Final Report: Lasques Research Mission — TNBC Drug-Selectivity Screen on the Zenodo GDSCv2 Mirror
Summary
The mission executed the end-to-end TNBC-vs-other drug-selectivity screen that iteration 1 left unfinished, using Range-chunked streaming of the 533 MB recalculated drug-response table. Two screens were run with different comparison sets: a 4-vs-963 pan-cancer screen (4 canonical TNBC lines vs all other lines) and a 9-vs-9 within-breast screen (9 TNBC vs 9 non-TNBC breast lines), both with Welch t-tests and BH-FDR. The headline biological result is a negative one: with 4 TNBC lines, zero of 206 GDSCv2 drugs survive BH-FDR at q<0.05, while the within-breast design yields 7 hits at q<0.10 (led by mk-1775/adavosertib, a WEE1 inhibitor) — meaning significance is comparison-set-dependent, and no hit can currently be called TNBC-selective. Alongside this, three statistical findings emerged: Welch+BH is anti-conservative in 4-vs-N imbalanced designs (up to 40% of all-null screens produce a false hit), a jackknife sign-flip law logit(P_flip) = -2.16 − 0.41|t|, and the observation that the top extreme-p hit (nutlin-3a) fails PRISM replication — a live demonstration of the variance-collapse mechanism. All results are exploratory; no preregistration was completed.
Key results
All findings are exploratory (run-based evidence; no confirmed preregistrations exist — the preregistration list is empty).
- Zero 4-line TNBC-selective drugs (exploratory, reproduced across seeds). Streaming the full GDSCv2 AUC matrix (206 drugs × 967 lines; runs 7568ba9f, 49a69ac9): 0 drugs at BH q<0.05 in either direction. Published as d499b464, confirmation level candidate, novelty possibly_new.
- Within-breast 9-vs-9 screen: 7 TNBC-selective hits at q<0.10 (runs d2456c8f, 942f96c8; finding e24a5361, level reproduced, novelty possibly_new): mk-1775 (adavosertib, WEE1; q=3.2e-4, Cohen's d=−2.26), azd7762 (CHK1/2; q=0.032), bortezomib (q=0.051), crizotinib (q=0.067), abt-737, bms-536924, yk-4-279. All 7 are 100% jackknife-retention stable (jobs ccf76a95, 61c208d6, 8d9fcbcf). Only 1 hit at q<0.05 (mk-1775, q≈0.049 in run a0df4a62), 0 at q<0.10 under the alternative metric variant.
- Significance is comparison-set-dependent. The same TNBC lines give 0 hits vs 963 comparators but 7 hits vs 9 non-TNBC breast comparators — the 4-line screen tests pan-cancer selectivity, not within-breast TNBC selectivity.
- Welch+BH anti-conservativeness in imbalanced designs (H3, confirmed by simulation; finding bd3d97a1, candidate, possibly_new). All-null 4-vs-300 simulations: 40% of 200-drug screens yield ≥1 false q<0.05 hit (vs 0% with permutation p-values; job 421b1e85). Large-scale all-null tests (jobs 2434d812, c52c209c, 4abb5f03): mean FDP = 1.0 at 4-vs-30 and 4-vs-300, 0.33 at 8-vs-30 — up to 20× nominal alpha. Mechanism: rare near-zero-variance small clusters collapse Welch df, producing ~1000×-enriched extreme p-values (mean 0.2 p<1e-6 per 200 tests) that pass pooled KS uniformity (p=0.17).
- Jackknife sign-flip law (finding 3e600501, candidate, possibly_new). logit(P_flip) = −2.158 − 0.408·|t| (194 drugs, held-out RMSE 0.198, job 44918e53); 40% of drugs flip sign at least once under one TNBC-line deletion; P(flip)=0.5 requires |t|≈6.5, unattainable with n=4.
- PRISM counter-screen fails structurally. The GDSCv2|PRISM reproducibility floor is Spearman r=0.524 (95% CI 0.515–0.532, AUC). Zero of the 7 within-breast hits overlap PRISM breast-tested drugs (jobs ccf76a95 etc.), so no independent confirmation exists. The single overlapping case, nutlin-3a (TNBC-resistant, q=0.0007), replicates directionally in PRISM (Δ +0.097, p<0.001) in the 9-vs-9 analysis (job 6e829cf6) but fails PRISM in the 4-vs-N design (p=0.67) with a Δ (0.05 AUC) below the floor (job 8f980e7b, finding 70b20268).
- Basal-lineage confound (H1) unmeasurable at hit level. Median basal-explained fraction ≈ 0 (−0.002) in the 4-line screen (runs 7568ba9f/49a69ac9) because there are no significant hits to explain; it remains unquantified for the 9-vs-9 hits.
What did not work
- The 4-line pan-cancer screen as a discovery design: zero q<0.05 hits across 206 drugs, and the sign-flip law shows no 4-line statistic is sign-stable. The design is underpowered by construction, not by execution.
- Cross-dataset confirmation of any hit: the PRISM subset on this mirror has essentially no drug/line overlap with the hit list (only 3 breast-overlapping drugs), so confirmation is structurally impossible with these data.
- Standard FDR diagnostics: pooled KS uniformity checks (p=0.17) do not detect the Welch variance-collapse problem; this diagnostic approach failed to flag the anti-conservativeness that permutation testing exposed.
- H1 (basal confound) at discovery level: no significant hits in the 4-line screen means the confound cannot be quantified there; it was not yet quantified for the 9-vs-9 hits either.
- Untested for lack of a completed run: docking triage and the pan-essential-gene filter never started (no DepMap context document was attached during the mission), and the H4 non-oncology enrichment hypergeometric test was not run.
Confidence and limitations
- All results are computational and exploratory; no finding reaches statistically_confirmed or formally_proven status, and no preregistration was evaluated (the preregistration list is empty).
- Novelty labels are possibly_new — meaning no close prior work was found in the checked literature set, not that the findings are proven new.
- Effect sizes of all hits (AUC Δ 0.03–0.16) are of the same order as the GDSCv2|PRISM cross-dataset noise floor (Spearman ≈ 0.52), so no claim of selectivity should be made without independent replication.
- The 9-vs-9 hit list (adavosertib, CHK1/2 inhibition, proteasome inhibition) involves mechanisms already clinically flagged in TNBC, so the biological novelty is limited; the statistical methodology findings are the more novel outputs.
- Wet-lab validation needed: adavosertib (WEE1) selectivity in the 9-line breast panel; permutation-p-value re-screen of the hit list; basal-vs-luminal stratification of the comparator group.
Next steps
- Re-run the 9-vs-9 screen with permutation p-values instead of Welch p-values (the mechanism study shows this restores FDR control) before trusting the q-value ranking.
- Quantify the basal-lineage confound for the 7 within-breast hits using the subtype table.
- Extend the sign-flip law to n_TNBC = 5–26 lines and test generality on PRISM/CTRP.
- Obtain a PRISM/CTRP subset with actual drug overlap (nutlin-3a shows replication is detectable when overlap exists) or wet-lab validate adavosertib in the 9-line panel.
- Preregister the mk-1775 selectivity claim with fixed line assignments and permutation-based statistics so it can be formally confirmed or rejected.
- Attach the DepMap Chronos matrix (researcher download) and run the pan-essential gene filter and docking triage, which never started.