Butyrate-Induced Cell Death and Differentiation Are Associated with Distinct Patterns of ROS in HT29-Derived Human Colon Cancer Cells

Abstract

To investigate the role of reactive oxygen species (ROS) induced by butyrate in tumor cells, we compared HT29R, an HT29-derived human colon cancer cell line refractory to butyrate-induced cell differentiation but highly sensitive to cell death, with the differentiation-positive HT29-12 and HT29-21 cell lines (exhibiting low sensitivity to butyrate-induced cell death), with respect to levels of butyrate-induced free radicals (FRs), ROS, and H(2)O(2). Dose-dependent increase of FRs (as determined by electron spin resonance spectroscopy) and ROS (dichlorofluorescein assay) was induced in HT29R, but not in HT29-12 and HT29-21 cells, where, in contrast to HT29R, a dose-dependent increase of H(2)O(2) release (phenol red assay) was induced by butyrate. The mode of butyrate-induced cell death in HT29R cells was of a mixed type with necrosis predominating, which, however, switched to apoptosis as the major type of cell death in the presence of the drugs 1,5-dihydroxyisoquinoline, resveratrol, or cyclosporine A. The results suggest that FRs and ROS induced by butyrate in HT29R cells are products of cell death, while H(2)O(2) induced in HT29-12 and HT29-21 cells is functionally related to cell differentiation.

Fatty acids as potential adjunctive colorectal chemotherapeutic agents

“…Contrasting results were described for the cell death resistant cell lines HT29-12 and HT29-21, with minimal induction of cell death and generation of low levels of reactive oxygen species and increased production of H 2 O 2 . 73 The difference in cell death rate was reportedly the result of glucose uptake, with some cell lines utilizing butyrate instead of glucose. 43 Modulation of the redox system thus has powerful implications for the rate of cell proliferation and apoptosis, potentially providing an effective tool as a CRC adjunctive therapy.…”

Protein kinase Cγ in colon cancer cells: Expression, Thr514 phosphorylation and sensitivity to butyrate-mediated upregulation as related to the degree of differentiation

“…We examined the phosphorylation of the potential PKCγ targets MARCKS and Elk-1 in HT29 cells as affected by butyrate, and could not detect any difference in the level of phosphorylations, in spite of the butyrate-mediated upregulation of PKCγ (data not shown). In previous studies [24] we investigated butyrate-induced differentiation, cell death and reactive oxygen species in HT29 and derived cell lines. Since the cell lines differed considerably in the above-mentioned butyrate-induced effects, the PKCγ expression and its sensitivity to butyrate, which is quite similar in these cell lines cannot be related to the above-mentioned phenomena.…”

“…HT29-12 and HT29-21 were isolated based on their methotrexate-resistant phenotype [22], HT29cl.19a cells as resistant to 5 mM butyrate [23]. HT29R cells are resistant to butyrate-induced differentiation [24]. All the cell lines employed in this study namely, HT29, HT29-12, HT29-21, HT29R, Caco2, IEC-18, HCT116, Lovo, SW480 and DLD-1 cells were kindly provided as validated cell lines [25] by Dr. Albert Amberger, Tyrolean Cancer Research Institute, Innsbruck, Austria.…”

“…Especially, HT29R and Lovo cells appeared to be highly sensitive to butyrate. Butyrate-induced cell death in HT29R and the other HT29-derived cell lines was investigated in a previous study [24].…”

Raw Chinese Yam (Dioscorea opposita) Promotes Cecal Fermentation and Reduces Plasma Non-HDL Cholesterol Concentration in Rats

“…SCFA production in the large intestine contributes to inhibited hepatic cholesterol synthesis ( 10 ) and could suppress the proliferation of colon cancer cells ( 11 ). These effects are assumed to prevent the development of coronary heart disease and colon cancer.…”