Neoadjuvant chemotherapy induces an elevation of tumour apparent diffusion coefficient values in patients with ovarian cancer.

OBJECTIVES: Multiparametric magnetic resonance imaging (mMRI) is the modality of choice in the imaging of ovarian cancer (OC). We aimed to investigate the feasibility of different types of regions of interest (ROIs) in the measurement of apparent diffusion coefficient (ADC) values of diffusion-weighted imaging in OC patients treated with neoadjuvant chemotherapy (NACT). METHODS: We retrospectively enrolled 23 consecutive patients with advanced OC who had undergone NACT and mMRI. Seventeen of them had been imaged before and after NACT. Two observers independently measured the ADC values in both ovaries and in the metastatic mass by drawing on a single slice of (1) freehand large ROIs (L-ROIs) covering the solid parts of the whole tumour and (2) three small round ROIs (S-ROIs). The side of the primary ovarian tumour was defined. We evaluated the interobserver reproducibility and statistical significance of the change in tumoural pre- and post-NACT ADC values. Each patient's disease was defined as platinum-sensitive, semi-sensitive, or resistant. The patients were deemed either responders or non-responders. RESULTS: The interobserver reproducibility of the L-ROI and S-ROI measurements ranged from good to excellent (ICC range: 0.71-0.99). The mean ADC values were significantly higher after NACT in the primary tumour (L-ROI p < 0.001, S-ROIs p < 0.01), and the increase after NACT was associated with sensitivity to platinum-based chemotherapy. The changes in the ADC values of the omental mass were associated with a response to NACT. CONCLUSION: The mean ADC values of the primary tumour increased significantly after NACT in the OC patients, and the amount of increase in omental mass was associated with the response to platinum-based NACT. Our study indicates that quantitative analysis of ADC values with a single slice and a whole tumour ROI placement is a reproducible method that has a potential role in the evaluation of NACT response in patients with OC. TRIAL REGISTRATION: Retrospectively registered (institutional permission code: 5302501; date of the permission: 31.7.2020).

Expression profiles of VEGF-A, VEGF-D and VEGFR1 are higher in distant metastases than in matched primary high grade epithelial ovarian cancer.

BACKGROUND: In many malignancies including ovarian cancer, different angiogenic factors have been related to poor prognosis. However, data on their relations to each other or importance as a prognostic factor in ovarian cancer is missing. Therefore, we investigated the expressions of VEGF-A, VEGF-C, and VEGF-D, and the receptors VEGFR1, VEGFR2, and VEGFR3 in patients with malignant epithelial ovarian neoplasms. We further compared expression levels between primary tumors and related distant omental metastases. METHODS: This study included 86 patients with malignant ovarian epithelial tumors and 16 related distant metastases. Angiogenic factor expression was evaluated using immunohistochemistry (n = 102) and qRT-PCR (n = 29). RESULTS: Compared to primary high grade serous ovarian tumors, the related omental metastases showed higher expressions of VEGF-A (p = 0.022), VEGF-D (p = 0.010), and VEGFR1 (p = 0.046). In univariate survival analysis, low epithelial expression of VEGF-A in primary tumors was associated with poor prognosis (p = 0.024), and short progression-free survival was associated with high VEGF-C (p = 0.034) and low VEGFR3 (p = 0.002). The relative expressions of VEGF-D, VEGFR1, VEGFR2, and VEGFR3 mRNA determined by qRT-PCR analyses were significantly correlated with the immunohistochemically detected levels of these proteins in primary high grade serous ovarian cancer and metastases (p = 0.004, p = 0.009, p = 0.015, and p = 0.018, respectively). CONCLUSIONS: The expressions of VEGF receptors and their ligands significantly differed between malignant ovarian tumors and paired distant metastases. VEGF-A, VEGF-D, and VEGFR1 protein expressions seem to be higher in distant metastases than in the primary high grade serous ovarian cancer lesions.

Primary and metastatic ovarian cancer: Characterization by 3.0T diffusion-weighted MRI.

OBJECTIVES: We aimed to investigate whether apparent diffusion coefficients (ADCs) measured by 3.0T diffusion-weighted magnetic resonance imaging (DWI) associate with histological aggressiveness of ovarian cancer (OC) or predict the clinical outcome. This prospective study enrolled 40 patients with primary OC, treated 2011-2014. METHODS: DWI was performed prior to surgery. Two observers used whole lesion single plane region of interest (WLsp-ROI) and five small ROIs (S-ROI) to analyze ADCs. Samples from tumours and metastases were collected during surgery. Immunohistochemistry and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to measure the expression of vascular endothelial growth factor (VEGF) and its receptors. RESULTS: The interobserver reliability of ADC measurements was excellent for primary tumours ICC 0.912 (WLsp-ROI). Low ADCs significantly associated with poorly differentiated OC (WLsp-ROI P = 0.035). In primary tumours, lower ADCs significantly associated with high Ki-67 (P = 0.001) and low VEGF (P = 0.001) expression. In metastases, lower ADCs (WLsp-ROI) significantly correlated with low VEGF receptors mRNA levels. ADCs had predictive value; 3-year overall survival was poorer in patients with lower ADCs (WLsp-ROI P = 0.023, S-ROI P = 0.038). CONCLUSION: Reduced ADCs are associated with histological severity and worse outcome in OC. ADCs measured with WLsp-ROI may serve as a prognostic biomarker of OC. KEY POINTS: • Reduced ADCs correlate with prognostic markers: poor differentiation and high Ki-67 expression • ADCs also significantly correlated with VEGF protein expression in primary tumours • Lower ADC values are associated with poorer survival in ovarian cancer • Whole lesion single plane-ROI ADCs may be used as a prognostic biomarker in OC.

Combined Gene Therapy Using AdsVEGFR2 and AdsTie2 With Chemotherapy Reduces the Growth of Human Ovarian Cancer and Formation of Ascites in Mice.

OBJECTIVES: Ovarian cancer is highly dependent on tumor microvessels and angiogenesis regulated by vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) and angiopoietins (Ang) and their Tie receptors. We studied the efficacy of adenoviral (Ad) gene therapy with soluble VEGFR2 and Tie2 combined with paclitaxel and carboplatin for the treatment of ovarian cancer. METHODS: An intraperitoneal human ovarian cancer xenograft model in nude mice (n = 44) was used in this study. Gene therapy was given intravenously when the presence of sizable tumors was confirmed in magnetic resonance imaging. The study groups were as follows: AdCMV as a control (group I), AdCMV with chemotherapy (group II), AdsVEGFR2 and AdsTie2 (group III), and AdsVEGFR2 and AdsTie2 with chemotherapy (group IV). Antitumor effectiveness was assessed by overall tumor growth, ascites, immunohistochemistry, microvessel density, and sequential magnetic resonance imaging analyses. RESULTS: AdsVEGFR2 and AdsTie2 gene therapy (group III) significantly reduced tumor weights as compared with group II (P = 0.007). Accumulation of ascites was significantly reduced when the mice were treated with AdsVEGFR2 and AdsTie2 gene therapy or with combined gene therapy and chemotherapy as compared with controls (P = 0.029 and P = 0.010, respectively). Vascular endothelial growth factor and Ang2 levels in ascites fluid were elevated after the gene therapy. CONCLUSIONS: Combined inhibition of VEGF/VEGFR2 and Ang/Tie2 pathways provided efficient therapy for ovarian cancer in mice. In addition, antiangiogenic gene therapy has potential as a treatment for the accumulation of ascites.

Serum angiopoietin-2 and soluble VEGFR-2 levels predict malignancy of ovarian neoplasm and poor prognosis in epithelial ovarian cancer.

BACKGROUND: The aim of the study was to explore the serum levels of eight angiogenesis biomarkers in patients with benign, borderline or malignant epithelial ovarian neoplasms and to compare them to those of healthy controls. In addition, we aimed to study how those biomarkers predict the clinical course and survival of patients with epithelial ovarian cancer. METHODS: We enrolled 132 patients with ovarian neoplasms and 32 unaffected women in this study. Serum samples were collected preoperatively at the time of diagnosis and the levels of angiogenesis biomarkers were measured with an ELISA. RESULTS: Levels of Ang-1, Ang-2, VEGF, VEGF-D, VEGF/sVEGFR-2 and Ang-2/ sVEGFR-2 ratios were elevated whereas sVEGFR-2 was lower in patients with ovarian carcinoma than in women with normal ovaries, benign and/or borderline ovarian neoplasms. In ROC analysis, the area under the curve for serum Ang-2/sVEGFR-2 ratio (0.76) was greater than Ang-2 (0.75) and VEGF (0.65) but lower than for CA 125 (0.90) to differentiate ovarian cancer from benign or borderline ovarian tumors. In ovarian cancer high Ang-2/sVEGFR-2 ratio was associated with the presence of ascites, high stage and grade of ovarian cancer, with the size of primary residual tumor>1 cm and with recurrence of disease. Elevated Ang-2, VEGF, VEGF/sVEGFR-2, Ang-2/VEGF and Ang-2/sVEGFR-2 ratios and low level of sVEGFR-2 were significant predictors of poor overall survival (OS) and recurrence free survival (RFS) in univariate survival analyses. CONCLUSIONS: Ovarian cancer patients had elevated levels of angiogenesis related growth factors in circulation reflecting increased angiogenesis and poor prognosis. The serum level of Ang-2 predicted most accurately poor OS and Ang-2/sVEGFR-2 ratio malignancy of ovarian neoplasms and short RFS.

Dynamic contrast-enhanced MRI to characterize angiogenesis in primary epithelial ovarian cancer: An exploratory study.

PURPOSE: Angiogenesis is essential for tumor growth. Currently, there are no established imaging biomarkers to show angiogenesis in tumor tissue. The aim of this prospective study was to evaluate whether semiquantitative and pharmacokinetic DCE-MRI perfusion parameters could be used to assess angiogenesis in epithelial ovarian cancer (EOC). METHOD: We enrolled 38 patients with primary EOC treated in 2011-2014. DCE-MRI was performed with a 3.0 T imaging system before the surgical treatment. Two different sizes of ROI were used to evaluate semiquantitative and pharmacokinetic DCE perfusion parameters: a large ROI (L-ROI) covering the whole primary lesion on one plane and a small ROI (S-ROI) covering a small solid, highly enhancing focus. Tissue samples from tumors were collected during the surgery. Immunohistochemistry was used to measure the expression of vascular endothelial growth factor (VEGF), its receptors (VEGFRs) and to analyse microvascular density (MVD) and the number of microvessels. RESULTS: VEGF expression correlated inversely with Ktrans (L-ROI, r = -0.395 (p = 0.009), S-ROI, r = -0.390, (p = 0.010)), Ve (L-ROI, r = -0.395 (p = 0.009), S-ROI, r = -0.412 (p = 0.006)) and Vp (L-ROI, r = -0.388 (p = 0.011), S-ROI, r = -0.339 (p = 0.028)) values in EOC. Higher VEGFR-2 correlated with lower DCE parameters Ktrans (L-ROI, r = -0.311 (p = 0.040), S-ROI, r = -0.337 (p = 0.025)) and Ve (L-ROI, r = -0.305 (p = 0.044), S-ROI, r = -0.355 (p = 0.018)). We also found that MVD and the number of microvessels correlated positively with AUC, Peak and WashIn values. CONCLUSIONS: We observed that several DCE-MRI parameters correlated with VEGF and VEGFR-2 expression and MVD. Thus, both semiquantitative and pharmacokinetic perfusion parameters of DCE-MRI represent promising tools for the assessment of angiogenesis in EOC.

Antiangiogenic gene therapy with soluble VEGF-receptors -1, -2 and -3 together with paclitaxel prolongs survival of mice with human ovarian carcinoma.

We compared effects of antiangiogenic gene therapy with a combination of soluble sVEGFR-1, sVEGFR-2 and sVEGFR-3 to chemotherapy with carboplatin and paclitaxel and to antiangiogenic monoclonal anti-VEGF-antibody bevacizumab in an intraperitoneal ovarian cancer xenograft model in mice (n = 80). Gene therapy was also combined with chemotherapy. Therapy was initiated when sizable tumors were confirmed in magnetic resonance imaging (MRI). Adenovirus-mediated gene transfer was performed intravenously (2 × 109 pfu), while chemotherapy and monoclonal anti-VEGF-antibody were dosed intraperitoneally. The study groups were as follows: AdLacZ control (n = 21); combination of AdsVEGFR-1, -2 and -3 (n = 21); combination of AdsVEGFR-1, -2, -3 and paclitaxel (n = 9); bevacizumab (n = 14); paclitaxel (n = 9) and carboplatin (n = 5). Effectiveness was assessed by survival time and surrogate measures such as sequential MRI, immunohistochemistry, microvessel density and tumor growth. Antiangiogenic gene therapy combined with paclitaxel significantly prolonged the mean survival of mice (25 days) compared to the controls (15 days) and all other treatment groups (p = 0.001). Bevacizumab treatment did not have any significant effect on the survival. Tumors of the mice treated by gene therapy were significantly smaller than in the control group (p = 0.021). The mean vascular density and total vascular area were also significantly smaller in the tumors of the gene therapy group (p = 0.01). These results show potential of the antiangiogenic gene therapy to improve efficacy of chemotherapy with paclitaxel and support testing of this approach in a phase I clinical trial for the treatment of ovarian cancer.

AAV8-mediated sVEGFR2 and sVEGFR3 gene therapy combined with chemotherapy reduces the growth and microvasculature of human ovarian cancer and prolongs the survival in mice.

Background: Vascular endothelial growth factors (VEGFs) are major regulators of intratumoral angiogenesis in ovarian cancer (OVCA). Overexpression of VEGFs is associated with increased tumor growth and metastatic tendency and VEGF-targeting therapies are thus considered as potential treatments for OVCA. Here, we examined the antiangiogenic and antitumoral effects on OVCA of adeno-associated virus 8 (AAV8)-mediated expression of soluble VEGF receptors (sVEGFRs) sVEGFR2 and sVEGFR3 together with paclitaxel and carboplatin chemotherapy. Materials and methods: Immunodeficient mice were inoculated with human OVCA cell line SKOV-3m. Development of tumors was confirmed with magnetic resonance imaging (MRI) and mice were treated with gene therapy and paclitaxel and carboplatin chemotherapy. The study groups included (I) non-treated control group, (II) blank control vector AAV8-CMV, (III) AAV8-CMV with chemotherapy, (IV) AAV8-sVEGFR2, (V) AAV8-sVEGFR3, (VI) AAV8-sVEGFR2 and AAV8-sVEGFR3, and (VII) AAV8-sVEGFR2 and AAV8-sVEGFR3 with chemotherapy. Antiangiogenic and antitumoral effects were evaluated with immunohistochemical stainings and serial MRI. Results: Reduced intratumoral angiogenesis was observed in all antiangiogenic gene therapy groups. The combined use of AAV8-sVEGFR2 and AAV8-sVEGFR3 with chemotherapy suppressed ascites fluid formation and tumor growth, thus improving the overall survival of mice. Antitumoral effect was mainly caused by AAV8-sVEGFR2 while the benefits of AAV8-sVEGFR3 and chemotherapy were less prominent. Conclusion: Combined use of the AAV8-sVEGFR2 and AAV8-sVEGFR3 with chemotherapy reduces intratumoral angiogenesis and tumor growth in OVCA mouse model. Results provide preclinical proof-of-concept for the use of soluble decoy VEGFRs and especially the AAV8-sVEGFR2 in the treatment of OVCA.

Robotic-assisted laparoscopy is a feasible method for resection of deep infiltrating endometriosis, especially in the rectosigmoid area.

OBJECTIVE: This study aimed to compare outcomes of mini-invasive surgical treatment of endometriosis, especially conventional laparoscopy with robotic-assisted laparoscopy, and to evaluate the quality of life. METHODS: One hundred three consecutive patients with endometriosis who had surgery from 2014 to 2017 owing to an indication of pain were enrolled in this retrospective study. The majority (n = 77, 75%) of patients underwent conventional laparoscopy and 18 (17%) had robotic-assisted laparoscopy. The quality of life was postoperatively assessed with a questionnaire. RESULTS: The rates of parametrectomy (76% vs. 45%,) and rectovaginal resection (28% vs. 4%) were significantly higher in robotic-assisted laparoscopy than in laparoscopy. Additionally, the rate of bowel operations (50% vs. 17%), especially the shaving technique, was higher in robotic-assisted laparoscopy surgery than in laparoscopy (39% vs. 8%). There was no difference in the rate of postoperative complications between laparoscopy and robotic-assisted laparoscopy. Most (91%) of the patients who answered the questionnaire felt that surgical treatment had relieved their pain. In the laparoscopic and robotic-assisted groups, 88% of respondents felt that their quality of life had improved after surgery. CONCLUSIONS: This study suggests that robotic-assisted laparoscopy is a feasible method to resect deep infiltrating endometriosis, especially in the rectosigmoid area.

Preoperative angiopoietin-2 serum levels: a marker of malignant potential in ovarian neoplasms and poor prognosis in epithelial ovarian cancer.

INTRODUCTION: The aims of the study were to explore the levels of angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) in patients with benign, borderline, or malignant epithelial ovarian tumors and to compare them to those of healthy controls. In addition, we aimed to study how Ang-1 and Ang-2 levels predict the clinical course and survival of patients with epithelial ovarian cancer. METHODS: We enrolled 150 patients with ovarian neoplasms and 34 women with healthy ovaries in this study. Furthermore, we measured the levels of Ang-1 and Ang-2 in patients having an ovarian metastasis or another cancer (n = 29). Serum samples were collected preoperatively at the time of diagnosis, and Ang-1 and Ang-2 levels were measured with an enzyme-linked immunosorbent assay. RESULTS: Angiopoietin-1 and Ang-2 levels were significantly elevated in serum samples of patients with ovarian carcinoma compared with healthy controls (P = 0.0005 and P < 0.0005, respectively). In addition, Ang-2 levels were significantly higher in patients with ovarian carcinoma compared with patients with benign (P < 0.0005) or borderline ovarian tumors (P = 0.011). In receiver operating characteristic analysis, the area under the curve for serum Ang-2 (0.77) was greater than Ang-1 (0.60) but lower than for cancer antigen 125 (0.95) to differentiate ovarian cancer from healthy control. High serum levels of Ang-1 and Ang-2 were associated with primary residual tumor more than 1 cm after debulking surgery, and high Ang-2 levels correlated positively with an advanced tumor stage (P = 0.042). Elevated Ang-2 level (>2.7 ng/mL) was a significant predictor of poor overall and recurrence-free survival (P = 0.043 and P = 0.033, respectively) when assessing Kaplan-Meier curves by a log-rank test. CONCLUSIONS: Patients with ovarian cancer have higher serum levels of angiopoietins than patients with benign or borderline tumors reflecting the increased angiogenesis. These results also suggest that Ang-2 may serve as an angiogenic marker of decreased patient survival in ovarian cancer.

Antiangiogenic gene therapy with soluble VEGFR-1, -2, and -3 reduces the growth of solid human ovarian carcinoma in mice.

We studied antiangiogenic and antilymphangiogenic effects of sVEGFR-1 (sFlt-1), sVEGFR-2 (sFlk-1/KDR), and sVEGFR-3 (sFlt-4) gene transfers and their combinations in intraperitoneal ovarian cancer xenograft mice (Balb/c-Anu, n = 55). Gene therapy was initiated when the presence of sizable tumors was confirmed in magnetic resonance imaging (MRI). Adenovirus-mediated gene transfer was performed intravenously via tail vein as follows: AdLacZ as a control (group I), AdsFlt-1 (group II), AdsKDR (group III), AdsFlt-4 (group IV) and two combination groups of AdsFlt-1 and AdsFlt-4 (group V) and AdsFlt-1, AdsKDR, and AdsFlt-4 (group VI). Antitumor effectiveness was assessed by sequential MRI, immunohistochemistry, microvessel density, overall tumor growth, and survival time. In combination group VI, intraperitoneal tumors were significantly smaller than in the control group at the end of the follow-up (P < 0.001). Furthermore, in group VI the microvessel density (microvessels/mm(2)) in tumor tissue and the total area of tumors covered by microvessels were significantly smaller than in the controls. One mouse in group V was cured. The combined antiangiogenic gene therapy with soluble VEGFRs reduced tumor growth, tumor vascularity, and ascites formation in ovarian cancer xenografts. The results suggest that the combined antiangiogenic gene therapy is a potential approach for the treatment of ovarian cancer patients.

High expression of Tie-2 predicts poor prognosis in primary high grade serous ovarian cancer.

BACKGROUND: Antiangiogenic therapy, although part of standard treatment in ovarian cancer, has variable efficacy. Furthermore, little is known about the prognostic biomarkers and factors influencing angiogenesis in cancer tissue. We evaluated the expression of angiopoietin-2 and two endothelial tyrosine kinase receptors, Tie-1 and Tie-2, and assessed their value in the prediction of survival in patients with malignant epithelial ovarian cancer. We also compared the expression of these factors between primary high grade serous tumors and their distant metastasis. MATERIALS AND METHODS: We evaluated 86 women with primary epithelial ovarian cancer. Matched distal omental metastasis were investigated in 18.6% cases (N = 16). The expression levels of angiogenic factors were evaluated by immunohistochemistry in 306 specimens and by qRT-PCR in 111 samples. RESULTS: A high epithelial expression level of Tie-2 is a significant prognostic factor in primary high grade serous ovarian cancer. It predicted significantly shorter overall survival both in univariate (p<0.001) and multivariate survival analyses (p = 0.022). Low angiopoietin-2 expression levels in primary ovarian tumors were significantly associated with shorter overall survival (p = 0.015) in the univariate survival analysis. A low expression of angiopoietin-2 was also significantly related to high grade tumors, size of residual tumor after primary surgery and the recurrence of cancer (p = 0.008; p = 0.012; p = 0.018) in the whole study population. The expression of angiopoietin-2 and Tie-2 was stronger in distal omental metastasis than in primary high grade serous tumors in matched-pair analysis (p = 0.001; p = 0.002). CONCLUSIONS: The angiogenic factor, angiopoietin-2, and its receptor Tie-2 seem to be significant prognostic factors in primary epithelial ovarian cancer. Their expression levels are also increased in metastatic lesions in comparison with primary tumors.

Microvessels in Epithelial Ovarian Tumors: High Microvessel Density Is a Significant Feature of Malignant Ovarian Tumors.

BACKGROUND/AIM: Examine features of blood and lymphatic vessels in ovarian tumors and their significance to prognosis of ovarian cancer. PATIENTS AND METHODS: A total of 139 women with epithelial ovarian tumors were included: 86 malignant, 17 borderline and 36 benign. Density, percentage, mean size and number of blood microvessels in tumors were measured by immunohistochemistry with antibodies against CD34 and CD105. Lymphatic vessel density was assayed using the D2-40 antibody against podoplanin. RESULTS: Angiogenesis was most profuse in malignant tumors. Small size of lymph vessels predicted 26% shorter 5-year survival of ovarian cancer patients. Further, high percentage of lymphatic vessels in tumors was associated with lymph node metastasis, and high density with cancer recurrence. Lower number of microvessels, as assessed by CD34 staining, predicted shorter progression-free survival. Additionally, the large size of microvessels assessed by CD34 and the high number of vessels assessed by CD105 were related to residual tumor >1 cm at primary surgery and also, large vessel size was associated with stage III, as assessed by CD105 staining. CONCLUSION: CD34 and CD105 define different characteristics of microvessels. Parameters of lymph vessels may predict the prognosis of ovarian cancer.

Prognostic value of preoperative dynamic contrast-enhanced magnetic resonance imaging in epithelial ovarian cancer.

OBJECTIVES: To investigate whether semi-quantitative and pharmacokinetic perfusion dynamic contrast-enhanced (DCE) parameters are associated with traditional prognostic factors and can predict clinical outcome in ovarian cancer (OC). METHODS: This prospective study, approved by local ethical committee, enrolled 38 patients with primary OC, 2011-2014. After preoperative DCE-MRI (3.0 T), two observers measured perfusion (Ktrans, Kep, Ve, Vp) and semi-quantitative parameters (area under the curve, peak, time-to-peak) by drawing regions of interest (ROIs) covering the large solid lesion (L-ROI) and the most enhancing small area (S-ROI) (NordicICE platform). Kruskal-Wallis was used to analyze associations between MRI parameters and classified prognostic factors. RESULTS: Mean Ktrans values were higher in high-grade serous OC than in other types (L-ROI, P = 0.041; S-ROI, P = 0.018), and lower mean Ktrans values predicted residual tumor (L-ROI P = 0.030; S-ROI, P = 0.012). Higher minimum Vp values were associated with higher International Federation of Gynecology and Obstetrics (FIGO) stage (S-ROI, P = 0.023).Shorter recurrence-free survival was predicted by higher Ve (minimum L-ROI, P = 0.035; maximum S-ROI, P = 0.046), Vp (maximum S-ROI, P = 0.033), and lower time-to-peak (maximum S-ROI, P = 0.047) in Kaplan-Meier analysis. Multiparametric MRI variables combining DCE and diffusion weighted data were also predictive for survival. CONCLUSION: DCE-MRI parameters may represent imaging biomarkers for predicting tumor aggressiveness and prognosis in OC. Higher Ktrans levels were associated with better results in cytoreductive surgery but with earlier recurrence.

Dynamic contrast-enhanced perfusion parameters in ovarian cancer: Good accuracy in identifying high HIF-1α expression.

BACKGROUND: Hypoxia significantly influences treatment response and clinical outcome in solid tumors. A noninvasive marker for hypoxia will help physicians in treatment planning and encourage the efficient use of hypoxia targeted therapies. The purpose of this study was to investigate whether pharmacokinetic dynamic contrast-enhanced (DCE) perfusion parameters are associated with a specific marker of hypoxia, hypoxia-inducible factor 1 alpha (HIF-1α) in ovarian cancer (OC). MATERIALS AND METHODS: Thirty-eight patients with primary OC were enrolled in this prospective study approved by the local ethical committee. Patients underwent dynamic gadolinium-enhanced 3.0 T MRI as part of their staging investigations. Pharmacokinetic perfusion parameters, including a rate constant for transfer of contrast agent from plasma to extravascular extracellular space (EES) (Ktrans) and a rate constant from EES to plasma (Kep), were measured by drawing two types of regions of interest (ROIs): a large solid lesion (L-ROI) and a solid, most enhancing small area (S-ROI) (NordicICE platform). Tissue samples for immunohistochemical analysis were collected during surgery. Kruskal-Wallis, Mann-Whitney U and Chi-square tests were used in statistical analyses. Receiver Operating Characteristic curve analyzes were done for DCE parameters to discriminate high HIF-1α expression. RESULTS: Pharmacokinetic perfusion parameters Ktrans and Kep were inversely associated with HIF-1α expression (Ktrans L-ROI P = 0.021; Ktrans S-ROI P = 0.018 and Kep L-ROI P = 0.032; Kep S-ROI P = 0.033). Ktrans and Kep showed good accuracy in identifying high HIF-1α expression (AUC = 0.832 Ktrans L-ROI; 0.840 Ktrans S-ROI; 0.808 Kep L-ROI and 0.808 Kep L-ROI). CONCLUSION: This preliminary study demonstrated that pharmacokinetic DCE-MRI perfusion parameters are associated with the hypoxia specific marker, HIF-1α in OC. DCE-MRI may be a useful supplementary tool in the characterization of OC tumors in a staging investigation.

Preclinical safety, toxicology, and biodistribution study of adenoviral gene therapy with sVEGFR-2 and sVEGFR-3 combined with chemotherapy for ovarian cancer.

Abstract Antiangiogenic and antilymphangiogenic gene therapy with soluble vascular endothelial growth factor receptor-2 (VEGFR-2) and soluble VEGFR-3 in combination with chemotherapy is a potential new treatment for ovarian carcinoma. We evaluated the safety, toxicology, and biodistribution of intravenous AdsVEGFR-2 and AdsVEGFR-3 combined with chemotherapy in healthy rats (n=90) before entering a clinical setting. The study groups were: AdLacZ and AdLacZ with chemotherapy as control groups, low dose AdsVEGFR-2 and AdsVEGFR-3, high dose AdsVEGFR-2 and AdsVEGFR-3, combination of low dose AdsVEGFR-2 and AdsVEGFR-3 with chemotherapy, combination of high dose AdsVEGFR-2 and AdVEGFR-3 with chemotherapy, and chemotherapy only. The follow-up time was 4 weeks. Safety and toxicology were assessed by monitoring the clinical status of the animals and by histological, hematological, and clinical chemistry parameters. For the biodistribution studies, quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA) were used. Low dose (2×10(10) vp) AdsVEGFR-2 and AdsVEGFR-3 gene therapy was well tolerated, even when gene therapy was combined with chemotherapy. Notably, only transient elevation of liver enzymes and mild regenerative changes were seen in liver after the gene transfer in the groups that received high doses (2×10(11) vp) of AdsVEGFR-2 and AdsVEGFR-3 with or without chemotherapy. No life-threatening adverse effects were noticed in any of the treatment groups. The highest protein concentration of soluble VEGFR-2 (sVEGFR-2) in circulation was seen 1 week after the gene transfer. The combination of chemotherapy to gene therapy seemed to prolong the time of detectable transgene protein at least 1 week in the circulation. The expression of AdsVEGFR-2 and AdsVEGFR-3 transgenes was mainly seen in the liver and spleen as detected by qRT-PCR. According to these results, AdsVEGFR-2 and AdsVEGFR-3 gene therapy combined with chemotherapy is safe and can be brought to clinical testing in ovarian cancer patients.

In vivo SPECT/CT imaging of human orthotopic ovarian carcinoma xenografts with 111In-labeled monoclonal antibodies.

UNLABELLED: Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor 3 (VEGFR-3) are expressed in the tumor area during the progression of ovarian carcinoma. Monoclonal antibodies developed against these receptors are potential diagnostic molecules for in vivo imaging of ovarian carcinoma. METHODS: Biodistribution of the monoclonal antibodies cetuximab against EGFR and mF4-31C1 against VEGFR-3 was studied in nude mice with orthotopic SKOV-3m human ovarian carcinoma xenografts. The biodistribution of (111)Indium-labeled antibodies was followed up to 48 h postinjection using combined SPECT and CT imaging modality. Organ samples were collected postmortem and specific organ activity was measured. Accumulation of the intravenously injected antibodies in the tumor tissue and lymph nodes was verified using immunohistology. RESULTS: Imaging studies with SPECT/CT showed clear accumulation of both antibodies into tumor area. The tumor uptake was 8.78 ± 0.74 %ID/g for cetuximab and 5.77 ± 0.62 %ID/g for mF4-31C1 after 48 h postinjection. Cetuximab had lower liver tropism and faster tumor homing rate. In addition, after 48 h two of five tumor-bearing mice showed a clear accumulation of the In-labeled mF4-31C1 at the left axillary area. Both intravenously administered antibodies could also be detected from the tumor sections by immunohistological staining but only mF4-31C1 forms in the lymph nodes. CONCLUSION: These results demonstrate the accumulation of EGFR- and VEGFR-3-specific antibodies in orthotopic ovarian carcinoma tumors. Systemically administered they had slow pharmacokinetics which is typical for antibodies. Accumulation of mF4-31C1 antibody in the lymph nodes suggests the remote activation of VEGFR-3 by the primary tumor.

A highly reproducible xenograft model for human ovarian carcinoma and application of MRI and ultrasound in longitudinal follow-up.

OBJECTIVE: Typically, human ovarian cancer is widely disseminated at the time of diagnosis and shows extremely poor prognosis. Experimental animal models that mimic human ovarian cancer are often incomplete when compared to the full spectrum of the human disease with regard to its histological hallmarks such as the spread of carcinoma, its ability to seed the peritoneal cavity and formation of ascites. We have established and characterized a new animal model for human ovarian cancer in nude mouse. METHODS: A new cell line SKOV-3m was injected intraperitoneally in nude mice. Mice were divided in two groups A and B, which received 1 x 10(7) and 2 x 10(7) cells, respectively. Histology, immunohistochemistry, magnetic resonance imaging and ultrasound were used to analyze tumors. RESULTS: All mice had tumors within 18 days and histologically they resembled poorly differentiated human cystadenocarcinomas with bloody ascites. Mean survival of the mice was 42+/-14 and 21+/-2 days in groups A and B, respectively. Magnetic resonance imaging and ultrasound were used to confirm the presence of tumors and to monitor their growth without sacrificing the animals. CONCLUSION: This new xenograft model accompanied by noninvasive imaging is highly reproducible and likely to be very useful in testing new treatment strategies for ovarian cancer.