CEA/CD3 bispecific antibody MEDI-565/AMG 211 activation of T cells and subsequent killing of human tumors is independent of mutations commonly found in colorectal adenocarcinomas.
ABSTRACT: Individual or combinations of somatic mutations found in genes from colorectal cancers can redirect the effects of chemotherapy and targeted agents on cancer cell survival and, consequently, on clinical outcome. Novel therapeutics with mechanisms of action that are independent of mutational status would therefore fulfill a current unmet clinical need. Here the CEA and CD3 bispecific single-chain antibody MEDI-565 (also known as MT111 and AMG 211) was evaluated for its ability to activate T cells both in vitro and in vivo and to kill human tumor cell lines harboring various somatic mutations commonly found in colorectal cancers. MEDI-565 specifically bound to normal and malignant tissues in a CEA-specific manner, and only killed CEA positive cells. The BiTE® antibody construct mediated T cell-directed killing of CEA positive tumor cells within 6 hours, at low effector-to-target ratios which were independent of high concentrations of soluble CEA. The potency of in vitro lysis was dependent on CEA antigen density but independent of the mutational status in cancer cell lines. Importantly, individual or combinations of mutated KRAS and BRAF oncogenes, activating PI3KCA mutations, loss of PTEN expression, and loss-of-function mutations in TP53 did not reduce the activity in vitro. MEDI-565 also prevented growth of human xenograft tumors which harbored various mutations. These findings suggest that MEDI-565 represents a potential treatment option for patients with CEA positive tumors of diverse origin, including those with individual or combinations of somatic mutations that may be less responsive to chemotherapy and other targeted agents.
Project description:MEDI-565 (also known as MT111) is a bispecific T-cell engager (BiTE®) antibody in development for the treatment of patients with cancers expressing carcinoembryonic antigen (CEA). MEDI-565 binds CEA on cancer cells and CD3 on T cells to induce T-cell mediated killing of cancer cells. To understand the molecular basis of human CEA recognition by MEDI-565 and how polymorphisms and spliced forms of CEA may affect MEDI-565 activity, we mapped the epitope of MEDI-565 on CEA using mutagenesis and homology modeling approaches. We found that MEDI-565 recognized a conformational epitope in the A2 domain comprised of amino acids 326-349 and 388-410, with critical residues F(326), T(328), N(333), V(388), G(389), P(390), E(392), I(408), and N(410). Two non-synonymous single-nucleotide polymorphisms (SNPs) (rs10407503, rs7249230) were identified in the epitope region, but they are found at low homozygosity rates. Searching the National Center for Biotechnology Information GenBank® database, we further identified a single, previously uncharacterized mRNA splice variant of CEA that lacks a portion of the N-terminal domain, the A1 and B1 domains, and a large portion of the A2 domain. Real-time quantitative polymerase chain reaction analysis of multiple cancers showed widespread expression of full-length CEA in these tumors, with less frequent but concordant expression of the CEA splice variant. Because the epitope was largely absent from the CEA splice variant, MEDI-565 did not bind or mediate T-cell killing of cells solely expressing this form of CEA. In addition, the splice variant did not interfere with MEDI-565 binding or activity when co-expressed with full-length CEA. Thus MEDI-565 may broadly target CEA-positive tumors without regard for expression of the short splice variant of CEA. Together our data suggest that MEDI-565 activity will neither be impacted by SNPs nor by a splice variant of CEA.
Project description:<h4>Background</h4>Novel technologies to redirect T-cell killing against cancer cells are emerging. We hypothesised that metastatic human colorectal cancer (CRC) previously treated with conventional chemotherapy would be sensitive to T-cell killing mediated by carcinoembryonic antigen (CEA)/CD3-bispecific T-cell-engaging BiTE antibody (MEDI-565).<h4>Methods</h4>We analysed proliferation and lysis of CEA-positive (CEA+) CRC specimens that had survived previous systemic chemotherapy and biologic therapy to determine whether they could be killed by patient T cells engaged by MEDI-565 in vitro.<h4>Results</h4>At low concentrations (0.1-1 ng ml(-1)), MEDI-565+ T cells caused reduced proliferation and enhanced apoptosis of CEA+ human CRC specimens. High levels of soluble CEA did not impair killing by redirected T cells and there was no increase in resistance to T-cell killing despite multiple rounds of exposure.<h4>Conclusions</h4>This study shows for the first time that metastatic CRC specimens derived from patients previously treated with conventional chemotherapy can be lysed by patient T cells. Clinical testing of cancer immunotherapies, such as MEDI-565 that result in exposure of tumours to large numbers of T cells, is warranted.
Project description:There has been limited progress evaluating the validity of dimensional approaches to emotional disorder classification. This has occurred in part because of a lack of standardized assessment tools developed with the specific intent of studying dimensional classification. The goal of the current study was to develop and validate the Multidimensional Emotional Disorder Inventory (MEDI) to efficiently assess nine empirically supported transdiagnostic dimensions proposed in the Brown and Barlow (2009) profile approach to emotional disorder classification: neurotic temperament, positive temperament, depression, autonomic arousal, somatic anxiety, social anxiety, intrusive cognitions, traumatic reexperiencing, and avoidance. The MEDI factor structure, reliability, and convergent/discriminant validity was evaluated in outpatients with emotional disorders (pilot sample = 227; validation sample = 780). The final 9-factor solution fit the data well. Intercorrelations among MEDI factors were consistent with previous research, and all MEDI dimensions had acceptable reliability. Correlations with common self-report questionnaires and DSM-5 diagnoses supported the convergent/discriminant validity of all nine MEDI dimensions. Collectively, these results support the use of 49-item MEDI in clinical research samples. The MEDI should be used in future research to evaluate the validity of the Brown and Barlow (2009) approach to emotional disorder classification. Because it provides an efficient assessment of several well-established emotional disorder traits and phenotypes, the MEDI also may have utility for general research or clinical purposes. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Project description:Abstract Macronutrients, comprising carbohydrates, proteins and lipids, underpin many ecological processes, but their quantification in ecological studies is often inaccurate and laborious, requiring large investments of time and bulk samples, which make individual‐level studies impossible. This study presents Macronutrient Extraction and Determination from Invertebrates (MEDI), a protocol for the direct, rapid and relatively low‐cost determination of macronutrient content from single small macroinvertebrates. Macronutrients were extracted by a sequential process of soaking in 1:12 chloroform:methanol solution to remove lipid and then solubilising tissue in 0.1 M NaOH. Proteins, carbohydrates and lipids were determined by colorimetric assays from the same individual specimens. The limits of detection of MEDI with the equipment and conditions used were 0.067, 0.065 and 0.006 mg/ml for proteins, carbohydrates and lipids respectively. Adjusting the volume of reagents used for extraction and determination can broaden the range of concentrations that can be detected. MEDI successfully identified taxonomic differences in macronutrient content between five insect species. Macronutrient Extraction and Determination from Invertebrates can directly and rapidly determine macronutrient content in tiny (dry mass ~3 mg) and much larger individual invertebrates. Using MEDI, the total macronutrient content of over 50 macroinvertebrates can be determined within around 3 days of collection at a cost of ~$1.35 per sample.
Project description:<h4>Background</h4>Targeted next-generation sequencing (NGS) is frequently obtained at the University of California, Los Angeles (UCLA) for clinical characterization of CNS tumors. In this study, we describe the diagnostic reliability of the Foundation Medicine (FM) targeted NGS platform and its ability to explore and identify tumor characteristics of prognostic significance in gliomas.<h4>Methods</h4>Neuro-oncology patients seen at UCLA who have received FM testing between August 2012 and March 2019 were included in this study, and all mutations from FM test reports were recorded. Initial tumor diagnoses and diagnostic markers found via standard clinical methods were obtained from pathology reports. With overall and progression-free survival data, elastic net regularized Cox regression and Cox proportional hazards models were used to determine whether any mutations of unknown significance detected by FM could predict patient outcome in glioblastoma (GBM).<h4>Results</h4>Six hundred and three samples tested by FM from 565 distinct patients were identified. Concordance of diagnostic markers was high between standard clinical testing methods and FM. Oligodendroglial markers detected via FM were highly correlated with 1p19q codeletion in <i>IDH</i> mutated gliomas. FM testing of multiple tumor samples from the same patient demonstrated temporal and spatial mutational heterogeneity. Mutations in <i>BCORL1</i>, <i>ERBB4</i>, and <i>PALB2</i>, which are mutations of unknown significance in GBM, were shown to be statistically significant in predicting patient outcome.<h4>Conclusions</h4>In our large cohort, we found that targeted NGS can both reliably and efficiently detect important diagnostic markers in CNS tumors.
Project description:All cancers carry somatic mutations in their genomes. A subset, known as driver mutations, confer clonal selective advantage on cancer cells and are causally implicated in oncogenesis, and the remainder are passenger mutations. The driver mutations and mutational processes operative in breast cancer have not yet been comprehensively explored. Here we examine the genomes of 100 tumours for somatic copy number changes and mutations in the coding exons of protein-coding genes. The number of somatic mutations varied markedly between individual tumours. We found strong correlations between mutation number, age at which cancer was diagnosed and cancer histological grade, and observed multiple mutational signatures, including one present in about ten per cent of tumours characterized by numerous mutations of cytosine at TpC dinucleotides. Driver mutations were identified in several new cancer genes including AKT2, ARID1B, CASP8, CDKN1B, MAP3K1, MAP3K13, NCOR1, SMARCD1 and TBX3. Among the 100 tumours, we found driver mutations in at least 40 cancer genes and 73 different combinations of mutated cancer genes. The results highlight the substantial genetic diversity underlying this common disease.
Project description:Collagen IV is a family of 6 chains (?1-?6), that form triple-helical protomers that assemble into supramolecular networks. Two distinct networks with chain compositions of ?121 and ?345 have been established. These oligomerize into separate ?121 and ?345 networks by a homotypic interaction through their trimeric noncollagenous (NC1) domains, forming ?121 and ?345 NC1 hexamers, respectively. These are stabilized by novel sulfilimine (-S=N-) cross-links, a covalent cross-link that forms between Met(93) and Hyl(211) at the trimer-trimer interface. A third network with a composition of ?1256 has been proposed, but its supramolecular organization has not been established. In this study we investigated the supramolecular organization of this network by determining the chain identity of sulfilimine-cross-linked NC1 domains derived from the ?1256 NC1 hexamer. High resolution mass spectrometry analyses of peptides revealed that sulfilimine bonds specifically cross-link ?1 to ?5 and ?2 to ?6 NC1 domains, thus providing the spatial orientation between interacting ?121 and ?565 trimers. Using this information, we constructed a three-dimensional homology model in which the ?565 trimer shows a good chemical and structural complementarity to the ?121 trimer. Our studies provide the first chemical evidence for an ?565 protomer and its heterotypic interaction with the ?121 protomer. Moreover, our findings, in conjunction with our previous studies, establish that the six collagen IV chains are organized into three canonical protomers ?121, ?345, and ?565 forming three distinct networks: ?121, ?345, and ?121-?565, each of which is stabilized by sulfilimine bonds between their C-terminal NC1 domains.
Project description:This phase I, multicenter, open-label, single-arm, dose-escalation, and dose-expansion study evaluated the safety, tolerability, and antitumor activity of MEDI-573 in adults with advanced solid tumors refractory to standard therapy or for which no standard therapy exists.Patients received MEDI-573 in 1 of 5 cohorts (0.5, 1.5, 5, 10, or 15 mg/kg) dosed weekly or 1 of 2 cohorts (30 or 45 mg/kg) dosed every 3 weeks. Primary end points included the MEDI-573 safety profile, maximum tolerated dose (MTD), and optimal biologic dose (OBD). Secondary end points included MEDI-573 pharmacokinetics (PK), pharmacodynamics, immunogenicity, and antitumor activity.In total, 43 patients (20 with urothelial cancer) received MEDI-573. No dose-limiting toxicities were identified, and only 1 patient experienced hyperglycemia related to treatment. Elevations in levels of insulin and/or growth hormone were not observed. Adverse events observed in >10% of patients included fatigue, anorexia, nausea, diarrhea, and anemia. PK evaluation demonstrated that levels of MEDI-573 increased with dose at all dose levels tested. At doses >5 mg/kg, circulating levels of insulin-like growth factor (IGF)-I and IGFII were fully suppressed. Of 39 patients evaluable for response, none experienced partial or complete response and 13 had stable disease as best response.The MTD of MEDI-573 was not reached. The OBD was 5 mg/kg weekly or 30 or 45 mg/kg every 3 weeks. MEDI-573 showed preliminary antitumor activity in a heavily pretreated population and had a favorable tolerability profile, with no notable perturbations in metabolic homeostasis.
Project description:<h4>Background</h4>Targeting the cell-surface receptor EphA2, which is highly expressed in some solid tumors, is a novel approach for cancer therapy. We aimed to evaluate the safety profile, maximum tolerated dose (MTD), pharmacokinetics, and antitumor activity of MEDI-547, an antibody drug conjugate composed of the cytotoxic drug auristatin (toxin) linked to a human anti-EphA2 monoclonal antibody (1C1), in patients with solid tumors relapsed/refractory to standard therapy.<h4>Methods</h4>In this phase 1, open-label study with planned dose-escalation and dose-expansion cohorts, patients received a 1-h intravenous infusion of MEDI-547 (0.08 mg/kg) every 3 weeks.<h4>Results</h4>Six patients received 0.08 mg/kg; all discontinued treatment. Dose escalation was not pursued. The study was stopped before cohort 2 enrollment due to treatment-related bleeding and coagulation events (hemorrhage-related, n = 3; epistaxis, n = 2). Therefore, lower doses were not explored and an MTD could not be selected. The most frequently reported treatment-related adverse events (AEs) were increased liver enzymes, decreased hemoglobin, decreased appetite, and epistaxis. Three patients (50%) experienced treatment-related serious AEs, including conjunctival hemorrhage, pain (led to study drug discontinuation), liver disorder, and hemorrhage. Best response included progressive disease (n = 5; 83.3%) and stable disease (n = 1; 16.7%). Minimal or no dissociation of toxin from 1C1 conjugate occurred in the blood. Serum MEDI-547 concentrations decreased rapidly, ~70% by 3 days post-dose. No accumulation of MEDI-547 was observed at 0.08 mg/kg upon administration of a second dose 3 weeks following dose 1.<h4>Conclusions</h4>The safety profile of MEDI-547 does not support further clinical investigation in patients with advanced solid tumors.