Luminescent core–shell Ca2MoO5:Eu3+-MCM-41 structure for sustained drug release

The spherical mesoporous MCM-41 coated with a novel Ca₂MoO₅:Eu³⁺ phosphor layer was prepared for the first time. The obtained Ca₂MoO₅:Eu³⁺-MCM-41 was characterized via XRD and FT-IR. The crystal system of the Ca₂MoO₅ phase was determined to be orthorhombic, and its space group was found to be Ima2 (46), and its cell parameters were a = 16.175, b = 5.1514, c = 5.6977 A°; α = β = γ = 90°. The particle dimensions of MCM-41 and Ca₂MoO₅:Eu³⁺-MCM-41 nanoparticles were determined to be 260 nm and 229 nm via scanning electron microscopy analysis. Bortezomib was loaded into the Ca₂MoO₅:Eu³⁺-MCM-41 nanoparticles under scCO₂ at 200 bars and 40 °C. The results of the TG analysis showed that the amount of drug-loaded to MCM-41 and Ca₂MoO₅:Eu³⁺-MCM-41 nanoparticles were determined to be 14.02% and 3.02%, respectively. The BET analysis showed that while the specific surface area and pore volume of MCM-41 and Ca₂MoO₅:Eu³⁺ before Bortezomib (BTZ) loading were 1,506 m²/g and 267 m²/g, respectively, after drug loading these values were found to decrease to 488 m²/g and 7.883 m²/g. It was determined that BTZ was released from the nanoparticles in a sustained manner over 66 h. The R² value, which was calculated to be 0.9739, indicated that the release kinetic of BTZ followed the Korsmeyer–Peppas model.     

Combined RNA-expression and 2D-PAGE-screening identifies comprehensive interaction networks affected after bortezomib or enzastaurin exposure of mantle cell lymphoma

Despite recent advances in treatment, mantle cell lymphoma (MCL) still represents a disease with dismal prognosis due to its progressive clinical course, high rate of therapy refractory cases and frequent relapses. During recent years, the proteasome inhibitor bortezomib and enzastaurin, an inhibitor of protein kinase c have been explored in MCL. In relapsed disease enzastaurin achieved disease stabilization in a subset of patients. Bortezomib in relapsed and refractory MCL achieves response rates of 30-40%. To identify signal pathways and manifold interactions regulating cellular response to molecular targeted approaches several high throughput screening methods were applied. A combined network analysis of the identified target molecules based on both RNA array expression data and a survey of cellular protein levels resulted in a unified interaction network more comprehensive (bortezomib: 394 and enzastaurin: 174 molecules) than the networks of the individual screening techniques (329/44 and 117/36 molecules respectively). Interestingly, although none of the target molecules were matched in both RNA-expression and protein level analysis they were mapped nonetheless to common pathways. Additionally, the ranking of identified pathways allowed an improved characterization of the observed induction of cell apoptosis.     

A convergent approach to synthesis of bortezomib: the use of TBTU suppresses racemization in the fragment condensation

Bortezomib is a first-in-class therapeutic antineoplastic agent used for treating patients with multiple myeloma and mantle cell lymphoma. In this paper we report an improved method for synthesis of the title compound using a convergent approach. TBTU was found to efficiently suppress racemization in the fragment condensation. In comparison with the original synthesis, the presented one is shorter by two steps, higher in yield, and provides better atom economy.     

Proteasome Inhibitor Anticancer Drug Bortezomib Redox Behaviour at a Glassy Carbon Electrode

Bortezomib is the first therapeutic proteasome inhibitor used for cancer treatment. The redox behaviour of bortezomib was investigated over a wide pH range. Bortezomib undergoes electrochemical oxidation and reduction in independent mechanisms. The oxidation of bortezomib is pH‐dependent for pH<7.5 and occurs with the transfer of one electron and one proton involving the formation of two electroactive oxidation products. The reduction of bortezomib is quasi‐reversible, pH‐dependent, involving the transfer of two electrons and two protons and does not involve the formation of electroactive products. The value of pK_a≈7.5 was determined. Mechanisms for oxidation and reduction were proposed.