BAK LOF abolishes FOXO4-DRI SC kill ≥ navitoclax on matched culture
STATUS_LABEL: NEGATIVE
polarity: negative swarm_id: P13 card_sha256: 6a29eb82b7927fc510d7fd91009ed2e407afdc61d22f7dd4b3bcdfd5e55ef56d risk_class: research-discussion note: PASS_NEGATIVE — shipped as discussion (not claim/hypothesis). Soft-complete FOXO4-DRI∩BAK LOF/epistasis/navitoclax H2H empty; matched BAK H2H remains UNKNOWN. P5–P12 are not BAK sister-pore proof.
Claim
On a matched senescent culture, BAK (Bcl-2 homologous antagonist/killer; Bak1) loss-of-function (or BAK block) abolishes FOXO4-DRI senescent-cell kill at least as completely as it abolishes navitoclax kill — pre-registered relative kill loss_FOXO4 ≥ relative kill loss_navitoclax, with each arm showing a pre-registered ≥20% relative kill loss vs the same senolytic on control genotype / vehicle.
Why it matters
Sister multi-domain effector pore after Bax (P7/P8), apoptosome/caspase-9 (P9), caspase-8 (P10), caspase-3 (P11), and BID (P12): if BAK block abolishes FOXO4-DRI ≥ navitoclax, BAK-containing MOMP is shared; if FOXO4-DRI survives while navitoclax falls, FOXO4-DRI retains BAK-sparing routes (including Bax compensation). Soft-claims: discussion — FOXO4-DRI∩BAK LOF/epistasis/navitoclax H2H soft-complete 0; sole related FOXO4-DRI apoptosis hit 41625068 cascade; matched BAK H2H remains UNKNOWN. P5–P12 are not proof of this BAK gate; P7/P8 Bax ≠ BAK isoform complement.
Mechanism sketch
FOXO4-DRI enters via FOXO4–p53; navitoclax via Bcl-2/Bcl-xL/Bcl-w; both may still require BAK as a multi-domain effector pore into MOMP — or FOXO4-DRI may stay partially BAK-independent (Bax compensation) while navitoclax is abolished (or the reverse). Endothelial FOXO4-DRI work frames a p53 / BCL-2 / Caspase-3 cascade without a BAK LOF vs navitoclax matched abolish panel. Wei classical BAX/BAK gateway prior — doubly deficient cells resist tBID / multiple mitochondrial stimuli — is not a FOXO4-DRI SC H2H. Assumption-kill: ≥ equal abolish under BAK LOF is stronger than “both can use multi-domain effectors,” and is distinct from Bax / apoptosome / caspase-8 / caspase-3 / BID necessity.
Prior art
- PMID 28340339 / DOI 10.1016/j.cell.2017.02.031 / PMC5556182 — FOXO4-DRI perturbs FOXO4–p53 → senescent-cell apoptosis (Baar 2017); not Bcl-xL occupancy; no BAK LOF arm.
- PMID 41625068 / DOI 10.3389/fbioe.2025.1729166 / PMC12852416 — endothelial FOXO4-DRI framed via p53 / BCL-2 / Caspase-3 (2025); cascade ≠ BAK LOF vs navitoclax H2H.
- PMID 26711051 / DOI 10.1111/acel.12445 / PMC4854923 — navitoclax senolytic via Bcl-2 / Bcl-xL / Bcl-w; cell-type restricted (Zhu 2016).
- PMID 11326099 / DOI 10.1126/science.1059108 / PMC3049805 — BAX and BAK are a requisite gateway to mitochondrial dysfunction and death (Wei 2001) — classical MOMP prior, not FOXO4-DRI SC matched panel.
Baseline claimed
BAK (sister multi-domain effector pore) LOF or block abolishes FOXO4-DRI SC kill ≥ navitoclax on matched SC cultures (or P5–P12 Bax/apoptosome/caspase/BID framing already settles full MOMP-execution identity).
Baseline measured
FOXO4–p53 entry LITERATURE (PMID 28340339). Downstream BCL-2/caspase-3 framing LITERATURE without BAK LOF H2H (PMID 41625068). Navitoclax Bcl-2-family senolytic LITERATURE (PMID 26711051). Wei BAX/BAK gateway LITERATURE as classical MOMP prior (PMID 11326099). Matched BAK LOF × FOXO4-DRI vs navitoclax % kill abolish UNKNOWN (soft-complete FOXO4-DRI∩BAK∩(LOF|epistasis|navitoclax) = 0; sole related FOXO4-DRI apoptosis hit = 41625068 cascade). ≥ equal abolish (loss_FOXO4 ≥ loss_nav; each ≥20% relative) PREDICTION. P5–P12 do not already prove this epistasis — P7/P8 Bax ≠ BAK.
Actionable limitations
- Do not treat P5–P12 as proving P13 — Bax / residual / apoptosome / caspase-8 / caspase-3 / BID cards did not run BAK-alone LOF; empty soft-complete ≠ demonstrated ≥ equal abolish; P7/P8 Bax ≠ BAK.
- Caspase-3 cascade ≠ BAK necessity — 41625068 implicates p53/BCL-2/Caspase-3 without genetic BAK requirement or navitoclax-matched abolish.
- Wei ≠ FOXO4-DRI panel — classical BAX/BAK gateway prior is not a senolytic H2H; ≥ equal abolish is stronger than shared multi-domain effector language; Bax may compensate under BAK-alone LOF; navitoclax-insensitive SC types confound matched culture choice.
Method
propose-assay
Prediction variables
| name | kind | assay | threshold |
|---|---|---|---|
| FOXO4_DRI_p53_entry | LITERATURE | FOXO4 peptide disrupts FOXO4–p53 in senescent cells → apoptosis (Baar 2017) | FOXO4–p53 axis entry, not Bcl-xL occupancy (PMID 28340339) |
| FOXO4_DRI_p53_BCL2_Caspase3_framing | LITERATURE | Senescent endothelium FOXO4-DRI via p53/BCL-2/Caspase-3 (2025) | mitochondrial/effector framing downstream of FOXO4–p53 (PMID 41625068) — not BAK LOF vs navitoclax H2H |
| navitoclax_Bcl2_family_senolytic | LITERATURE | ABT-263 senolysis in restricted SC panels (Zhu 2016) | Bcl-2/Bcl-xL/Bcl-w dependent; cell-type restricted (PMID 26711051) |
| Wei_BAX_BAK_MOMP_gateway_prior | LITERATURE | Cells lacking both Bax and Bak resist tBID-induced cytochrome c release and multiple mitochondrial apoptotic stimuli (Wei 2001) | classical BAX/BAK multi-domain effector gateway prior (PMID 11326099) — not FOXO4-DRI SC matched panel; no KD invented |
| matched_BAK_LOF_FOXO4_vs_navitoclax_panel | UNKNOWN | Same senescent culture — FOXO4-DRI vs navitoclax under BAK LOF or BAK block vs control; viability + MOMP/caspase readout | dedicated matched abolish panel not found (soft-complete FOXO4-DRI∩BAK∩(LOF |
| FOXO4_abolish_ge_navitoclax_under_BAK_LOF | PREDICTION | Pre-registered matched culture; relative kill loss under BAK LOF or BAK block for each senolytic vs control genotype/vehicle | relative kill loss_FOXO4 ≥ relative kill loss_navitoclax AND each arm ≥20% relative kill loss (α/N pre-specified) — do not invent observed % or dosing |
| competing_partial_BAK_independence_or_Bax_compensation | PREDICTION | Same design; falsifier path if FOXO4-DRI kill largely survives BAK LOF while navitoclax is abolished (including Bax compensation) | relative kill loss_FOXO4 below relative kill loss_navitoclax outside pre-registered ≥ equal band — BAK-sparing FOXO4-DRI / Bax compensation survives as competing outcome |
Ablate
- remove matched BAK LOF (or BAK block) contrast of FOXO4-DRI vs navitoclax on the same culture: Without the H2H abolish panel, separate LITERATURE legs cannot show FOXO4-DRI kill is abolished ≥ navitoclax under BAK LOF.
- remove ≥ equal-abolish quantitative contrast (loss_FOXO4 ≥ loss_nav): Showing both can use multi-domain effectors is weaker than the claim; FOXO4-DRI could retain partial BAK-independent / Bax-compensated routes while still “using apoptosis.”
- remove P5–P12≠proof + soft-complete-empty≠abolish + cascade-framing≠BAK-necessity + P7/P8-Bax≠BAK + Wei≠FOXO4-DRI-panel discipline: Treating P7–P12 Bax/apoptosome/caspase/BID framing or empty PubMed or 41625068 cascade or Wei classical gateway as already deciding BAK epistasis would invent a LOF result left UNKNOWN.
Refute if
On the pre-registered matched panel, FOXO4-DRI kill largely survives BAK LOF / BAK block while navitoclax kill is abolished, or relative kill loss_FOXO4 is below relative kill loss_navitoclax outside the pre-registered ≥ equal band — pathway-sparing / BAK-independent (including Bax-compensated) FOXO4-DRI execution survives.
Ask a human
Lock one senescent system sensitive to both senolytics, BAK LOF vs BAK block tool, and viability + MOMP/caspase readout before claiming ≥ equal abolish; do not treat P5–P12 as proof; P7/P8 Bax ≠ BAK; no dosing.
Cheap IP
kill_cost_tier=1 · time_to_refute=4w · ip_class=momp-execution-gate · vault_hold=no
Execution
execution_status=NOT_RUN · fto_status=UNKNOWN · related_prior=P5–P12 (Bax/apoptosome/caspase/BID ≠ BAK sister multi-domain effector pore proof; P7/P8 Bax ≠ BAK)