Sorafenib for the treatment of hepatocellular carcinoma across geographic regions

Ferroptosis: Shedding Light on Mechanisms and Therapeutic Opportunities in Liver Diseases

Cell death is a vital physiological or pathological phenomenon in the development process of the organism. Ferroptosis is a kind of newly-discovered regulated cell death (RCD), which is different from other RCD patterns, such as apoptosis, necrosis and autophagy at the morphological, biochemical and genetic levels. It is a kind of iron-dependent mode of death mediated by lipid peroxides and lipid reactive oxygen species aggregation. Noteworthily, the number of studies focused on ferroptosis has been increasing exponentially since ferroptosis was first found in 2012. The liver is the organ that stores the most iron in the human body. Recently, it was frequently found that there are different degrees of iron metabolism disorder and lipid peroxidation and other ferroptosis characteristics in various liver diseases. Numerous investigators have discovered that the progression of various liver diseases can be affected via the regulation of ferroptosis, which may provide a potential therapeutic strategy for clinical hepatic diseases. This review aims to summarize the mechanism and update research progress of ferroptosis, so as to provide novel promising directions for the treatment of liver diseases.

Influence of Probenecid on the Pharmacokinetics and Pharmacodynamics of Sorafenib

Prior studies have demonstrated an organic anion transporter 6 (OAT6)-mediated accumulation of sorafenib in keratinocytes. The OAT6 inhibitor probenecid decreases sorafenib uptake in skin and might, therefore, decrease sorafenib-induced cutaneous adverse events. Here, the influence of probenecid on sorafenib pharmacokinetics and toxicity was investigated. Pharmacokinetic sampling was performed in 16 patients on steady-state sorafenib treatment at days 1 and 15 of the study. Patients received sorafenib (200–800 mg daily) in combination with probenecid (500 mg two times daily (b.i.d.)) on days 2–15. This study was designed to determine bioequivalence with geometric mean Area under the curve from zero to twelve hours (AUC_{0–12 h}) as primary endpoint. During concomitant probenecid, sorafenib plasma AUC_{0–12 h} decreased by 27% (90% CI: −38% to −14%; P < 0.01). Furthermore, peak and trough levels of sorafenib, as well as sorafenib concentrations in skin, decreased to a similar extent in the presence of probenecid. The metabolic ratio of sorafenib-glucuronide to parent drug increased (+29%) in the presence of probenecid. A decrease in systemic sorafenib concentrations during probenecid administration seems to have influenced cutaneous concentrations. Since sorafenib-glucuronide concentrations increased compared with sorafenib and sorafenib-N-oxide, probenecid may have interrupted enterohepatic circulation of sorafenib by inhibition of the organic anion transporting polypeptides 1B1 (OATP1B1). Sorafenib treatment with probenecid is, therefore, not bioequivalent to sorafenib monotherapy. A clear effect of probenecid on sorafenib toxicity could not be identified in this study.

Brivanib in combination with Notch3 silencing shows potent activity in tumour models

BACKGROUND

Sorafenib is the first targeted agent proven to improve survival of patients with advanced hepatocellular carcinoma (HCC) and it has been used in first line treatments with heterogeneous response across patients. Most of the promising agents evaluated in first-line or second-line phase III trials for HCC failed to improve patient survival. The absence of molecular characterisation, including the identification of pathways driving resistance might be responsible for these disappointing results.

METHODS

2D DIGE and MS analyses were used to reveal proteomic signatures resulting from Notch3 inhibition in HepG2 cells, combined with brivanib treatment. The therapeutic potential of Notch3 inhibition combined with brivanib treatment was also demonstrated in a rat model of HCC and in cell lines derived from different human cancers.

RESULTS

Using a proteomic approach, we have shown that Notch3 is strongly involved in brivanib resistance through a p53-dependent regulation of enzymes of the tricarboxylic acid (TCA), both in vitro and in vivo.

CONCLUSION

We have demonstrated that regulation of the TCA cycle is a common mechanism in different human cancers, suggesting that Notch3 inhibitors combined with brivanib treatment may represent a strong formulation for the treatment of HCC as well as Notch3-driven cancers.

Role of ferroptosis in hepatocellular carcinoma

PURPOSE

Hepatocellular carcinoma (HCC) is a complicated disease with low survival rate due to frequent recurrence and the lack of efficient therapies. For advanced HCC, sorafenib, as the only approved first-line drug for HCC, improves the survival to some extent, but depressingly with severe adverse effects and emerging resistance conditions, which cause a poor prognosis. Ferroptosis is a new recognized way of non-apoptosis-regulated cell death, characterized by the iron-dependent accumulation of lipid hydroperoxides, showing a tremendous promising in the therapy of cancer, especially in HCC. To provide ideas for the diagnosis and treatment of HCC, we summarized the role of ferroptosis in HCC.

METHODS

The relevant literature from PubMed is reviewed in this article.

RESULTS

Interestingly enough, investigators have found sorafenib can induce ferroptosis in HCC. Moreover, recent researches reported increasing pathways and mechanisms related to ferroptosis in HCC such as TP53 and Rb, and strategies to improve sorafenib resistance by targeting ferroptosis. In addition, other drugs were reported to induce ferroptosis in HCC such as erastin and showed good efficacy in vivo and in vitro.

CONCLUSION

In this review, we summarize pathways and mechanisms of ferroptosis in HCC and other digestive system neoplasms such as gastric cancer, pancreatic cancer and colorectal cancer and point out the trends of ferroptosis in HCC.

Melatonin enhances the anti-tumor effect of sorafenib via AKT/p27-mediated cell cycle arrest in hepatocarcinoma cell lines

Proposed model elucidating the role of MT in regulating the proliferation of hepatocellular carcinoma (HCC) cells treated with sorafenib.

First- and Second-Line Targeted Systemic Therapy in Hepatocellular Carcinoma-An Update on Patient Selection and Response Evaluation

Advanced hepatocellular carcinoma (HCC) with vascular invasion and/or extrahepatic spread and preserved liver function, according to stage C of the Barcelona Clinic Liver Cancer (BCLC) classification, has a dismal prognosis. The multi-targeted tyrosine-kinase receptor inhibitor (TKI) sorafenib is the only proven active substance in systemic HCC therapy for first-line treatment. In this review, we summarize current aspects in patient selection and management of side effects, and provide an update on response evaluation during first-line sorafenib therapy. Since second-line treatment options have been improved with the successful completion of the RESORCE trial, demonstrating a survival benefit for second-line treatment with the TKI regorafenib, response monitoring during first-line therapy will be critical to deliver optimal systemic therapy in HCC. To this regard, specific side effects, in particular worsening of arterial hypertension and diarrhea, might suggest treatment response during first-line sorafenib therapy; however, clear predictive clinical markers, as well as laboratory test or serum markers, are not established. Assessment of radiologic response according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) is helpful to identify patients who do not benefit from sorafenib treatment.

Emerging role of dual antiplatelet therapy in the prevention of hepatitis B virus-associated hepatocellular carcinoma

Platelets, the chief effectors of vascular homeostasis, have been identified as important players in the pathogenesis of both acute and chronic liver disease in preclinical models of hepatitis B viral infection. Platelets are thought to promote the accumulation of virus-specific T-cells into the liver parenchyma. Importantly, the inhibition of platelet activation by clinically relevant doses of aspirin and clopidogrel was able to reduce immune-mediated necroinflammatory liver disease, extracellular matrix deposition, and hepatocellular carcinoma development; the same treatment was able to improve overall survival. These results strongly support the design of clinical trials aiming to define the potential of antiplatelet therapy in the prevention of hepatitis B virus-associated hepatocellular carcinoma.

Synergistic inhibitory effect of hyperbaric oxygen combined with sorafenib on hepatoma cells

OBJECTIVES

Hypoxia is a common phenomenon in solid tumors, associated with chemotherapy and radiotherapy resistance, recurrence and metastasis. Hyperbaric oxygen (HBO) therapy can increase tissue oxygen pressure and content to prevent the resistance, recurrence and metastasis of cancer. Presently, Sorafenib is a first-line drug, targeted for hepatocellular carcinoma (HCC) but effective in only a small portion of patients and can induce hypoxia. The purpose of this study is to investigate the effect of HBO in combination with sorafenib on hepatoma cells.

METHODS

Hepatoma cell lines (BEL-7402 and SK-Hep1) were treated with HBO at 2 atmosphere absolute pressure for 80 min per day or combined with sorafenib or cisplatin. At different time points, cells were tested for cell growth, colony formation, apoptosis, cell cycle and migration. Finally, miRNA from the hepatoma cells was detected by microRNA array and validated by qRT-PCR.

RESULTS

Although HBO, sorafenib or cisplatin alone could inhibit growth of hepatoma cells, HBO combined with sorafenib or cisplatin resulted in much greater synergistic growth inhibition (cell proliferation and colony formation) in hepatoma cells. Similarly, the synergistic effect of HBO and sorafenib on induction of apoptosis was also observed in hepatoma cells. HBO induced G1 arrest in SK-Hep1 not in BEL-7402 cells, but enhanced cell cycle arrest induced by sorafenib in BEL-7402 treated cells. However, HBO had no obvious effect on the migration of hepatoma cells, and microRNA array analysis showed that hepatoma cells with HBO treatment had significantly different microRNA expression profiles from those with blank control.

CONCLUSIONS

We show for the first time that HBO combined with sorafenib results in synergistic growth inhibition and apoptosis in hepatoma cells, suggesting a potential application of HBO combined with sorafenib in HCC patients. Additionally, we also show that HBO significantly altered microRNA expression in hepatoma cells.