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PubMed1978

Presence of common surface antigens(s) on endodermal tumors and embryonal tissues of rats, hamsters and mice.

Antiserum against yolk-sac carcinoma of rat was prepared in rabbits. After appropriate absorption in vitro or in vivo this antiserum was examined on different tumors and normal tissues or rat, hamster and mouse. The methods used were indirect immunofluorescence and indirect immunoperoxidase staining and cytotoxicity tests. The immune serum was found to react with the cell membrane of different rat and hamster yolk-sac carcinomas. It reacted also with the cell surface of rat hepatoma cells. By absorption on hyalin and blocking with amniotic fluid it was shown that the antigen was neither a basement membrane component nor alpha-fetoprotein. The antiserum was cytotoxic to yolk-sac carcinoma and hepatoma cells. The immune reaction was limited to the cell membrane, as observed in immunofluorescence and in immunoperoxidase staining. The specificity of the antiserum was proved by cross-absorptions with various tumor lines and by removing its activity with the soluble fraction of yolk-sac carcinoma cells. Non-endodermal rat and hamster tumor lines did not react with the anti-yolk-sac carcinoma immune serum. Most normal adult tissues, including spermatozoa, were negative, but a positive reaction was observed in ovaries and on glandular cells of the uterus. In embryonal tissues this surface antigen(s) was detected in the endoderm of 8-day-old rat embryos 7-day-old mouse embryos and in yolk-sac endoderm of both species. The data indicate that the antigen(s) is associated with endodermal differentiation.

Animals↗
PubMed1980

Lipid droplets in the visceral yolk sac endodermal cells of the postimplantation rat embryo: application of malachite green-glutaraldehyde fixative.

The ultrastructure of the visceral yolk sac (VYS) of the rat embryo at day 9.5 of gestation was examined after fixation with either Karnovsky's glutaraldehyde-paraformaldehyde solution or malachite green-containing glutaraldehyde (MGA) solution. Fixation with MGA retained homogeneously electron-dense droplets in the cytoplasm and the nucleus of endodermal cells, both of which were lost in the specimens prepared by Karnovsky's fixation methods. The cytoplasmic MGA-positive droplets were frequently associated with other cytoplasmic organelles such as rough endoplasmic reticulum, mitochondria and membrane-delineated inclusion bodies, but these cytoplasmic organelles never incorporated MGA-positive materials, whereas Golgi apparatus contained intracisternal MGA-positive droplets. Extracellular MGA-positive droplets were also encountered at the apical surface of endodermal cells and in the intercellular space between endodermal cells and the underlying mesodermal cells. These MGA-positive droplets were considered to be lipid in nature, and their origin in the endodermal cells of VYS is discussed.

Animals↗
PubMed2001

Radial widening of the Casparian strip follows induced radial expansion of endodermal cells.

The Casparian strip, the barrier to apoplastic transport that is located at the endodermis in roots and stems, is formed by individual endodermal cells and is constructed as a highly organized mesh within the primary wall. Since little is known about the mechanism of formation of the strip, we tried to obtain morphological evidence for the existence, prior to suberization and lignification, of some regulatory system at the expected site of the strip. Endodermal cells in etiolated pea stems were induced to expand in the radial direction by piercing the stems through the cortex before formation of the strip. The radial width of the strip increased significantly with the expansion of the radial walls of these endodermal cells. The expansion of the cells occurred before the formation of the strip. However, strips that had already been formed when the stems were pierced did not increase in width despite an induced expansion of the radial walls. These observations suggest that some positional information exists in the radial wall of endodermal cells that defines the future site of formation of the strip and its width.

Biological Transport↗
PubMed1986

Establishment and characterization of a human ovarian endodermal sinus tumor cell line--producing specific type of alpha-fetoprotein subfraction.

A cell line was established from an endodermal sinus tumor of the ovary from a 57-year-old Japanese woman, obtained on July 22, 1982. Histological study of the resected tumor revealed a mixture of reticular, solid and cystic patterns, being consistent with the characteristic feature. The cell line, designated as human Akimoto endodermal sinus tumor (HAEST), was subcultivated over 50 times during 29 months. The cells were spindle or columnar in shape and showed pleomorphic and neoplastic features. The modal chromosome number was stable at diploid range and the marker, large acrocentric, chromosome was identified. The cells were transplanted into the cheek pouch of hamsters and produced an endodermal sinus tumor. alpha-Fetoprotein subfractions in the conditioned media were studied by a modified method of lectin affinity crossed-line immunoelectrophoresis, and we found that the HAEST cells produced concanavalin A nonreactive subfraction, lentil lectin weakly reactive subfraction, phytohemagglutinin-E reactive subfraction and phytohemagglutinin-E nonreactive subfraction, which were predominantly synthesized by the fetal yolk sac, at an early stage of gestation. From these findings, we concluded that the HAEST was indeed an endodermal sinus tumor cell line. This line is expected to have a wide application for various laboratory studies.

Animals↗
PubMed1978

Alpha-fetoprotein, prealbumin, albumin, alpha-1-antitrypsin and transferrin as diagnostic and therapeutic markers for endodermal sinus tumors.

According to Gitlin, alpha-fetoprotein (AFP), albumin, prealbumin, alpha-1-antitrypsin and transferrin are normal products of the human yolk sac. They are expected to reappear in human endodermal sinus tumor (yolk sac tumor). The synthesis of alpha-fetoprotein and other serum proteins by human endodermal sinus tumor was studied in the culture cells and in the tumor tissue transplanted into nude mice. The results gave evidences of synthesis of some of these proteins including alpha-fetoprotein and alpha-1-antitrypsin. Serum concentrations of these proteins were studied in eight children having endodermal sinus tumors. Serum AFP levels were abnormally high in all cases, whereas concentrations of other serum proteins were almost within normal ranges. This might be simply reflected by the fact that pre-albumin, albumin, alpha-1-antitrypsin, and transferrin are already present in large quantities in sera of normal subjects while alpha-fetoprotein is present only in a negligible quantity. Alpha-fetoprotein, as a diagnostic and therapeutic marker of endodermal sinus tumor, showed good correlation to the tumor growth. Serum AFP concentrations declined almost to 0 ng/ml with a half-life of 4 days when surgical removal was complete, whereas serum AFP decreased only to 100-200 ng/ml with radiation and chemotherapy alone.

Adolescent↗
PubMed2003

Intraepithelial carcinoma arising in an endodermal cyst of the posterior fossa.

Endodermal cysts of the central neuraxis are benign, non-neoplastic epithelium-lined cysts arising from endodermal tissue that have been displaced early in fetal life. Intracranial endodermal cysts are rare and usually located in the posterior fossa. The present study involves a 36-year-old man with a typical epithelial cyst in the posterior fossa. Microscopically, the cyst has a simple columnar epithelium with mucus-producing cells, containing an area composed of dysplastic epithelium with evidence of an intraepithelial carcinoma. The atypical cells have a high proliferative fraction demonstrated by Ki-67 immunostain. Based on these findings, the authors view this case as evidence of a malignant transformation of a classic endodermal cyst. The clinicopathologic features and a review of the literature are discussed.

Adult↗
PubMed1982

Clear cell (mesonephroid) tumors of the ovary with characteristics resembling endodermal sinus tumor.

Twenty-five ovarian clear cell tumors and six endodermal sinus tumors were studied by histochemical, immunohistochemical, and ultrastructural methods. The results of the study indicate that some clear cell tumors contain periodic acid Schiff (PAS) positive and diastase resistant hyaline globules, and also basement membrane-like material, which have been previously considered as being observed only in endodermal sinus tumor. In view of this, we would like to emphasize the importance of the presence of the various histological patterns observed in endodermal sinus tumor, in addition to the classical perivascular formations (Schiller-Duval bodies) and the presence of alpha-fetoprotein (AFP), as diagnostic features of endodermal sinus tumor. On the other hand, the presence of glycogen, abundant rough endoplasmic reticulum stacked in parallel rows, and a more uniform histological pattern are indicative of clear cell (mesonephroid) tumor of the ovary.

Adult↗
PubMed1978

The ectomesenchymal-endodermal interaction system of Triturus alpestris in tissue culture: morphological and histochemical characterization of developing neural derivatives.

In the ectomesenchymal-endodermal interaction system (EEIS), a hanging drop culture in which an explant of neural fold from behind the prospective ear region of a Triturus alpestris neurula together with a piece of ventrolateral pharynx endoderm is cultivated, the differentiation of a variety of neural crest-derived cells (nerve cells, pigment cells, cartilage cells, perichondrial cells, Schwann cells) can be followed. While cartilage cells develop only in contact to pharynx endoderm, the differentiation of neural crest-derived neuroblasts, rhombencephalic brain derivatives and epidermis which segregate from the explant of neural fold, does not depend on the presence of pharynx endoderm. The development of neural derivatives was studied with respect to morphology and histochemistry. Outgrowing axons may be observed 2-3 days after the beginning of cultivation. The fibres increase in thickness and length during further development and frequently make contact with other cells. Cytophotometric measurements of Feulgen-stained neural crest cells in the EEIS revealed that 72% of cells had a 2c and 9% a 4c DNA content while 18% were in S phase. Nerve cells had a 2c DNA content and prospective chondroblasts were in S phase. About 60-70% of S phase and 4c cells were observed at the margin of the culture. Neural crest-derived neuroblasts and melanoblasts obviously reacted catecholamine-positive upon formaldehyde-induced fluorescence (FIF), while axons from the brain derivative were catecholamine-negative but acetylcholinesterase (AChE)-positive. Neural crest cells prior to visible differentiation and neural crest-derived neuroblasts were AChE-negative. Catecholamine-positive (= fluorescing) cells can be recognized as either neuro- or melanoblasts prior to displaying phenotypic features. In cultures incubated with 3H-Dopa, freeze-dried, treated with the FIF-procedure, and subjected to autoradiography, only melanoblasts specifically accumulated the label.

Animals↗
PubMed1979

Endodermal sinus tumor of the ovary. Clinicopathologic study of 6 cases.

6 cases of endodermal sinus tumor of the ovary are presented. In 4 patients pure endodermal sinus tumor was found microscopically. 1 patient had endodermal sinus tumor in one ovary and gonadoblastoma in the contralateral one. In another case endodermal sinus tumor was accompanied by an embryonal teratoma. Histologically, the tumor had characteristic features with meshwork of spaces and channels lined by embryonal cells, glomerulus-like structures known as Schiller-Duval bodies, solid aggregates of epithelial cells, hyaline basement membranes and round, PAS-positive small globules found both intra- and extracellulary. In 1 patient the elevated serum alpha-fetoprotein was stated. All patients were treated surgically with adjunctive radiation and/or with chemical agents. None of them were cured. The median duration of survival amounted to 8.5 months. Discussing the value of the more recent approach to diagnostic and therapeutic methods found in the literature, it must be emphasized that the demonstration of elevated serum alpha-fetoprotein in patient with that tumor lend not only further support to its yolk sac origin but also might be useful to monitor response to the therapy applied. It is also of prognostic significance by indicating the presence of residual or recurrent disease, even in its subclinical stage. Combined postoperative irradiation and triple chemotherapy according to the VAC regimen of patients can prevent recurrence and in some cases even may cause permanent remission of the neoplasm.

Adolescent↗
PubMed1998

Endodermal cysts of the posterior fossa. Report of three cases and review of the literature.

The pathogenesis of endodermal cysts of the posterior fossa is still incompletely understood. The authors reviewed three new cases and those reported in the literature to clarify the clinical, pathological, radiological, and surgical characteristics of these lesions. A total of 49 cases were reviewed. Details on demographic profiles, clinical characteristics, histopathological and radiological features, and surgical methods were collected. These cysts have a predominance in male patients (61%) and can occur at any age (birth-77 years). In patients with posterior fossa endodermal cysts there is a bimodal age distribution and headache is the most frequent complaint. On immunohistopathological examination, endodermal cysts were reactive for epithelial membrane antigen and for keratin immunostains whenever the latter were tested. The cysts were reactive for carcinoembryonic antigen in nine of 11 cases. Endodermal cysts were located anterior to the brainstem in 51% of cases and in the fourth ventricle in 21% of cases. They frequently appeared hypodense on computerized tomography scans, and in five cases, the lesion was missed. The cyst's appearance on magnetic resonance imaging is variable. Resection was complete in 19 cases and partial in 11; marsupialization was achieved in two cases. Three recurrences have been reported. Total excision with preservation of neurological function should be the goal. Cranial base approaches are helpful for surgical access in selected examples of these lesions.

Adult↗
PubMed1986

Endodermal sinus tumor of the ovary associated with pregnancy.

The association of endodermal sinus tumor of the ovary with pregnancy is a rare event. Reported is a patient with stage Ic endodermal sinus tumor diagnosed in the 25th week of gestation. She received two cycles of combination chemotherapy consisting of vinblastine, bleomycin, and cisplatin, and delivered a healthy male infant by cesarean section at 32 weeks' gestation. She subsequently completed three more cycles of chemotherapy and remains alive and well. This is the first reported case of a patient with endodermal sinus tumor treated with combination chemotherapy during pregnancy that had a successful outcome for both mother and infant. The literature concerning the association of endodermal sinus tumor and pregnancy and the use of chemotherapy during pregnancy is reviewed.

Adult↗
PubMed1983

Lectin-binding heterogeneity of alphafetoprotein (AFP). An observation in nude mouse xenografts of endodermal sinus tumors and in pediatric surgical patients.

We determined by affinity chromatography on concanavalin A-Sepharose the carbohydrate variant patterns of alphafetoprotein in the sera of 15 infants and children with endodermal sinus tumors (five cases), a neonatal mature teratoma (one case), hepatoblastomas (two cases), pancreatic carcinoma (one case), biliary atresia (four cases), neonatal hepatitis (one case) and neonatal hyperbilirubinemia (one case), in the sera from four normal neonates, and in the sera from two kinds of nude mice bearing human endodermal sinus tumors. Sera from patients with endodermal sinus tumors and pancreatic carcinoma were found to contain a relatively high proportion (48.4 +/- 4.5 and 52.6%) of alphafetoprotein which did not bind to concanavalin A. Sera from nude mice with human endodermal sinus tumors contained AFP, 96.2% of which did not bind to concanavalin A. Sera from patients with other lesions (nine cases) and from normal neonates, whose AFPs are all presumed to be of hepatic origin, contained much less (5.9 +/- 3.6%) of the concanavalin A non-binding AFP variant. These results indicate that human AFP has three distinct patterns of reactivity with concanavalin A and that studies in xenograft models may give important information relating to the glycosylation and secretion process of AFP.

Adolescent↗
PubMed1965

ERYTHROPOIESIS IN THE CHICK EMBRYO: THE ROLE OF ENDODERM.

The endoderm can be separated from the ectomesoderm of the area vasculosa of the early chick embryo. The development of the separated germ layers in organ cultures shows that the endoderm is necessary for the normal formation of blood islands by mesodermal cells. In the absence of endoderm the mesodermal cells undergo erythropoiesis in dispersed groups of cells but do not form endothelium.

Animals↗
PubMed1996

Treatment of endodermal sinus tumor in children using a regimen that lacks bleomycin.

BACKGROUND: The EPO-VAC protocol was initiated to study 1) the efficacy of adding a cisplatin regimen (EPO) to VAC alone (the previous standard of care) and 2) the effect of replacing bleomycin with etoposide in the treatment of pediatric endodermal sinus tumors. METHODS: The eligibility requirements for entry included age <21 years at diagnosis, diagnosis of a primary gonadal or extragonadal tumor (excluding central nervous system tumors and stage I testicular tumors), and histological confirmation of endodermal sinus tumor. Children who met the eligibility criteria were treated with four courses of EPO (etoposide, cisplatin, vincristine) alternating with three courses of VAC (vincristine, dactinomycin, and cyclophosphamide). RESULTS: Eleven children were entered on the protocol. Six patients had extragonadal disease, five patients had ovarian primaries. Seven patients had low-stage tumor (I or II) and four had advanced-stage tumor (III or IV). Three of six evaluable patients attained a complete response at 21 weeks. Three patients with a residual soft tissue mass at restaging underwent further therapy. No patient has relapsed after a median of 51 (range 14-88) months of follow-up. CONCLUSIONS: The results of this protocol suggests that a cisplatin-containing regimen that lacks bleomycin is active in childhood endodermal sinus tumors.

Adolescent↗
PubMed1997

Murine cardiac progenitor cells require visceral embryonic endoderm and primitive streak for terminal differentiation.

Cardiac progenitor cells in avian and amphibian embryos are known to commit to cardiac lineage during gastrulation or early neurulation. These cells require cell interaction with anterior endoderm for their differentiation into cardiomyocytes. However, little is known about cell interaction in mammalian cardiogenesis. We investigated the staging of murine cardiomyocyte commitment and the role of cell interaction in differentiation of cardiac progenitor cells into cardiomyocytes, using cultures of various embryonic regions at 7.25 and 7.5 days post coitum (p.c.), respectively. To evaluate the terminal differentiation of cardiac progenitor cells, we employed three parameters; expression of spontaneous beating, myosin heavy chain (MHC) protein, and cardiac-specific genes (alpha myosin heavy chain, Csx/Nkx2.5 and myosin light chain 2V genes). mRNAs of cardiac-specific genes were detected in 7.25-day p.c. mesoderm by RT-PCR, suggesting that the genetic specification to cardiac lineage initiated in the mesoderm by 7.25 days p.c. The 7.25-day p.c. isolated mesoderm in 48 hr culture, however, failed to differentiate into spontaneous beating cardiomyocytes and exhibited non-organized MHC protein in 19% of these culture. In contrast, all of the 7.5-day p.c. isolated mesoderm differentiated into beating cardiomyocytes even in 24 hr culture. The 7.25-day p.c. mesoderm associated with primitive streak increased MHC protein expression in 93% of these cultures, although they formed beating foci in 3%. The 7.25-day p.c. explants containing both visceral embryonic endoderm and primitive streak succeeded in terminal differentiation into spontaneous beating cardiomyocytes. Our study suggests that cardiac progenitor cells obtain the potency to complete terminal differentiation autonomously at 7.5 days p.c., as a consequence of the multistep induction by cell interactions with both the primitive streak and visceral embryonic endoderm, following the genetic specification to cardiac lineage in the early gastrula stage.

Animals↗
PubMed1996

Unusual aspects of inner cell mass formation, endoderm differentiation, Reichert's membrane development, and amniogenesis in the lesser bulldog bat, Noctilio albiventris.

BACKGROUND AND METHODS: The early embryogenesis of the lesser bulldog bat, Noctilio albiventris (family Noctilionidae), was examined histologically in 59 pregnant females collected from a reproductively synchronized population in Colombia. RESULTS: Early blastocysts of Noctilio are unusual in lacking a typical inner cell mass. Instead, cells inside of the trophoblast are dispersed for a period as a monolayer. A typical inner cell mass (ICM) only forms and becomes properly oriented after the initiation of implantation. Several features of Reichert's membrane in this species are also noteworthy: it develops between the ICM and trophoblast and between the parietal endoderm and trophoblast; it becomes linked to a meshwork of basal laminalike material that extends into the ICM; and it appears to be continuous, or fused, with prominent basal laminae that develop within the cytotrophoblastic villi that radiate throughout the preplacenta. Amniogenesis occurs by cavitation and converts the ICM into a hollow epiblastic vesicle. Gastrulation commences before this vesicle exhibits obvious differentiation into an embryonic shield and amniotic ectoderm. CONCLUSIONS: Because development and proper orientation of a typical ICM in Noctilio occur after the initiation of implantation, these may involve the migration of cells on the interior of the blastocyst and/or an unusual method of early endoderm differentiation. The possibility exists that epiblast, endoderm, and cytotrophoblast may all contribute to the secretion of Reichert's membrane in this bat. Although the early embryogenesis of Noctilio exhibits many similarities to that in phyllostomid bats, substantial differences also exist between these closely related species.

Amnion↗
PubMed2000

Determination of anterior endoderm in Xenopus embryos.

Grafts of anterior endoderm from embryos at stage 28 or later developed according to their fate (i.e., anterior) when transplanted posteriorly. Conversely, grafts from earlier embryos developed according to their new location (i.e., posterior). However, endoderm grafted along with its mesodermal and ectodermal sheath retained its fate regardless of the stage of the donor. We conclude that anterior endoderm in Xenopus embryos is determined at about stage 25 under the influence of mesoderm.

Animals↗
PubMed1988

Teratogenic antibody internalization by rat visceral yolk-sac endoderm in vitro: an ultrastructural colloidal gold tracer study.

Previous work from our laboratory has demonstrated that specific rabbit immunoglobulins G (IgG) against a glycoprotein antigen of rat kidney proximal tubule or a cross-reacting visceral yolk-sac endodermal cell antigen will induce abnormal embryonic development when they are injected into pregnant rats during the period of organogenesis. It has been proposed that these antibodies may induce embryopathy by interfering with functions of the visceral yolk-sac placenta, an important organ providing nutrients to the embryo at this stage of development. In order to gain some insight into the underlying pathogenic mechanism(s) in which specific teratogenic IgG may interfere with visceral yolk-sac functions, we examined the uptake of these teratogenic IgG by the visceral yolk-sac endodermal cells at the electron microscopic level. The results demonstrated that teratogenic rabbit IgG specifically localized on the fuzzy coat of the external apical cell membrane of the visceral yolk-sac endoderm at the intermicrovillous region. Within 5 min, the IgG were rapidly internalized via coated pits and micropinocytic vesicles. Within 30 min, an increasing proportion of gold particles appeared within uncoated vesicles or vacuoles of various sizes; most of the gold particles were in close proximity to the inner membranous lining of the vesicles. Similar findings were observed after 1- or 2-hr incubation. After 24- to 48-hr culture, however, the gold particles appeared to have dissociated from the inner surface of the vesicle membrane.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗