OSI-420

 

Distributor Tel: +886-2-2827-1197jimmy@new.abscience.com.tw

Biological Activity

Description	OSI-420 is the active metabolite of Erlotinib (EGFR inhibitor with IC50 of 2 nM).
Targets	EGFR
IC50	2 nM [1]
In vitro	OSI-420 is the major metabolite of Erlotinib in human plasma. Erlotinib disappearance from plasma after a short IV infusion is biexponential with a mean terminal half-life of 5.2 h and a mean clearance of 128 ml/min per m(2). OSI-420 exposure (AUC) in plasma is 30% (range 12-59%) of erlotinib, and OSI-420 clearance is more than 5-fold higher than erlotinib. Erlotinib and OSI-420 are equipotent, and the combined concentrations of erlotinib + OSI-420 achieved in the CSF exceeded the IC50 (7.9 ng/ml or 20 nM) for the EGFR tyrosine kinase inhibition in intact tumor cells. [1] Erlotinib potently inhibits EGFR activation in intact cells including HNS human head and neck tumor cells (IC50 20nM), DiFi humancolon cancer cells andMDA MB-468 human breast cancer cells. Erlotinib (1 μM) induces apoptosis in DiFi humancolon cancer cells. [2] Erlotinib growth of a panel of NSCLC cell lines including A549, H322, H3255, H358 H661, H1650, H1975, H1299, H596 with IC50 ranging from 29 nM to >20 μM. [3] Erlotinib(2 μM) significantly inhibits growth of AsPC-1 and BxPC-3 pancreatic cells. [4]The effects of Erlotinib HCl in combination with gemcitabine are considered additive in KRAS-mutated pancreatic cancer cells. Ten micromolar of Erlotinib inhibits EGFR phospho-rylation at the Y845 (Src-dependent phosphorylation) and Y1068 (auto-phosphorylation) sites. [5] Combination with Erlotinib could down-modulate rapamycin-stimulated Akt activity and produces a synergistic effect on cell growth inhibition. [6]
In vivo	At doses of 100 mg/kg, Erlotinib completely prevents EGF-induced autophosphorylation of EGFR in human HN5 tumors growing as xenografts in athymic mice and of the hepatic EGFR of the treated mice. [1] Erlotinib reduces the growth of xenografted human AML cells. [4]
Features	OSI 420 is a major active metabolite of Erlotinib.

Protocol(Only for Reference)

Kinase Assay: ^[1]

Kinase Assays

96-well plates are coated by incubation overnight at 37 °C with 100 μL per well of 0.25 mg/mL PGT in PBS. Excess PGT is removed by aspiration, and the plate is washed 3 times with washing buffer (0.1% Tween 20 in PBS). The kinase reaction is performed in 50 μL of 50 mM HEPES (pH 7.3), containing 125 mM sodium chloride, 24 mM magnesium chloride, 0.1 mM sodium orthovanadate, 20 μM ATP, 1.6 μg/mL EGF, and 15 ng of EGFR, affinity purified from A431 cell membranes. Erlotinib HCl in DMSO is added to give a final DMSO concentration of 2.5%. Phosphorylation is initiated by addition of ATP and proceeded for 8 minutes at room temperature, with constant shaking. The kinase reaction is terminated by aspiration of the reaction mixture and is washed 4 times with washing buffer. Phosphorylated PGT is measured by 25 minutes of incubation with 50 μL per well HRP-conjugated PY54 antiphosphotyrosine antibody, diluted to 0.2 μg/mL in blocking buffer (3% BSA and 0.05% Tween 20 in PBS). Antibody is removed by aspiration, and the plate is washed 4 times with washing buffer. The colonmetric signal is developed by addition of TMB Microwell Peroxidase Substrate, 50μL per well, and stopped by the addition of 0.09 M sulfuric acid, 50 μL per well. Phosphotyrosine is estimated by measurement of absorbance at 450 nm. The signal for controls is typically 0.6-1.2 absorbance units, with essentially no back ground in wells without AlP, EGFR, or PGT and is proportional to the time of incubation for 10 minutes.

Cell Assay: ^[3]

Cell lines	A549, H322, H3255, H358 H661, H1650, H1975, H1299, H596 cells
Concentrations	30 nM-20 μM
Incubation Time	72 hour
Method	Exponentially growing cells are seeded in 96-well plastic plates and exposed to serial dilutions of erlotinib, pemetrexed, or the combination at a constant concentration ratio of 4:1 in triplicates for 72 h. Cell viability is assayed by cell count and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Growth inhibition is expressed as the percentage of surviving cells in drug-treated versus PBS-treated control cells (which is considered as 100% viability). The IC50 value is the concentration resulting in 50% cell growth inhibition by a 72-h exposure to drug(s) compared with untreated control cells and is calculated by the CalcuSyn software.

Animal Study: ^[7]

Animal Models	Male 5-week-old BALB-nu/nu with HPAC
Dosages	50 mg/kg
Administration	Oral administration
Solubility	15% Captisol, 30 mg/mL

1

References

Chemical Information

Download OSI-420 SDF

Chemical Name	2-(4-(3-ethynylphenylamino)-7-(2-methoxyethoxy)quinazolin-6-yloxy)ethanol hydrochloride

Preparing Stock Solutions

Stock Solution (1ml DMSO)	1mM	10mM	20mM	30mM
Mass(mg)	0.41587	4.1587	8.3174	12.4761

Customer Reviews (1)

Click to enlarge	Rating
	Source	Sci Pharm, 2012, 80(3), 633-646 . OSI-420 purchased from Selleck
	Method	LC-MS/MS analysis
	Cell Lines	Wistar rats
	Concentrations	1.5-1150 ng/mL
	Incubation Time	24 h, 12h
	Results	An LC-MS/MS bioanalytical method for the simultaneous determination of three analytes, CCB, ERT, and OSI-420, was developed and validated in rat plasma. The method was good enough to detect the low concentration of 1.5 ng/mL for all analytes in 50 µL rat plasma, and can further be improved by increasing the plasma volume.

Product Citations (2)

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  Secretory phospholipase A2-IIa is involved in prostate cancer progression and may potentially serve as a biomarker for prostate cancer. [Dong Z, et al. Carcinogenesis 2010;31(11), 1948-1955]

  
  PubMed: 20837598


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  Simultaneous Determination of Celecoxib, Erlotinib, and its Metabolite Desmethyl-Erlotinib (OSI-420) in Rat Plasma by Liquid chromatography/Tandem Mass Spectrometry with Positive/Negative Ion-Switching Electrospray Ionisation. [Thappali SR, et al. Sci Pharm 2012;80(3):633-46]

  
  PubMed: 23008811