From:  Targeting tumor transition windows

 Proposed evidence criteria for identifying tumor transition windows.

Evidence criterionWhat it demonstratesExamples of measurable readoutsMain limitation
Temporal evidenceShows that the state changes over time rather than reflecting a static tumor featureSerial biopsy, time-course single-cell profiling, longitudinal ctDNA/cfDNA dynamics, repeated imagingSampling frequency may miss short-lived states
Molecular-state evidenceIdentifies therapy-induced changes in tumor-cell programsTranscriptomic states, chromatin accessibility, DNA methylation, proteomic changes, metabolic markersMolecular change alone does not prove vulnerability
Functional dependency evidenceLinks the transition state to altered survival requirementsDrug-sensitivity testing, pathway inhibition, synthetic lethality assays, metabolic dependency testingOften requires experimental validation beyond profiling
Trajectory evidenceDistinguishes reversible adaptation from stable resistancePersister-state markers, clonal expansion, resistance mutations, epigenetic stabilization signaturesBoundaries between reversible and stabilized states may be gradual
Clinical detectability evidenceIndicates whether the window could be monitored in patientsctDNA, cfDNA methylation, fragmentomics, CTCs, imaging biomarkers, integrated biomarker panelsClinical thresholds and timing remain incompletely standardized
Therapeutic actionability evidenceSupports intervention during the windowSequential therapy response, adaptive therapy trials, biomarker-guided treatment modificationRequires prospective clinical validation

CTCs: circulating tumor cells; ctDNA: circulating tumor deoxyribonucleic acid.