Gabriel Seman

Studies on the presence of particles resembling RNA virus particles in human breast tumors, pleural effusions, their tissue cultures, and milk

Ultrastructural studies have been carried out on biopsies of 84 breast cancers, 13 metastatic lymph nodes, 3 fibroadenomas, and on cells from 33 pleural effusions from breast cancer patients. Breast tumor tissues of 157 patients and pleural effusion cells of 36 patients have been put in tissue culture. Growth has been obtained of cells derived from 47% of the breast tumor biopsies and from 90% of the pleural effusions. However, no cell line could be established. Milk specimens of 4 women with breast cancer and of 17 apparently healthy women also have been examined for the presence of virus particles. Particles resembling murine type B and/or type C virus particles and small virus‐like particles have been observed in a number of specimens. Particles resembling type B and/or type C virus particles have been found in 34 of the 100 breast tumor, metastatic lymph node, and fibroadenoma biopsies. They also have been observed in 2 of 33 specimens of pleural effusions, in 4 of 72 tissue culture specimens, and in 4 of 21 milk specimens. Small virus‐like particles have been observed in 29 of the 100 biopsy specimens and in 3 of 38 tissue cultures derived from breast tumors. They also have been shown in 4 of 21 milk specimens. The relationship of these virus‐like particles to the origin of human breast neoplasia remains to be clarified.

Immunofluorescence studies on sera of patients with breast carcinoma

Indirect immunofluorescence tests were carried out on sera of 42 patients with breast carcinoma, 4 with fibrocystic disease, and 45 blood bank donors. Thirty‐one of the 46 sera showed positive reaction which consisted of faint nucleolar and strong cytoplasmic fluorescence in cells of tissue cultures derived from either 1 breast carcinoma, 1 case of fibrocystic disease, or 2 osteosarcomas. Sera of 3 breast cancer patients reacted with breast cancer cells only; sera of 6 breast cancer patients and of 1 with fibrocystic disease reacted with fibrocystic disease cells only; sera of 7 breast cancer patients reacted with breast cancer and fibrocystic disease cells; and sera of 3 breast cancer patients reacted with cells of breast cancer, fibrocystic disease, and osteosarcoma. Sera of 2 breast cancer patients reacted with cells of breast cancer and osteosarcoma, and sera of 5 breast cancer patients and of 2 with fibrocystic disease reacted with cells of fibrocystic disease and osteosarcoma. Sera of a small number of patients with osteosarcoma reacted with fibrocystic disease, and osteosarcoma cells and sera of these patients reacted also with breast cancer cells. None of the sera tested reacted with cells of the following cultures: giant cell tumor, rhabdomyosarcoma, Levine‐3 cell line, HEK‐1‐HRLV (human embryo kidney culture producing Rauscher leukemia virus), normal human embryo, and human adult skin. All sera from blood bank donors were negative with cells of all cultures tested. Absorption experiments with some of the positive sera indicate that the fluorescence reaction may be due to a tumor antigen.

Electron microscope observation of viruslike particles in comedocarcinoma of the human breast

We have previously reported the observation of viruslike particles resembling mouse mammary tumor and mouse leukemia virus particles in a number of breast tumor biopsy specimens. Viruslike particles of two different types have been observed by electron microscope examination of a breast tumor specimen of a patient with comedocarcinoma and Hashimotos disease. The particles have all been found in endoplasmic cisternae of epithelial tumor cells. Viruslike particles of one type, represented by 80 millimicrons in size particles arranged in chainlike formations, showed some general features of the hamster type H virus particles; however, no distinct spokes originating from the nucleoid could be seen as described in type H particles. Viruslike particles of the other type resembled type C virus particles, but were larger (200 millimicrons) in size and, unlike type C particles, were found only in the cisternae of the endoplasmic reticulum. No viruslike particles have been found in biopsy specimens of two other patients with comedocarcinoma. The morphological characteristics of these viruslike particles are discussed in view of recent findings by others of virus particles in tissue cultures derived from breast and other types of human tumors.

Virus-Like Particles in a Case of Human Prostate Carcinoma

Two morphologically different types of intracisternal virus-like particles were observed electron microscopically in a biopsy specimen of human prostate cancer. Particles of one type were 150-200 nm in diameter and contained either an electron-dense core or two concentric inner layers. Particles of the other type were smaller, 80-100 nm in diameter, and appeared mostly in filamentous or chainlike formation. Both types of particles and budding were observed in endoplasmic cavities of epithelial tumor cells. The particles had ultrastructural characteristics that suggested a viral nature but were different from the known type B, type C, or type H (hamster type R) virus particles. This was the first election microscopic observation in prostate cancer of virus-like particles similar to those previously reported in a case of human breast carcinoma.