Stimulatory effects of sorafenib on human non‑small cell lung cancer cells in vitro by regulating MAPK/ERK activation

Inhalable spray-dried polycaprolactone-based microparticles of Sorafenib Tosylate with promising efficacy on A549 cells

The study developed and evaluated Sorafenib Tosylate (SRT)-loaded polymeric microparticles (MPs) using biodegradable polymer polycaprolactone (PCL) as a potential inhalable carrier for NSCLC. MPs were prepared by spray-drying an oil-in-water (o/w) emulsion. The optimized MPs demonstrated excellent flowability, particle size of 2.84 ± 0.5 μm, zeta potential of -14.0 ± 1.5 mV, and 85.08 ± 5.43% entrapment efficiency. ATR-FTIR/DSC studies revealed a lack of characteristic peaks of the crystalline drug signifying good entrapment of the drug. MPs were spherical and uniform in SEM pictures. The MPs showed a biphasic release pattern up to 72h. The Anderson cascade impactor (ACI) investigation demonstrated the highest drug deposition at stage 4, which revealed that the MPs can reach the lungs' secondary and terminal bronchi. Inhalable MPs had an efficient aerodynamic property with a mass median aerodynamic diameter (MMAD) of 2.63 ± 1.3 μm, a geometric standard deviation (GSD) of 1.93 ± 0.2 μm, and a fine particle fraction (FPF) of 87 ± 2.5%. Finally, in cytotoxicity studies on A549 cancer cells, MPs had an IC50 value of 0.6011 ± 0.8 μM, which was 85.68% lower than free drug. These findings suggest SRT-loaded inhalable PCL-based MPs as a novel NSCLC treatment.

Synthesis and biological evaluation of diaryl urea derivatives designed as potential anticarcinoma agents using de novo structure-based lead optimization approach

To develop inhibitors blocking VEGFR2 and the Raf/MEK/ERK mitogen-activated protein kinase signaling pathway new compounds based on sorafenib were designed, synthesized and biologically evaluated. Using de novo design method, a library of new ligands was generated and expanded. Considering in silico binding affinity towards VEGFR2, synthetic feasibility, and drug-likeness property, some of the designed ligands were selected for synthesis and screening for their in vitro antiproliferative activities against two cancer cell lines (HT-29 and A549). Four compounds (13a, 14a, 14l and 15b) exhibited stronger antiproliferative activity (with IC₅₀ values of 13.27, 6.62, 12.74, 3.38 μM, respectively) against HT-29 cells compared to that of the positive reference drug sorafenib (IC₅₀ = 17.28 μM). Notably, compound 15b demonstrated the highest activity, and in particular, it induced HT-29 apoptosis, increased intracellular reactive oxygen species level, arrested cell cycle at G0/G1 phase, and influenced the expression of apoptosis- and cell cycle-related proteins. 15b compound can effectively block the Raf/MEK/ERK pathway and inhibit VEGFR2 phosphorylation. Molecular docking revealed that 15b can bind well to the active site of VEGFR2 receptor. Collectively, 15b may be considered as a promising compound amenable for further investigation for the development of new anticancer agents.

Sorafenib Loaded Inhalable Polymeric Nanocarriers against Non-Small Cell Lung Cancer

PURPOSE

This exploration is aimed at developing sorafenib (SF)-loaded cationically-modified polymeric nanoparticles (NPs) as inhalable carriers for improving the therapeutic efficacy of SF against non-small cell lung cancer (NSCLC).

METHODS

The NPs were prepared using a solvent evaporation technique while incorporating cationic agents. The optimized NPs were characterized by various physicochemical parameters and evaluated for their aerosolization properties. Several in-vitro evaluation studies were performed to determine the efficacy of our delivery carriers against NSCLC cells.

RESULTS

Optimized nanoparticles exhibited an entrapment efficiency of ~40%, <200 nm particle size and a narrow poly-dispersity index. Cationically-modified nanoparticles exhibited enhanced cellular internalization and cytotoxicity (~5-fold IC₅₀ reduction vs SF) in various lung cancer cell types. The inhalable nanoparticles displayed efficient aerodynamic properties (MMAD ~ 4 μM and FPF >80%). In-vitro evaluation also resulted in a superior ability to inhibit cancer metastasis. 3D-tumor simulation studies further established the anti-cancer efficacy of NPs as compared to just SF.

CONCLUSION

The localized delivery of SF-loaded nanoparticles resulted in improved anti-tumor activity as compared to SF alone. Therefore, this strategy displays great potential as a novel treatment approach against certain lung cancers.

Autophagic cell death associated to Sorafenib in renal cell carcinoma is mediated through Akt inhibition in an ERK1/2 independent fashion

OBJECTIVES

To fully clarify the role of Mitogen Activated Protein Kinase in the therapeutic response to Sorafenib in Renal Cell Carcinoma as well as the cell death mechanism associated to this kinase inhibitor, we have evaluated the implication of several Mitogen Activated Protein Kinases in Renal Cell Carcinoma-derived cell lines.

MATERIALS AND METHODS

An experimental model of Renal Cell Carcinoma-derived cell lines (ACHN and 786-O cells) was evaluated in terms of viability by MTT assay, induction of apoptosis by caspase 3/7 activity, autophagy induction by LC3 lipidation, and p62 degradation and kinase activity using phospho-targeted antibodies. Knock down of ATG5 and ERK5 was performed using lentiviral vector coding specific shRNA.

RESULTS

Our data discard Extracellular Regulated Kinase 1/2 and 5 as well as p38 Mitogen Activated Protein Kinase pathways as mediators of Sorafenib toxic effect but instead indicate that the inhibitory effect is exerted through the PI3K/Akt signalling pathway. Furthermore, we demonstrate that inhibition of Akt mediates cell death associated to Sorafenib without caspase activation, and this is consistent with the induction of autophagy, as indicated by the use of pharmacological and genetic approaches.

CONCLUSION

The present report demonstrates that Sorafenib exerts its toxic effect through the induction of autophagy in an Akt-dependent fashion without the implication of Mitogen Activated Protein Kinase. Therefore, our data discard the use of inhibitors of the RAF-MEK-ERK1/2 signalling pathway in RCC and support the use of pro-autophagic compounds, opening new therapeutic opportunities for Renal Cell Carcinoma.