Cell lines

RPMI 8226 and U266 human multiple myeloma cells

Preparation method

The solubility of this compound in DMSO is >13.2mg/mL. General tips for obtaining a higher concentration: Please warm the tube at 37℃ for 10 minutes and/or shake it in the ultrasonic bath for a while. Stock solution can be stored below -20℃ for several months.

Reacting condition

1.25-20μmol/L for 90 minutes

Applications

In RPMI 8226 and U266 human multiple myeloma cells, TNF-α (tumor necrosis factor-a)-induced phosphorylation and degradation of IκBα were completely abrogated by MLN120B in a dose dependent fashion. Phosphorylation of p65 NF-κB (Nuclear factor-κB) induced by TNF-α was also blocked by MLN120B. Importantly, MLN120B inhibited both IL-6 secretion from BMSCs (bone marrow stromal cells) triggered by multiple myeloma cell adhesion and proliferation of multiple myeloma cells adherent to BMSCs. MLN120B triggered 25% to 90% growth inhibition in a dose-dependent fashion in multiple myeloma cell lines, which is not overcome by growth and antiapoptotic factors (IL-6 or IGF-I).

Animal models

Rat adjuvant-induced arthritis model (Two-month-old female Lewis rats)

Dosage form

orally as a suspension delivered via a gavage needle, at 30 mg/kg, 10 mg/kg, 3 mg/kg

Application

In Lewis rats, Animals receiving MLN120B showed a dose-dependent reduction of arthritis development, as measured by paw swelling, compared with vehicle-treated controls. Administration of MLN120B at a dosage of 30 mg/kg twice daily offered significant protection against weight loss compared with arthritic controls. These results indicated bone and cartilage destruction and pannus development were the features most improved with MLN120B administration.

Other notes

Please test the solubility of all compounds indoor, and the actual solubility may slightly differ with the theoretical value. This is caused by an experimental system error and it is normal.

MLN120B is a potent and effective inhibitor of IκB kinase beta subunit (IKKβ) with IC50 value of 20 μM [1].

IKK is an enzyme complex which is a part of the upstream of NF-κB signal transduction cascade. It is composed of three subunits, including IKKα, IKKβ and IKKγ. The IKKβ subunit is able to phosphorylate IκBα protein. Normally, IκBα protein inactivate NF-κB transcription factors and keep them sequestering in inactive state in the cytoplasm. However, once IκBα protein is phosphorylated by IKKβ subunit, the IκBα protein will be dissociated from NF-κB transcription factor and thus remove the inactivation effect. Therefore, the transcription of NF-κB will be activated. This signaling pathway is involved in many immune and inflammatory processes.

In multiple myeloma cell line RPMI 8226 and INA 6, treatment of MLN120B resulted in the dose-dependent inhibition of IKKβ-induced IκBα protein phosphorylation and subsequent NF-κB activation. Additionally, it was observed that MLN120B was able to block TNF-α-induced NF-κB activation in MM.1S cell line. These observations suggested the inhibitory action of MLN120B on IKKβ. [1].

In mouse model, polyarthritis was introduced in footpads, where IKKβ-induced NF-κB activation might result in a serial of advert effects. Oral administration of MLN120B (12 mg/kg twice daily) inhibited paw swelling in a dose-dependent manner, and offered protection against arthritis-induced weight loss. Therefore, it could be implied that MLN120B was able to inhibit IKKβ-induced NF-κB activation [2].

References:
[1].  Hideshima T, Neri P, Tassone P. MLN120B, a novel IkappaB kinase beta inhibitor, blocks multiple myeloma cell growth in vitro and in vivo. Clin Cancer Res. 2006, 12(19): 5887-5894.
[2].  Schopf L, Savinainen A, Anderson K. IKKbeta inhibition protects against bone and cartilage destruction in a rat model of rheumatoid arthritis. Arthritis Rheum. 2006, 54(10): 3163-3173.