Cediranib (AZD2171) in patients with advanced hepatocellular carcinoma: a phase II North Central Cancer Treatment Group Clinical Trial. Am J Clin Oncol. 2012;35:329-333. [PMID: 21422991 DOI: 10.1097/coc.0b013e3182118cdf]

Quantification and analyses of seven tyrosine kinase inhibitors targeting hepatocellular carcinoma in human plasma by QuEChERS and UPLC-MS/MS

Tyrosine kinase inhibitors (TKIs) are commonly used to treat various cancers. Literature suggests that the blood concentration of TKIs strongly correlates with their efficacy and adverse effects. Therefore, establishing a Therapeutic Drug Monitoring (TDM) methodology for TKI drugs is crucial to improving their clinical efficacy and minimizing the treatment-related adverse effects. However, quantifying their concentrations in the plasma using existing methods to avoid potential toxicity is challenging. Herein, seven TKIs, namely sorafenib tosylate, axitinib, erlotinib, cediranib, brivanib, linifanib, and golvatinib, were successfully analyzed in human plasma by following a quick, easy, cheap, effective, rugged, and safe (QuEChERS) pretreatment method combined with ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Briefly, biological samples were extracted using 1 mL of methanol, followed by the sequential addition of 250 mg of anhydrous magnesium sulfate and 25 mg of N-propylethylenediamine (PSA) for salinization and purification by adsorption, respectively. In this study, dovitinib was used as the internal standard. The seven TKIs were detected by the gradient elution method for 4 min in the positive ion electrospray mode. The mobile phase comprised methanol (phase A) and 0.1 % aqueous formic acid solution (phase B) on the Agilent Zorbax RRHD Stablebond Aq, (2.1 × 50 mm; 1.8 μm). Brivanib, linifanib, axitinib, sorafenib tosylate, and golvatinib exhibited good linearity in the range of 5-500 ng/mL, and erlotinib and cediranib exhibited good linearity in the range of 10-1000 ng/mL, with linear correlation coefficients (R2) ≥ 0.99. The limits of detection and quantification were 0.60-0.18 ng/mL and 5-10 ng/mL, respectively. The intraday and interday accuracy values ranged from -6.12 % to 7.31 %, with a precision (RSD) of ≤ 10.57 %. The method was rapid, accurate, specific, simple, reproducible, and suitable for the quantitative determination of the seven TKIs in human plasma.

Insights in Molecular Therapies for Hepatocellular Carcinoma

We conducted a comprehensive review of the current literature of published data and clinical trials (MEDLINE), as well as published congress contributions and active recruiting clinical trials on targeted therapies in hepatocellular carcinoma. Combinations of different agents and medical therapy along with radiological interventions were analyzed for the setting of advanced HCC. Those settings were also analyzed in combination with adjuvant situations after resection or radiological treatments. We summarized the current knowledge for each therapeutic setting and combination that currently is or has been under clinical evaluation. We further discuss the results in the background of current treatment guidelines. In addition, we review the pathophysiological mechanisms and pathways for each of these investigated targets and drugs to further elucidate the molecular background and underlying mechanisms of action. Established and recommended targeted treatment options that already exist for patients are considered for systemic treatment: atezolizumab/bevacizumab, durvalumab/tremelimumab, sorafenib, lenvatinib, cabozantinib, regorafenib, and ramucirumab. Combination treatment for systemic treatment and local ablative treatment or transarterial chemoembolization and adjuvant and neoadjuvant treatment strategies are under clinical investigation.

Role of heterocycles in inhibition of VEGFR-2 - a recent update (2019-2022)

The literature reveals that oncogenic protein kinase inhibition has been proved to be a successful anticancer approach. The vascular endothelial growth factor receptor (VEGFR) kinase plays an important role in angiogenesis and metastasis. VEGFR-2 has an upper hand in the angiogenesis process. Vascular endothelial growth factor activates VEGFR-2 which initiates tumor angiogenesis. In addition, VEGFRs are associated with numerous other diseases. Hence, inhibition of VEGFRs is an attractive approach for cancer treatment. In view of this, researchers designed and discovered small molecular heterocycle-based VEGFR-2 inhibitors and some of them have been approved by the Food and Drug Administration (FDA). However, these VEGFR-2 inhibitors pose adverse side effects such as cardiovascular problems, diarrhea, and renal function impairment. Research indicates that combination of certain pharmacophores exhibits excellent VEGFR inhibitory activity. In particular, combination of heterocycles paved the way to efficient VEGFR inhibitors. In this review, the research focusing on VEGFR inhibitory activity has been discussed along with the structure-activity relationship. In addition to emphasizing the most potent molecule among the set of designed molecules, structural features responsible for such an activity are described. This review may aid in designing potent VEGFR inhibitors.

Unresectable Hepatocellular Carcinoma: A Review of New Advances with Focus on Targeted Therapy and Immunotherapy

With an expected incidence of more than 1 million cases by 2025, liver cancer remains a problem for world health. With over 90% of cases, hepatocellular carcinoma (HCC) is the most prevalent kind of liver cancer. In this review, we presented the range of experimental therapeutics for patients with advanced HCC, the successes and failures of new treatments, areas for future development, the evaluation of dose-limiting toxicity in different drugs, and the safety profile in patients with liver dysfunction related to the underlying chronic liver disease. In addition to the unmet demand for biomarkers to guide treatment decisions and the burgeoning fields of immunotherapy and systemic therapy in hepatocellular carcinoma, the development of old and new drugs, including their failures and current advancements, has been reviewed. This review aims to evaluate the updated optimal clinical treatment of unresectable hepatocellular carcinomas in clinical practice, mainly through targeted therapy. Although surgical treatment can significantly enhance the survival probability of early and intermediate-stage patients, it is unsuitable for most HCC patients due to a lack of donors. Due to their severe toxicity, the few first-line anti-HCC drugs, such as sorafenib, are often reserved for advanced HCC patients for whom other therapies have failed. The second-line drugs are usually alternatives for patients with intolerance or resistance. Consequently, the ongoing growth of possible preclinical drugs and studies on miRNAs, lncRNAs, and numerous other signaling pathway targets for developing novel drugs may introduce additional treatment prospects for HCC.

Potential therapeutic strategies to combat HCC

Hepatocellular carcinoma (HCC) is a complex, life threatening and most common neoplasm in the world. HCC tumors are genetically and phenotypically heterogeneous and involve various molecular mechanisms and stimulation of several signaling pathways such as Vascular Endothelial Growth Factor, Epidermal Growth Factor Receptors (EGFR), Insulin growth factor, Ras/extracellular signal-stimulated kinase, mammalian goal of rapamycin (mTOR), c-mesenchymal-epithelial transition factor-1 (c-Met), Hedgehog, Wnt and apoptotic signaling. Lately, in patient's multi-kinase cascade blockers such as sorafenib, selumetinib and regorafenib have increased survival rate of progressive HCC. This development presents a step forward towards the therapy of liver cancer infection and attests that molecular systemic rehabilitations can be useful in HCC treatment. The development of these systemic therapeutic agents has further expanded the research area for surplus molecular mediators to auxiliary increase cure rate of patients. This article reviews the complete consideration of focus on cascades, current enduring clinical tests by means of HCC therapeutic mediators, and imminent prospects in the cure of HCC.

Anti-Hepatocellular Carcinoma Biomolecules: Molecular Targets Insights

This report explores the available curative molecules directed against hepatocellular carcinoma (HCC). Limited efficiency as well as other drawbacks of existing molecules led to the search for promising potential alternatives. Understanding of the cell signaling mechanisms propelling carcinogenesis and driven by cell proliferation, invasion, and angiogenesis can offer valuable information for the investigation of efficient treatment strategies. The complexity of the mechanisms behind carcinogenesis inspires researchers to explore the ability of various biomolecules to target specific pathways. Natural components occurring mainly in food and medicinal plants, are considered an essential resource for discovering new and promising therapeutic molecules. Novel biomolecules normally have an advantage in terms of biosafety. They are also widely diverse and often possess potent antioxidant, anti-inflammatory, and anti-cancer properties. Based on quantitative structure-activity relationship studies, biomolecules can be used as templates for chemical modifications that improve efficiency, safety, and bioavailability. In this review, we focus on anti-HCC biomolecules that have their molecular targets partially or completely characterized as well as having anti-cancer molecular mechanisms that are fairly described.

Targeting molecular signal transduction pathways in hepatocellular carcinoma and its implications for cancer therapy

Hepatocellular carcinoma is a substantial health concern. It is currently the third dominating cause of mortality associated with cancer worldwide. The development of hepatocellular carcinoma is an intricate process that encompasses the impairment of genetic, epigenetic, and signal transduction mechanisms contributing to an aberrant metabolic system, enabling tumorigenesis. Throughout the past decade, research has led to the revelation of molecular pathways implicated in the progression of this notorious disorder. The altered signal transduction pathways, such as the mitogen-activated protein kinase pathway, phosphoinositol 3-kinase/protein kinase B/mammalian target of rapamycin pathway, WNT/β-catenin pathway, hepatocyte growth factor/c-MET pathway, and just another kinase/signal transducers and activators of transcription signaling pathway is of much therapeutic significance, as targeting them may avail to revert, retard or avert hepatocarcinogenesis. The present review article sums up the contemporary knowledge of such signaling mechanisms, including their therapeutic targets and betokens that novel and efficacious therapies can be developed only by the keen understanding of their character in hepatocarcinogenesis. In additament, we address the role of consequential therapeutic agents and preclinical nondrug therapies known for combating hepatocarcinogenesis.

Design, molecular docking, in vitro, and in vivo studies of new quinazolin-4(3H)-ones as VEGFR-2 inhibitors with potential activity against hepatocellular carcinoma

A series of new VEGFR-2 inhibitors were designed, synthesized and evaluated for their anti-proliferative activities against hepatocellular carcinoma (HepG-2 cell line). Compound 29_b (IC₅₀ = 4.33 ± 0.2 µg/ml) was found to be the most potent derivative as it has showed to be more active than doxorubicin (IC₅₀ = 4.50 ± 0.2 µg/ml) and 78% of sorafenib activity (IC₅₀ = 3.40 ± 0.25 µg/ml). The inhibitory profiles against VEGFR-2 were also assessed for the most promising candidates (16_b, 20_c, 22_b, 24_a, 24_b, 28_c, 28_e, 29_a, 29_b and 29_c). Compounds 29_b, 29_c and 29_a exhibited potent inhibitory activities towards VEGFR-2 at IC₅₀ values of 3.1 ± 0.04, 3.4 ± 0.05 and 3.7 ± 0.06 µM, respectively, comparing sorafenib (IC₅₀ = 2.4 ± 0.05 µM). Furthermorer, compound 29_b induced apoptosis and arrested the cell cycle growth at G2/M phase. Additionally, in vivo antitumor experiments revealed that compounds 29_b and 29_c have significant tumor growth inhibition. The test of immuno-histochemical expression of activated caspase-3 revealed that there is a time-dependent increase in cleaved caspase-3 protein expression upon exposure of HepG-2 cells to compound 29_b. Moreover, the fibroblastic proliferative index test revealed that compound 29_b could attenuate liver fibrosis. Docking studies also supported the results concluded from the biological screening via prediction of the possible binding interactions of the target compounds with VEGFR-2 active sites using the crystal structure of VEGFR-2 downloaded from the Protein Data Bank, (PDB ID: 2OH4) using Discovery Studio 2.5 software. Further structural optimization of the most active candidates may serve as a useful strategy for getting new lead compounds in search for powerful and selective antineoplastic agents.

Novel molecular targets in hepatocellular carcinoma

Globally, hepatocellular carcinoma (HCC) is a leading cause of cancer and cancer-related deaths. The therapeutic efficacy of locoregional and systemic treatment in patients with advanced HCC remains low, which results in a poor prognosis. The development of sorafenib for the treatment of HCC has resulted in a new era of molecular targeted therapy for this disease. However, the median overall survival was reported to be barely higher in the sorafenib treatment group than in the control group. Hence, in this review we describe the importance of developing more effective targeted therapies for the management of advanced HCC. Recent investigations of molecular signaling pathways in several cancers have provided some insights into developing molecular therapies that target critical members of these signaling pathways. Proteins involved in the Hedgehog and Notch signaling pathways, Polo-like kinase 1, arginine, histone deacetylases and Glypican-3 can be potential targets in the treatment of HCC. Monotherapy has limited therapeutic efficacy due to the development of inhibitory feedback mechanisms and induction of chemoresistance. Thus, emphasis is now on the development of personalized and combination molecular targeted therapies that can serve as ideal therapeutic strategies for improved management of HCC.

Exploration of carbamide derived pyrimidine-thioindole conjugates as potential VEGFR-2 inhibitors with anti-angiogenesis effect

The development of new small molecules from known structural motifs through molecular hybridization is one of the trends in drug discovery. In this connection, we have combined the two pharmacophoric units (pyrimidine and thioindole) in a single entity via molecular hybridization strategy along with introduction of urea functionality at C2 position of pyrimidine to increase the efficiency of H-bonding interactions. Among the synthesized conjugates 12a-aa, compound 12k was found to exhibit significant IC₅₀ values 5.85, 7.87, 6.41 and 10.43 μM against MDA-MB-231 (breast), HepG2 (liver), A549 (lung) and PC-3 (prostate) cancer cell lines, respectively. All these compounds were further evaluated for their inhibitory activities against VEGFR-2 protein. The results specified that among the tested compounds, 12d, 12e, 12k, 12l, 12p, 12q, 12t and 12u prominently suppressed VEGFR-2, with IC₅₀ values of 310-920 nM in association to the positive control (210 nM). Angiogenesis inhibition was evident by tube formation assay in HUVECs and cell-invasion by transwell assay. The mechanism of cellular toxicity on MDA-MB-231 was found through depolarisation of mitochondrial membrane potential, increased ROS production and subsequent DNA damage resulting in apoptosis induction. Moreover, clonogenic and wound healing assays designated the inhibition of colony formation and cell migration by 12k in a dose-dependent manner. Molecular docking studies also shown that compound 12k capably intermingled with catalytically active residues GLU-885, ASP-1046 of the VEGFR-2 through hydrogen-bonding interactions.

Systemic Management for Advanced Hepatocellular Carcinoma: A Review of the Molecular Pathways of Carcinogenesis, Current and Emerging Therapies, and Novel Treatment Strategies

Hepatocellular carcinoma (HCC) arises from a number of cirrhosis-related and non-cirrhosis-related exposures and is one of the leading causes of cancer-related deaths worldwide. Achieving a durable cure currently relies on either resection or transplantation, but since most patients will be diagnosed with inoperable disease, there is great interest in achieving more effective systemic therapies. At a molecular level, HCC is heterogeneous, but initial treatment strategies, including the use of multi-targeted tyrosine kinase inhibitors and checkpoint inhibitors, have been fairly homogenous, depending on general host factors and overall tumor burden rather than specific molecular signatures. Over the past 2 decades, however, there has been significant success in identifying key molecular targets, including driver mutations involving the telomerase reverse transcriptase, p53, and beta-catenin genes, and significant work is now being devoted to translating these discoveries into the development of robust and well-tolerated targeted therapies. Furthermore, multi-modal therapies have also begun to emerge, harnessing possible synergism amongst a variety of different treatment classes. As the findings of these landmark trials become available over the next several years, the landscape of the systemic management of advanced HCC will change significantly.

Treatment options after sorafenib failure in patients with hepatocellular carcinoma

Second line therapy after failure of sorafenib continues to be under study. Prognosis of hepatocellular carcinoma is measured in months, with median overall survival reaching 10.7 months with sorafenib. Because of the modest net benefit sorafenib has contributed, and rising incidence of hepatocellular carcinoma in the world, continued efforts are ongoing to look for efficient upfront, second line, or combination therapies. Herein we review the most relevant to date published literature on treatment options beyond sorafenib, reported studies, ongoing investigational efforts, and possibilities for future studies in advanced hepatocellular carcinoma.

Antiangiogenic agents after first line and sorafenib plus chemoembolization: a systematic review

Transarterial chemoembolization (TACE) is the standard treatment for intermediate stage, although the combination of TACE with sorafenib may theoretically benefit HCC patients in intermediate stage. Owing to the significant antiangiogenic effect of sorafenib and the limitation of TACE, it is rational to combine them. Though the strategy of combining TACE and sorafenib has been increasingly used in patients with unresectable HCC but the current evidence is controversial and its clinical role has not been determined yet.

In first-line therapy, patients receiving sorafenib had increased overall survival and progression free survival. Therefore several antiangiogenic agents have entered clinical studies on HCC, many with negative results. This review discusses the current drug development for patients with HCC and role of TACE plus sorafenib.

Targeting the vasculature in hepatocellular carcinoma treatment: Starving versus normalizing blood supply

Traditional treatments for intermediate or advanced stage hepatocellular carcinoma (HCC) such as transarterial chemoembolization (TACE) and anti-angiogenesis therapies were developed to starve tumor blood supply. A new approach of normalizing structurally and functionally abnormal tumor vasculature is emerging. While TACE improves survival in selected patients, the resulting tumor hypoxia stimulates proliferation, angiogenesis, treatment resistance and metastasis, which limits its overall efficacy. Vessel normalization decreases hypoxia and improves anti-tumor immune infiltrate and drug delivery. Several pre-clinical agents aimed at normalizing tumor vasculature in HCC appear promising. Although anti-angiogenic agents with vessel normalizing potential have been trialed in advanced HCC with modest results, to date their primary intention had been to starve the tumor. Judicious use of anti-angiogenic therapies is required to achieve vessel normalization yet avoid excessive pruning of vessels. This balance, termed the normalization window, is yet uncharacterized in HCC. However, the optimal class, dose and schedule of vascular normalization agents, alone or in combination with other therapies needs to be explored further.

Emerging tyrosine kinase inhibitors for the treatment of hepatocellular carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) is the fifth most diagnosed cancer in the world and the third leading cause of death. Unfortunately, when diagnosed two thirds of patients have an advanced disease for which only palliative treatment can be proposed and most likely systemic therapy. Areas covered: As of today only one systemic therapy is validated in the treatment of advanced HCC, a tyrosine kinase inhibitor (TKI): Sorafenib. Treatment options are therefore lacking. With the advent of Sorafenib other TKIs have been studied with some disappointing results. Many explanations can be found to the failure of these tested TKIs such as the underlying cirrhosis leading to rapidly serious adverse events, or trial design imperfections. Expert opinion: Taking into account these failures, new trials with more appropriate designs have led to recent success with multi-target TKIs (Regorafenib and Lenvatinib). This multi-target approach allows to overcome the molecular heterogeneity of advanced HCC which is associated with multiple simultaneously dysregulated signaling pathways. On the contrary, another lead is to study target a specific TKI such as c-MET inhibitors or TGFβR inhibitors in HCC sub-populations with promising results in early phase trials. These results will have to be validated in the ongoing phase III trials.

Systemic therapy for advanced hepatocellular carcinoma: an update

Advanced hepatocellular carcinoma (HCC) is a deadly disease with few systemic therapeutic options. Sorafenib is the only agent to be FDA approved for the first-line treatment of patients with HCC. This drug increases overall survival (OS) by 3 months compared with placebo (10.7 months with sorafenib vs. 7.7 months with placebo). More recently, the RESORCE trial demonstrated efficacy of regorafenib in the second-line treatment of HCC: OS was increased from 7.8 months with placebo to 10.6 months with regorafenib after patients experienced disease progression on sorafenib. However, there is still an unmet need for effective systemic therapy of patients with advanced HCC. Numerous genetic pathways have been studied along with drugs to target these pathways but, thus far, drugs targeting cell proliferation, metastasis, angiogenesis, and metabolite use have been studied with minimal success. HCC can be divided into two subclasses: proliferative and non-proliferative, each dependent on separate pathways. HCC can be caused by alcoholic cirrhosis, hepatitis C virus (HCV), and hepatitis B virus (HBV); however no etiology-specific therapies have been demonstrated. Immunotherapy is currently being assessed in clinical trials and is demonstrating some efficacy. More research is needed to determine the most essential pathways to target in the war against this deadly cancer.

Angiogenesis Inhibitors for the Treatment of Hepatocellular Carcinoma

Background: Angiogenesis inhibitors have become an important therapeutic approach in the treatment of hepatocellular carcinoma (HCC) patients. The therapeutic inhibition of angiogenesis of Sorafenib in increasing overall survival of patients with HCC is a fundamental element of the treatment of this disease. Considering the heterogeneous aspects of HCC and to boost therapeutic efficacy, prevail over drug resistance and lessen toxicity, adding antiangiogenic drugs to antiblastic chemotherapy (AC), radiation therapy or other targeted drugs have been evaluated. The matter is additionally complicated by the combination of antiangiogenesis with further AC or biologic drugs. To date, no planned approach to understand which patients are more responsive to a given type of antiangiogenic treatment is available.

Conclusion: Large investments in the clinical research are essential to improve treatment response and minimize toxicities for patients with HCC. Future investigations will need to focus on utilizing patterns of genetic information to classify HCC into groups that display similar prognosis and treatment sensitivity, and combining targeted therapies with AC producing enhanced anti-tumor effect. In this review the current panel of available antiangiogenic therapies for the treatment of HCC have been analyzed. In addition current clinical trials are also reported herein.

Hepatocellular Carcinoma: Past and Future of Molecular Target Therapy

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer related mortality worldwide. The incidence of HCC has been increasing annually. Viral infection, alcohol usage, and other causes of cirrhosis have been identified as major risk factors for HCC development. The underlying pathogenesis has not been as well defined. There have been multiple hypotheses to the specific mechanisms of hepatocarcinogenesis and they share the common theme of chronic inflammation, increase oxidative stress, and genomic alteration. Therapeutic options of HCC have been primarily local and/or regional including transplantation, resection, and radial frequency ablation, chemoembolization or radio-embolization. For unresectable or metastatic disease, the options are limited. Conventional chemotherapeutic options have been noted to have limited benefit. Sorafenib has been the one and only systemic therapy which has demonstrated modest overall survival benefit. This has led to more extensive research with focus on targeted therapy. Numerous pre-clinical and early phase clinical studies have been noted but failed to show efficacy in later phase clinical trials. In an effort to identify new potential therapeutic options, new understanding of underlying pathways to hepatocarcinogenesis should be one of the main focuses. This leads to development of more molecularly targeted agents to specific pathways, and immunotherapy. This article provides a review of major studies of molecular targeted agents which attempts to target these specific pathways in HCC.

Hypertension in cancer patients treated with anti-angiogenic based regimens

New anti-cancer drugs that inhibit the vascular endothelial growth factor (VEGF) signaling pathway are highly effective in the treatment of solid tumors, however concerns remain regarding their cardiovascular safety. The most common side effect of VEGF signaling pathway (VSP) inhibition is the development of systemic hypertension. We review the incidence, possible mechanisms, significance and management of hypertension in patients treated with VSP inhibitors.

Hepatocellular carcinoma treatment over sorafenib: epigenetics, microRNAs and microenvironment. Is there a light at the end of the tunnel?

INTRODUCTION

Sorafenib is currently the only approved therapy in hepatocellular carcinoma (HCC). Alternative first- and second-line treatments are a significant unmet medical need, and several biologic agents have been tested in recent years, with poor results. Therefore, angiogenic pathways and the cytokine cascade remain possible targets in HCC. Recent studies suggest a role of epigenetic processes, associated with the initiation and development of HCC. In this field, DNA methylation, micro-RNAs (miRNAs) and tumor microenvironment cells became a possible new target for HCC treatment.

AREAS COVERED

This review explains the possible role of DNA methylation and histone deacetylase inhibitors as predictive biomarkers and target therapy, the extensive world of the promising miRNA blockade strategy, and the recent strong evidence of correlation between HCC tumors and peritumoral stroma cells. The literature and preclinic/clinic data were obtained through an electronic search.

EXPERT OPINION

Future research should aim to understand how best to identify patient groups that would benefit most from the prescribed therapy. To overcome the 'therapeutic stranding' of HCC, a possible way out from the current therapeutic tunnel might be to evaluate the major epigenetic and genetic processes involved in HCC carcinogenesis, not underestimating the tumor microenvironment and its 'actors' (angiogenesis, immune system, platelets). We are only at the start of a long journey towards the elucidation of HCC molecular pathways as therapeutic targets. Yet, currently this path appears to be the only one to cast some light at the end of the tunnel.

Chemotherapy and target therapy for hepatocellular carcinoma: New advances and challenges

Primary liver cancer is one of the commonest causes of death. Hepatocellular carcinoma (HCC) accounts for 90% of primary liver cancers. For patients with unresectable or metastatic HCC, conventional chemotherapy is of limited or no benefit. Sorafenib is the only systemic treatment to demonstrate a statistically significant but modest overall survival benefit, leading to an era of targeted agents. Many clinical trials of targeted drugs have been carried out with many more in progress. Some drugs like PTK787 showed potential benefits in the treatment of HCC. Despite these promising breakthroughs, patients with HCC still have a dismal prognosis. Recently, both a phase III trial of everolimus and a phase II clinical trial of trebananib failed to demonstrate effective antitumor activity in advanced HCC. Sorafenib still plays a pivotal role in advanced HCC, leading to further explorations to exert its maximum efficacy. Combinations targeted with chemotherapy or transarterial chemoembolization is now being tested and might bring about advances. New targeted agents such as mammalian target of rapamycin inhibitors are under investigation, as well as further exploration of the mechanism of hepatocarcinogenesis.

Receptor tyrosine kinase inhibitors: Are they real tumor killers?

Inhibiting tumor growth by targeting the tumor vasculature was first proposed by Judah Folkman almost 40 years ago. Since then, different approaches and numerous drugs and agents have been developed to achieve this goal, either with the aim of inhibiting tumor neoangiogenesis or normalizing the tumor vasculature. Among the most promising therapeutic targets are receptor tyrosine kinases (RTKs), some of which are predominantly expressed on tumor endothelial cells, although they are sometimes also present on tumor cells. The majority of RTK inhibitors investigated over the past two decades competes with ATP at the active site of the kinase and therefore block the phosphorylation of intracellular targets. Some of these drugs have been approved for therapy, whereas others are still in clinical trials. Here, we discuss the scientific basis, current status, problems and future prospects of RTK inhibition in anti-tumor therapy.

Targeting the tumor stroma in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common and deadly cancers worldwide. In ninety percent of the cases it develops as a result of chronic liver damage and it is thus a typical inflammation-related cancer characterized by the close relation between the tumor microenvironment and tumor cells. The stromal environment consists out of several cell types, including hepatic stellate cells, macrophages and endothelial cells. They are not just active bystanders in the pathogenesis of HCC, but play an important and active role in tumor initiation, progression and metastasis. Furthermore, the tumor itself influences these cells to create a background that is beneficial for sustaining tumor growth. One of the key players is the hepatic stellate cell, which is activated during liver damage and differentiates towards a myofibroblast-like cell. Activated stellate cells are responsible for the deposition of extracellular matrix, increase the production of angiogenic factors and stimulate the recruitment of macrophages. The increase of angiogenic factors (which are secreted by macrophages, tumor cells and activated stellate cells) will induce the formation of new blood vessels, thereby supplying the tumor with more oxygen and nutrients, thus supporting tumor growth and offering a passageway in the circulatory system. In addition, the secretion of chemokines by the tumor cells leads to the recruitment of tumor associated macrophages. These tumor associated macrophages are key actors of cancer-related inflammation, being the main type of inflammatory cells infiltrating the tumor environment and exerting a tumor promoting effect by secreting growth factors, stimulating angiogenesis and influencing the activation of stellate cells. This complex interplay between the several cell types involved in liver cancer emphasizes the need for targeting the tumor stroma in HCC patients.

Dissecting signaling pathways in hepatocellular carcinoma: new perspectives in medical therapy

Prognosis of patients with advanced hepatocellular carcinoma (HCC) is poor and is largely influenced by associated liver comorbidities. Moreover, effective treatment alternatives are limited; with the exception of the multitargeted inhibitor sorafenib, established options in the treatment of advanced HCC no longer amenable with ablative or locoregional procedures are lacking. In light of the limited efficacy of chemotherapy in this setting, great efforts have been made in the definition of targetable molecular pathways with a central role in the progression of HCC. Targeting angiogenesis, growth factor receptors, intracellular transduction pathways, or mechanisms of gene-expression regulation represents the main way to improve patient outcome. At the same time, identifying clinical and biological factors, which may help selecting patients with higher chances of benefit, is essential in order to hasten drug development and maximize treatment efficacy.

Efficacy and safety of the FOLFOX4 regimen versus doxorubicin in Chinese patients with advanced hepatocellular carcinoma: a subgroup analysis of the EACH study

BACKGROUND

The EACH study assessed the efficacy of oxaliplatin, 5-fluorouracil, and leucovorin (the FOLFOX4 regimen) compared with doxorubicin alone in terms of overall survival (OS), progression-free survival (PFS), and safety in patients with advanced hepatocellular carcinoma (HCC). We present the results of this study in Chinese patients.

METHODS

In a multicenter, open-label, randomized, phase III study (NCT00471965), 371 patients (279 patients from the People's Republic of China) were randomized 1:1 to receive either FOLFOX4 or doxorubicin until disease progression, intolerable toxicity, death, or surgical resection.

RESULTS

Baseline characteristics of the Chinese patients enrolled in the study were similar for the 2 treatment groups and in comparison with the whole EACH cohort. Median OS at the prespecified time point of treatment was 5.7 months with FOLFOX4 and 4.3 months with doxorubicin (hazard ratio [HR]: 0.74; 95% confidence interval [CI]: 0.55-0.98; p = .03). At the end of the follow-up period, median OS was 5.9 months with FOLFOX4 and 4.3 months with doxorubicin (HR: 0.75; 95% CI: 0.58-0.98; p = .03). Median PFS was 2.4 months and 1.7 months in the FOLFOX4 and doxorubicin groups, respectively (HR: 0.55; 95% CI: 0.45-0.78; p = .0002). The response rate (RR) and disease control rate (DCR) were significantly higher in the FOLFOX4 group than in the doxorubicin group (RR: 8.6% vs. 1.4%, p = .006; DCR: 47.1% vs. 26.6%, p = .0004). Hematological toxicity was more frequently reported in the FOLFOX4 group.

CONCLUSION

For Chinese HCC patients enrolled in the EACH study, FOLFOX4 significantly improved the RR and DCR and prolonged survival compared with doxorubicin. Systemic chemotherapy with oxaliplatin-based regimens may play an important role in the treatment of Chinese patients with advanced HCC.

Systemic therapy of hepatocellular carcinoma: Current status and future perspectives

The management of hepatocellular carcinoma (HCC) has substantially changed in the past few decades, the introduction of novel therapies (such as sorafenib) have improved patient survival. Nevertheless, HCC remains the third most common cause of cancer-related deaths worldwide. Decision-making largely relies on evidence-based criteria, as showed in the US and European clinical practice guidelines, which endorse five therapeutic recommendations:resection; transplantation; radiofrequency ablation; chemoembolization; and sorafenib. Many molecularly targeted agents that inhibit angiogenesis, epidermal growth factor receptor, and mammalian target of rapamycin are at different stages of clinical development in advanced HCC. Future research should continue to unravel the mechanism of hepatocarcinogenesis and to identify key relevant molecular targets for therapeutic intervention. Identification and validation of potential surrogate and predictive biomarkers hold promise to individualize patient’s treatment to maximize clinical benefit and minimize the toxicity and cost of targeted agents.

Targeted therapy in gastrointestinal malignancies

Increased understanding of cancer pathogenesis has identified several pathways that serve as potential targets for novel targeted agents in development. The selection of targeted cancer therapy based on biomarkers has instigated a new era of personalized medicine and changed the way we practice oncology. Many targeted agents are approved for treatment of gastrointestinal malignancies most targeting tumor angiogenesis, and many more are in different phases of development. Here we briefly summarize nine different targeted agents that are approved currently in the U.S. and several other agents currently being studied in various gastrointestinal cancers.

Systemic therapy for hepatocellular carcinoma

Optimal treatment of hepatocellular carcinoma (HCC) is clinically challenging. Systemic treatment for advanced HCC was limited until the approval of sorafenib. This discovery resulted in the advent of many clinical trials. An ongoing Phase III trial is examining the benefit of adjuvant sorafenib. Utilization of doxorubicin-eluting bead embolization may offer safer treatment in eligible HCC patients. The use of systemic treatment peritransarterial chemoembolization is also being investigated. Many targeted therapies are being explored as first-/second-line treatment options in advanced HCC. The potential benefit of c-MET inhibitors, particularly in those with advanced, MET high expression HCC, may result in new systemic patient-directed targeted medicinal approaches. Remaining dilemmas query the appropriate management of patients with advanced Child-Pugh B, HCC and those recurring post-transplant.

Advanced unresectable hepatocellular carcinoma: new biologics as fresh ammunition or clues to disease understanding?

PURPOSE OF REVIEW

Hepatocellular carcinoma (HCC) is a prevalent malignancy associated with a guarded prognosis. At present, sorafenib is the only approved systemic therapy for patients with advanced disease. The effect of sorafenib on overall survival is modest and limited in time by the occurrence of drug resistance.

RECENT FINDINGS

Together with the increasing knowledge of molecular pathways involved in HCC, targeted molecules have been developed and tested in first and second line following sorafenib. These include antiangiogenic drugs, as well as biologicals inhibiting cell proliferation and survival. Recent phase III trials investigated sunitinib, linifanib, brivanib and erlotinib, but none of them were found superior to sorafenib. New findings in mechanisms of drug resistance create opportunities in the treatment of sorafenib-refractory disease, with cMET inhibition as the most promising approach. This article reviews the pathways involved in HCC and their targets as well as potential strategies for drug development in the future.

SUMMARY

Advanced HCC has been the subject of intensive clinical research following the success of sorafenib. Despite many failures, some agents show promising results in phase II trials. Targeting new pathways, using multidrug regimens and tailoring treatment guided by predictive markers should allow new successes.

Molecular targeted therapy for hepatocellular carcinoma: current and future

Hepatocellular carcinoma (HCC) is one of the most frequent tumors worldwide. The majority of HCC cases occur in patients with chronic liver disease. Despite regular surveillance to detect small HCC in these patients, HCC is often diagnosed at an advanced stage. Because HCC is highly resistant to conventional systemic therapies, the prognosis for advanced HCC patients remains poor. The introduction of sorafenib as the standard systemic therapy has unveiled a new direction for future research regarding HCC treatment. However, given the limited efficacy of the drug, a need exists to look beyond sorafenib. Many molecular targeted agents that inhibit different pathways involved in hepatocarcinogenesis are under various phases of clinical development, and novel targets are being assessed in HCC. This review aims to summarize the efforts to target molecular components of the signaling pathways that are responsible for the development and progression of HCC and to discuss perspectives on the future direction of research.

Systemic therapy for hepatocellular carcinoma (HCC): from bench to bedside

Primary liver cancer is the fifth most common cancer worldwide and the third most common cause of cancer mortality. For patients with early resectable disease, surgical resection or transplantation is considered a potentially curative modality for hepatocellular carcinoma (HCC); on the other hand, for patients with unresectable or metastatic disease, treatment is essentially palliative and prior to the approval of sorafenib, there was no globally approved systemic treatment for patients presenting with unresectable or metastatic HCC. Sorafenib is the only systemic treatment to demonstrate a statistically significant but modest overall survival benefit in a large phase III trial. Thus, novel systemic approaches represent a high unmet medical need in advanced HCC. In this review article, we will try to take a journey through the history of systemic therapeutic options for HCC passing through the current standard options and exploring the potential new systemic options for this disease.

Clinical trials in hepatocellular carcinoma: an update

The success of sorafenib has spurred an explosive increase of clinical trials testing novel molecular targets and other agents in the treatment of hepatocellular carcinoma (HCC). The paradigm of the studies has been characterized by three noticeable changes. First, the molecular targets of interest have expanded from angiogenesis to cancer cell-directed oncogenic signaling pathways for advanced HCC treatment. Agents targeting EGFR, FGFR, PI3K/Akt/mTOR, TGF-β, c-Met, MEK, IGF signaling, and histone deacetylase have been actively explored. Second, the target indication has shifted from advanced stage to early or intermediate stages of disease. The feasibility of combining locoregional therapies and targeted agents, and the use of novel agents after curative treatments are currently under active investigation. Finally, the therapeutic strategy has shifted from monotherapy to combination targeted therapy. We aim to provide a comprehensive overview of newly disclosed and ongoing clinical trials for the treatment of HCC.

Systemic therapy and synergies by combination

After years of therapeutic nihilism due to the inefficacy of conventional cytotoxic chemotherapy, the multikinase inhibitor sorafenib was the first agent to demonstrate a significant improvement in the survival of patients with advanced hepatocellular carcinoma (HCC). However, survival benefits on sorafenib treatment remain modest in clinical practice and developing more effective systemic therapies is challenging. No other targeted agent or regimen has proven efficacy to improve survival in a phase III trial in the first- or second-line setting, and no standard treatment option currently exists outside of clinical trials for patients with acquired resistance or intolerance to sorafenib. In contrast to other malignancies, no oncogene addiction has been identified in hepatocarcinogenesis thus far, which may explain why currently tested agents do not achieve sustained partial or complete response in the majority of patients. Several agents with mainly antiangiogenic properties are currently in phase II and III development, including brivanib, ramucirumab, everolimus, tivantinib and resminostat. In addition, the role of molecularly targeted therapy (MTT) in earlier stages of the disease in combination with transcatheter arterial chemoembolization or in the adjuvant setting after potentially curative approaches is under investigation. The identification of the key driver mutations and the assessment of relevant targets for specific subpopulations of patients according to their biomarker-based profile will hopefully lead to a more personalized medicine. This article attempts to provide a concise overview on recent developments of MTT in the phase II-III setting in advanced HCC with an additional focus on synergistic combinations and combined treatment approaches.

The evolving landscape of therapeutic drug development for hepatocellular carcinoma

Currently, only one drug, sorafenib, is FDA approved for the treatment of advanced hepatocellular carcinoma (HCC), achieving modest objective response rates while still conferring an overall survival benefit. Unlike other solid tumors, no oncogenic addiction loops have been validated as clinically actionable targets in HCC. Outcomes of HCC could potentially be improved if critical molecular subclasses with distinct therapeutic vulnerabilities can be identified, biomarkers that predict recurrence or progression early can be determined and key epigenetic, genetic or microenvironment drivers that determine best response to a specific targeting treatment can be uncovered. Our group and others have examined the molecular heterogeneity of hepatocellular carcinoma. We have developed a panel of patient derived xenograft models to enable focused pre-clinical drug development of rationally designed therapies in specific molecular subgroups. We observed unique patterns, including synergies, of drug activity across our molecularly diverse HCC xenografts, pointing to specific therapeutic vulnerabilities for individual tumors. These efforts inform clinical trial designs and catalyze therapeutic development. It also argues for efficient strategic allocation of patients into appropriate enriched clinical trials. Here, we will discuss some of the recent important therapeutic studies in advanced HCC and also some of the potential strategies to optimize clinical therapeutic development moving forward.

Antiangiogenic therapies for advanced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a significant cause of death worldwide. HCC is a highly vascular tumor, and proangiogenic cytokines such as vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and fibroblast growth factor may play crucial roles in this disease. Sorafenib, a multikinase inhibitor that blocks VEGF and PDGF signaling, was the first systemic therapy to demonstrate improved survival in patients with advanced HCC. Several other drugs targeting VEGF are in development. Because of the anticipation of eventual resistance to anti-VEGF therapies, drugs that also target alternative proangiogenic pathways are being investigated. Recent clinical and preclinical data along with ongoing studies are reviewed.

Impact of restricting access to high-cost medications for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a leading cause of cancer death globally, and its incidence is increasing in the West, including the UK, with the increasing burden of chronic liver disease. Until recently, systemic treatment options for advanced disease were limited. However, randomized clinical trials have demonstrated that the multikinase inhibitor sorafenib prolongs survival in appropriately selected patients, and this drug has become the standard of care for patients with advanced HCC. However, a single-technology appraisal by the NICE recommended that the UK National Health Service should not fund sorafenib on the grounds of cost-effectiveness. A number of other novel agents and combinations are currently in clinical trials, the results of which may further expand the treatment options and indications for systemic therapy in HCC. This review discusses the impact of restricting access to high-cost medications for patients with HCC in the UK, and describes potential strategies and future directions that may improve the cost-effectiveness of such drugs. It also describes the potential impact, pending national guidance, of variations in local funding decision-making on patient outcomes.

Efficacy, safety, pharmacokinetics, and biomarkers of cediranib monotherapy in advanced hepatocellular carcinoma: a phase II study

PURPOSE

We conducted a single-arm phase II study of cediranib, a pan-VEGFR tyrosine kinase inhibitor, in patients with advanced hepatocellular carcinoma (HCC).

EXPERIMENTAL DESIGN

Patients with histologically confirmed measurable advanced HCC and adequate hematologic, hepatic, and renal functions received cediranib 30-mg orally once daily (4 weeks/cycle). The primary endpoint was progression-free survival (PFS) rate at 3 months. Other endpoints included response rates, overall survival (OS), pharmacokinetics (PK), and biomarkers for cediranib.

RESULTS

Cediranib treatment resulted in an estimated 3-month PFS rate of 77% (60%, 99%). Median PFS was 5.3 (3.5,9.7) months, stable disease was seen in 5/17 patients (29%), and median OS was 11.7 (7.5-13.6) months. Grade 3 toxicities included hypertension (29%), hyponatremia (29%), and hyperbilirubinemia (18%). Cediranib PK were comparable to those seen in cancer patients with normal hepatic function. Plasma levels of VEGF and PlGF increased and sVEGFR1, sVEGFR2, and Ang-2 decreased after cediranib treatment. PFS was inversely correlated with baseline levels of VEGF, sVEGFR2, and bFGF and with on-treatment levels of bFGF and IGF-1, and directly associated with on-treatment levels of IFN-γ. OS was inversely correlated with baseline levels of sVEGFR1, Ang-2, TNF-α, CAIX, and CD34(+)CD133(+)CD45(dim) circulating progenitor cells and on-treatment levels of sVEGFR2.

CONCLUSIONS

Despite the limitations of primary endpoint selection, cediranib at 30-mg daily showed a high incidence of toxicity and preliminary evidence of antitumor activity in advanced HCC. Hepatic dysfunction did not seem to affect the steady-state PK of cediranib. Exploratory studies suggested proangiogenic and inflammatory factors as potential biomarkers of anti-VEGF therapy in HCC.

The potential role of aerobic exercise to modulate cardiotoxicity of molecularly targeted cancer therapeutics

Molecularly targeted therapeutics (MTT) are the future of cancer systemic therapy. They have already moved from palliative therapy for advanced solid malignancies into the setting of curative-intent treatment for early-stage disease. Cardiotoxicity is a frequent and potentially serious adverse complication of some targeted therapies, leading to a broad range of potentially life-threatening complications, therapy discontinuation, and poor quality of life. Low-cost pleiotropic interventions are therefore urgently required to effectively prevent and/or treat MTT-induced cardiotoxicity. Aerobic exercise therapy has the unique capacity to modulate, without toxicity, multiple gene expression pathways in several organ systems, including a plethora of cardiac-specific molecular and cell-signaling pathways implicated in MTT-induced cardiac toxicity. In this review, we examine the molecular signaling of antiangiogenic and HER2-directed therapies that may underpin cardiac toxicity and the hypothesized molecular mechanisms underlying the cardioprotective properties of aerobic exercise. It is hoped that this knowledge can be used to maximize the benefits of small molecule inhibitors, while minimizing cardiac damage in patients with solid malignancies.

New agents on the horizon in hepatocellular carcinoma

Despite the successful approval and extensive application of sorafenib, the prognosis for patients with advanced hepatocellular carcinoma (HCC) remains poor. Fortunately, there have been renewed and continued interests and active research in developing other molecularly targeted agents in HCC during the past few years. While there is early evidence of antitumor activity of several agents in phase I/II studies, phase III efforts with a few targeted agents have failed, highlighting the challenges of new drug development in HCC. This review summarizes the current status of other molecularly targeted agents under development in advanced HCC.

Vascular endothelial growth factor (VEGF) receptors: drugs and new inhibitors

The recent launch onto the market of five VEGFR inhibitors indicates the therapeutic value of these agents and the importance of the research in the field of angiogenesis inhibitors for future oncologic therapy. In this Perspective we briefly report the inhibitors that are in clinical use, while we dedicate two wider sections to the compounds that are in clinical trials and to the new derivatives appearing in the literature. We especially consider the medicinal chemistry aspect of the topic and report the structure-activity relationship studies and the binding mode of some inhibitors as well as the biological data of the compounds discovered in the past 5 years.

Antiangiogenic therapy for glioma

Currently, antiangiogenic agents are routinely used for the treatment of patients with glioma. However, despite advances in pharmacological and surgical therapy, glioma remains an incurable disease. Indeed, the formation of an abnormal tumor vasculature and the invasion of glioma cells along neuronal tracts are proposed to comprise the major factors that are attributed to the therapeutic resistance of these tumors. The development of curative therapeutic modalities for the treatment of glioma requires further investigation of the molecular mechanisms regulating angiogenesis and invasion. In this review, we discuss the molecular characteristics of angiogenesis and invasion in human malignant glioma, we present several available drugs that are used or can potentially be utilized for the inhibition of angiogenesis in glioma, and we focus our attention on the key mediators of the molecular mechanisms underlying the resistance of glioma to antiangiogenic therapy.