Role of regorafenib as second-line therapy and landscape of investigational treatment options in advanced hepatocellular carcinoma

Anti-proliferative, -migratory and -clonogenic effects of long-lasting nitric oxide release in HepG2 cells

Nitric oxide (NO) holds promise as a cytotoxic agent against tumors, but its gaseous nature and short half-life hinder direct administration to tumor tissues. Herein, we present novel 6,9-disubstituted purine derivatives designed to ensure sustained NO release, followed by study of their significant anti-proliferative, anti-migratory, and anti-clonogenic effects on HepG2 cell lines, highlighting NO release as a potent effector for treating hepatocellular carcinoma.

ESM1 Interacts with c-Met to Promote Gastric Cancer Peritoneal Metastasis by Inducing Angiogenesis

The peritoneum is the most common metastatic site of advanced gastric cancer and is associated with extremely poor prognosis. Endothelial-specific molecule 1 (ESM1) was found to be significantly associated with gastric cancer peritoneal metastasis (GCPM); however, the biological functions and molecular mechanisms of ESM1 in regulating GCPM remain unclear. Herein, we demonstrated that ESM1 expression was significantly upregulated in gastric cancer tissues and positively correlated with platelet endothelial cell adhesion molecule-1 (CD31) levels. Moreover, clinical validation, in in vitro and in vivo experiments, confirmed that ESM1 promoted gastric cancer angiogenesis, eventually promoting gastric cancer peritoneal metastasis. Mechanistically, ESM1 promoted tumor angiogenesis by binding to c-Met on the vascular endothelial cell membrane. In addition, our results confirmed that ESM1 upregulated VEGFA, HIF1α, and MMP9 expression and induced angiogenesis by activating the MAPK/ERK pathway. In conclusion, our findings identified the role of ESM1 in gastric cancer angiogenesis and GCPM, thus providing insights into the diagnosis and treatment of advanced gastric cancer.

Regorafenib induces damage-associated molecular patterns, cancer cell death and immune modulatory effects in a murine triple negative breast cancer model

Damage associated molecular patterns (DAMPs), including calreticulin (CRT) exposure, high-mobility group box 1 protein (HMGB1) elevation, and ATP release, characterize immunogenic cell death (ICD) and may play a role in cancer immunotherapy. Triple negative breast cancer (TNBC) is an immunogenic subtype of breast cancer with higher lymphocyte infiltration. Here, we found that regorafenib, a multi-target angiokinase inhibitor previously known to suppress STAT3 signaling, induced DAMPs and cell death in TNBC cells. Regorafenib induced the expression of HMGB1 and CRT, and the release of ATP. Regorafenib-induced HMGB1 and CRT were attenuated following STAT3 overexpression. In a 4T1 syngeneic murine model, regorafenib treatment increased HMGB1 and CRT expression in xenografts, and effectively suppressed 4T1 tumor growth. Immunohistochemical staining revealed increased CD4⁺ and CD8⁺ tumor-infiltrating T cells in 4T1 xenografts following regorafenib treatment. Regorafenib treatment or programmed death-1 (PD-1) blockade using anti-PD-1 monoclonal antibody reduced lung metastasis of 4T1 cells in immunocompetent mice. While regorafenib increases the proportion of MHC II high expression on dendritic cells in mice with smaller tumors, the combination of regorafenib and PD-1 blockade did not show a synergistic effect on anti-tumor activity. These results suggest that regorafenib induces ICD and suppresses tumor progression in TNBC. It should be carefully evaluated when developing a combination therapy with an anti-PD-1 antibody and a STAT3 inhibitor.

The Dynamic Role of NK Cells in Liver Cancers: Role in HCC and HBV Associated HCC and Its Therapeutic Implications

Hepatocellular carcinoma (HCC) remains an important complication of chronic liver disease, especially when cirrhosis occurs. Existing treatment strategies include surgery, loco-regional techniques, and chemotherapy. Natural killer cells are distinctive cytotoxic lymphocytes that play a vital role in fighting tumors and infections. As an important constituent of the innate immune system against cancer, phenotypic and functional deviations of NK cells have been demonstrated in HCC patients who also exhibit perturbation of the NK-activating receptor/ligand axis. The rate of recurrence of tumor-infiltrating and circulating NK cells are positively associated with survival benefits in HCC and have prognostic significance, suggesting that NK cell dysfunction is closely related to HCC progression. NK cells are the first-line effector cells of viral hepatitis and play a significant role by directly clearing virus-infected cells or by activating antigen-specific T cells by producing IFN-γ. In addition, chimeric antigen receptor (CAR) engineered NK cells suggest an exclusive opportunity to produce CAR-NKs with several specificities with fewer side effects. In the present review, we comprehensively discuss the innate immune landscape of the liver, particularly NK cells, and the impact of tumor immune microenvironment (TIME) on the function of NK cells and the biological function of HCC. Furthermore, the role of NK cells in HCC and HBV-induced HCC has also been comprehensively elaborated. We also elaborate on available NK cell-based immunotherapeutic approaches in HCC treatment and summarize current advancements in the treatment of HCC. This review will facilitate researchers to understand the importance of the innate immune landscape of NK cells and lead to devising innovative immunotherapeutic strategies for the systematic treatment of HCC.

Strategic enhancement of immune checkpoint inhibition in refractory Colorectal Cancer: Trends and future prospective

Colorectal cancer (CRC), known as a frequently fatal disease, ranking as the third most common malignancy, is the second leading cause of cancer related mortality worldwide. Metastases are common in CRC patients which account for approximately 25% of the patients at diagnosis, 50% of patients during treatment which is associated closely with CRC mortality. Conventional therapies such as surgery, chemotherapy, and radiotherapy are standards of care for the treatment of CRC patients. However, primary tumor recurrence and secondary disease in patients receiving standard of care treatment modalities occur in 50% of patients so that new treatment modalities are needed. Immune checkpoint inhibition (ICI) has transformed the management of patients suffered from metastatic CRC (mCRC) with mismatch repair deficiency (dMMR) and microsatellite instability (MSI) -high (MSI-H) while manifests ineffectiveness in preserved mismatch repair (pMMR) or microsatellite stable (MSS) "cold" tumors which makes up the majority (95%) of mCRC. In this review, we mainly lay emphasis on the development of combinations in therapy strategies with ICIs with other immune based treatment approaches to increase the intra-tumoral immune response and render tumors 'immune-reactive', thereby increasing the efficacy of tumor immunotherapy.

Advances in pharmacotherapeutics for hepatocellular carcinoma

INTRODUCTION

Although hepatocellular carcinoma (HCC) is the most frequent primary liver cancer, there are limited therapeutic options for the advanced stages. Sorafenib was the first tyrosine-kinase inhibitor (TKI) approved for unresectable HCC and remained the only effective choice for a decade. The horizon of systemic treatments drastically expanded in the latest years, opening new interesting possibilities.

AREAS COVERED

In this manuscript, the authors have analysed the recent advances in pharmacotherapy for HCC, discussing their mechanisms of action, the clinical efficacy and the safety profile of currently available first, second-and third-line treatments. The authors have also analysed the role of immune system modulators, in particular immune checkpoints inhibitors (ICIs), based on the limited data published so far.

EXPERT OPINION

The emergence of new targeted therapies, such as lenvatinib, have changed the landscape of HCC therapy. Tumor extension, differences in objective response rates and adverse events profiles should be considered to tailor the choice of the first-line agent. Sorafenib remains the most studied drug, with much real-world data available. The efficacy of second line therapies has only been proven in non-responder or sorafenib-intolerant patients. Unfortunately, studies directly comparing the second-line agents regorafenib, ramucirumab and cabozantinib are still lacking.

Uncovering Biological Factors That Regulate Hepatocellular Carcinoma Growth Using Patient-Derived Xenograft Assays

BACKGROUND AND AIMS

Several major factors limit our understanding of hepatocellular carcinoma (HCC). First, human HCCs are infrequently biopsied for diagnosis and thus are not often biologically interrogated. Second, HCC initiation and progression are strongly influenced by the cirrhotic microenvironment, and the exact contributions of intrinsic and extrinsic tumor factors are unclear. A powerful approach to examine the personalized biology of liver cancers and the influence of host tissues is with patient-derived xenograft (PDX) models. In Asia, HCCs from patients with hepatitis B virus have been efficiently converted into PDXs, but few parallel efforts from the west have been reported.

APPROACH AND RESULTS

In a large-scale analysis, we implanted 93 HCCs and 8 cholangiocarcinomas (CCAs) to systematically analyze host factors and to define an optimized platform for PDX development from both surgical and biopsy samples. NOD Scid IL-2Rγ^-/- (NSG) mice that had undergone partial hepatectomy (PHx) represented the best combination of engraftability, growth, and passageability, but overall rates were low and indicative of a unique intrinsic biology for HCCs in the United States. PDX models preserved the histology and genetic features of parental tumors, and ultimately, eight models were usable for preclinical studies. Intriguingly, HCC PDXs were differentially sensitive to regorafenib and sorafenib, and CCA PDXs were also highly sensitive to regorafenib.

CONCLUSIONS

PDX models functionalize early and advanced stage HCCs and revealed unique biological features of liver cancers from the United States.

The mechanisms of sorafenib resistance in hepatocellular carcinoma: theoretical basis and therapeutic aspects

Sorafenib is a multikinase inhibitor capable of facilitating apoptosis, mitigating angiogenesis and suppressing tumor cell proliferation. In late-stage hepatocellular carcinoma (HCC), sorafenib is currently an effective first-line therapy. Unfortunately, the development of drug resistance to sorafenib is becoming increasingly common. This study aims to identify factors contributing to resistance and ways to mitigate resistance. Recent studies have shown that epigenetics, transport processes, regulated cell death, and the tumor microenvironment are involved in the development of sorafenib resistance in HCC and subsequent HCC progression. This study summarizes discoveries achieved recently in terms of the principles of sorafenib resistance and outlines approaches suitable for improving therapeutic outcomes for HCC patients.

Treatment with a new benzimidazole derivative bearing a pyrrolidine side chain overcomes sorafenib resistance in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a major cause of cancer-related death worldwide. Currently, sorafenib is the standard first-line drug for patients with advanced HCC. However, long-term exposure to sorafenib often results in reduced sensitivity of tumour cells to the drug, leading to acquired resistance. Therefore, developing new compounds to treat sorafenib resistance is urgently needed. Although benzimidazole and its derivatives have been reported to exert antimicrobial and antitumour effects, the anti-drug resistance potential of these molecules is still unknown. In this study, we established sorafenib-resistant (SR) cell lines and an acquired sorafenib resistance xenograft model. We showed that treatment with a benzimidazole derivative bearing a pyrrolidine side chain (compound 9a) inhibited the proliferation of SR cells by blocking the phosphorylation of AKT, p70S6 and the downstream molecule RPS6. In addition, caspase 3/PARP-dependent apoptotic signals were induced in 9a-treated cells. Regarding epithelial-mesenchymal transition (EMT) activities, 9a treatment significantly suppressed the migration of SR cells. In particular, the levels of EMT-related transcription factors (snail, slug and twist) and mesenchymal markers (vimentin and N-cadherin) were downregulated. In the acquired sorafenib resistance xenograft model, compound 9a administration decreased the growth of tumours with acquired sorafenib resistance and the expression of the HCC markers α-fetoprotein, glypican 3 and survivin. In conclusion, treatment with this compound may be a novel therapeutic strategy for patients with sorafenib resistance.

Design and synthesis of novel pyridazinoquinazoline derivatives as potent VEGFR-2 inhibitors: In vitro and in vivo study

Worldwide, Hepatocellular Carcinoma (HCC) endures to be a prominent cause of cancer death. Treatment of HCC follows multiple therapies which are not entirely applicable for treatment of all patients. HCC usually arises contextual to chronic liver diseases and is often discovered at later stages which makes treatment options more complex. The present study aimed at design, synthesis & evaluation of new pyridazinoquinazoline derivatives as potential nontoxic anti-hepatocellular carcinoma (HCC) agents, through inhibition of Vascular endothelial growth factor -2 (VEGFR-2). Novel Pyridazino[3, 4, 5-de]quinazoline derivatives (2-6) were designed & synthesized. Their structures were confirmed via spectral and microanalytical data. They were tested for their in vitro VEGFR-2 inhibition & anticancer activity against human liver cancer cell line (HEPG-2). Molecular docking was investigated into VEGFR-2 site. In vivo studies of VEGRF-2 inhibition and the anti-apoptotic effect of the new compounds were determined in liver of irradiated rats. Toxicity of synthesized compounds was also assessed. The results showed that compounds 3-6 have significant antitumor activity and proved to be non-toxic. The ethoxy aniline derivative 6, exhibited the highest activity both in vitro and in vivo compared to the reference drug used, sorafenib. Compound 6 could be considered a promising nontoxic anti HCC agent and this could be partially attributed to its VEGFR-2 inhibition. Future preclinical investigation would be carried out to confirm the specific and exact mechanism of action of these derivatives especially compound 6 as an effective pharmaceutical agent after full toxicological and pharmacological assessment.

The role of natural killer cells in hepatocellular carcinoma development and treatment: A narrative review

A major obstacle for treatment of HCC is the inadequate efficacy and limitation of the available therapeutic options. Despite the recent advances in developing novel treatment options, HCC still remains one of the major causes of cancer morbidity and mortality around the world. Achieving effective treatment and eradication of HCC is a challenging task, however recent studies have shown that targeting Natural Killer cells, as major regulators of immune system, can help with the complete treatment of HCC, restoration of normal liver function and subsequently higher survival rate of HCC patients. Studies have shown that decrease in the frequency of NK cells, their dysfunction due to several factors such as dysregulation of receptors and their ligands, and imbalance of different types of inhibitory and stimulating microRNA expression is associated with higher rate of HCC progression and development, and poor survival outcome. Here in our review, we mainly focused on the importance of NK cells in HCC development and treatment.

RATIONALE 301 study: tislelizumab versus sorafenib as first-line treatment for unresectable hepatocellular carcinoma

Advanced, unresectable hepatocellular carcinoma (HCC) has a poor prognosis with median life expectancy of approximately 1 year. Overexpression of PD-L1 in tumor cells and PD-1 on tumor-infiltrating T cells has been associated with poorer prognosis, more advanced disease and higher recurrence rates in HCC. Monoclonal antibodies against PD-1 have demonstrated antitumor activity in patients with solid tumors, including HCC. Tislelizumab, an investigational, humanized IgG4 monoclonal antibody with high affinity and binding specificity for PD-1, has demonstrated preliminary antitumor activity in HCC. Here we describe a head-to-head Phase III study comparing the efficacy, safety and tolerability of tislelizumab with sorafenib as first-line treatment in unresectable HCC.

Suppression of LSD1 enhances the cytotoxic and apoptotic effects of regorafenib in hepatocellular carcinoma cells

Regorafenib has been approved to treat patients who have HCC progression after sorafenib failure, however, regorafenib also faces the risk of drug resistance and subsequent progression of HCC patients. As LSD1 inhibitors can alleviate acquired resistance to sorafenib, in this context, we are interested to investigate the role of LSD1 in regorafenib treatment. Firstly, over-expressed LSD1 was observed in HCC patients and predicted poor prognosis. However, regorafenib failed to suppress the expression of LSD1 in HCC cells. Thus, we hypothesized that LSD1 inhibition could enhance the anti-HCC activity of regorafenib. As expected, LSD1 knockdown could enhance anti-proliferation effect of regorafenib in HCC cells. LSD1 inhibitor SP2509 could enhance the cytotoxic and apoptotic effects of regorafenib in HCC cells. In addition, clinically used LSD1 inhibitor tranylcypromine also enhanced anti-HCC effect of regorafenib. Furthermore, LSD1 suppressed by SP2590 or tranylcypromine could alleviate the activated p-AKT (ser473) induced by regorafenib in HCC cells. Thus, inhibiting LSD1 might be an attractive target for regorafenib sensitization and clinical HCC therapy, our findings could help to elucidate more effective therapeutic options for HCC patients.

Ramucirumab after sorafenib in patients with advanced hepatocellular carcinoma and increased α-fetoprotein concentrations (REACH-2): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

Patients with advanced hepatocellular carcinoma and increased α-fetoprotein concentrations have poor prognosis. We aimed to establish the efficacy of ramucirumab in patients with advanced hepatocellular carcinoma and α-fetoprotein concentrations of 400 ng/mL or higher.

METHODS

REACH-2 was a randomised, double-blind, placebo-controlled, phase 3 trial done at 92 hospitals, clinics, and medical centres in 20 countries. Eligible patients were aged 18 years or older and had histologically or cytologically confirmed hepatocellular carcinoma, or diagnosed cirrhosis and hepatocellular carcinoma, Barcelona Clinic Liver Cancer stage B or C disease, Child-Pugh class A liver disease, Eastern Cooperative Oncology Group (ECOG) performance statuses of 0 or 1, α-fetoprotein concentrations of 400 ng/mL or greater, and had previously received first-line sorafenib. Participants were randomly assigned (2:1) via an interactive web response system with a computer-generated random sequence to 8 mg/kg intravenous ramucirumab every 2 weeks or placebo. All patients received best supportive care. The primary endpoint was overall survival. Secondary endpoints were progression-free survival, proportion of patients achieving an objective response, time to radiographic progression, safety, time to deterioration in scores on the Functional Assessment of Cancer Therapy Hepatobiliary Symptom Index 8 (FHSI-8), and time to deterioration in ECOG performance status. We also pooled individual patient data from REACH-2 with data from REACH (NCT01140347) for patients with α-fetoprotein concentrations of 400 ng/mL or greater. Efficacy analyses were by intention to treat, whereas safety analyses were done in all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT02435433.

FINDINGS

Between July 26, 2015, and Aug 30, 2017, 292 patients were randomly assigned, 197 to the ramucirumab group and 95 to the placebo group. At a median follow-up of 7·6 months (IQR 4·0-12·5), median overall survival (8·5 months [95% CI 7·0-10·6] vs 7·3 months [5·4-9·1]; hazard ratio [HR] 0·710 [95% CI 0·531-0·949]; p=0·0199) and progression-free survival (2·8 months [2·8-4·1] vs 1·6 months [1·5-2·7]; 0·452 [0·339-0·603]; p<0·0001) were significantly improved in the ramucirumab group compared with the placebo group. The proportion of patients with an objective response did not differ significantly between groups (nine [5%] of 197 vs one [1%] of 95; p=0·1697). Median time to deterioration in FHSI-8 total scores (3·7 months [95% CI 2·8-4·4] vs 2·8 months [1·6-2·9]; HR 0·799 [95% CI 0·545-1·171]; p=0·238) and ECOG performance statuses (HR 1·082 [95% CI 0·639-1·832]; p=0·77) did not differ between groups. Grade 3 or worse treatment-emergent adverse events that occurred in at least 5% of patients in either group were hypertension (25 [13%] in the ramucirumab group vs five [5%] in the placebo group), hyponatraemia (11 [6%] vs 0) and increased aspartate aminotransferase (six [3%] vs five [5%]). Serious adverse events of any grade and cause occurred in 68 (35%) patients in the ramucirumab group and 28 (29%) patients in the placebo group. Three patients in the ramucirumab group died from treatment-emergent adverse events that were judged to be related to study treatment (one had acute kidney injury, one had hepatorenal syndrome, and one had renal failure).

INTERPRETATION

REACH-2 met its primary endpoint, showing improved overall survival for ramucirumab compared with placebo in patients with hepatocellular carcinoma and α-fetoprotein concentrations of at least 400 ng/mL who had previously received sorafenib. Ramucirumab was well tolerated, with a manageable safety profile. To our knowledge, REACH-2 is the first positive phase 3 trial done in a biomarker-selected patient population with hepatocellular carcinoma.

FUNDING

Eli Lilly.

Lysyl oxidase assists tumor‑initiating cells to enhance angiogenesis in hepatocellular carcinoma

A highly tumorigenic and malignant sub‑population of HCC containing tumor‑initiating cells (TICs) are defined by high self‑renewal and sphere formation ability. Lysyl oxidase (LOX) regulates various factors involved in extracellular matrix (ECM) maintenance, migration and angiogenesis. Certain reports have demonstrated the role of LOX in ECM crosslinking, however, the cancer‑promoting effects of LOX in HCC remain unclear, and whether LOX has a role in the regulation of angiogenesis in HCC TICs has not been elucidated. In the current study, RNA sequencing using next‑generation sequencing technology and bioinformatics analyses revealed that LOX gene expression was significantly upregulated in cell spheres. Sphere cells may form tumors with more vascular enrichment compared with tumors produced from adherent cells, as observed in a mouse xenograft model. LOX expression is correlated with increased vascular endothelial growth factor (VEGF) and platelet‑derived growth factor, as demonstrated by analyses of The Cancer Genome Atlas and Gene Expression Omnibus databases. Conditioned media obtained from LOX‑overexpressing tumor cells stimulated angiogenesis via secreted VEGF and enhanced the tube formation capacity of endothelial cells. Furthermore, these functional behaviors were blocked by the LOX inhibitor β‑aminopropionitrile. These findings provide novel mechanistic insight into the pivotal role of LOX in the regulation of TICs in HCC. Combination of LOX inhibitor with sorafenib is a potentially advantageous strategy for HCC therapy.

Regorafenib: a promising treatment for hepatocellular carcinoma

Introduction: Hepatocellular carcinoma (HCC) is one of the most frequent malignant tumors with 854,000 new cases per year and represents the second most frequent cause of cancer-death. Despite surveillance, the number of patients that are diagnosed at a stage in which they are eligible for curative treatments ranges from 30% to 60%. Advanced HCC (BCLC-C) is characterized by a median survival of 6 months. Sorafenib, the first systemic drug proven to be effective in prolonging survival of unresectable HCC, was approved by the FDA in 2007 but no second-line treatment was available for a decade for patients progressing on sorafenib. Finally, in 2016, the RESORCE trial demonstrated regorafenib as an effective second-line treatment. Areas covered: In this manuscript, the authors review the principal preclinical and clinical trials on regorafenib used in the treatment of unresectable HCC patients progressing on sorafenib and highlight both the advantages and the limitations of this drug. Expert opinion: Regorafenib is the only second-line treatment available for patients progressing on sorafenib. Despite its promising clinical application, many doubts still remain, necessitating further investigation to explore the tolerability of this drug in Child-Pugh B and sorafenib-intolerant patients, while its scarce cost-effectiveness must also be improved.

Abnormal expression of HMGB-3 is significantly associated with malignant transformation of hepatocytes

AIM

To explore the relationship between dynamic expression of high mobility group box-3 (HMGB3) and malignant transformation of hepatocytes.

METHODS

Expression of HMGB family proteins were observed in rat hepatocarcinogenesis models induced with 2-acetylaminofluorene. Alterations of HMGB3 were analyzed at the mRNA level by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and at the protein level by immunohistochemistry or Western blotting. HMGB3 in human liver cancer tissues were evaluated using bioinformatics databases from GEO, TCGA, and Oncomine. A specific HMGB3-shRNA was used to knock down HMGB3 expression in order to investigate its effects on proliferation and cell cycle in vitro and in vivo.

RESULTS

Elevated HMGB3 levels were first reported in hepatocarcinogenesis, with increasing expression from normal liver to cancer. Bioinformatic databases showed that HMGB3 expression in hepatocellular carcinoma tissues was significantly higher than that in normal liver tissues. Higher HMGB3 expression was discovered in liver cancer cells compared with LO2 cells in vitro. According to gene set enrichment analysis, HMGB3 mRNA levels were correlated with cell cycle and DNA replication pathways. Knocking down HMGB3 by specific shRNA significantly inhibited proliferation of HepG2 cells by cell cycle arrest and downregulating DNA replication related genes (cyclin B1, FEN1, and PCNA) at the mRNA and protein level. Furthermore, silencing HMGB3 significantly inhibited xenograft tumor growth (measured by Ki67) in vivo.

CONCLUSION

HMGB3 is involved in malignant transformation of hepatocytes and could be a useful biomarker for diagnosis and a potential target for therapy of liver cancer.

Recent developments with immunotherapy for hepatocellular carcinoma

INTRODUCTION

Immunotherapy is on the way to become the new standard of care for advanced hepatocellular carcinoma (HCC) worldwide. With higher rates of objective responses, and overall less side effects compared to tyrosine-kinase inhibitors (TKIs) immunotherapeutics will probably replace sorafenib from standard first-line treatment.

AREAS COVERED

This review covers recent clinical data on systemic agents and ongoing trials in patients with advanced HCC focusing on immunotherapy.

EXPERT OPINION

In unselected patients with advanced HCC immunotherapeutics, namely the programmed cell death-1 (PD-1) antibodies, nivolumab and pembrolizumab have shown promising efficacy in therapy-naïve, as well as pre-treated patients with advanced HCC. However, only 10-20 percent of treated patients show an objective and durable response to the indicated therapeutics. Therefore, combination therapies including different immunotherapeutics, e.g. PD-1/programmed cell death 1 ligand 1 (PD-L1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) antibodies, or combinations of immunotherapeutics and small molecules, or bifunctional antibodies will be needed to improve response rates.

ABBREVIATIONS

HCC: hepatocellular carcinoma; TKI: tyrosine-kinase inhibitors; PD-1: programmed death receptor-1; PD-L1: programmed cell death 1 ligand 1; CTLA-4: cytotoxic T-lymphocyte-associated Protein 4; CAR-T: chimeric T cell receptors; TACE: transarterial chemoembolization; SIRT: selective internal radiation therapy; SBRT: stereotactic body radiation therapy; VEGF: vascular endothelial growth factor; MEK: mitogen-activated protein kinase kinase; NK cell: natural killer cell; TGFβ: transforming growth factor-β; OV: Oncolytic viruses; PFU: plaque-forming unit.

Precision oncology in liver cancer

With the widespread adoption of molecular profiling in clinical oncology practice, many physicians are faced with making therapeutic decisions based upon isolated genomic alterations. For example, epidermal growth factor receptor tyrosine kinase inhibitors (TKIs) are effective in EGFR-mutant non-small cell lung cancers (NSCLC) while anti-EGFR monoclonal antibodies are ineffective in Ras-mutant colorectal cancers. The matching of mutations with drugs aimed at their respective gene products represents the current state of "precision" oncology. Despite the great expectations of this approach, only a fraction of cancers responds to 'targeted' interventions, and many early responders will ultimately develop resistance to these agents. The underwhelming success of mutation-driven therapies across all cancer types is not due to an inability to detect genetic changes in tumors; rather a deficit in functional insight into the genomic alterations that give rise to each cancer. The Achilles heel of precision oncology thus remains the lack of a robust functional understanding of an individual cancer genome that then allows prediction of the best therapy and resultant outcome for that patient. Current practice focuses on one 'actionable' mutation at a time, while solid cancers typically possess many mutations that involve different cellular sub-populations within a tumor. No method or platform currently exists to guide the interpretation of these complex data, nor to accurately predict response to treatment. This problem is particularly germane to primary liver cancers (PLC), for which only a handful of targeted therapies have been introduced. Here, we will review strategies aimed at overcoming some of these challenges in precision oncology, using liver cancer as an example.

A quantitative proteomic response of hepatocellular carcinoma Hep3B cells to danusertib, a pan-Aurora kinase inhibitor

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide, but the overall prognosis remains disappointing especially in the advanced-stage patients. Aberration expression of Aurora kinases is tumorigenic and thus it has attracted interests as therapeutic targets in cancer treatment. Here, we investigated the proteomic response of HCC Hep3B cells to danusertib (Danu), a pan-Aurora kinase inhibitor, and then validated the proteomic results based on stable-isotope labeling by amino acids in cell culture (SILAC). The proteomic data identified that Danu modulated the expression of 542 protein molecules (279 up-regulated; 260 down-regulated; 3 stable). Ingenuity pathway analysis (IPA) and KEGG pathway analysis identified 107 and 24 signaling pathways were regulated by Danu, respectively. IPA analysis showed cellular growth and proliferation, and cell death and survival were among the top five molecular and cellular functions regulated by Danu. The verification experiments showed that Danu inhibited the proliferation of Hep3B cells with a 24-hr IC50 value of 22.03 µM. Danu treatment also arrested Hep3B cells in G2/M phase via regulating the expression of key cell cycle regulators and induced apoptosis via mitochondria-dependent pathway in a dose-dependent manner. Besides, Danu induced a marked autophagy, and inhibition of autophagy enhanced the anticancer effects of Danu, indicating a cyto-protective role of Danu-induced autophagy. Our proteomic data and Western blotting assays showed the PI3K/Akt/mTOR signaling pathway was involved in the inducing effect of Danu on apoptosis and autophagy. Collectively, our findings have demonstrated that the Aurora kinases inhibition with danusertib results in global proteomic response and exerts anticancer effects in Hep3B cells involving regulation of cell cycle, apoptosis and autophagy and associated signaling pathways.

BRAF in Lung Cancers: Analysis of Patient Cases Reveals Recurrent BRAF Mutations, Fusions, Kinase Duplications, and Concurrent Alterations

Purpose

Dabrafenib and trametinib are approved for the management of advanced non-small-cell lung cancers (NSCLCs) that harbor BRAF V600E mutations. Small series and pan-cancer analyses have identified non-V600 alterations as therapeutic targets. We sought to examine a large genomic data set to comprehensively characterize non-V600 BRAF alterations in lung cancer.

Patients and Methods

A total of 23,396 patients with lung cancer provided data to assay with comprehensive genomic profiling. Data were reviewed for predicted pathogenic BRAF base substitutions, short insertions and deletions, copy number changes, and rearrangements.

Results

Adenocarcinomas represented 65% of the occurrences; NSCLC not otherwise specified (NOS), 15%; squamous cell carcinoma, 12%; and small-cell lung carcinoma, 5%. BRAF was altered in 4.5% (1,048 of 23,396) of all tumors; 37.4% (n = 397) were BRAF V600E, 38% were BRAF non-V600E activating mutations, and 18% were BRAF inactivating. Rearrangements were observed at a frequency of 4.3% and consisted of N-terminal deletions (NTDs; 0.75%), kinase domain duplications (KDDs; 0.75%), and BRAF fusions (2.8%). The fusions involved three recurrent fusion partners: ARMC10, DOCK4, and TRIM24. BRAF V600E was associated with co-occurrence of SETD2 alterations, but other BRAF alterations were not and were instead associated with CDKN2A, TP53, and STK11 alterations (P < .05). Potential mechanisms of acquired resistance to BRAF V600E inhibition are demonstrated.

Conclusion

This series characterized the frequent occurrence (4.4%) of BRAF alterations in lung cancers. Recurrent BRAF alterations in NSCLC adenocarcinoma are comparable to the frequency of other NSCLC oncogenic drivers, such as ALK, and exceed that of ROS1 or RET. This work supports a broad profiling approach in lung cancers and suggests that non-V600E BRAF alterations represent a subgroup of lung cancers in which targeted therapy should be considered.

Insights into the hepatocellular carcinoma patient journey: results of the first global quality of life survey

AIM

To better understand the hepatocellular carcinoma (HCC) patient journey, we conducted a patient survey across 13 countries.

METHODS

The survey included closed- and open-ended questions developed using an iterative process to gather information on demographics, diagnosis and treatment. Patients self-selected or were directed to the online survey by their doctor.

RESULTS

A total of 256 patients completed the survey. More than two-thirds (68%) felt they did not receive enough information about HCC at diagnosis. Treatments included oral anticancer therapy, transarterial chemoembolization (TACE), and selective internal radiation therapy (SIRT). A total of 81% receiving sorafenib, 45% receiving SIRT and 32% receiving TACE reported impaired quality-of-life (QoL). A total of 42, 19 and 0% of patients using sorafenib rated their current QoL as 'poor', 'good' and 'excellent', respectively; compared with SIRT (22, 33 and 6%) or TACE (11, 37 and 13%).

CONCLUSION

Most patients with HCC require additional accessible information. People with incurable HCC require treatments that preserve QoL.

Circulating tumor cells as liquid biomarker for high HCC recurrence risk after curative liver resection

Background

Early hepatocellular carcinoma (HCC) has a limited prognosis due to recurrence rates of more than 50% after liver resection. Recurrence within two years is believed to be caused by untraceable micro metastases at the time of resection. The objective of this study was to investigate EpCAM-positive circulating tumor cells (CTC) as liquid biomarker to identify patients with high risk of recurrence after liver resection.

Methods

61 patients undergoing resection between 2011 and 2015 were consecutively enrolled. Blood specimens were obtained prior to surgery and processed with the CellSearch^TM system, detecting EpCAM-positive CTC. The primary endpoint was recurrence-free survival (RFS).

Results

13 women and 44 men (63.6 ± 11.1 years) were finally evaluated. CTC-positive patients had a significantly higher risk of recurrence with a hazard ratio (HR) of 2.3 (p=0.027), and a shorter RFS compared to CTC-negative patients (5.0 ± 1.5 vs. 12.0 ± 2.5 months, p=0.039). As expected, incomplete resection (R1) was also associated with shorter RFS (HR=2.6, p=0.035), but vascular invasion was not. However, the predictive power of CTC status was independent of R1.

Conclusion

Bloodstream detection of CTC prior to curative-intended liver resection discloses an elevated risk of HCC recurrence and could identify patients, who might benefit from adjuvant treatment.

Targeted therapy and personalized medicine in hepatocellular carcinoma: drug resistance, mechanisms, and treatment strategies

Hepatocellular carcinoma (HCC) is characterized by a growing number of new cases diagnosed each year that is nearly equal to the number of deaths from this cancer. In a majority of the cases, HCC is associated with the underlying chronic liver disease, and it is diagnosed in advanced stage of disease when curative treatment options are not applicable. Sorafenib is a treatment of choice for patients with performance status 1 or 2 and/or macrovascular invasion or extrahepatic spread, and regorafenib is the only systemic treatment found to provide survival benefit in HCC patients progressing on sorafenib treatment. Other drugs tested in different trials failed to demonstrate any benefit. Disappointing results of numerous trials testing the efficacy of various drugs indicate that HCC has low sensitivity to chemotherapy that is in great part caused by multidrug resistance. Immunotherapy for HCC is a new challenging treatment option and involves immune checkpoint inhibitors/antibody-based therapy and peptide-based vaccines. Another challenging approach is microRNA-based therapy that involves two strategies. The first aims to inhibit oncogenic miRNAs by using miRNA antagonists and the second strategy is miRNA replacement, which involves the reintroduction of a tumor-suppressor miRNA mimetic to restore a loss of function.

Advances and Future Directions in the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. Liver transplant is considered the gold standard for curative therapy for HCC when patients are not candidates for surgical resection or ablation. Because a subset of patients with HCC have a survival rate with liver transplantation that is comparable to that of cirrhotic patients without tumors, the organ allocation system allows for increased priority for transplant in potential recipients within the Milan criteria. With the recent change in the Model for End-Stage Liver Disease exception point allocation, patients with HCC will now need to wait at least 6 months before being awarded extra points. This extension leads to increased time on the transplant waiting list and underscores the importance of locoregional therapy to contain the tumor burden. Fortunately, there has been significant progress in therapy for HCC in the past few decades, namely due to advances in interventional radiology, radiotherapy, and expanded surgical and transplant criteria. Recent advances in immunotherapy also provide promising options for patients who are not candidates for other therapies. This article highlights the major therapeutic options for HCC, including surgical resection, liver transplant, thermal and nonthermal ablation, chemoembolization, radiotherapy, and systemic chemotherapy, as well as discusses the evidence supporting these approaches.

Evolving role of Sorafenib in the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant diseases worldwide and comes third in cancer-related mortality. Although there is a broad spectrum of treatment options to choose from, only a few patients are eligible candidates to receive a curative therapy according to their stage of disease, and thus palliative treatment is implemented in the majority of the patients suffering from liver cancer. Sorafenib, a multikinase inhibitor, is the only currently approved agent for systemic therapy in patients with advanced stage HCC and early stage liver disease. It has been shown to improve the overall survival, but with various side effects, while its cost is not negligible. Sorafenib has been in the market for a decade and has set the stage for personalized targeted therapy. Its role during this time has ranged from monotherapy to neoadjuvant and adjuvant treatment with surgical resection, liver transplantation and chemoembolization or even in combination with other chemotherapeutic agents. In this review our aim is to highlight in depth the current position of Sorafenib in the armamentarium against HCC and how that has evolved over time in its use either as a single agent or in combination with other therapies.

Precision medicine for hepatocellular carcinoma: driver mutations and targeted therapy

Hepatocellular carcinoma (HCC) is the third most frequent cause of tumor-related mortality and there are an estimated approximately 850,000 new cases annually. Most HCC patients are diagnosed at middle or advanced stage, losing the opportunity of surgery. The development of HCC is promoted by accumulated diverse genetic mutations, which confer selective growth advantages to tumor cells and are called "driver mutations". The discovery of driver mutations provides a novel precision medicine strategy for late stage HCC, called targeted therapy. In this review, we summarized currently discovered driver mutations and corresponding signaling pathways, made an overview of identification methods of driver mutations and genes, and classified targeted drugs for HCC. The knowledge of mutational landscape deepen our understanding of carcinogenesis and promise future precision medicine for HCC patients.