resminostat and Liver-Neoplasms

No established therapies for patients with hepatocellular carcinoma (HCC) and progression on first-line sorafenib treatment currently exist. This phase I/II trial investigated safety, pharmacokinetics and potential biomarkers of the histone deacetylase inhibitor resminostat and a combination therapy with resminostat and sorafenib.. Patients with HCC and radiologically confirmed progression on sorafenib were treated in an exploratory, multi-center, open-label, uncontrolled, non-randomized, parallel group phase I/II study. In the combination group (n=38) four dose levels ranged from daily 200 to 600mg resminostat plus 400 to 800mg sorafenib. The monotherapy group (n=19) received 600mg resminostat.. 57 patients received treatment. Most common adverse events were gastrointestinal disorders, thrombocytopenia and fatigue. Median maximal histone deacetylase inhibition and highest increase in H4-acetylation matched Tmax of resminostat. Sorafenib or the Child-Pugh score did not affect typical pharmacokinetics characteristics of resminostat. Efficacy assessment as progression-free survival-rate after 6 treatment cycles (12weeks, primary endpoint) was 12.5% for resminostat and 62.5% for resminostat plus sorafenib. Median time to progression and overall survival were 1.8 and 4.1months for resminostat and 6.5 and 8.0months for the combination, respectively. Zinc finger protein 64 (ZFP64) baseline expression in blood cells was found to correlate with overall survival.. The combination of sorafenib and resminostat in HCC patients was safe and showed early signs of efficacy. Sorafenib did not alter the pharmacokinetic profile of resminostat or its histone deacetylase inhibitory activity in vivo. A prognostic and potentially predictive role of ZFP64 for treatment with resminostat should be further investigated in HCC and possibly other cancer indications.. No established therapy for patients with advanced hepatocellular carcinoma and progression under first-line systemic treatment with sorafenib currently exists. Epigenetic modulation by inhibition of histone deacetylases might be able to overcome therapy resistance. This exploratory phase I/II clinical study in patients with radiologically confirmed progression under first-line treatment with sorafenib investigated the histone deacetylases inhibitor resminostat as single agent or in combination with continued application of sorafenib.. The clinical trial has been registered at www.clinicaltrials.gov as NCT00943449.

Topics: Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Hepatocellular; Humans; Hydroxamic Acids; Liver Neoplasms; Niacinamide; Phenylurea Compounds; Sorafenib; Sulfonamides

In hepatocellular carcinoma (HCC), blood platelets have been linked to tumor growth, epithelial-to-mesenchymal transition (EMT), extrahepatic metastasis and a limited therapeutic response to the multikinase inhibitor (MKi) sorafenib, the standard of care in advanced HCC for the last decade. Recent clinical data indicated an improved overall survival for sorafenib in combination with the HDAC inhibitor resminostat in a platelet count dependent manner. Here, the impact of platelets on the sorafenib and resminostat drug effects in HCC cells was explored. In contrast to sorafenib, resminostat triggered an anti-proliferative response in HCC cell lines independent of platelets. As previously described, platelets induced invasive capabilities of HCC cells, a prerequisite for extravasation and metastasis. Importantly, the resminostat/sorafenib drug combination, but not the individual drugs, effectively blocked platelet-induced HCC cell invasion. Exploration of the molecular mechanism revealed that the combined drug action led to a reduction of platelet-induced CD44 expression and to the deregulation of several other epithelial and mesenchymal genes, suggesting interference with cell invasion via EMT. In addition, the drug combination decreased phosphorylated ERK level, indicating inhibition of the mitogenic signaling pathway MEK/ERK. Taken together, the resminostat plus sorafenib combination counteracts platelet-mediated cancer promoting effects in HCC cells.

Topics: Animals; Antineoplastic Agents; Blood Platelets; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Disease Models, Animal; Drug Therapy, Combination; Epithelial-Mesenchymal Transition; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Liver Neoplasms; Mice; Signal Transduction; Sorafenib; Sulfonamides

Over-expression and aberrant activation of histone deacetylases (HDACs) are often associated with poor prognosis of hepatocellular carcinoma (HCC). Here, we evaluated the potential anti-hepatocellular carcinoma (HCC) cell activity by resminostat, a novel pan HDAC inhibitor (HDACi). We demonstrated that resminostat induced potent cytotoxic and anti-proliferative activity against established HCC cell lines (HepG2, HepB3, SMMC-7721) and patient-derived primary HCC cells. Further, resminostat treatment in HCC cells activated mitochondrial permeability transition pore (mPTP)-dependent apoptosis pathway, which was evidenced by physical association of cyclophilin-D and adenine nucleotide translocator 1 (ANT-1), mitochondrial depolarization, cytochrome C release and caspase-9 activation. Intriguingly, the mPTP blockers (sanglifehrin A and cyclosporine A), shRNA knockdown of cyclophilin-D or the caspase-9 inhibitor dramatically attenuated resminostat-induced HCC cell apoptosis and cytotoxicity. Reversely, HCC cells with exogenous cyclophilin-D over-expression were hyper-sensitive to resminostat. Intriguingly, a low concentration of resminostat remarkably potentiated sorafenib-induced mitochondrial apoptosis pathway activation, leading to a profound cytotoxicity in HCC cells. The results of this preclinical study indicate that resminostat (or plus sorafenib) could be further investigated as a valuable anti-HCC strategy.

Topics: Apoptosis; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Proliferation; Cell Survival; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Liver Neoplasms; Mitochondrial Membrane Transport Proteins; Mitochondrial Permeability Transition Pore; Sulfonamides

Histone deacetylases (HDACs) hyper-activity in hepatocellular carcinoma (HCC) is often associated with patients' poor prognosis. Our previous study has shown that resminostat, a novel HDAC inhibitor (HDACi), activated mitochondrial permeability transition pore (mPTP)-dependent apoptosis pathway in HCC cells. Here we explored the potential resminostat resistance factor by focusing on mammalian target of rapamycin (mTOR). We showed that AZD-2014, a novel mTOR kinase inhibitor, potentiated resminostat-induced cytotoxicity and proliferation inhibition in HCC cells. Molecularly, AZD-2014 enhanced resminostat-induced mPTP apoptosis pathway activation in HCC cells. Inhibition of this apoptosis pathway, by the caspase-9 specific inhibitor Ac-LEHD-CHO, the mPTP blockers (sanglifehrin A/cyclosporine A), or by shRNA-mediated knockdown of mPTP component cyclophilin-D (Cyp-D), significantly attenuated resminostat plus AZD-2014-induced cytotoxicity and apoptosis in HCC cells. Significantly, mTOR shRNA knockdown or kinase-dead mutation (Asp-2338-Ala) also sensitized HCC cells to resminostat, causing profound cytotoxicity and apoptosis induction. Together, these results suggest that mTOR could be a primary resistance factor of resminostat. Targeted inhibition of mTOR may thus significantly sensitize HCC cells to resminostat.

Topics: Apoptosis; Benzamides; Carcinoma, Hepatocellular; Drug Synergism; Gene Silencing; Hep G2 Cells; Humans; Hydroxamic Acids; Liver Neoplasms; Mitochondrial Membrane Transport Proteins; Mitochondrial Permeability Transition Pore; Morpholines; Mutation; Pyrimidines; Sulfonamides; TOR Serine-Threonine Kinases