LY3214996 relieves acquired resistance to sorafenib in hepatocellular carcinoma cells

Background: Sorafenib, an oral multi-kinase inhibitor of rapidly accelerated fibrosarcoma; vascular endothelial growth factor receptor-2/3, platelet-derived growth factor receptor, c-Kit, and Flt-3 signaling, is approved for treatment of advanced hepatocellular carcinoma (HCC). However, the benefit of sorafenib is often diminished because of acquired resistance through the reactivation of ERK signaling in sorafenib-resistant HCC cells. In this work, we investigated whether adding LY3214996, a selective ERK1/2 inhibitor, to sorafenib would increase the anti-tumor effectiveness of sorafenib to HCC cells.Methods: The Huh7 cell line was used as a cell model for treatment with sorafenib, LY3214996, and their combination. Phosphorylation of the key kinases in the Ras/Raf/MAPK and PI3K/Akt pathways, protein expression of the cell cycle, and apoptosis migration were assessed with western blot. MTT and colony-formation assays were used to evaluate cell proliferation. Wound-healing assay was used to assess cell migration. Cell cycle and apoptosis analyses were conducted with flow cytometry.Results: LY3214996 decreased phosphorylation of the Ras/Raf/MAPK and PI3K/Akt pathways, including p-c-Raf, p-P90RSK, p-S6K and p-eIF4EBP1 activated by sorafenib, despite increased p-ERK1/2 levels. LY3214996 increased the anti-proliferation, anti-migration, cell-cycle progression, and pro-apoptotic effects of sorafenib on Huh7^R cells.Conclusions: Reactivation of ERK1/2 appears to be a molecular mechanism of acquired resistance of HCC to sorafenib. LY3214996 combined with sorafenib enhanced the anti-tumor effects of sorafenib in HCC. These findings form a theoretical basis for trial of LY3214996 combined with sorafenib as second-line treatment of sorafenib-resistant in advanced HCC.     

First-in-Class Selective HDAC6 Inhibitor (ACY-1215) Has a Highly Favorable Safety Profile in Patients with Relapsed and Refractory Lymphoma

Lessons Learned

• Oral selective HDAC6 inhibitors could allow for decreased toxicity compared to pan‐class inhibitors, and increased ease of use.
• ACY‐1215 is well tolerated and led to disease stabilization in 50% of patients treated on a twice‐daily dosing schedule.
• Rational drug combinations with ACY‐1215 improve efficacy in patients with lymphoma.
• Biomarkers such as XBP‐1 level or HDAC6‐score may improve patient selection.

BackgroundACY‐1215, ricolinostat, is an oral, first‐in‐class isoform‐selective HDAC6 inhibitor. HDAC6 is a class IIb deacetylase and plays a critical role in protein homeostasis via the unfolded protein response (UPR). Lymphocytes generate a large repertoire of antibodies and depend on an activated UPR to maintain proteostasis. Lymphomas utilize this biology to evade programmed cell death. In preclinical models of lymphoma, ACY‐1215 disrupted proteostasis, triggering apoptosis.MethodsWe translated these findings into a multi‐institution, open‐label, dose‐escalation phase Ib/II study aimed to determine the safety and efficacy in patients with relapsed and refractory lymphoma.ResultsTwenty‐one patients with heavily pretreated lymphoma were accrued. Patients in the phase Ib portion were enrolled on one of two dose cohorts [Arm A: 160 mg daily (n = 3) or Arm B: 160 mg twice daily (n = 10)]. ACY‐1215 was well tolerated. There were no dose limiting toxicities. Most adverse events were grade 1–2, including diarrhea (57%), nausea (57%), and fatigue (43%). Grade 3–4 toxicities were rare and included anemia (9.5%) and hypercalcemia (9.5%). An additional 8 patients were enrolled on the phase II portion, at 160 mg twice daily. Sixteen patients were evaluable for response. ACY‐1215 did not result in any complete or partial responses in patients treated. Eight patients had stable disease (50%) lasting a median duration of 4.5 months, all of whom were treated twice daily. Disease progressed in eight patients (50%) at cycle 2. Five patients were not evaluable due to disease progression prior to cycle 2. The median PFS was 56 days.ConclusionACY‐1215 is an oral selective HDAC6 inhibitor that was safe in patients with relapsed and refractory lymphoid malignancies and led to disease stabilization in half of the evaluable patients.     

The Proximity of Spatial Clusters of Low Birth Weight and Risk Factors: Defining a Neighborhood for Focused Interventions

Maternal and Child Health Journal - Low birth weight (LBW) is associated with significant mortality and morbidity and remains a significant preventable problem. Risk factors include socioeconomic,...     

Does l -carnitine supplementation affect serum levels of enzymes mainly produced by liver? A systematic review and meta-analysis of randomized controlled clinical trials

l-carnitine supplementation is proposed to reduce liver enzymes levels; however, previous findings were equivocal. The current systematic review and meta-a