Delta-like ligand 4 (DLL4) in the plasma and neoplastic tissues from breast cancer patients: correlation with metastasis.

Delta-like ligand 4 (DLL4) is a ligand of the notch pathway. In tumor angiogenesis, DLL4 switches to vascular maturation by providing a negative feedback on VEGFR2 activity. We investigated the expression of DLL4 in the plasma and cancer tissues from breast cancer patients. Plasma samples were collected from 18 women with localized breast cancer, six women with benign breast disease and from six patients with widespread metastatic disease. DLL4 was assessed using ELISA and in cancer tissues using immunohistochemistry. Patients with metastatic breast cancer had significantly higher levels (median 6.7 ± 0.81 ng/ml) compared to patients with localized tumors (median 5.4 ± 0.70 ng/ml) (p = 0.005) and to patients with benign breast disease (median 4.3 ± 0.28) (p = 0.0003). High histology grade was significantly linked with higher plasma DLL4 levels (median 5.59 ± 0.62 vs. 5.12 ± 0.44 ng/ml; p = 0.01). Surgical removal of high-grade breast cancer resulted in significant reduction in DLL4 plasma levels (p = 0.003). DLL4 was expressed in tumor-associated vessels and in cancer cells. The ratio of DLL4+/CD31+ vascular density (VD) ranged from 23 to 88% (median 49 %). High DLL4 cancer cell expression and high DLL4+ VD were significantly linked with nodal involvement (p = 0.004 and 0.01, respectively). Linear regression analysis showed a significant association of DLL4 plasma levels with the percentage of DLL4+ cancer cells (p = 0.03, r = 0.50) and with DLL4+ VD (p = 0.0007, r = 0.60). It is concluded that DLL4 is overexpressed in breast cancer cells and breast cancer vasculature and is linked with nodal and distant metastasis. DLL4 plasma levels measurement can reliably estimate the total DLL4 breast cancer/vasculature activity.

Serum VEGF levels and tissue activation of VEGFR2/KDR receptors in patients with breast and gynecologic cancer.

OBJECTIVES: Vascular endothelial cell growth factor (VEGF) plays an important role in the biology of gynecological cancer, usually linked with aggressive tumour behaviour and a poor postoperative outcome. Yet, its role in benign breast/gynecological conditions is less clear. METHODS: Serum VEGF was analysed in a series of 49 patients with gynecological cancer and 61 patients with benign disease and compared to those of 12 normal female subjects. In addition, the activation status of VEGFR2/KDR receptors was investigated in formalin-fixed paraffin embedded tissues and related to VEGF. RESULTS: Mean serum levels of VEGF were significantly higher in patients with breast, endometrial and ovarian cancer compared to healthy controls and those with benign breast/gynecologic disease in the respective organs. A similar trend was noted in some cases of simple endometrial hyperplasia, fibroadenoma and fibrocystic disease of the breast. The expression of phosphorylated VEGFR2/KDR receptors was higher in breast, endometrial, ovarian cancer in patients with high VEGF serum levels and this reached a level of statistical significance when all malignancies were combined. CONCLUSIONS: Serum VEGF levels are increased in patients with breast and gynecological malignancies, but this can not be considered pathognomonic for cancer as it is also increased in certain benign conditions, including cases of fibroadenoma, fibrocystic disease of breast and simple endometrial hyperplasia. Furthermore, high serum VEGF levels are closely related to the activation status of the VEGFR2/KDR receptor in cancer cells, indicating a stimulatory effect of serum VEGF on the VEGF pathway contributing to tumor progression.

Smoking and AMH levels in women with normal reproductive history.

PURPOSE: To investigate the effect of age and smoking on the AMH levels in normal cycling healthy women with normal reproductive history. MATERIALS AND METHODS: In 137 women, blood samples were taken on day 3 of a spontaneous cycle. Serum FSH, LH, E2, progesterone and AMH were measured in all blood samples. For the statistical analysis of the data, t test, Pearson's correlation and linear regression analysis were performed. RESULTS: Of 137 women (43%), 59 were smokers. Age was positively correlated with serum FSH and LH levels (r = 0.584, P < 0.001 and r = 0.330, P < 0.001, respectively) and negatively correlated with serum AMH levels (r = -0.882, P < 0.001). There were no significant differences in FSH, LH, E2, progesterone and AMH levels between smokers and non-smokers. Multiple stepwise linear regression analysis showed that in both smokers and non-smokers, age was the most significant determinant of AMH levels (r = -0.889, P < 0.001 and r = -0.944, P < 0.001, respectively), while smoking was not related to AMH levels. CONCLUSIONS: Aging significantly decreases AMH levels in women with normal cycles and normal reproductive history, while smoking does not seem to have significant effects on AMH levels.