Lapatinib (GW-572016) Ditosylate

 

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

Biological Activity

Description	Lapatinib Ditosylate (GW572016, GW2016) is a potent EGFR and ErbB2 inhibitor with IC50 of 10.8 and 9.2 nM, respectively.
Targets	EGFR	ErbB2
IC50	10.8 nM	9.2 nM [1]
In vitro	Lapatinib Ditosylate weakly inhibits the activity of ErbB4 with IC50 of 367 nM, and displays >300-fold selectivity for EGFR and ErbB2 over other kinases such as c-Src, c-Raf, MEK, ERK, c-Fms, CDK1, CDK2, p38, Tie-2, and VEGFR2. Lapatinib Ditosylate significantly inhibits receptor autophosphorylation of EGFR and ErbB2 in a dose-dependent manner with IC50 of 170 nM and 80 nM, respectively in HN5 cells; as well as 210 nM and 60 nM, respectively in BT474 cells. Unlike OSI-774 and Iressa (ZD1839) which preferentially inhibit the growth of the EGFR-overexpressing cells, Lapatinib Ditosylate inhibits the growth of both EGFR- and ErbB2-overexpressing cells. Lapatinib Ditosylate displays higher inhibitory activity against EGFR- or ErbB2-overexpressing cells with IC50 of 0.09-0.21 μM, compared with cells expressing low levels of EGFR or ErbB2 with IC50 of 3-12 μM, and exhibits ~100-fold selectivity over the normal fibroblast cells. Lapatinib Ditosylate potently inhibits the outgrowth of EGFR-overexpressing HN5 and A-431 cells, as well as ErbB2-overexpressing BT474 and N87 cells, and significantly induces G1 arrest of HN5 cells and apoptosis of BT474 cells, which are associated with inhibition of AKT phosphorylation. [1]
In vivo	Oral administration of Lapatinib Ditosylate (~100 mg/kg) twice daily significantly inhibits the growth of BT474 and HN5 xenografts in a dose-dependent manner. [1]
Features

Protocol(Only for Reference)

Kinase Assay: ^[1]

In vitro kinase assays

The IC50 values for inhibition of enzyme activity are generated by measuring inhibition of phosphorylation of a peptide substrate. The intracellular kinase domains of EGFR and ErbB2 are purified from a baculovirus expression system. EGFR and ErbB2 reactions are performed in 96-well polystyrene round-bottomed plates in a final volume of 45 μL. Reaction mixtures contain 50 mM 4-morpholinepropanesulfonic acid (pH 7.5), 2 mM MnCl2, 10 μM ATP, 1 μCi of [γ33P] ATP/reaction, 50 μM Peptide A [Biotin-(amino hexonoic acid)-EEEEYFELVAKKK-CONH2], 1 mM dithiothreitol, and 1 μL of DMSO containing serial dilutions of Lapatinib beginning at 10 μM. The reaction is initiated by adding the indicated purified type-1 receptor intracellular domain. The amount of enzyme added is 1 pmol/reaction (20 nM). Reactions are terminated after 10 minutes at 23°C by adding 45 μL of 0.5% phosphoric acid in water. The terminated reaction mix (75 μL) is transferred to phosphocellulose filter plates. The plates are filtered and washed three times with 200 μL of 0.5% phosphoric acid. Scintillation cocktail (50 μL) is added to each well, and the assay is quantified by counting in a Packard Topcount. IC50 values are generated from 10-point dose-response curves.

Cell Assay: ^[1]

Cell lines	HFF, MCF-7, T47D, A-431, HN5, BT474, N87, CaLu-3, HB4a, and HB4a c5.2
Concentrations	Dissolved in DMSO, final concentrations ~100 μM
Incubation Time	72 hours
Method	Cells are exposed to various concentrations of Lapatinib for 72 hours. Relative cell number is estimated using methylene blue staining. The absorbance at 620 nm is read in a Spectra microplate reader. Cell death and cell cycle analysis are assessed by propidium iodide staining and antibody detection of incorporated BrdUrd and staining with propidium iodide.

Animal Study: ^[1]

Animal Models	CD-1 nude female mice implanted s.c. with HN5 cells, and C.B-17 SCID female mice implanted s.c. with BT474 cells
Dosages	~100 mg/kg
Administration	Orally twice daily
Solubility	15% Captisol, 5 mg/mL

1

References

Clinical Trial Information( data from http://clinicaltrials.gov)

NCT Number	Recruitment	Conditions	Sponsor /Collaborators	Start Date	Phases
NCT01705340	Terminated	Adenocarcinoma of the Gastroesophageal Junction|HER2-positive Breast Cancer|Male Breast Cancer|Recurrent Breast Cancer|Recurrent Esophageal Cancer|Recurrent Gastric Cancer|Stage IIIC Breast Cancer|Sta	National Cancer Institute (NCI)	2012-09	Phase 1
NCT01783756	Recruiting	Central Nervous System Metastases|HER2-positive Breast Cancer|Male Breast Cancer|Recurrent Breast Cancer|Stage IV Breast Cancer	Jonsson Comprehensive Cancer Center	2013-06	Phase 1|Phase 2
NCT01868503	Recruiting	Male Breast Cancer|Recurrent Breast Cancer|Stage IIIA Breast Cancer|Stage IIIB Breast Cancer|Stage IIIC Breast Cancer	Stanford University|National Cancer Institute (NCI)	2013-07	Phase 2
NCT01873833	Recruiting	HER2-positive Breast Cancer|Recurrent Breast Cancer|Stage IV Breast Cancer	USC/Norris Comprehensive Cancer Center|National Cancer Institute (NCI)	2013-07	Phase 2
NCT01947023	Recruiting	Recurrent Thyroid Cancer	National Cancer Institute (NCI)	2013-08	Phase 1

Chemical Information

Download Lapatinib (GW-572016) Ditosylate SDF

Chemical Name	N-(4-(3-fluorobenzyloxy)-3-chlorophenyl)-6-(5-((2-(methylsulfonyl)ethylamino)methyl)furan-2-yl)quinazolin-4-amine,di4-methylbenzenesulfonate

Preparing Stock Solutions

Stock Solution (1ml DMSO)	1mM	10mM	20mM	30mM
Mass(mg)	0.92546	9.2546	18.5092	27.7638

Customer Reviews (7)

Click to enlarge	Rating
	Source	Int J Proteomics 2011 2011, Article ID 215496. Lapatinib (GW-572016) Ditosylate purchased from Selleck
	Method	CEER assay
	Cell Lines	H1734 cell line
	Concentrations	0-10 μM
	Incubation Time	4 h
	Results	HER1 and/or HER2 pathway-activated cell lines, H1734 , had their activation blocked by the HER1/2 kinase inhibitors Lapatinib.

Product Citations (13)

• 
  

  ErbB receptor tyrosine kinase/NF-κB signaling controls mammosphere formation in human breast cancer. [Hinohara K, et al. Proc Natl Acad Sci U S A 2012;109(17):6584-9]

  
  PubMed: 22492965


• 
  

  Azacytidine and erlotinib exert synergistic effects against acute myeloid leukemia. [Lainey E, et al. Oncogene 2012;32(37):4331-42]

  
  PubMed: 23085751


• 
  

  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):1948-55]

  
  PubMed: 20837598