Chemotherapy for advanced hepatocellular carcinoma in the sorafenib age

Emerging Role of Circular RNAs in Hepatocellular Carcinoma Immunotherapy

Hepatocellular carcinoma (HCC) is a highly fatal malignancy with limited therapeutic options and high recurrence rates. Recently, immunotherapeutic agents such as immune checkpoint inhibitors (ICIs) have emerged as a new paradigm shift in oncology. ICIs, such as programmed cell death protein 1 (PD-1) inhibitors, have provided a new source of hope for patients with advanced HCC. Yet, the eligibility criteria of HCC patients for ICIs are still a missing piece in the puzzle. Circular RNAs (circRNAs) have recently emerged as a new class of non-coding RNAs that play a fundamental role in cancer pathogenesis. Structurally, circRNAs are resistant to exonucleolytic degradation and have a longer half-life than their linear counterparts. Functionally, circRNAs possess the capability to influence various facets of the tumor microenvironment, especially at the HCC tumor-immune synapse. Notably, circRNAs have been observed to control the expression of immune checkpoint molecules within tumor cells, potentially impeding the therapeutic effectiveness of ICIs. Therefore, this renders them potential cancer-immune biomarkers for diagnosis, prognosis, and therapeutic regimen determinants. In this review, the authors shed light on the structure and functional roles of circRNAs and, most importantly, highlight the promising roles of circRNAs in HCC immunomodulation and their potential as promising biomarkers and immunotherapeutic regimen determinants.

Mitochondria-Targeting-Based of Paclitaxel-Loaded Triphenylphosphine-Pluronic F127-Hyaluronic Acid Nanomicelles in Multi-Drug Resistant Hepatocellular Carcinoma

Background: In this study a new novel nanomicelle (TPH) sco-loaded with triphenylphosphine (TPP)-Pluronic F127-hyaluronic acid (HA) and Paclitaxel (PTX) has been designed to treat multidrug resistant hepatocellular carcinoma (HCC). Methods: TPH was initially synthesized by ester bond formation with mitochondria-targeting TPP agent and TPH nanomicelles loaded with PTX (TPH/PTX) had outstanding physical characteristics in human multi drug-resistant HCC cell line Bel7402/5-FU. Cytotoxicity and hemocompatibility assessments, nanomicelle cellular absorption and mitochondrial targeting, and in vivo xenograft imaging was used to evaluate that the nonemicells delivered into target cell and components. Results: The results of fluorescence test showed that TPP could promote the fusion of nanomicells to human multi drugresistant HCC cell line Bel7402/5-FU, and targeted the mitochondria, and also improved the targeting and retention of drugs in liver tumors. The results of cell efficacy showed that TPH/PTX induced a strong apoptosis effect, which could significantly reduce the mitochondrial membrane Zeta potential, increase the level of intracellular ROS and the release of Caspase-3, significantly enhanced the pro-apoptotic protein (Bcl-2), decrease the expression level of anti-apoptotic protein (Bax). Conclusion: TPH/PTX has a promising mitochondrial targeting function, and can enhance the effect of drugs on promoting apoptosis of drug resistant HCC cells.

Hepatocellular Carcinoma Immunotherapy

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and the third leading cause of cancer-related death worldwide. Single-agent anti-PD-1 immune checkpoint inhibitors (ICIs) demonstrated promising efficacy in early-phase trials, a finding that was not confirmed in phase III studies. The combination of atezolizumab (an anti-PD-L1 ICI) with bevacizumab (an anti-VEGF antibody) was approved as first-line therapy in 2020, however, with significant improvement in response rate, progression-free survival, and overall survival in comparison with the previous standard of care, sorafenib. Numerous ongoing clinical trials are assessing ICIs in combination with each other or with targeted agents, and also in earlier stages with local therapies. This review summarizes the latest concepts in the use of ICIs for the management of HCC. Expected final online publication date for the Annual Review of Medicine, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Application of self-assembly peptides targeting the mitochondria as a novel treatment for sorafenib-resistant hepatocellular carcinoma cells

Currently, there is no appropriate treatment option for patients with sorafenib-resistant hepatocellular carcinoma (HCC). Meanwhile, pronounced anticancer activities of newly-developed mitochondria-accumulating self-assembly peptides (Mito-FF) have been demonstrated. This study intended to determine the anticancer effects of Mito-FF against sorafenib-resistant Huh7 (Huh7-R) cells. Compared to sorafenib, Mito-FF led to the generation of relatively higher amounts of mitochondrial reactive oxygen species (ROS) as well as the greater reduction in the expression of antioxidant enzymes (P < 0.05). Mito-FF was found to significantly promote cell apoptosis while inhibiting cell proliferation of Huh7-R cells. Mito-FF also reduces the expression of antioxidant enzymes while significantly increasing mitochondrial ROS in Huh7-R cells. The pro-apoptotic effect of Mito-FFs for Huh7-R cells is possibly caused by their up-regulation of mitochondrial ROS, which is caused by the destruction of the mitochondria of HCC cells.

Circulating biomarkers for early detection of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is estimated to be the fourth leading cause of cancer-related deaths worldwide. HCC patients face a dismal prognosis because symptoms usually appear in an advanced stage of disease. The detection of early stage HCC allows for curative surgical treatment and therefore saves lives. Specific non-invasive or diagnostic markers for HCC may represent a valuable tool for detecting these tumors at an early stage. The clinically most established serological biomarker alpha-fetoprotein shows only limited diagnostic performance, however novel candidate biomarkers and biomarker panels for detecting HCC at early stages of development are being studied. In this review we will discuss the findings of these studies.

The role of microRNA in the resistance to treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the second most common cause of cancer-related death with a limited efficacy of treatment for intermediate and advanced stages of the disease. Several therapeutic approaches such as trans-arterial chemoembolization (TACE) with anthracyclines, cisplatin and multikinase inhibitor sorafenib have been appealing choices of treatments yet failed to reach a satisfactory outcome mainly due to the numerous mechanisms that influence patient's response. MicroRNAs (miRNAs) are key regulators of many intracellular processes related to drug resistance. This phenomenon has been linked to the modulation of several complex pathways, ranging from the loss of ability of drug accumulation, protective mechanism of autophagy, adaptive mechanism of cancer cells towards the drugs-induced environment, decrease DNA damage and suppression of downstream events that transduce its signal into apoptosis. We summarize the recent findings on the involvement of miRNAs in various drug resistance-related mechanisms in the development of resistance to anthracyclines, cisplatin and sorafenib therapies. Furthermore, we describe the possible application of miRNAs as circulating biomarkers predicting therapy response in HCC. Thus, the undeniable potential and paramount role of miRNA in drug resistance may eventually lead to improved clinical strategies and outcomes for HCC patients.

Cytostatic and Anti-tumor Potential of Ajwa Date Pulp against Human Hepatocellular Carcinoma HepG2 Cells

Ajwa dates (Phoenix dactylifera L.) are used by traditional therapeutic practitioners for several health benefits but most remain to be scientifically validated. In this study, we evaluated the apoptosis-inducing effect of ethanolic extract of Ajwa date pulp (ADP) on human hepatocellular carcinoma (HCC) HepG2 cells. High performance liquid chromatography analysis revealed the presence of polysaccharide β-D-glucan in ADP extract. Treated HCC cells revealed morphological characteristics of apoptosis under phase contrast microscopy. MTT assay demonstrated significant (p < 0.05) dose- and time-dependent inhibition of HCC cell growth. HCC cells were found to be in late apoptotic stage on treatment with higher doses of ADP extract as depicted by acridine orange/ethidium bromide and Annexin V-FITC/PI double stain. Importantly, ADP extract increased the reactive oxygen species level and decreased the mitochondrial membrane potential in treated HCC cells. Flow cytometry analysis demonstrated that ADP extract induced elevation of S and G2/M phases of cell cycle. Moreover, ADP extract induced apoptosis in HCC cells independent of tumor suppressor genes viz. CHEK2, ATM and TP53. Interestingly, ADP extract did not display any significant effect on normal cell line Vero. This study provides validation that ADP extract can be considered as a safe and natural potential drug candidate against human liver cancer.

Synthesis and biological evaluation of α-santonin derivatives as anti-hepatoma agents

A series of α-santonin-derived compounds as potentially anti-hepatoma agents were designed and synthesized in an effort to find novel therapeutic agents. Among them, derivative 5h was more potent than the positive control 5-fluorouracil (5-Fu) on HepG-2, QGY-7703 and SMMC-7721 with IC₅₀ values of 7.51, 3.06 and 4.08 μM, respectively. The structure-activity relationships (SARs) of these derivatives were discussed. In addition, flow cytometry and western blot assay revealed that the derivatives induced hepatoma cells apoptosis by facilitating apoptosis-related proteins expressions. Our findings suggested that these α-santonin-derived analogues hold promise as chemotherapeutic agents for the treatment of human hepatocellular cancer.

Design, synthesis and biological evaluation of new pyrrolidine carboxamide analogues as potential chemotherapeutic agents for hepatocellular carcinoma

The successful targeting of different malignancies by OSU-2S, encouraged us to design and synthesize a novel series of pyrrolidine aryl carboxamide derivatives. In this context, we found that, the amide nature and tether length were found to be key determinant elements for the anticancer activity of these new and rigid analogues of OSU-2S. The most effective analogues induced apoptosis in cancer cells by a similar mechanism to that of OSU-2S, possibly via the activation of PKCδ in addition to their ability to induce cell cycle arrest and inhibition of cancer cell migration. Compound 10m, possesses anticancer potency comparable to that of OSU-2S when tested against cancer cell lines under study, and was found to be safer on normal cells. Furthermore, compound 10m, was found to be about 2-folds more potent than the anticancer drug Sorafenib in hepatocellular carcinoma (HCC). The newly developed compounds represent a therapeutically promising approach for the treatment of HCC.

Eupafolin Exhibits Potent Anti-Angiogenic and Antitumor Activity in Hepatocellular Carcinoma

Eupafolin is a flavonoid extracted from the common sage herb which has been used in China as traditional medicine. Previous studies had reported that eupafolin had antioxidative, anti-inflammatory and antitumor effects. However, the function and the mechanism of eupafolin to exert its antitumor activity, especially its effect on tumor angiogenesis, have not been elucidated. Herein, we showed that eupafolin significantly inhibited vascular endothelial growth factor (VEGF)-induced cell proliferation, migration and tube formation of human umbilical vascular endothelial cells (HUVECs) in a dose-dependent manner. Meanwhile, the new blood microvessels induced by VEGF in the matrigel plug were also substantially suppressed by eupafolin. The results of HCC xenograft experiments demonstrated eupafolin remarkably inhibited tumor growth and tumor angiogenesis in vivo, suggesting the antitumor activity exerted by eupafolin was closely correlated with its potency on tumor angiogenesis. Mechanism investigations revealed that eupafolin significantly blocked VEGF-induced activation of VEGFR2 in HUVEC cells as well as its downstream signaling pathway. In addition to the effect on endothelial cells, through inhibiting Akt activity in tumor cells, VEGF secretion in HepG2 was dramatically decreased after eupafolin treatment. Our study was the first to report the activity of eupafolin against tumor angiogenesis as well as the underlying mechanism by which eupafolin to exert its anti-angiogenic activity.

Liposome-mediated RNA interference delivery against Erk1 and Erk2 does not equally promote chemosensitivity in human hepatocellular carcinoma cell line HepG2

BACKGROUND

Extracellular signal-regulated kinase (Erk)1 and Erk2 are central mediators of mitogen-activated protein kinase signaling pathway, which plays a key role in proliferation and chemoresistance of cancer cells. However, the effect of Erk1 and Erk2 in these processes may not be the same. The aim of this study was to investigate differential effect of Erk1 and Erk2 down-regulation on chemoresistance in human hepatocellular carcinoma (HCC) cells. Expression level and relative expression analysis in HepG2 cells were performed using RT-PCR and qRT-PCR, respectively. Phosphorylated-Erk1/2 and apoptosis analysis was performed by flow-cytometry (FCM) technique.

RESULTS

The results showed a higher expression level of Erk2 relative to Erk1 in HepG2 cells (P < 0.01). A significant decrease in phosphorylated-Erk1/2 and a compensational response was observed after Erk1 and/or Erk2 silencing using specific small interfering ribonucleic acids (siRNAs) (P < 0.01). Furthermore, 5-fluorouracil (5-FU) chemotherapy following siRNA-mediated knockdown lead to a significant enhancement of chemosensitivity with a higher rate of early apoptosis in Erk2 silencing relative to that of Erk1) + 9%, P < 0.01). 5-FU treatment after dual knockdown of Erk1/2 showed higher rate of early apoptosis relative to single Erk1 silencing (+9.25%, P < 0.01) and also higher rate of late apoptosis compared to single Erk1 and Erk2 silencing (+4.96% and +4.66%, P < 0.01).

CONCLUSION

Our data show that liposomal siRNA-mediated down-regulation of Erk1/2 can lead to potent chemosensitizing effects in HepG2 cells. Moreover, a higher chemosensitivity following Erk2 down-regulation than Erk1 down-regulation may be associated with the higher expression of Erk2 in human HCC.

Phase I study of nintedanib in Japanese patients with advanced hepatocellular carcinoma and liver impairment

This phase I, dose-escalation study evaluated the safety, preliminary efficacy and pharmacokinetics of nintedanib, a triple angiokinase inhibitor, in Japanese patients with advanced hepatocellular carcinoma and mild/moderate liver impairment. Thirty patients with unresectable hepatocellular carcinoma were enrolled to groups, depending on whether liver impairment was mild (group I, aspartate aminotransferase and alanine aminotransferase ≤2× upper limit of normal and Child-Pugh score 5 [n = 14] or 6 [n = 2]) or moderate (group II, Child-Pugh score 5-6 and aspartate aminotransferase or alanine aminotransferase >2× to ≤5× upper limit of normal [n = 7] or Child-Pugh score 7 [n = 7]); 22 patients had prior sorafenib treatment. Nintedanib was given twice daily in 28-day cycles until disease progression or unacceptable adverse events, starting at 150 mg (group I) or 100 mg (group II) and escalating to 200 mg. The primary objective was to define the maximum tolerated dose based on occurrence of dose-limiting toxicities during cycle 1 (grade ≥3 non-hematological and grade 4 hematological adverse events). No dose-limiting toxicities were reported during cycle 1 and the maximum tolerated dose for both groups was 200 mg twice daily. The most frequent adverse events were gastrointestinal (diarrhea, nausea, vomiting, and decreased appetite). No patients discontinued nintedanib due to adverse events; 31% of group I and 21% of group II had dose reductions. Median time to progression was 2.8 months (95% confidence interval, 1.05-5.52) for group I and 3.2 months (95% confidence interval, 0.95-6.70) for group II. Nintedanib showed a manageable safety profile and efficacy signals, including in patients previously treated with sorafenib. Clinical trial registration NCT01594125; 1199.120 (ClinicalTrials.gov).

Anticancer effect of 20(S)-ginsenoside Rh2 on HepG2 liver carcinoma cells: Activating GSK-3β and degrading β-catenin

20(S)-ginsenoside Rh2 [(S)Rh2] possesses potential to prevent cancer in vitro as well as in vivo, but the underlying mechanism is still unknown. First, we infected HepG2 cells with lentivirus which carries β‑catenin. We detected the pharmacological effects of (S)Rh2 on HepG2 and HepG2‑β‑catenin cells and found that the IC50 of (S)Rh2 exposure on HepG2-β-catenin cells was higher than HepG2 cells. Flow cytometry (FCM) indicated that (S)Rh2 could be arrested in G0/G1 phase and induce early apoptosis in HepG2 and HepG2‑β‑catenin cells. Second, ELISA kit was used to check the activity of glycogen synthase kinase‑3β (GSK‑3β), which was upregulated by (S)Rh2. GSK‑3β inhibitor BIO, was used to verify that (S)Rh2 activated GSK‑3β. PCR and western blotting results indicated that (S)Rh2 could degrade the expression of β‑catenin, which combined with TCF in the nucleus and activate transcription of Wnt target genes, such as Bax, Bcl‑2, cyclin D1, MMP3, which were checked by chromatin immunoprecipitation (ChIP), PCR and western blotting. The results showed that the expression of Bax mRNA and proteins increased, while the cyclin D1, Bcl‑2, MMP3 mRNA and proteins were downregulated in HepG2 and HepG2‑β‑catenin cells which was induced by (S)Rh2. By contrast, with the HepG2-β-catenin + (S)Rh2 group, the expression of other mRNA and proteins in HepG2 + (S)Rh2 group changed significantly. In vivo, experiments were performed using a nude mouse xenograft model to investigate the (S)Rh2 effect. So these results suggested that (S)Rh2 could suppress proliferation, promote apoptosis and inhibit metastasis of HepG2, decrease weight of tumor by downregulating β‑catenin through activating GSK‑3β and the pharmacological effect of (S)Rh2 on HepG2 cells might be weakened by overexpression of β‑catenin.

Inhibition of nuclear factor κB transcription activity drives a synergistic effect of cisplatin and oridonin on HepG2 human hepatocellular carcinoma cells

Activation of nuclear factor κB (NF-κB) by cisplatin and other chemotherapeutics is responsible, at least in part, for the development of drug resistance in the treatment of hepatocellular carcinoma. Therefore, a combination of chemotherapeutics with NF-κB inhibitors could overcome resistance of cancer cells. Oridonin is a diterpenoid isolated from Rabdosia rubescens that can block the NF-κB signaling cascades. In this study, we investigated the synergistic effect of oridonin and cisplatin on human hepatocellular carcinoma HepG2 cells. Cell apoptosis and mitochondrial membrane potential loss were examined using Hoechst 33258 and rhodamine-123 staining, followed by flow cytometry, respectively. The expression of apoptosis-related proteins and NF-κB subunits was detected by real-time PCR and western blot. The activity of caspase 3 and 9 was measured using the Caspase Activity Kit. Electrophoretic mobility shift assay and the enzyme-linked immunosorbent assay-based kit were used to assess the DNA-binding activity of NF-κB. We found a synergistic antitumor effect between cisplatin and oridonin on HepG2 cells both in vitro and in vivo. In addition, the combination of cisplatin and oridonin synergistically induces apoptosis and regulates the expression and activity of several key apoptosis-related proteins. Furthermore, the combination treatment not only downregulates nuclear translocation of p50 and p65, but more significantly, decreases the transcription activity of all NF-κB subunits to a greater degree than either agent alone. Our results suggest that the synergistic effect between both agents is likely to be driven by the inhibition of transcription activity of NF-κB and the resulting increased apoptosis.

Chest wall hernia induced by high intensity focused ultrasound treatment of unresectable massive hepatocellular carcinoma: A case report

In the present study, a case of unresectable massive hepatocellular carcinoma (HCC) treated with high intensity focused ultrasound (HIFU) alone is reported. Although the treatment induced chest wall hernia, its efficacy in treating the HCC was demonstrated. The medical records of a patient with an unresectable massive tumor that was effectively treated with serial HIFU ablation were retrospectively studied. Chest wall hernia was detected as a complication of the HIFU treatment, which has not been reported thus far in the literature. The patient has survived for 44 months since the first diagnosis in September 2010. Treatment resulted in partial remission of the tumor, pain relief, decreased levels of alpha-fetoprotein and chest wall hernia, as a complication. Therefore, HIFU may be an effective approach for the treatment of unresectable HCC, although it may occasionally cause complications.

Hepatocellular carcinoma: Where are we?

Hepatocellular carcinoma (HCC) is the second cause of death due to malignancy in the world, following lung cancer. The geographic distribution of this disease accompanies its principal risk factors: Chronic hepatitis B virus and hepatitis C virus infection, alcoholism, aflatoxin B1 intoxication, liver cirrhosis, and some genetic attributes. Recently, type II diabetes has been shown to be a risk factor for HCC together with obesity and metabolic syndrome. Although the risk factors are quite well known and it is possible to diagnose HCC when the tumor is less than 1 cm diameter, it remains elusive at the beginning and treatment is often unsuccessful. Liver transplantation is thus far considered the best treatment for HCC as it cures HCC and the underlying liver disease. Using the Milan criteria, overall survival after liver transplantation for HCC is about 70% after 5 years. Many attempts have been made to go beyond the Milan Criteria and according to recent works reasonably good results have been achieved by using a histochemical marker such as cytokeratine 19 and the so-called "up to seven criteria" to divide patients into categories according to their risk of relapse. In addition to liver transplantation other therapies have been proposed such as resection, tumor ablation by different means, embolization and chemotherapy. An important step in the treatment of advanced HCC has been the introduction of sorafenib, the first oral, systemic drug that has provided significant improvement in survival. Treatment of HCC patients must be multidisciplinary and by using the different approaches discussed in this review it is possible to offer prolonged survival and quite good and sometimes even excellent quality of life to many patients.

Co-delivery of platinum drug and siNotch1 with micelleplex for enhanced hepatocellular carcinoma therapy

As part of HCC tumor cellularity, cancer stem cells (CSCs) are considered a major obstacle to eradicate hepatocellular carcinoma (HCC), which is the third most common cause of cancer-related death worldwide, and the accumulation of chemotherapeutic drug-resistant CSCs invariably accounts for poor prognosis and HCC relapse. In the present study, we explored the efficacy of co-delivery of platinum drug and siRNA targeting Notch1 to treat CSCs-harboring HCC. To overcome the challenging obstacles of platinum drug and siRNA in the systemic administration, we developed a micellar nanoparticle (MNP) to deliver platinum(IV) prodrug and siNotch1, hereafter referred to as (Pt(IV))MNP/siNotch1. We demonstrated that (Pt(IV))MNP/siNotch1 was able to efficiently deliver two drugs into both non-CSCs and CSCs of SMMC7721, a HCC cell line. We further found that siRNA-mediated inhibition of Notch1 suppression can increase the sensitivity of HCC cells to platinum drugs and decrease the percentage of HCC CSCs, and consequently resulting in enhanced proliferation inhibition and apoptosis induction in HCC cells in vitro. Moreover, our results indicated that the combined drug delivery system can remarkably augment drug enrichment in tumor tissues, substantially suppressing the tumor growth while avoiding the accumulation of CSCs in a synergistic manner in the SMMC7721 xenograft model.

Inhibition of protein kinase C by isojacareubin suppresses hepatocellular carcinoma metastasis and induces apoptosis in vitro and in vivo

Targeted inhibition of protein kinase C (PKC) inhibits hepatocellular carcinoma (HCC) proliferation and metastasis. We previously reported the cytotoxicity of a series of synthetic phenyl-substituted polyoxygenated xanthone derivatives against human HCC. In the current study, the most potent natural product, isojacareubin (ISJ), was synthesized, and its cellular-level antihepatoma activities were evaluated. ISJ significantly inhibited cell proliferation and was highly selective for HCC cells in comparison to nonmalignant QSG-7701 hepatocytes. Moreover, ISJ exhibited pro-apoptotic effects on HepG2 hepatoma cells, as well as impaired HepG2 cell migration and invasion. Furthermore, ISJ was a potent inhibitor of PKC, with differential actions against various PKC isotypes. ISJ selectively inhibited the expression of aPKC (PKCζ) in the cytosol and the translocation of cytosolic PKCζ to membrane site. ISJ also directly interacted with cPKC (PKCα) and nPKC (PKCδ, PKCε and PKCμ) and thereby inhibited the early response of major MAPK phosphorylation and the late response of HCC cell invasion and proliferation. In a hepatoma xenograft model, ISJ pretreatment resulted in significant antihepatoma activity in vivo. These findings identify ISJ as a promising lead compound for the development of new antihepatoma agents and may guide the search for additional selective PKC inhibitors.

Advanced hepatocellular carcinoma and sorafenib: Diagnosis, indications, clinical and radiological follow-up

Advanced stage hepatocellular carcinoma (HCC) is a category of disease defined by radiological, clinical and hepatic function parameters, comprehending a wide range of patients with different general conditions. The main therapeutic option is represented by sorafenib treatment, a multi-kinase inhibitor with anti-proliferative and anti-angiogenic effect. Trans-arterial Radio Embolization also represents a promising new approach to intermediate/advanced HCC. Post-marketing clinical studies showed that only a portion of patients actually benefits from sorafenib treatment, and an even smaller percentage of patients treated shows partial/complete response on follow-up examinations, up against relevant costs and an incidence of drug related adverse effects. Although the treatment with sorafenib has shown a significant increase in mean overall survival in different studies, only a part of patients actually shows real benefits, while the incidence of drug related significant adverse effects and the economic costs are relatively high. Moreover, only a small percentage of patients also shows a response in terms of lesion dimensions reduction. Being able to properly differentiate patients who are responding to the therapy from non-responders as early as possible is then still difficult and could be a pivotal challenge for the future; in fact it could spare several patients a therapy often difficult to bear, directing them to other second line treatments (many of which are at the moment still under investigation). For this reason, some supplemental criteria to be added to the standard modified Response Evaluation Criteria in Solid Tumors evaluation are being searched for. In particular, finding some parameters (cellular density, perfusion grade and enhancement rate) able to predict the sensitivity of the lesions to anti-angiogenic agents could help in stratifying patients in terms of treatment responsiveness before the beginning of the therapy itself, or in the first weeks of sorafenib treatment. This would bring a strongly desirable help in clinical managements of these patients.

Systemic therapy of hepatocellular carcinoma: current and promising

Treatment of advanced hepatocellular carcinoma (HCC) remains challenging, particularly with the limited systemic therapy options. Sorafenib remains the only approved, targeted molecule for the treatment of advanced HCC. Although a survival benefit was demonstrated with sorafenib, it remains only true in the population of patients with Child-Turcotte-Pugh class A disease. Sorafenib also has distinct side effects that require close monitoring. Newer tyrosine kinase inhibitors and angiogenic inhibitors have been evaluated with disappointing results, particularly in phase III trials. Herein we review the pertinent trials for targeted therapy in HCC to date.

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.

Downregulation of stanniocalcin 1 is responsible for sorafenib-induced cardiotoxicity

Sorafenib is associated with adverse cardiac effects, including left ventricular dysfunction. However, the precise mechanism remains unclear. Here, we aimed to establish the genes responsible for this cardiotoxicity using zebrafish and human cardiomyocytes. Fluorescent cardiac imaging using pigmentless zebrafish with green fluorescent protein hearts revealed that the ventricular dimensions of the longitudinal axis with sorafenib were significantly shorter than those of the control group. Transcriptome analysis of their hearts revealed that stanniocalcin 1 (stc1) was downregulated by sorafenib. stc1 knockdown in zebrafish revealed that reduction of stc1 decreased the longitudinal dimensions of zebrafish ventricles, similar to that which occurs during sorafenib treatment. STC1 downregulation and cytotoxicity were also seen in human cardiomyocytes exposed to sorafenib. To clarify the molecular function of stc1 in sorafenib-induced cardiotoxicity, we focused on oxidative stress in cardiomyocytes treated with sorafenib. Reactive oxygen species (ROS) production significantly increased in both species of human cardiomyocytes and zebrafish exposed to sorafenib and STC1 knockdown compared with the controls. Finally, we found that forced expression of stc1 normalized impairment, decreasing the longitudinal dimensions in zebrafish treated with sorafenib. Our study demonstrated that STC1 plays a protective role against ventricular dysfunction and ROS overproduction, which are induced by sorafenib treatment. We discovered for the first time that STC1 downregulation is responsible for sorafenib-induced cardiotoxicity through activated ROS generation.