Cytotoxic effects of violacein in human uveal melanoma cell lines
Bibliographic record
Abstract
Violacein is the main pigment produced by Chromobacterium violaceum, a saprophytic gram-negative bacillus. Violacein is formed by the condensation of two modified tryptophan molecules and has potential anti-neoplastic effects. The purpose of this pilot study was to investigate the in vitro activity of violacein in human uveal melanoma cell lines. Human uveal melanoma cell lines 92.1 and OCM-1 were incubated with five different concentrations of violacein (10(-5)-10(-9) M), and the total cellular protein content was measured by means of the sulphorhodamine B assay. Dose-response curves were obtained and the concentration inhibiting cell growth by 50% (IC50) together with the concentration inhibiting the net cell growth by 50% (GI50) were calculated for both cell lines. Violacein IC50 and GI50 concentrations to cell line 92.1 were 2.78 x 10(-6) M and 1.69 x 10(-6) M, respectively. The IC50 and GI50 concentrations to cell line OCM-1 were 3.69 x 10(-6) M and 2.12 x 10(-6) M, respectively. Previous studies using the same methodology have revealed violacein to have a GI50 in the range (3-6) x 10(-8) M for MOLT-4 leukaemia, NCI-H460 large cell lung cancer and KM12 colon cancer cell lines. Violacein displayed borderline cytotoxic activity in human uveal melanoma cell lines 92.1 and OCM-1, as measured by the sulphorhodamine B assay, and further studies are necessary to define its suitability as a potential therapeutic agent for metastatic uveal melanoma.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".