0000000000329769
AUTHOR
Clemens A. Schmitt
Expression and regulation by interferon-γ of the membrane-bound complement regulators CD46 (MCP), CD55 (DAF) and CD59 in gastrointestinal tumours
The membrane-bound complement inhibitors CD46 (membrane cofactor protein), CD55 (decay-accelerating factor) and CD59 (protectin) protect tumour cells against lysis by activated complement. In this study, a total of 14 (3 gastric, 3 colonic and 8 pancreatic) gastrointestinal tumour cell lines were examined for the expression of CD46, CD55 and CD59 with respect to the regulatory efficacy of interferon-gamma (IFN-gamma). The effects of IFN-gamma on mRNA and protein expression levels of CD46, CD55 and CD59 were evaluated by Northern blot hybridisation, RT-PCR, flow cytometry and immunostaining. In unstimulated cell lines, CD46 and CD59 transcripts were expressed at comparable levels, whereas th…
Elevated serum E-selectin in patients with liver metastases of colorectal cancer
E-selectin, an endothelial cell adhesion molecule, mediates the initial step of leucocyte adhesion to activated vascular endothelium. The soluble isoform of E-selectin promotes angiogenesis in rat cornea. In the present study, we investigated whether leucocyte adhesion and angiogenesis are also involved in tumour progression and metastasis of colorectal cancer. Therefore, we determined the level of circulating soluble E-selectin in serum samples of 38 patients with colorectal cancer; 20 patients with non-metastatic and 18 patients with metastatic disease. Median levels of soluble E-selectin were found to be significantly higher in metastatic tumour disease (88.7 ng/ml, range 25-203 ng/ml) t…
?(1,3)Fucosyltransferase expression in E-selectin-mediated binding of gastrointestinal tumor cells
E-selectin recognizes the oncofetal antigen sialyl-Lewis X, which is highly expressed in adenocarcinoma. Five α(1,3)fucosyltransferases (FT) have been cloned that confer cell-surface expression of sialyl-Lewis X on transfected cells. We show here that 12/18 gastrointestinal-tumor cell lines bind specifically to immobilized E-selectin and that in sialyl-Lewis-X-positive cells binding is inhibited with a monoclonal antibody against sialyl-Lewis X. Using RT-PCR, we determined the expression of the α(1,3)fucosyltransferases III, IV, V, VI and VII in gastrointestinal tumor cells. Transcripts of FT IV and FT VII are abundantly expressed in all tested cells. Therefore no single fucosyltransferase …
Synthetic lethal metabolic targeting of cellular senescence in cancer therapy.
Activated oncogenes and anticancer chemotherapy induce cellular senescence, a terminal growth arrest of viable cells characterized by S-phase entry-blocking histone 3 lysine 9 trimethylation (H3K9me3). Although therapy-induced senescence (TIS) improves long-term outcomes, potentially harmful properties of senescent tumour cells make their quantitative elimination a therapeutic priority. Here we use the Eµ-myc transgenic mouse lymphoma model in which TIS depends on the H3K9 histone methyltransferase Suv39h1 to show the mechanism and therapeutic exploitation of senescence-related metabolic reprogramming in vitro and in vivo. After senescence-inducing chemotherapy, TIS-competent lymphomas but …
Detection of the DCC gene product in normal and malignant colorectal tissues and its relation to a codon 201 mutation.
Protein expression of the putative tumour-suppressor gene DCC on chromosome 18q was evaluated in a panel of 16 matched colorectal cancer and normal colonic tissue samples together with DCC mRNA expression and allelic deletions (loss of heterozygosity, LOH). Determined by a polymerase chain reaction (PCR)-LOH assay, 12 of the 16 (75%) cases were informative with LOH occurring in 2 of the 12 cases. For DCC mRNA, transcripts could be detected in all analysed normal tissues (eight out of eight) by RT-PCR, whereas 6 of the 15 tumours were negative. DCC protein expression, investigated by immunohistochemistry using the monoclonal antibody 15041 A directed against the intracellular domain, was hom…