1stOncology™: Cancer Intelligence Service – Page 16597 – 1stOncology is recognized as a Top 10 Global Pharma Analytic Provider

Computationally Designed Bispecific Antibodies using Negative State Repertoires.

A challenge in the structure-based design of specificity is modeling the negative states, i.e., the complexes that you do not want to form. This is a difficult problem because mutations predicted to destabilize the negative state might be accommodated by small conformational rearrangements. To overcome this challenge, we employ an iterative strategy that cycles between sequence design and protein docking in order to build up an ensemble of alternative negative state conformations for use in specificity prediction. We have applied our technique to the design of heterodimeric CH3 interfaces in the Fc region of antibodies. Combining computationally and rationally designed mutations produced unique designs with heterodimer purities greater than 90%. Asymmetric Fc crystallization was able to resolve the interface mutations; the heterodimer structures confirmed that the interfaces formed as designed. With these CH3 mutations, and those made at the heavy-/light-chain interface, we demonstrate one-step synthesis of four fully IgG-bispecific antibodies.
Copyright © 2016 Elsevier Ltd. All rights reserved.

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

Schedule Your 30 min Free Demo!

GTF2E2 Mutations Destabilize the General Transcription Factor Complex TFIIE in Individuals with DNA Repair-Proficient Trichothiodystrophy.

The general transcription factor IIE (TFIIE) is essential for transcription initiation by RNA polymerase II (RNA pol II) via direct interaction with the basal transcription/DNA repair factor IIH (TFIIH). TFIIH harbors mutations in two rare genetic disorders, the cancer-prone xeroderma pigmentosum (XP) and the cancer-free, multisystem developmental disorder trichothiodystrophy (TTD). The phenotypic complexity resulting from mutations affecting TFIIH has been attributed to the nucleotide excision repair (NER) defect as well as to impaired transcription. Here, we report two unrelated children showing clinical features typical of TTD who harbor different homozygous missense mutations in GTF2E2 (c.448G&gt;C [p.Ala150Pro] and c.559G&gt;T [p.Asp187Tyr]) encoding the beta subunit of transcription factor IIE (TFIIEβ). Repair of ultraviolet-induced DNA damage was normal in the GTF2E2 mutated cells, indicating that TFIIE was not involved in NER. We found decreased protein levels of the two TFIIE subunits (TFIIEα and TFIIEβ) as well as decreased phosphorylation of TFIIEα in cells from both children. Interestingly, decreased phosphorylation of TFIIEα was also seen in TTD cells with mutations in ERCC2, which encodes the XPD subunit of TFIIH, but not in XP cells with ERCC2 mutations. Our findings support the theory that TTD is caused by transcriptional impairments that are distinct from the NER disorder XP.
Copyright © 2016 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Lymphocytosis after treatment with dasatinib in chronic myeloid leukemia: Effects on response and toxicity.

The proliferation of clonal cytotoxic T-cells or natural killer cells has been observed after dasatinib treatment in small studies of patients with chronic myeloid leukemia (CML).
The incidence of lymphocytosis and its association with response, survival, and side effects were assessed in patients from 3 large clinical trials. Overall, 1402 dasatinib-treated patients with newly diagnosed CML in chronic phase (CML-CP), CML-CP refractory/intolerant to imatinib, or with CML in accelerated or myeloid-blast phase were analyzed.
Lymphocytosis developed in 32% to 35% of patients and persisted for &gt;12 months. This was not observed in the patients who received treatment with imatinib. Dasatinib-treated patients in all stages of CML who developed lymphocytosis were more likely to achieve a complete cytogenetic response, and patients who had CML-CP with lymphocytosis were more likely to achieve major and deep molecular responses. Progression-free and overall survival rates were significantly longer in patients with CML-CP who were refractory to or intolerant of imatinib and had lymphocytosis. Pleural effusions developed more commonly in patients with lymphocytosis.
Overall, lymphocytosis occurred and persisted in many dasatinib-treated patients in all phases of CML. Its presence was associated with higher response rates, significantly longer response durations, and increased overall survival, suggesting an immunomodulatory effect. Prospective studies are warranted to characterize the functional activity of these cells and to assess whether an immunologic effect against CML is detectable. Cancer 2016. © 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.
© 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

Safety and Tolerability of Linagliptin in Patients With Type 2 Diabetes: A Comprehensive Pooled Analysis of 22 Placebo-controlled Studies.

Dipeptidyl peptidase (DPP)-4 inhibitors are an increasingly used antihyperglycemic therapy for patients with type 2 diabetes mellitus (T2DM). Linagliptin, an orally administered DPP-4 inhibitor, has demonstrated favorable efficacy/safety in clinical trials. The aim of this post hoc pooled analysis was to expand current knowledge of the safety of linagliptin.
Safety data for once-daily linagliptin 5 mg (1 study of linagliptin 2.5 mg twice daily) were analyzed from 22 randomized, double-blind, Phase I-III, placebo-controlled clinical trials of ≤102 weeks’ duration. Assessments of pooled data included incidence of patient-reported adverse events (AEs).
Data from 7400 patients (linagliptin, 4810; placebo, 2590) were pooled. Most patients (58.4%) had T2DM diagnosis for &gt;5 years; approximately 75% were receiving ≥1 type of background therapy in addition to linagliptin/placebo. Overall exposure to the study drug was 2412.8 years for linagliptin and 1481.4 years for placebo (mean [SD], 183 [120] days and 209 [150] days, respectively). Overall frequencies of AEs were similar for linagliptin- and placebo-treated patients (57.3% and 61.8%, respectively). The incidence of neoplastic AEs was low (0.6% and 0.9%, respectively); there were no reports of pancreatic neoplasia. Pancreatitis was observed in 2 linagliptin-treated patients (&lt;0.1%) and 1 placebo-treated patient (&lt;0.1%). The occurrence of cardiac disorder AEs was similar in linagliptin- and placebo-treated patients (3.2% [n = 153] and 3.3% [n = 83], respectively); the incidence of heart failure AEs for linagliptin- and placebo-treated patients was 0.2% (n = 11) and 0.3% (n = 7), respectively. Overall, linagliptin was weight neutral. Occurrence of investigator-defined hypoglycemic AEs was low for both linagliptin and placebo (11.5% vs 14.0%). In patients receiving concomitant sulfonylurea therapy, investigator-defined hypoglycemic AEs were more frequent with linagliptin versus placebo (22.1% [238/1079] vs 14.5% [61/421], respectively). Subgroup analyses showed similar frequencies of AEs for linagliptin- and placebo-treated patients across different age groups and renal function levels.
This updated and expanded pooled, post hoc analysis of 22 placebo-controlled trials of linagliptin 5 mg daily supports previous findings of the acceptable overall safety/tolerability profile of linagliptin when administered to a broad range of patients with T2DM. Linagliptin-treated patients demonstrated a low overall risk of hypoglycemia (risk increased by concomitant sulfonylurea therapy). As with all pooled analyses, this study is limited by the use of data from different studies, and the relatively short duration of some included studies, although use of individual patient data from consistently designed trials should minimize methodological differences between trials. Results from ongoing clinical trials will provide additional insight into the long-term safety/tolerability of linagliptin.
Copyright © 2014 The Authors. Published by EM Inc USA.. All rights reserved.

Regulation of protein quality control by UBE4B and LSD1 through p53-mediated transcription.

Protein quality control is essential for clearing misfolded and aggregated proteins from the cell, and its failure is associated with many neurodegenerative disorders. Here, we identify two genes, ufd-2 and spr-5, that when inactivated, synergistically and robustly suppress neurotoxicity associated with misfolded proteins in Caenorhabditis elegans. Loss of human orthologs ubiquitination factor E4 B (UBE4B) and lysine-specific demethylase 1 (LSD1), respectively encoding a ubiquitin ligase and a lysine-specific demethylase, promotes the clearance of misfolded proteins in mammalian cells by activating both proteasomal and autophagic degradation machineries. An unbiased search in this pathway reveals a downstream effector as the transcription factor p53, a shared substrate of UBE4B and LSD1 that functions as a key regulator of protein quality control to protect against proteotoxicity. These studies identify a new protein quality control pathway via regulation of transcription factors and point to the augmentation of protein quality control as a wide-spectrum antiproteotoxicity strategy.