Exogenous albumin inhibits sorafenib-induced cytotoxicity in human cancer cell lines

Ferroptosis inhibitor alleviates sorafenib-induced cardiotoxicity by attenuating KLF11-mediated FSP1-dependent ferroptosis

Sorafenib is a standard first-line drug for advanced hepatocellular carcinoma, but the serious cardiotoxic effects restrict its therapeutic applicability. Here, we show that iron-dependent ferroptosis plays a vital role in sorafenib-induced cardiotoxicity. Remarkably, our in vivo and in vitro experiments demonstrated that ferroptosis inhibitor application neutralized sorafenib-induced heart injury. By analyzing transcriptome profiles of adult human sorafenib-treated cardiomyocytes, we found that Krüppel-like transcription factor 11 (KLF11) expression significantly increased after sorafenib stimulation. Mechanistically, KLF11 promoted ferroptosis by suppressing transcription of ferroptosis suppressor protein 1 (FSP1), a seminal breakthrough due to its ferroptosis-repressing properties. Moreover, FSP1 knockdown showed equivalent results to glutathione peroxidase 4 (GPX4) knockdown, and FSP1 overexpression counteracted GPX4 inhibition-induced ferroptosis to a substantial extent. Cardiac-specific overexpression of FSP1 and silencing KLF11 by an adeno-associated virus serotype 9 markedly improved cardiac dysfunction in sorafenib-treated mice. In summary, FSP1-mediated ferroptosis is a crucial mechanism for sorafenib-provoked cardiotoxicity, and targeting ferroptosis may be a promising therapeutic strategy for alleviating sorafenib-induced cardiac damage.

Parenteral Nanoemulsions Loaded with Combined Immuno- and Chemo-Therapy for Melanoma Treatment

High-grade melanoma remains a major life-threatening illness despite the improvement in therapeutic control that has been achieved by means of targeted therapies and immunotherapies in recent years. This work presents a preclinical-level test of a multi-pronged approach that includes the loading of immunotherapeutic (ICOS-Fc), targeted (sorafenib), and chemotherapeutic (temozolomide) agents within Intralipid^®, which is a biocompatible nanoemulsion with a long history of safe clinical use for total parenteral nutrition. This drug combination has been shown to inhibit tumor growth and angiogenesis with the involvement of the immune system, and a key role is played by ICOS-Fc. The inhibition of tumor growth in subcutaneous melanoma mouse models has been achieved using sub-therapeutic drug doses, which is most likely the result of the nanoemulsion's targeting properties. If translated to the human setting, this approach should therefore allow therapeutic efficacy to be achieved without increasing the risk of toxic effects.

Progress in Application of Nanotechnology in Sorafenib

Dysregulation of the tyrosine kinase signaling pathway is closely related to tumor development, and tyrosine kinase inhibitors are important targets for potential anticancer strategies. In particular, sorafenib, as a representative drug of multitarget tyrosine kinase inhibitors, has an important clinical status and is widely used for treating various solid tumors and diabetic complications. However, poor aqueous solubility of sorafenib, poor bioavailability of commonly used oral dose forms, poor accumulation at tumor sites, and severe off-target effects that tend to induce intolerable systemic side effects in patients have greatly reduced its therapeutic efficiency and limited its extensive clinical application. To improve the properties of sorafenib, increase the efficiency of clinical treatment, and overcome the increasingly prominent phenomenon of sorafenib resistance, multiple investigations have been conducted. Numerous studies have reported that the properties of nanomaterials, such as small particle size, large specific surface area, high surface activity and high adsorption capacity, make nanotechnology promising for the construction of ideal sorafenib nanodelivery systems to achieve timed and targeted delivery of sorafenib to tumors, prolong the blood circulation time of the drug, improve the utilization efficiency of the drug and reduce systemic toxic side effects. This review summarizes the progress of research applications in nanotechnology related to sorafenib, discusses the current problems, and expresses expectations for the prospect of clinical applications of sorafenib with improved performance.

In vitro relationship between serum protein binding to beta-carboline alkaloids: a comparative cytotoxic, spectroscopic and calorimetric assays

The work highlighted interaction of harmalol, harmaline and harmine with human serum albumin by biophysical and biochemical assays. Presence of serum protein in the media negatively affects the cytotoxicity of the alkaloids. MTT assay indicates concentration-dependent growth inhibitory effect of the alkaloids on A375, MDA-MB-231, HeLa, A549, ACHN and HepG₂ cell, having maximum cytotoxicity with GI₅₀ value of 6.5 μM on ACHN by harmine in 1% of fetal bovine serum. Detail cytotoxic studies on ACHN cell by harmine, the most cytotoxic among the three, reveal nucleosomal fragmentation, formation of comet tail, generation of reactive oxygen species, decreased mitochondrial membrane potential, up regulation of p53, caspase 3 and significant increase in G₂/M population that made the cancer cells prone to apoptosis. Furthermore, the findings unequivocally pointed out that harmine binds strongly to the protein with a binding constant of 5.53 × 10⁴ M^-1 followed by harmaline and least with harmalol. Thermodynamic results revealed enthalpy dominated, entropy favored, 1:1 binding. Molecular docking and circular dichroism suggested changed conformation of protein by partial unfolding on complexation. Further supported by infrared analysis where protein secondary structure was altered with a major decrease of α-helix from 53.68% (free protein) to 8-11% and change in β-sheet from 25.31% (free protein) to 1-6% upon binding, inducing partial protein destabilization. Site markers demonstrated site I (subdomain IIA) binding of the alkaloids to the protein. The results serve as data for the future development of serum protein-based targeted drugs. AbbreviationsCD: circular dichroism; FBS: fetal bovine serumFRETForster resonance energy transferFTIRFourier transform infraredHSAhuman serum albumin; ROS: reactive oxygen speciesCommunicated by Ramaswamy H. Sarma.