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991.
Irina V. Tereschenko Victoria M. Basham Bruce A.J. Ponder Paul D.P. Pharoah 《Human mutation》2002,19(2):184-184
We have screened index cases from 25 Russian breast/ovarian cancer families for germ‐line mutations in all coding exons of the BRCA1 and BRCA2 genes, using multiplex heteroduplex analysis. In addition we tested 22 patients with breast cancer diagnosed before age 40 without family history and 6 patients with bilateral breast cancer. The frequency of families with germline mutations in BRCA was 16% (4/25). One BRCA1 mutation, 5382insC, was found in three families. The results of present study, and those of a separate study of 19 breast‐ovarian cancer families, suggest that BRCA1 5382insC is a founder mutation in the Russian population. Three BRCA2 mutations were found in patients with breast cancer without family history: two in young patients and one in patients with bilateral breast cancer. Four novel BRCA2 mutations were identified: three frameshift (695insT, 1528del4, 9318del4) and one nonsense (S1099X). © 2002 Wiley‐Liss, Inc. 相似文献
992.
Myriam Polette Christine Gilles Sophie de Bentzmann Dieter Gruenert Jean-Marie Tournier Philippe Birembaut 《Clinical & experimental metastasis》1998,16(2):105-112
The acquisition of a metastatic phenotype by epithelial cells implicates a series of changes altering their differentiation, their overall behavior and morphology. In the present study, we have examined the relationships between the cellular morphology, E-cadherin expression, matrix metalloproteinases expression and in vitro invasive properties in two human bronchial immortalized cell lines. The (16HBE14o-) cell line which did not show any invasive abilities in the Boyden chamber assay displayed a typical epithelial morphology in monolayer, expressed high levels of E-cadherin and synthesized neither MMP-2 and MT1-MMP nor vimentin. In contrast, the BZR cell line which was highly invasive displayed a more elongated phenotype in monolayer, did not produce E-cadherin but expressed vimentin, MMP-2 and MT1-MMP. Our data therefore suggest that the metastatic progression of broncho-pulmonary cancer cells results in a cellular dedifferentiation and the gain of some mesenchymal attributes (loss of E-cadherin and expression of vimentin) associated with enhanced degradative properties (expression of metalloproteinases).© Rapid Science 1998 相似文献
993.
Kiyosumi Shibata Fumitaka Kikkawa Akihiko Nawa Koji Tamakoshi Nobuhiko Suganuma Yutaka Tomoda 《Clinical & experimental metastasis》1997,15(6):612-619
Ovarian cancer cells disseminate by attachment to the peritoneal mesothelial cell surface of the abdominal cavity. We therefore investigated the influence of conditioned medium (CM) from human peritoneal tissues and mesothelial cells on the secretion of matrix metalloproteinases (MMPs) by ovarian cancer cells. The molecular weights of MMPs stimulating factors derived from human peritoneal tissues and mesothelial cells were estimated using microconcentrators with various cut-off membranes. Human peritoneal tissues were obtained from 12 surgical patients, and mesothelial cells were isolated from three peritoneal specimens. Exposure to CM from peritoneal tissue caused a concentration-dependent increase of the MMP-2 and MMP-9 bands in CM from NOM1 ovarian cancer cells, as shown by zymography. There was a significant difference in the increase of MMP-2 and MMP-9 (2.46-fold and 7.14-fold, respectively, at 0.4mg/ml protein; P < 0.005). CM from mesothelial cells also significantly increased the secretion of MMP-9 by NOM1 cells. The molecular size of possible MMP-9-stimulating factors secreted by peritoneal tissues and mesothelial cells was above M 100000. Further, CM of peritoneal tissues and mesothelial cells also induced the invasiveness of NOM1 cells. These findings suggest that mesothelial cells may secrete some factors which predominantly induce the MMP-9 production and increase invading cell numbers. 相似文献
994.
Werner M Mattis A Aubele M Cummings M Zitzelsberger H Hutzler P Höfler H 《Virchows Archiv : an international journal of pathology》1999,435(5):469-472
The 20q13 region harboring recently described putative oncogenes is frequently amplified in invasive ductal carcinoma (IDC).
The aim of this study was to examine the 20q13 copy number in intraduct hyperplasia (IH), atypical duct hyperplasia (ADH),
and ductal carcinoma in situ (DCIS) adjacent to IDC. In 5 patients, comparative genomic hybridization (CGH) after laser microdissection
revealed 20q13 amplification in four of five cases of IH, in all of three cases of IH with atypia, all five of DCIS, and all
five of IDC. Fluorescence in situ hybridization (FISH) confirmed the amplification at 20q13.2 in IH in the two specimens analyzed.
The amplification rate, however, was higher in DCIS and IDC. In phenotypically normal ductal epithelium normal values were
found for 20q13 copy number by FISH (n=2) and CGH (n=5). Although the number of cases presented here is small, our results suggest that mutations in the 20q13.2 region in IH
may be associated with accelerated proliferation and hyperplasia of the ductal epithelium. Progression to DCIS and ICD is
accompanied by a further increase in the 20q13.2 copy number.
Received: 17 March 1999 / Accepted: 22 June 1999 相似文献
995.
Timo L. M. ten Hagen Ann L. B. Seynhaeve Alexander M. M. Eggermont 《Immunological reviews》2008,222(1):299-315
Summary: Solid tumor therapy with chemotherapeutics greatly depends on the efficiency with which drugs are delivered to tumor cells. The typical characteristics of the tumor physiology promote but also appose accumulation of blood-borne agents. The leaky tumor vasculature allows easy passage of drugs. However, the disorganized vasculature causes heterogeneous blood flow, and together with the often-elevated interstitial fluid pressure, this state results in poor intratumoral drug levels and failure of treatment. Manipulation of the tumor vasculature could overcome these barriers and promote drug delivery. Targeting the vasculature has several advantages. The endothelial lining is readily accessible and the first to be encountered after systemic injection. Second, endothelial cells tend to be more stable than tumor cells and thus less likely to develop resistance to therapy. Third, targeting the tumor vasculature can have dual effects: (i) manipulation of the vasculature can enhance concomitant chemotherapy, and (ii) subsequent destruction of the vasculature can help to kill the tumor. In particular, tumor necrosis factor α is studied. Its action on solid tumors, both directly through tumor cell killing and destruction of the tumor vasculature and indirectly through manipulation of the tumor physiology, is complex. Understanding the mechanism of TNF and agents with comparable action on solid tumors is an important focus to further develop combination immunotherapy strategies. 相似文献
996.
997.
Trends in the incidence of cryptorchidism and hypospadias, and methodological limitations of registry-based data 总被引:7,自引:0,他引:7
Cryptorchidism and hypospadias share possible risk factors, such as intrauterine growth retardation. According to the data collected by the International Clearinghouse for Birth Defects Monitoring Systems (ICBDMS), apparently increasing trends in the incidence of hypospadias were found in Sweden during the 1960s, and in Norway, Denmark, England and Hungary during the 1970s. In Norway and Denmark, the increase continued in the 1980s, while in the USA it has continued from the 1970s to the 1990s. Finland has shown a lower reported rate of hypospadias than other Nordic countries. However, it is difficult to make comparisons between countries because of variable inclusion criteria. Furthermore, the reliability of the data depends on correct ascertainment and reporting of the cases. The ICBDMS has also collected data on cryptorchidism, but these appear to be unreliable because of a discrepancy with the data from cohort studies. According to two comparable English studies, the incidence of cryptorchidism in full-term boys approximately doubled between the 1950s and the 1980s. Regionally there are large differences: e.g. in Finland the incidence of cryptorchidism is clearly lower than in Denmark. Regional and temporal trends may help to identify environmental factors that might be associated with these disorders. 相似文献
998.
Wafaa M. Elzefzafy Soheir Abd Elrahman Nesreen Atef 《Journal of immunoassay & immunochemistry》2020,41(4):729-744
ABSTRACT
Background
Colorectal cancer (CRC) is considered a major cause of morbidity and mortality in Egypt. Colonoscopy is the standard for detection of lesions. The combination of screening methods is effective. Decrease and loss of DPP-IV/CD26 expression and activity are found in microenvironments of specific tumors which are related to impaired immune functions. 相似文献999.
Nae Yu Kim Jung-Soo Pyo Dong-Wook Kang Seung-Min Yoo 《Pathology, research and practice》2019,215(3):580-585
Objective
The aim of this study was to elucidate the clinicopathological significance and prognostic role of loss of claudin-1 in colorectal cancer (CRC).Methods
The correlations between claudin-1 expression and clinicopathological characteristics, including survival rates, were assessed using immunohistochemistry on 260 archival, paraffin-embedded CRC tissues. In addition, the correlations between cludin-1 and nuclear factor-kappa B (NF-κB), epithelial-mesenchymal transition markers and tumor-infiltrating lymphocytes were investigated.Results
Claudin-1 expression was markedly lost in 42.7% of the 260 CRCs analyzed. Loss of claudin-1 expression significantly correlated with larger tumor size, vascular invasion, higher pT stage, and high metastatic lymph node ratio. In addition, loss of claudin-1 expression significantly correlated with NF-κB activation (P?<?0.001), high SNAI (P?<?0.001), and low E-cadherin (P?<?0.001) expressions. Patients with high immunoscores showed significantly lower rates of claudin-1 expression loss (P?=?0.020). In detail, loss of claudin-1 expression were frequently found in CRCs low CD3- and CD8-positive lymphocytes. There were significant correlations between claudin-1 expression loss and poor overall and recurrence-free survivals (P?<?0.001 and P?<?0.001, respectively).Conclusion
Taken together, our results suggest that the loss of claudin-1 expression significantly correlates with aggressive tumor behaviors, high SNAI expression, lower immunoscore, and poor prognoses. 相似文献1000.
Bruinsma F Venn A Lancaster P Speirs A Healy D 《Human reproduction (Oxford, England)》2000,15(3):604-607
Evaluation of the long-term health of children born using in-vitro fertilization (IVF) provides important information to clinicians and consumers. Until very recently, there have been no published data on the incidence of cancer in children conceived as a result of IVF, despite a number of case reports of neuroblastoma in children conceived using fertility drugs. This study used a record-linkage cohort design to investigate the incidence of cancer in children born after IVF. The study included all conceptions using assisted reproductive technologies between 1979 and 1995 at two clinics in Victoria, Australia that resulted in a live birth. Data on births were linked with a population-based cancer registry to determine the number of cases of cancer that occurred. The standardized incidence ratio (SIR) was calculated by comparing the observed number of cases to the expected number of cases. The final cohort included 5249 births. The median length of follow-up was 3 years, 9 months (range 0-15 years). In all, 4.33 cases of cancer were expected and six were observed, giving a SIR of 1.39 (95% CI 0.62-3.09). This study found that children conceived using IVF and related procedures did not have a significantly increased incidence of cancer in comparison to the general population. 相似文献