Abstract 209: A quantitative analysis of paclitaxel-induced mitotic catastrophe of MDA-MB-231 cells by high frequency ultrasound
Bibliographic record
Abstract
Abstract In recent years, high-frequency ultrasound (HFUS) has shown promise of non-invasively detecting tumor death in response to chemotherapy. However, those studies have been limited to ultrasound B-mode and immunohistochemical image comparison over extended periods of time (≥24 hours). The purpose of this study was to evaluate the relationship of quantified HFUS spectral parameters to the dynamics of tumor cell death in MDA-MB-231 cell samples exposed to paclitaxel chemotherapy. Several ultrasound parameters were investigated, including the, attenuation, spectral slope, spectral y-intercept, midband fit, estimated scatterer diameter and estimated scatterer concentration. Changes in these spectral-based parameters were evaluated in their capacity to respond to various cell death events, including mitochondrial depolarization, caspase activation, phosphatidylserine exposition, and membrane selective permeability compromise, as determined by flow cytometry analysis. Standard histology and transmission electron microscopy (TEM) permitted further investigation of possible candidates responsible for the changes detected using ultrasound. Based on TEM, negative TUNEL staining, and cell cycle analysis it was found that paclitaxel at 1mM induces mitotic catastrophe as the main cell death modality. The spectral slope correlated strongly (r2 = 0.89) with the percentage of cells arrested at the G2/M checkpoint and exhibited an opposite trend to that of systems undergoing classical apoptosis, suggesting that it may be a prime biophysical marker for differentiating modalities of tumor cell death. Midband fit increases through time suggested an increase in the concentration of acoustic scatterers. The formation of condensed chromatin condensates of a 1 micron or greater diameter in the course of paclitaxel-induced mitotic catastrophe, as revealed by TEM, were hypothesized to act as large intracellular scatterers and correlated with the increase in ultrasound midband fit. Midband fit showed the strongest correlation of all parameters (r2 = 0.99) when plotted against the percentage of the cell population expected to possess these scattering structures, establishing the first quantitative correlation of ultrasound parameters to a cell death index. These findings support that HFUS spectral parameters may be used to quantify the degree of cell death and predict the efficacy of chemotherapeutic treatment within a short post-treatment timeframe. Citation Format: Maurice M. Pasternak, Gregory J. Czarnota. A quantitative analysis of paclitaxel-induced mitotic catastrophe of MDA-MB-231 cells by high frequency ultrasound. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 209. doi:10.1158/1538-7445.AM2015-209
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 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 | 0.001 | 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 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".