NavitoclaxisapotentandorallybioavailableBcl-2familyproteininhibitorthatbindswithhighaffinity(K_i<1=""nm)=""to=""multiple=""anti-apoptotic=""bcl-2=""family=""proteins=""including="">_L,Bcl-2andBcl-w.

Ki:<1=""nm="">_L),<1=""nm=""(bcl-2),=""><1=""nm="">

Navitoclax(ABT-263)isactiveagainstapproximatelyone-halfofthecelllinesofthePPTPinvitropanel.ThemedianIC₅₀ forallofthelinesinthepanelis1.91µM^[1].Navitoclaxincombinationwithchemotherapyagentsleadsmostovariancancercelllinesasynergisticresponse,andenhancesthecaspaseactivationatallpaclitaxeldosestestedinbothSK-OV-3andIGROV-1celllines^[2].

Navitoclax(100mg/kg/day,p.o.)alsoimprovesresponsestobendamustine-rituximab(BR)inasubsetoftumoursinmicexenograft^[3].

• [1].LockR1,etal.Initialtesting(stage1)oftheBH3mimeticABT-263bythepediatricpreclinicaltestingprogram.PediatrBloodCancer.2008Jun;50(6):1181-1189.

  [2].WongM,etal.Navitoclax(ABT-263)reducesBcl-x(L)-mediatedchemoresistanceinovariancancermodels.MolCancerTher.2012Apr;11(4):1026-1035.

  [3].AcklerS,etal.Navitoclax(ABT263)andBendamustine±RituximabInduceEnhancedKillingofNon-Hodgkin"sLymphomaTumorsinVivo.BrJPharmacol.2012Oct;167(4):881-891.

Tomeasurecaspase-3/7activation,IGROV-1andSKOV3cellsareseededin96-wellplatesat5,000cellsperwell.After24hours,cellsaretreatedwithnavitoclax(1μM),paclitaxel(doserange=1-100nM),orincombinationwithnavitoclaxandpaclitaxelusingthesamedosingconcentrations.Eachtreatmentisdoneinduplicatewells.Inductionofapoptosis,followingtreatmentattime0,4,24,and48hours,isdeterminedusingaCaspase-Glo3/7assay.ADMSOcontrolisincludedinallstudies.Theexperimentisconductedtwice,andthedataarepresentedasanaverageofbothruns.MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly.

NavitoclaxisdissolvedinDMSO.

Cellsareseededin384-wellplatesat3,000cellsperwell.After24hours,cellsaretreatedwithnavitoclax(doserangeof14nM-3.3μM)andpaclitaxel(doserangeof15pM-100nM)orgemcitABIne(doserangeof0.5nM-3.3μM)ina9by7matrix.Eachtreatmentiscarriedoutinquadruplicate.Cellsaretreatedfor72hours,andcellviabilityisdeterminedusingtheCellTiter-Gloassay.CellviabilityforeachtreatmentisnormalizedagainsttheDMSOcontrolgroup. MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly.

NavitoclaxisadministeredbyoralgavageoncedailyinamixtureofPhosal50PG:PEG400:ethanol.

ForsystemicGranta519tumourmodels,2×10⁶cellsareinjectedviathetailveinin0.1mLvolumeofcellmediumonday0,andtreatmentisinitiatedonday14.Allanimalsareear-taggedandmonitoredindividuallythroughouttheexperiment.NavitoclaxisadministeredbyoralgavageoncedailyinamixtureofPhosal50PG:PEG400:ethanol.Bendamustineandrituximabareadministeredi.v.at25and10mg/kg,respectively,onday1.Navitoclaxisadministeredapproximately2hbeforebendamustineandrituximab.Alltrialsarecomprisedof10micepergroup.Micearehumanelykilledwhentumoursreachedasize>2000mm³ orwhenanysignsofdistressaremonitored.Signsofdistressincludelossofambulation,labouredbreathingorweightloss>20%meanbodyweightpercage.MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly.

• [1].LockR1,etal.Initialtesting(stage1)oftheBH3mimeticABT-263bythepediatricpreclinicaltestingprogram.PediatrBloodCancer.2008Jun;50(6):1181-1189.

  [2].WongM,etal.Navitoclax(ABT-263)reducesBcl-x(L)-mediatedchemoresistanceinovariancancermodels.MolCancerTher.2012Apr;11(4):1026-1035.

  [3].AcklerS,etal.Navitoclax(ABT263)andBendamustine±RituximabInduceEnhancedKillingofNon-Hodgkin"sLymphomaTumorsinVivo.BrJPharmacol.2012Oct;167(4):881-891.

974.61

C₄₇H₅₅ClF₃N₅O₆S₃

923564-51-6

RoomtemperatureincontinentalUS;mayvaryelsewhere

10mMinDMSO

*"<1 mg/ml"="" means="" slightly="" soluble="" or="" insoluble.="" "≥"="" means="" soluble,="" but="" saturation="">