Gregory Riedlinger

Patient-Derived Xenograft Models of Non-Small Cell Lung Cancer and Their Potential Utility in Personalized Medicine

Traditional preclinical studies of cancer therapeutics have relied on the use of established human cell lines that have been adapted to grow in the laboratory and, therefore, may deviate from the cancer they were meant to represent. With the emphasis of cancer drug development shifting from non-specific cytotoxic agents to rationally designed molecularly targeted therapies or immunotherapy comes the need for better models with predictive value regarding therapeutic activity and response in clinical trials. Recently, the diversity and accessibility of immunodeficient mouse strains has greatly enhanced the production and utility of patient-derived xenograft (PDX) models for many tumor types, including non-small cell lung cancer (NSCLC). Combined with next-generation sequencing, NSCLC PDX mouse models offer an exciting tool for drug development and for studying targeted therapies while utilizing patient samples with the hope of eventually aiding in clinical decision-making. Here, we describe NSCLC PDX mouse models generated by us and others, their ability to reflect the parental tumors’ histomorphological characteristics, as well as the effect of clonal selection and evolution on maintaining genomic integrity in low-passage PDXs compared to the donor tissue. We also raise vital questions regarding the practical utility of PDX and humanized PDX models in predicting patient response to therapy and make recommendations for addressing those questions. Once collaborations and standardized xenotransplantation and data management methods are established, NSCLC PDX mouse models have the potential to be universal and invaluable as a preclinical tool that guides clinical trials and standard therapeutic decisions.

Use of comprehensive genomic profiling to direct point-of-care management of patients with gynecologic cancers

OBJECTIVE To determine the feasibility and clinical utility of using comprehensive genomic profiling (CGP) in the course of clinical care to identify clinically relevant tumor genomic alterations for patients with either rare or refractory gynecologic cancers to facilitate point-of-care management. Use of an expert, multidisciplinary, institutional molecular tumor board (MTB) assessment is discussed regarding input on putative targeted options for individualized therapy. METHODS A prospective clinical trial is ongoing. We report on the initial 69 patients with gynecologic cancers that were either rare or refractory to standard therapy. CGP was performed by Foundation Medicine, Inc. Genomic alterations were reviewed by members of an MTB. Consensus recommendations on genomically targeted, FDA-approved, on- and off-label therapies and clinical trials were sent to the treating physician, and decisions and outcomes were assessed. RESULTS Study outcomes were available for 64 patients. The mean number of genes altered per tumor was 4.97 (median=4; range, 1-26), and the average turnaround time from testing laboratory report to generation of formal recommendations was approximately three weeks. Evaluation of genomic and clinical data by the MTB led to generation of targeted treatment options in all 64 patients, and the percentage of patients for whom one or more of these recommendations were implemented by the treating physician was 39%. Sixty-four percent of the patients receiving targeted therapy based on a CGP result experienced radiologic response or showed evidence of clinical benefit or stable disease. CONCLUSION These data suggest that an institutional MTB is a feasible venue for reviewing tumor genomic profiling results and generating clinical recommendations. These data also support the need for further studies and guidelines on clinical decision making with greater availability of broad genomically based diagnostics.

Cancer risk and clinicopathological characteristics of thyroid nodules harboring thyroid-stimulating hormone receptor gene mutations

Thyroid‐stimulating hormone receptor (TSHR) gene mutations play a critical role in thyroid cell proliferation and function. They are found in 20%‐82% of hyperfunctioning nodules, hyperfunctioning follicular thyroid cancers (FTC), and papillary thyroid cancers (PTC). The diagnostic importance of TSHR mutation testing in fine needle aspiration (FNA) specimens remains unstudied.

Endogenous retrovirus expression is associated with response to immune checkpoint blockade in clear cell renal cell carcinoma

Although a subset of clear cell renal cell carcinoma (ccRCC) patients respond to immune checkpoint blockade (ICB), predictors of response remain uncertain. We investigated whether abnormal expression of endogenous retroviruses (ERVs) in tumors is associated with local immune checkpoint activation (ICA) and response to ICB. Twenty potentially immunogenic ERVs (πERVs) were identified in ccRCC in The Cancer Genome Atlas data set, and tumors were stratified into 3 groups based on their expression levels. πERV-high ccRCC tumors showed increased immune infiltration, checkpoint pathway upregulation, and higher CD8+ T cell fraction in infiltrating leukocytes compared with πERV-low ccRCC tumors. Similar results were observed in ER+/HER2- breast, colon, and head and neck squamous cell cancers. ERV expression correlated with expression of genes associated with histone methylation and chromatin regulation, and πERV-high ccRCC was enriched in BAP1 mutant tumors. ERV3-2 expression correlated with ICA in 11 solid cancers, including the 4 named above. In a small retrospective cohort of 24 metastatic ccRCC patients treated with single-agent PD-1/PD-L1 blockade, ERV3-2 expression in tumors was significantly higher in responders compared with nonresponders. Thus, abnormal expression of πERVs is associated with ICA in several solid cancers, including ccRCC, and ERV3-2 expression is associated with response to ICB in ccRCC.

Comprehensive genomic profiling aids in treatment of a metastatic endometrial cancer

FGFR-TACC fusions, including FGFR3-TACC3, have been identified as potential oncogenic drivers and actionable alterations in a number of different cancer types. The clinical relevance of FGFR3-TACC3 fusions in endometrial cancer has not yet been described. Formalin-fixed, paraffin-embedded metastatic endometrial carcinoma from the spleen and peritoneum were sent for comprehensive genomic profiling (CGP) using the FoundationOne platform as part of a prospective tumor genomic profiling protocol. We report the identification of an FGFR3-TACC3 fusion in a case of metastatic endometrioid endometrial cancer. Other potentially actionable alterations detected in this specimen included PIK3CA T1025S and an uncharacterized rearrangement involving TSC2. The patient initially received an FGFR inhibitor as an investigational agent and experienced stable disease with complete resolution of a pelvic nodule; however, treatment had to be discontinued because of intolerable side effects. A PET/CT scan nearly 3 mo after discontinuation showed disease progression. She subsequently received the mTOR inhibitor, temsirolimus, later accompanied by letrozole, and achieved stable disease. Clinical benefit was attributed to the mTOR inhibitor as tumor stained negative for estrogen receptor. Temsirolimus was discontinued after >17 mo because of disease progression. FGFR inhibitors may have clinical benefit in the treatment of endometrial carcinoma with FGFR3-TACC3 fusions. Additionally, clinical benefit from an mTOR inhibitor may reflect a response to targeting the alteration in PIK3CA or TSC2. More research is needed to understand the activity of FGFR3-TACC3 fusions on tumors and to discover additional therapeutic options for endometrial carcinoma patients with this gene fusion.

Detection of clonal hematopoiesis of indeterminate potential in clinical sequencing of solid tumor specimens

TO THE EDITOR: Clonal hematopoiesis of indeterminate potential (CHIP) describes an expansion of hematopoietic stem cells that harbor somatic mutations[1][1][⇓][2][⇓][3][⇓][4]-[5][5] without an underlying hematologic malignancy or definitive morphologic evidence of dysplasia.[6][6] CHIP can

Roadmap to a Comprehensive Clinical Data Warehouse for Precision Medicine Applications in Oncology

Leading institutions throughout the country have established Precision Medicine programs to support personalized treatment of patients. A cornerstone for these programs is the establishment of enterprise-wide Clinical Data Warehouses. Working shoulder-to-shoulder, a team of physicians, systems biologists, engineers, and scientists at Rutgers Cancer Institute of New Jersey have designed, developed, and implemented the Warehouse with information originating from data sources, including Electronic Medical Records, Clinical Trial Management Systems, Tumor Registries, Biospecimen Repositories, Radiology and Pathology archives, and Next Generation Sequencing services. Innovative solutions were implemented to detect and extract unstructured clinical information that was embedded in paper/text documents, including synoptic pathology reports. Supporting important precision medicine use cases, the growing Warehouse enables physicians to systematically mine and review the molecular, genomic, image-based, and correlated clinical information of patient tumors individually or as part of large cohorts to identify changes and patterns that may influence treatment decisions and potential outcomes.

Abstract 3183: Delivery of point-of-care management to patients with gynecologic malignancies using comprehensive genomic profiling

INTRODUCTION: Gynecologic cancers were estimated to occur in 98,280 women in 2015 in the United States and result in 30,440 deaths (Siegel 2015). The most common forms of gynecologic cancers occur in the ovary and uterine corpus (Siegel, 2015). Various reasons for poor outcome in these cancers include the late stage of the disease at the time of diagnosis and therapy resistance. We sought to elucidate alternate treatment avenues based on the genomic profiles of recalcitrant or rare gynecologic tumors. In the process, we aim to determine both the clinical utility and the feasibility of using comprehensive genomic profiling (CGP) during clinical care to identify clinically relevant tumor genomic alterations for these patients while enabling point-of-care management. METHODS: As part of our ongoing prospective clinical trial, we report on the initial 69 patients with gynecologic cancers that were refractory to standard therapy. CGP was performed by Foundation Medicine, Inc. Genomic mutations and alterations were reviewed by members of an expert, multidisciplinary institutional molecular tumor board (MTB). Consensus recommendations by the MTB were provided to the treating physician on genomically targeted, clinically relevant, FDA-approved, on- and off-label therapies and clinical trials. The outcomes were assessed. RESULTS: Study outcomes were available for 64 patients. On average, patients had 4.97 genomic alterations per tumor (range 1-46), while the time from the testing laboratory report to the formulation of recommendations by the MTB was approximately 3-4 weeks. Targeted treatment options were recommended by the MTB for 93% of patients; 39% of these patients had the MTB-based recommendations implemented by the treating physician. A response or clinical benefit was seen in 56% of the patients receiving MTB-based targeted therapy. CONCLUSION: These data suggest that alternatives to standard therapies for recalcitrant gynecologic cancers can be found though CGP and subsequent analysis from members of an expert, multidisciplinary institutional MTB. The formulation of clinical recommendations by an MTB based on tumor genomic profiling results is a feasible option. Further research is needed to understand how this approach shapes clinical decision making. Citation Format: Lorna Rodriguez-Rodriguez, Kim M. Hirshfield, Veronica Rojas, Siraj Ali, Robert S. DiPaola, Darlene Gibbon, Sara Isani, Aliza Leiser, Gregory M. Riedlinger, Shridar Ganesan. Delivery of point-of-care management to patients with gynecologic malignancies using comprehensive genomic profiling. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3183.