The Mediterranean fruit fly, Ceratitis capitata, is a pest of major economic importance and has become a model for the development of SIT control programs for insect pests. Significant information has been accumulated on classical and population genetics of this species during the past 2 decades. However, the availability of molecular markers is limited. Here, we present the isolation and characterization of 159 microsatellite clones and the development of 108 polymorphic microsatellite markers for this insect pest. Mapping by in situ hybridization to polytene chromosomes of 21 microsatellite clones enriched the cytogenetic map that was previously constructed by our group. The enriched map provides a large number of STSs for future genome mapping projects. Cross-species amplification of these microsatellite loci in 12 Tephritidae species and sequence analysis of several amplification products indicated a varying degree of transferability and their possible usefulness as molecular and genetic markers in these species where genetic and molecular tools are limited.
Malignant gliomas are angiogenesis dependent and present a remarkable degree of resistance to radiotherapy. In the present work, we studied the effect of irradiation of C6 glioma cells on their proliferation and activation in vitro and on glioma cell-induced angiogenesis in vivo and in vitro. Irradiation of C6 glioma cells decreased cell proliferation in a dosedependent manner. Interestingly, metalloproteinase-2 and -9 expression and secretion, as well as integrin ␣ v expression, increased with elevated doses of X rays 48 hr after irradiation and was mostly evident at the higher doses used. When pre-irradiated C6 cells were implanted on nonirradiated chicken embryo chorioallantoic membranes (CAMs), there was a significant dose-dependent increase in tumor induced angiogenesis, compared to angiogenesis induced by nonirradiated cells. Similar results were obtained when C6 cells were irradiated 48 hr after their inocculation onto nonirradiated CAMs. In the same line, conditioned medium from irradiated C6 cells significantly increased endothelial cell proliferation and migration in vitro, in a manner dependent on the dose of X rays. These results explain at least in part the low effectiveness of radiation therapy of malignant gliomas and support the notion that inhibition of angiogenesis in parallel with radiotherapy may represent a new therapeutic approach. © 2004 Wiley-Liss, Inc. Key words: angiogenesis; endothelial cells; glioma cells; metalloproteinase-2; migration; proliferation; X raysMalignant gliomas, the most common type of brain tumors in adults, present a remarkable degree of neovascularisation and invasiveness into surrounding tissues. 1 These features account for their poor prognosis, and although combinations of surgery, radiotherapy and chemotherapy are used, more than 90% of the patients experience local recurrence and their survival is extremely low. These facts stress the need for more effective therapeutic strategies. 2 Rapid cell proliferation and high invasive capacity of glioma cells are crucial for tumor development and progression. Moreover, induction of angiogenesis is an essential prerequisite for tumor growth and spread, and precedes malignant tumor formation. 3 Angiogenesis is a fundamental process by which new blood vessels are formed from pre-existing ones. It is a very important step in reproduction, development and wound healing. Furthermore, angiogenesis is very important in several pathological mechanisms like carcinogenesis, tumor metastasis and inflammation. 4 Radiation is considered to inhibit angiogenesis through damage to the endothelium. 5,6 However, in vivo studies suggest that ionizing radiation induces vascular endothelial growth factor (VEGF) production 7 and enhances both the formation of new blood vessels 8 -11 and the secondary development of tumors. 11-13 We have previously shown in the in vivo system of the chicken embryo chorioallantoic membrane (CAM) that X-rays enhance angiogenesis induced by C6 glioma cells inoculated onto the tissue immediately after irradiation...
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