methylthiouracil and Adenocarcinoma

Topics: Adenocarcinoma; Adenoma; Animals; Methylthiouracil; Microscopy, Electron, Scanning; Neoplasms, Experimental; Neoplasms, Radiation-Induced; Rats; Thyroid Gland; Thyroid Neoplasms

Irradiation of the neck region of 10 days old Wistar rats with 300 rads X-rays and their subsequent treatment with MTU leads to the development of thyroid tumors. The ultrastructure of the thyroid tumors induced was studied by transmission (TEM) and scanning electron microscopy (SEM). In follicular carcinomas, cylindrical or high columnar cells with abundant microvilli, well-developed ergastoplasmic reticulum and a hypertrophied Golgi complex predominate. The cytoplasm of the tumor cells of papillary carcinomas was composed of large pleomorphic cisternae, irregular in shape mitochondria, dense bodies, phagolysosomes and lamellar or multivesicular structures. Scanning electron microscopy revealed in the control animals a regular pattern of thyroid follicles tied to each other by tissue bridges and covered by set of blood and lymph vessels. The relief of the follicular carcinomas was irregular indicating follicles different in size and shape. The internal surface of the neoplastic follicles was also irregular as result of deep invaginations and intrafollicular cell growth. The apical region of the normal and neoplastic thyroid follicular cells was covered with abundant microvilli protruding into the colloid.

Topics: Adenocarcinoma; Animals; Carcinoma, Papillary; Male; Methylthiouracil; Microscopy, Electron; Microscopy, Electron, Scanning; Neoplasms, Experimental; Neoplasms, Radiation-Induced; Rats; Thyroid Neoplasms

Nuclear DNA content was measured in 3 normal, 9 hyperplastic and 16 neoplastic rat thyroid glands. Thyroid hyperplasia and tumor growth were induced after treatment of the animals with X-rays and methylthiouracil. In the control animals only diploid thyroid epithelial cells were observed. At the stages of diffuse and nodular thyroid hyperplasia, the total DNA content per nucleus indicated for a diploid chromosome number and only a few cells were hyperdiploid. In the thyroid adenomas and carcinomas a scattering of the diploid region and an increase in the number of hyperdiploid cells was found. Among the various types of thyroid tumors neither difference in the number of hyperdiploid cells, nor typical pattern of distribution of these cells in the histogram was found. The increased number of hyperdiploid cells in the hyperplastic and neoplastic thyroids suggest an increase in the proportion of the cells entering the cell cycle and does not indicate for appearance of a neoplastic stemline.

Topics: Adenocarcinoma; Adenoma; Animals; Carcinoma, Papillary; Cell Nucleus; Cystadenoma; DNA; DNA, Neoplasm; Epithelium; Hyperplasia; Male; Methylthiouracil; Neoplasms, Experimental; Neoplasms, Radiation-Induced; Rats; Thyroid Gland; Thyroid Neoplasms

Topics: Adenocarcinoma; Administration, Oral; Animals; Carcinoma; Carcinoma, Papillary; Injections, Intravenous; Methylthiouracil; Neoplasms, Experimental; Nitrosourea Compounds; Rats; Thyroid Neoplasms; Time Factors

Topics: Adenocarcinoma; Adenoma; Animals; Female; Golgi Apparatus; Hyperplasia; Methylthiouracil; Microscopy, Electron; Neoplasms, Experimental; Rats; Thyroid Neoplasms

Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Carcinoma 256, Walker; Dactinomycin; Fluorouracil; Melphalan; Mercaptopurine; Methylthiouracil; Mice; Mice, Inbred Strains; Neoplasm Transplantation; Neoplasms, Experimental; Nitrogen Mustard Compounds; Rats; Sarcoma, Experimental; Time Factors

Topics: Adenocarcinoma; Animals; DNA; Female; Mammary Glands, Animal; Mammary Neoplasms, Experimental; Methylthiouracil; Mice; Mice, Inbred Strains; Thyroid Hormones

Topics: Adenocarcinoma; Animals; Basophils; Female; Hypothyroidism; Liver Neoplasms; Mammary Neoplasms, Experimental; Methylthiouracil; Neoplasms, Experimental; Ovarian Neoplasms; Pituitary Gland; Rats; Thyroid Neoplasms; Thyroidectomy

Topics: Adenocarcinoma; Adenoma; Animals; Cell Nucleolus; Cell Nucleus; Golgi Apparatus; Hyperplasia; Methods; Methylthiouracil; Microscopy, Electron; Mitochondria; Neoplasms, Experimental; Organoids; Rats; Ribosomes; Thyroid Diseases; Thyroid Gland; Thyroid Neoplasms; Time Factors

Topics: Adenocarcinoma; Carcinogens; Kidney Diseases, Cystic; Kidney Neoplasms; Methylthiouracil; Neoplasms; Neoplasms, Experimental; Pathology; Rats; Research