Microvessel Density Values Research Articles

Microvessel density and vascular endothelial growth factor expression in sinus augmentation using Bio‐Oss®

The aim of this study was to evaluate microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression in sinus augmentation with Bio-Oss. Twenty patients participated in this study. The sinuses were filled with 100% Bio-Oss. Implants were inserted after 3 months in group A, and 6 months in group B. A trephine was used to harvest bone cores. As control, the pre-existing subantral bone was used. The mean MVD in control bone was 23.6 +/- 1.8. In the sites augmented with Bio-Oss, at 3 months, the MVD was 23.3 +/- 2.1, while in the sites retrieved at 6 months the MVD was 29.5 +/- 2.4. The difference in MVD between the control bone and group A was not statistically significant. The difference between the control bone and group B was statistically significant (P < 0.05). The statistical analysis showed that the difference in MVD between group A and group B was statistically significant (P < 0.05). Bio-Oss seemed to induce an increase in MVD that reached a higher value after 6 months. The percentage of vessels positive to VEGF was higher in group A than in group B. Our data also showed a higher percentage of vessel and stromal cells positive to VEGF and higher MVD values in areas where there was newly formed bone compared with areas where maturation processes were occuring, and this fact could point to a close spatial relationship between angiogenesis and osteogenesis.

Angiogenesis in pterygium: study of microvessel density, vascular endothelial growth factor, and thrombospondin-1

This retrospective study aims to elucidate the role of angiogenesis in the pathogenesis of pterygium. We evaluated microvessel density (MVD), and expression of vascular endothelial growth factor (VEGF) and thrombospondin-1 (TSP-1). Fifty-two surgically excised pterygia and seven normal conjunctivae were immunohistochemically studied applying the streptavidin-biotin method in paraffin-embedded tissue sections. Monoclonal antibodies were targeted against CD31, VEGF, and TSP-1 proteins. Pterygium presented with statistically significant higher average count of microvessels compared to normal conjunctivae (17.97+/-8.5 vs5.72+/-5 per high power field, P=0.001). In 24/52 (46.2%) cases of pterygium, high expression levels for VEGF were demonstrated, whereas the mean percentage of VEGF-positive epithelial cells was 58.03%. Furthermore, normal conjunctival presented statistically significant higher expression levels for VEGF in epithelial cells (83.14+/-36.08 vs58.03+/-31.23%, P=0.007). On the contrary, the presence of VEGF immunoreactivity in vascular endothelial and stromal cells was significantly higher in pterygium tissues (P<0.0001). Stromal staining for TSP-1 was detected in only 29/52 (55.8%) of the cases and no correlation with normal conjunctivae was found. Finally, statistically significant positive correlation between MVD values and stromal VEGF expression was found (P=0.049). The angiogenesis-related factors that were studied proved to be highly expressed in pterygium tissue. On the contrary, TSP expression level was low, allowing inducers of angiogenesis to act uninhibited. This phenomenon could provide the pathogenic basis of pterygium formation.

Antiangiogene strahlentherapeutische Effekte als von der anfänglichen Kapillardichte unabhängige prädiktive Faktoren des Überlebens bei inoperablem oropharyngealen Plattenepithelkarzinom

To evaluate the predictive value of intratumoral microvessel density (MVD) in patients with locally advanced, primarily inoperable oropharyngeal cancer (OPCC) treated with irradiation alone. Tumor samples of 35 patients with OPCC subjected to radiotherapy were taken before and after 20 Gy irradiation. Histological grade, mitotic activity index and MVD of OPCC were determined. Correlations with response and survival were analyzed. Stage and posttreatment MVD decrease showed significant correlation with objective response. Postirradiation MVD decrease correlated significantly with response to irradiation and overall survival, and a trend could be seen for progression-free survival. This study has shown that the change in MVD after irradiation can be an indicator of the success of radiotherapy in locally advanced OPCC, and may serve as a predictive factor thus helping to select patients who could benefit from more aggressive treatment.

Prognostic significance of microvessel density and vascular endothelial growth factor expression in sinonasal carcinomas

The prognostic significance of microvessel density and proliferative activity of the neoplastic cells, evaluated respectively by CD31 and Ki-67 positivity, and immunohistochemical expression of vascular endothelial growth factor (VEGF) was retrospectively investigated in 105 cases of sinonasal carcinoma (80 surgical specimens and 25 biopsies). The most represented histologic types were intestinal-type adenocarcinoma found in 36 patients (34.3%), squamous cell carcinoma (SCC) in 34 (32.4%), mucinous adenocarcinoma (mainly made up of signet-ring cell patterns) in 15 (14.3%), and adenoid cystic carcinoma in 7 (6.7%). Microvessel density values (in vessels per square millimeter), VEGF, and Ki-67 were not dependent on histologic type but were rather correlated to the histologic grading in SCC. Clinical data were available for 92 (87.6%) of 105 patients, with minimum follow-up of 48 months. Most of the patients (81.5%) were at an advanced stage (T3-T4) at diagnosis. The values of all markers were correlated to tumor stage (P = .03). Multivariate analysis showed that both microvessel density and proliferative activity of the neoplastic cells were independent prognostic parameters (mortality hazard ratio, 1.33 and 1.60, respectively). Although VEGF expression was not correlated to prognosis on the whole series (P = .06), it was a powerful prognostic marker when the analysis was restricted to the group of SCCs (hazard ratio, 3.02; 90% confidence interval, 1.58-5.80). These results show that tumor neoangiogenesis, expressed by microvessel density, together with proliferative activity, is a pathologic marker with a strong prognostic impact in sinonasal carcinomas. Therefore, it may be a useful tool in this field so as to carry out therapeutic protocol planning, which may be further enhanced by the adoption of the more recent antiangiogenic molecules.

Correlative studies on uPA mRNA and uPAR mRNA expression with vascular endothelial growth factor, microvessel density, progression and survival time of patients with gastric cancer

To investigate the correlations between the expression of urokinase-type plasminogen activator (uPA) mRNA, uPA receptor (uPAR) mRNA and vascular endothelial growth factor (VEGF) protein and clinicopathologic features, microvessel density (MVD) and survival time. In situ hybridization and immuno-histochemistry techniques were used to study the expressions of uPA mRNA, uPAR mRNA, VEGF and CD34 protein in 105 gastric carcinoma specimens. Expressions of uPA mRNA, uPAR mRNA and VEGF protein were observed in 61 (58.1%) cases, 70 (66.7%) cases and 67 (63.8%) cases, respectively. The uPA mRNA and uPAR mRNA positive expression rates in infiltrating-type cases (73.7%, 75.4%), stage III-IV (72.1%, 75.4%), vessel invasion (63.2%, 69.9%), lymphatic metastasis (67.1%, 74.4%) and distant metastasis (88.1%, 85.7%) were significantly higher than those of the expanding-type (chi2 = 15.57, P = 0.001; chi2 = 6.91, P = 0.046), stage I-II (chi2 = 19.22, P = 0.001; chi2 = 16.75, P = 0.001), non-vessel invasion (chi2 = 11.92, P = 0.006; chi2 = 14.15, P = 0.002), non-lymphatic metastasis (chi2 = 28.41, P = 0.001; chi2 = 22.5, P = 0.005) and non-distant metastasis (chi2 = 12.32, P = 0.004; chi2 = 17.42, P = 0.002; chi2 = 11.25, P = 0.012; chi2 = 18.12, P = 0.002). The VEGF positive expression rates in infiltrating-type cases (75.4%), stage III-IV (88.5%), vessel invasion (82.9%), lymphatic metastasis (84.3%) and distant metastasis (95.2%) were significantly higher than those of the expanding-type (chi2 = 9.61, P = 0.021), stage I-II (chi2 = 16.66, P = 0.001), non-vessel invasion (chi2 = 29.38, P = 0.001), non-lymphatic metastasis (chi2 = 18.68, P = 0.005), and non-distant metastasis (chi2 = 22.72, P = 0.007; chi2 = 21.62, P = 0.004). The mean MVD in the specimens positive for the uPA mRNA, uPAR mRNA and VEGF protein was markedly higher than those with negative expression groups. Moreover, a positive relation between MVD and uPA mRNA (rs = 0.199, P = 0.042), uPAR mRNA (rs = 0.278, P = 0.035), and VEGF (rs = 0.398, P = 0.048) expressions was observed. The mean survival time in cases with positive uPA mRNA, uPAR mRNA and VEGF protein expression or MVD value > or = 54.9 was significantly shorter than those in cases with negative expression or MVD value < 54.9. uPA and uPAR expressions are correlated with enhanced VEGF-induced tumor angiogenesis and may play a role in invasion and nodal metastasis of gastric carcinoma, thereby serving as prognostic markers of gastric cancer.

Microvessel density is a prognostic marker of human gastric cancer

To investigate whether microvessel density (MVD) is related with prognosis in gastric cancer patients, and the expression of cyclooxygenase-2 (COX-2) and vessel endothelial growth factor (VEGF) so as to determine the possible role of COX-2 and VEGF in gastric cancer angiogenesis. Forty-seven formalin-fixed paraffin-embedded tissue samples of gastric cancer were evaluated for COX-2, VEGF by immunohitochemical staining. To assess tumor angiogenesis, MVD was determined by immunohitochemical staining of endothelial protein factor VIII-related antigen. The relationship among COX-2 and VEGF expression, MVD, and clinicopathologic parameters was analyzed. Among the 67 samples, high MVD was significantly associated with lymph node metastasis and poor survival. Multivariate survival analysis showed that MVD value and lymph node metastasis were independent prognostic factors. The expression rate of COX-2 and VEGF was significantly higher than that of the adjacent tissues. COX-2 and VEGF expression in gastric cancer was significantly correlated with tumor differentiation and depth of invasion, but not with survival. The mean MVD value of COX-2 or VEGF positive tumors was higher than that of COX-2 or VEGF negative tumors. A significant correlation was found between the expressions of COX-2 and VEGF. MVD may be one of the important prognostic factors for gastric cancer patients. COX-2 and VEGF may play an important role in tumor progression by stimulating angiogenesis. VEGF might play a main role in the COX-2 angiogenic pathway. The inhibition of angiogenesis or COX-2, VEGF activity may have an important therapeutic benefit in the control of gastric cancer.

Inflammatory Infiltrate, Microvessel Density, Nitric Oxide Synthase Expression, Vascular Endothelial Growth Factor Expression, and Proliferative Activity in Peri‐Implant Soft Tissues Around Titanium and Zirconium Oxide Healing Caps

The aim of the present study in humans was to conduct a comparative immunohistochemical evaluation of vascular endothelial growth factor (VEGF) and nitric oxide synthase (NOS) expression, inflammatory infiltrate, proliferative activity expression, and microvessel density (MVD) in peri-implant soft tissues of titanium and zirconium oxide healing caps. Five patients, three men and two women (aged 30 to 66 years; mean: 49 years), participated in this study. All patients received dental implants that were 3.8 mm in diameter and 11 mm in length. All implants were left to heal in a non-submerged (single-stage) mode. Healing caps (3.8 mm in diameter and 3.0 mm in height) were inserted in all implants. Half of the implants were supplied with standard, prefabricated caps of commercially pure titanium, whereas the other half were provided with test zirconium oxide caps. After a 6-month healing period, a gingival biopsy was performed with a circular scalpel (5.5 mm in diameter) around the healing caps of both groups, without unscrewing or removing the healing caps. The dimensions of the gingival biopsies were 1.7 mm (5.5-3.8 mm) in thickness and 3 mm in height. Statistically significant differences were found in the microvessel density between titanium and zirconium oxide healing caps and group II (P < or = 0.0001). Statistically significant differences were likewise found in the low and high intensities of NOS1, NOS3, and VEGF (P < or = 0.0001). In conclusion, the high intensity of NOS1, NOS3, and VEGF were mostly expressed in the titanium group, whereas the low intensity of NOS1, NOS3, and VEGF were mostly expressed in the zirconium oxide group. In our specimens, the inflammatory infiltrate was mostly present in the titanium specimens. Their extension was much larger than that of the zirconium oxide specimens. Higher values of MVD were observed in the titanium specimens (29.1 versus 15.8). In addition, a higher expression of VEGF intensity was observed in the peri-implant tissues of titanium healing caps, whereas predominantly lower expressions of VEGF intensity were noted around the zirconium oxide healing caps. The Ki-67 expression was higher in the titanium specimens. All these data revealed that the tissues around titanium healing caps underwent a higher rate of inflammation-associated processes, most probably correlated to the higher inflammation processes observed in these tissues. A higher intensity expression of NOS1 and NOS3 was recorded in the tissues around titanium, whereas, on the contrary, a lower intensity of expression was found in the tissues around zirconium oxide specimens. These latter data indicate that the higher expression of these two mediators could be correlated to the higher amount of bacteria present around the titanium samples.

Angiogenesis in malignant lymphoma

Angiogenesis plays an important role in the pathophysiology of both solid tumors and hematologic malignancies. Angiogenesis-associated parameters are important prognosticators, and tumor blood vessels are an emerging target for therapy. This review addresses the evidence of the role of angiogenesis in malignant lymphoma and discusses some therapeutic implications. In angiogenesis assays, lymphoma cells show angiogenic properties. Tumor vascularization is higher in lymphoma tissue than in reactive lymph nodes and increases in step with clinically more aggressive lymphoma subtypes and advanced-stage disease. High levels of vascular endothelial growth factor in blood and tissue are associated with adverse prognosis. Vascular endothelial growth factor and vascular endothelial growth factor receptors are also present in lymphoma cells. Therapy against vascular endothelial growth factor in animal models is effective and points to both the tumor cell and the host endothelium as targets. Structural microvessel abnormalities are present in some lymphoma subtypes. The role of angiogenesis might vary in lymphoma subtypes because the prognostic value of microvessel density and the expression of angiogenesis-related molecules differ between lymphoma subtypes. There are also differences in blood vessel phenotype between lymphoma subtypes. This heterogeneity may have implications for antiangiogenic therapies. Antiangiogenic therapy in human lymphoma is still in its infancy. The role of angiogenesis in malignant lymphoma is evident. Tumor vasculature is an attractive target for lymphoma therapy. Differences between lymphoma subtypes must be taken into account in the selection of the most suitable patients for trials with antiangiogenic agents.

Accelerated lymphangiogenesis in malignant lymphoma: possible role of VEGF‐A and VEGF‐C

There is little information regarding the lymphangiogenesis of malignant lymphoma. In this study, we evaluated the lymphangiogenesis and angiogenesis in 44 lymph nodes of 39 malignant lymphomas and five non-reactive normal lymph nodes, based on the lymphatic vessel density (LVD) and microvessel density (MVD) calculated by the computer-assisted assessment of vessel density. The LVD of malignant lymphomas was significantly higher than that of non-reactive normal lymph nodes, irrespective of subtypes (P = 0.00077). On the contrary, there was no difference in MVD between malignant lymphomas and non-reactive normal lymph nodes, except for diffuse large B cell lymphomas, which had a significantly low value of MVD, in comparison with non-reactive normal lymph nodes (P = 0.009). We further examined the expression of vascular endothelial growth factor (VEGF)-C and VEGF-A, which function on lymphangiogenesis in lymph node samples. VEGF-C was expressed in 36 of 39 malignant lymphomas. All 39 of the malignant lymphoma samples expressed VEGF-A. Furthermore, the level of LVD and VEGF-A or VEGF-C was positively correlated. These findings suggest that lymphangiogenesis is actively developed in lymph nodes of malignant lymphomas and it may be induced by both VEGF-A and VEGF-C secreted from lymphoma cells.

Evaluation of tumour microvessel density & pericyte coverage index following neoadjuvant chemotherapy in primary breast cancer

655 Background: Angiogenesis is critical for the growth & metastasis of breast tumours & can be quantified using intratumoural microvessel density (MVD). Pericyte recruitment to the tumour microvasculature is thought to reflect vessel maturation & thus pericyte coverage index (PCI) provides a qualitative measure of tumour angiogenesis. Here we assess the effect of anthracycline-based neoadjuvant chemotherapy (NAC) on MVD & PCI in primary breast cancer (PBC). Methods: Paired pre- & post-treatment pathological specimens (diagnostic core biopsy & definitive surgical resection specimen respectively) from 80 women with PBC (median age 47 years; range 29 - 70) who received 5-fluorouracil, epirubicin & cyclophosphamide (FEC) NAC were analysed. Immunohistochemical double-staining was performed using the panendothelial marker, CD34, & alpha-smooth muscle actin (α -SMA). MVD & PCI were scored from random fields (median 9; range 2–31) at x200 magnification or, in the case of small samples (n=20), from all fields (median 2; range 1–12). Individual microvessels (CD34 positive) were counted per field & expressed per mm2. PCI was scored as the number of CD34 & α -SMA positive vessels & expressed as a percentage of all CD34 positive vessels within the field. Change in median MVD & PCI following NAC was evaluated using the Wilcoxon’s signed rank test. Results: The median (interquartile range) pre-NAC MVD & PCI values were 76.4/mm2 (46.5 - 106.6/mm2) & 17.3% (6.6 - 30.4%) respectively & post-NAC MVD & PCI values were 72.2/mm2 (50 - 100/mm2) & 25.5% (18.2 - 43.3%) respectively. There was no significant difference between the pre- & post-NAC MVD values (p = 0.48), however, there was a significant difference between the pre- & post-NAC PCI values (p<0.0001) with an increase in PCI following NAC. Conclusions: The MVD of breast tumours following FEC NAC is not significantly different to that measured in the pre-NAC diagnostic core biopsy samples. A significant increase in the PCI of the tumour microvasculature occurs following NAC. This would suggest a differential effect of NAC on the tumour microvasculature according to functional vascular status, with a reduction in the proportion of “immature” blood vessels. No significant financial relationships to disclose.

Echo Contrast-Enhanced Power Doppler Ultrasonography for Assessment of Angiogenesis in Renal Cell Carcinoma

Tumoral growth is an angiogenesis-dependent event. Although there are studies about the importance of histopathologic angiogenesis in various malignancies, the assessment of the angiogenesis by radiologic techniques is not well established. The aim of this study was to investigate the efficacy of echo contrast-enhanced power Doppler ultrasonography (PDUS) in determining the angiogenic status of renal cell carcinoma (RCC). Power Doppler ultrasonography was performed before and after intravenous administration of an echo contrast agent in 42 patients with renal masses. Twenty-one of these renal masses were diagnosed as RCC histopathologically, and these 21 patients were reevaluated retrospectively. The color pixel ratios of selected images were calculated as the ratio of the number of pixels showing power Doppler signals to the total number of pixels within the lesion. The results were compared with the histopathologic microvessel density (MVD). A significant correlation was found between color pixel ratio and MVD values in both PDUS techniques. The use of the echo contrast agent improved this correlation and P values (Spearman rho from 0.436 to 0.551; P from .048 to .01). Color pixel ratio values reflect the MVD in RCC. Therefore, these results suggest that preoperative quantification of angiogenesis can be possible with the help of PDUS in RCC.

Evaluation of tumor angiogenesis measured with microvessel density (MVD) as a prognostic indicator in nasopharyngeal carcinoma: Results of RTOG 9505

The objective of this study was to evaluate tumor angiogenesis as measured by microvessel density (MVD) as an independent prognostic factor in patients with nasopharyngeal carcinoma (NPC) treated with radiotherapy alone. Eligible patients included those with NPC treated with radiotherapy. Paraffin blocks of the primary tumor had a hematoxylin and eosin-stained section prepared at the block face. One representative section for tumor was stained for factor VIII-related antigen using a standard immunoperoxidase staining technique. MVD was determined by light microscopy in areas of invasive tumor containing the highest numbers of capillaries and microvessels per area. Individual microvessel counts were made on a 200x field within the area of most intense tumor neovascularization. Results were expressed as the highest number of microvessels identified within any single 200x field. Using a breakpoint of MVD <60 vs. > or =60, the distributions between the two MVD groups were compared by the method of Gray. Overall survival rates were estimated by the Kaplan-Meier method and compared by the log-rank test. A multivariate Cox proportional hazard model was employed to examine the relationship between MVD and disease outcomes while adjusting for other concomitant variables. One hundred sixty-six were eligible, of whom 123 had values determined for MVD. The MVD values ranged from 9 to 243 with a median of 70. In the multivariate analysis of overall survival, distant metastases, and local-regional failure, MVD did not significantly improve the model containing T stage, N stage, age, radiation dose, and World Health Organization class. We found no significant differences in overall survival, time to distant metastasis, or time to local-regional failure using a breakpoint of MVD <60 vs. MVD > or =60. The study was perhaps limited by the small size of the NPC samples.

Prognostic relevance of CD105+ microvessel density in HNSCC patient outcome

Angiogenesis is essential for the development and progression of malignant tumours, and there is increasing evidence that microvessel density (MVD) can be considered an indirect marker of neo-angiogenesis. However, there is still disagreement concerning the clinical relevance and prognostic significance of MVD in head and neck squamous cell carcinomas (HNSCCs). MVD was evaluated in 127 HNSCC patients by means of immunohistochemistry using monoclonal antibodies (mAbs) against CD34 and CD105 (endoglin), which has recently been described as a potent marker of neo-vascularisation in various malignancies. MVD was expressed as the mean number of vessels/mm2. The mean CD34+ and CD105+ MVD values were significantly higher in T3-T4 tumours and those in an advanced clinical stage; furthermore, CD105+ MVD was significantly higher in N+ tumours. The patients with a high CD105+ MVD had a significantly shorter disease-free and overall survival; CD34+ MVD was not associated with survival. Similarly, in the subset of lymph-node negative patients, higher CD105+ MVD values were significantly associated with either OS and DFS. Multivariate analysis showed that a high CD105+ MVD was the only independent marker of tumour recurrence or death. Our data suggest that CD105+ MVD may represent an additional prognostic factor in HNSCC patients providing more accurate data for the determination of prognosis and management in the subset of lymph node negative patients.

Bladder transitional cell carcinoma: correlation of contrast enhancement on computed tomography with histological grade and tumour angiogenesis

AIM: To investigate the correlation between the degree of contrast enhancement of bladder cancer in the early enhanced phase of helical computed tomography (CT) and microvessel density (MVD), vascular endothelial growth factor (VEGF) and histological grade. MATERIALS AND METHODS: Sixty-five patients with transitional cell carcinoma of the bladder were examined by incremental unenhanced CT and helical CT at 40–45 s after initiation of intravenous administration of contrast medium before surgery. The CT density in Hounsfield units of bladder carcinomas were measured in the middle of the maximum diameter section of the cancer lesions on unenhanced and enhanced CT. The degree of contrast enhancement of the tumour was determined as the absolute increase in Hounsfield units. Histological grade, VEGF and MVD were analysed for each cancer. The Pearson and Spearman correlation tests were used to determine the strength of the relationships between CT enhancement and histological grade, VEGF expression and MVD. RESULTS: Different degrees of enhancement were observed in 91 cancers during the early enhanced phase of helical CT. Mean MVDs and mean CT enhancing values of different histological grade groups were statistically different ( p<0.001). A positive correlation was found in the CT-enhancing value of bladder cancer and MVD (Pearson correlation test; r=0.938, p<0.001) and histological grade (Spearman rank correlation; r=0.734, p<0.001). VEGF of bladder cancer did not correlate with the change in CT attenuation (Spearman rank correlation; r=0.087, p=0.410) and MVD (Spearman rank correlation, r=0.103, p=0.330). CONCLUSION: In bladder cancer, the degree of contrast enhancement during the early enhanced helical CT is correlated with the MVD and histological grade of tumour. It is possible that MVD is the histopathological basis of early contrast enhancement of bladder cancer.

Expression of Cathepsin B and microvascular density increases with higher grade of astrocytomas

Samples were taken from supratentorial gliomas border and normal brain autopsy which were divided into four groups, these including eight cases normal brain tissues, 30 cases of astrocytomas, 25 cases of anaplastic astrocytomas and 22 cases of glioblastomas. Cathepin B (CB) expression and microvessel density (MVD) were determined with immunohistochemical studies. Staining results of CB was scored according to the percentage of positive cells, graded as negative (-), weak (+), moderate (++), and strong (+ + +). MVD was analyzed by Weidner's revised technique. CB positive staining was negative in eight cases of normal brain tissue. Only 9 out of 30 cases of astrocytomas showed a low percentage of positive cells that were stained in a light, diffuse cytoplasmic pattern (score +). Twenty-two out of 35 cases of anaplastic astrocytomas showed positive light, granular staining pattern, it including five samples (score +), and 17 samples (score + +). In contrast, all 22 cases of glioblastomas were stained all, and it was present in a course, granular staining pattern with an intensity of score (+ +) of two sample, and score (+ + +) of 20 samples. Positive staining tumor cells were found in extracellular matrix (ECM), basement membrane (BM), and the endothelial cells of blood vessels were also positive stained. Along with elevating glioma grade, CB expression and MVD value were both increased. Therefore, it showed MVD value was positive correlated with expression of CB. It highly suggested that CB and angiogenesis plays an important role in glioma progression.

Microvessel density and clinicopathological characteristics in hepatitis C virus and hepatitis B virus related hepatocellular carcinoma

Aims: To compare intratumorous microvessel density (MVD) and clinicopathological features in two different groups of hepatocellular carcinoma (HCC), namely: hepatitis B virus (HBV) related HCC (B-HCC) and HCV related HCC...

Prognostic value of VEGF expression in primary esophageal squamous cell carcinoma

Objective: To study the expression of vascular endothelial growth factor (VEGF) and microvessel density (MVD) in esophageal squamous cell carcinoma (ESCC) and clarify the association of VEGF expression with the angiogenesis and prognostic value of this disease. Methods: Eighty-two cases with primary ESCC treated with radical operation in Department of Surgery from Jan 1981 through May 1994 were enrolled. VEGF expression and MVD value were examined by immunohistochemical staining, the streptavidin-biotin peroxidase complex method (SP method), using anti-VEGF polyclonal antibody and anti-Factor-VIII antibody, respectively. We also analyzed the relationship between VEGF expression and MVD value and postoperative survival rate of patients. Results: Of the 82 cases, 63.4% cases showed positive for VEGF in tumor cells and the median of MVD in tumor was 37 (9–150) ·mm−2. There was a close correlation between MVD and VEGF (P=0.001). The 5-year survival rate of patients with low and high MVD was 34.1% and 12.2%, respectively. The 5-year survival rate was 46.7% in patients with VEGF-negative tumor and 11.5% in patients with VEGF-positive tumor. These differences were statistically significant (P=0.017 and P<0.001, respectively). Conclusion: In ESCC, angiogenesis is mediated mainly by VEGF and VEGF may be associated with tumor progression and increased malignancy via angiogenesis.

Expression of the angopoietin-1, angopoietin-2, Tie2, and vascular endothelial growth factor gene in epithelial ovarian cancer

Objective. Angiopoietin/Tie2 system with vascular endothelial growth factor (VEFG) is known to be important for the initiation of angiogenesis in tumors. The aim was to evaluate whether angiopoietin/Tie2 system with VEFG affects prognosis in patients of epithelial ovarian cancer. Methods. Angiopoietin-1 ( Ang-1), Angiopoietin-2 ( Ang-2), Tie2, and VEGF gene expression were analyzed by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) in 85 epithelial ovarian cancer surgical specimens. These gene expressions were correlated with clinical–pathological parameters, microvessel density (MVD), and patients' survival. Results. Ang-1/Ang-2 gene expression ratio, VEGF, and Tie2 gene expression significantly associated with MVD, respectively ( P < 0.0001, P = 0.024, P = 0.005). The patients with low Ang-1/Ang-2 gene expression ratio and high VEGF gene expression were found to have a significantly higher MVD when compared to others ( P = 0.0003). Moreover, there was a significant difference between the values of MVD in patients with low Ang-1/Ang-2 gene expression ratio and high VEGF and high Tie2 gene expression and those in others ( P = 0.0025). FIGO stage ( P = 0.014), residual disease ( P = 0.042), histological grade ( P = 0.028), Ang-1/Ang-2 gene expression ratio ( P = 0.010), and combination of Ang-1/Ang-2 gene expression ratio and VEGF gene expression ( P = 0.019), were found to be significantly associated with a poor prognosis in univariate Cox regression analysis. Multivariate Cox regression analysis revealed that FIGO stage is an independent prognostic factor ( P = 0.035). Low Ang-1/Ang-2 gene expression ratio had a tendency to be an independent prognostic factor ( P = 0.061). Conclusion. Angiogenesis occurred by angiopoietin/Tie2 system in concert with VEGF in epithelial ovarian cancer did not affect patients' survival. However, gene expression of Ang-1 and Ang-2 might present a pertinent diagnostic tool to select a high-risk group of patients independent of clinical–pathological parameters and a new insight to understand the biology of epithelial ovarian cancer.

P53 and VEGF expression are independent predictors of tumour recurrence and survival following curative resection of gastric cancer.

This study was undertaken to determine the value of tumour microvessel density (MVD) and the expression of p53 and vascular endothelial growth factor (VEGF) as prognostic markers in patients with gastric cancer operated on for cure. In all, 156 patients with curatively resected gastric cancer constituted the basis of this blinded retrospective evaluation. Patients were treated with either surgery alone (n=53) or surgery plus adjuvant chemotherapy (n=103). Tumour MVD, p53 expression, and VEGF expression were assayed using immunohistochemical techniques. After a mean follow-up of 43 months, 64 (41%) patients had died and 55 (35%) patients developed tumour recurrence. Positive correlations between MVD and both p53 (P=0.005) and VEGF (P=0.005) expression were observed. Both MVD ⩾100 (P=0.05) and positive VEGF expression (P<0.02) were associated with shorter disease-free survival, and positive VEGF expression (P=0.01) was also associated with shorter overall survival. Multivariate analysis confirmed that, in addition to the pathological tumour stage, lymph node ratio, the extent of lymphadenectomy and perineural invasion, p53 expression, and VEGF expression were independently associated with both disease-free survival (P<0.0005 and 0.02, respectively) and overall survival (P<0.02 and 0.01, respectively). Finally, patients whose tumours did not show p53 expression had a survival benefit compared to those expressing p53 when treated with adjuvant chemotherapy (P=0.01).This investigation demonstrates that p53 expression and VEGF expression are independent prognostic factors for both disease-free survival and overall survival in patients with curatively resected gastric cancer, and that p53 status may also influence response to chemotherapy.

Prognostic value of microvessel density in invasive ductal carcinoma of the breast.

Although the prognostic value of microvessel density (MVD) has been studied in breast cancer, the results still remain controversial. Paraffin embedded sections of invasive ductal carcinoma of the breast were immunohistochemically stained for factor VIII- related antigen in 252 patients with a median follow-up duration of 7.0 years. MVD quantification of the three most vascular areas at a magnification of x 200 was performed. The 252 patients were stratified into high and low MVD groups according to a cut-off value that was the upper one-third MVD value of all patients. The patients with a high MVD had a significantly worse outcome in terms of both disease free survival (DFS) (p< 0.0001) and overall survival (OS) (p= 0.0012) compared with those with a low MVD. The same effects were seen in patients with lymph node negative as well as positive breast cancer. Multivariate analyses indicated the nodal status, nuclear grade and MVD (p= 0.0001) to be independent prognostic factors for the DFS, while the nodal status, estrogen receptor status, tumor size and MVD (p= 0.0006) were independent prognostic factors for the OS. MVD was found to be an independent prognostic indicator of recurrence and death for breast cancer, and is therefore considered to be a useful factor for selecting high risk patients to receive adjuvant therapies.