{"entity":{"id":"idea-bio2-metastasis-screen-standard","kind":"idea","name":"Make in vivo metastasis screens a required step in drug discovery","aka":[],"tldr":"Drug candidates are tested for shrinking tumours, almost never for stopping spread. A standard spread test would find anti-metastatic drugs we are throwing away.","summary":"Barcoded in vivo CRISPR and lineage-tracing screens can quantify seeding, survival in circulation and outgrowth as separate phenotypes. Very few programmes run them, so anti-metastatic activity is invisible during discovery. Funders could require a standard metastasis panel (spontaneous metastasis from orthotopic implantation plus a barcoded seeding assay) from any grant or programme claiming anti-metastatic intent.","asOf":"2026-09-08","links":[{"label":"Bottleneck evidence (Metastasis is understood least and studied last): Dillekås et al., Are 90% of deaths from cancer caused by metastases? (Cancer Medicine 2019)","url":"https://doi.org/10.1002/cam4.2474"}],"tags":[],"related":["depmap","cancer-models"],"cancers":[],"sections":[],"technologies":["crispr-screens","pdx-models","organoids"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":["b-metastasis-biology","b-preclinical-models","b-negative-results"],"keyPapers":["paper-dillekas-cancer-med"],"journals":[],"dependsOn":[],"notes":[],"hypothesis":"Compounds active in standardised seeding and outgrowth assays but inactive in subcutaneous growth assays exist at a rate of at least 5% in current oncology libraries, and are being discarded today.","rationale":"Metastasis is a distinct set of phenotypes with distinct genetic dependencies, so screening only for proliferation systematically selects against anti-metastatic mechanisms. Barcoded clonal tracking gives quantitative, well-powered readouts from few animals.","test":"Rescreen 2,000 shelved oncology compounds from academic and industry libraries in a barcoded orthotopic seeding assay for two tumour types, and publish all hits and misses openly.","maturity":"preclinical-evidence","actor":"research","cost":"small","horizonYears":4},"route":"/ideas/idea-bio2-metastasis-screen-standard/","neighbours":{"collection":[{"id":"cancer-models","kind":"collection","name":"Cancer Models (PDCM Finder) & HCMI","route":"/collections/cancer-models/"},{"id":"depmap","kind":"collection","name":"DepMap (Cancer Dependency Map)","route":"/collections/depmap/"}],"technology":[{"id":"crispr-screens","kind":"technology","name":"CRISPR functional genomics","route":"/technologies/crispr-screens/"},{"id":"organoids","kind":"technology","name":"Patient-derived organoids","route":"/technologies/organoids/"},{"id":"pdx-models","kind":"technology","name":"Patient-derived xenografts","route":"/technologies/pdx-models/"}],"bottleneck":[{"id":"b-negative-results","kind":"bottleneck","name":"Failures are hidden","route":"/bottlenecks/b-negative-results/"},{"id":"b-preclinical-models","kind":"bottleneck","name":"Lab models that fail to predict what happens in patients","route":"/bottlenecks/b-preclinical-models/"},{"id":"b-metastasis-biology","kind":"bottleneck","name":"Metastasis is understood least and studied last","route":"/bottlenecks/b-metastasis-biology/"}],"paper":[{"id":"paper-dillekas-cancer-med","kind":"paper","name":"Are 90% of deaths from cancer caused by metastases?","route":"/key-papers/paper-dillekas-cancer-med/"}]}}