Abstract C246: SH-4-54, a novel small-molecule inhibitor of STAT3, demonstrates significant anti-tumor activity against multiple myeloma.
Bibliographic record
Abstract
Abstract Aberrant STAT3 signaling is prevalent in hematologic malignancies such as Multiple Myeloma (MM) and is recognized as a master regulator of tumor processes such as survival, angiogenesis, and drug resistance. Significant efforts have therefore focused on therapeutic targeting of STAT3 as an anti-cancer strategy. Based on rational structure-based design, we present pre-clinical findings for a newly developed small molecule STAT3 inhibitor, SH-4-54. SH-4-54 was designed to block the SH2 domain of STAT3 by mimicking its native phosphopeptide binding sequence and in turn prevent phosphorylation (activation) and disrupt transcriptionally active STAT3:STAT3 dimerization. SH-4-54 has been shown to have a KD for STAT3 protein of 300 nM by surface plasmon resonance and inhibits STAT3 SH2 domain-phosphopeptide interactions as assessed by a fluorescence polarization assay. The anti-MM activity of SH-4-54 was assessed using MTT assays against a panel of molecularly heterogeneous human myeloma cell lines (HMCLs), revealing potent and broad effects on cell viability with 10/15 HMCLs displaying IC50 values < 10 μM. Moreover, SH-4-54 induced apoptotic responses in HMCLs as evidenced by increased Annexin V staining. Promising results were observed for the effects of SH-4-54 on primary patient-derived myeloma cells. Using flow cytometric analysis of CD138 as a marker of myeloma cells and Annexin V staining, SH-4-54 was found to significantly reduce the percentage of CD138+/Annexin V negative, viable myeloma cells, while displaying little to no toxicity against the non-malignant (CD138−) cell fraction. Supporting the predicted molecular mechanisms of SH-4-54 activity, immunoblot analysis revealed that SH-4-54 inhibits constitutive STAT3 phosphorylation, but does not alter STAT3 protein levels. Furthermore, using HMCLs engineered to express a STAT3-driven luciferase reporter construct, SH-4-54 was found to significantly reduce STAT3 transcriptional activity, and consistently induce a reduction in proteins that encode STAT3 target genes such as c-Myc. Taken together, our results highlight the promising therapeutic potential of SH-4-54 and support the continued development of targeted therapies for MM with a focus on aberrant STAT signaling. Citation Information: Mol Cancer Ther 2013;12(11 Suppl):C246. Citation Format: Zhi Hua Li, Sina Haftchenary, Danielle Croucher, Patrick T. Gunning, Suzanne Trudel. SH-4-54, a novel small-molecule inhibitor of STAT3, demonstrates significant anti-tumor activity against multiple myeloma. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr C246.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".