Embryonal tumors

Embryonic tumors (T4) that arise in the fetus or in young children frequently show a mixed population of differentiated and undifferentiated cells. This evidence suggests that the tumors may result from developmental disturbances during organogenesis that cause arrest of an early stage in the normal differentiation process to adult tissue. Enhanced expression of the N-myc oncogene has been... 

Mork SJ, Rubinstein LJ. Ependymoblastoma A reappraisal of a rare embryonal tumor. Cancer. 1985 55 1536-1542. 

Embryonal carcinoma cell lines have also been established in culture from transplantable teratocarcinomas. The embryonal carcinoma (EC) stem cells present in the tumors actually differentiated, and give rise to a variety of different types of embiyonic and adult cells. When these EC cells are cultured, they still possess the... 

Di Ciistofano, A., Pesce, B., Cordon-Cardo, C., Pandolfi, P.P., 1998, Pten is essential for embryonic development and tumor suppression. Nat. Genet., 19 348-355. 

Ho, A., Wakeham, A, Itie, A., Khoo, W., Fukumoto, M., and Mak, T.W., 1998, High cancer susceptibility and embryonic lethality associated with mutation of the PTEN tumor suppressor gene in mice. Curr. Biol. S 1169-1178. 

Some new materials perspective for advanced biomedical technologies, especially carbon nanoparticles like fullerenes, are potentially mutagenic, carcinogenic and immunogenic [16,65], Therefore, standard tests of the morphological transformation of Syrian hamster embryonic cells in cultures on these materials (described in detail by [68,69]) can be performed. Immune activation of bone and vascular cells on the materials can be estimated by increased concentration of immunoglobulin and selectin adhesion molecules (ICAM-1, VCAM-1, ELAM-1), which bind cells of the immune system [15,16,18,19,23], as well as by the production of cytokines, such as tumor necrosis factor alpha or interleukins beta [55],... 

Fetner has also demonstrated chromatid breaks in a human tissue-culture cell line exposed to ozone at 8 ppm for 5 min. Other tissue-culture studies include that of Sachsenmaier et who noted tetraploidy and other chromosomal abnormalities in embryonic chick fibroblasts exposed to ozone and a decrease in transplantability of mouse ascites tumor cells. In addition, Pace et demonstrated an interference by ozone with mitotic activity in two tissue-culture cell lines. More recently, Booher et al. reported that lung cells exposed in culture to ozone concentrations as low as 0.3 ppm demonstrated an inhibition in growth that was proportional to the ozone concentration. 

Gastrointestinal, pancreas, biliary, lung, transitional cell, sweat glands, mucosal squamous cell, mucinous carcinomas of female GU tract, medullary carcinoma of thyroid Breast, squamous cell, endometrioid, Brenner tumor Renal cell, hepatocellular, prostate, follicular thyroid, adrenal cortical, serous carcinomas of female GU tract, embryonal, yolk sac, mesothelioma... 

Gregory, R.I. et al. (2002) Inhibition of histone deacetylases alters allelic chromatin conformation at the imprinted U2afl-rsl locus in mouse embryonic stem cells. J. Biol. Chem. 277, 11728-11734. Thomas, G., Lange, H.W., and Hempel, K. (1975) Kinetics of histone methylation in vivo and its relation to the cell cycle in Ehrlich ascites tumor cells. Eur. J. Biochem. 51, 609-615. 

BRGl/BRM BRGl/BRM Likely to be similar to human SNF5/INI1 component is required for embryonic development and tumor... 

Klochendler-Yeivin, A., Fiette, L., Barra, J., Muchardt, C., Babinet, C., and Yaniv, M. (2000) The murine SNF5/INI1 chromatin remodeling factor is essential for embryonic development and tumor suppression. EMBO Rep. 1, 500-506. 

The growth of tissue (or, more precisely, the number of cells) is actually regulated by apoptosis. In addition, apoptosis allows the elimination of unwanted or superfluous cells—e.g., during embryonic development or in the immune system. The contraction of the uterus after birth is also based on apoptosis. Diseased cells are also eliminated by apoptosis—e.g., tumor cells, virus-infected cells, and cells with irreparably damaged DNA. An everyday example of this is the peeling of the skin after sunburn. 

The body s cells are normally subject to strict social control. They only divide until they come into contact with neighboring cells cell division then ceases due to contact inhibition. Exceptions to this rule include embryonic cells, cells of the intestinal epithelium (where the cells are constantly being replaced), cells in the bone marrow (where formation of blood cells takes place), and tumor cells. Uncontrolled cell proliferation is an important indicator of the presence of a tumor. While normal cells in cell culture only divide 20-60 times, tumor cells are potentially immortal and are not subject to contact inhibition. 

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