Proliferation and maturation of intratumoral blood vessels in women with malignant ovarian tumors assessed with cancer stem cells marker nestin and platelet derived growth factor PDGF-B.

OBJECTIVES

Platelet-derived growth factor B (PDGF-B) and nestin have been suggested to be useful in the assessment of neoangiogenesis in malignant ovarian masses. We aimed to investigate a possible association of these markers with newly formed microcapillaries and perivascular cells in ovarian tumors.

MATERIAL AND METHODS

Microvessel density (MVD) and pericytes were studied in 82 women with ovarian neoplasms, including 7 benign cysts, 7 borderline masses, 64 epithelial ovarian cancers and 4 other malignant ovarian tumors. Immunohistochemical staining included antibodies to CD34, PDGF-B and nestin.

RESULTS

Median values of CD34-positive and nestin-positive MVD were: 24,5 (range:17-32) and 21 (range: 12-31), respectively. No significant correlation between intratumoral CD-34 positive MVD and nestin-positive MVD was found. Benign and borderline lesions more frequently than malignant tumors displayed low or medium values of nestin-positive MVD (p = 0.01). Histological grading of malignant tumors was associated with nestin-positive MVD (p = 0.01). Nestin expression in tumor cells was not correlated with tumor grade or histological subtype. PDGF-B expression was found in tumor microves-sels in 72% of cases (59/82). High expression of PDGF in pericapillary cells was strongly associated with high expression of this marker in cancer cells (p = 0.007). Significant correlations between PDGF-B and nestin expression in malignant tumor microvessels were also found (p = 0.04). Nestin and PDGF-B expressions were strongly associated with high grade tumors when compared to low grade or benign masses.

CONCLUSIONS

We conclude that the assessment of PDGF-B and nestin-positive MVD could be used to identify only highly active, angiogenic malignant ovarian masses, where tumor vasculature is formed.