Presentation on theme: "DOM Grand Rounds--2013 The Therapeutic Implications of EML4/ALK, ROS-1 and Other New Biomarkers Lyudmila Bazhenova, MD Associate Clinical Professor Lung."— Presentation transcript:
1DOM Grand Rounds--2013The Therapeutic Implications of EML4/ALK, ROS-1 and Other New BiomarkersLyudmila Bazhenova, MDAssociate Clinical ProfessorLung Cancer Unit LeaderUC San Diego Moores Cancer Center
2Objectives Review current state of targetable lung cancer biomarkers Review and contrast clinical characteristics of patients with EML4-ALK, ROS 1, and KIFB5-RET fusion protein, testing strategies and agents with clinical activity.
4Mechanism of Action of ALK, ROS1 and RET Fusion Oncogenes All three are receptor tyrosine kinases (RTK)ALK and RET are capable of homodimerization and self (ligant independend) activationMechanism of self activation of ROS1 is being debatedDownstream signaling via RAS/ERK (proliferation), and PI3K/AKT and JAK/STAT( resistance to apoptosis)Some prefer one pathways over another
5Testing for Fusion Oncogenes IHC expressionBreak apart FISHAmount of protein on the surface of the cellRT-PCR
7ALK Fusion Gene Echinoderm microtubule associated protein-like 4 ? N C anaplastic lymphoma kinaseAdapted from Soda et al. Nature; 2007.
8ALK Fusion VariantsSasaki, European Journal of Cancer; 2010.
9Methods of ALK Detection FISH break apartPros: independent of FPECons: if inversion involves a small locus of 2p it could be false negative; can not distinguish variants; cut of is 15% of nuclei with split signal; low throughputRT-PCRPros: Rapid detection and identification of each unique variantCons: False negatives; Loss of RNA during de parafinization; has to be multiplexed, i.e probes to all known variants. Unknown variants will not be detected.IHCPros: easyCons: several antibodies have been developed which look promising as a screening tool. No commercially available IHC in the US.VENTANA just received an approval in China with 93% concordance with FISH, sensitivity 100%, specificity 98%
10Frequency: 4% in all, 33% in EGFR negative never smokers EML4-ALK FusionPatients: younger, non smokers, with adenocarcinoma, adenosquamous carcinoma and rarely SCCFrequency: 4% in all, 33% in EGFR negative never smokersBiology: 16 EML4-ALK variants have been identified in NSCLC. Clinical significance of each variant is unknown.Testing: Visys break apart FISH (> 15% cells with split signal in 50 nuclei scored).ALK PCR, IHCTherapy: crizotinibb, Fusion of the N-terminal portion of EML4 (comprising the basic region, the HELP domain and part of the WD-repeat region) to the intracellular region of ALK (containing the tyrosine kinase domain). TM, trans membrane domain.c, Both the ALK gene and the EML4 gene map to chromosome 2p, but have opposite orientations. In the NSCLC patient 33, EML4 is disrupted at a position 3.6 kb downstream of exon 13 and is ligated to a position 297 bp upstream of exon 21 of ALK, giving rise to the EML4–ALK (variant 1) fusion gene (left panel). Filled and open horizontal arrows indicate the direction of transcription and the positions of the Fusion-genome primers, respectivelyIdentification of EML4–ALKTo isolate novel transforming genes in NSCLC, we generated a retroviral cDNA expression libraryIn vitro difeerent variants of alk has different stability and responsiveness to ALK inhibitor and HSP 9- inhibitors.1Shaw AT, ASCO; 2010;2Kris MG. ASCO 2011; abstract CRA7506.3Rodig SJ, Clin Cancer Res; 2009;15Soda M, et al. Nature; 2007;448
11Clinical Efficacy of Crizotinib Some degree of tumor shrinkage 90%ORR %DCR % at week 8Median time to response 7.9 weeks ( weeks)Median response duration 49.1 weeksMedian PFS 9.7 months (95% CI 7∙7–12∙8)N=149Best % change.Unknown…How crizotinib compares to chemotherapy 1st lineQOLOSTTPCamidge, Lancet oncology 13, 2012
121st Line or Second LineNo studies examining the best placement of the drug.FDA approved the drug without mentioning the line of therapy.One can make a leap of faith from EGFR inhibitors and use it in the first line.Profile 1007 compared crizotinib to 2nd line chemotherapyPFS 7.7 m vs. 3 m in favor of crizotinib (HR 0.49; 95% CI, 0.37 to 0.64; P<0.001)RR 65% vs. 20 % in favor of crizotinib ( p<0.001)OS not different, 64% of patients in chemotherapy arm received crizotinibQOL: greater reduction of symptoms and delay in new symptoms on crizotinib arm.Profile 1014 will compare crizotinib to 1st line chemotherapy.Shaw NEJM ;June 2013
15Characteristics of Progression Patients were allowed to stay on the study post progression if they continued to derive clinical benefiMedian duration of treatment 43.1 m (Range )69/149 patients had disease progression at the data cut off.39 continued to receive crizotinib for at least 2 weeks post progression12 of them did that for 6 monthsRange of post progression treatment is 21 to 591 days.Most common new sites of progression were brain ( N=10), lung (n=5), liver ( N=3)Camidge, Lancet oncology 13, 2012.
16Duration of Initial Response and Post Progression Therapy Patients are ordered by initial best response before progression and duration of crizotinib treatment afterprogression (n=39). *Defi ned as the time (in weeks) from the fi rst documentation of objective tumour response(complete response or partial response) that was subsequently confi rmed, to the fi rst documentation ofprogressive disease or death. Stable disease duration was calculated from the date of the fi rst dose to the date offi rst documented disease progression. †Defi ned as time from investigator-documented progressive disease to thelast date of crizotinib dose or censor at the time of analysis. Disease progression and best objective response werederived according to Response Evaluation Criteria in Solid Tumors. ‡Treatment ongoing at the time of analysis.ÅòReceived crizotinib as fi rst-line treatment.
17Crizotinib Resistance L1196ML1152RC1156YF1174LSasaki Clinical Cancer Research. Epub 2011.
18Management of Crizotinib Resistance Local treatment with radiation for locally progressing diseaseClonal evolutionPlatinum based doublet or tripletSecond generation ALK inhibitorsAP26114LDK378CH (RG7853)HSP 90 inhibitors
19Responses to Second Generation Inhibitors in crizotinib Resistant Tumors LDK378( phase I)58% ORR1CNS penetrationCH ( phase I/II)48% ORR2AP26113 ( phase I/II)76% ORR31Shaw. ASCO 2013 abstr 8010.2Gadgeel, World Lung 2013, O16.06.3Camidge. World Lung, MO0706
21Oncogenic ROS1First described fusion gene FIG-ROS1 was found in glioblastoma240kb deletion on 6p21q resulting in a fusion gene coding for oncogenic fusion protein.Short and long isoformsInduce tumorigenesis in xenograft mouse modelsAlso expressed in cholangiocarcinoma in 8.7% and ovarian cancer in 0.5%, gastric and colon, myofibroblastic tumors and angiosarcomaEZR–ROS1 fusion gene has been shown to promote lung adenocarcinoma when ectopically expressed in lung epitheliumGu TL, PLoS One; 2011.Birch AH, PLoS One; 2011;Lee, Cancer; May 2013Bergethon et al. JCO; 2012 (30)8.
24ROS1 FusionPatients: Younger, never smokers, adenocarcinoma, high grade histologyFrequency: % in allBiology: 9 variants have been identified in NSCLC so farClinical significance is unknown. Mechanism of activation is different.FIG-, CD74-, SCL34A2-, TPM3-, SDC4-, EZR-, LRIG3, KDELR2–, and CCDC6–Testing: Visys break apart FISH (> 15% cells with split signal in 50 nuclei scored)ROS PCR, IHCTherapy: crizotinibSome of theShaw AT, JCO 2012;30:(suppl; abstr 7508)Ou, Exp revi. of anticancer therapy 2012,;12Gu TL, PLoS One. 2011; 6:e15640.Birch AH, PLoS One. 2011; 6:e28250Lee, Cancer May 2013Davis Clin Cancer Res . Sep 2012Bergeron, JCO, 30, 2012
25Methods of ROS1 Detection RT-PCRCons: False negatives; 9 variants have been described in a matter of 12 months. Has to be multiplexed, i.e., probes to all known variants. Unknown variants will not be detected.FISH break apartCons: if inversion involves a small locus it could be false negative; can not distinguish variants; cut of is 15% of nuclei with split signal; low throughputIHCCons: not commercially available, several antibodies appear promising
26Response of a ROS1 Positive Patient to Crizotinib 49% homology in the TK domain and ATP binding siteCrizotinib is active in ROS1 fused cell culturesBaseline12 weeksBergeron, JCO, 30, 2012.
27Clinical Validation of ROS1 as a Therapeutic Target 14 patients enrolled in phase I studySafety/efficacy of crizotinib 250mg bidROS1 rearrangement by FISHNegative for ALK rearrangementAverage 54 yo, 13/14 never smokers80% received prior therapy8/14 responded (57%)Shaw et al. JCO , 30 (suppl; abstr 7508.)
29Methods of RET Detection RT-PCRCons: False negatives; 3 variants have been described in a matter of 12 months. Has to be multiplexed, i.e probes to all known variants. Unknown variants will not be detected.FISH break apartCons: if inversion involves a small locus it could be false negative; can not distinguish variants; cut of is 15% of nuclei with split signal; not widely available; low throughputIHCCurrent IHC antibodies do not correlate with RET fusionWas originally described in thyroid carcinomas.
31RET FusionPatients: AdenoCA and adenoSCC carcinoma, never or former smokers, poor differentiation ?, earlier LN metastasesFrequency:1.4% in all,5.6 % in “triple negative”( EGFR, ALK, KRAS)6.3% in non smokers negative for EGFR, KRAS, ALK, HER2, BRAF, and ROS116% in non smokers negative for EGFR, KRAS, ALK, ROS1, NRAS, BRAF, HER2, PIK3CA, MEK1, and AKTBiology: 4 variants have been identified in NSCLC so farClinical significance is unknown.KIF5B-, CCDC6-, NCOA4-. TRIM33kinesin family 5B geneSome studies did not show that differentiation is different.Ponatinib is also a RET inhibitorDrilon A, Wang L, Hasanovic A et al. Response to cabozantinib in patientswith RET fusion-positive lung adenocarcinomas. Cancer Discov 2013 (Jun);Ju YS, Genome Res, Drilon, Cancer Discover March 2013Wang R, J Clin Oncol 30: Kohno, Cancer Science Aug 2013
32RET Fusion GeneTesting: Visys break apart FISH (> 15% cells with split signal in 50 nuclei scored)RET PCRTherapy: UnknownSunitinib, Sorafenib, Vandetanib, Carbozatinib, Ponatinib, and Lenvatinib all have potential for activityAll active in KIF5B-RET–transformed cell linesLast 4 are in formal clinical trials
33Clinical Activity of Carbozatinib in RET Fused Patients Drilon A, Wang L, Hasanovic A et al. Response to cabozantinib in patientswith RET fusion-positive lung adenocarcinomas. Cancer Discov 2013 (Jun);4 weeks4 weeks4 weeksDrilon, Cancer Discover March 2013.
34Summary ALK ROS RET Discovery 2007 2012 Type of the product Receptor tyrosine kinaseFrequency4%1.7%1.4%HistologyAdenoCA, AdenoSCC,SCCAdenoCAPoorly differentiatedAdenoSCCPoorly differentiated?Other characteristicsNever smokers, youngerApproved agentCrizotinibNoneAgent in considerationSunitinibSorafenibCarbozatinibVandetanibPonatinibLenvatinib
35HER 2 Insertions Patients: Adenocarcinomas, never smokers Frequency: Incidence %Biology:In-frame insertions into exon 20. Transgenic mouse models confirm oncogenicityTherapy:Drugs of interest: neratinib, afatinib, dacomitinibPreclinical models show synergy with mTOR inhibitors.Clinical trial of neratinib + temsirolimus ongoing, several PR are reportedBoth afatinib and dacomitinib have case reports of responses
36BRAF Mutations Patients: smokers and non smokers Frequency: 1.6-3% Biology: majority of the mutations are non V600E (more likely in smokers), V600E ( more likely in never smokers)Therapy:One case report or a NSCLC patient with V600E patient responding to vemurafenibDabrafenib is being tested in patients with V600E NSCLCMEK inhibitors are being considered for non V600E patients