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At least 775 records · Page 43Linked to original sources
PubMed2001

Alterations of gene expression in endoderm differentiation of F9 teratocarcinoma cells.

During the endoderm differentiation of F9 mouse embryonal carcinoma cells, as induced by sodium butyrate (NaBu) or retinoic acid (RA), gene expressions of alkaline phosphatase (ALPase), pyruvate kinase (PKase) and 5' ribonucleotide phosphohydrolase (5'-Nase) were examined. The specific activity of ALPase was found to increase by 3.5-fold after 48 hr treatment with NaBu. In contrast, specific activity of PKase were decreased by 63%. Northern blot analysis revealed that the elevation of ALPase activity resulted from an increase in the level of liver/bone/kidney (L/B/K)-type ALPase mRNA and that the decrease of PKase activity was dependent on a reduction in the level of M(2)-PKase mRNA. Interestingly, when NaBu was removed from the culture medium, the levels of these mRNAs reverted to their original levels after 16 h. During these processes, the specific activity of 5'-Nase and the level of its mRNA remained unchanged. In contrast, when F9 cells were treated with RA, only the level of L/B/K-type ALPase mRNA increased. Lastly, we examined the issue of whether an increase in the level of ALPase mRNA is dependent on the transcriptional activation of the mouse L/B/K-type ALPase gene. Transient transfection assays using luciferase reporter constructs showed that the promoter activity increased as the result of treatment with RA but not with NaBu.

5'-Nucleotidase↗
PubMed1994

Endo16, a large multidomain protein found on the surface and ECM of endodermal cells during sea urchin gastrulation, binds calcium.

Endo16 encodes a developmentally regulated protein restricted to cells participating in the formation of the archenteron during sea urchin gastrulation and to the stomach of the pluteus. The 4680-nt coding region of the Endo16 gene has been sequenced from overlapping cDNAs. Sequence analysis revealed that Endo16 is a large multidomain protein starting with a putative signal sequence at its amino terminus which is followed by a cysteine-rich region, two potential heparin-binding regions, an acidic domain of 5 clustered repeats, an RGD cell binding motif, and a group of 12 additional acidic repeats. Immunolocalization by confocal and electron microscopy demonstrate that the Endo16 protein is in the extracellular matrix and associated with the surface of endodermal cells in the mid and hindgut of the archenteron. The two distinct acidic repeat regions are similar to known calcium-binding sequences. A recombinant Endo16 protein containing both putative calcium-binding repeat regions has been shown to bind radioactive calcium. Tryptic digests of gastrula stage protein extracts in the presence and the absence of calcium have established that calcium stabilizes Endo16 protein against proteolytic degradation.

Amino Acid Sequence↗
PubMed2000

Elongation of axolotl tailbud embryos requires GPI-linked proteins and organizer-induced, active, ventral trunk endoderm cell rearrangements.

Application of phosphatidylinositol-specific phospholipase C to early tailbud stage axolotl embryos reveals that a specific subset of morphogenetic movements requires glycosylphosphatidylinositol (GPI)-linked cell-surface proteins. These include pronephric duct extension, "gill bulge" formation, and embryonic elongation along the anteroposterior axis. The work of Kitchin (1949, J. Exp. Zool. 112, 393-416) led to the conclusion that extension of the notochord provided the motive force driving anteroposterior stretching in axolotl embryos, elongation of other tissues being a passive response. We therefore conjectured that axial mesoderm cells might display the GPI-linked proteins required for elongation of the embryo. However, we show here that removal of most of the neural plate and axial and paraxial mesoderm prior to neural tube closure does not prevent elongation of ventrolateral tissues. Tissue-extirpation and tissue-marking experiments indicate that elongation of the ventral trunk occurs via active, directed tissue rearrangements within the endoderm, directed by signals emanating from the blastopore region. Extension of both dorsal and ventral tissues requires GPI-linked proteins. We conclude that elongation of axolotl embryos requires active cell rearrangements within ventral as well as axial tissues. The fact that both types of elongation are prevented by removal of GPI-linked proteins implies that they share a common molecular mechanism.

Ambystoma↗
PubMed1996

Impairment of mobility in endodermal cells by FAK deficiency.

Focal adhesion kinase (FAK) is a novel nonreceptor protein tyrosine kinase that localizes in focal adhesions. It is expressed in a variety of cell types, and we reported earlier that is deficiency causes a decrease of mobility in mesodermal cells with enhanced formation of focal adhesions. With embryoid bodies generated from embryonic stem cells, we also observed a decrease of mobility in FAK-deficient endodermal cells with enhanced focal adhesion formation.

Animals↗
PubMed2001

Retinoid X receptor alpha and retinoic acid receptor gamma mediate expression of genes encoding tight-junction proteins and barrier function in F9 cells during visceral endodermal differentiation.

Retinoids are critical for differentiation of columnar epithelial cells and for preventing metaplasia of these cells into stratified squamous epithelial cells, in which tight junctions (TJs) are essentially absent. This implies that retinoids might play important roles in regulating the structures and functions of TJs of columnar epithelium. F9 murine embryonal carcinoma cells differentiate into epithelial cells resembling visceral endoderm bearing TJs, when grown in suspension as aggregates in the presence of retinoic acid (RA). We show that RA induces the TJ structure and expression of several TJ-associated molecules, such as ZO-1, occludin, claudin-6, and claudin-7, as well as a barrier function in the genetically engineered cell line F9:rtTA:Cre-ER(T) L32T2, which allows sophisticated genetic manipulations simply by addition of ligands (H. Chiba et al., 2000, Exp. Cell Res. 260, 334-339). Interestingly, our data indicate that a barrier for small substances is generated after that for large ones during de novo formation of TJs. We also compared the RA-induced expression of TJ components and barrier function in RXRalpha(-/-)-RARgamma(-/-) F9 cells with those in wild-type cells and show that the retinoid signals for transduction of these events are mediated by specific RXR-RAR pairs.

Animals↗
PubMed1999

ZNF74, a gene deleted in DiGeorge syndrome, is expressed in human neural crest-derived tissues and foregut endoderm epithelia.

DiGeorge syndrome (DGS) is a developmental disorder associated with large hemizygous deletions on chromosome 22q11.2. ZNF74 zinc finger gene is a candidate from the commonly deleted region. To address the potential involvement of ZNF74 in DGS, its human developmental expression pattern has been assessed. In situ hybridization on Carnegie Stage 18 embryos revealed that ZNF74 expression is limited to specific neural crest-derived tissues and neuroepithelium of the spinal cord as well as to foregut endoderm epithelia (esophagus and respiratory tract). Interestingly, ZNF74 expression was detected in the wall of the pulmonary artery and aorta and in the aortic valve, which are populated by neural crest-derived cells. This finding is significant, considering that DGS is believed to result from defective neural crest contributions and that outflow tract and aorticopulmonary septation defects are typical features of the DGS phenotype. Thus, the restricted expression of ZNF74 in structures affected in DGS suggests a role for this putative regulator of gene expression in aspects of the DGS phenotype.

Aorta↗
PubMed1994

Endodermal sinus tumor arising from a dysgenetic gonad in a 46,XX female combined with müllerian agenesis.

The occurrence of neoplastic transformation in a dysgenetic gonad of a female with 46,XX karyotype is very rare. Moreover, to our knowledge, a case of endodermal sinus tumor arising from that setting combined with Müllerian agenesis has not been reported. This case suggests the possibility of development of cancer in a dysgenetic ovary of a female even with 46,XX or Müllerian agenesis.

Adult↗
PubMed1995

Conus-cauda syndrome as a presenting symptom of endodermal sinus tumor of the ovary.

We report on a case of a 46-year-old woman with a conus-cauda syndrome due to an endodermal sinus tumor of the right ovary with multiple metastases in the spine and pelvic bone. Before removing the tumor surgically, combination chemotherapy was given to treat the metastases, which threatened to compromise the spinal cord.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

Endodermal sinus tumor and embryonal carcinoma of the ovary in a 53-year-old woman.

BACKGROUND: Germ cell tumors, the most common ovarian malignancies in females under the age of 21, are rare in older women. We report an unusual case of a mixed embryonal carcinoma and endodermal sinus germ cell tumor in a perimenopausal patient and review the differential diagnosis and management of these malignancies with respect to age. CASE: A 53-year-old woman complaining of irregular menses and pelvic pain was found to have a large pelvic mass and a positive pregnancy test. Subsequent investigation revealed a large left adnexal mass, and an elevated beta-HCG and alpha-AFP. At laparotomy, a mixed germ cell tumor was found. The patient was treated with multiagent chemotherapy and currently is without evidence of disease. CONCLUSION: Although rare, the diagnosis of germ cell tumor should be considered in older women presenting with a large pelvic mass. The treatment and prognosis is similar regardless of age, except that reproductive-sparing surgery is not a priority in the older patient.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

An endodermal sinus tumor diagnosed in pregnancy: case report and review of the literature.

OBJECTIVE: The use of chemotherapeutic drugs in pregnancy is a rare occurrence. Experience and results need to be shared. METHOD: At 23 weeks gestational age, a patient was diagnosed with an endodermal sinus tumor of the ovary. She received one course of postoperative bleomycin, cisplatin, and etoposide. One week later, the patient was investigated for increasing abdominal pain and the fetus was noted to have ventriculomegaly. RESULTS: The baby was delivered, and the patient was surgically staged and completed chemotherapy. Although the patient is alive and well 16 months after delivery, the infant has developed significant ventriculomegaly with cerebral atrophy. CONCLUSION: The etiology of this infant's significant cerebral atrophy is not clear. Tumor-specific, perioperative, or drug-related events must be considered.

Adult↗
PubMed1999

Primary endodermal sinus tumor of the omentum.

Endodermal sinus tumor (EST) is a rare neoplasm which usually arises in the testis or ovary. But extragonadal EST is well recognized and may arise in a wide array of sites such as the mediastinum, vagina, and brain. We report a case of primary EST of the omentum and to our knowledge it is the first case of omental EST in the literature. A 45-year-old woman with a history of abdominal distension was treated with total abdominal hysterectomy with bilateral salpingo-oophorectomy and infracolic omentectomy, followed by four cycles of BEP (bleomycin, etoposide, cisplatin) combination chemotherapy. Microscopically, the tumor exhibited typical patterns of EST and stained for alpha-fetoprotein and cytokeratin. She has remained free of disease for 10 months of follow-up. According to previous studies, debulking surgery and BEP chemotherapy were used as primary therapy with good results. The subject of extragonadal EST is reviewed, and the possible histogenesis of this tumor at such a rare site is discussed.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1982

Distribution of a galactose-specific lectin in endoderm cells from early chick embryos.

Cells from the endoderm of the area opaca of gastrulating chick embryos were maintained in stationary cultures, stained with antibodies against the endogenous beta-D-galactoside-binding lectin and examined by immunofluorescence. In the majority of cells fluorescence was present as an irregular circular web in the central cytoplasm. In cells that appeared to be migrating increased fluorescence was observed in the peripheral cytoplasm and retraction fibers. In regions where a portion of the cell was detaching from the substratum high fluorescence was observed in the extracellular "footprints" deposited by the cell.

Animals↗
PubMed1976

Localisation of proteins in coated micropinocytotic vesicles during transport across rabbit yolk sac endoderm.

Rabbit yolk sac splanchnopleur exposed in utero to IgG-HRP and IgG-ferritin conjugates, rabbit and bovine anti-HRP antibodies, free HRP, ferritin and human IgG, was examined ultrastructurally in an attempt to determine whether or not coated micropinocytotic vesicles are involved in selectively transporting immunoglobulins across yolk sac endodermal cells. Human, rabbit and bovine IgG-HRP conjugates, rabbit anti-HRP antibodies, free HRP and human IgG, all become localised in coated micropinocytotic vesicles. Differences were observed in that only human IgG and rabbit anti-HRP antibodies could be located in the intercellular space and bovine IgG-HRP conjugate could not be detected in coated micropinocytotic vesicles in confluence with the lateral and basal plasmalemma. Bovine anti-HRP anti-bodies, IgG-ferritin conjugates, and free ferritin, could not be observed in coated micropinocytotic vesicles. All proteins were detected in macropinocytotic vesicles, and dense bodies resembling phagolysosomes. Results are discussed in the light of a proposal that selection occurs at the cell surface during formation of coated micropinocytotic vesicles and is not linked to intracellular proteolysis.

Animals↗
PubMed1981

An integrated experimental study of endoderm formation in avian embryos.

The formation of the endoderm during primitive streak stages in avian embryos was studied by combining several of the following techniques for each embryo. These included microsurgery, time-lapse filming, use of chick-quail chimaeras, tritiated thymidine autoradiography and a novel technique for identifying the morphology of the cells after small pieces of tissue from known areas had been maintained in culture for 24 h. Using these techniques we have confirmed that the ventral layer of the early chick embryo receives contributions from both the marginal and the central regions of the area pellucida. The former seems to consist of yolky cells derived from the germ wall, whilst the latter consists of smaller, less yolky cells derived from the more dorsal layers of the embryo. The movement of the lower layer anteriorly during these stages appears to be dependent upon mechanical constraints imposed upon it by the expanding tissue in more caudal regions. The extent of each of the two contributions to the lower layer was determined as a function of stage and presence or absence of a lower layer, and the findings are discussed in the light of the existing literature.

Animals↗
PubMed1986

Effects of leupeptin on endocytosis and membrane recycling in rat visceral yolk-sac endoderm.

The effect of exposure to leupeptin (25 micrograms/ml for 24 h) on the endocytotic activity and the membrane flow of apical cell membranes was studied in endodermal cells of cultured rat visceral yolk sacs by applying a double-labelling method using concanavalin-A ferritin (Con-A Fer) and horseradish peroxidase (HRP). Control and leupeptin-treated yolk sacs were labelled with Con-A Fer at 4 degrees C and then incubated with HRP for 5, 15 or 60 min at 37 degrees C. In controls, HRP reaction product was detected after 5 min in many of the apical vacuoles as well as a few lysosomes; after 15 min, reaction product was observed in all apical vacuoles and in lysosomes of various sizes. These HRP-positive structures usually contained a variable amount of membrane-bound Fer. After 60 min, all apical vacuoles and almost all lysosomes exhibited HRP reactions, but only some of these structures contained Fer particles. At this time, many apical canaliculi (which are involved in membrane recycling) exhibited positive HRP reactions and sometimes also contained Fer particles. In leupeptin-treated cells, HRP reaction product and variable amounts of membrane-bound Fer particles were found in apical vacuoles after 5 min; after 15 min, both labels were also observed in some small lysosomes, and after 60 min, they were found in all apical vacuoles as well as some small and middle-sized lysosomes. Significantly fewer labelled apical vacuoles, lysosomes and apical canaliculi were present after leupeptin treatment than in controls at corresponding times. At all times examined, the giant lysosomes found in leupeptin-treated cells did not exhibit any labeling.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Comparative enzyme histochemical study on the visceral yolk sac endoderm in the rat in vivo and in vitro.

Histochemical study of the visceral yolk-sac endoderm of the rat was performed in vitro (whole-embryo culture for 24, 48 and 72 h explanted at 9.5 days of gestation) and in vivo (10.5, 11.5 and 12.5 days of gestation) in order to compare the distribution and activity of various enzymes involved in the digestion and energy metabolism in both systems. It was shown that, both in vitro and in vivo gamma-glytamyltransferase and dipeptidylpeptidase IV are demonstrable in the apical cell membranes (membrane-bound hydrolases), while acid phosphatase, dipeptidylpeptidases I, II and acid beta-galactosidase are concentrated in the supranuclear vacuoles (lysosomal hydrolases), and cytoplasmic lactate dehydrogenase and mitochondrial enzymes (succinate dehydrogenase, NAD-dependent isocitrate dehydrogenase, cytochrom oxidase) are localized in the whole cytoplasm and mainly in the apical cytoplasm, respectively, of the visceral yolk-sac epithelium. In vivo, the activity of all enzymes increased until 12.5 days, but in vitro, this activity increased only until 48 h after the start of culture (corresponding to 11.5 days in vivo). Comparison of the yolk sacs at 10.5 and 11.5 days in vivo with those after 24 and 48 h in vitro showed that the activities of all the investigated enzymes were almost identical. Yolk sacs which were cultured for 72 h showed lower activities of lysosomal and mitochondrial enzymes than those at 12.5 days in vivo. It is concluded that the digestive function and energy metabolism of the visceral yolk-sac epithelium are almost identical in vitro and in vivo at 10.5 and 11.5 days.

Animals↗
PubMed1988

Peptide immunoreactivity in developing entero-endocrine cells in endodermal grafts.

Presumptive endoderm was excised from 19-h chick or quail embryos and grafted, together with a fragment of notochord from a 48-h host chick embryo. After 14 days the graft showed differentiation towards several digestive and respiratory tract structures. Entero-endocrine cells were demonstrated in these structures. Peptide immunoreactivity in these structures was similar to some extent to the peptide spectrum in corresponding regions during normal development, though the number of demonstrable peptides per region under the conditions of grafting appeared to be higher than in control conditions.

Animals↗
PubMed1986

Pulmonary adenocarcinoma of fetal type: alternating differentiation argues in favour of a common endodermal stem cell.

Pulmonary adenocarcinoma exhibit different cell types that ultrastructurally, appear to be related to the different epithelial cell types occurring in the terminal lung lobule. The present paper describes the light-microscopical, ultrastructural and immunohistochemical features of a newly defined type of pulmonary adenocarcinoma that resembles an early stage of lung differentiation. The alternating epithelial differentiation within this tumour speaks in favour of a common endodermal stem cell for the different types of epithelial cells within the lung, including endocrine cells. The relationship of this tumour to pulmonary blastoma is discussed.

Adenocarcinoma↗