% nano-lazar
: A framework for nanoparticle read across risk assessment
% Christoph Helma, Micha Rautenberg, Denis Gebele
% in silico toxicology gmbh, Basel, Switzerland
Framework for reproducible read-across (k-nearest-neighbor) predictions
For a given query substance (nanoparticle)
- Find similar substances (neighbors)
- Create local model with neighbor activities
- Apply local model to predict the query substance
Free choice of algorithms and parameters for
- Descriptors (measured, calculated)
- Feature selection
- Similarity calculation
- Local QSAR models
Reasonable default algorithms and parameters
Endpoint: ~ Net cell association (121 Gold and Silver particles)
Descriptors: ~ Calculated fingerprints (new development), measured physchem properties, protein interactions
Feature selection: ~ Correlation filter (measured properties)
Similarity: ~ Weighted cosine (measured properties), Tanimoto/Jaccard (fingerprints)
Local regression: ~ Weighted average, partial least squares (PLS), random forests (RF)
- Five independent 10-fold crossvalidations
- No fixed random seed for training/test set splits, to avoid overfitting and to demonstrate the variability of validation results due to random training/test splits.
- Separate feature selection for each training dataset to avoid overfitting
Gold and silver particles included!
Correlation of predicted vs. measured values for five independent crossvalidations with Proteomics descriptors and local random forest models
- Best results: Protein interaction descriptors and random forest models
- Most results show no statistically significant difference
- Calculated fingerprints perform surprisingly well (RMSE comparable to best results) and do not require measured nanoparticle properties
- Local random forest models with nanoparticle fingerprints can be useful for screening purposes without physical measurements
![](images/nano-lazar fingerprint input.ch_predict.png){#id .class height=50%}
![](images/nano-lazar fingerprint result.ch_predict.png){#id .class height=50%}
Manuscript submitted to Frontiers in Pharmacology
- Open source code for lazar and publication
- Manuscript with direct source code links
- Docker image with
lazar
libraries- Training data
- Validation experiments
- Software dependencies
- Build system to recreate validations
- Update facilities for code and data
Nano-lazar GUI : https://nano-lazar.in-silico.ch
Lazar (source code) : https://github.com/opentox/lazar
Publication (source code) : https://github.com/opentox/nano-lazar-paper
Docker image : https://hub.docker.com/r/insilicotox/nano-lazar-paper/
Twitter ~ https://twitter.com/insilicotox
Email ~ [email protected]