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1.
Tang L  Zhao X 《Medical hypotheses》2011,76(4):530-532
Currently, surgery plus adjuvant chemotherapy are the mainstay of care in the treatment of ovarian cancer. Although this therapeutic strategy has been considered as "golden standard" regimen with profound impact on survival improvement, several obstacles have been encountered, such as chemotherapy drug resistance and disease relapse. Residual cancer cells in the abdominal cavity and vessels are considered as the main cause of disease relapse. New treatment options attempt to yield higher survival rate in patients. Monoclonal antibodies such as Trastuzumab and Cetuximab showed promising effects on several solid tumors. But for epithelial ovarian cancer, modalities of intravenous monoclonal antibody monotherapy have not achieved expected results as they have in the treatments of breast and colorectal cancer. Relatively low expression of matched receptors on ovarian cancer cells, as well as the intravenous delivery with less efficacy of intra-abdominal antibody accumulation, may account for lack of efficacy of monoclonal antibody on ovarian cancer. So we hypothesize that polyvalent antibodies boosted from rabbit by inoculating human tumor cells could deplete ovarian cancer cells through intraperitoneal route. The mechanisms may include interrupting ligand-receptor binding and thus result in blockage of intracellular signaling pathways such as EGFR and HER2 signal transduction, and possibly may also involve antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity.  相似文献   

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Positive emotional states have been shown to confer resilience to depression and anxiety in humans, but the molecular mechanisms underlying these effects have not yet been elucidated. In laboratory rats, positive emotional states can be measured by 50-kHz ultrasonic vocalizations (hedonic USVs), which are maximally elicited by juvenile rough-and-tumble play behavior. Using a focused microarray platform, insulin-like growth factor I (IGFI) extracellular signaling genes were found to be upregulated by hedonic rough-and-tumble play but not depressogenic social defeat. Administration of IGFI into the lateral ventricle increased rates of hedonic USVs in an IGFI receptor (IGFIR)-dependent manner. Lateral ventricle infusions of an siRNA specific to the IGFIR decreased rates of hedonic 50-kHz USVs. These results show that IGFI plays a functional role in the generation of positive affective states and that IGFI-dependent signaling is a potential therapeutic target for the treatment of depression and anxiety.  相似文献   

4.
The oral contraceptive pill is associated with a modest increase in the risk of early-onset breast cancer in the general population, but it is possible that the risk is higher in certain subgroups of women. The relative risk of breast cancer associated with oral contraceptive use has been reported to be higher for African-American women than for white women. African-American women also have a higher incidence of premenopausal breast cancer than white women. Circulating levels of insulin-like growth factor-1 (IGF-I) vary between ethnic groups and are positively associated with the risk of premenopausal breast cancer. In general, the plasma level of IGF-I is lower in women who take oral contraceptives than in women who do not. In an attempt to explain the observed ethnic difference in IGF-I levels with oral contraceptive use, we sought to identify polymorphic variants of genes that are associated with IGF-I levels and estrogen metabolism. We measured IGF-I and IGFBP-3 plasma levels in 503 nulligravid women between the ages of 17 and 35. All women filled out a questionnaire that included information about ethnic background and oral contraceptive use. Samples of DNA were used to genotype the women for known polymorphic variants in the IGF1, AIB1, and CYP3A4 genes. Black women had significantly higher mean IGF-I levels than white women (330 ng/ml versus 284 ng/ml; P = 0.001, adjusted for age and oral contraceptive use). IGF-I levels were significantly suppressed by oral contraceptives in white women (301 ng/ml versus 267 ng/ml; P = 0.0003), but not in black women. Among oral contraceptive users, the IGF-I level was positively associated with the absence of the IGF1 19-repeat allele (338 ng/ml versus 265 ng/ml; P = 0.00007), with the presence of the CYP3A4 variant allele (320 ng/ml versus 269 ng/ml; P = 0.01), and with the presence of the AIB1 26-repeat allele (291 ng/ml versus 271; P = 0.08). After adjusting for genotypes, ethnic group was no longer a significant predictor of the IGF-I level. IGF-I levels are higher among black than white women. Polymorphic variants in the CYP3A4, IGF1, and AIB1 genes are associated with increases in the plasma levels of IGF-I among oral contraceptive users and the variant alleles are much more common in black women than in white women. The high incidence of premenopausal breast cancer among black women may be mediated through genetic modifiers of circulating levels of IGF-I.  相似文献   

5.
Genomic imprinting is defined as a gamete-specific modification causing differential expression of the two alleles of a gene in somatic cells and is becoming increasingly recognized as playing an important role in a number of human diseases including cancer. We have reported that the loss of the insulin-like growth factor-2 (IGF2) gene imprinting results in the deregulation of both IGF2 alleles, which may contribute to the onset of Wilms tumor. It is important to see whether such abnormal genomic imprinting is implicated in the etiology of common adulthood cancers. In the present study we have examined the expression level and imprinting status of the IGF2 gene in human ovaries and ovarian cancers. We confirm that IGF2 is significantly expressed in ovaries and ovarian cancers. In normal ovaries, both surface epithelium and the ovary proper demonstrate monoallelic IGF2 expression. Among 27 tumors, all 11 heterozygous for the IGF2 locus show monoallelic IGF2 expression (2 of them are proven to be from the paternal allele). The data suggest that the increased IGF2 gene expression in ovarian cancer may be achieved by a mechanism other than loss of imprinting.  相似文献   

6.
The role of the insulin-like growth factor system in prenatal growth   总被引:3,自引:0,他引:3  
Fetal growth is a complex process involving multiple environmental and genetic factors. Fetal growth restriction is associated with morbidity among small for gestational age (SGA) neonates as well as in children and adults who are former SGA infants. Over the last decade it has been recognized that the insulin-like growth factor axis has a critical role in mediating fetal and postnatal growth. However, how these hormones are involved in common pathological processes, leading to fetal growth restriction (FGR), remains unknown. In humans and mice, mutations or targeted deletions of the IGF ligands IGF1 and IGF2, as well as the IGF type-I receptor and its main signaling molecule IRS1 lead to FGR. IGFs are low in human SGA newborns; however, only a small minority of these infants have mutations of IGF-related molecules, rather, idiopathic or maternal factors are thought to induce FGR in most of these cases. Fetal growth is complex process governed by multiple genetic factors, but ultimately influenced by environmental processes, chief among them being nutrient supply from the mother to the placenta and from the placenta to the fetus. Understanding the molecular processes by which maternal factors contribute to fetal growth is an important step in developing strategies for diagnosing and treating different variants of fetal growth retardation. As our knowledge of these mechanisms become more sophisticated, we may find that many "idiopathic" cases of IUGR are also caused by subtle alterations in the IGF axis including heterozygotic mutations, polymorphisms, and epigenetic regulation.  相似文献   

7.
Vitamin D is known to be widely deficient in Western populations. The implications of this in terms of bone health are increasingly understood, yet its impact on other health areas, particularly mental health, is unclear. Recent data suggests that hypovitaminosis D may be common, especially in the elderly. Other studies have suggested that low levels of vitamin D are associated with poor mood. There are a number of trials that have suggested a role for Vitamin D in the supplementary treatment of depression. Dose may be a critical issue, as sun exposure and dietary intake may be low and high doses may be required.  相似文献   

8.
Insulin-like growth factor binding protein 2 (IGFBP2) is involved in the progression of many epithelial cancers. However, its role in non-small cell lung cancer (NSCLC), another type of epithelial cancer, remains unclear. We detected IGFBP2 expression using immunohistochemistry in surgically resected tumors from 110 NSCLC patients, 37 of which had metastases. The positive rate of IGFBP2 expression was compared between the metastatic and the non-metastatic group, and correlations of IGFBP2 expression with metastasis and overall survival were analyzed. We also investigated the expression of IGFBP2 in microvesicles (MVs) collected from primary lung cancer cell cultures, and in different locations of newly resected NSCLC tumors, using immunoblotting. The overall positive rate of IGFBP2 expression in lung cancer was 51.8 % and it was significantly higher in the metastatic group than in the non-metastatic group (70.3 and 42.5 % respectively, p < 0.01). And the higher the lymph node stage, the higher the positive rate. Cytoplasmic expression was predominant in the majority of the tumors. Based on multivariate regression analysis, IGFBP2 was correlated with metastasis and poor overall survival (Hazard ratio: 3.56 and 3.23 respectively). IGFBP2 was detectable in the MVs collected from IGFBP2 positive cell lines, and its expression was most abundant in the marginal region of the newly resected tumors. IGFBP2 is associated with metastasis and poor survival of lung cancer. Its presence in MVs and high abundance in the marginal region of tumors suggest that its association with metastasis may be related to tumor microenviroment remodeling in NSCLC.  相似文献   

9.
大肠癌中胰岛素样生长因子2基因的印迹状态和表达   总被引:9,自引:2,他引:9  
目的:研究胰岛素样生长因子2(insulin-like growth factor 2,IGF2)基因的印迹状态和表达与大肠癌的关系,为研究大肠癌的发生机理提供线索。方法:用逆转录-聚合酶链反应半定量检测IGF2的表达量,比较其在大肠癌及癌旁组织中有无差异,用限制性片段长度多态检测IGF2的印迹状态,分析印迹状态、表达量与大肠癌的关系。结果:82.4%(28/34)大肠癌有IGF2的表达增加,IGF2的表达量在肿瘤组织与癌旁组织中差异有显著性(P<0.01,t=3.01)。IGF2在87.5%(14/16)大肠癌组织中发生了印迹丢失,但其相对应的癌旁组织也有71.4%(10/14)存在IGF2的印迹丢失。结论:IGF2的表达增加是大肠癌发生的相关因素,IGF2的印迹丢失可能是大肠癌发生的前期表现。  相似文献   

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11.
Loss of genomic imprinting is an epigenetic alteration of some cancers involving the absence of parental origin–specific expression of imprinted genes. Loss of genomic imprinting of insulin-like growth factor II is often detected in colorectal cancer. However, the genetic alterations accompanied by colorectal cancer with insulin-like growth factor II loss of genomic imprinting have not been fully determined. Genomic DNA samples were collected from 52 colorectal cancer tissues and analyzed. The loss of insulin-like growth factor II genomic imprinting status was determined by assessing the demethylation of the insulin-like growth factor II differentially methylated region using bisulfite sequencing. The molecular signatures were also examined: genetic mutations of KRAS, BRAF, and PIK3CA; the expression of CTNNB1 and TP53; and microsatellite instability status. Several cases of colorectal cancer with normal insulin-like growth factor II imprinting were located in the distal colon; in contrast, colorectal cancer with loss of genomic imprinting tended to be found in the proximal colon (22.7 versus 56.6%). The PIK3CA gene mutation was highly detected in normal imprinting tumors compared to colorectal cancers with insulin-like growth factor II loss of genomic imprinting (27.3% versus 6.7%). In multivariate analysis of these clinicopathologic and molecular factors of tumors, statistically significant relationships were observed among the proximal location of the tumor (odds ratio, 12.9; 95% confidence interval, 1.52-110.13), PIK3CA genetic mutation (odds ratio, 0.082; 95% confidence interval, 0.01-0.73), and insulin-like growth factor II genomic imprinting status. Our findings indicate that colorectal cancers with demethylation of the insulin-like growth factor II gene are distinct from normal imprinting tumors, both in clinical and genetic features.  相似文献   

12.
Peptide p3 may play a neuroprotective role in the brain   总被引:1,自引:0,他引:1  
Han W  Ji T  Mei B  Su J 《Medical hypotheses》2011,76(4):543-546
Alzheimer's disease (AD) is an age-related neurodegenerative disease. The amyloid-β (Aβ) peptide is considered a major etiological factor in the development of AD. BACE1-deficient mice and forebrain-specific conditional presenilin1 and presenilin2 double knockout mice (presenilins cDKO mice) both lack Aβ, but exhibit completely different phenotypes. The peptide p3 may play a neuroprotective role. A lack of peptide p3 could trigger an inflammatory response in the brain of presenilins cDKO mice.  相似文献   

13.
Epidemiological studies demonstrated that even in the absence of other risk factors (e.g., diabetes, hypertension, hypercholesterolemia), vascular aging significantly increases cardiovascular morbidity. Previous studies revealed that vascular aging is characterized by an age-dependent decline in endothelial function due to a decreased bioavailability of NO and increased production of reactive oxygen species. Yet, the mechanisms underlying the process of vascular aging are still poorly understood. Many authors consider that aging is a mitochondrial disease. Indeed, there is evidence that aging is associated with an increase in mtDNA damage and a decline in expression/activity of mitochondrial enzymes in various organs. On the basis of recent observations we predict that similar changes in mitochondrial gene expression profile are present in the aged cardiovascular system as well. It is significant, that components of the electron transport chain (including cytochrome c oxidase) seem to be similarly down-regulated with age in many species. Because pharmacological inhibition of mitochondrial energy metabolism significantly impairs endothelium-dependent vascular relaxation and may increase the production of reactive oxygen species, we propose that alterations of mitochondrial energetic phenotype may contribute to endothelial dysfunction in aging.  相似文献   

14.
Sarcoidosis is a granulomatous systemic disorder most often affecting the lung. Pulmonary fibrosis develops in approximately 10%-15% of patients with sarcoidosis. The human gene GREM1 encodes gremlin, a member of the bone morphogenetic protein antagonist family. Bone morphogenetic proteins are essential for the maintenance of tissue homeostasis and regeneration after injury. We examined associations between genetic variation in GREM1 and pulmonary disease outcome in patients with pulmonary sarcoidosis. Four common tag single nucleotide polymorphisms spanning GREM1 were genotyped in 483 controls and in 237 sarcoidosis patients with radiographic data at pulmonary disease outcome, defined by chest X-ray after a minimum of 4 years follow-up. Highly significant differences were found between GREM1 genotype frequencies in sarcoidosis patients without chest X-ray abnormalities (stage 0) (n = 116) versus patients who had fibrosis on chest X-ray (stage IV) (n = 59) at pulmonary disease outcome. The most significant association was with GREM1 rs1919364. The recessive model resulted in an increased risk of fibrosis development for homozygous carriers of the C allele at GREM1 rs1919364 versus carriers of the G allele [P = 9.3 × 10??, χ2 = 24.1, odds ratio (OR) = 6.37 (2.89-14.1)]. This study is the first to suggest that genetic variation of GREM1 predisposes to pulmonary fibrosis in sarcoidosis patients. Carriers of the GREM1 CC genotype at position rs1919364 were at 6.4 times greater risk for developing fibrosis.  相似文献   

15.
Hemangiopericytoma is a rare soft tissue tumor originating from contractile pericapillary pericytes. To address the issue of molecular genetic events that participate in genesis and progression of hemangiopericytoma we analyzed insulin-like growth factor (IGF) II and IGF I receptor in 29 tumors collected from a human tumor bank network. Seven of these tumors were associated with severe hypoglycemia; six were retroperitoneal and one was located in the leg. Of 22 tumors tested 12 (54.5%) exhibited IGF II mRNA, while almost 90% (17 of 19) of hemangiopericytomas exhibited IGF I receptor mRNA. Sera from some patients whose tumors expressed IGF II mRNA contained elevated levels of IGF II. Removal of the tumor eliminated most of the IGF II immunoreactivity from the sera. The potential role of IGF II as a growth-promoting factor was examined on three malignant primary hemangiopericytoma cell cultures. Extracellular addition of IGF II significantly enhanced cell proliferation in a dose-dependent manner. Antisense oligodeoxynucleotides that specifically inhibit IGF II mRNA, at a concentration of 40 or 80 micrograms/ml, inhibited the growth of hemangiopericytoma cells significantly, by 40%. Simultaneous administration of antisense deoxyoligonucleotides to both IGF II and IGF I receptor inhibited tumor cell proliferation by even 80%. Our data suggest that tumor cells produce IGF II, and that this in turn stimulates their proliferation by autocrine mechanisms.  相似文献   

16.
The human epidermal growth factor receptor (HER) family consists of four distinct receptors: HER1 (epidermal growth factor receptor), HER2, HER3, and HER4. Their specific activating ligands are collectively known as neuregulins (NRG). We hypothesized that one member of the NRG family, NRG-1, and the HER family would play a role in fetal lung development. To test this hypothesis, we defined NRG-1 and HER gene expression in mid-trimester human fetal lung tissue. HER2 and HER3 messenger RNA and protein were detected in the fetal lung, but HER4 expression was not detected. Immunohistochemical staining of fetal lung tissue localized HER2 and HER3 protein to the developing lung epithelium. NRG-1 expression was not found in freshly isolated human fetal lung, but it was observed in fetal lung explants after 2 d of explant culture. Immunohistochemistry of cultured human fetal lung explants revealed that NRG-1 protein was also expressed in pulmonary epithelial cells. Exposing human fetal lung to recombinant NRG-1 activated the HER receptor complex as measured by approximately 4-fold increases in receptor phosphotyrosine content. In addition, NRG-1 increased explant epithelial cell volume density approximately 2-fold (P < 0. 03); increased epithelial cell proliferation approximately 2-fold, as determined by bromodeoxyuridine labeling (P = 0.002); and reduced surfactant protein-A (SP-A) levels by 53% (P < 0.05). These data are consistent with an autocrine regulatory process mediated by NRG-1 activation of HER2/HER3 heterodimers expressed on developing human fetal lung epithelial cells. Receptor activation results in increased lung epithelial cell proliferation and volume density, and decreased SP-A production, a marker of type II pneumocyte differentiation.  相似文献   

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Haemangiopericytoma is a rare soft tissue tumour originating from the contractile pericapillary cells. Relatively little is known about its molecular pathogenesis. To address this issue, the insulin-like growth factor family (IGFs) was analysed in 19 tumours collected from a human tumour bank network. Seven of the tumours were associated with severe hypoglycaemia. Of these, six were retroperitoneal and one was located in the leg. 3 out of the 19 tumours (15·8 per cent) were positive for insulin-like growth factor I (IGF I) mRNA and 11 were positive for IGF II mRNA (57·9 per cent). Almost 90 per cent of haemangiopericytomas expressed IGF I receptor (IGF IR) mRNA (17 out of 19), five (26·3 per cent) expressed IGF binding protein 1 (IGF BP1), three (15·8 per cent) expressed IGF BP2, and four (21 per cent) exhibited IGF BP3 mRNA. All of the 14 haemangiopericytomas examined with regard to specific receptor binding were IGF IR positive, ranging from 1·2 to 16·2 per cent. Binding was much higher in IGF I/IGF IR positive tumours (15·3±0·7) than in IGF I negative/IGF IR positive tumours (5·1±3·3). The potential role of IGF IR as a growth promoting factor in malignant haemangiopericytoma was studied using antisense oligonucleotides and monoclonal antibody αIR3 that specifically inhibit IGF IR synthesis or activity. 10 µM IGF IR antisense oligonucleotides significantly inhibited the growth of haemangiopericytoma cells in culture, by around 50 per cent; monoclonal antibody against IGF IR (αIR3) also significantly inhibited proliferation. The data suggest that IGF IR may play an important role in the genesis and progression of malignant haemangiopericytomas. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

19.
AIMS: To elucidate the mechanism of marked stromal fibrosis in strictured colorectal carcinomas (SC) that cause complete ileus. METHODS AND RESULTS: Sixteen cases of SC and 29 cases of non-strictured colorectal carcinoma (NSC) were studied. These carcinomas showed similar clinicopathological features except for bowel stricture. The stricture index (SI) showing the degree of bowel stricture was 59.8 +/- 12.1% in SC versus 20.8 +/- 24.6% in NSC (P < 0.001). The fibrosis index (FI), defined to reflect the extent of stromal fibrosis, was 56.3 +/- 8.8% in SC versus 21.9 +/- 10.6% in NSC (P < 0.001). COX-2+ myofibroblasts were detected in 13 cases (81.3%) in SC versus eight cases (27.6%) in NSC (P < 0.01). The COX-2+ myofibroblast density was 276.7 +/- 181.1 cells/mm(2) in SC versus 26.6 +/- 52.7 cells/mm(2) in NSC (P < 0.001). When all cases were divided into two groups with and without COX-2+ myofibroblasts, the SI was 48.8 +/- 19.1% in those with COX-2+ myofibroblasts versus 24.8 +/- 29.3% in those with COX-2- myofibroblasts (P < 0.001). CONCLUSION: COX-2+ myofibroblasts may play an important role in extensive bowel stricture in colorectal carcinomas.  相似文献   

20.
R Bose 《Immunology letters》1991,27(2):119-125
Embryo-associated immunosuppressor factor (EASF) is detected by its suppressive properties in the concanavalin A (ConA)-induced lymphocyte proliferation assay. EASF was partially purified from human embryo growth media of in vitro fertilized ova (pre-implantation EASF) as three fractions. The aim of the present study was to determine whether the EASF isolated from human embryo growth media is similar to the EASF secreted by the pre-embryo, which has been shown to be associated with successful pregnancy. EASF activity was measured in the purified pre-implantation EASF fractions and in a total of 24 individual embryo growth media obtained from 10 patients undergoing in vitro fertilization and embryo transfer, where 6 patients achieved successful pregnancy and 4 did not. The results show that: (i) all three EASF fractions and the individual embryo growth media from patients who became pregnant were suppressive when added to the early phase of ConA-supplemented cultures; this was not seen with the embryo growth media from patients who failed to become pregnant, suggesting that the purified pre-implantation EASF may be one of several factors responsible for successful pregnancy; and (ii) some embryo growth media, irrespective of the pregnancy outcome of the patient, showed an irreversible immunosuppressive effect on ConA-induced lymphocyte proliferation, whereas none of the purified EASF fractions did; this could be due to the loss of activity during purification.  相似文献   

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