Sucrase‐isomaltase: A marker of foetal and malignant epithelial cells of the human colon

Abstract

The presence of sucrase-isomaltase (SI), a glycoprotein hydrolase normally restricted to the brush border membrane of the enterocytes of the small intestine, was investigated in tumours which developed in nude mice inoculated with six human colon carcinoma cell lines (HT-29, Caco-2, HRT-18, HCT-8R, SW-480, and CO-115). Foetal and normal adult human small intestines and colons were used as controls. SI was studied by (1) immunofluorescence with rabbit antibodies raised against purified human small intestine SI; (2) polyacrylamide gel electrophoresis and immunoblotting; and (3) determination of the enzyme activity. SI was antigenically present, and enzymatically active, in all the tumours derived from Caco-2 and HT-29 cells. The presence of the enzyme was associated with that of typical brush borders at transmission electron microscopy examination. SI was absent from the tumours developed with the other four cell lines, as well as from the normal adult colon mucosa. SI was also present and active in the colons of mid-gestation foetuses, ranging in ages between 20 and 28 weeks; it was absent from the colons of late-gestation foetuses. The presence of SI in tumours derived from two cell lines suggests that this enzyme is a marker, so far unsuspected, of certain human colon cancers, and that the differentiation pattern of these particular cancers closely resembles that of the foetal colon.

Maturation of Sucrase-Isomaltase Complex in Human Fetal Small and Large Intestine during Gestation

“…They are in good accordance with previous reported values for fetal intestine (5,8,15). For the 1 5 , 18-, and 24-wk samples, the results were obtained from homogenate of the whole intestinal mucosa, and we observed a progressive rise in activity between 15 and 24 wk; at 24 wk the activity was near adults values.…”

“…Sucrase-isomaltase from a blood group 0 human small intestine was purified as previously described (10,15). Briefly brushborders were digested with papain; the papain supernatant was applied on sequential chromatographic columns including anion exchange chromatography, gel filtration, and Sephadex G 200 chromatography.…”

“…This enzyme also is expressed at a lower level in human fetal colonic mucosa between 10 and 30 wk. The activity disappears at term and is not expressed in adult colon (5,15). We studied the spontaneous maturation of human fetal small intestinal and colonic sucrase-isomaltase complex throughout gestation, and compared the fetal and adult enzymes.…”

Recovery of Exfoliated Cells From the Gastrointestinal Tract of Premature Infants: A New Tool to Perform “Noninvasive Biopsies?”

“…Colon cancer cells (Caco-2 cell line purchased from European Collection of Animal Cell Culture, UK; ECACC#860120) with an enterocytic differentiation (12) were derived from a human colon cancer and were grown in Dulbecco's modified Eagle medium (DMEM) supplemented with 10% fetal calf serum, 2 mM L-glutamine, and penicillin-streptomycin (Invitrogen, Cergy Pontoise, France). These cells were used as control in parallel experiments to check for cellular capture and detection of specific glycoprotein (11) by the kit, Western blot analysis, and RT-PCR.…”

Two-step stimulation of intestinal Ca2+absorption during lactation by long-term prolactin exposure and suckling-induced prolactin surge

“…Duodenum was used in this study because it is the efficient site for both transcellular and paracellular Ca 2ϩ transport (18). In some experiments, human colorectal adenocarcinoma Caco-2 monolayer, a standard model for Ca 2ϩ absorption study, was used since it can be genetically manipulated and has functional properties similar to the small intestinal cells (6,44,45).…”