Biomaterial Database

Morphological maturation of tumor cells induced by ethylnitrosourea (ENU) in rat brains. II. On the tumors by administration of ENU in the mid-gestational stage. 1985

T Yoshino

In order to clarify the relationship between cellular characteristics of rat brain tumors and the administration time of chemical carcinogens, the incidence and morphology of microtumors in the offspring of five pregnant Sprague-Dawley rats injected with ethylnitrosourea (ENU) intraperitoneally on the 11th day of gestation (Group I) were compared with those of six pregnant rats injected with ENU on the 18th day of gestation (Group II). Twenty-four microtumors and 6 macrotumors were obtained in Group I and 58 microtumors and 5 macrotumors in Group II. Histologically, the macrotumors of Group I showed a poorly differentiated pattern which corresponded to primitive spongioblastomas in comparison with those of Group II which resembled human mature oligodendrogliomas, astrocytomas or mixed gliomas. The constituent cells of the microtumors of both groups were immature and were morphologically similar to each other. Immunohistochemically, the cells of microtumors of both groups were negative for Leu 7 and glial fibrillary acidic protein. Microtumors in Group I showed more infiltrative proliferation than those in Group II and had indistinct borders. The 3H-thymidine labeling index of the constituent cells of Group I was significantly higher than that of Group II (p less than 0.001). This study revealed that the constituent cells of microtumors of Group I, in spite of being morphologically similar with those of Group II, possess a greater growth potency than the latter. This difference in growth potency is responsible for the difference in the histological maturity of the macrotumors in each group. The difference in morphological maturation of enlarged gliomas induced by ENU appears to depend on the imperceptible difference of the target cell maturation at the initiation of oncogenesis.

UI	MeSH Term	Description	Entries
D009837	Oligodendroglioma	A relatively slow-growing glioma that is derived from oligodendrocytes and tends to occur in the cerebral hemispheres, thalamus, or lateral ventricle. They may present at any age, but are most frequent in the third to fifth decades, with an earlier incidence peak in the first decade. Histologically, these tumors are encapsulated, relatively avascular, and tend to form cysts and microcalcifications. Neoplastic cells tend to have small round nuclei surrounded by unstained nuclei. The tumors may vary from well-differentiated to highly anaplastic forms. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, p2052; Adams et al., Principles of Neurology, 6th ed, p655)	Oligodendroblastoma,Anaplastic Oligodendroglioma,Mixed Oligodendroglioma-Astrocytoma,Mixed Oligodendroglioma-Ependymoma,Oligodendroglioma, Adult,Oligodendroglioma, Childhood,Oligodendroglioma, Well-Differentiated,Well-Differentiated Oligodendroglioma,Adult Oligodendroglioma,Adult Oligodendrogliomas,Anaplastic Oligodendrogliomas,Childhood Oligodendroglioma,Childhood Oligodendrogliomas,Mixed Oligodendroglioma Astrocytoma,Mixed Oligodendroglioma Ependymoma,Mixed Oligodendroglioma-Astrocytomas,Mixed Oligodendroglioma-Ependymomas,Oligodendroblastomas,Oligodendroglioma, Anaplastic,Oligodendroglioma, Well Differentiated,Oligodendroglioma-Astrocytoma, Mixed,Oligodendroglioma-Astrocytomas, Mixed,Oligodendroglioma-Ependymoma, Mixed,Oligodendroglioma-Ependymomas, Mixed,Oligodendrogliomas,Oligodendrogliomas, Adult,Oligodendrogliomas, Anaplastic,Oligodendrogliomas, Childhood,Oligodendrogliomas, Well-Differentiated,Well Differentiated Oligodendroglioma,Well-Differentiated Oligodendrogliomas
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011297	Prenatal Exposure Delayed Effects	The consequences of exposing the FETUS in utero to certain factors, such as NUTRITION PHYSIOLOGICAL PHENOMENA; PHYSIOLOGICAL STRESS; DRUGS; RADIATION; and other physical or chemical factors. These consequences are observed later in the offspring after BIRTH.	Delayed Effects, Prenatal Exposure,Late Effects, Prenatal Exposure
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D001932	Brain Neoplasms	Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.	Brain Cancer,Brain Metastases,Brain Tumors,Cancer of Brain,Malignant Primary Brain Tumors,Neoplasms, Intracranial,Benign Neoplasms, Brain,Brain Neoplasm, Primary,Brain Neoplasms, Benign,Brain Neoplasms, Malignant,Brain Neoplasms, Malignant, Primary,Brain Neoplasms, Primary Malignant,Brain Tumor, Primary,Brain Tumor, Recurrent,Cancer of the Brain,Intracranial Neoplasms,Malignant Neoplasms, Brain,Malignant Primary Brain Neoplasms,Neoplasms, Brain,Neoplasms, Brain, Benign,Neoplasms, Brain, Malignant,Neoplasms, Brain, Primary,Primary Brain Neoplasms,Primary Malignant Brain Neoplasms,Primary Malignant Brain Tumors,Benign Brain Neoplasm,Benign Brain Neoplasms,Benign Neoplasm, Brain,Brain Benign Neoplasm,Brain Benign Neoplasms,Brain Cancers,Brain Malignant Neoplasm,Brain Malignant Neoplasms,Brain Metastase,Brain Neoplasm,Brain Neoplasm, Benign,Brain Neoplasm, Malignant,Brain Neoplasms, Primary,Brain Tumor,Brain Tumors, Recurrent,Cancer, Brain,Intracranial Neoplasm,Malignant Brain Neoplasm,Malignant Brain Neoplasms,Malignant Neoplasm, Brain,Neoplasm, Brain,Neoplasm, Intracranial,Primary Brain Neoplasm,Primary Brain Tumor,Primary Brain Tumors,Recurrent Brain Tumor,Recurrent Brain Tumors,Tumor, Brain
D002454	Cell Differentiation	Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.	Differentiation, Cell,Cell Differentiations,Differentiations, Cell
D004261	DNA Replication	The process by which a DNA molecule is duplicated.	Autonomous Replication,Replication, Autonomous,Autonomous Replications,DNA Replications,Replication, DNA,Replications, Autonomous,Replications, DNA
D005038	Ethylnitrosourea	A nitrosourea compound with alkylating, carcinogenic, and mutagenic properties.	Nitrosoethylurea,N-Ethyl-N-nitrosourea,N Ethyl N nitrosourea
D005260	Female		Females
D005865	Gestational Age	The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated from the onset of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization. It is also estimated to begin from fertilization, estrus, coitus, or artificial insemination.	Embryologic Age,Fetal Maturity, Chronologic,Chronologic Fetal Maturity,Fetal Age,Maturity, Chronologic Fetal,Age, Embryologic,Age, Fetal,Age, Gestational,Ages, Embryologic,Ages, Fetal,Ages, Gestational,Embryologic Ages,Fetal Ages,Gestational Ages