Anaplastic Lymphoma Kinase Positive Non-small Cell Lung Cancer Patients Research Articles

Early Onset Pulmonary Events and Management Strategies during the Treatment of ALK Positive NSCLC Patients with Brigatinib

Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase and its rearrangements occur in non-small cell lung cancer (NSCLC), resulting in signal dysregulation in kinase domain. As a new generation of potent ALK tyrosine kinase inhibitors (TKIs), Brigatinib was approved in China in March 2022 as a treatment for locally advanced or metastatic NSCLC patients with ALK rearrangement positive. Brigatinib significantly improved the survival, cranial efficacy and quality of life compared to Crizotinib in clinical trials. Brigatinib is generally well tolerated. Brigatinib has been one of the preferred treatments and an addition of options in ALK-rearranged NSCLC. Pulmonary toxicity is one of the adverse effects observed during the treatment of TKIs and deserves the intense attention of clinicians, despite of its low incidence rate. Pulmonary toxicity reported during the treatment of Brigatinib has shown distinct clinical presentations, such as early-onset (median time to onset, 2 days) and rapid tolerance and reversibility of symptoms. In view of this, the concept of early-onset pulmonary events (EOPEs) was proposed and established during the submission for regulatory review and approval. We focused on clinical characteristics, potential mechanism of etiology, and management strategies of EOPEs to provide clinicians evidence for better clinical decision support. .

Short communication: The activity of brigatinib in patients with disease progression after next generation anaplastic lymphoma tyrosine kinase inhibitors and an exploratory analysis of circulating tumor DNA

BackgroundBrigatinib, a second generation anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor (TKI), is central nervous system (CNS) penetrant and active against anaplastic lymphoma kinase (ALK) resistance mutations. We prospectively studied the activity of brigatinib in patients with disease progression after second generation ALK TKIs. MethodsPatients with stage IIIB/IV ALK + non-small cell lung cancer (NSCLC), and progressive disease after second ALK TKIs were eligible. Cohort A enrolled patients with disease progression on any second ALK TKI, cohort B enrolled patients with disease progression after first-line therapy with alectinib, and cohort C enrolled patients who experienced disease progression on standard dose brigatinib. Brigatinib treatment was 90 mg daily for seven days and then escalated to 180 mg daily in cohorts A and B, and 240 mg daily in cohort C. The primary endpoint was objective response rate (ORR), and a 2-stage design was used. The intended enrollment was 20 patients in stage 1, and 20 patients in stage 2. ResultsThe study was closed due to slow accrual. Between March 2017 and June 2020, 32 patients received study therapy; three patients in cohort A moved to cohort C after initial progression for a total of 35 study subjects. Of the 32 patients, 16 (50%) were male, the median age was 55 years (range 32–76), and patients received a median number of 2 prior ALK TKI’s (range 1–3). Cohort A enrolled 27 patients, cohort B enrolled four patients, and cohort C enrolled four patients. The ORR in cohorts A, B, and C was 33% (95% confidence interval (CI: 16% to 54%), 25% (95% CI: 0.63% to 81%), and 0%, respectively. ConclusionBrigatinib has activity in ALK positive NSCLC patients with disease progression after second generation ALK TKIs.

The Genomic Characteristics of ALK Fusion Positive Tumors in Chinese NSCLC Patients.

Anaplastic lymphoma kinase (ALK) fusion events account for ~3–7% genetic alterations in patients with non-small cell lung cancer (NSCLC). In this study, we identified the ALK fusion patterns and a novel ALK fusion partner in 44 ALK positive NSCLC patients using a customized HapOncoCDx panel, and identified ALK fusion partners. The most common partner is EML4, forming the variant 1 (v1, E13:A20, 18/44), variant 2 (v2, E20:A20, 5/44), and variant 3 (v3, E6:A20, 13/44). Moreover, we detected a new ALK fusion partner HMBOX1. At the mutation level, TP53 is the most frequently mutated gene (24%), followed by ALK (12%) and STED2 (12%). The median tumor mutation burden (TMB) of these samples is 2.29 mutations/Mb, ranging from 0.76 mut/Mb to 16.79 muts/Mb. We further elaborately portrayed the TP53 mutation sites on the peptide sequence of the encoded protein by lollipop. The mutational signature and copy number alterations (CNAs) of the samples were also analyzed. The CNA events were found in 13 (13/44) patients, and the most commonly amplified genes were MDM2 (n = 4/13) and TERT (n = 4/13). Together, these results may guide personalized clinical management of patients with ALK fusion in the era of precision medicine.

Clinical utility of liquid biopsy for the diagnosis and monitoring of EML4-ALK NSCLC patients.

Genomic rearrangement in anaplastic lymphoma kinase (ALK) gene occurs in 3-7% of patients with non-small-cell lung cancer (NSCLC). The detection of this alteration is crucial as ALK positive NSCLC patients benefit from ALK inhibitors, which improve both the patient's quality of life and overall survival (OS) compared to traditional chemotherapy. In routine clinical practice, ALK rearrangements are detected using tissue biopsy. Nevertheless, the availability of tumor tissue is compromised in NSCLC patients due to surgical complications or difficult access to the cancer lesion. In addition, DNA quality and heterogeneity may impair tumor biopsies testing. These limitations can be overcome by liquid biopsy, which refers to non-invasive approaches for tumor molecular profiling. In this paper we review currently available technology for non-invasive ALK testing, in NSCLC patients, based on the analysis of circulating tumor DNA (ctDNA), circulating tumor RNA (ctRNA), circulating tumor cells (CTCs), tumor-educated platelets (TEPs) and extracellular vesicles (EVs) such as exosomes. Non-invasive tumor molecular profiling is crucial to improve outcomes and quality of life of NSCLC patients whose tumors harbor a translocation involving ALK locus.

Crizotinib versus chemotherapy: a real-world cost-effectiveness study in China.

Aim: To assess the cost-effectiveness of crizotinib verses platinum-based doublet chemotherapy as the first-line treatment for anaplastic lymphoma kinase (ALK)-positive non-small-cell lung cancer (NSCLC) in the real-world setting. Methods: Data from 163 advanced ALK positive NSCLC patients were collected from West China Hospital, Sichuan University (Chengdu, China). They were categorized into two groups as treated with crizotinib (n=83) or chemotherapy (n=80) as a first-line therapy. The progression-free survival (PFS) as the primary clinical outcome, and the direct medical costs were collected from hospital information systems. Incremental cost-effectiveness ratio (ICER) was calculated with costs, quality-adjusted life-years, as well as the costs discounted at 3% annually. Additionally, two different kinds of medical insurance (MI) for pharma-economic assessment were considered. Results: Crizotinib improved PFS versus chemotherapy in ALK positive patients (median PFS 19.67m vs 5.47m; p < 0.001). Moreover, crizotinib obtained an ICER of US$36,285.39 before the end of 2016, when crizotinib, pemetrexed and anti-angiogenesis drugs were not MI covered. This is more than the willingness to pay threshold (three-times of gross domestic product per capita in mainland China or Sichuan Province). However, ICER was US$7321.16, which is less than willingness to pay, when crizotinib and all chemotherapy drugs were covered by MI from the end of 2016. Sensitivity analysis demonstrated a 99.7% probability for crizotinib to be more cost-effective than chemotherapy, when crizotinib and all anticancer drugs were MI covered. One-way sensitivity analysis for the reimbursement ratio of crizotinib indicated that cost-effective tendency for crizotinib increased as reimbursement ratio increased. Conclusion: Crizotinib could be an effective, and cost-effective first-line treatment for ALK positive advanced NSCLC with the MI coverage currently available in Chengdu, Sichuan Province, China.

P2.13-04 Outcomes of ALK-Positive Non-Small-Cell Lung Cancer (NSCLC) Patients Treated with Crizotinib: A Multicenter Cohort Retrospective Study.

Crizotinib has demonstrated promising efficacy in patients with anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) in clinical trials. However, there is lack of multicenter real-world data summary with large cohort of patients, especially in China. We conducted this multicenter and retrospective study to assess the outcomes of crizotinib in, to our knowledge, the largest cohort of patients with ALK-positive advanced NSCLC. We reviewed medical records of 484 unselected ALK-positive NSCLC patients treated with crizotinib at five cancer centers in China from January 2013 to November 2017. Clinical data were collected from crizotinib initiation to RECIST-defined progressive disease (PD), and post-PD systemic treatment outcomes were also analyzed. A total of 428 eligible ALK-positive NSCLC patients were enrolled. Among them, 273 (63.8%) patients received crizotinib as first-line treatment. The median progression-free survival (PFS) and overall survival (OS) from crizotinib initiation were 14.4 months (95%CI: 12.4-16.4) and 53.4 months (95% CI: 33.7-73.1) respectively. In the subgroup analysis, patients received crizotinib as first-line treatment showed a higher disease control rate (DCR) and longer median OS with statistical significance compared with second-/ further line crizotinib treatment (94.8%, not estimated vs. 89.0%, 40.5 months, respectively). For 261 patients with RECIST-defined PD, multivariate COX analysis revealed that patients who received first-line crizotinib (P=0.013), continued crizotinib beyond progressive disease (CBPD) (P=0.011) and received next-generation ALKis after crizotinib failure (P<0.001) were associated with improved survival both from crizotinib progression and from the first crizotinib dose. This study demonstrated the clinically meaningful benefit of crizotinib treatment in the largest cohort of Chinese ALK positive NSCLC patients. CBPD and next-generation ALK TKI treatment may provide survival improvement after RECIST-defined progression on crizotinib.

Outcomes of ALK positive lung cancer patients treated with crizotinib or second-generation ALK inhibitor: a monoinstitutional experience

Rearrangement in the anaplastic lymphoma kinase (ALK) gene is one of the oncogenic drivers in non-small cell lung cancer (NSCLC) patients.Several ALK inhibitors (ALKis) have been developed and have demonstrated their efficacy, however the best treatment strategy for ALK positive NSCLC patients has yet to be determined. Our retrospective study has investigated the outcome of 40 ALK-rearranged NSCLC patients treated with two different sequential strategies in our Institute; a “classical group”, treated with crizotinib followed by second or third generation ALKis, and the “experimental group”, treated upfront with a second generation ALK inhibitor. The primary endpoints investigated were Progression-free survival (PFS) and intracranial activity. The analysis has revealed a significant improvement in PFS (p = 0.050) in the experimental group, furthermore none of these patients developed brain metastasis. There was no statistically significant difference in OS, but all patients in the experimental group were still alive after a median follow up of 15 months. Our retrospective analysis suggests that systemic and intracranial efficacy tends to be better in the experimental group; randomized prospective studies could confirm our observations.

Molecular Dynamics Validation of Crizotinib Resistance to ALK Mutations (L1196M and G1269A) and Identification of Specific Inhibitors.

Anaplastic lymphoma kinase (ALK) positive non-small cell lung cancer (NSCLC) patients are mostly treated with ALK tyrosine kinase inhibitors (TKIs). Crizotinib is the first generation ALK inhibitor practiced as a primary chemo to combat cancer cells followed by second generation inhibitor ceritinib which are effective against crizotinib resistant ALK mutations. However, patients treated with these drugs invariably relapsed because of the development of new drug resistance mutations. In this study we explored the crizotinib resistance in the presence of ALK mutations L1196M and G1269A through molecular dynamics simulation studies. Further mutation specific inhibitors CID 71748211 and CID 71728095 were identified to potentially inhibit ALK with mutations L1196M and G1269A, respectively. This computational investigation in-sighted the molecular factors involved in crizotinib resistance which enhanced in the identification of new ALK drugs that brings individualized medicine to treat ALK positive NSCLC patients with specific mutations. J. Cell. Biochem. 118: 3462-3471, 2017. © 2017 Wiley Periodicals, Inc.

Anaplastic lymphoma kinase-positive lung adenocarcinoma patient with development of sick sinus syndrome while on targeted treatment with crizotinib.

The anaplastic lymphoma kinase (ALK) positive non-small cell lung cancer (NSCLC) patients are younger and have never smoked, while pathologically are predominately adenocarcinomas. Crizotinib as an ALK inhibitor has been used in treating ALK positive NSCLC patients for several years and some adverse effects should be paid attention to. We now describe a case of ALK positive NSCLC patient with development of sick sinus syndrome (SSS) while on targeted treatment with crizotinib. A 46-year-old non-smoking woman with right hilar mass and underwent transesophageal endoscopic ultrasonography lymph node biopsy showed low differentiation adenocarcinoma, immunohistochemistry (IHC) of tumor samples revealed the ALK overexpression. The severe sinus bradycardia and RR interval prolongation were detected 3 months after crizotinib treatment, she underwent pacemaker implantation. Although the severe sinus bradycardia and RR interval prolongation were unusual adverse effects, physicians should be aware of these side effects when using crizotinib.

Treatment of patients with ALK gene rearranged non-small cell lung cancer after resistance to crizotinib

肺癌是全球发病率和致死率最高的疾病之一。非小细胞肺癌（non-small cell lung cancer, NSCLC）是肺癌最为常见的组织学类型。近些年，分子生物学的发展让我们对NSCLC的认识从组织水平深入到分子水平。表皮生长因子受体（epidermal growth factor receptor, EGFR）基因突变和间变性淋巴瘤激酶（anaplastic lymphoma kinase, ALK）融合基因是NSCLC患者最为重要的两个肿瘤驱动基因。针对它们的酪氨酸激酶抑制剂（tyrosine kinase inhibitors, TKIs）显著改善了带有这类分子特征的NSCLC患者的生存。不幸的是，目前几乎所有针对这两种突变的初始靶向治疗都会不可避免地出现耐药问题。有关EGFR-TKIs的耐药机制及其应对策略已经有很多文章进行阐述，而对于ALK TKIs治疗后出现耐药问题的机制和相应的治疗策略还未曾有过详细的综述。因此，本文针对一代ALK TKI（克唑替尼）治疗ALK融合基因阳性的NSCLC患者（ALK+ NSCLC）后引起耐药问题的机制和有关后续治疗策略做一综述。

Acquired Resistance to a New Alk Inhibitor, Alectinib in Lung Cancer

ABSTRACT Aim: Alectinib (CH/RO5424802) is a second generation anaplastic lymphoma kinase (ALK)-tyrosine kinase inhibitor (TKI). It has been reported to overcome acquired resistance to the first generation ALK-TKI, crizotinib, in a preclinical study (Cancer Cell 19, 2011: 679-90). A phase I/II clinical trial of alectinib for ALK positive non-small cell lung cancer (NSCLC) showed an unprecedented response rate (93.5 % in phase II portion) and the drug seemed to lead to less toxicities than crizotinib (Lancet Oncol 14, 2013: 590-98). However, subsequent resistance to alectinib is expected after its approval. Thus, we need to consider the therapeutic strategy to overcome the resistance to alectinib in advance. Methods: Two alectinib-resistant H2228/CHR and ABC-11/CHR NSCLC cell lines from H2228 and ABC-11, respectively, harboring EML4-ALK fusion genes were established by continuous exposure to alectinib. We characterized the resistant cell lines using MTT assay, western blotting, immunohistochemistry, polymerase chain reaction, fluorescent in situ hybridization, phospho-receptor tyrosine kinase array, comparative genomic hybridization, RNA array, ELISA and xenograft models. Results: H2228/CHR and ABC-11/CHR cells showed 130-fold and 17-fold higher resistance to alectinib than their respective parent cells in vitro. H2228/CHR cells had lost EML4-ALK fusion gene and ALK protein expression. In addition, the resistant cells overexpressed IGF1R, and were sensitive to IGF1R-TKI (TAE684) as a result. While ABC-11/CHR cells reduced phospho-ALK in spite of preservation of total ALK protein, they activated MET with increment of its ligand (hepatocyte growth factor) as an autocrine action. Because crizotinib originally functions as MET-TKI along with ALK-TKI, ABC-11/CHR was sensitive to the drug both in vitro and in vivo. Conclusions: Loss or inactivation of ALK leads to the acquired resistance to alectinib in the two cell lines we established. In addition, signaling switch from ALK to IGF1R or MET was observed. IGF1R inhibitor or MET inhibitor was effective on such cases. Thus, ALK positive NSCLC patients refractory to alectinib might benefit from IGF1R or MET inhibitors. Disclosure: K. Hotta: Honoraria from speaker's bureau from Chugai pharmaceutical CO., LTD.; N. Takigawa: Honoraria from speaker's bureau from Pfizer Inc. Japan; K. Kiura: Honoraria from speaker's bureau from Chugai pharmaceutical CO., LTD., Pfizer Inc. Japan and Novartis Pharma K.K. All other authors have declared no conflicts of interest.

Stereotactic Radiation Therapy can Safely and Durably Control Sites of Extra-Central Nervous System Oligoprogressive Disease in Anaplastic Lymphoma Kinase-Positive Lung Cancer Patients Receiving Crizotinib

To analyze the durability and toxicity of radiotherapeutic local ablative therapy (LAT) applied to extra-central nervous system (eCNS) disease progression in anaplastic lymphoma kinase-positive non-small cell lung cancer (NSCLC) patients. Anaplastic lymphoma kinase-positive NSCLC patients receiving crizotinib and manifesting ≤ 4 discrete sites of eCNS progression were classified as having oligoprogressive disease (OPD). If subsequent progression met OPD criteria, additional courses of LAT were considered. Crizotinib was continued until eCNS progression was beyond OPD criteria or otherwise not suitable for further LAT. Of 38 patients, 33 progressed while taking crizotinib. Of these, 14 had eCNS progression meeting OPD criteria suitable for radiotherapeutic LAT. Patients with eCNS OPD received 1-3 courses of LAT with radiation therapy. The 6- and 12-month actuarial local lesion control rates with radiation therapy were 100% and 86%, respectively. The 12-month local lesion control rate with single-fraction equivalent dose >25 Gy versus ≤ 25 Gy was 100% versus 60% (P=.01). No acute or late grade >2 radiation therapy-related toxicities were observed. Median overall time taking crizotinib among those treated with LAT versus those who progressed but were not suitable for LAT was 28 versus 10.1 months, respectively. Patients continuing to take crizotinib for >12 months versus ≤ 12 months had a 2-year overall survival rate of 72% versus 12%, respectively (P<.0001). Local ablative therapy safely and durably eradicated sites of individual lesion progression in anaplastic lymphoma kinase-positive NSCLC patients receiving crizotinib. A dose-response relationship for local lesion control was observed. The suppression of OPD by LAT in patients taking crizotinib allowed an extended duration of exposure to crizotinib, which was associated with longer overall survival.

Abstract 4465: Concurrent roles for IGF1R and EGFR in driving acquired resistance to crizotinib and ability to overcome with a combination of the ALK/IGF1R inhibitor AZD3463 and Iressa.

Abstract Genomic rearrangement of Anaplastic Lymphoma Kinase (ALK) has been observed in several tumor types including 3-6% of non small cell lung cancer (NSCLC). Although the ALK inhibitor crizotinib has clinical efficacy in selected ALK positive NSCLC patients, the majority of patients who show initial responses eventually relapse. Various mechanisms leading to resistance have been proposed and include ALK amplification and resistance mutations, as well as alternative pathway drivers including EGFR and cKIT. To further evaluate potential mechanisms of acquired resistance to crizotinib and potential therapeutic strategies to overcome them, we have developed multiple independently generated cell line derivatives. H3122 cells, a NSCLC line with an EML4-ALK fusion, was selected in increasing concentrations of crizotinib up to 1uM over a period of 4 to 6 months to generate H3122-CR lines. The cell lines generated were confirmed to be resistance to crizotinib as well as the selective ALK inhibitor, CH5424802, in cell proliferation experiments. Evaluation of the levels of potential secondary receptor tyrosine kinase (RTK) drivers by phosphoRTK arrays and western blotting revealed increased levels of total and phosphorylated ALK (pALK), along with increased phosphorylated insulin-like growth factor 1 receptor (pIGF1R). ALK levels were also elevated at the mRNA level. To evaluate potential strategies to most effectively overcome resistance in these cell lines, selective inhibitors of ALK CH5424802, IGF1R OSI-906 and epidermal growth factor receptor (EGFR) Iressa were used alone and in combination to evaluate ability to inhibit growth of two of the H3122-CR lines. In both CR lines, OSI-906 and Iressa had no effect alone on cell growth, however a combination of CH5424802 and OSI-906 or CH5424802 and Iressa increased sensitivity to CH5424802. Most interestingly however, a combination of CH5424802, OSI-906 and Iressa had maximal sensitization effect with complete reversal of resistance observed. A similar finding was obtained with a combination of the ALK/IGF1R inhibitor AZD3463 with Iressa. Further, we were able to demonstrate pathway dependency shifts in the CR lines with OSI-906 inhibiting AKT and Iressa inhibiting ERK and a combination of CH5424802, OSI-906 and Iressa required to effectively repress these main pathways to the level observed with CH5424802 alone in the H3122 parental line. Together, these data support a potential role for both EGFR and IGF1R as secondary RTK drivers occurring concurrently to drive resistance to crizotinib. A combination of approaches inhibiting ALK, IGF1R and EGFR together may therefore be required to most effectively treat crizotinib relapsed patients and delay onset of resistance. This could be achieved by combining multiple selective agents or agents with polypharmacology such as AZD3463 along with Iressa. Citation Format: Lisa Drew, Jeffrey Engelman, Ryohei Katayama, Brenda McDermott, Jamal Saeh, Meghan Scarpitti, Alice Shaw, Minhui Shen, Suping Wang, Graeme Smith. Concurrent roles for IGF1R and EGFR in driving acquired resistance to crizotinib and ability to overcome with a combination of the ALK/IGF1R inhibitor AZD3463 and Iressa. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4465. doi:10.1158/1538-7445.AM2013-4465

Abstract 919: AZD3463, a novel ALK/IGF1R inhibitor, overcomes multiple mechanisms of acquired resistance to crizotinib.

Abstract Genomic rearrangement of Anaplastic Lymphoma Kinase (ALK) has been observed in several tumor types including 60-80% anaplastic large cell lymphoma (ALCL) and 3-6% of non small cell lung cancer (NSCLC). Although the ALK inhibitor crizotinib has clinical efficacy in selected ALK positive NSCLC patients, the majority of patients who show initial responses eventually relapse. Various mechanisms leading to resistance have been proposed and include ALK amplification and resistance mutations, as well as alternative pathway drivers including EGFR, cKIT and, more recently, IGF1R. We have discovered a novel and potent inhibitor of ALK, AZD3463 with a Ki value of 0.75nM which also inhibits additional receptor tyrosine kinases including insulin growth factor receptor (IGF1R) with equivalent potency. AZD3463 inhibits ALK in cells as demonstrated by its ability to decrease ALK autophosphorylation in tumor cell lines containing ALK fusions including DEL (ALCL NPM-ALK), H3122 (NSCLC EML4-ALK) and H2228 (NSCLC EML4-ALK). Inhibition of ALK is associated with perturbations in downstream signaling including ERK, AKT and STAT3 pathways leading to preferential inhibition of proliferation in the ALK fusion containing cell lines in vitro. AZD3463 also demonstrates the ability to dose dependently inhibit pALK in xenograft tumors in vivo resulting in stasis (H3122) or regression (DEL, H2228). AZD3463 retains good activity against a number of clinically relevant crizotinib resistant mutations including the gatekeeper mutant L1196M where equivalent potency to wild type ALK is observed in vitro and in vivo in EML4-ALK containing BAF3 cell lines. To further assess the potential ability of AZD3463 to overcome additional resistance mechanisms, antiproliferative activity was assessed in multiple crizotinib resistant cell lines independently derived in vitro from H3122 cells as well as a patient derived crizotinib relapsed model. These resistant cell lines contain multiple resistance mechanisms including the L1196M gatekeeper and T115Ins mutations, ALK amplification and/or secondary drivers including EGFR and IGF1R. AZD3463 retains antiproliferative potency within 4 fold of parental H3122 cells for 10 out of 12 of these acquired resistance models in vitro. In summary, AZD3463 is a potent ALK inhibitor which inhibits additional kinases including IGF1R and has activity in a number of crizotinib resistant models driven by multiple resistance mechanisms. Citation Format: Lisa Drew, Jane Cheng, Jeffrey Engelman, Douglas Ferguson, Ryohei Katayama, Brenda McDermott, Jamal Saeh, Alice Shaw, Minhui Shen, Dan Widzowski, Allan Wu, Graeme Smith. AZD3463, a novel ALK/IGF1R inhibitor, overcomes multiple mechanisms of acquired resistance to crizotinib. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 919. doi:10.1158/1538-7445.AM2013-919