Quantification of angiogenesis by the Chalkley method and its prognostic significance in epithelial ovarian cancer

Head-to-head comparisons of 68Ga-PSMA-11 and 18F-FDG PET/CT in evaluating patients with upper tract urothelial carcinoma: a prospective pilot study

PURPOSE

To prospectively compare the uptake of 68Ga-prostate specific membrane antigen (68Ga-PSMA)-11 and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in upper tract urothelial carcinoma (UTUC) and investigate the correlation between radiological parameters and pathological features of UTUC.

METHODS

Clinicopathologic and imaging data were collected from 10 UTUC patients who underwent preoperative 68Ga-PSMA-11 and 18F-FDG PET/CT scans. The diagnostic capabilities of both imaging techniques were analyzed and compared in UTUC. Angiogenesis in the malignancies was assessed using Chalkley counting and the expression of folate hydrolase 1 (FOLH1) and glucose transporter 1 (GLUT1) in UTUC were evaluated in the surgical specimens. Double immunofluorescence staining of PSMA and CD34 was used to examine tumor neovascularization. Tracer uptake and expression were compared and explored. Additionally, 10 patients with clear cell renal cell carcinoma (ccRCC) were included for prospective, comparative research.

RESULTS

Ten UTUC patients with 12 malignant lesions and another 10 ccRCC patients were included. 18F-FDG PET/CT demonstrated a more effective detection of UTUC foci compared to 68Ga-PSMA-11 PET/CT (the SUVmax of 18.48 ± 6.73 vs. 4.38 ± 1.45, P < 0.01). Immunohistochemical analysis revealed a statistically significant difference in the expression of PSMA and GLUT1 in UTUC (P = 0.048), with higher pathological grades showing more intense GLUT1 staining than PSMA (75% vs. 12.5%). The Chalkley counting of angiogenesis in ccRCC was significantly higher than that in UTUC (229.34 vs. 71.67), which was proportional to 68Ga-PSMA-11 PET/CT SUVmax (both P < 0.05).

CONCLUSION

18F-FDG PET/CT holds better clinical potential for evaluating UTUC and detecting lymph node metastasis compared to 68Ga-PSMA-11 PET/CT, likely due to the relatively scant expression of FOLH1 in tumor neovascular endothelium while the abundant expression of GLUT1 in malignancy. Furthermore, the lower neovascular density in UTUC should not be overlooked.

Evolving applications of the egg: chorioallantoic membrane assay and ex vivo organotypic culture of materials for bone tissue engineering

The chick chorioallantoic membrane model has been around for over a century, applied in angiogenic, oncology, dental and xenograft research. Despite its often perceived archaic, redolent history, the chorioallantoic membrane assay offers new and exciting opportunities for material and growth factor evaluation in bone tissue engineering. Currently, superior/improved experimental methodology for the chorioallantoic membrane assay are difficult to identify, given an absence of scientific consensus in defining experimental approaches, including timing of inoculation with materials and the analysis of results. In addition, critically, regulatory and welfare issues impact upon experimental designs. Given such disparate points, this review details recent research using the ex vivo chorioallantoic membrane assay and the ex vivo organotypic culture to advance the field of bone tissue engineering, and highlights potential areas of improvement for their application based on recent developments within our group and the tissue engineering field.

Prognostic value of the area and density of lymphatic vessels in cutaneous squamous cell carcinoma

BACKGROUND AND OBJECTIVES

Cutaneous squamous cell carcinoma (SCC) is known for its capacity to metastasize via lymphatic vessels. In recent studies, the level of lymphangiogenesis has been reported as a potential prognostic factor for several skin tumors. The aim of this study was to quantify lymphangiogenesis in SCC using either computer-assisted image analysis or the Chalkley count technique. Vascular parameters were evaluated and compared with respect to their predictive power for tumor metastasis.

PATIENT AND METHODS

In this case-control study, clinical and histological data of 15 metastatic and 15 nonmetastatic SCC patients were retrospectively analyzed. SCC samples were immunostained for the lymphatic endothelial marker D2-40 and the panvascular marker CD31, and analyzed using computer-assisted morphometric image analyses within hot spots as well as the digitalized Chalkley counting method.

RESULTS

Lymphatic vessel density, relative lymphatic vessel area, and lymphatic Chalkley count were significantly elevated in metastatic SCC. Tumor thickness was significantly higher in metastatic SCC, and had the highest predictive power for metastatic disease. Tumor thickness was a significant predictor of lymphangiogenic parameters.

CONCLUSIONS

Lymphangiogenesis is elevated in metastatic SCC but its extent is influenced by tumor thickness. Tumor thickness remains the most reliable predictive factor for metastatic disease.

Overexpression of the chimeric plasmin-resistant VEGF165/VEGF183 (132-158) protein in murine breast cancer induces distinct vascular patterning adjacent to tumors and retarded tumor growth

A chimeric plasmin‑resistant vascular endothelial growth factor (VEGF)165/VEGF183 (132-158) protein, named as VEGF183 (according to the nomenclature of VEGF), designed by a previous study, was demonstrated to have an enhanced affinity for the extracellular matrix (ECM) amongst other bioactivities. However, it is now accepted that mutant VEGFs frequently demonstrate different angiogenic activities and produce different vascular patterning from the parental molecule. The present study hypothesized that VEGF183, due to its enhanced binding affinity to the ECM, would exhibit a different angiogenic activity and produce a different vascular patterning compared to those of VEGF165. Murine breast cancer EMT‑6 cells were manipulated to stably overexpress VEGF165 or VEGF183. These cells were then inoculated intradermally into BALB/c mice in order to monitor the formation of vascular patterning in skin proximal to tumors. In vivo angiogenesis experiments revealed that overexpression of VEGF183 in murine breast cancer cells resulted in irregular, disorganized and dense vascular patterning as well as induced a significant inhibition of tumor growth compared with that of VEGF165. In addition, allograft tumor immunochemical assays of VEGF183‑overexpressing tumors demonstrated significantly lower vascular densities than those of VEGF165‑overexpressing tumors; however, VEGF183 tumors had a significantly enlarged vascular caliber. Conversely, cell wound healing experiments revealed that VEGF183‑overexpressing EMT‑6 cells had significantly decreased migration rates compared with those of VEGF165‑overexpressing EMT‑6 cells. In conclusion, the results of the present study supported the hypothesis that the altered ECM affinity of VEGF induced structural alterations to vasculature. In addition, these results provided a novel insight into VEGF design and indirect evidence for the function of exon 8 in VEGF. [Corrected]

Chalkley method in the angiogenesis research and its automation via computer simulation

The aim of this study was to develop a computer simulation evaluating microvessel density according to the Chalkley method on digital images taken from neovascular hot spots. An image analysis algorithm has been developed using ImageJ, an extensible, open source image processing and analysis software. The idea was to create a virtual Chalkley point array graticule, and to calculate Chalkley counts automatically by stepwise angular rotation of it on the superimposed images containing properly segmented microvessels. This eliminates the necessity of having the Chalkley graticule, an accessory that has to be mounted on the microscope's ocular. The proposed method is a faithful simulation of the original Chalkley counting procedure. It gives pathologists who do not have the Chalkley graticule an opportunity to evaluate microvessels quantitatively according to the basic principles underlying Chalkley counting. Evaluating microvessel densities in solid tumors is a frequent procedure in angiogenesis research. A few standard methods, including Chalkley counting, are used for the estimation of microvessel density. Several independent studies have shown that the Chalkley counting is more consistent and may provide useful data on prognosis. The obvious disadvantages lie in the facts that this method is time-consuming and requires a special hardware. Computer simulation may overcome these obstacles.

A microRNA signature defines chemoresistance in ovarian cancer through modulation of angiogenesis

Epithelial ovarian cancer is the most lethal gynecologic malignancy; it is highly aggressive and causes almost 125,000 deaths yearly. Despite advances in detection and cytotoxic therapies, a low percentage of patients with advanced stage disease survive 5 y after the initial diagnosis. The high mortality of this disease is mainly caused by resistance to the available therapies. Here, we profiled microRNA (miR) expression in serous epithelial ovarian carcinomas to assess the possibility of a miR signature associated with chemoresistance. We analyzed tumor samples from 198 patients (86 patients as a training set and 112 patients as a validation set) for human miRs. A signature of 23 miRs associated with chemoresistance was generated by array analysis in the training set. Quantitative RT-PCR in the validation set confirmed that three miRs (miR-484, -642, and -217) were able to predict chemoresistance of these tumors. Additional analysis of miR-484 revealed that the sensitive phenotype is caused by a modulation of tumor vasculature through the regulation of the VEGFB and VEGFR2 pathways. We present compelling evidence that three miRs can classify the response to chemotherapy of ovarian cancer patients in a large multicenter cohort and that one of these three miRs is involved in the control of tumor angiogenesis, indicating an option in the treatment of these patients. Our results suggest, in fact, that blockage of VEGF through the use of an anti-VEGFA antibody may not be sufficient to improve survival in ovarian cancer patients unless VEGFB signaling is also blocked.

Cancer-associated fibroblasts and their putative role in potentiating the initiation and development of epithelial ovarian cancer

The progression of ovarian cancer, from cell transformation through invasion of normal tissue, relies on communication between tumor cells and their adjacent stromal microenvironment. Through a natural selection process, an autocrine-paracrine communication loop establishes reciprocal reinforcement of growth and migration signals. Thus, the cancer-activated stromal response is similar to an off-switch-defective form of the normal, universal response needed to survive insult or injury. It is becoming clearer within the cancer literature base that tumor stroma plays a bimodal role in cancer development: it impedes neoplastic growth in normal tissue while encouraging migration and tumor growth in a co-opted desmoplastic response during tumor progression. In this review, we discuss this reciprocal influence that ovarian cancer epithelial cells may have on ovarian stromal cell-reactive phenotype, stromal cell behavior, disrupted signaling networks, and tumor suppressor status in the stroma, within the context of cancer fibroblast studies from alternate cancer tissue settings. We focus on the exchange of secreted factors, in particular interleukin 1β and SDF-1α, between activated fibroblasts and cancer cells as a key area for future investigation and therapeutic development. A better understanding of the bidirectional reliance of early epithelial cancer cells on activated stromal cells could lead to the identification of novel diagnostic stromal markers and targets for therapy.

A Phase II, open-label study evaluating pazopanib in patients with recurrent ovarian cancer

OBJECTIVE

The progression-free and median survival of patients with advanced ovarian cancer has not appreciably improved over the last decade. Novel targeted therapies, particularly antiangiogenic agents, may potentially improve clinical outcomes in patients with ovarian cancer. This phase II, open-label study evaluated oral pazopanib monotherapy in patients with low-volume recurrent ovarian cancer.

METHODS

Patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal carcinoma with complete CA-125 response to initial platinum-based chemotherapy and subsequent elevation of CA-125 to ≥ 42 U/mL (> 2 × ULN) were treated with pazopanib 800 mg once daily until PD or unacceptable toxicity. This Green-Dahlberg study required 2 CA-125 responses in stage I (20 patients) to proceed to stage II (15 patients). The primary endpoint was CA-125 response (≥ 50% decrease from baseline, confirmed ≥ 21 days after initial evaluation).

RESULTS

Eleven of 36 patients (31%) had a CA-125 response to pazopanib, with median time to response of 29 days and median response duration of 113 days. Overall response rate was 18% in patients with measurable disease at baseline. The most common adverse events leading to discontinuation of study drug were grade 3 ALT (8%) and AST (8%) elevation. Only 1 grade 4 toxicity (peripheral edema) was reported.

CONCLUSIONS

Pazopanib monotherapy was relatively well tolerated, with toxicity similar to other small-molecule, oral angiogenesis inhibitors, and demonstrated promising single-agent activity in patients with recurrent ovarian cancer. Further studies evaluating the potential role of pazopanib in patients with ovarian cancer are ongoing.

Predictive and prognostic protein biomarkers in epithelial ovarian cancer: recommendation for future studies

Epithelial ovarian cancer is the most lethal gynecological malignancy. Due to its lack of symptoms, this disease is diagnosed at an advanced stage when the cancer has already spread to secondary sites. While initial rates of response to first treatment is >80%, the overall survival rate of patients is extremely low, mainly due to development of drug resistance. To date, there are no reliable clinical factors that can properly stratify patients for suitable chemotherapy strategies. Clinical parameters such as disease stage, tumor grade and residual disease, although helpful in the management of patients after their initial surgery to establish the first line of treatment, are not efficient enough. Accordingly, reliable markers that are independent and complementary to clinical parameters are needed for a better management of these patients. For several years, efforts to identify prognostic factors have focused on molecular markers, with a large number having been investigated. This review aims to present a summary of the recent advances in the identification of molecular biomarkers in ovarian cancer patient tissues, as well as an overview of the need and importance of molecular markers for personalized medicine in ovarian cancer.

Stromal compartment as a survival prognostic factor in advanced ovarian carcinoma

OBJECTIVE

We investigated the prognostic significance of stromal compartment on the overall survival of patients with advanced epithelial ovarian cancer.

METHODS

We evaluated retrospectively the stroma proportion of the tumor surgical specimens of 194 patients with stages III and IV disease, using histochemical staining and fully automatic virtual slide processing. The prognostic significance of stroma proportion and clinical parameters were evaluated using log-rank test and Cox regression.

RESULTS

Stroma proportion was found to be an independent prognostic factor by both univariate (P = 0.016) and multivariate analyses (hazards ratio = 1.45, P = 0.011).

CONCLUSION

The present data indicate that a high stroma proportion is related to a poor prognosis of stage III and IV ovarian carcinomas.

First-line treatment of advanced ovarian cancer: current research and perspectives

Epithelial ovarian cancer is the fourth biggest cause of cancer-related death in women. Over recent decades, improvements have been made in treatment outcome in terms of response rate and survival. To date, intensive surgical staging and cytoreduction, followed by primary chemotherapy with the carboplatin-paclitaxel regimen, are considered the gold standard for the management of this disease. Nevertheless, despite good initial response to systemic therapy after optimal debulking surgery, the long-term survival remains poor, with a high risk of recurrence. Furthermore, medical therapy of ovarian cancer impacts quality of life owing to the common occurrence of chemotherapy side effects, such as alopecia, neurotoxicity and fatigue. In order to improve the efficacy and reduce the toxicity of first-line chemotherapy, more than 10,000 women have been involved in worldwide randomized trials in the last 10 years. Several treatment alternatives have been investigated, such as intraperitoneal chemotherapy, alternative doublets and triplet regimens, in the effort to find an optimal first-line treatment strategy. In this review we discuss the results of these trials, the recent progresses and the most important ongoing studies, including those with emerging target and biological agents.

Antivascular therapy for epithelial ovarian cancer

Ovarian cancer is the fifth largest cancer killer in women. Improved understanding of the molecular pathways implicated in the pathogenesis of ovarian cancer has led to the investigation of novel targeted therapies. Ovarian cancer is characterized by an imbalance between pro- and antiangiogenic factors in favor of angiogenesis activation. Various antivascular strategies are currently under investigation in ovarian cancer. They can schematically be divided into antiangiogenic and vascular-disrupting therapies. This paper provides a comprehensive review of these new treatments targeting the tumor vasculature in this disease. Promising activities have been detected in phase II trials, and results of phase III clinical trials are awaited eagerly.

Computer-aided Image Processing of Angiogenic Histological

This article reviews the questions regarding the image evaluation of angiogeneic histological samples, particularly the ovarian epithelial cancer. Review is focused on the principles of image analysis in the field of histology and pathology. The definition, classification, pathogenesis and angiogenesis regulation in the ovaries are also briefly discussed. It is hoped that the complex image analysis together with the patient's clinical parameters will allow an acquiring of a clear pathogenic picture of the disease, extension of the differential diagnosis and become a useful tool for the evaluation of drug effects. The challenge of the assessment of angiogenesis activity is the heterogeneity of several objects: parameters derived from patient's anamnesis as well as of pathology samples. The other unresolved problems are the subjectivity of the region of interest selection and performance of the whole slide scanning.

KEYWORDS

Angiogenesis; Image processing; Microvessel density; Cancer; Pathology.

VEGF-A and i-NOS expression are prognostic factors in serous epithelial ovarian carcinomas after complete surgical resection

AIMS

Clinical stage at the time of diagnosis and achievement of complete macroscopic resection during initial surgery are key factors determining the outcome of ovarian cancer. However, prediction of outcome lacks accuracy and more reliable prognostic factors are required. Therefore, an analysis and evaluation of key angiogenic factors was carried out to determine their diagnostic and prognostic value in serous ovarian cancer.

METHODS

Expression levels of vascular endothelial growth factor (VEGF)-A, hypoxia-inducible factor (HIF)1-alpha and inducible nitric oxide synthase (i-NOS) were analysed by immunohistochemistry in a homogenous group of 112 patients with serous adenocarcinoma of the ovary. Vascular density as an indicator of angiogenesis was assessed using the Chalkley eyepiece method after staining for CD34. The correlation of these data with survival and established prognostic factors such as histological grade, Federation of Gynecology and Obstetrics (FIGO) stage, and residual tumour after surgery, was evaluated. Survival analyses, multivariate analyses and correlation tests were performed.

RESULTS

In the patient group with macroscopic complete tumour resection (R0) there was a significant correlation between VEGF-A and i-NOS expression. Kaplan-Meier analysis further revealed improved progression-free survival for R0 patients with VEGF-A-positive and i-NOS-negative tumours. The predictive relevance of VEGF-A regarding progression-free survival was sustained in multivariate analysis using FIGO stage, grading and resection status as fixed variables.

CONCLUSION

VEGF-A and i-NOS are prognostic markers for clinical outcome in serous ovarian cancer patients with macroscopic complete tumour resection (R0). Hence, pre-therapeutic assessment of VEGF-A as predictive factor for an antiangiogenic therapy might be of clinical value.