Clinical implications of angiogenesis in cancers

A Phase I Trial of Nab-Paclitaxel/Bevacizumab (AB160) Nano-Immunoconjugate Therapy for Gynecologic Malignancies

PURPOSE

AB160 is a 160-nm nano-immunoconjugate consisting of nab-paclitaxel (ABX) nanoparticles noncovalently coated with bevacizumab (BEV) for targeted delivery into tissues expressing high levels of VEGF. Preclinical data showed that AB160 resulted in greater tumor targeting and tumor inhibition compared with sequential treatment with ABX then BEV. Given individual drug activity, we investigated the safety and toxicity of AB160 in patients with gynecologic cancers.

PATIENTS AND METHODS

A 3+3 phase I trial was conducted with three potential dose levels in patients with previously treated endometrial, cervical, and platinum-resistant ovarian cancer to ascertain the recommended phase II dose (RP2D). AB160 was administered intravenously on days 1, 8, and 15 of a 28-day cycle (ABX 75-175 mg/m2, BEV 30-70 mg/m2). Pharmacokinetic analyses were performed.

RESULTS

No dose-limiting toxicities (DLT) were seen among the three dose levels tested. Grade 3/4 toxicities included neutropenia, thromboembolic events, and leukopenia. DL2 (ABX 150 mg/m2, BEV 60 mg/m2) was chosen as the RP2D. Seven of the 19 patients with measurable disease (36.8%) had confirmed partial responses (95% confidence interval, 16.3%-61.6%). Pharmacokinetic analyses demonstrated that AB160 allowed 50% higher paclitaxel dosing and that paclitaxel clearance mirrored that of therapeutic antibodies.

CONCLUSIONS

The safety profile and clinical activity of AB160 supports further clinical testing in patients with gynecologic cancers; the RP2D is DL2 (ABX 150 mg/m2, BEV 60 mg/m2).

Hypoxia-inducible factor in breast cancer: role and target for breast cancer treatment

Globally, breast cancer stands as the most prevalent form of cancer among women. The tumor microenvironment of breast cancer often exhibits hypoxia. Hypoxia-inducible factor 1-alpha, a transcription factor, is found to be overexpressed and activated in breast cancer, playing a pivotal role in the anoxic microenvironment by mediating a series of reactions. Hypoxia-inducible factor 1-alpha is involved in regulating downstream pathways and target genes, which are crucial in hypoxic conditions, including glycolysis, angiogenesis, and metastasis. These processes significantly contribute to breast cancer progression by managing cancer-related activities linked to tumor invasion, metastasis, immune evasion, and drug resistance, resulting in poor prognosis for patients. Consequently, there is a significant interest in Hypoxia-inducible factor 1-alpha as a potential target for cancer therapy. Presently, research on drugs targeting Hypoxia-inducible factor 1-alpha is predominantly in the preclinical phase, highlighting the need for an in-depth understanding of HIF-1α and its regulatory pathway. It is anticipated that the future will see the introduction of effective HIF-1α inhibitors into clinical trials, offering new hope for breast cancer patients. Therefore, this review focuses on the structure and function of HIF-1α, its role in advancing breast cancer, and strategies to combat HIF-1α-dependent drug resistance, underlining its therapeutic potential.

Assessing angiogenesis factors as prognostic biomarkers in breast cancer patients and their association with clinicopathological factors

INTRODUCTION

Angiogenesis is fundamental for tumor growth and metastasis across many solid malignancies. Considerable interest has focused on the molecular regulation of tumor angiogenesis as a means to predict disease outcomes and guide therapeutic decisions.

METHODS

In the present study, we investigated the prognostic value of transforming growth factor beta (TGF-β), epidermal growth factor (EGF), fibroblast growth factor (FGF), delta-like ligand 4 (DLL4), and vascular endothelial growth factor (VEGF) in the serum of 120 women diagnosed with breast cancer using ELISA as well as examined their associations with clinical parameters and the outcome of the disease.

RESULTS

Our results demonstrated that the serum concentration of TGF-β and EGF were remarkably higher in patients with higher tumor size, end stages of the disease, and positive lymph node involvement compared to patients with lower tumor size, early stages of the disease, and negative lymph node involvement. In addition, we found a significant correlation between the serum concentration of VEGF and the level of EGF, FGF, and DLL4 in patients with breast cancer. Furthermore, both univariate and multivariate analyses showed that TGF-β and EGF can be used as end-stage predictors.

DISCUSSION/CONCLUSION

Based on our findings, increasing the level of angiogenesis factors is significantly associated with higher tumor size and late stages of the disease in patients with breast cancer. Moreover, measuring the level of angiogenesis factors could lead to better prediction of disease outcomes and choosing the best treatments for patients.

Targeting of the NOX1/ADAM17 Enzymatic Complex Regulates Soluble MCAM-Dependent Pro-Tumorigenic Activity in Colorectal Cancer

The melanoma cell adhesion molecule, shed from endothelial and cancer cells, is a soluble growth factor that induces tumor angiogenesis and growth. However, the molecular mechanism accounting for its generation in a tumor context is still unclear. To investigate this mechanism, we performed in vitro experiments with endothelial/cancer cells, gene expression analyses on datasets from human colorectal tumor samples, and applied pharmacological methods in vitro/in vivo with mouse and human colorectal cancer cells. We found that soluble MCAM generation is governed by ADAM17 proteolytic activity and NOX1-regulating ADAM17 expression. The treatment of colorectal tumor-bearing mice with pharmacologic NOX1 inhibitors or tumor growth in NOX1-deficient mice reduced the blood concentration of soluble MCAM and abrogated the anti-tumor effects of anti-soluble MCAM antibodies while ADAM17 pharmacologic inhibitors reduced tumor growth and angiogenesis in vivo. Especially, the expression of MCAM, NOX1, and ADAM17 was more prominent in the angiogenic, colorectal cancer-consensus molecular subtype 4 where high MCAM expression correlated with angiogenic and lymphangiogenic markers. Finally, we demonstrated that soluble MCAM also acts as a lymphangiogenic factor in vitro. These results identify a role for NOX1/ADAM17 in soluble MCAM generation, with potential clinical therapeutic relevance to the aggressive, angiogenic CMS4 colorectal cancer subtype.

Advanced Techniques in Head and Neck Cancer Imaging: Guide to Precision Cancer Management

Precision treatment requires precision imaging. With the advent of various advanced techniques in head and neck cancer treatment, imaging has become an integral part of the multidisciplinary approach to head and neck cancer care from diagnosis to staging and also plays a vital role in response evaluation in various tumors. Conventional anatomic imaging (CT scan, MRI, ultrasound) remains basic and focuses on defining the anatomical extent of the disease and its spread. Accurate assessment of the biological behavior of tumors, including tumor cellularity, growth, and response evaluation, is evolving with recent advances in molecular, functional, and hybrid/multiplex imaging. Integration of these various advanced diagnostic imaging and nonimaging methods aids understanding of cancer pathophysiology and provides a more comprehensive evaluation in this era of precision treatment. Here we discuss the current status of various advanced imaging techniques and their applications in head and neck cancer imaging.

Novel Radiomic Measurements of Tumor-Associated Vasculature Morphology on Clinical Imaging as a Biomarker of Treatment Response in Multiple Cancers

PURPOSE

The tumor-associated vasculature (TAV) differs from healthy blood vessels by its convolutedness, leakiness, and chaotic architecture, and these attributes facilitate the creation of a treatment-resistant tumor microenvironment. Measurable differences in these attributes might also help stratify patients by likely benefit of systemic therapy (e.g., chemotherapy). In this work, we present a new category of computational image-based biomarkers called quantitative tumor-associated vasculature (QuanTAV) features, and demonstrate their ability to predict response and survival across multiple cancer types, imaging modalities, and treatment regimens involving chemotherapy.

EXPERIMENTAL DESIGN

We isolated tumor vasculature and extracted mathematical measurements of twistedness and organization from routine pretreatment radiology (CT or contrast-enhanced MRI) of a total of 558 patients, who received one of four first-line chemotherapy-based therapeutic intervention strategies for breast (n = 371) or non-small cell lung cancer (NSCLC, n = 187).

RESULTS

Across four chemotherapy-based treatment strategies, classifiers of QuanTAV measurements significantly (P < 0.05) predicted response in held out testing cohorts alone (AUC = 0.63-0.71) and increased AUC by 0.06-0.12 when added to models of significant clinical variables alone. Similarly, we derived QuanTAV risk scores that were prognostic of recurrence-free survival in treatment cohorts who received surgery following chemotherapy for breast cancer [P = 0.0022; HR = 1.25; 95% confidence interval (CI), 1.08-1.44; concordance index (C-index) = 0.66] and chemoradiation for NSCLC (P = 0.039; HR = 1.28; 95% CI, 1.01-1.62; C-index = 0.66). From vessel-based risk scores, we further derived categorical QuanTAV high/low risk groups that were independently prognostic among all treatment groups, including patients with NSCLC who received chemotherapy only (P = 0.034; HR = 2.29; 95% CI, 1.07-4.94; C-index = 0.62). QuanTAV response and risk scores were independent of clinicopathologic risk factors and matched or exceeded models of clinical variables including posttreatment response.

CONCLUSIONS

Across these domains, we observed an association of vascular morphology on CT and MRI-as captured by metrics of vessel curvature, torsion, and organizational heterogeneity-and treatment outcome. Our findings suggest the potential of shape and structure of the TAV in developing prognostic and predictive biomarkers for multiple cancers and different treatment strategies.

Methionine aminopeptidase 2 as a potential target in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDA) is an aggressive metastatic cancer with a very low survival rate. This tumor is hypovascularized and characterized by severe hypoxic regions, yet these regions are not impeded by the oxidative stress in their microenvironment. PDA's high resilience raises the need to find new effective therapeutic targets. This study investigated the suitability of methionine aminopeptidase 2 (MetAp2), a metallopeptidase known to play an important role in tumor progression, as a new target for treating PDA. In our examination of patient-derived PDA tissues, we found that MetAp2 is highly expressed in metastatic regions compared with primary sites. At the cellular level, we found that the basal expression levels of MetAp2 in pancreatic cancer cells were higher than its levels in endothelial cells. Pancreatic cancer cells showed a significant suppression of proliferation in a dose-dependent manner upon exposure to TNP-470, a selective MetAp2 inhibitor. In addition, a significant reduction in glutathione (GSH) levels - known for its importance in alleviating oxidative stress - was detected in all treated cells, suggesting a possible anti-cancer activity mechanism that would be feasible for treating highly hypoxic PDA tumors. Furthermore, in an orthotopic pancreatic cancer murine model, systemic oral treatment with a MetAp2 inhibitor significantly reduced tumors' growth. Taken together, our findings indicate that MetAp2 enhances tumor sensitivity to hypoxia and may provide an effective target for treating hypoxic tumors with high expression levels of MetAp2.

The impact of intraoperative radiotherapy on breast cancer: focus on the levels of angiogenic factors

OBJECTIVE

Angiogenesis is one of the hallmarks of cancers that is involved in tumor progression. Angiogenic factors induce the formation of new blood vessels and tumor extension, and finally reduce the survival of patients. Intraoperative radiotherapy (IORT), in which radiation is delivered to the tumor bed can kill cells and change tumor microenvironment. Here, we compared the impact of IORT on the levels of angiogenic factors in the blood and surgical wound fluids (SWF) of the breast cancer patients.

PATIENTS AND METHODS

Three hundred sixty patients, who had undergone breast-conserving surgery between 2013 and 2018, were enrolled in IORT and non-IORT groups non-randomly. Blood and drained wound fluid (WF) samples were collected from the patients before and after surgery, followed by quantification of the amounts of TGF-β, EGF, FGF, VEGF, and DLL4 in the patients using ELISA.

RESULTS

Our results were indicative of significant differences between the pre-surgery and post-surgery serum levels of EGF, DLL4, and VEGF. Furthermore, ROC analyses showed that TGF-β and DLL4 can differentiate of the early-stage from late-stage of the disease. Interestingly, the rate of the death and recurrence was reduced in IORT group.

CONCLUSIONS

In summary, IORT is a safe and effective treatment that can affect angiogenic factors and improve the overall- and recurrence-free survival of breast cancer patients.

Association between VEGF Gene Polymorphism -634G>C and Risk of Colorectal Cancer

BACKGROUND: Genetic and environmental factors play an important role in the pathogenesis of colorectal cancer. Angiogenesis is a central process in carcinogenesis and is affected by vascular endothelial growth factor (VEGF). Several genetic variations, such as polymorphism, may alter VEGF expression and influence the risk of colorectal cancer. AIM: The objective of this study was to determine the association between VEGF gene polymorphism -634G>C and risk of colorectal cancer. METHODS: A cross-sectional study was conducted at Haji Adam Malik general hospital and its sister hospitals. Subjects were obtained by consecutive sampling. Inclusion criteria for case and control groups were patients with colorectal cancer and healthy subject, respectively, aged 18 years or older and willing to participate in the study. Exclusion criteria were patients with systemic comorbidities or malignancies in other organs. Each subject undergoes an interview, colonoscopy, biopsy, serum VEGF level measurement, and VEGF polymorphism -634G>C evaluation. RESULTS: Eighty subjects were enrolled and distributed into case and control groups. Males were dominant in both groups, with a mean age of older than 55 years. Most lesions were in the rectum and 45% of subjects had moderately differentiated cancer. The median serum VEGF level in the case group was higher than the control group (2,175.1 pg/mL vs. 253 pg/mL; p < 0.001). VEGF gene polymorphism -634G > C was associated with the risk of colorectal cancer (p = 0.048). GG and GC genotypes had 1.89 times higher risk of colorectal cancer compared to the CC genotype. GG genotype and G allele had the highest serum VEGF levels. CONCLUSION: There is an association between VEGF gene polymorphism -634G>C and risk of colorectal cancer in this study.

Ameliorative potential of manganese nanoparticles with low-level ionizing radiation against experimentally induced hepatocarcinogenesis

Nanotechnology is a rich field with infinite possibilities of drug designs for cancer treatment. We aimed to biosynthesize manganese nanoparticles (Mn NPs) using Lactobacillus helveticus to investigate its anticancer synergistic effect with low-dose gamma radiation on HCC-induced rats. Diethylnitrosamine (DEN) (20 mg/kg BW, 5 times a week for 6 weeks) induced HCC in rats. Rats received Mn NPs (5 mg/kg BW/day) by gastric gavage over 4 weeks concomitant with single dose of gamma radiation (γ-R) (0.25 Gy). Characterization, cytotoxicity, and anticancer activity of Mn NPs were evaluated. DEN-induced significant liver dysfunction (alanine transaminase activity ALT, total proteins, and albumin levels) associated with significant increase in lipid peroxidation levels with reduction in super oxide dismutase activity. Furthermore, DEN intoxication is sponsored for remarkable increase in levels of Alfa-fetoprotein, tumor necrosis factor α, vascular endothelial growth factor, and transforming growth factor beta with remarkable decrease in caspase 3 and cytochrome c. Treatment with Mn NPs (4.98-11.58 nm) and single dose gamma radiation evoked significant repair in ALT, total protein, and albumin accompanied with balanced oxidative status, diminished inflammatory biomarkers, angiogenic factor, and growth factor with restoration in apoptotic factors. Mn NPs revealed obvious in vitro cytotoxic activity against HepG2 cell line in a dose-dependent manner. Our findings were well appreciated with the histopathological study. In conclusion, a new approach of the single or combined use of Mn NPs with low-dose γ-radiation regimens as promising paradigm for HCC treatment is recommended.

Impact of Surgery on the Hemangiogenic Profile, Especially VEGF Levels, in Lung Cancer Patients

Introduction: Lung cancer was considered to be rare at the beginning of the 20th century, but it has now reached almost epidemic proportions. It is the leading cause of cancer deaths in developed countries and is also rising at alarming rates in developing countries. Introduction: Coronavirus disease 2019 (COVID-19) is an emerging viral infection without any approved treatment. Investigational therapies for COVID-19 may cause clinically important drug-drug interactions (DDIs). We aimed to study drug-drug interactions (DDIs) and their risk factors in hospitalised COVID-19 patients. Aim: The aim of our study is to establish an effect on serum levels of vascular endothelial growth factor (VEGF) after surgery in lung cancer patients. Methods:This was a prospective study. For the estimation of VEGF, 50 lung cancer patients were studied. Both preoperative and postoperative levels of VEGF were estimated for all subjects. Blood samples were obtained from all cases both preoperatively and postoperatively (four weeks after surgery). Blood samples of 100 age and sex matched healthy controls were collected from the Outpatient Departments of SKIMS to establish normal serum VEGF levels. Conclusion: Our findings show that serum VEGF levels are higher as the tumor stage progresses and tumor size increases, which explains the lower serum VEGF levels observed by us in the operable patient group.

The KDR (VEGFR-2) Genetic Polymorphism Q472H and c-KIT Polymorphism M541L Are Associated With More Aggressive Behaviour in Astrocytic Gliomas

BACKGROUND/AIM

Better diagnostic and prognostic markers are required for a more accurate diagnosis and an earlier detection of glioma progression and for suggesting better treatment strategies. This retrospective study aimed to identify actionable gene variants to define potential markers of clinical significance.

MATERIALS AND METHODS

56 glioblastomas (GBM) and 44 grade 2-3 astrocytomas were profiled with next generation sequencing (NGS) as part of routine diagnostic workup and bioinformatics analysis was used for the identification of variants. CD34 immunohistochemistry (IHC) was used to measure microvessel density (MVD) and Log-rank test to compare survival and progression in the presence or absence of these variants.

RESULTS

Bioinformatic analysis highlighted frequently occurring variants in genes involved in angiogenesis regulation (KDR, KIT, TP53 and PIK3CA), with the most common ones being KDR (rs1870377) and KIT (rs3822214). The KDR variant was associated with increased MVD and shorter survival in GBM. We did not observe any correlation between the KIT variant and MVD; however, there was an association with tumour grade.

CONCLUSION

This study highlights the role of single-nucleotide variants (SNVs) that may be considered non-pathogenic and suggests the prognostic significance for survival of KIT rs3822214 and KDR rs1870377 and potential importance in planning new treatment strategies for gliomas.

Deciphering the Long Non-Coding RNAs and MicroRNAs Coregulation Networks in Ovarian Cancer Development: An Overview

Non-coding RNAs are emergent elements from the genome, which do not encode for proteins but have relevant cellular functions impacting almost all the physiological processes occurring in eukaryotic cells. In particular, microRNAs and long non-coding RNAs (lncRNAs) are a new class of small RNAs transcribed from the genome, which modulate the expression of specific genes at transcriptional and posttranscriptional levels, thus adding a new regulatory layer in the flux of genetic information. In cancer cells, the miRNAs and lncRNAs interactions with its target genes and functional pathways are deregulated as a consequence of epigenetic and genetic alterations occurring during tumorigenesis. In this review, we summarize the actual knowledge on the interplay of lncRNAs with its cognate miRNAs and mRNAs pairs, which interact in coregulatory networks with a particular emphasis on the mechanisms underlying its oncogenic behavior in ovarian cancer. Specifically, we reviewed here the evidences unraveling the relevant roles of lncRNAs/miRNAs pairs in altered regulation of cell migration, angiogenesis, therapy resistance, and Warburg effect. Finally, we also discussed its potential clinical implications in ovarian cancer and related endocrine disease therapies.

The Health-Promoting Properties and Clinical Applications of Rice Bran Arabinoxylan Modified with Shiitake Mushroom Enzyme-A Narrative Review

Rice bran arabinoxylan compound (RBAC) is derived from defatted rice bran hydrolyzed with Lentinus edodes mycelial enzyme. It has been marketed as a functional food and a nutraceutical with health-promoting properties. Some research has demonstrated this rice bran derivative to be a potent immunomodulator, which also possesses anti-inflammatory, antioxidant, and anti-angiogenic properties. To date, research on RBAC has predominantly focused on its immunomodulatory action and application as a complementary therapy for cancer. Nonetheless, the clinical applications of RBAC can extend beyond cancer therapy. This article is a narrative review of the research on the potential benefits of RBAC for cancer and other health conditions based on the available literature. RBAC research has shown it to be useful as a complementary treatment for cancer and human immunodeficiency virus infection. It can positively modulate serum glucose, lipid and protein metabolism in diabetic patients. Additionally, RBAC has been shown to ameliorate irritable bowel syndrome and protect against liver injury caused by hepatitis or nonalcoholic fatty liver disease. It can potentially ease symptoms in chronic fatigue syndrome and prevent the common cold. RBAC is safe to consume and has no known side effects at the typical dosage of 2–3 g/day. Nevertheless, further research in both basic studies and human clinical trials are required to investigate the clinical applications, mechanisms, and effects of RBAC.

Targeting Intercellular Communication in the Bone Microenvironment to Prevent Disseminated Tumor Cell Escape from Dormancy and Bone Metastatic Tumor Growth

Metastasis to the bone is a common feature of many cancers including those of the breast, prostate, lung, thyroid and kidney. Once tumors metastasize to the bone, they are essentially incurable. Bone metastasis is a complex process involving not only intravasation of tumor cells from the primary tumor into circulation, but extravasation from circulation into the bone where they meet an environment that is generally suppressive of their growth. The bone microenvironment can inhibit the growth of disseminated tumor cells (DTC) by inducing dormancy of the DTC directly and later on following formation of a micrometastatic tumour mass by inhibiting metastatic processes including angiogenesis, bone remodeling and immunosuppressive cell functions. In this review we will highlight some of the mechanisms mediating DTC dormancy and the complex relationships which occur between tumor cells and bone resident cells in the bone metastatic microenvironment. These inter-cellular interactions may be important targets to consider for development of novel effective therapies for the prevention or treatment of bone metastases.

CXCL3 Signaling in the Tumor Microenvironment

Cancer progression is driven, to a large extent, by the action of immune cells that have been recruited to tumor sites through interactions between chemokines and their receptors. Chemokines of the CXC subfamily are secreted by both tumor and non-tumor cells within the microenvironment of the tumor, where they induce either antitumor or protumor activity that fosters either clearance or progression of the tumor, respectively. Understanding the nature of these interactions is important to envisage novel approaches targeting the essential components of the tumor microenvironment, increasing the odds for favorable patient outcomes. In this chapter we describe the involvement of the chemokine (C-X-C motif) ligand 3 (CXCL3) in the human tumor microenvironment and its effects on immune and non-immune cells. Because of the limited data on the CXCL3 signaling in the tumor microenvironment, we extend the review to other members of the CXC subfamily of chemokines. This review also addresses the future trends or directions for therapeutic interventions that target signaling pathways used by these molecules in the tumor microenvironment.

VEGF Expression in Colorectal Cancer Metastatic Lymph Nodes: Clinicopathological Correlation and Prognostic Significance

Background: Angiogenesis plays an important role in colorectal cancer (CRC) tumorigenesis and metastatic progression. Methods: The present series consisted of CRC lymph node metastasis (LNM) tissue samples from 210 patients. Archival paraffin embedded LNM tissue were used to build up tissue microarray blocks and VEGF expression was immunohistochemically assessed. Results: VEGF-A and VEGF-C are overexpressed in LNM. VEGF-A was associated with patient age (p < 0.001), and VEGFR-2 and VEGFR-3 with CRC relapse (p = 0.032; p = 0.030, respectively). VEGF-C positivity was associated with VEGFR-3 positivity (p = 0.031), and VEGF-D with VEGFR-2 and VEGFR-3 (p ≤ 0.001). Matching the expression in LNM with CRC, in CRC VEGF-A positivity associates with VEGF-A, VEGF-C, VEGF-D, VEGF-R2, VEGF-R3 positivity in LNM; CRC VEGF-C with VEGF-D, VEGFR-2, VEGFR-3; CRC VEGFR-2 with VEGF-A, VEGF-C, VEGF-D, VEGFR-2, VEGFR-3; CRC VEGFR-3 with VEGF-A, VEGF-C, VEGF-D, VEGFR-2, VEGFR-3 in LNM. Conclusion: This study provides new information, revealing that VEGF family expression is increased in LNM. The association between the expression of VEGFR-2 and VEGFR-3 in LNM with CRC relapse reveals its impact on patient prognosis. Interesting data were found when the relationship between these proteins in primary tumor and their metastasis, were analyzed; VEGFA positivity in primary tumor is positively related to VEGF-A, VEGF-C, VEGF-D, VEGFR-2 and VEGFR-3 in their respective LNM suggesting mutual influence.

Perfusion-driven Intravoxel Incoherent Motion (IVIM) MRI in Oncology: Applications, Challenges, and Future Trends

Recent developments in MR hardware and software have allowed a surge of interest in intravoxel incoherent motion (IVIM) MRI in oncology. Beyond diffusion-weighted imaging (and the standard apparent diffusion coefficient mapping most commonly used clinically), IVIM provides information on tissue microcirculation without the need for contrast agents. In oncology, perfusion-driven IVIM MRI has already shown its potential for the differential diagnosis of malignant and benign tumors, as well as for detecting prognostic biomarkers and treatment monitoring. Current developments in IVIM data processing, and its use as a method of scanning patients who cannot receive contrast agents, are expected to increase further utilization. This paper reviews the current applications, challenges, and future trends of perfusion-driven IVIM in oncology.

Iodine Parameters in Triple-Bolus Dual-Energy CT Correlate With Perfusion CT Biomarkers of Angiogenesis in Renal Cell Carcinoma

OBJECTIVE. The purpose of this study is to determine the degree of the relationship between perfusion CT (PCT) parameters and iodine concentration metrics derived from triple-bolus dual-energy CT (DECT) and to compare the radiation dose delivered. SUBJECTS AND METHODS. This single-center prospective study was conducted from October 2015 to September 2017. Twenty-three consenting adults (15 men and eight women; mean [± SD] age, 56 ± 13 years [range, 25-78 years]) with renal cell carcinomas underwent consecutive PCT and triple-bolus DECT examinations. Triple-bolus DECT consisted of synchronous corticomedullary, nephrographic, and delayed phase scans acquired using a dual-source DECT scanner. Two readers independently analyzed blood flow, blood volume, and permeability, as measured by PCT, and iodine density and iodine ratio, as measured by triple-bolus DECT. Size-specific dose estimates were calculated for both groups. RESULTS. Interreader agreement was good for permeability (intraclass correlation coefficient [ICC] =.812) and blood flow (ICC = 0.849) and excellent for blood volume (ICC = 0.956), iodine density (ICC = 0.961), and iodine ratio (ICC = 0.956). Very strong positive correlations were found between blood volume and iodine density (p < 0.001) and between blood volume and iodine ratio (p < 0.001). Strong positive correlations were found between blood flow and iodine density (p < 0.001) and between blood flow and iodine ratio (p < 0.001). The correlations between permeability and iodine density (p = 0.01) and between permeability and iodine ratio (p = 0.02) were moderate. The mean size-specific dose estimate of triple-bolus DECT was approximately 15 times lower than that of PCT (p < 0.001). CONCLUSION. Quantitative iodine metrics derived from triple-bolus DECT showed significant correlation with CT parameters in renal cell carcinoma, with a significantly lower radiation dose.

Changes in the Expression Profile of VEGF-A, VEGF-B, VEGFR-1, VEGFR-2 in Different Grades of Endometrial Cancer

Background

VEGF-A, VEGF-B, VEGFR-1 and VEGFR-2 are important proteins involved in the induction and development of a new blood vessel network through which the tumor is properly nourished and oxygenated.

Objectives

The aim of the study was to evaluate changes in VEGF-A, VEGF-B, VEGFR-1 and VEGFR-2 expression in endometrial cancer depending on its grade and to determine the VEGFR-1 to VEGFR-2 concentration ratio.

Methods

The study group consisted of 45 patients diagnosed with endometrial cancer (G1, 17; G2, 15; G3, 13). The control group included 15 patients. VEGF-A, VEGF-B, VEGF-R1, VEGFR-2 expression was assessed using the immunohistochemical method. Statistical analysis was carried out using the Statistica 12 PL program (StatSoft, Cracow, Poland). It included the one-way ANOVA and Tukey's post-hoc test (p<0.05).

Results

Statistically significant differences in the level of VEGF-A, VEGF-B, VEGF-R1, VEGFR-2 were observed between the majority of analyzed groups (except for VEGF-B; G3 vs. G1, p=0.997700). The expression pattern of VEGF-A, VEGF-R1, VEGFR-2 was as follows: G3>G2>G1>C; VEGF-B: G2> G3> G1>C. A lower concentration of VEGFR-1 than VEGFR-2 was found regardless of the cancer grade.

Conclusion

VEGF-A, VEGF-B, VEGF-R1, VEGFR-2 are key proteins involved in tumor angiogenesis. The analysis of the entire panel of proteins participating in a given process is an important element of modern diagnostics. The concentration ratio of VEGFR-1 to VEGFR-2 appears to be a determining factor in the patients' survival prognosis.

5-fluorouracil and other fluoropyrimidines in colorectal cancer: Past, present and future

5-Fluorouracil (5-FU) is an essential component of systemic chemotherapy for colorectal cancer (CRC) in the palliative and adjuvant settings. Over the past four decades, several modulation strategies including the implementation of 5-FU-based combination regimens and 5-FU pro-drugs have been developed and tested to increase the anti-tumor activity of 5-FU and to overcome the clinical resistance. Despite the encouraging progress in CRC therapy to date, the patients' response rates to therapy continue to remain low and the patients' benefit from 5-FU-based therapy is frequently compromised by the development of chemoresistance. Inter-individual differences in the treatment response in CRC patients may originate in the unique genetic and epigenetic make-up of each individual. The critical element in the current trend of personalized medicine is the proper comprehension of causes and mechanisms contributing to the low or lack of sensitivity of tumor tissue to 5-FU-based therapy. The identification and validation of predictive biomarkers for existing 5-FU-based and new targeted therapies for CRC treatment will likely improve patients' outcomes in the future. Herein we present a comprehensive review summarizing options of CRC treatment and the mechanisms of 5-FU action at the molecular level, including both anabolic and catabolic ways. The main part of this review comprises the currently known molecular mechanisms underlying the chemoresistance in CRC patients. We also focus on various 5-FU pro-drugs developed to increase the amount of circulating 5-FU and to limit toxicity. Finally, we propose future directions of personalized CRC therapy according to the latest published evidence.

UPLC-MS Analysis of Cannabis sativa Using Tetrahydrocannabinol (THC), Cannabidiol (CBD), and Tetrahydrocannabinolic Acid (THCA) as Marker Compounds: Inhibition of Breast Cancer Cell Survival and Progression

Cannabis sativa L. extracts were characterized by ultra performance liquid chromatography-mass spectrometry (UPLC-MS) using tetrahydrocannabinol (THC), cannabidiol (CBD), and tetrahydrocannabinolic acid (THCA) as marker compounds. The inhibitory effects of various extracts were determined on the survival and progression of highly metastatic breast cancer cells. A higher amount of CBD was found in the dichloromethane extract, and this was found to be effective in inhibiting breast cancer cell growth in vitro and in angiogenesis. Collectively, it may be concluded that CBD, THC, and THCA in the African variety of C. sativa can be used as marker compounds in UPLC-MS analysis. The ability of the plant to inhibit breast cancer cell survival and progression may affirm the traditional use of the drug as an anticancer agent.

Sensitivity of Multiphase Pseudocontinuous Arterial Spin Labelling (MP pCASL) Magnetic Resonance Imaging for Measuring Brain and Tumour Blood Flow in Mice

Brain and tumour blood flow can be measured noninvasively using arterial spin labelling (ASL) magnetic resonance imaging (MRI), but reliable quantification in mouse models remains difficult. Pseudocontinuous ASL (pCASL) is recommended as the clinical standard for ASL and can be improved using multiphase labelling (MP pCASL). The aim of this study was to optimise and validate MP pCASL MRI for cerebral blood flow (CBF) measurement in mice and to assess its sensitivity to tumour perfusion. Following optimization of the MP pCASL sequence, CBF data were compared with gold-standard autoradiography, showing close agreement. Subsequently, MP pCASL data were acquired at weekly intervals in models of primary and secondary brain tumours, and tumour microvessel density was determined histologically. MP pCASL measurements in a secondary brain tumour model revealed a significant reduction in blood flow at day 35 after induction, despite a higher density of blood vessels. Tumour core regions also showed reduced blood flow compared with the tumour rim. Similarly, significant reductions in CBF were found in a model of glioma 28 days after tumour induction, together with an increased density of blood vessels. These findings indicate that MP pCASL MRI provides accurate and robust measurements of cerebral blood flow in naïve mice and is sensitive to changes in tumour perfusion.

Angiodrastic Chemokines in Colorectal Cancer: Clinicopathological Correlations

Aim

To study the expression of angiodrastic chemokines in colorectal tumors and correlate findings with clinicopathological parameters and survival.

Methods

The proangiogenic factor VEGF, the angiogenic chemokines CXCL8 and CXCL6, and the angiostatic chemokine CXCL4 were measured by ELISA in tumor and normal tissue of 35 stage II and III patients and correlated with the histopathology markers Ki67, p53, p21, bcl2, EGFR, and MLH1 and 5-year survival. The Wilcoxon and chi-square tests were used for statistical comparisons.

Results

There was a significant increase of CXCL6 (p = 0.005) and VEGF (p = 0.003) in cancerous tissue compared to normal. Patients with lower levels of CXCL8 and CXCL4 lived significantly longer. Patients with loss of EGFR expression had higher levels of CXCL8 while p21 loss was associated with higher levels of CXCL6. Chemokine levels were not correlated with TNM or Dukes classification. Strong expression of p53 was accompanied by decreased survival.

Conclusions

(1) The angiogenic factors CXCL6 and VEGF are increased in colorectal cancer tissue with no association with the clinical stage of the disease or survival. (2) However, increased levels of tissue CXCL8 and CXCL4 are associated with poor survival. (3) Strong expression of p53 is found in patients with poor survival.

Biochemical Evidence for the Antitumor Potential of Garcinia mangostana Linn. On Diethylnitrosamine-Induced Hepatic Carcinoma

Background

Garcinia mangostana is extensively used in most of the Indian herbal pharmaceuticals and nutraceuticals.

Objective

The objective of this study was to elucidate the underlying biochemical protective mechanism of G. Mangostana Linn. fruit extract (GME) in deterioration of diethylnitrosamine (DEN)-induced hepatic carcinoma (HCC) in rats.

Materials and Methods

The cancer was induced using DEN to the experimental rats and treated with GME (200, 400, and 600 mg/kg) to find its anticancer property. The cancer biomarkers such as alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), hepatic hydroxyl proline, total tissue protein, and tumor necrosis factor-alpha levels were measured using ELISA. The vascular endothelial growth factor expressions were also seen in liver tissues using immunohistochemistry.

Results

In addition, there was a significant increase in serum AFP, CEA, hepatic hydroxylproline, and total tissue protein levels in HCC group versus the negative control group. In contrast, the groups with HCC subjected to either high or low dose of GME elicited significant reduction of AFP, CEA, hepatic hydroxylproline, and increase in total protein in serum compared to the untreated HCC rats. Interestingly, treatment with GME elicited marked improvement in the liver histological feature and downregulation of tumor necrosis factor-alpha levels in HCC groups. GME extract may have chemopreventive benefits by reducing the tumor promoting growth factor levels in HCC-induced group.

Conclusion

To sum up, all findings on curative groups had proved clearly that the GME has anticarcinogenic effect on the development of liver cancer induced by DEN in rats.

SUMMARY

Garcinia mangostana Linn. (GME) may have chemopreventive property by reducing the tumor promoting growth factor and tumor necrosis factor-alpha levels in diethylnitrosamine (DEN)-induced hepatic cancerThe suppression in the levels of cancer biomarkers by GME due to the presence of anticancer phytoconstituentsThe histological studies proved the effective dose of GME against DEN-induced experimental hepatic cancer. Abbreviations used: TNF-α: Tumor necrosis factor-alpha, PBS: Phosphate buffered saline, ROS: Reactive oxygen species, DNA: Deoxyribonucleic acid, GSH: Glutathione, VEGF: Vascular endothelial growth factor.

Assessing tumor angiogenesis in colorectal cancer by quantitative contrast-enhanced endoscopic ultrasound and molecular and immunohistochemical analysis

Background and Objectives

Data on contrast-enhanced endoscopic ultrasound (CE-EUS) for colorectal cancer (CRC) evaluation are scarce. Therefore, we aimed to assess the vascular perfusion pattern in CRC by quantitative CE-EUS and compare it to immunohistochemical and genetic markers of angiogenesis.

Patients and Methods

We performed a retrospective analysis of CE-EUS examinations of 42 CRC patients, before any therapy. CE-EUS movies were processed using a dedicated software. Ten parameters were automatically generated from the time-intensity curve (TIC) analysis: peak enhancement (PE), rise time (RT), mean transit time, time to peak (TTP), wash-in area under the curve (WiAUC), wash-in rate (WiR), wash-in perfusion index (WiPI), wash-out AUC (WoAUC), and wash-in and wash-out AUC (WiWoAUC). The expression levels of the vascular endothelial growth factor receptor 1 (VEGFR1) and VEGFR2 genes were assessed from biopsy samples harvested during colonoscopy. Microvascular density and vascular area were calculated after CD31 and CD105 immunostaining.

Results

Forty-two CE-EUS video sequences were analyzed. We found positive correlations between the parameters PE, WiAUC, WiR, WiPI, WoAUC, WiWoAUC, and N staging (Spearman r = 0.437, r = 0.336, r = 0.462, r = 0.437, r = 0.358, and r = 0.378, respectively, P < 0.05), and also between RT and TTP and CD31 vascular area (r = 0.415, and r = 0.421, respectively, P < 0.05). VEGFR1 and VEGFR2 expression did not correlate with any of the TIC parameters.

Conclusions

CE-EUS with TIC analysis enables minimally invasive assessment of CRC angiogenesis and may provide information regarding the lymph nodes invasion. However, further studies are needed for defining its role in the evaluation of CRC patients.

Antiangiogenic mechanisms and factors in breast cancer treatment

Breast cancer is known to metastasize in its latter stages of existence. The different angiogenic mechanisms and factors that allow for its progression are reviewed in this article. Understanding these mechanisms and factors will allow researchers to design drugs to inhibit angiogenic behaviors and control the rate of tumor growth.

Angiogenesis in Breast Cancer and its Correlation with Estrogen, Progesterone Receptors and other Prognostic Factors

PURPOSE

The aim of study is to evaluate angiogenesis using CD34, in estrogen, progesterone positive and negative breastcancer and to correlate the microvessel density with known histological prognostic factors, morphological type of breast carcinoma and lymph node metastasis.

MATERIALS AND METHODS

Twenty eight untreated cases of breast cancer were included in the study and paraffin embedded sections were obtained from representative mastectomy specimen of breast cancer patient. The sections were stained with hematoxylin and eosin stain and immunohistochemistry was performed using CD34, estrogen, progesterone, cytokeratin and epithelial membrane antigen antibody. Angiogenesis was analysed using CD 34 antibody. For statistical analysis, cases were grouped into estrogen, progesterone positive and negative receptors.

RESULTS

Mean microvessel density in ER-/PR-, ER-/ PR+, ER+/PR-, ER+/PR+ was 15.45, 14.83, 11, 10.89 respectively. A significant correlation was found between ER receptors and mean vascular density with p-value (< 0.05). A significant difference was observed in mean vascular density between the four groups comprising (p-value < 0.05). Infiltrating duct carcinoma (NOS) grade III has got the highest mean microvessel density (14.17) followed by grade II (12.93) and grade I (12.33).

CONCLUSION

Information about prognostic factors in breast cancer patients may lead to better ways to identify those patients at high risk who might benefit from adjuvant therapies.

What could Nintedanib (BIBF 1120), a triple inhibitor of VEGFR, PDGFR, and FGFR, add to the current treatment options for patients with metastatic colorectal cancer?

Increasing knowledge of the pro-angiogenic processes involved in the progression of metastatic colorectal cancer (mCRC) has resulted in the clinical development of several anti-angiogenic agents, with bevacizumab currently being the only approved agent for mCRC. Nintedanib (BIBF 1120) has been shown to block the vascular endothelial growth factor receptor (VEGFR), the platelet-derived growth factor receptor (PDGFR), and the fibroblast growth factor receptor (FGFR). By targeting FGFR signaling, nintedanib may overcome resistance to previous anti-VEGF treatments, and may represent a better approach in patients with high basal levels of circulating FGFs. In this article, the angiogenic mechanisms implicated in mCRC are reviewed (focusing on the signaling pathways activated by VEGFR, PDGFR, and FGFR), along with the clinical data for nintedanib in the context of other anti-angiogenic tyrosine kinase inhibitors under clinical development for mCRC. Biomarkers that could predict response to nintedanib are also discussed.

Molecular therapy of colorectal cancer: progress and future directions

Colorectal cancer (CRC) remains one of the most common types of cancer and leading causes of cancer death worldwide. Although the introduction of cytotoxic drugs such as oxaliplatin, irinotecan and fluorouracil has improved the treatment of advanced CRC, the individual response to chemoradiotherapy varies tremendously from one patient to another. However, recent progress in CRC molecular therapies may provide new insight into the treatment of this disease. Currently, components of the EGFR, VEGF, Wnt and NF-kB pathways are the most important targets for CRC therapy. This review chronicles the development of molecular CRC therapies over the past few decades. We also provide an update on the current progress of research concerning the molecular pathways leading to CRC and discuss the possible implications for CRC therapy.

miR-7641 modulates the expression of CXCL1 during endothelial differentiation derived from human embryonic stem cells

MicroRNAs (miRNAs) are a class of small noncoding RNAs that negatively regulate gene expression through binding to 3' untranslated region. We identified and characterized the novel miRNA, miR-7641, in human mesenchymal stem cells. The expression of miR-7641 was downregulated during differentiation from human embryonic stem cells to endothelial cells. The CXCL1, a member of the CXC chemokine family, is known as promoting neovascularization by binding G-protein coupled receptors and is related to endothelial cells biogenesis such as angiogenesis, and it was predicted as target gene of miR-7641 by computerized analysis and the luciferase reporter assay. The miR-7641 significantly suppressed CXCL1 of transcriptional and post-translational levels. These data suggest that miR-7641 might be related with differentiation of human endothelial cells.

Recombinant attenuated Salmonella typhimurium carrying a plasmid co-expressing ENDO-VEGI151 and survivin siRNA inhibits the growth of breast cancer in vivo

The aim of this study was to investigate the antitumor effect of a plasmid co-expressing ENDO-VEGI151 and survivin siRNA on breast cancer in nude mice, and to explore the feasibility of attenuated Salmonella typhimurium (S. typhimurium) as a delivery vector for cancer gene therapy in vivo. Three recombinant expression plasmids pENDO‑VEGI151 (pEV), pSurvivin-siRNA (psi-survivin) and co-expressing plasmid pENDO-VEGI151/survivin‑siRNA (pEV/si-survivin), were transferred into the attenuated S. typhimurium strain SL7207, respectively. MDA-MB-231 cells were infected with these recombinants in vitro, and the expression of ENDO-VEGI151 and survivin was detected. In order to detect S. typhimurium distribution and gene delivery efficiency in vivo, the plasmid pEGFP-N1 which encodes green fluorescent protein was transferred into SL7207, and the recombinant known as SL-pEGFP was orally administered to tumor-bearing nude mice. The gene transfer efficiency, distribution and survival time of the SL-pEGFP in vivo were evaluated by detection of GFP fluorescence. SL-pEGFP not only infected the cancer cells effectively, but also allowed the survival and expression of specific genes mainly in the xenografts of nude mice. To further identify the anticancer effects of these recombinants in vivo, mice burdened with xenografts were randomly divided into 6 groups, which were subjected to intragastric administration of vehicle, SL7207, SL-pcDNA3.1, SL-pEV, SL-psi-survivin and SL-pEV/si-survivin, respectively. Eight weeks after implantation, tumor size, weight, inhibition rate, intratumoral microvessel density (MVD), apoptotic index (AI), ENDO‑VEGI151 and survivin expression were evaluated. Compared with the SL-pEV or SL-psi-survivin-treated groups, the growth of tumors was significantly reduced in the SL-pEV/si-survivin group with an inhibition rate of 90.28 vs. 69.12 and 65.61%, respectively. MVD and the expression of survivin were decreased significantly in the SL-pEV/si-survivin-treated group, while AI increased significantly in the SL-pEV/si-survivin-treated group. These results indicated that attenuated S. typhimurium carrying the dual function plasmid pEV/si-survivin cannot only be specifically enriched in the tumor tissue, but also showed a synergistic antitumor effect in vivo.

Norcantharidin anti-angiogenesis activity possibly through an endothelial cell pathway in human colorectal cancer

The present study was based on the unexpected discovery that norcantharidin exerted anti-angiogenesis activity when effects on growth of human colon cancer were studied. The aim was to further verify this finding and explore possible mechanisms using a tumor xenograft model in nude mice. We confirmed that norcantharidin (5 or 15 mg/kg) could inhibit angiogenesis of human colon cancer in vivo. In vitro, crossing river assay, cell adhesion assay and tube formation assay indicated that NCTD could reduce the migration, adhesion and vascular network tube formation ability of HUVECs. At the same time, the expression levels of VEGF and VEGFR-2 proteins which play important roles in angiogenesis were reduced as examined by western blotting analysis. Taken together, the results firstly showed NCTD could inhibit angiogenesis of human colon cancer in vivo, probably associated with effects on migration, adhesion and vascular network tube formation of HUVECs and expression levels of VEGF and VEGFR-2 proteins.

Clinical significance of expression of caveolin-1 and vascular endothelial growth factor in colorectal carcinoma

AIM: To detect the expressions of caveolin-1 (Cav-1) and vascular endothelial growth factor (VEGF) in colorectal cancer and to analyze their correlation with the clinicopathological features of colorectal cancer.

METHODS: Immunohistochemistry was used to detect the expression of Cav-1 and VEGF in 83 colorectal carcinoma specimens and matched normal colorectal mucosal specimens.

RESULTS: The positive rate of Cav-1 expression was significantly lower in colorectal carcinoma than in normal colorectal mucosa (38.6% vs 81.9%, P < 0.01). VEGF was over-expressed in colorectal cancer compared to matched normal colorectal tissue (74.7% vs 13.3%, P < 0.01). The expression of Cav-1 and VEGF was significantly correlated with tumor differentiation, invasion depth and lymph node metastasis (all P < 0.05), but not with patient's age, sex or tumor size. There is a negative correlation between Cav-1 and VEGF expression in colorectal cancer (r = -0.393, P < 0.01).

CONCLUSION: The absent expression of Cav-1 and over-expression of VEGF may play an important role in the development and progression of colorectal carcinoma.

Peroxisome Proliferator-Activated Receptor-gamma Ligands: Potential Pharmacological Agents for Targeting the Angiogenesis Signaling Cascade in Cancer

Peroxisome proliferator-activated receptor-γ (PPAR-γ) has currently been considered as molecular target for the treatment of human metabolic disorders. Experimental data from in vitro cultures, animal models, and clinical trials have shown that PPAR-γ ligand activation regulates differentiation and induces cell growth arrest and apoptosis in a variety of cancer types. Tumor angiogenesis constitutes a multifaceted process implicated in complex downstream signaling pathways that triggers tumor growth, invasion, and metastasis. In this aspect, accumulating in vitro and in vivo studies have provided extensive evidence that PPAR-γ ligands can function as modulators of the angiogenic signaling cascade. In the current review, the crucial role of PPAR-γ ligands and the underlying mechanisms participating in tumor angiogenesis are summarized. Targeting PPAR-γ may prove to be a potential therapeutic strategy in combined treatments with conventional chemotherapy; however, special attention should be taken as there is also substantial evidence to support that PPAR-γ ligands can enhance angiogenic phenotype in tumoral cells.

Breast Tumor Angiogenesis and Tumor-Associated Macrophages: Histopathologist's Perspective

Much progress has been made since the conceptualization of tumor angiogenesis—the induction of growth of new blood vessels by tumor—as a salient feature of clinically significant primary or metastatic cancers. From a practicing histopathologist's point of view, we appraise the application of this concept in breast cancer with particular reference to the evaluation of proangiogenic factors and the assessment of new microvessels in histopathological examination. Recently, much focus has also been centered on the active roles played by tumor-associated macrophages in relation to tumor angiogenesis. We review the literature; many data supporting this facet of tumor angiogenesis were derived from the breast cancer models. We scrutinize the large body of clinical evidence exploring the link between the tumor-associated macrophages and breast tumor angiogenesis and discuss particularly the methodology and limitations of incorporating such an assessment in histopathological examination.

Role of endoglin and VEGF family expression in colorectal cancer prognosis and anti-angiogenic therapies

Colorectal cancer (CRC) is one of the cancer models and most of the carcinogenic steps are presently well understood. Therefore, successful preventive measures are currently used in medical practice. However, CRC is still an important public health problem as it is the third most common cancer and the fourth most frequent cause of cancer death worldwide. Nowadays, pathologic stage is a unique and well-recognized prognostic indicator, however, more accurate indicators of the biologic behavior of CRC are expected to improve the specificity of medical treatment. Angiogenesis plays an important role in the growth and progression of cancer but its role as a prognostic factor is still controversial. Probably the most important clinical implication of tumor angiogenesis is the development of anti-angiogenic therapy. The goal of this review is to critically evaluate the role of angiogenic markers, assessed by either endoglin-related microvessel density or expression of vascular endothelial growth factor family members in the CRC setting and discuss the role of these angiogenic markers in anti-angiogenic therapies.

In vitro imaging of angiogenesis using embryonic stem cell-derived endothelial cells

Angiogenesis is an important event during developmental processes, and it plays a key role in neovascularization. The development of an in vitro model that can be used for live imaging of vessel growth will facilitate the study of molecular and cellular mechanisms for the growth of blood vessels. Embryonic stem cells (ESCs) are considered to be a novel renewable source for the derivation of genetically manipulable endothelial cells (ECs). To derive green fluorescence protein (GFP)-expressing ECs, we used a transgenic ESC line in which a GFP reporter was driven by the endothelial-specific promoter fetal liver kinase 1. ESC-ECs were isolated from 11-day embryoid bodies by fluorescence-activated cell sorting. Embedding the aggregated ESC-ECs in a 3-dimensional collagen gel matrix resulted in ESC-EC migration out of the aggregates and coalescence into a capillary network. Time-lapse microscopy revealed EC migration, proliferation, lumen formation, and anastomosis to other capillary vessels during this process, which were reminiscent of angiogenic processes. Vascular endothelial growth factor plays major roles in the induction of ESC-EC angiogenesis in vitro. Blockage of the β1 integrin subunit severely impaired ESC-EC survival and migration. We demonstrate that our in vitro ESC-EC angiogenesis model represents a high-resolution dynamic video-image system for observing the cellular events underlying angiogenic cascades. We also consider this model as an image screening tool for the identification of pro-angiogenic and anti-angiogenic molecules.

Angiogenic targets for potential disorders

This review shall familiarize the readers with various fundamental aspects of angiogenesis. Angiogenesis is a feature of a limited number of physiological processes like wound healing, ovulation, development of the corpus luteum, embryogenesis, lactating breast, during immune response, and during Inflammation. It is driven by a cocktail of growth factors and pro-angiogenic cytokines and is tempered by an equally diverse group of inhibitors of neovascularization. The properties and biological functions of angiogenic growth factors such as VEGF, FGF-2, nitric oxide, MMP, angiopoietin, TGF-β as well as various inhibitors such as angiostatin, endostatin, thrombospondin, canstatin, DII4, PEDF are discussed in this review with respect to their impact on angiogenic process. In recent years, it has become increasingly evident that excessive, insufficient, or abnormal angiogenesis contributes to the pathogenesis of many more disorders. A long list of disorders is characterized or caused by excessive or insufficient angiogenesis whereas several congenital or inherited diseases are also caused by abnormal vascular remodeling. It may be possible in the future to develop specific anti-angiogenic agents that offer a potential therapy for cancer and angiogenic diseases.

Novel angiogenesis inhibitors: addressing the issue of redundancy in the angiogenic signaling pathway

Angiogenesis, the formation of new blood vessels from established vasculature, is a fundamental process in the growth and metastasis of solid tumours. It is a complex, tightly regulated process that requires the coordinated action of antiangiogenic and proangiogenic factors, the balance of which becomes disturbed during tumour development. Vascular endothelial growth factor (VEGF) and its receptor are the key mediators of angiogenesis and targets for multiple pharmacologic agents. Many patients treated with VEGF inhibitors survive for a longer period; however, eventual resistance is associated with progressive disease and death. Multiple approaches to overcome resistance have been investigated with varying success, including the use of agents that target multiple angiogenic factors or co-administration of angiogenesis inhibitors with standard chemotherapy or radiotherapy. It would appear that the future of angiogenic inhibitors lies in the intelligent combination of multiple targeted agents with other angiogenic inhibitors, as well as more conventional therapies to maximise therapeutic effect.

Human macrophage metalloelastase correlates with angiogenesis and prognosis of gastric carcinoma

BACKGROUND AND AIMS

The function of human macrophage metalloelastase (HME) also known as matrix metalloproteinase 12, in tumorigenesis is contradictory. The current study was designed to investigate the association of HME expression with angiogenesis and prognosis of gastric carcinomas.

METHODS

In situ hybridization and immunohistochemistry were used to detect HME in human gastric carcinomas, chronic gastritis with atypical hyperplasia, and normal gastric epithelium mucosa. The results were further confirmed by RT-PCR or semi-quantitative reverse transcription polymerase chain reaction and Western blotting in gastric carcinomas and paired noncancerous tissues. VEGF and microvessel density count were also detected by immunohistochemical staining in all carcinoma tissues. The prognostic significance of HME was assessed with multiple linear regression analysis and Cox proportional hazards model.

RESULTS

High expression of HME protein/mRNA was observed in gastric carcinomas and atypical hyperplasia tissues compared with normal gastric epithelium mucosa, or paired noncancerous tissues. HME protein/mRNA were negatively correlated with MVD (p < 0.01), VEGF (p < 0.01), tumor differentiation grade (p < 0.05), vascular invasion (p < 0.01), and recurrence (p < 0.05-0.01). HME protein was an independent influential factor of MVD (p < 0.01). HME protein/mRNA was an independent prognostic factor of gastric carcinoma (p < 0.05-0.01). Patients with overexpression of HME protein/mRNA demonstrated a significantly better survival rate compared with those who did not (p < 0.05-0.01).

CONCLUSIONS

Overexpression of HME is strongly correlated with the reduced angiogenesis and vascular invasion of gastric carcinoma, and may serve as a useful predictive indicator in patients with this disease.

Human macrophage metalloelastase correlates with angiogenesis and prognosis of gastric carcinoma

BACKGROUND AND AIMS

The function of human macrophage metalloelastase (HME) also known as matrix metalloproteinase 12, in tumorigenesis is contradictory. The current study was designed to investigate the association of HME expression with angiogenesis and prognosis of gastric carcinomas.

METHODS

In situ hybridization and immunohistochemistry were used to detect HME in human gastric carcinomas, chronic gastritis with atypical hyperplasia, and normal gastric epithelium mucosa. The results were further confirmed by RT-PCR or semi-quantitative reverse transcription polymerase chain reaction and Western blotting in gastric carcinomas and paired noncancerous tissues. VEGF and microvessel density count were also detected by immunohistochemical staining in all carcinoma tissues. The prognostic significance of HME was assessed with multiple linear regression analysis and Cox proportional hazards model.

RESULTS

High expression of HME protein/mRNA was observed in gastric carcinomas and atypical hyperplasia tissues compared with normal gastric epithelium mucosa, or paired noncancerous tissues. HME protein/mRNA were negatively correlated with MVD (p < 0.01), VEGF (p < 0.01), tumor differentiation grade (p < 0.05), vascular invasion (p < 0.01), and recurrence (p < 0.05-0.01). HME protein was an independent influential factor of MVD (p < 0.01). HME protein/mRNA was an independent prognostic factor of gastric carcinoma (p < 0.05-0.01). Patients with overexpression of HME protein/mRNA demonstrated a significantly better survival rate compared with those who did not (p < 0.05-0.01).

CONCLUSIONS

Overexpression of HME is strongly correlated with the reduced angiogenesis and vascular invasion of gastric carcinoma, and may serve as a useful predictive indicator in patients with this disease.

Expressão imunohistoquímica do marcador tumoral CD34 e P27 como fator prognóstico em adenocarcinoma de próstata clinicamente localizado após prostatectomia radical

OBJETIVO: Analisar a expressão imunoistoquímica do marcador CD34 e p27, como fator prognóstico em pacientes com neoplasia de próstata localizada. MÉTODOS: Análise de 100 casos de pacientes portadores de neoplasia prostática localizada submetida à cirurgia curativa. Realizou-se o preparo histológico habitual, seguido da reação imunoistoquímica para a detecção do acúmulo da proteína CD34 e p27 seguida de análise estatística. RESULTADOS: Na avaliação do marcador P27 e na correlação com as variáveis, observou-se diferença significativa no escore de Gleason com expressão positiva (P27 positivo) relacionada com PSA médio mais baixo (p=0,091), escore de Gleason mais baixo (p<0,0001) e menor área de tumor no CD34 (p=0,036). Correlacionando-se o marcador CD34 na área tumoral observou-se quanto menor o CD34 positivo menor é o valor do PSA (p<0,0001), e menor é o escore de Gleason (r=0,5726 ; p<0,0001) e quanto maior o CD34 positivo maior é o estadiamento (r=0,3305 ; p<0,0001) e a chance de recidiva (p=0,002). Os pacientes com estadiamento mais alto, também tinham maior área CD34 positivo (p<0,0001). CONCLUSÃO: Os marcadores P27 e CD34 estão associados com os eventos próprios ao câncer de próstata; contudo, apenas o CD34 foi capaz de determinar a possibilidade de recidiva bioquímica.

Effects of anti-VEGF treatment duration on tumor growth, tumor regrowth, and treatment efficacy

PURPOSE

Inhibition of the vascular endothelial growth factor (VEGF) axis is the basis of all currently approved antiangiogenic therapies. In preclinical models, anti-VEGF blocking antibodies have shown broad efficacy that is dependent on both tumor context and treatment duration. We aimed to characterize this activity and to evaluate the effects of discontinuation of treatment on the dynamics of tumor regrowth.

EXPERIMENTAL DESIGN

We evaluated the effects of anti-VEGF treatment on tumor growth and survival in 30 xenograft models and in genetic mouse models of cancer. Histologic analysis was used to evaluate the effects of treatment on tumor vasculature. We used a variety of treatment regimens to allow analysis of the effects of treatment duration and cessation on growth rate, survival, and vascular density.

RESULTS

Preclinical tumor models were characterized for their varied dependence on VEGF, thereby defining models for testing other agents that may complement or augment anti-VEGF therapy. We also found that longer exposure to anti-VEGF monoclonal antibodies delayed tumor growth and extended survival in established tumors from both cell transplants and genetic tumor models and prevented regrowth of a subset of residual tumors following cytoablative therapy. Discontinuation of anti-VEGF in established tumors resulted in regrowth at a rate slower than that in control-treated animals, with no evidence of accelerated tumor growth or rebound. However, more rapid regrowth was observed following discontinuation of certain chemotherapies. Concurrent administration of anti-VEGF seemed to normalize these accelerated growth rates.

CONCLUSIONS

In diverse preclinical models, continuous VEGF suppression provides maximal benefit as a single agent, combined with chemotherapy, or as maintenance therapy once chemotherapy has been stopped.