Gene expression patterns and profile changes pre- and post-erlotinib treatment in patients with metastatic breast cancer.

PURPOSE: To delineate gene expression patterns and profile changes in metastatic tumor biopsies at baseline and 1 month after treatment with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib in patients with metastatic breast cancer. EXPERIMENTAL DESIGN: Patients were treated with 150 mg of oral erlotinib daily. Gene expression profiles were measured with Affymetrix U133A GeneChip and immunohistochemistry was used to validate microarray findings. RESULTS: Estrogen receptor (ER) status by immunohistochemistry is nearly coincided with the two major expression clusters determined by expression of genes using unsupervised hierarchical clustering analysis. One of 10 patients had an EGFR-positive tumor detected by both microarray and immunohistochemistry. In this tumor, tissue inhibitor of metalloproteinases-3 and collagen type 1 alpha 2, which are the EGF-down-regulated growth repressors, were significantly increased by erlotinib. Gene changes in EGFR-negative tumors are those of G-protein-linked and cell surface receptor-linked signaling. Gene ontology comparison analysis pretreatment and posttreatment in EGFR-negative tumors revealed biological process categories that have more genes differentially expressed than expected by chance. Among 495 gene ontology categories, the significant differed gene ontology groups include G-protein-coupled receptor protein signaling (34 genes, P = 0.002) and cell surface receptor-linked signal transduction (74 genes, P = 0.007). CONCLUSIONS: ER status reflects the major difference in gene expression pattern in metastatic breast cancer. Erlotinib had effects on genes of EGFR signaling pathway in the EGFR-positive tumor and on gene ontology biological process categories or genes that have function in signal transduction in EGFR-negative tumors.     

Persistent reversal of diabetes by transplantation of fetal pig proislets into nude mice

Facing the limited availability of human adult and fetal pancreases, fetal pig proislets (pancreatic islet precursors) were investigated in view of several inherent advantages. Six litters of fetuses of mean +/- SE gestational age 75 +/- 3 days were obtained from commercially available farm pigs. Pancreatic tissue was gently digested with collagenase, then a 10-day culture was performed. During culture, fetal proislets showed no insulin response to glucose alone but a significant response to glucose plus theophylline. The insulin content per microgram of DNA in the cultured proislets continuously increased. Histological examination by immunoperoxidase staining showed that, apart from single insulin- and glucagon-positive cells, there were no discrete islets in the pancreatic tissue and the cultured proislets. Diabetes was induced with streptozocin (STZ) in eight nude mice 3-4 wk after proislet transplantation and in another eight nude mice without transplantation. During the initial week, blood glucose levels of mice in both groups increased rapidly. The mean +/- SE peak value of blood glucose levels in the transplanted group was 20.4 +/- 2.0 mM and was 20.1 +/- 1.3 mM in the group without transplantation. Simultaneously, body weight decreased from 29.5 +/- 0.7 to 21.5 +/- 0.9 g and from 27.9 +/- 0.7 to 19 +/- 1 g in the groups, respectively. Afterward, blood glucose levels of mice in the transplanted group gradually decreased, and normoglycemia was achieved in all mice within 50 +/- 13 days after injection of STZ, i.e., 74 +/- 13 days after transplantation. The group without transplantation persistently maintained blood glucose levels greater than 16.7 mM.(ABSTRACT TRUNCATED AT 250 WORDS)     

Differential changes of retina dopamine binding sites and adenylyl cyclase responses following 6-hydroxydopamine treatment.

Both dopamine D1 and D2 receptors are present in rat retina. D1 receptors are positively coupled to adenylyl cyclase, while D2 receptors are negatively coupled. After intraocular administration of the neurotoxin 6-hydroxydopamine (6-OHDA) there is depletion of retinal dopamine by about 90%, as well as a decrease of the number of D1 and D2 receptor binding sites. Following the 6-OHDA lesion, there is an enhancement of the D1 receptor-stimulated accumulation of cyclic-AMP and a loss of D2 receptor-inhibited accumulation of cyclic-AMP. Our results suggest that some of the retinal D2 receptors are coupled to adenylyl cyclase and some are not.     

c-myc is required for osteoclast differentiation.

The role of the receptor activator of nuclear factor kappaB (NF-kappaB) ligand (RANKL)-a tumor necrosis factor (TNF)-related cytokine-in osteoclast formation has been established clearly. However, the downstream signaling pathways activated by this cytokine remain largely unknown. To identify genes that play a role in osteoclastogenesis, we used RAW 264.7 mouse monocytes as a model system for the differentiation of multinucleated osteoclasts from mononucleated precursors. RAW 264.7 cells were induced with RANKL to form multinucleated giant osteoclast-like cells (OCLs) that expressed a number of osteoclast-specific markers and were able to form resorption pits on both calcium phosphate films and bone slices. This system was used to identify genes that are regulated by RANKL and may play a role in osteoclast differentiation. The proto-oncogene c-myc was strongly up-regulated in RANKL-induced OCLs but was absent in undifferentiated cells. Expression of Myc partners Max and Mad, on the other hand, was constant during OCL differentiation. We expressed a dominant negative Myc in RAW 264.7 cells and were able to block RANKL-induced OCL formation. Northern Blot analysis revealed a delay and a significant reduction in the level of messenger RNA (mRNA) for tartrate-resistant acid phosphatase (TRAP) and cathepsin K. We conclude that c-myc is a downstream target of RANKL and its expression is required for RANKL-induced osteoclastogenesis.     

经颅彩色双功超声在脑血管疾病中的临床应用和进展

经颅彩色双功超声是一种新型、无创的超声诊断仪,高空间分辨率显示颅内血管和脑实质的结构,笔者查阅了近年来相关文献,主要综述经颅彩色多普勒血流显像在颅脑血管疾病中的诊断价值,同时讨论二维经颅超声的应用及新的实验性显像技术。     

重组人血小板源性生长因子增加细胞外信号调节激酶磷酸化促进糖尿病大鼠全层皮肤缺损创面愈合

目的 在体观察重组人血小板源性生长因子（recombinant human platelet—derived growth factor，rhPDGF）促进糖尿病大鼠全层皮肤缺损创面修复可能涉及的细胞和分子机制，研究其可能涉及的信号通路。方法 26只糖尿病大鼠，每只动物背部制备4个全层皮肤缺损创面，选取其中52个创面，随机分成3组，即对照组，创面自然愈合；rhPDGF治疗组，创面rhPDGF用量为7．0μg／cm^2；赋形剂组，创面用等量赋形剂凝胶。观察治疗后3、7和14d创面肉芽形成、胶原沉积、再上皮化速率以及炎性细胞浸润情况，并采用免疫荧光和免疫组织化学技术观察创面周围和创面修复细胞内细胞外信号调节激酶1／2（extracellular signal—regulated kinase1／2，ERK1／2）磷酸化和增殖细胞核抗原（proliferative cell nuclear antigen，PCNA）的表达。结果 组织学观察，rhPDGF治疗组创面可见大量炎性细胞浸润，毛细血管胚芽及成纤维细胞明显多于另两组（P〈0．05）；胶原沉积明显，肉芽组织生长活跃，创面收缩显著，与对照组比较差异有统计学意义（P〈0．05）。免疫学研究显示，应用rhPDGF7～14d后，rhPDGF治疗组ERK1／2明显强于对照组和赋形剂组（P〈0．05）；且损伤后3～7d rhPDGF治疗组修复细胞PCNA的表达明显高于对照组和赋形剂组（P〈0．05）。结论 rhPDGF促糖尿病大鼠刨面愈合的作用部分是通过ERK1／2信号通路的磷酸化来完成的。     

Isolated complete orbital infarction: a common carotid artery occlusion syndrome

When blood flow through the internal and external carotid arteries is completely interrupted by ipsilateral common carotid artery occlusion, the arterial orbital circulation may be more compromised than the brain supply. We studied a pure and extreme example of this situation in a patient who presented with acute orbital infarction, but no cerebral ischemia on clinical, CT and single-photon emission computerized tomography (SPECT) grounds. Ipsilateral blindness corresponded to retinal, choroidal and optic nerve infarction. The pattern of ophthalmoplegia, with relative sparing of adduction, was more compatible with a muscle than a nerve dysfunction, but a reactive dilated pupil, corneal anesthesia, and orbital pain suggested that the intraorbital branches of the ocular motor nerves and ophthalmic division of the trigeminal nerve were not spared. In addition, signs of widespread ocular ischemia were present. Sequential examinations documented the evolution pattern over 1 year. The absence of an orbital collateral supply from the contralateral external carotid and muscular cervical arteries systems, which contrasted with an adequate middle cerebral artery supply via the contralateral internal carotid artery, may explain this isolated and complete form of orbital ischemia due to common carotid artery occlusion.