Ovarian hormone dependence of pre-malignant and malignant mammary gland lesions induced in pre-pubertal rats by 1-methyl-1-nitrosourea

Carcinogenesis
H J ThompsonM Singh

Abstract

The experiments reported in this study were designed to examine the question of whether a mammary epithelial cell's independence from hormonal requirements is established at the time of carcinogenic initiation, or whether the emergence of hormone independence is associated with the process of tumor progression. A newly developed rat model of mammary carcinogenesis was used in which the latency period to lesion detection is very short and in which the frequencies of both pre-malignant and malignant mammary lesions can be quantified. Two experiments were conducted in Sprague-Dawley rats injected with 50 mg MNU/kg body wt at 21 days of age. In the first experiment 47 animals were ovariectomized after the detection of a mammary tumor of palpable size. Forty-six of the 47 tumors assessed, all of which were subsequently classified as mammary gland adenocarcinomas, regressed to <50% of their initial volume within 14 days of bilateral ovariectomy. However, both pre-malignant and malignant mammary gland lesions were observed when animals were killed. In Experiment 2 a total of 60 rats were ovariectomized 7 days after MNU was injected. At 35 days post carcinogen ovariectomized animals had a higher incidence of intraductal proliferations ...Continue Reading

Citations

Aug 3, 2013·Biomedicine & Pharmacotherapy = Biomédecine & Pharmacothérapie·A I Faustino-RochaM Ginja
Mar 5, 2004·Breast Cancer Research and Treatment·Stephen A BoppartKeith W Singletary
Mar 31, 2012·Alcohol and Alcoholism : International Journal of the Medical Council on Alcoholism·Helmut K SeitzCarlo La Vecchia
Sep 21, 2015·Tumour Biology : the Journal of the International Society for Oncodevelopmental Biology and Medicine·Ana I Faustino-RochaMário Ginja
Mar 27, 2018·International Journal of Cancer. Journal International Du Cancer·Wei YueRichard J Santen
Apr 21, 2006·Physics in Medicine and Biology·Adam M ZyskStephen A Boppart
Mar 4, 2000·Laboratory Investigation; a Journal of Technical Methods and Pathology·M SinghH J Thompson
Jun 10, 2009·Journal of Radiation Research·Tatsuhiko ImaokaYoshiya Shimada
Jan 10, 2002·Biochimica Et Biophysica Acta·K Polyak

❮ Previous
Next ❯

Related Concepts

Related Feeds

Carcinoma, Ductal

Ductal carcinoma is a malignant neoplasm involving the ductal systems of any of a number of organs, such as the mammary glands, pancreas, prostate or lacrimal gland. Discover the latest research on ductal carcinoma here.