Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 4

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  tumour metastasis
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Introduction. The biological activity of VEGF depends on the presence of its specific receptors on the endothelial surface: VEGFR-1, VEGFR-2, and on their soluble forms sVEGFR-1 and sVEGFR-2. The binding of the membrane-bound receptors with VEGF affects the permeability, proliferation and migration of vascular endothelial cells. This creates the necessary conditions for the vascularisation of solid tumours and for the spread of remote metastases. The sVEGFR-1 and sVEGFR-2 receptors are believed to be natural inhibitors of VEGF. Objective. To determine the clinical usefulness of VEGF and the sVEGFR-1 and sVEGFR-2 receptors level assay in women with primary breast cancer. The assessment also took into account: patient’s age, stage of the disease, histological grade, status of the axillary lymph nodes and size of the primary tumour. Material and methods. The concentrations of VEGF, sVEGFR-1 and sVEGFR-2 were ascertained in 103 women with primary breast cancer. The concentrations of VEGF in the plasma, and those of the soluble receptors sVEGFR-1 and sVEGFR-2 in the serum, were assessed by ELISA, R&D Systems. Results. The study found significantly raised concentrations of VEGF, sVEGFR-1 and sVEGFR-2 in the serum of women with breast cancer, relative to the values obtained from the control group. It was found that with increasing clinical stages of the disease, the levels of VEGF and concentrations of sVEGFR-1 and sVEGFR-2 also increased. Similar findings were noted when assessing the degree of the histological grade of the tumours. Significantly higher values of VEGF protein and the assessed receptors were obtained from women with metastases to the axillary lymph nodes. A positive relationship, though without statistical significance, was noted between the concentration of sVEGFR-2 and the size of the tumour. Conclusions. The high concentrations of the VEGF cytokine and the sVEGFR-1 and sVEGFR-2 receptors in women with breast cancer are responsible for giving rise to the processes of tumour angiogenesis. The concentrations of the VEGF protein and the soluble forms of the receptors sVEGFR-1 and sVEGFR-2 in the serum of breast cancer patients showed positive correlations with the clinical stage of the disease. These results point to the usefulness of VEGF assessment and its soluble receptors in the clinical evaluation of patients with breast cancer.
Tissue-specific heterogeneity of endothelial cells, both structural and functional, plays a crucial role in physiologic as well as pathologic processes, including inflammation, autoimmune diseases and tumor metastasis. This heterogeneity primarily results from the differential expression of adhesion molecules that are involved in the interactions between endothelium and circulating immune cells or disseminating tumor cells. Among these molecules present on endothelial cells is hyaluronan (HA), a glycosaminoglycan that contributes to primary (rolling) interactions through binding to its main receptor CD44 expressed on leukocytes and tumor cells. While the regulation of CD44 expression and function on either leukocytes or tumor cells has been well characterized, much less is known about the ability of endothelial cells to express HA on their surface. Therefore, in these studies we analyzed HA levels on tissue-specific endothelium. We used endothelial cell lines of different origin, including lung, skin, gut and lymph nodes that had been established previously as model lines to study interactions between the endothelium and leukocytes/tumor cells. Our results indicate that HA is accumulated on the surface of all endothelial cells examined. Moreover, retention of endogenous HA differs between the lines and may depend on their tissue origin. Analysis of binding of exogenous HA reveals the presence of specific HA binding sites on all endothelial cell lines tested. However, the retention of endogenous HA and the binding of exogenous HA is mediated through a CD44-independent mechanism.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.