VEGF, flt-1, and KDR/flk-1 as prognostic indicators in endometrial carcinoma.

Tumor angiogenesis is a highly regulated process under the influence of the host microenvironment and mediators. Studies of breast cancer and, more recently, ovarian and cervical cancer, demonstrate that neovascularization correlates with the likelihood of metastasis and recurrence. Vascular endothelial growth factor (VEGF), an important regulator of tumor angiogenesis in the endometrium, flt-1, and KDR/flk-1 are good markers of vascular proliferation. Being that angiogenesis is a precursor to the development of progressive disease, we hypothesize that quantifying VEGF, flt-1, and KDR/flk-1 expression in uterine malignancies is a superior predictor of metastatic potential and survival than is FIGO grade of tumor, depth of invasion, and histology. The histologic slides of 47 patients with uterine malignancies (35 adenocarcinomas, 6 papillary serous, and 6 carcinosarcomas) were reviewed. The paraffin blocks from the primary tumor were obtained. Immunohistochemistry staining was performed for VEGF, flt-1, and KDR/flk-1. Microvessel density, used to analyze VEGF and receptor concentrations, was determined by two independent investigators, who were blinded to the patients clinical status. The impact of VEGF, flt-1, and KDR/flk-1 as well as stage, grade, depth of invasion, and nodal status on the incidence of metastases, recurrence, and survival was determined using logistic regression analysis and product limit life system survival analysis, respectively. Results indicated that when evaluating all three histologic types, only stage and grade of tumor were found to impact upon the incidence of recurrence and survival. When patients with carcinosarcoma and papillary serous adenocarcinoma were excluded from the analysis, once again only stage and grade of tumor were significant prognostic indicators of recurrence and survival. Only grade of tumor and depth of uterine invasion were significant predictors of a tumor's metastatic potential. VEGF, flt-1, and KDR/flk-1 proved to be of little significance in predicting metastases, recurrence, and survival. Patients with advanced disease in all three histologic subtypes often had low VEGF and receptor positivity. In this study, VEGF, flt-1, and KDR/flk-1 receptor concentrations did not correlate with the incidence of metastases, recurrence, and survival.

Fine BA ，Valente PT ，Feinstein GI ，Dey T ... -  《GYNECOLOGIC ONCOLOGY》

Immunohistochemical localization of vascular endothelial growth factor (VEGF) and its two specific receptors, Flt-1 and KDR, in the porcine placenta and non-pregnant uterus.

Placental angiogenesis and growth are crucial elements in embryonic and later fetal development. Vascular endothelial growth factor (VEGF) and its specific receptors Flt-1 (VEGFR-1) and KDR (VEGFR-2) compose potent ligand receptor systems involved in angiogenesis and microvascular hyperpermeability. In the present immunohistochemical study, VEGF, Flt-1 and KDR were localized in uterus of cyclic non-pregnant pigs and in the porcine epitheliochorial placenta throughout gestation. Emphasis was placed on early gestational stages, where morphological studies have demonstrated extensive angiogenesis during initial placentation. The results revealed a high correlation in spatiotemporal distribution between the ligand and its receptors and a surprising demonstration of VEGF receptors in several non-endothelial cells. In non-pregnant pigs, VEGF, Flt-1 and KDR exhibited moderate to intense staining in uterine luminal epithelium and smooth muscle cells of the vessel walls. Endothelial cells of arteries and arterioles revealed labelling for Flt-1 and KDR, whereas the uterine glandular epithelium displayed intense KDR immunoreactivity at the late luteal phase. During gestation the uterine luminal epithelium demonstrated weak ligand and receptor immunostaining in the first half of early gestation [< or = 21 days post coitus (p.c.)], whereas later stages (> or = 21 days p.c.) displayed intense immunolabelling. Endothelial cells, smooth muscle cells of the vessel walls and uterine glandular epithelium revealed intense ligand and receptor immunoreactivity throughout gestation. In the fetal part of the placenta, VEGF, Flt-1 and KDR immunostaining displayed moderate to intense reactivity in the trophoblast throughout gestation, except during the second half of early gestation (days 21-30 p.c.). Fetal vessel walls were also immunopositive for VEGF, Flt-1 and KDR. Taken together, the results imply that the VEGF, Flt-1 and KDR ligand receptor system participate in the regulations of porcine placentation and that it in addition to its angiogenic properties also may influence the cellular differentiation and transport capabilities in uterine luminal as well as glandular epithelium and the trophoblast.

Winther H ，Ahmed A ，Dantzer V 《PLACENTA》

Expression of vascular permeability factor (vascular endothelial growth factor) and its receptors in endometrial carcinoma.

Solid tumors, including endometrial carcinomas, must induce a vascular stroma to grow beyond a minimal size. The mechanisms responsible for angiogenesis in endometrial carcinoma, however, are not well defined. Vascular permeability factor (VPF), also known as vascular endothelial growth factor (VEGF), is a multifunctional cytokine that is an important regulator of tumor angiogenesis. We evaluated VPF/VEGF mRNA and protein expression, as well as VPF/VEGF receptor mRNA expression, in endometrial carcinoma. Fourteen examples of endometrial carcinoma were evaluated by in situ hybridization; in 7 cases, benign atrophic endometrium from the same patient was also examined. Histologic sections were subjected to in situ hybridization using 35S-labeled riboprobes specific for VPF/VEGF and, in a subset of cases, riboprobes specific for the VPF/VEGF receptors flt-1 and KDR. In addition, ten examples of endometrial carcinoma were evaluated for VPE/VEGF protein expression by immunohistochemistry. All 14 examples of endometrial carcinoma studied by in situ hybridization exhibited focal strong VPF/VEGF mRNA expression by tumor cells. In addition, the endothelial cells of surrounding microvessels strongly expressed flt-1 and KDR mRNAs in all ten cases examined. In contrast, no strong expression of VPF/VEGF, flt-1, or KDR mRNA was observed in the seven examples of benign atrophic endometrium studied. All ten cases of endometrial carcinoma studied by immunohistochemistry exhibited strong VPF/VEGF protein expression by tumor cells. These observations suggest that VPF/VEGF is an important angiogenic factor in endometrial carcinoma.

Guidi AJ ，Abu-Jawdeh G ，Tognazzi K ，Dvorak HF ，Brown LF ... -  《CANCER》

Expression of vascular endothelial growth factor (VEGF) and its receptors (Flt-1 and Flk-1) in esophageal squamous cell carcinoma.

Kato H ，Yoshikawa M ，Miyazaki T ，Nakajima M ，Fukai Y ，Masuda N ，Fukuchi M ，Manda R ，Tsukada K ，Kuwano H ... -  《ANTICANCER RESEARCH》

Vascular stroma formation in carcinoma in situ, invasive carcinoma, and metastatic carcinoma of the breast.

The generation of vascular stroma is essential for solid tumor growth and involves stimulatory and inhibiting factors as well as stromal components that regulate functions such as cellular adhesion, migration, and gene expression. In an effort to obtain a more integrated understanding of vascular stroma formation in breast carcinoma, we examined expression of the angiogenic factor vascular permeability factor (VPF)/vascular endothelial growth factor (VEGF); the VPF/VEGF receptors flt-1 and KDR; thrombospondin-1, which has been reported to inhibit angiogenesis; and the stromal components collagen type I, total fibronectin, ED-A+ fibronectin, versican, and decorin by mRNA in situ hybridization on frozen sections of 113 blocks of breast tissue from 68 patients including 28 sections of breast tissue without malignancy, 18 with in situ carcinomas, 56 with invasive carcinomas, and 8 with metastatic carcinomas. A characteristic expression profile emerged that was remarkably similar in invasive carcinoma, carcinoma in situ, and metastatic carcinoma, with the following characteristics: strong tumor cell expression of VPF/VEGF; strong endothelial cell expression of VPF/VEGF receptors; strong expression of thrombospondin-1 by stromal cells and occasionally by tumor cells; and strong stromal cell expression of collagen type I, total fibronectin, ED-A+ fibronectin, versican, and decorin. The formation of vascular stroma preceded invasion, raising the possibility that tumor cells invade not into normal breast stroma but rather into a richly vascular stroma that they have induced. Similarly, tumor cells at sites of metastasis appear to induce the vascular stroma in which they grow. We conclude that a distinct pattern of mRNA expression characterizes the generation of vascular stroma in breast cancer and that the formation of vascular stroma may play a role not only in growth of the primary tumor but also in invasion and metastasis.

Brown LF ，Guidi AJ ，Schnitt SJ ，Van De Water L ，Iruela-Arispe ML ，Yeo TK ，Tognazzi K ，Dvorak HF ... -  《CLINICAL CANCER RESEARCH》