Jennifer L. Carter

The FGFR Landscape in Cancer: Analysis of 4,853 Tumors by Next-Generation Sequencing

Purpose: Molecular profiling may have prognostic and predictive value, and is increasingly used in the clinical setting. There are more than a dozen fibroblast growth factor receptor (FGFR) inhibitors in development. Optimal therapeutic application of FGFR inhibitors requires knowledge of the rates and types of FGFR aberrations in a variety of cancer types. Experimental Design: We analyzed frequencies of FGFR aberrations in 4,853 solid tumors that were, on physician request, tested in a Clinical Laboratory Improvement Amendments (CLIA) laboratory (Foundation Medicine) using next-generation sequencing (182 or 236 genes), and analyzed by N-of-One. Results: FGFR aberrations were found in 7.1% of cancers, with the majority being gene amplification (66% of the aberrations), followed by mutations (26%) and rearrangements (8%). FGFR1 (mostly amplification) was affected in 3.5% of 4,853 patients; FGFR2 in 1.5%; FGFR3 in 2.0%; and FGFR4 in 0.5%. Almost every type of malignancy examined showed some patients with FGFR aberrations, but the cancers most commonly affected were urothelial (32% FGFR-aberrant); breast (18%); endometrial (∼13%), squamous lung cancers (∼13%), and ovarian cancer (∼9%). Among 35 unique FGFR mutations seen in this dataset, all but two are found in COSMIC. Seventeen of the 35 are known to be activating, and 11 are transforming. Conclusions: FGFR aberrations are common in a wide variety of cancers, with the majority being gene amplifications or activating mutations. These data suggest that FGFR inhibition could be an important therapeutic option across multiple tumor types. Clin Cancer Res; 22(1); 259–67. ©2015 AACR.

Response to Crizotinib in a Patient With Lung Adenocarcinoma Harboring a MET Splice Site Mutation

MET (c-MET; mesenchymal-epithelial transition factor) is a receptor tyrosine kinase that was first characterized as a proto-oncogene in 1984, in a chemically transformed osteosarcoma cell line [1]. Located on chromosome 7q21-31, the MET gene encodes a cell surface receptor tyrosine kinase comprised of a 50-kDa α-chain and a 140-kDa transmembrane β-chain linked by a disulfide bond. The natural ligand for cMet is hepatocyte growth factor (HGF), also known as scatter factor [2]. Following binding of HGF the c-MET receptor undergoes dimerization and phosphorylation, which in turn promotes recruitment of downstream effector proteins, leading to activation of multiple signaling cascades, including the MAPK, PI3K/Akt, STAT and NF-κB pathways [3]. Physiologic roles for HGF/MET signaling include embryogenesis, development, and wound healing [3–5]. Aberrant activation of the c-Met receptor tyrosine kinase promotes oncogenicity in a subset of lung adenocarcinomas. A variety of mechanisms can result in constitutive c-Met signaling, including MET gene amplification, protein overexpression, activating point mutations, and induction of its ligand HGF [3, 6, 7]. Crizotinib, a multitargeted tyrosine kinase inhibitor (TKI) that is FDA approved for the therapy of lung adenocarcinomas harboring ALK or ROS1 fusions [8–10], was also recently found to be clinically active in tumors with high level MET amplification [11]. These findings have prompted the clinical development of more selective c-MET inhibitors for evaluation in this particular patient population. MET splice site mutation has also been demonstrated to induce constitutive activity and confer sensitivity to c-Met inhibition in vitro [12, 13]. Indeed, frequent activating MET splice site mutations were recently described in whole exome sequencing (WES) discovery efforts in lung adenocarcinoma [14]. However, the clinical activity of c-Met inhibition in this context remains unknown. We identified one such mutation using targeted next generation sequencing (NGS) in a patient with lung adenocarcinoma and treated him with crizotinib.

Squamousness: Next-generation sequencing reveals shared molecular features across squamous tumor types

In order to gain a better understanding of the underlying biology of squamous cell carcinoma (SCC), we tested the hypothesis that SCC originating from different organs may possess common molecular alterations. SCC samples (N = 361) were examined using clinical-grade targeted next-generation sequencing (NGS). The most frequent SCC tumor types were head and neck, lung, cutaneous, gastrointestinal and gynecologic cancers. The most common gene alterations were TP53 (64.5% of patients), PIK3CA (28.5%), CDKN2A (24.4%), SOX2 (17.7%), and CCND1 (15.8%). By comparing NGS results of our SCC cohort to a non-SCC cohort (N = 277), we found that CDKN2A, SOX2, NOTCH1, TP53, PIK3CA, CCND1, and FBXW7 were significantly more frequently altered, unlike KRAS, which was less frequently altered in SCC specimens (all P < 0.05; multivariable analysis). Therefore, we identified “squamousness” gene signatures (TP53, PIK3CA, CCND1, CDKN2A, SOX2, NOTCH 1, and FBXW7 aberrations, and absence of KRAS alterations) that were significantly more frequent in SCC versus non-SCC histologies. A multivariable co-alteration analysis established 2 SCC subgroups: (i) patients in whom TP53 and cyclin pathway (CDKN2A and CCND1) alterations strongly correlated but in whom PIK3CA aberrations were less frequent; and (ii) patients with PIK3CA alterations in whom TP53 mutations were less frequent (all P ≤ 0 .001, multivariable analysis). In conclusion, we identified a set of 8 genes altered with significantly different frequencies when SCC and non-SCC were compared, suggesting the existence of patterns for “squamousness.” Targeting the PI3K-AKT-mTOR and/or cyclin pathway components in SCC may be warranted.

RET aberrations in diverse cancers: Next-generation sequencing of 4,871 patients

Purpose: Aberrations in genetic sequences encoding the tyrosine kinase receptor RET lead to oncogenic signaling that is targetable with anti-RET multikinase inhibitors. Understanding the comprehensive genomic landscape of RET aberrations across multiple cancers may facilitate clinical trial development targeting RET. Experimental Design: We interrogated the molecular portfolio of 4,871 patients with diverse malignancies for the presence of RET aberrations using Clinical Laboratory Improvement Amendments–certified targeted next-generation sequencing of 182 or 236 gene panels. Results: Among diverse cancers, RET aberrations were identified in 88 cases [1.8% (88/4, 871)], with mutations being the most common alteration [38.6% (34/88)], followed by fusions [30.7% (27/88), including a novel SQSTM1-RET] and amplifications [25% (22/88)]. Most patients had coexisting aberrations in addition to RET anomalies [81.8% (72/88)], with the most common being in TP53-associated genes [59.1% (52/88)], cell cycle–associated genes [39.8% (35/88)], the PI3K signaling pathway [30.7% (27/88)], MAPK effectors [22.7% (20/88)], or other tyrosine kinase families [21.6% (19/88)]. RET fusions were mutually exclusive with MAPK signaling pathway alterations. All 72 patients harboring coaberrations had distinct genomic portfolios, and most [98.6% (71/72)] had potentially targetable coaberrations with either an FDA-approved or an investigational agent. Two cases with lung (KIF5B-RET) and medullary thyroid carcinoma (RET M918T) that responded to a vandetanib (multikinase RET inhibitor)-containing regimen are shown. Conclusions: RET aberrations were seen in 1.8% of diverse cancers, with most cases harboring actionable, albeit distinct, coexisting alterations. The current report suggests that optimal targeting of patients with RET anomalies will require customized combination strategies. Clin Cancer Res; 23(8); 1988–97. ©2016 AACR.

Genomic landscape of salivary gland tumors.

Effective treatment options for advanced salivary gland tumors are lacking. To better understand these tumors, we report their genomic landscape. We studied the molecular aberrations in 117 patients with salivary gland tumors that were, on physician request, tested in a Clinical Laboratory Improvement Amendments (CLIA) laboratory (Foundation Medicine, Cambridge, MA) using next-generation sequencing (182 or 236 genes), and analyzed by N-of-One, Inc. (Lexington, MA). There were 354 total aberrations, with 240 distinct aberrations identified in this patient population. Only 10 individuals (8.5%) had a molecular portfolio that was identical to any other patient (with four different portfolios amongst the ten patients). The most common abnormalities involved the TP53 gene (36/117 [30.8% of patients]), cyclin pathway (CCND1, CDK4/6 or CDKN2A/B) (31/117 [26.5%]) and PI3K pathway (PIK3CA, PIK3R1, PTEN or AKT1/3) (28/117 [23.9%]). In multivariate analysis, statistically significant co-existing aberrations were observed as follows: TP53 and ERBB2 (p = 0.01), cyclin pathway and MDM2 (p = 0.03), and PI3K pathway and HRAS (p = 0.0001). We were able to identify possible cognate targeted therapies in most of the patients (107/117 [91.5%]), including FDA-approved drugs in 80/117 [68.4%]. In conclusion, salivary gland tumors were characterized by multiple distinct aberrations that mostly differed from patient to patient. Significant associations between aberrations in TP53 and ERBB2, the cyclin pathway and MDM2, and HRAS and the PI3K pathway were identified. Most patients had actionable alterations. These results provide a framework for tailored combinations of matched therapies.

Genomic portfolio of Merkel cell carcinoma as determined by comprehensive genomic profiling: implications for targeted therapeutics.

Merkel cell carcinoma is an ultra-rare cutaneous neuroendocrine cancer for which approved treatment options are lacking. To better understand potential actionability, the genomic landscape of Merkel cell cancers was assessed. The molecular aberrations in 17 patients with Merkel cell carcinoma were, on physician request, tested in a Clinical Laboratory Improvement Amendments (CLIA) laboratory (Foundation Medicine, Cambridge, MA) using next-generation sequencing (182 or 236 genes) and analyzed by N-of-One, Inc. (Lexington, MA). There were 30 genes harboring aberrations and 60 distinct molecular alterations identified in this patient population. The most common abnormalities involved the TP53 gene (12/17 [71% of patients]) and the cell cycle pathway (CDKN2A/B, CDKN2C or RB1) (12/17 [71%]). Abnormalities also were observed in the PI3K/AKT/mTOR pathway (AKT2, FBXW7, NF1, PIK3CA, PIK3R1, PTEN or RICTOR) (9/17 [53%]) and DNA repair genes (ATM, BAP1, BRCA1/2, CHEK2, FANCA or MLH1) (5/17 [29%]). Possible cognate targeted therapies, including FDA-approved drugs, could be identified in most of the patients (16/17 [94%]). In summary, Merkel cell carcinomas were characterized by multiple distinct aberrations that were unique in the majority of analyzed cases. Most patients had theoretically actionable alterations. These results provide a framework for investigating tailored combinations of matched therapies in Merkel cell carcinoma patients.

Genomic Landscape of Malignant Mesotheliomas.

Understanding the genomic landscape of malignant mesothelioma may identify novel molecular drivers of this ultra-rare disease, which can lead to an expanded roster of targeted therapies and clinical trial options for patients with mesothelioma. We examined the molecular profiles of 42 patients with malignant mesothelioma (including pleural, peritoneal, and pericardial) that were referred by clinicians to be tested in a Clinical Laboratory Improvement Amendments (CLIA) laboratory using next-generation sequencing (NGS; 182 or 236 genes). Among 42 patients, there were 116 alterations, with 92 being distinct. The number of genomic alterations per patient ranged from 1 to 5 (median = 3). No two patients had identical molecular portfolios. The most common aberrations were in BAP1 (BRCA1-associated protein 1; 47.6% [20/42]), NF2 (38.1% [16/42]), and CDKN2A/B (loss) (35.7% [15/42]). BAP1 alterations and CDKN2A/B loss were associated with pleural mesothelioma (OR 3.4, P = 0.059 [BAP1] [trend]; OR 5.8, P = 0.01 [CDKN2A/B]). All 42 patients had a molecular abnormality that was potentially actionable (median = three actionable alterations per patient; range, 1 to 5), and, in 40 patients (95.2%), a drug approved by the FDA was applicable. In conclusion, each individual with malignant mesothelioma harbored a unique set of genomic aberrations, suggesting that NGS-based profiling of patients will be needed if patients are to be optimally matched to cognate treatments. All 42 patients had at least one alteration that was, in theory, pharmacologically tractable. Mol Cancer Ther; 15(10); 2498–507. ©2016 AACR.

Cell-Cycle Gene Alterations in 4,864 Tumors Analyzed by Next-Generation Sequencing: Implications for Targeted Therapeutics

Alterations in the cyclin-dependent kinase (CDK)-retinoblastoma (RB) machinery disrupt cell-cycle regulation and are being targeted in drug development. To understand the cancer types impacted by this pathway, we analyzed frequency of abnormalities in key cell-cycle genes across 4,864 tumors using next-generation sequencing (182 or 236 genes; Clinical Laboratory Improvement Amendments laboratory). Aberrations in the cell-cycle pathway were identified in 39% of cancers, making this pathway one of the most commonly altered in cancer. The frequency of aberrations was as follows: CDKN2A/B (20.1% of all patients), RB1 (7.6%), CCND1 (6.1%), CCNE1 (3.6%), CDK4 (3.2%), CCND3 (1.8%), CCND2 (1.7%), and CDK6 (1.7%). Rates and types of aberrant cell-cycle pathway genes differed between cancer types and within histologies. Analysis of coexisting and mutually exclusive genetic aberrations showed that CCND1, CCND2, and CCND3 aberrations were all positively associated with CDK6 aberrations [OR and P values, multivariate analysis: CCND1 and CDK6 (OR = 3.5; P < 0.0001), CCND2 and CDK6 (OR = 4.3; P = 0.003), CCND3 and CDK6 (OR = 3.6; P = 0.007)]. In contrast, RB1 alterations were negatively associated with multiple gene anomalies in the cell-cycle pathway, including CCND1 (OR = 0.25; P = 0.003), CKD4 (OR = 0.10; P = 0.001), and CDKN2A/B (OR = 0.21; P < 0.0001). In conclusion, aberrations in the cell-cycle pathway were very common in diverse cancers (39% of 4,864 neoplasms). The frequencies and types of alterations differed between and within tumor types and will be informative for drug development strategies. Mol Cancer Ther; 15(7); 1682–90. ©2016 AACR.

Company Profile: N-of-One: realizing personalized medicine

N-of-One is at the forefront of personalized medicine. The companys mission is to act as a bridge between the research community, diagnostic laboratories, the treating oncologist and the patient to develop customized cancer diagnostic and treatment strategies. N-of-One provides physicians and patients with relevant insight regarding molecular profiling technologies and facilitates rapid, high-quality testing of patient tissues. In addition to expanding treatment options, the services provided by N-of-One potentially provide cost savings by guiding patients and physicians toward more evidence-based, data-driven treatment approaches.

Next-generation sequencing of prostate cancer: genomic and pathway alterations, potential actionability patterns, and relative rate of use of clinical-grade testing

ABSTRACT Despite being one of the most common cancers, treatment options for prostate cancer are limited. Novel approaches for advanced disease are needed. We evaluated the relative rate of use of clinical-grade next generation sequencing (NGS) in prostate cancer, as well as genomic alterations identified and their potential actionability. Of 4864 patients from multiple institutions for whom NGS was ordered by physicians, only 67 (1.4%) had prostate cancer, representing 1/10 the ordering rate for lung cancer. Prostate cancers harbored 148 unique alterations affecting 63 distinct genes. No two patients had an identical molecular portfolio. The median number of characterized genomic alterations per patient was 3 (range, 1 to 9). Fifty-six of 67 patients (84%) had ≥ 1 potentially actionable alteration. TMPRSS2 fusions affected 28.4% of patients. Genomic aberrations were most frequently detected in TP53 (55.2% of patients), PTEN (29.9%), MYC (17.9%), PIK3CA (13.4%), APC (9.0%), BRCA2 (9.0%), CCND1 (9.0%), and RB1 genes (9.0%). The PI3K (52.2% of patients), WNT (13.5%), DNA repair (17.9%), cell cycle (19.4%), and MAPK (14.9%) machinery were commonly impacted. A minority of patients harbored BRAF, NTRK, ERBB2, or mismatch repair gene abnormalities, which are highly druggable in some cancers. Only ~ 10% of prostate cancer trials (clinicaltrials.gov, year 2017) applied a (non-hormone) biomarker before intervention. In conclusion, though use of clinical-grade NGS is relatively low and only a minority of trials deploy DNA-based biomarkers, many prostate cancer-associated molecular alterations may be pharmacologically tractable with genomcially targeted therapy or, in the case of mismatch repair anomalies, with checkpoint inhibitor immunotherapy.