Cell cycle perturbation by sodium butyrate in tumorigenic and non‐tumorigenic human urothelial cell lines assessed by flow cytometric bromodeoxyuridine/DNA analysis

Abstract

The effect of sodium butyrate on cell proliferation was studied in eight human urothelial cell lines differing in transformation grade (TGr): Hu 1752 (mortal, TGr I); HCV29 (immortal and tumorigenic, TGr II); HCV29T, T24, T24A, T24B, Hu 961A and Hu 1703He (tumorigenic, TGr III). In all cell lines, except Hu 1752, addition of 4 mM sodium butyrate at 18 h after replating resulted in a significantly decreased population of adherent cells after a further 24-48 h. This might partially be explained by detachment of cells, probably mainly S phase cells, from the substrate in the lines HCV29, HCV 29T, Hu 961A and Hu 1703He. Flow cytometric DNA analysis of the adherent cell population showed that all TGr II and III urothelial cell lines were DNA aneuploid, and that butyrate perturbed the cell cycle distribution in these cell lines, mainly by a decrease of the S phase fraction. Flow cytometric bromodeoxyuridine (BrdUrd)/DNA analysis of continuously BrdUrd labelled cultures, using a 'washless' BrdUrd/DNA staining technique, showed that butyrate inhibited the G0/1-S phase transition, indicated by a delayed depletion of BrdUrd negative G0/1 cells in the cell lines HCV29, HCV29T, T24B, Hu 961A and Hu 1703He. BrdUrd/DNA analysis further showed that butyrate inhibited the G2M-G0/1 phase transition, indicated by a pronounced accumulation of BrdUrd positive G2M cells in the cell lines HCV 29T, T24B, Hu 961A and Hu 1703He. Microscopy of HCV29T and Hu 961A cells indicated that this block did not occur in mitosis. The parental cell line T24 and the cell line T24A did not show an accumulation of BrdUrd negative G0/1 cells or BrdUrd positive G2M cells like that occurring in the derived cell line T24B.

The Inhibitor of Histone Deacetylases Sodium Butyrate Enhances the Cytotoxicity of Mitomycin C

“…The obtained results indicated that MMC treatment alone caused S-phase accumulation, consistent with earlier reports on the effect of MMC (22). Treatment with sodium butyrate blocked cells in G 1 and G 2 , causing depletion of Sphase cells, which has also been described (31)(32)(33). In cells treated with both agents, S-phase cells were diminished, whereas the G 2 fraction was increased over 5-fold, compared with those treated with MMC only.…”

Differentiation of BCS‐TC2 human colon adenocarcinoma cells by sodium butyrate: increase in 5′‐nucleotidase activity

“…Morphological changes induced by sodium butyrate depend on the cell line treated; however, the occurrence of flattened and larger cells seems to be a general effect [25,26]. This could be related to the increase in cell protein content that we have also observed in BCS-TC2 cells.…”

HDAC and Hsp90 inhibitors down‐regulate PTTG1/securin but do not induce aneuploidy

“…Also, HDAC inhibition with butyrate has been long associated to numerical chromosome changes (Larsen et al, 1995;Gomez-Vargas and Vig, 2002), although the exact mechanism remains obscure. If repression of PTTG1/securin was accountable in part for the effects observed or if its absence aggravated them was an important question to answer.…”