER-, HER2+, BRCA1 mutant breast tumor cells as well as doxorubicin-resistant cancer cells. To investigate the in vivo effects of GRN163L, we employed a breast cancer xenograft and metastasis model that simulates a clinical situation in which a patient arrives with a primary tumor that may be then treated or surgically removed. RESULTS: GRN163L effectively inhibited telomerase activity in a dose-dependent fashion in all breast cancer cell lines resulting in progressive telomere shortening. A mismatch control oligonucleotide showed no effect on telomerase activity and GRN163L did not significantly affect telomere shortening in normal human mammary epithelial cells or in endothelial cells. Breast cancer cells that exhibited telomerase inhibition also exhibited significant reduction in colony formation and tumorigenicity. Furthermore, GRN163L suppressed tumor growth and lung metastases (P = 0.017) of MDA-MB-231 cells in vivo after 4 weeks of treatment. CONCLUSIONS: These results show in vivo effectiveness of GRN163L in breast cancer and support its promising clinical potential for breast cancer treatment.  相似文献   
787.
What separates a malignant from a normal cell? This question has occupied scientists for decades. Although a simple answer remains elusive, several hallmarks of malignancy have been identified. These critical features include uncontrolled proliferation, insensitivity to negative growth regulation, evasion of apoptosis, lack of senescence, invasion and metastasis, angiogenesis and genomic elasticity. Existing therapies predominantly target proliferation either with cytotoxic agents, ionising radiation or more targeted attacks on growth factor signalling pathways. Our most successful therapies to date inhibit proliferation via the oestrogen receptor (ER) and HER2 pathways. Further improvements in therapy must attack the other hallmarks of malignancy and will undoubtedly be accompanied by a better means of individual patient selection for such therapies. Indeed, each of these hallmarks presents a therapeutic opportunity. To believe otherwise would be to assume that a feature is both biologically crucial, yet therapeutically unimportant, an unlikely paradox. Here, we suggest the hallmarks of malignancy as a conceptual framework for understanding novel breast cancer therapies.  相似文献   
788.
To explore how red cell transfusions were used to support patients who underwent primary and revision hip and knee replacements classified within diagnosis-related group (DRG) 209 (major joint and limb reattachment procedures), we studied abstracted patient discharge records from 151 United States hospitals in 1986. A total of 9684 units of whole blood and/or separated red cells was used to support 6472 patients. The transfusion use varied by surgical procedure, with patient gender as an influencing factor. Large proportions of patients underwent surgery without requiring transfusion. Among transfused patients, the majority received 1 to 3 units of red cells; however, a minority of patients required multiple transfusions, thereby utilizing a disproportionate share of the blood resource. Comparison of transfusion practice within the seven most active hospitals revealed significant differences (p less than or equal to 0.01) in the percentage of patients actually transfused, but not in the mean number of units of red cell components transfused per transfused patient. Similar findings emerged from comparison of transfusion practice when all hospitals were segregated into five hospital classes on the basis of orthopedic surgical service activity. These effects were seen for both total knee and total hip replacement procedures. It can be concluded that the lack of clearly defined criteria for transfusion contributed to the variations observed.  相似文献   
789.

Background  

There is a growing interest to use health status or disease control questionnaires in routine clinical practice. However, the validity of most questionnaires is established using techniques developed for group level validation. This study examines a new method, using patient interviews, to validate a short health status questionnaire, the Clinical COPD Questionnaire (CCQ), at the individual patient level.  相似文献   
790.
部分纯化的大鼠肝脏蛋白激酶C和蛋白激酶A,在体外与棉酚的旋光异构体分别温育,结果(--)棉酚和(+)棉酚对蛋白激酶C活力均有剂量依赖性的抑制作用;(-)棉酚对Ⅰ型蛋白激酶A活力的抑制作用明显比(+)棉酚强,而(-)棉酚和(+)棉酚在高浓度时对Ⅱ型蛋白激酶A才显示抑制作用。结果提示棉酚在体内可能干扰细胞信息的传递过程。  相似文献   
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