Expression of basic fibroblast growth factor correlates with resistance to paclitaxel in human patient tumors

Crosstalk between lipid metabolism and EMT: emerging mechanisms and cancer therapy

Lipids are the key component of all membranes composed of a variety of molecules that transduce intracellular signaling and provide energy to the cells in the absence of nutrients. Alteration in lipid metabolism is a major factor for cancer heterogeneity and a newly identified cancer hallmark. Reprogramming of lipid metabolism affects the diverse cancer phenotypes, especially epithelial-mesenchymal transition (EMT). EMT activation is considered to be an essential step for tumor metastasis, which exhibits a crucial role in the biological processes including development, wound healing, and stem cell maintenance, and has been widely reported to contribute pathologically to cancer progression. Altered lipid metabolism triggers EMT and activates multiple EMT-associated oncogenic pathways. Although the role of lipid metabolism-induced EMT in tumorigenesis is an attractive field of research, there are still significant gaps in understanding the underlying mechanisms and the precise contributions of this interplay. Further study is needed to clarify the specific molecular mechanisms driving the crosstalk between lipid metabolism and EMT, as well as to determine the potential therapeutic implications. The increased dependency of tumor cells on lipid metabolism represents a novel therapeutic target, and targeting altered lipid metabolism holds promise as a strategy to suppress EMT and ultimately inhibit metastasis.

FGF1 protects FGFR1-overexpressing cancer cells against drugs targeting tubulin polymerization by activating AKT via two independent mechanisms

Cancer drug resistance is a common, unpredictable phenomenon that develops in many types of tumors, resulting in the poor efficacy of current anticancer therapies. One of the most common, and yet the most complex causes of drug resistance is a mechanism related to dysregulation of tumor cell signaling. Abnormal signal transduction in a cancer cell is often stimulated by growth factors and their receptors, including fibroblast growth factors (FGFs) and FGF receptors (FGFRs). Here, we investigated the effect of FGF1 and FGFR1 activity on the action of drugs that disrupt tubulin polymerization (taltobulin, paclitaxel, vincristine) in FGFR1-positive cell lines, U2OS stably transfected with FGFR1 (U2OSR1) and DMS114 cells. We observed that U2OSR1 cells exhibited reduced sensitivity to the tubulin-targeting drugs, compared to U2OS cells expressing a negligible level of FGFRs. This effect was dependent on receptor activation, as inhibition of FGFR1 by a specific small-molecule inhibitor (PD173074) increased the cells’ sensitivity to these drugs. Expression of functional FGFR1 in U2OS cells resulted in increased AKT phosphorylation, with no change in total AKT level. U2OSR1 cells also exhibited an elevated MDR1 and blocking MDR1 activity with cyclosporin A increased the toxicity of paclitaxel and vincristine, but not taltobulin. Analysis of tubulin polymerization pattern using fluorescence microscopy revealed that FGF1 in U2OSR1 cells partially reverses the drug-altered phenotype in paclitaxel- and vincristine-treated cells, but not in taltobulin-treated cells. Furthermore, we showed that FGF1, through activation of FGFR1, reduces caspase 3/7 activity and PARP cleavage, preventing apoptosis induced by tubulin-targeting drugs. Next, using specific kinase inhibitors, we investigated which signaling pathways are responsible for the FGF1-mediated reduction of taltobulin cytotoxicity. We found that AKT kinase is a key factor in FGF1-induced cell protection against taltobulin in U2OSR1 and DMS114 cells. Interestingly, only direct inhibition of AKT or dual-inhibition of PI3K and mTOR abolished this effect for cells treated with taltobulin. This suggests that both canonical (PI3K-dependent) and alternative (PI3K-independent) AKT-activating pathways may regulate FGF1/FGFR1-driven cancer cell survival. Our findings may contribute to the development of more effective therapies and may facilitate the prevention of drug resistance in FGFR1-positive cancer cells.

NTD-DR: Nonnegative tensor decomposition for drug repositioning

Computational drug repositioning aims to identify potential applications of existing drugs for the treatment of diseases for which they were not designed. This approach can considerably accelerate the traditional drug discovery process by decreasing the required time and costs of drug development. Tensor decomposition enables us to integrate multiple drug- and disease-related data to boost the performance of prediction. In this study, a nonnegative tensor decomposition for drug repositioning, NTD-DR, is proposed. In order to capture the hidden information in drug-target, drug-disease, and target-disease networks, NTD-DR uses these pairwise associations to construct a three-dimensional tensor representing drug-target-disease triplet associations and integrates them with similarity information of drugs, targets, and disease to make a prediction. We compare NTD-DR with recent state-of-the-art methods in terms of the area under the receiver operating characteristic (ROC) curve (AUC) and the area under the precision and recall curve (AUPR) and find that our method outperforms competing methods. Moreover, case studies with five diseases also confirm the reliability of predictions made by NTD-DR. Our proposed method identifies more known associations among the top 50 predictions than other methods. In addition, novel associations identified by NTD-DR are validated by literature analyses.

A monoclonal antibody against basic fibroblast growth factor attenuates cisplatin resistance in lung cancer by suppressing the epithelial-mesenchymal transition

Objectives: To investigate the underlying mechanisms of how the basic fibroblast growth factor monoclonal antibody (bFGFmAb) attenuates cisplatin (DDP) resistance in lung cancer using A549 cells and cisplatin-resistant A549 cells (A549/DDP). Methods: Cancer cell proliferation, cell viability, and 50% inhibitory concentration (IC50) of cisplatin were assessed. Transwell assays were utilized to evaluate the invasion activity of tumor cells in response to treatment. Epithelial-to-mesenchymal transition markers and drug resistance proteins were analysed using Western blots. Results: We demonstrate that the bFGFmAb inhibits the proliferation and invasion of both A549 and A549/DDP cells. The bFGFmAb increases cisplatin sensitivity of both A549 and A549/DDP cells as evidenced by an increase in the IC50 of cisplatin in A549 and A549/DDP cells. Furthermore, bFGFmAb significantly increases the expression of E-cadherin, whilst decreasing the expression of N-cadherin and bFGF in both cell lines, thereby showing inhibition of epithelial-to-mesenchymal transition. In addition, we demonstrate that bFGFmAb significantly reduces the expression of the lung resistance protein. Conclusions: Our data suggests that the humanized bFGFmAb is a promising agent to attenuate cisplatin resistance in NSCLC. The underlying mechanism for this effect of bFGFmAb may be associated with the inhibition of epithelial-to-mesenchymal transition and reduced expression of lung resistance protein.

Predicting patient response with models trained on cell lines and patient-derived xenografts by nonlinear transfer learning

Preclinical models have been the workhorse of cancer research, producing massive amounts of drug response data. Unfortunately, translating response biomarkers derived from these datasets to human tumors has proven to be particularly challenging. To address this challenge, we developed TRANSACT, a computational framework that builds a consensus space to capture biological processes common to preclinical models and human tumors and exploits this space to construct drug response predictors that robustly transfer from preclinical models to human tumors. TRANSACT performs favorably compared to four competing approaches, including two deep learning approaches, on a set of 23 drug prediction challenges on The Cancer Genome Atlas and 226 metastatic tumors from the Hartwig Medical Foundation. We demonstrate that response predictions deliver a robust performance for a number of therapies of high clinical importance: platinum-based chemotherapies, gemcitabine, and paclitaxel. In contrast to other approaches, we demonstrate the interpretability of the TRANSACT predictors by correctly identifying known biomarkers of targeted therapies, and we propose potential mechanisms that mediate the resistance to two chemotherapeutic agents.

FGF/FGFR-Dependent Molecular Mechanisms Underlying Anti-Cancer Drug Resistance

Simple Summary

Deregulation of the FGF/FGFR axis is associated with many types of cancer and contributes to the development of chemoresistance, limiting the effectiveness of current treatment strategies. There are several mechanisms involved in this phenomenon, including cross-talks with other signaling pathways, avoidance of apoptosis, stimulation of angiogenesis, and initiation of EMT. Here, we provide an overview of current research and approaches focusing on targeting components of the FGFR/FGF signaling module to overcome drug resistance during anti-cancer therapy.

Abstract

Increased expression of both FGF proteins and their receptors observed in many cancers is often associated with the development of chemoresistance, limiting the effectiveness of currently used anti-cancer therapies. Malfunctioning of the FGF/FGFR axis in cancer cells generates a number of molecular mechanisms that may affect the sensitivity of tumors to the applied drugs. Of key importance is the deregulation of cell signaling, which can lead to increased cell proliferation, survival, and motility, and ultimately to malignancy. Signaling pathways activated by FGFRs inhibit apoptosis, reducing the cytotoxic effect of some anti-cancer drugs. FGFRs-dependent signaling may also initiate angiogenesis and EMT, which facilitates metastasis and also correlates with drug resistance. Therefore, treatment strategies based on FGF/FGFR inhibition (using receptor inhibitors, ligand traps, monoclonal antibodies, or microRNAs) appear to be extremely promising. However, this approach may lead to further development of resistance through acquisition of specific mutations, metabolism switching, and molecular cross-talks. This review brings together information on the mechanisms underlying the involvement of the FGF/FGFR axis in the generation of drug resistance in cancer and highlights the need for further research to overcome this serious problem with novel therapeutic strategies.

The Interplay between Oxidative Stress, Inflammation and Angiogenesis in Bladder Cancer Development

In 2018, 550,000 people were diagnosed with bladder cancer (BC), of which nearly 200,000 people died. Moreover, men are 4 times more likely than women to be diagnosed with BC. The risk factors include exposure to environmental and occupational chemicals, especially tobacco smoke, benzidine and genetic factors. Despite numerous studies, the molecular basis of BC development remains unclear. A growing body of evidence suggests that inflammation, oxidant-antioxidant imbalance and angiogenesis disorders may play a significant role in the development and progression of bladder cancer. The patients with bladder cancer were characterised by an increased level of reactive oxygen species (ROS), the products of lipid peroxidation, proinflammatory cytokines and proangiogenic factors as compared to controls. Furthermore, it was shown that polymorphisms localised in genes associated with these pathways may modulate the risk of BC. Interestingly, ROS overproduction may induce the production of proinflammatory cytokines, which finally activated angiogenesis. Moreover, the available literature shows that both inflammation and oxidative stress may lead to activation of angiogenesis and tumour progression in BC patients.

Endothelial Cells Promote Docetaxel Resistance of Prostate Cancer Cells by Inducing ERG Expression and Activating Akt/mTOR Signaling Pathway

Docetaxel is a first-line chemotherapy for the treatment of patients with castration-resistant prostate cancer (CRPC). Despite the good initial response of docetaxel, drug resistance will inevitably occur. Mechanisms underlying docetaxel resistance are not well elaborated. Endothelial cells (ECs) have been implicated in the progression and metastasis of prostate cancer. However, little attention has been paid to the role of endothelial cells in the development of docetaxel resistance in prostate cancer. Here, we sought to investigate the function and mechanism of endothelial cells involving in the docetaxel resistance of prostate cancer. We found that endothelial cells significantly promoted the proliferation of prostate cancer cells and decreased their sensitivity to docetaxel. Mechanistically, basic fibroblast growth factor (FGF2) secreted by endothelial cells leads to the upregulation of ETS related gene (ERG) expression and activation of the Akt/mTOR signaling pathway in prostate cancer cells to promote docetaxel resistance. In summary, these findings demonstrate a microenvironment-dependent mechanism mediating chemoresistance of prostate cancer and suggest that targeting FGF/FGFR signaling might represent a promising therapeutic strategy to overcome docetaxel resistance.

Ex Vivo Culture Models to Indicate Therapy Response in Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is characterized by a poor 5 year survival and varying response rates to both standard-of-care and new treatments. Despite advances in medicine and treatment methods, mortality rates have hardly decreased in recent decades. Reliable patient-derived tumor models offer the chance to predict therapy response in a personalized setting, thereby improving treatment efficacy by identifying the most appropriate treatment regimen for each patient. Furthermore, ex vivo tumor models enable testing of novel therapies before introduction in clinical practice. A literature search was performed to identify relevant literature describing three-dimensional ex vivo culture models of HNSCC to examine sensitivity to chemotherapy, radiotherapy, immunotherapy and targeted therapy. We provide a comprehensive overview of the currently used three-dimensional ex vivo culture models for HNSCC with their advantages and limitations, including culture success percentage and comparison to the original tumor. Furthermore, we evaluate the potential of these models to predict patient therapy response.

Intracellular partners of fibroblast growth factors 1 and 2 - implications for functions

Fibroblast growth factors 1 and 2 (FGF1 and FGF2) are mainly considered as ligands of surface receptors through which they regulate a broad spectrum of biological processes. They are secreted in non-canonical way and, unlike other growth factors, they are able to translocate from the endosome to the cell interior. These unique features, as well as the role of the intracellular pool of FGF1 and FGF2, are far from being fully understood. An increasing number of reports address this problem, focusing on the intracellular interactions of FGF1 and 2. Here, we summarize the current state of knowledge of the FGF1 and FGF2 binding partners inside the cell and the possible role of these interactions. The partner proteins are grouped according to their function, including proteins involved in secretion, cell signaling, nucleocytoplasmic transport, binding and processing of nucleic acids, ATP binding, and cytoskeleton assembly. An in-depth analysis of the network of these binding partners could indicate novel, non-classical functions of FGF1 and FGF2 and uncover an additional level of a fine control of the well-known FGF-regulated cellular processes.

FGF2-FGFR1 pathway activation together with thymidylate synthase upregulation is induced in pemetrexed-resistant lung cancer cells

Pemetrexed (MTA) is a folate antimetabolite used for treating non-small cell lung cancer. To elucidate the mechanisms of pemetrexed resistance in lung cancer, we established pemetrexed-resistant sublines in PC9 (mutant EGFR) and H1993 (wild-type EGFR) lung adenocarcinoma cell lines (PC9-MTA, H1993-MTA). Gene expression profile comparison by microarray analyses revealed enhanced fibroblast growth factor 2 (FGF2) and FGF receptor 1 (FGFR1) expression, confirmed by Western blotting, enzyme-linked immunosorbent assay, and reverse transcription-polymerase chain reaction. ERK phosphorylation was increased in PC9-MTA but decreased in H1993-MTA along with decreased downstream signaling molecule phosphorylation. Cellular morphological change from epithelial to spindle-shape together with increased mesenchymal marker protein expression was observed in H1993-MTA. SiRNA-mediated FGF2 knockdown partially restored pemetrexed sensitivity in both lines, whereas anti-FGFR1 inhibitor PD173074 restored pemetrexed sensitivity in PC9-MTA. FGF2 or FGFR1 inhibition decreased pERK levels in PC9-MTA but increased pEGFR levels together with downstream signaling molecule activation and reversed epithelial-mesenchymal transition marker protein expression in H1993-MTA. Although thymidylate synthase strongly facilitates the development of pemetrexed resistance, our results reveal involvement of the FGF2-FGFR1 pathway in pemetrexed resistance in lung cancer cells and suggest that cellular function alterations induced by FGF2-FGFR1 pathway activation depend on the innate feature of cancer cells.

BGJ398, A Pan-FGFR Inhibitor, Overcomes Paclitaxel Resistance in Urothelial Carcinoma with FGFR1 Overexpression

Paclitaxel (PTX) is commonly used to treat urothelial carcinoma (UC) after platinum-based chemotherapy has failed. However, single-agent taxane therapy is not sufficient to inhibit tumor progression and drug resistance in advanced UC. Epithelial-to-mesenchymal transition (EMT) induced by fibroblast growth factor receptor (FGFR)1 signaling has been proposed as a mechanism of PTX resistance, but it is unclear whether this can be overcome by FGFR1 inhibition. The present study investigated whether FGFR1 overexpression contributes to PTX resistance and whether FGFR inhibition can enhance PTX efficacy in UC. The effects of PTX combined with the FGFR inhibitor BGJ398 were evaluated in UC cell lines by flow cytometry; Western blot analysis; cell viability, migration, and colony forming assays; and RNA interference. PTX+BGJ398 induced cell cycle arrest and apoptosis in UC cells with mesenchymal characteristics was accompanied by downregulation of cyclin D1 protein and upregulation of gamma-histone 2A family member X and cleaved poly(ADP-ribose) polymerase. Additionally, PTX+BGJ398 synergistically suppressed UC cell migration and colony formation via regulation of EMT-associated factors, while FGFR1 knockdown enhanced the antitumor effect of PTX. These findings provide a basis for development of effective strategies for overcoming PTX resistance in UC through inhibition of FGFR1 signaling.

Astragalus Saponins and Liposome Constitute an Efficacious Adjuvant Formulation for Cancer Vaccines

Cancer vaccines mostly aim to induce cytotoxic T lymphocytes (CTLs) against tumors. An appropriate adjuvant is of fundamental importance for inducing cellular immune response. Since the antigen in particulate form is substantially more immunogenic than soluble form antigen, it is beneficial to interact with antigen-presenting cells membrane to induce robust CD8⁺ T cell activation following vaccination. Based on previous research, we designed an adjuvant formulation by combining Astragalus saponins, cholesterol, and liposome to incorporate antigen into a particulate delivery system, so as to enhance cellular immune response. Meanwhile, angiogenesis contributes to tumor growth and metastasis, and basic fibroblast growth factor (bFGF) is involved in tumor angiogenesis. Therefore, using lipo-saponins adjuvant formulation and a human recombinant bFGF antigen protein, we tried to induce bFGF-specific CTL response to inhibit tumor angiogenesis to achieve antitumor activity. After five immunizations, the lipo-saponins/bFGF complex elicited robust antibody response and markedly higher amount of interferon-γ in BALB/c mice, resulting in superior antitumor activities. Decreased microvessel density in CD31 immunohistochemistry and the lysis of vascular endothelial cells by the T lymphocytes from the immunized mice indicated that the immunity inhibited the angiogenesis of tumors and further led to the inhibition of tumors. Our data suggest that the approach to construct adjuvant formulation between liposome and Astragalus saponins appeared highly desirable, and that Astragalus saponins may be utilized as a valuable additive for enhancing the effectiveness of vaccines and stimulating an appropriate immune response that can benefit tumor therapy.

FGF1 induces resistance to chemotherapy in ovarian granulosa tumor cells through regulation of p53 mitochondrial localization

Ovarian cancer remains associated with a high mortality rate and relapse is too frequently seen after chemotherapeutic treatment of granulosa cell tumors (GCTs) or epithelial ovarian cancers (EOCs). It is thus of major importance to progress in the knowledge of the molecular mechanisms underlying chemoresistance of ovarian tumors. Overexpression of Fibroblast Growth Factor 1 (FGF1) is observed in various cancers, correlates with poor survival and could be responsible for resistance to platinum-based chemotherapy of serous ovarian cancers. How FGF1 promotes escape to chemotherapy remains unknown. In previous studies, we showed that FGF1 inhibits p53 transcriptional activities, leading to increased cell survival of neuronal or fibroblast cell lines. In this study, we show that FGF1 favors survival of COV434 cells upon treatment with etoposide and cisplatin, two common chemotherapeutic molecules used for ovarian cancer. Etoposide and cisplatin induced mitochondrial depolarization, cytochrome c release and caspase activation in COV434 cells. Overexpression of FGF1 counteracts these events and thus allows increased survival of ovarian cells. In this study, FGF1 had little effect on p53 stability and transcriptional activities. Etoposide induced p21 expression as expected, but p21 protein levels were even increased in the presence of FGF1. Using RNA interference, we showed that p21 exerts an anti-apoptotic activity in COV434 cells. However abrogating this activity was not sufficient to restore cell death of FGF1-overexpressing cells. We also show for the first time that p53 mitochondrial pathway is involved in the cell death of COV434 cells. Indeed, p53 accumulates at mitochondria upon etoposide treatment and inhibition of p53 mitochondrial localization using pifithrin-µ inhibits apoptosis of COV434 cells. FGF1 also decreases mitochondrial accumulation of p53 induced by etoposide. This constitutes a novel mechanism of action for FGF1 to promote cell survival in response to chemotherapy.

Vascular endothelial growth factor expression correlates with serum CA125 and represents a useful tool in prediction of refractoriness to platinum-based chemotherapy and ascites formation in epithelial ovarian cancer

There is an increasing need for the identification of novel biological markers and potential therapeutic targets in epithelial ovarian cancer (EOC). Given the critical role of growth factors in the biology of EOC, we aimed in the present study to evaluate the intratumoral expressions of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) proteins and their clinical relevance in a cohort of 100 patients with EOC. All patients received platinum-based chemotherapy after surgery. A comparative immunohistochemical study of normal ovarian and EOC tissues showed that both growth factors were expressed at higher levels in tumor samples. In our statistical analysis, while no association existed between the FGF expression status and the clinicopathological characteristics of patients, intratumoral VEGF was identified as a potential biomarker for the prediction of ascites formation. In addition, the expression status of VEGF appeared to independently predict overall survival and response to chemotherapy. Furthermore, a direct association was demonstrated between the pre-treatment VEGF expression and serum CA125 after three cycles of chemotherapy. In sum, we report for the first time to our knowledge the correlation between intratumoral VEGF and serum CA125 in EOC. Our data also shows the prognostic value of VEGF expression in EOC. These results suggest the potential value of intratumoral VEGF in patient stratification. Dual inhibition of VEGF and CA125 might bring about a better outcome for patients with EOC.

Role of angiogenesis in urothelial bladder carcinoma

Introduction

Bladder cancer is the most common urinary tract malignancy in western countries. In recent years, extensive research has suggested that angiogenesis plays an important role in bladder cancer biology, contributing to tumor growth and progression.

Material and methods

In this review, we discuss general mechanisms of angiogenesis and highlight the influence of pro- and anti-angiogenic factors, and cancer stem cells on bladder cancer biology, their relation to disease progression, and potential use in novel targeted therapies.

Results

Expression of a number of proangiogenic factors, including HIF-1, VEGF, bFGF, IL-8 and MMPs, as well as anti-angiogenic factor TSP-1, was found to be altered in bladder tumors. Involvement of cancer stem cells in bladder cancer development was also proposed.

Conclusions

High expression of most pro-angiogenic factors correlated with disease progression and shorter patient survival, but discrepancies between studies urge us to continue evaluating the significance of angiogenesis in bladder cancer.

miRNA-205 targets VEGFA and FGF2 and regulates resistance to chemotherapeutics in breast cancer

MicroRNAs (miRNAs) have critical roles in regulating cancer cell survival, proliferation and sensitivity to chemotherapy. The potential application of using miRNAs to predict chemotherapeutic response to cancer treatment is highly promising. However, the underlying mechanisms of chemotherapy response control by miRNAs remain to be fully identified and their prognostic value has not been fully evaluated. Here we show a strong correlation between miR-205 expression and chemosensitivtiy to TAC (docetaxol, doxorubicin plus cyclophosphamide), a widely-used neoadjuvant chemotherapy (NAC) regimen, for breast cancer patients. High level of miR-205 predicted better response to TAC regimen NAC in breast cancer patients. We found miR-205 downregulated in both MCF-7/A02 and CALDOX cells, two drug-resistant derivatives of MCF-7 and Cal51 cells, and its ectopic expression led to an increase in apoptosis resensitization of both drug-resistant cell lines to doxorubicin and taxol. We further show that miR-205 directly binds VEGFA and FGF2 mRNA 3′-UTRs and confirm that miR-205 levels are negatively correlated with VEGFA and FGF2 mRNA expression in breast cancer patients. Adding VEGFA and FGF2 exogenously to chemosensitive breast cancer cells and chemoresistant cells with miR-205 overexpression led to drug resistance. Consistently, low VEGFA and FGF2 expression correlated with better response to NAC in breast cancer patients. In addition, inhibition of tumor growth and resensitization to doxorubicin were also observed in mouse tumor xenografts from cells overexpressing miR-205. Taken together, our data suggest that miR-205 enhances chemosensitivity of breast cancer cells to TAC chemotherapy by suppressing both VEGFA and FGF2, leading to evasion of apoptosis. MiR-205 may serve as a predictive biomarker and a potential therapeutic target in breast cancer treatment.

The Development of an Angiogenic Protein "Signature" in Ovarian Cancer Ascites as a Tool for Biologic and Prognostic Profiling

Advanced ovarian cancer (AOC) is one of the leading lethal gynecological cancers in developed countries. Based on the important role of angiogenesis in ovarian cancer oncogenesis and expansion, we hypothesized that the development of an "angiogenic signature" might be helpful in prediction of prognosis and efficacy of anti-angiogenic therapies in this disease. Sixty-nine samples of ascitic fluid- 35 from platinum sensitive and 34 from platinum resistant patients managed with cytoreductive surgery and 1st-line carboplatin-based chemotherapy- were analyzed using the Proteome ProfilerTM Human Angiogenesis Array Kit, screening for the presence of 55 soluble angiogenesis-related factors. A protein profile based on the expression of a subset of 25 factors could accurately separate resistant from sensitive patients with a success rate of approximately 90%. The protein profile corresponding to the "sensitive" subset was associated with significantly longer PFS (8 [95% Confidence Interval {CI}: 8-9] vs. 20 months [95% CI: 15-28]; Hazard ratio {HR}: 8.3, p<0.001) and OS (20.5 months [95% CI: 13.5-30] vs. 74 months [95% CI: 36-not reached]; HR: 5.6 [95% CI: 2.8-11.2]; p<0.001). This prognostic performance was superior to that of stage, histology and residual disease after cytoreductive surgery and the levels of vascular endothelial growth factor (VEGF) in ascites. In conclusion, we developed an "angiogenic signature" for patients with AOC, which can be used, after appropriate validation, as a prognostic marker and a tool for selection for anti-angiogenic therapies.

Vasohibin-1 expression inhibits advancement of ovarian cancer producing various angiogenic factors

Vasohibin‐1 (VASH1) is a negative feedback regulator of angiogenesis, the first to be discovered, and was identified in vascular endothelial growth factor (VEGF)‐stimulated vascular endothelial cells. Vasohibin‐1 inhibits abnormal vascularization induced by various angiogenic factors including fibroblast growth factor and platelet‐derived growth factor (PDGF), in addition to VEGF. By focusing on this characteristic of VASH1, we investigated the antitumor effects of VASH1 expression on ovarian cancer cells that produce different angiogenic factors. By using a high VEGF‐producing ovarian cancer cell line, SHIN‐3, and a high PDGF‐producing ovarian cancer cell line, KOC‐2S, the cells were transfected with either a VEGF antagonist, soluble VEGF receptor‐1 (sVEGFR‐1, or sFlt‐1), or VASH1 genes to establish their respective cellular expression. The characteristics of these transfectants were compared with controls. We previously reported that the expression of sFlt‐1 inhibited tumor vascularization and growth of high VEGF‐producing ovarian cancer cells, reduced peritoneal dissemination and ascites development, and prolonged the survival time of the host. However, in the current study, the expression of sFlt‐1 had no such effect on the high PDGF‐producing ovarian cancer cells used here, whereas VASH1 expression inhibited tumor vascularization and growth, not only in high VEGF‐producing cells, but also in high PDGF‐producing cells, reduced their peritoneal dissemination and ascites, and prolonged the survival time of the host. These results suggest that VASH1 is an effective treatment for ovarian cancer cells that produce different angiogenic factors.

Fibroblast growth factors, old kids on the new block

The fibroblast growth factors (FGFs) are a family of cell intrinsic regulatory peptides that control a broad spectrum of cellular activities. The family includes canonic FGFs that elicit their activities by activating the FGF receptor (FGFR) tyrosine kinase and non-canonic members that elicit their activities intracellularly and via FGFR-independent mechanisms. The FGF signaling axis is highly complex due to the existence of multiple isoforms of both ligands and receptors, as well as cofactors that include the chemically heterogeneous heparan sulfate (HS) cofactors, and in the case of endocrine FGFs, the Klotho coreceptors. Resident FGF signaling controls embryonic development, maintains tissue homeostasis, promotes wound healing and tissue regeneration, and regulates functions of multiple organs. However, ectopic or aberrant FGF signaling is a culprit for various diseases, including congenital birth defects, metabolic disorder, and cancer. The molecular mechanisms by which the specificity of FGF signaling is achieved remain incompletely understood. Since its application as a druggable target has been gradually recognized by pharmaceutical companies and translational researchers, understanding the determinants of FGF signaling specificity has become even more important in order to get into the position to selectively suppress a particular pathway without affecting others to minimize side effects.

Epithelial-mesenchymal transition and drug resistance in breast cancer (Review)

Breast cancer is the leading cause of cancer death in women worldwide. Insensitivity of tumor cells to drug therapies is an essential reason arousing such high mortality. Epithelial-mesenchymal transition (EMT) is defined by the loss of epithelial characteristics and the acquisition of a mesenchymal phenotype. It is well known that EMT plays an important role in breast cancer progression. Recently, mounting evidence has demonstrated involvement of EMT in antagonizing chemotherapy in breast cancer. Here, we discuss the biological significance and clinical implications of these findings, with an emphasis on novel approaches that effectively target EMT to increase the efficacy of anticancer therapies.

Role of fibroblast growth factor in squamous cell carcinoma of the bladder: prognostic biomarker and potential therapeutic target

BACKGROUND

We evaluated the association of fibroblast growth factor (FGF2) expression with pathologic features and clinical outcomes of squamous cell carcinoma (SCC) of the urinary bladder.

METHODS

Immunohistochemistry of FGF2 was performed on radical cystectomy specimens with pure SCC from 1997 to 2003. The relationship between FGF2 and pathologic parameters and oncological outcome was assessed.

RESULTS

The study included 151 patients with SCC (98 men) with a median age of 52 years (range: 36-74 y). Schistosomal infection was found in 81% of patients. Pathologic category was T2 and T3 in 88% of patients and the grade was low in>50%. Lymph node invasion and lymphovascular invasion were found in 30.5% and 16%. Altered FGF2 was associated with tumor grade (P = 0.014), lymph node invasion, and lymphovascular invasion (P = 0.042). Altered FGF2 was associated with both disease recurrence and cancer-specific mortality (P≤0.001) in Kaplan-Meier analyses and was an independent predictor of cancer recurrence (hazard ratio = 2.561, P = 0. 009) and cancer-specific mortality (hazard ratio = 2.679, P = 0. 033) in multivariate Cox regression analyses. Adding FGF2 to a model including standard clinicopathologic prognostics (pathologic T category, lymph node status, and grade) showed a significant improvement (6%) in accuracy of prediction poor oncological outcome.

CONCLUSIONS

FGF2 overexpression is associated with aggressive pathologic features and worse outcomes after radical cystectomy for SCC, suggesting a good prognostic and possible therapeutic role.

Akt-activated endothelium constitutes the niche for residual disease and resistance to bevacizumab in ovarian cancer

Ovarian cancer is the second leading cause of cancer-related death in women worldwide. Despite optimal cytoreduction and adequate adjuvant therapies, initial tumor response is often followed by relapse suggesting the existence of a tumor niche. Targeted therapies have been evaluated in ovarian cancer to overcome resistant disease. Among them, antiangiogenic therapies inhibit new blood vessel growth, induce endothelial cell apoptosis, and block the incorporation of hematopoietic and endothelial progenitor cells into new blood vessels. Despite in vitro and in vivo successes, antivascular therapy with bevacizumab targeting VEGF-A has limited efficacy in ovarian cancer. The precise molecular mechanisms underlying clinical resistance to anti-VEGF therapies are not yet well understood. Among them, tumor and stromal heterogeneity might determine the treatment outcomes. The present study investigates whether abnormalities in the tumor endothelium may contribute to treatment resistance to bevacizumab and promote a residual microscopic disease. Here, we showed that ovarian cancer cells activate Akt phosphorylation in endothelial cells inducing resistance to bevacizumab leading to an autocrine loop based on FGF2 secretion. Altogether, our results point out the role of an activated endothelium in the resistance to bevacizumab and in the constitution of a niche for a residual disease.

Enrichment of breast cancer stem-like cells by growth on electrospun polycaprolactone-chitosan nanofiber scaffolds

A small population of highly tumorigenic breast cancer cells has recently been identified. These cells, known as breast-cancer stem-like cells (BCSC), express markers similar to mammary stem cells, and are highly resistant to chemotherapy. Currently, study of BCSC is hampered by the inability to propagate these cells in tissue culture without inducing differentiation. Recently, it was reported that proliferation and differentiation can be modified by culturing cells on electrospun nanofibers. Here, we sought to characterize the chemoresistance and stem-like properties of breast cancer cell lines grown on nanofiber scaffolds. Cells cultured on three-dimensional templates of electrospun poly(ε-caprolactone)-chitosan nanofibers showed increases in mammary stem cell markers and in sphere-forming ability compared with cells cultured on polystyrene culture dishes. There was no increase in proliferation of stem cell populations, indicating that culture on nanofibers may inhibit differentiation of BCSC. The increase in stemness was accompanied by increases in resistance to docetaxel and doxorubicin. These data indicate that BCSC populations are enriched in cells cultured on electrospun poly(ε-caprolactone)-chitosan nanofibers, scaffolds that may provide a useful system to study BCSC and their response to anticancer drug treatment.

Proteomic analysis of the proteins that are associated with the resistance to paclitaxel in human breast cancer cells

Cancers frequently develop resistance to paclitaxel but the underlying molecular mechanisms remain to be determined. We have investigated the proteins that are associated with the paclitaxel resistance in human breast cancer MCF-7 cells using proteomic analysis. Paclitaxel resistant human breast cancer MCF-7 cells (MCF-7/P) were established by escalating the concentrations of paclitaxel to drug-sensitive MCF-7 cells (MCF-7/S). The global protein profiles of MCF-7/P and MCF-7/S were compared using two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). Eleven proteins were upregulated while six proteins were downregulated in MCF-7/P cells. Western blot and real-time PCR analyses showed that the protein and mRNA levels of heterogeneous nuclear ribonucleoprotein (hnRNP C1/C2), SET nuclear oncogene (SET), aspartate aminotransferase (AAT), transgelin-2 (TAGLN2) were increased, while those of nucleoside-diphosphate kinase A (NDKA) were decreased in MCF-7/P cells. Accordingly, knockdown of TAGLN2 by siRNA sensitized MCF-7/P cells to paclitaxel and reduced the multidrug resistance (MDR). Our identification of differential proteins, particularly transgelin-2, provides new insights into the mechanism of MDR to paclitaxel and novel biological targets for breast cancer treatment.

Extracellular matrix metalloproteinase inducer (EMMPRIN) expression correlates positively with active angiogenesis and negatively with basic fibroblast growth factor expression in epithelial ovarian cancer

Purpose

The primary aim of this paper was to evaluate the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and its relationship with proangiogenic factors and microvessel density (MVD) in ovarian cancer.

Methods

The study group included 58 epithelial ovarian cancers (EOCs), 35 benign ovarian tumors, and 21 normal ovaries. The expression of EMMPRIN, vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) was assessed by ELISA of tissue homogenates. Antibodies against CD105, CD31, and CD34 were used to immunohistochemically assess MVD.

Results

We have found significantly higher EMMPRIN expression in EOC than in benign ovarian tumors and normal ovaries. Similarly, the VEGF expression was higher in EOC than in benign ovarian tumors and normal ovaries. By contrast, bFGF expression was lower in EOC than in benign ovarian tumors and ovary samples. EMMPRIN expression in EOC was directly correlated with VEGF expression and CD105-MVD, but inversely correlated with bFGF expression. Grade 2/3 ovarian cancers had increased expression of EMMPRIN and VEGF, increased CD105-MVD, and lowered expression of bFGF compared to grade 1 ovarian cancers. Moreover, EMMPRIN expression was higher in advanced (FIGO III and IV) ovarian cancer.

Conclusions

The upregulation of EMMPRIN and VEGF expression is correlated with increased CD105-MVD and silenced bFGF, which suggests early and/or reactivated angiogenesis in ovarian cancer. Aggressive EOC is characterized by the following: high expression of EMMPRIN and VEGF, high CD105-MVD, and low expression of bFGF.

P7 peptides targeting bFGF sensitize colorectal cancer cells to CPT-11

The low survival rate of patients with colorectal cancer (CRC) is mainly due to the drug resistance of tumor cells to chemotherapeutic agents. It has been reported that basic fibroblast growth factor (bFGF) is an essential factor involved in the epigenetic mechanisms of drug resistance, which provides a novel potential target for improving the sensitivity of tumor cells to chemotherapeutic agents. In this study, we first demonstrate that a novel bFGF antagonist, peptide P7, previously isolated by phage display technology, reversed bFGF-induced resistance to irinotecan hydrochloride (CPT-11), and counteracted the anti-apoptotic effects of bFGF on CPT-11-treated HT-29 cells. Further experiments indicated that the inhibition of Akt activation, the suppression of bFGF internalization, the increase in the Bax to Bcl-2 ratio and the downregulation of cytokeratin 8 (CK8) by P7 may contribute to the counteracting of the anti-apoptotic effects of bFGF, and further reversal of bFGF-induced resistance to CPT-11. Our results suggest that peptide P7 may have therapeutic potential in CRC as a sensitizer to chemotherapeutic agents by targeting bFGF.

Impact of anti-PLK1 siRNA-containing F3-targeted liposomes on the viability of both cancer and endothelial cells

We have previously described the development of novel sterically stabilized F3-targeted pH-sensitive liposomes, which exhibited the ability to target both cancer and endothelial cells. Herein, the therapeutic potential of those liposomes was assessed upon encapsulation of a siRNA against a well-validated molecular target, PLK1. Treatment of prostate cancer (PC3) and angiogenic endothelial (HMEC-1) cells with F3-targeted liposomes containing anti-PLK1 siRNA resulted in a significant decrease in cell viability, which was mediated by a marked PLK1 silencing, both at the mRNA and protein levels. Furthermore, pre-treatment of PC3 cells with F3-targeted liposomes containing anti-PLK1 siRNA enabled a 3-fold reduction of paclitaxel IC50 and a 2.5-fold augment of the percentage of cancer cells in G2/mitosis arrest, which ultimately culminated in cell death. Overall, the F3-targeted nanocarrier containing an anti-PLK1 siRNA might constitute a valuable system for prostate cancer treatment, either applied in a single schedule or combined with conventional chemotherapy.

Targeting fibroblast growth factor pathways in prostate cancer

Advanced prostate cancer carries a poor prognosis and novel therapies are needed. Research has focused on identifying mechanisms that promote angiogenesis and cellular proliferation during prostate cancer progression from the primary tumor to bone-the principal site of prostate cancer metastases. One candidate pathway is the fibroblast growth factor (FGF) axis. Aberrant expression of FGF ligands and FGF receptors leads to constitutive activation of multiple downstream pathways involved in prostate cancer progression including mitogen-activated protein kinase, phosphoinositide 3-kinase, and phospholipase Cγ. The involvement of FGF pathways in multiple mechanisms relevant to prostate tumorigenesis provides a rationale for the therapeutic blockade of this pathway, and two small-molecule tyrosine kinase inhibitors-dovitinib and nintedanib-are currently in phase II clinical development for advanced prostate cancer. Preliminary results from these trials suggest that FGF pathway inhibition represents a promising new strategy to treat castrate-resistant disease.

Fibroblast growth factor receptor inhibition synergizes with Paclitaxel and Doxorubicin in endometrial cancer cells

OBJECTIVE

The fibroblast growth factor (FGF) family of signaling molecules has been associated with chemoresistance and poor prognosis in a number of cancer types, including lung, breast, ovarian, prostate, and head and neck carcinomas. Given the identification of activating mutations in the FGF receptor 2 (FGFR2) receptor tyrosine kinase in a subset of endometrial tumors, agents with activity against FGFRs are currently being tested in clinical trials for recurrent and progressive endometrial cancer. Here, we evaluated the effect of FGFR inhibition on the in vitro efficacy of chemotherapy in endometrial cancer cell lines.

METHODS

Human endometrial cancer cell lines with wild-type or activating FGFR2 mutations were used to determine any synergism with concurrent use of the pan-FGFR inhibitor, PD173074, and the chemotherapeutics, doxorubicin and paclitaxel, on cell proliferation and apoptosis.

RESULTS

FGFR2 mutation status did not alter sensitivity to either chemotherapeutic agent alone. The combination of PD173074 with paclitaxel or doxorubicin showed synergistic activity in the 3 FGFR2 mutant cell lines evaluated. In addition, although nonmutant cell lines were resistant to FGFR inhibition alone, the addition of PD173074 potentiated the cytostatic effect of paclitaxel and doxorubicin in a subset of FGFR2 wild-type endometrial cancer cell lines.

CONCLUSIONS

Together these data suggest a potential therapeutic benefit to combining an FGFR inhibitor with standard chemotherapeutic agents in endometrial cancer therapy particularly in patients with FGFR2 mutation positive tumors.

Current status and implications of microRNAs in ovarian cancer diagnosis and therapy

Ovarian cancer is the fifth most common cancer among women and causes more deaths than any other type of female reproductive cancer. Currently, treatment of ovarian cancer is based on the combination of surgery and chemotherapy. While recurrent ovarian cancer responds to additional chemotherapy treatments, the progression-free interval becomes shorter after each cycle, as chemo-resistance increases until the disease becomes incurable. There is, therefore, a strong need for prognostic and predictive markers to help optimize and personalize treatment in order to improve the outcome of ovarian cancer. An increasing number of studies indicate an essential role for microRNAs in ovarian cancer progression and chemo-resistance. MicroRNAs (miRNAs) are small endogenous non-coding RNAs (~22bp) which are frequently dysregulated in cancer. Typically, miRNAs are involved in crucial biological processes, including development, differentiation, apoptosis and proliferation. Two families of miRNAs, miR-200 and let-7, are frequently dysregulated in ovarian cancer and have been associated with poor prognosis. Both have been implicated in the regulation of epithelial-to-mesenchymal transition, a cellular transition associated with tumor aggressiveness, tumor invasion and chemo-resistance. Moreover, miRNAs also have possible implications for improving cancer diagnosis; for example miR-200 family, let-7 family, miR-21 and miR-214 may be useful in diagnostic tests to help detect ovarian cancer at an early stage. Additionally, the use of multiple target O-modified antagomirs (MTG-AMO) to inhibit oncogenic miRNAs and miRNA replacement therapy for tumor suppressor miRNAs are essential tools for miRNA based cancer therapeutics. In this review we describe the current status of the role miRNAs play in ovarian cancer and focus on the possibilities of microRNA-based therapies and the use of microRNAs as diagnostic tools.

Molecular phenotyping of circulating tumour cells in patients with prostate cancer: prediction of distant metastases

What's known on the subject? and What does the study add? The role of circulating cancer cells in metastogenesis is generally accepted. Two forms of these cells have been reported in a number of studies, cancer cell clusters (CCCs) and individual epithelial cancer cells. Clusters appear at higher frequencies in the blood. CCCs have been reported to be rich in vimentin and poor in E-cadherin expression The resulting epithelial to mesenchymal transition, a prerequisite for metastasis formation, occurs in CCCs. We have developed a new set of biomarkers, namely the antioxidant genes GPX1, SOD2 and TXNRD1, specific to cell trafficking in the blood. Firstly, the study shows that diagnosis of distant metastases is feasible by applying molecular phenotyping with a five gene test that has 94% sensitivity and 81% accuracy. Again SOD2 and GPX1 showed the highest sensitivities. Secondly, the study shows the efficacy of palliative chemotherapy in clearing the blood of CCCs overexpressing diagnostic genes. Clinically the overall lifespan ranged from 5 to 99 months under taxotere. We aimed to investigate the molecular reasons and found that MDR1 overexpression worsened survival by 31%. To the best of our knowledge, this is the first study to show the clinical impact of drug targeting and the counter-effect of drug resistance in CCCs on overall survival. The findings may, therefore, add a novel tool for clinicians in tailoring therapies individually.

OBJECTIVES

• To find the molecular phenotype in circulating cancer cells from patients with prostate cancer (PCa) in order to predict distant metastases. • To determine genes affecting the study endpoints of overall survival and time to progression.

PATIENTS AND METHODS

• Twenty-five urologists in several clinics participated in the study, with 51 patients with metastatic and 77 with non-metastatic PCa. • Molecular analysis was carried out in two forms of circulating cancer cells, cancer cell clusters (CCCs) and individual epithelial cancer cells (CECs). • Gene expression was studied using real-time reverse-transcriptase PCR. • Cycle threshold values were normalized with glyceraldehyde 3-phosphate dehydrogenase in cancer cells and mononucleated cells, yielding comparative specific expression values from the relative quantification method with the help of the standard curve method for each patient and each gene locus.

RESULTS

• Preclinical validation was performed using aggregated and non-aggregated SW480 cells showing the independence of CCCs and CECs. • Prediction of metastases was achieved with five genes showing the highest sensitivity, SOD2, GPX1, AR, cyclin B and bFGF. • The following results were obtained: 94% sensitivity, 65% specificity, 76% positive predictive value and 89% negative predictive value. The prevalence was 63%. Test accuracy was 81% with an odds ratio of 32 (P < 0.001). • Overall survival was worsened by preceding chemotherapies when leaving insufficient GPX1 clearance in blood. • Drug resistance genes were found to worsen the endpoints, among them MDR1 (P = 0.003; hazard ratio: 1.31; 95% CI: 1.09-1.58).

CONCLUSIONS

• SOD2, GPX1 and AR represent a novel biomarker set for circulating cancer cells (clusters and scattered individual cells) in PCa. • The clinical usefulness of these biomarkers ranges from the prediction of clinical tumours to disease prognostication, therapy monitoring and therapy outcome prediction (hormonal therapies, chemotherapies). • The presence of CCCs and CECs after batch isolation allows the addition of genes for intensive studies, e.g. drug resistance.

Role of the angiogenic components, VEGFA, FGF2, OPN and RHOC, in urothelial cell carcinoma of the urinary bladder

The objective of this study was to analyze the expression profile of the angiogenic components, vascular endothelial growth factor-A (VEGFA), basic fibroblast growth factor-2 (FGF2), osteopontin (OPN) and ras homolog gene family, member C (RHOC), in urothelial cell carcinoma (UCC) of the urinary bladder and to examine their role as candidate diagnostic biomarkers. Using qPCR, 77 samples of UCC of the urinary bladder and 77 matched tumor-associated normal samples were investigated to determine the expression of the four angiogenic components. The correlation between gene expression, patient survival and pathological features of the tumors was also examined. The VEGFA and OPN transcript levels were greater in the bladder cancer tissue than in the normal urothelium (P<0.001). Patients with higher VEGFA mRNA levels showed a tendency towards shorter cancer-specific survival. OPN levels showed a gradual increase, the lowest levels being found in non-invasive carcinoma and the highest in muscle invasive tumors. Elevated OPN levels indicated poor prognosis in connection with advanced disease stage (P<0.001). Both superficially invasive and muscle invasive tumors had significantly higher FGF2 levels compared to the control tissues (P=0.018 and P=0.050, respectively). Moreover, FGF2 was significantly higher in the metastatic vs. the non-metastatic tumors (P=0.0097). FGF2 levels exhibited a trend towards a correlation with worse patient survival. RHOC mRNA levels were higher in muscle invasive compared to superficially invasive tumors, as well as in grade III vs. grade I/II tumors. Furthermore, we detected worse overall survival for patients with high RHOC expression levels. VEGFA and FGF2 exhibited the best linear combination in the ROC curves for specificity and sensitivity. Thus, VEGFA and FGF2 may serve as candidate biomarkers for diagnostic purposes. Higher OPN expression may be used as a potential biomarker to predict patient survival relative to advanced tumor stage. However, further studies are required to investigate its role in urinary bladder carcinogenesis.

Phase I/II trial of non-cytotoxic suramin in combination with weekly paclitaxel in metastatic breast cancer treated with prior taxanes

PURPOSE

Suramin, a polysulfonated naphthylurea, inhibits the actions of polypeptide growth factors including acidic and basic fibroblast growth factors (aFGF and bFGF), which confer broad spectrum chemotherapy resistance. We hypothesized that suramin at non-cytotoxic doses in combination with weekly paclitaxel would be well tolerated and demonstrate anti-tumor activity.

METHODS

Women with metastatic breast cancer who had been previously treated with a taxane in the adjuvant or metastatic setting were eligible. The primary objective of the phase I was to determine the dose of intravenous (IV) weekly suramin that resulted in plasma concentrations between 10 and 50 umol/l over 8-48 h (or the target range) in combination with IV 80 mg/m(2) of weekly paclitaxel. The primary objective of the phase II trial was to determine the anti-tumor activity of the dosing regimen defined in phase I. Therapy was continued until disease progression or development of unacceptable toxicity.

RESULTS

Thirty-one patients were enrolled (9: phase I; 22: phase II). In phase I, no dose-limiting toxicities were observed. Pharmacokinetics during the first cycle showed suramin concentrations within the target range for 21 of 24 weekly treatments (88 %). In phase II, the objective response rate (ORR) was 23 % (95 % CI 8-45 %), the median progression-free survival was 3.4 months (95 % CI 2.1-4.9 months), and the median overall survival was 11.2 months (95 % CI 6.6-16.0 months).

CONCLUSIONS

Non-cytotoxic doses of suramin in combination with weekly paclitaxel were well tolerated. The efficacy was below the pre-specified criteria required to justify further investigation.

Targeting angiogenesis in ovarian cancer

Results of standard chemotherapy in ovarian cancer are hampered by the development of drug resistance leading to disease recurrence. This prompted interest in the development of therapies targeting critical pathways responsible for tumor progression. Angiogenesis is a key process that enables ovarian cancer growth and metastasis in the peritoneal space. Its regulation relies on signaling mechanisms initiated by the vascular endothelial growth factor, the platelet-derived growth factor, the fibroblast growth factor, angiopoietins, and others. These pathways are not only important to the modulation of the tumor microenvironment and vasculature, but also control cancer cell proliferation and survival. In this review, we discuss preclinical evidence supporting the rationale for inhibiting these pathways and provide an overview for the clinical development of agents targeting them. Clinical trials evaluating such agents alone and in combination with chemotherapy are ongoing. Early clinical results position antiangiogenic therapy at the forefront of change to the standard treatment of difficult to treat ovarian cancer.

Spotlight on differentially expressed genes in urinary bladder cancer

INTRODUCTION

We previously identified common differentially expressed (DE) genes in bladder cancer (BC). In the present study we analyzed in depth, the expression of several groups of these DE genes.

MATERIALS AND METHODS

Samples from 30 human BCs and their adjacent normal tissues were analyzed by whole genome cDNA microarrays, qRT-PCR and Western blotting. Our attention was focused on cell-cycle control and DNA damage repair genes, genes related to apoptosis, signal transduction, angiogenesis, as well as cellular proliferation, invasion and metastasis. Four publicly available GEO Datasets were further analyzed, and the expression data of the genes of interest (GOIs) were compared to those of the present study. The relationship among the GOI was also investigated. GO and KEGG molecular pathway analysis was performed to identify possible enrichment of genes with specific biological themes.

RESULTS

Unsupervised cluster analysis of DNA microarray data revealed a clear distinction in BC vs. control samples and low vs. high grade tumors. Genes with at least 2-fold differential expression in BC vs. controls, as well as in non-muscle invasive vs. muscle invasive tumors and in low vs. high grade tumors, were identified and ranked. Specific attention was paid to the changes in osteopontin (OPN, SPP1) expression, due to its multiple biological functions. Similarly, genes exhibiting equal or low expression in BC vs. the controls were scored. Significant pair-wise correlations in gene expression were scored. GO analysis revealed the multi-facet character of the GOIs, since they participate in a variety of mechanisms, including cell proliferation, cell death, metabolism, cell shape, and cytoskeletal re-organization. KEGG analysis revealed that the most significant pathway was that of Bladder Cancer (p = 1.5×10(-31)).

CONCLUSIONS

The present work adds to the current knowledge on molecular signature identification of BC. Such works should progress in order to gain more insight into disease molecular mechanisms.

Gene expression pathway analysis to predict response to neoadjuvant docetaxel and capecitabine for breast cancer

Neoadjuvant chemotherapy has been shown to be equivalent to post-operative treatment for breast cancer, and allows for assessment of chemotherapy response. In a pilot trial of docetaxel (T) and capecitabine (X) neoadjuvant chemotherapy for Stage II/III BC, we assessed correlation between baseline gene expression and tumor response to treatment, and examined changes in gene expression associated with treatment. Patients received four cycles of TX. Tumor tissue obtained from Mammotome core biopsies pretreatment (BL) and post-cycle 1 (C1) of TX was FLash frozen and stored at -70 degrees C until processing. Gene expression analysis utilized Affymetrix HG-U133 Plus 2.0 GeneChip arrays. Statistical analysis was performed using BRB Array Tools after RMA normalization. Gene ontology (GO) pathway analysis used random variance t tests with a significance level of P\0.005. For gene categories identified byGO pathway analysis as significant, expression levels of individual genes within those pathways were compared between classes using univariate t tests; those genes with significance level of P\0.05 were reported. PAM50 analyses were performed on tumor samples to investigate biologic subtype and risk of relapse (ROR). Using GO pathway analysis, 39 gene categories discriminated between responders and non-responders,most notably genes involved in microtubule assembly and regulation. When comparing pre- and post-chemotherapy specimens, we identified 71 differentially expressed gene categories, including DNA repair and cell proliferation regulation. There were 45 GO pathways in which the change in expression after one cycle of chemotherapy was significantly different among responders and nonresponders. The majority of tumor samples fell into the basal like and luminal B categories. ROR scores decreased in response to chemotherapy; this change was more evident in samples from patients classified as responders by clinical criteria. GO pathway analysis identified a number of gene categories pertinent to therapeutic response, and may be an informative method for identifying genes important in response to chemotherapy. Larger studies using the methods described here are necessary to fully evaluate gene expression changes in response to chemotherapy.

Pancreatic cancer: pathobiology, treatment options, and drug delivery

Pancreatic cancer is the fourth leading cause of cancer-related deaths in the USA. The high mortality rate is partly due to lack of effective treatments. This review summarizes the pathobiology and current treatment options for pancreatic cancer. Moreover, the review discusses the opportunities of developing novel therapies for pancreatic cancer provided by the progress in understanding the genetic mutations, tumor microenvironment, cancer stem cells, and drug delivery.

Effect of bFGF on invasion of ovarian cancer cells through the regulation of Ets-1 and urokinase-type plasminogen activator

The aim of the study was to explore the role of basic fibroblast growth factor (bFGF) in ovarian cancer progression. This was done by investigating the effects of bFGF on both the secretion of urokinase-type plasminogen activator (uPA) and the invasion of tumor cells in SKOV(3) ovarian cancer cells. Human ovarian cancer cell line SKOV(3) was cultured in vitro. The expression of uPA gene and protein was induced in SKOV(3) cells; the impact of bFGF on the expression of uPA gene in SKOV(3) cells was studied by RT-PCR, and the impact of bFGF on the expression of uPA protein was tested by ELISA. Ets-1 antisense oligonucleotides were transfected into SKOV(3) cells by liposome protocol. The effects of bFGF on Ets-1 expression and the invasion ability of SKOV(3) cells were determined both before and after exposure to different concentrations of bFGF for 24 h. The expression of both uPA gene and protein was induced in SKOV(3) cells, p < 0.05. The expression of uPA was suppressed by Ets-1 antisense oligonucleotides in SKOV(3) cells, p < 0.05. The invasion ability of SKOV(3) cells was increased by 2.3-fold, and this effect was also suppressed by Ets-1 antisense oligonucleotides. bFGF can enhance the invasion ability of ovarian cancer cells in vitro by inducing the expression of uPA, and this effect is also regulated by the transcription factor Ets-1.

Phase I trial of non-cytotoxic suramin as a modulator of docetaxel and gemcitabine therapy in previously treated patients with non-small cell lung cancer

PURPOSE

In preclinical models, non-cytotoxic suramin (concentrations <50 μM) potentiates the activity of multiple chemotherapeutic agents. The present study evaluated the safety and tolerability of suramin in combination with docetaxel or gemcitabine in previously chemotherapy-treated patients with advanced non-small cell lung cancer.

METHODS

Patients received suramin intravenously in combination with either docetaxel on day 1 or gemcitabine on days 1 and 8, of each 21-day treatment cycle. After 3 cycles, patients with partial response (PR) or better continued on the same combination, whereas patients with stable disease (SD) or worse crossed-over to the other combination. Pharmacokinetic analyses were performed before and after each treatment.

RESULTS

Eighteen patients received a total of 79 courses (37 suramin plus docetaxel, 42 suramin plus gemcitabine). The dose-limiting toxicity (DLT) was febrile neutropenia, observed in three of six patients treated with suramin and docetaxel 75 mg/m(2). No DLTs were observed with suramin plus docetaxel 56 mg/m(2) or suramin plus gemcitabine 1,250 mg/m(2). Common adverse events included neutropenia, thrombocytopenia, anemia, fatigue, nausea, vomiting, skin rash, hyperglycemia, and electrolyte abnormalities. The target plasma suramin concentration range of 10-50 μM was achieved in 90% of treatments. Discernable antitumor activity was noted in 11 patients (2 PR, 9 SD).

CONCLUSIONS

Non-cytotoxic suramin, in combination with docetaxel 56 mg/m(2) or gemcitabine 1,250 mg/m(2), was reasonably well-tolerated with a manageable toxicity profile. Target plasma concentrations were correctly predicted by our previously described dosing nomogram. The observed preliminary evidence of antitumor activity encourages evaluation of this strategy in efficacy trials.

Expression of hepatocyte growth factor and basic fibroblast growth factor as prognostic indicators in gastric cancer

We have investigated the correlations among hepatocyte growth factor (HGF) mRNA expression, basic fibroblast growth factor (bFGF) mRNA expression, tumor microvessel density (MVD), and clinical pathological features of gastric cancer in Chinese patients. In situ hybridization was used to detect the expression of HGF and bFGF mRNAs, and immunohistochemistry was used to detect CD34 in 105 gastric cancer tissues and in 20 normal control tissues. The rate of HGF mRNA expression in normal gastric tissues (25%) was significantly lower than that (57.1%) in tumor tissues (P < 0.01). The rates of HGF mRNA and bFGF mRNA expression and MVD in T3-T4 stage tissues were higher than those in T1-T2 stage tissues (P < 0.01); the HGF mRNA expression rate was directly correlated with the bFGF mRNA expression rate (P < 0.05), and they were also directly correlated with MVD (P < 0.01). The mean survival time and the 5-year survival rate of patients who were positive for expression of HGF mRNA and bFGF mRNA and who had a MVD >or= 39.5/0.72 mm(2) were significantly shorter than those who did not express HGF mRNA and bFGF mRNA and who had a MVD <39.5/0.72 mm(2). Both HGF and bFGF may participate in angiogenesis in gastric cancer and may be involved in tumor invasion and metastasis. HGF and bFGF mRNA expression can be used as useful parameters to evaluate the prognosis of gastric cancer.

The role of fibroblast growth factors in tumor growth

Biological processes that drive cell growth are exciting targets for cancer therapy. The fibroblast growth factor (FGF) signaling network plays a ubiquitous role in normal cell growth, survival, differentiation, and angiogenesis, but has also been implicated in tumor development. Elucidation of the roles and relationships within the diverse FGF family and of their links to tumor growth and progression will be critical in designing new drug therapies to target FGF receptor (FGFR) pathways. Recent studies have shown that FGF can act synergistically with vascular endothelial growth factor (VEGF) to amplify tumor angiogenesis, highlighting that targeting of both the FGF and VEGF pathways may be more efficient in suppressing tumor growth and angiogenesis than targeting either factor alone. In addition, through inducing tumor cell survival, FGF has the potential to overcome chemotherapy resistance highlighting that chemotherapy may be more effective when used in combination with FGF inhibitor therapy. Furthermore, FGFRs have variable activity in promoting angiogenesis, with the FGFR-1 subgroup being associated with tumor progression and the FGFR-2 subgroup being associated with either early tumor development or decreased tumor progression. This review highlights the growing knowledge of FGFs in tumor cell growth and survival, including an overview of FGF intracellular signaling pathways, the role of FGFs in angiogenesis, patterns of FGF and FGFR expression in various tumor types, and the role of FGFs in tumor progression.

Biomarker discovery in ovarian cancer

Ovarian cancer is a leading cause of gynecologic cancer death among women. Tumors diagnosed early (in stage I) have a cure rate approaching 90%. However, because specific symptoms and screening tools are lacking, most ovarian cancers are very advanced when finally diagnosed. CA125 expression and pelvic ultrasonography are of limited efficacy in screening, and the search for new, complementary ovarian cancer biomarkers continues. New technology and research techniques have allowed the identification of over 100 possible tumor markers, many of which are still being evaluated for clinical relevance and several of which have entered clinical trials. Here, we review the methods of biomarker discovery, address the significance and functions of newly identified ovarian cancer tumor markers, and provide further insight into the future of ovarian cancer biomarkers.

Basic fibroblast growth factor impact on retinoblastoma progression and survival

PURPOSE

Chemotherapy resistance is a problem in the treatment of advanced retinoblastoma (RB). Since basic fibroblast growth factor (bFGF) is a survival factor for neural precursor cells, bFGF was evaluated as a growth and chemoresistance factor in RB.

METHODS

bFGF expression was analyzed in the LH-betaTag transgenic mouse model of RB and human RB cell lines by immunofluorescence, RT-PCR, and Western blot. Proliferation and apoptosis (TUNEL) assays were performed.

RESULTS

bFGF levels significantly increased during tumorigenesis in transgenic RB, as a function of tumor status (P = 0.005). PCR and confocal microscopy confirmed that the human cell lines and primary tumors expressed bFGF. bFGF was localized to vascular and tumor cells and rarely to glial cells. Exogenous 18-kDa bFGF induced proliferation in two RB cell lines (WERI and Y79). Western blot analysis demonstrated 34-, 22-, and 18-kDa isoforms in transgenic RB and both cell lines. In TUNEL assays, chemoresistance to carboplatin-induced apoptosis was observed in the Y79 line, which expressed a higher ratio of high (34 kDa)- to low-molecular-weight bFGF isoforms, compared with the WERI line. Similar to other bFGF tumor studies, exogenous low-molecular-weight (18 kDa) bFGF (1 ng) significantly enhanced carboplatin-induced apoptosis in the more chemosensitive WERI, but not the chemoresistant Y79 line.

CONCLUSIONS

RB tumors produce significant amounts of bFGF, and the differential production and response to isoforms of bFGF may have implications for invasive tumor growth and chemoresistance.

Role of microRNAs in drug-resistant ovarian cancer cells

OBJECTIVES

Chemotherapy is the preferred therapeutic approach for the therapy of advanced ovarian cancer, but a successful long-term treatment is prevented by the development of drug resistance. Recent works have underlined the involvement of non-coding RNAs, microRNAs (miRNAs) in cancer development, with several conjectures regarding their possible involvement in the evolution of drug resistance. This work was aimed to identify selected microRNAs involved in the development of chemoresistance in ovarian cancer.

METHODS

High-throughput analysis of the miRNA profile in a panel of paclitaxel- (A2780TAX, A2780TC1 and A2780TC3) and cisplatin-resistant (A2780CIS) cells was assessed using a microarray platform and subsequent validation with qPCR and Northern blots. Downstream target validation was performed for miR-130a and the target M-CSF.]

RESULTS

Six miRNAs (let-7e, miR-30c, miR-125b, miR-130a and miR-335) were always diversely expressed in all the resistant cell lines. Let-7e was upregulated in A2780TAX cells, while it was downregulated in the other resistant cell lines. The opposite phenomenon was obtained for miR-125b, which was downregulated in A2780TAX and upregulated in the other cell lines. The miR-30c, miR-130a and miR-335 were downregulated in all the resistant cell lines, thereby suggesting a direct involvement in the development of chemoresistance. Finally downstream target validation was proven for the miR-130a, whose downregulation was linked to the translational activation of the M-CSF gene, a known resistance factor for ovarian cancer.

CONCLUSIONS

Our results indicate that ovarian cancer drug resistance is associated with a distinct miRNA fingerprint, and miRNA microarrays could represent a prognostic tool to monitor the chemotherapy outcome.

Synthesis of bis-diosgenin pyrazine dimers: new cephalostatin analogs

A convenient synthesis for bis-diosgenin pyrazine dimers, cephalostatin analogues is reported. These symmetrical dimeric steroid-pyrazines were obtained by the classical condensation of alpha-amino ketones, the most efficient method for pyrazine ring construction.