Visualizing Engrafted Human Cancer and Therapy Responses in Immunodeficient Zebrafish.

Xenograft cell transplantation into immunodeficient mice has become the gold standard for assessing pre-clinical efficacy of cancer drugs, yet direct visualization of single-cell phenotypes is difficult. Here, we report an optically-clear prkdc-/-, il2rga-/- zebrafish that lacks adaptive and natural killer immune cells, can engraft a wide array of human cancers at 37°C, and permits the dynamic visualization of single engrafted cells. For example, photoconversion cell-lineage tracing identified migratory and proliferative cell states in human rhabdomyosarcoma, a pediatric cancer of muscle. Additional experiments identified the preclinical efficacy of combination olaparib PARP inhibitor and temozolomide DNA-damaging agent as an effective therapy for rhabdomyosarcoma and visualized therapeutic responses using a four-color FUCCI cell-cycle fluorescent reporter. These experiments identified that combination treatment arrested rhabdomyosarcoma cells in the G2 cell cycle prior to induction of apoptosis. Finally, patient-derived xenografts could be engrafted into our model, opening new avenues for developing personalized therapeutic approaches in the future.

Evaluation of endocrine resistance using ESR1 genotyping of circulating tumor cells and plasma DNA.

PURPOSE: Therapeutic efficacy of hormonal therapies to target estrogen receptor (ER)-positive breast cancer is limited by the acquisition of ligand-independent ESR1 mutations, which confer treatment resistance to aromatase inhibitors (AIs). Monitoring for the emergence of such mutations may enable individualized therapy. We thus assessed CTC- and ctDNA-based detection of ESR1 mutations with the aim of evaluating non-invasive approaches for the determination of endocrine resistance. PATIENTS AND METHODS: In a prospective cohort of 55 women with hormone receptor-positive metastatic breast cancer, we isolated circulating tumor cells (CTCs) and developed a high-sensitivity method for the detection of ESR1 mutations in these CTCs. In patients with sufficient plasma for the simultaneous extraction of circulating tumor DNA (ctDNA), we performed a parallel analysis of ESR1 mutations using multiplex droplet digital PCR (ddPCR) and examined the agreement between these two platforms. Finally, we isolated single CTCs from a subset of these patients and reviewed RNA expression to explore alternate methods of evaluating endocrine responsiveness. RESULTS: High-sensitivity ESR1 sequencing from CTCs revealed mono- and oligoclonal mutations in 22% of patients. These were concordant with plasma DNA sequencing in 95% of cases. Emergence of ESR1 mutations was correlated both with time to metastatic relapse and duration of AI therapy following such recurrence. The Presence of an ESR1 mutation, compared to ESR1 wild type, was associated with markedly shorter Progression-Free Survival on AI-based therapies (p = 0.0006), but unaltered to other non-AI-based therapies (p = 0.73). Compared with ESR1 mutant cases, AI-resistant CTCs with wild-type ESR1 showed an elevated ER-coactivator RNA signature, consistent with their predicted response to second-line hormonal therapies. CONCLUSION: Blood-based serial monitoring may guide the selection of precision therapeutics for women with AI-resistant ER-positive breast cancer.

Pulmonary adenocarcinoma with epidermal growth factor receptor-mutations in asbestos exposed non-smokers: A case series.

BACKGROUND: Cigarette smoke and asbestos are recognized causes of lung carcinoma and together promote carcinogenesis. Adenocarcinoma is currently the most common cause of lung cancer in the USA and it has been linked to both smoking and asbestos exposure. Mutations in the epidermal growth factor gene receptor (EGFR) occur predominantly in non-smokers with adenocarcinoma. Methods Mutations in the EGFR gene were investigated using next-generation sequencing. RESULTS: We report the presence of EGFR exon point mutations in the pulmonary adenocarcinomas of three never-smokers occupationally exposed to asbestos. CONCLUSION: The role of asbestos as a possible cause of EGFR mutagenesis requires further investigation. Am. J. Ind. Med. 60:306-309, 2017. © 2017 Wiley Periodicals, Inc.

Metastatic Breast Cancer With ESR1 Mutation: Clinical Management Considerations From the Molecular and Precision Medicine (MAP) Tumor Board at Massachusetts General Hospital.

UNLABELLED: : The last decade in oncology has witnessed impressive response rates with targeted therapies, largely because of collaborative efforts at understanding tumor biology and careful patient selection based on molecular fingerprinting of the tumor. Consequently, there has been a push toward routine molecular genotyping of tumors, and large precision medicine-based clinical trials have been launched to match therapy to the molecular alteration seen in a tumor. However, selecting the "right drug" for an individual patient in clinic is a complex decision-making process, including analytical interpretation of the report, consideration of the importance of the molecular alteration in driving growth of the tumor, tumor heterogeneity, the availability of a matched targeted therapy, efficacy and toxicity considerations of the targeted therapy (compared with standard therapy), and reimbursement issues. In this article, we review the key considerations involved in clinical decision making while reviewing a molecular genotyping report. We present the case of a 67-year-old postmenopausal female with metastatic estrogen receptor-positive (ER+) breast cancer, whose tumor progressed on multiple endocrine therapies. Molecular genotyping of the metastatic lesion revealed the presence of an ESR1 mutation (encoding p.Tyr537Asn), which was absent in the primary tumor. The same ESR1 mutation was also detected in circulating tumor DNA (ctDNA) extracted from her blood. The general approach for interpretation of genotyping results, the clinical significance of the specific mutation in the particular cancer, potential strategies to target the pathway, and implications for clinical practice are reviewed in this article. KEY POINTS: ER+ breast tumors are known to undergo genomic evolution during treatment with the acquisition of new mutations that confer resistance to treatment.ESR1 mutations in the ligand-binding domain of ER can lead to a ligand-independent, constitutively active form of ER and mediate resistance to aromatase inhibitors.ESR1 mutations may be detected by genomic sequencing of tissue biopsies of the metastatic tumor or by sequencing the circulating tumor cells or tumor DNA (ctDNA).Sequencing results may lead to a therapeutic "match" with an existing FDA-approved drug or match with an experimental agent that fits the clinical setting.

Immune Infiltration in Tumor and Adjacent Non-Neoplastic Regions Codetermines Patient Clinical Outcomes in Early-Stage Lung Cancer.

INTRODUCTION: In recent years, the proportion of patients with NSCLC diagnosed at an early stage has increased continuously. METHODS: In this study, we analyzed samples and data collected from 119 samples from 67 early stage patients with NSCLC, including 52 pairs of tumor and adjacent non-neoplastic samples, and performed RNA-sequencing analysis with high sequencing depth. RESULTS: We found that immune-related genes were highly enriched among the differentially expressed genes and observed significantly higher inferred immune infiltration levels in adjacent non-neoplastic samples than in tumor samples. In survival analysis, the infiltration of certain immune cell types in tumor, but not adjacent non-neoplastic, samples were associated with overall patient survival, and excitingly, the differential infiltration between paired samples (tumor minus non-neoplastic) was more prognostic than expression in either non-neoplastic or tumor tissues. We also performed B cell receptor (BCR) and T cell receptor (TCR) repertoire analysis and observed more BCR/TCR clonotypes and increased BCR clonality in tumor than in non-neoplastic samples. Finally, we carefully quantified the fraction of the five histologic subtypes in our adenocarcinoma samples and found that higher histologic pattern complexity was associated with higher immune infiltration and low TCR clonality in the tumor-proximal regions. CONCLUSIONS: Our results indicated significantly differential immune characteristics between tumor and adjacent non-neoplastic samples and suggested that the two regions provided complementary prognostic values in early-stage NSCLCs.

Heterogeneous immunogenicity of SARS-CoV-2 vaccines in cancer patients receiving radiotherapy.

The immunogenicity of SARS-CoV-2 vaccines in cancer patients receiving radiotherapy is unknown. This prospective cohort study demonstrates that anti-SARS-CoV-2 spike antibody and neutralization titers are reduced in a subset of thoracic radiotherapy patients, possibly due to immunosuppressive conditions. Antibody testing may be useful to identify candidates for additional vaccine doses.

Combination of PI3K/mTOR inhibition demonstrates efficacy in human chordoma.

BACKGROUND: Chordomas are rare tumors of the axial skeleton for which surgical resection remains the most reliable means of cure. PI-103 is a inhibitor of PI3K/AKT and mTOR activation. This study aims to determine whether the PI3K/mTOR pathway was active in chordomas and whether their inhibition could lead to decreased proliferation and increased apoptosis. MATERIALS AND METHODS: Thirteen human chordoma were tested for activation of the PI3K/mTOR pathway. The human chordoma cell line UCH-1 was treated with increasing doses of PI-103. Inhibition of AKT and mTOR was examined and assays assessing proliferation and apoptosis were performed. RESULTS: The chordoma specimen demonstrated activation of the PI3K/mTOR pathway. PI-103 inhibited the AKT and mTOR activation in the UCH-1 cell line. PI-103 inhibited proliferation and induced apoptosis in UCH-1. CONCLUSION: The PI3K/AKT and mTOR signaling pathway is constitutively activated in chordoma. PI-103 decreases proliferation and induces apoptosis in the UCH-1 via inhibition of the PI3K/mTOR pathway.

Clinical Grade "SNaPshot" Genetic Mutation Profiling in Multiple Myeloma.

Whole genome sequencing studies have identified several oncogenic mutations in multiple myeloma (MM). As MM progresses, it evolves genetically underscoring the need to have tools for rapid detection of targetable mutations to optimize individualized treatment. Massachusetts General Hospital (MGH) has developed a Clinical Laboratory Improvement Amendments (CLIA)-approved, high-throughput, genotyping platform to determine the mutation status of a panel of known oncogenes. Sequence analysis using SNaPshot on DNA extracted from bone marrow and extramedullary plasmacytomas is feasible and leads to the detection of potentially druggable mutations. Screening MM patients for somatic mutations in oncogenes may provide novel targets leading to additional therapies for this patient population.

The impact of EGFR mutation status on outcomes in patients with resected stage I non-small cell lung cancers.

BACKGROUND: Mutations of the epidermal growth factor hormone receptor (EGFR) gene have been associated with improved treatment response and prognosis in advanced non-small lung cancer (NSCLC). However, their prognostic role in early-stage NSCLC is not well defined. In this study we sought to identify the pure prognostic role of EGFR mutation in patients with completely resected stage I NSCLC who received no adjuvant therapy. METHODS: Mutation status was tested in treatment-naïve patients who had complete resection of stage I (T1-2aN0) NSCLC (from 2004 to 2011) using direct sequencing or multiplex polymerase chain reaction-based assay. Recurrence rates, disease-free survival, and overall survival were compared between EGFR-mutant and wild-type patients using Kaplan-Meier methods and Cox regression models. RESULTS: Three hundred seven patients were included in this study; 62 harbored tumors with EGFR mutations and 245 had wild-type EGFR. Tumors in patients with EGFR mutations were associated with a significantly lower recurrence rate (9.7% versus 21.6%; p=0.03), greater median disease-free survival (8.8 versus 7.0 years; p=0.0085), and improved overall 5-year survival (98% versus 73%; p=0.003) compared with wild-type tumors. Lobectomy was the most frequently performed procedure, accounting for 209 of 307 operations. Among these patients, EGFR mutation was associated with superior overall survival (hazard ratio, 0.45; 95% confidence interval, 0.13 to 0.83; p=0.017), with an estimated 5-year survival of 98% versus 70%. The presence of EGFR mutation (p=0.026) and tumor size less than 2 cm (p=0.04) were identified as independent prognostic markers for disease-free survival, whereas age, sex, and smoking status were not. CONCLUSIONS: Completely resected stage I EGFR mutation-positive NSCLC patients have a significant survival advantage compared with EGFR wild-type patients. Mutation of the EGFR gene is a positive prognostic marker in completely resected stage I NSCLC.

Differential expression of microRNA (miRNA) in chordoma reveals a role for miRNA-1 in Met expression.

Emerging evidence suggests that microRNA (miRNA) expression signatures in cancer may have important diagnostic, prognostic, and therapeutic value, but there is no data on miRNA expression in chordoma. The purpose of this study was to identify the role of miRNAs in human chordoma. We analyzed miRNA expression in chordoma-derived cell lines and chordoma tissue by using miRNA microarray technology with unsupervised hierarchical clustering analysis. The relative expression levels of these miRNAs were confirmed by real-time quantitative RT-PCR and Northern blot analysis. To characterize the potential role of miRNA-1, miRNA-1 was stably transfected into a chordoma cell line, UCH1. The expression of miRNA-1 targeted gene Met in chordoma tissues was also studied. We observe that human chordoma tissues and cell lines can be distinguished from normal muscle tissue by comparing miRNA expression profiles. Several miRNAs were differentially expressed in chordoma cell lines compared to controls, and similar expression patterns were found in primary chordoma tissues. Importantly, we were able to show for the first time, to our knowledge, that expression of miRNA-1 and miRNA-206, two miRNAs implicated in a number of other cancer types, were markedly decreased in both chordoma tissues and cell lines. When chordoma cell lines were transfected with miRNA-1, downregulation of known miRNA-1 targets was observed. These targets included Met and HDAC4-two genes that were observed to be overexpressed in chordoma. Our results demonstrate that some miRNAs are differentially expressed in chordoma and, in particular, miRNA-1 may have a functional effect on chordoma tumor pathogenesis.

Characterization and analysis of human chordoma cell lines.

STUDY DESIGN: An experimental study to investigate the characterization of 3 chordoma cell lines. OBJECTIVE: To characterize chordoma cell lines and generate hypothesis for further chordoma studies. SUMMARY OF BACKGROUND DATA: Three cultured human chordoma cell lines have been successfully generated; however, their characterization is incomplete. Complete characterization of chordoma cell lines is necessary for these reagents to be a useful preclinical model. METHODS: Three chordoma cell lines, CH 8, U-CH1, and GP 60, were cultured in different commercially available tissue culture media. They were also cultured in different environments, which included collagen substrate, various concentrations of glucose, and various levels of hypoxic conditions. The rate of cell proliferation was assessed by either MTT or numeration assay. A 3-dimensional (3D) cell culture model of these chordoma cell lines was also studied, and the expression of vimentin and cytokeratin was measured by immunofluorescence and Western blot. Additionally, the sensitivity of the 3 chordoma cell lines to 6 chemotherapeutic drugs was analyzed. RESULTS: CH 8, GP 60, and U-CH1 cells proliferate more actively in Iscove Modified Dulbecco Medium or Dulbecco modified Eagle Medium and less actively in RPMI medium. All 3 chordoma cell lines universally grow better in collagen substrate and survive in hypoxic conditions, whereas glucose concentration has no significant influence on their growth properties. Chordoma cell lines grew well in 3D culture systems and formed acini-like spheroids and retained the expression of vimentin and cytokeratin. MTT analysis indicates that all 3 chordoma cell lines are sensitive to doxorubicin, yondelis, zalypsis, and cisplatin. CONCLUSION: We characterized 3 chordoma cell lines for differential growth properties in a variety of media and response to chemotherapeutic agents.