Chemical tumor promoters induce significant morphologic changes in several cultured cell models. In this article we describe a new effect of two potent, chemically different tumor promoters, 12-O-tetradecanoylphorbol-13-acetate (TPA) and dihydroteleocidin B (DHTB) on cultured human HeLa and melanoma cells. Using immunofluorescence microscopy, we observed that TPA and DHTB induced a dramatic increase in the size (greater than or equal to 3X normal diameter) of the centrosome, a microtubule-organizing center, within 24 h of incubation. In HeLa cells the effect was serum- and dose-dependent, was observed in 76-92% of cells within 72 h of incubation, and was associated with an increase in cytoplasm-nucleus ratio and proliferation of microtubules from the centrosome. The tumor promoters inhibited serum-induced DNA synthesis in both cell lines. Electron microscopy revealed the presence of clumps of microcentriole bodies or fragments adjacent to the intact centriole.
R N Mascardo, P Sherline
Usage data is cumulative from February 2024 through February 2025.
Usage | JCI | PMC |
---|---|---|
Text version | 77 | 0 |
41 | 17 | |
Figure | 0 | 2 |
Scanned page | 202 | 3 |
Citation downloads | 42 | 0 |
Totals | 362 | 22 |
Total Views | 384 |
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.