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Sulphation of lithocholic acid in the colon-carcinoma cell line CaCo-2.

ABSTRACT: High levels of bile acids in the colon may correlate with an increased risk of colon cancer, but the underlying mechanisms are not known. Proteoglycan structures have been shown to change when human colon cells differentiate in vitro. The expression of [(35)S]sulphated molecules was used as a phenotypic marker to study the effects of bile acids on the human-colon-carcinoma cell line CaCo-2. [(35)S]sulphated compounds were isolated from the medium of cell fractions of cells metabolically labelled with [(35)S]sulphate in the absence and presence of cholic acid, deoxycholic acid, chenodeoxycholic acid and lithocholic acid (LA). Labelled molecules were analysed by gel chromatography, HPLC and SDS/PAGE in combination with chemical and enzymic methods. The expression of (35)S-labelled proteoglycans was not affected by any of the bile acids tested. However, the level of sulphated metabolites increased 7-18-fold in different experiments during a 22 h labelling period in the presence of an LA concentration of 10 microg/ml (26.6 nmol/ml) compared with controls. Further analyses showed that this was due, at least in part, to the sulphation of LA itself. This sulphation of LA was a rapid process followed by secretion back to the medium. Brefeldin A did not reduce the sulphation of LA, indicating that this conversion takes place in the cytosol, rather than in the Golgi apparatus of the CaCo-2 cells. LA in colon may be sulphated efficiently by the colonocytes to reduce the toxic effects of this particular bile acid. Sulphation may possibly be an important protective mechanism in the colon.

SUBMITTER: Halvorsen B

PROVIDER: S-EPMC1220583 | biostudies-other | 1999 Nov

REPOSITORIES: biostudies-other

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Lithocholic acid and sulphated lithocholic acid differ in the ability to promote matrix metalloproteinase secretion in the human colon cancer cell line CaCo-2.

Project description:The human colon carcinoma cell line CaCo-2 has the ability to sulphate the secondary bile acid lithocholic acid (LA), whereas other primary or secondary bile acids were not sulphated [Halvorsen, Kase, Prydz, Gharagozlian, Andresen and Kolset (1999) Biochem. J. 343, 533--539]. To study the biological implications of this modification, CaCo-2 cells were incubated with either LA or sulphated lithocholic acid (3-sulpholithocholic acid, SLA), and in some experiments with taurine-conjugated lithocholic acid. Increased secretion of matrix metalloproteinases (MMPs) correlates with transformation of colon epithelial cells. When CaCo-2 cells were incubated with LA, the secretion of MMP-2 was found to increase approx. 60% when analysed by gelatin zymography, and 80% when analysed by Western blotting. SLA, in contrast, did not affect the level of MMP-2 secretion, and after zymography the level of enzyme activity was 78% of control values after 18 h incubation. The secretion of MMPs is linked to increased cellular invasion and, in tumours, to increased capacity for metastasis. The ability of CaCo-2 cells to invade in a chamber assay was stimulated after exposure to LA, whereas SLA-treated cells did not differ from control cells. LA therefore seems to induce a more invasive CaCo-2 cell phenotype, as judged by the two parameters tested, whereas the sulphated counterpart, SLA, did not have these effects. Sulphation of LA in the colon may be an important mechanism to decrease the potential LA has to promote a malignant epithelial phenotype.

| S-EPMC1221136 | biostudies-other

Identification of transport pathways for citric acid cycle intermediates in the human colon carcinoma cell line, Caco-2.

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| S-EPMC2323910 | biostudies-literature

HCMV-Mediated Interference of Bortezomib-Induced Apoptosis in Colon Carcinoma Cell Line Caco-2.

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| S-EPMC7827311 | biostudies-literature

Expression and protein kinase C-dependent regulation of peptide/H+ co-transport system in the Caco-2 human colon carcinoma cell line.

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| S-EPMC1138049 | biostudies-other

Acrylamide Decreases Cell Viability, and Provides Oxidative Stress, DNA Damage, and Apoptosis in Human Colon Adenocarcinoma Cell Line Caco-2.

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| S-EPMC7024287 | biostudies-literature

Purines induce lipofuscin formation in a colon carcinoma cell line.

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| S-EPMC1137090 | biostudies-other

Synthesis, Structure-Activity Relationship, and Mechanistic Investigation of Lithocholic Acid Amphiphiles for Colon Cancer Therapy.

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| S-EPMC4322782 | biostudies-literature

Effects of some anti-diabetic herbal extracts on the insulin-degrading enzyme in human colon cancer Caco-2 cell line.

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| S-EPMC9516401 | biostudies-literature

Time-dependent activity and expression of glutathione S-transferases in the human colon adenocarcinoma cell line Caco-2.

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| S-EPMC1133624 | biostudies-other

Human bocavirus 1 infection of CACO-2 cell line cultures.

Project description:Human bocavirus 1 (HBoV1) is a parvovirus associated with pneumonia in infants. It has been detected in different tissues, including colorectal tumors. In this study, we investigated whether Caco-2 cell line, derived from human colon cancer, can be utilized as a model for HBoV1 replication. We demonstrate HBoV1 replication in Caco-2 cultures supplemented with DEAE-dextran after inoculation with respiratory material from infected patients presenting with acute respiratory infection. A viral cycle of rapid development is displayed. However, in spite of HBoV1 DNA 4-fold increment in the supernatants and monolayers by day 1, evidencing that the system allows the virus genome replication after the entry occurred, infectious progeny particles were not produced. These results are consistent with an infection that is limited to a single growth cycle, which can be associated to mutations in the NS1 and VP1/VP2 regions of HBoV1 genome. Further research will contribute to fully elucidate these observations.

| S-EPMC7172243 | biostudies-literature

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