The short-chain fatty acid butyrate is a substrate of breast cancer resistance protein.

Abstract

Colorectal cancer is one of the most common cancers worldwide. Butyrate (BT) plays a key role in colonic epithelium homeostasis. The aim of this work was to investigate the possibility of BT being transported by P-glycoprotein (MDR1), multidrug resistance proteins (MRPs), or breast cancer resistance protein (BCRP). Uptake and efflux of (14)C-BT and (3)H-folic acid were measured in Caco-2, IEC-6, and MDA-MB-231 cell lines. mRNA expression of BCRP was detected by RT-PCR. Cell viability, proliferation, and differentiation were quantified with the lactate dehydrogenase, sulforhodamine B, and alkaline phosphatase activity assays, respectively. In both IEC-6 cells and Caco-2 cells, no evidence was found for the involvement of either MDR1 or MRPs in (14)C-BT efflux from the cells. In contrast, several lines of evidence support the conclusion that BT is a substrate of both rat and human BCRP. Indeed, BCRP inhibitors reduced (14)C-BT efflux in IEC-6 cells, both BT and BCRP inhibitors significantly decreased the efflux of the known BCRP substrate (3)H-folic acid in IEC-6 cells, and BCRP inhibitors reduced (14)C-BT efflux in the BCRP-expressing MDA-MB-231 cell line. In IEC-6 cells, combination of BT with a BCRP inhibitor significantly potentiated the effect of BT on cell proliferation. The results of this study, showing for the first time that BT is a BCRP substrate, are very important in the context of the high levels of BCRP expression in the human colon and the anticarcinogenic and anti-inflammatory role of BT at that level. So, interaction of BT with BCRP and with other BCRP substrates/inhibitors is clearly of major importance.

• Authors: Pedro Gonçalves, Inês Gregório, Fátima Martel
• Journal: American journal of physiology. Cell physiology (Am J Physiol Cell Physiol) Vol. 301 Issue 5 Pg. C984-94 (Nov 2011) ISSN: 1522-1563 [Electronic] United States
• PMID: 21775706 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• ABCB1 protein, human
• ABCG2 protein, human
• ATP Binding Cassette Transporter, Subfamily B
• ATP Binding Cassette Transporter, Subfamily B, Member 1
• ATP Binding Cassette Transporter, Subfamily G, Member 2
• ATP-Binding Cassette Transporters
• Abcg2 protein, rat
• Neoplasm Proteins

Topics

• ATP Binding Cassette Transporter, Subfamily B
• ATP Binding Cassette Transporter, Subfamily B, Member 1 (metabolism)
• ATP Binding Cassette Transporter, Subfamily G, Member 2
• ATP-Binding Cassette Transporters (metabolism)
• Animals
• Breast Neoplasms (metabolism)
• Caco-2 Cells
• Cell Differentiation
• Cell Line, Tumor
• Cell Proliferation
• Cell Survival
• Colorectal Neoplasms (metabolism)
• Female
• Humans
• Neoplasm Proteins (metabolism)
• Rats