AI is a viable alternative to high throughput screening: a 318-target study

: High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

The Beam Chopper Power Converter for MedAustron: Safety by Design and Development

MedAustron is the Austrian centre for hadron therapy and non-clinical research. The beam chopper system is an essential component for patient safety in specific hazardous situations as well as for beam delivery from the synchrotron to the irradiation rooms. This paper presents the results from the development phase and the commissioning of the MedAustron beam chopper system. Details will be given on the design, the risk management, the test and the verification of the chopper power converter (PKC)

The value of local treatment in patients with primary, disseminated, multifocal Ewing sarcoma (PDMES)

The value of local treatment in patients with primary, disseminated, multifocal Ewing sarcoma (PDMES) was investigated. We analyzed 120 patients registered into the European Ewing Tumor Working Initiative of National Groups (EURO-E.W.I.N.G. 99) trial at the trial center of Muenster from 1998 to 2006. Median age was 16.2 years. Local treatment of the primary tumor was surgery in 26 of 120 patients, surgery and radiotherapy in 21 patients, and definitive radiotherapy in 40 patients. For treatment of metastases, 6 of 120 patients received surgery; 9 patients, surgery and radiotherapy; and 33 patients, definitive radiotherapy. Forty-seven (39%) patients had local treatment of both the primary tumor and metastases, 41 (34%) patients of either the primary tumor or metastases, and 32 (27%) received no local therapy. Event-free survival (EFS) at 3 years was 0.24 (95% CI, 0.16-0.33). Univariate analyses demonstrated the impact of local therapy given to the primary tumor: 3-year EFS was 0.25 with surgery, 0.47 with surgery and radiotherapy, 0.23 with radiotherapy, and 0.13 when no local therapy was administered (P < .001). Three-year EFS in PDMES was also influenced by the local treatment: surgery, 0.33; surgery and radiotherapy, 0.56; radiotherapy, 0.35; no local therapy, 0.16 (P = .003). Three-year EFS was 0.39 in patients who received local treatment of both primary tumor and PDMES, compared with 0.17 in patients with any local treatment of either primary tumor or PDMES and 0.14 in patients with no local therapy (P < .001). Multivariate analysis showed absence of local treatment to be the major risk factor (HR = 2.21; P = .027; n = 20). Local therapy of involved sites is important for patients with PDMES and should complement systemic treatment whenever possibl

Pediatric Patients with Stage IV Rhabdomyosarcoma Significantly Benefit from Long-Term Maintenance Therapy: Results of the CWS-IV 2002 and the CWS DOK IV 2004-Trials

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma (STS) in childhood. Whereas more than 90% of patients with localized low-risk RMS can be cured, metastatic RMS have a dismal outcome, with survival rates of less than 30%. The HD CWS-96 trial showed an improved outcome for patients receiving maintenance therapy after completing intensive chemotherapy. Consequently, the international clinical trials CWS-IV 2002 and CWS DOK IV 2004 on metastatic disease of STS of the Cooperative Weichteilsarkom Studiengruppe (CWS) were designed in addition to the CWS-2002P trial for localized RMS disease. All patients received a multimodal intensive treatment regimen. To maintain remission, three options were compared: long-term maintenance therapy (LTMT) versus allogeneic hematopoietic stem cell transplantation (alloHSCT) versus high-dose chemotherapy (HDCT). A total of 176 pediatric patients with a histologically confirmed diagnosis of metastatic RMS or RMS-like tumor were included. A total of 89 patients receiving LTML showed a significantly better outcome, with an event-free survival (EFS) of 41% and an overall survival (OS) of 53%, than alloHSCT (n = 21, EFS 19%, p = 0.02, OS 24%, p = 0.002). The outcome of LTML was slightly improved compared to HDCT (n = 13, EFS 35%, OS 34%). In conclusion, our data suggest that in patients suffering from metastatic RMS, long-term maintenance therapy is a superior strategy in terms of EFS and OS compared to alloHSCT. EFS and OS of HDCT are similar in these strategies; however, the therapeutic burden of LTMT is much lower

Structure-Guided Design of EED Binders Allosterically Inhibiting the Epigenetic Methyltransferase PRC2

PRC2 is a multisubunit methyltransferase involved in epigenetic regulation of early embryonic development and cell growth. The catalytic subunit EZH2 methylates primarily lysine 27 of histone H3, leading to chromatin compaction and repression of tumor suppressor genes. Inhibiting this activity by small molecules targeting EZH2 was shown to result in anti-tumor efficacy. Here, we describe the identification and optimization of a new class of small molecule PRC2 inhibitors that acts allosterically via the trimethyllysine pocket of the non-catalytic EED subunit. Deconstruction of a larger screening hit to a fragment-sized molecule followed by structure-guided regrowth and careful property modulation were employed to achieve sub-micromolar inhibition in functional assays and cellular activity

Structure-Guided Design of EED Binders Allosterically Inhibiting the Epigenetic Polycomb Repressive Complex 2 (PRC2) Methyltransferase

PRC2 is a multisubunit methyltransferase involved in epigenetic regulation of early embryonic development and cell growth. The catalytic subunit EZH2 methylates primarily lysine 27 of histone H3, leading to chromatin compaction and repression of tumor suppressor genes. Inhibiting this activity by small molecules targeting EZH2 was shown to result in antitumor efficacy. Here, we describe the optimization of a chemical series representing a new class of PRC2 inhibitors which acts allosterically via the trimethyllysine pocket of the noncatalytic EED subunit. Deconstruction of a larger and complex screening hit to a simple fragment-sized molecule followed by structure-guided regrowth and careful property modulation were employed to yield compounds which achieve submicromolar inhibition in functional assays and cellular activity. The resulting molecules can serve as a simplified entry point for lead optimization and can be utilized to study this new mechanism of PRC2 inhibition and the associated biology in detail