Description
The abstract shows fluoxetine has unique anti-GBM effects not seen with other SSRIs, suggesting SMPD1 inhibition is specific to fluoxetine rather than a class effect. Understanding this selectivity could guide development of more potent SMPD1 inhibitors for brain cancer therapy.
Gap type: unexplained_observation Source paper: Targeting glioblastoma signaling and metabolism with a re-purposed brain-penetrant drug. (None, None, PMID:34731610)
Resolution criteria
Resolution requires: (1) X-ray crystallography or cryo-EM of SMPD1 with fluoxetine vs control SSRIs (sertraline, citalopram) at ≥2.5 Å resolution, identifying structural basis for selectivity; (2) mutagenesis study (SMPD1 site-directed) confirming amino acids responsible for fluoxetine binding; (3) SPR/BLI measurement of binding affinity (KD) for all SSRIs to SMPD1, showing ≥10-fold fluoxetine selectivity. Docking studies alone are insufficient.
Evidence summary
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