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Osei, E.

Publications and source records attributed to Osei, E..

3 recordsLinked to original sources

Post-treatment recovery of docetaxel-treated prostate cancer monolayer and spheroid culture

In the last half-century, it has become widely recognized that small 3D aggregates of cancer cells called tumor spheroids mimic some aspects of tumor behavior. Cell culture geometry has been shown to influence drug pharmacokinetics, delivery, and resistance. Despite the improved physiological relevance, the laborious nature of spheroids has limited clonogenic measurement and longitudinal observation of post-treatment recovery in docetaxel-treated prostate tumor spheroids. Agent-based modeling can complement spheroid experiments by probing questions of interest that are experimentally inaccessible. Here, we performed proliferation and clonogenic assays in docetaxel-treated PC3 cells cultured in monolayers and spheroids to assess and compare end-of-treatment survival and post-treatment recovery. We observed growth stimulation with no survival benefit in low dose docetaxel-treated monolayer and spheroid culture. However, agent-based modeling suggested that this hormetic effect may have been influenced by the active process of apoptosis. To the best of our knowledge, this is the first clonogenic measurement of docetaxel-treated spheroid culture and longitudinal observation of post-treatment docetaxel-dose dependent effects in prostate cancer cell culture.

cancer biology↗

Comparison of volumetric dynamic optical coherence tomography with biological methods for evaluation of radiation effects in prostate tumor spheroids

Significance3D tumor spheroids are more physiologically representative of in vivo patient tumors compared to 2D monolayer culture. However, their 3D nature challenges the use of conventional biological techniques like proliferation assays, fluorescence microscopy, and the clonogenic assay, which is the gold standard method for assessing cell survival following radiation. However, clonogenic assay requires spheroid disaggregation. AimNon-invasive volumetric imaging with dynamic optical coherence tomography (dOCT) enables cellular activity to be visualized with spatial resolution within 3D tumor spheroids. Cellular activity observed via dOCT in irradiated prostate tumor spheroids was quantified for comparison with conventional biological techniques. ApproachA Varian TrueBeam linear accelerator was used to irradiate spheroid and monolayer cultures with a 6 MV beam. Cellular activity was estimated from dOCT images generated via frequency banding and compared to clonogenic assay, proliferation assay, fluorescence microscopy, and 3D cell simulation. ResultsProstate cancer cells cultured as spheroids demonstrated improved radio-resistance via clonogenic assay compared to monolayer culture. The dOCT method demonstrated quantitative and qualitative agreement with proliferation assay and fluorescence microscopy, respectively. ConclusionsA longer duration of repeated dOCT measurement in tumor spheroids following radiation treatment could offer a non-invasive alternative to the clonogenic assay.

cancer biology↗

Longitudinal investigation of prostate tumor spheroid proliferation with dynamic line-field optical coherence tomography

Recently, it has become widely recognized that culturing cancer cells in vitro in small, 3D aggregates known as tumor spheroids provides a more physiologically relevant model of in vivo tumor behavior compared to 2D monolayer cultures. Dynamic optical coherence tomography (dOCT) is a non-invasive imaging modality that, by analyzing temporal fluctuations in the light scattered from biological tissue, does not require exogenous contrast agents to visualize and quantify cellular activity within 3D cell cultures. However, recent volumetric dOCT studies have encountered challenges due to low acquisition speeds. In this study, we present morphological and dynamic analyses of prostate tumor spheroid growth over a two-week longitudinal period, utilizing volumetric imaging with a line-field dOCT platform. Our method clearly differentiated between active cellular metabolism in live spheroids and the lack of activity in spheroids fixed with formaldehyde. Quantitative validation of the dynamic signal was conducted using the Alamar Blue proliferation assay, while qualitative validation was provided by live/dead fluorescence microscopy.

cancer biology↗