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I J Hollander

Publications and source records attributed to I J Hollander.

6 recordsLinked to original sources
PubMed1992

Adenomyoepithelioma of the breast. A spectrum of biologic behavior.

Adenomyoepitheliomas of the breast have been considered to have limited metastatic potential; axillary node metastasis has been reported, but there has been no report of distant metastasis. We report six cases, including two malignant adenomyoepitheliomas, one of which metastasized to the lung and brain. Patient age ranged from 26 to 63 years (mean 46). Primary tumors were solitary and measured 0.9-3.5 cm (mean 1.7). Five of six tumors presented as palpable masses. Two patients treated by local resection have no evidence of disease at 5 and 18 months' follow-up. Two patients treated by local resection had recurrences, one at 48 the other at 60 months. The fifth patient had a spindle-cell type adenomyoepithelioma diagnosed as malignant because of high mitotic rate and cytologic atypicality of the myoepithelial component. This patient was treated by mastectomy and has no evidence of disease at 18 months. The sixth patient, initially treated by local excision, had six local recurrences over 52 months treated by reexcisions, mastectomies, and radiation. A lung metastasis was resected at 54 months and brain metastases were identified at 60 months with death occurring at 64 months. Both malignant adenomyoepitheliomas had high mitotic rates [11-14/10 high-power fields (HPF)] diffusely throughout the tumors and foci of cytologically malignant cells. The malignant adenomyoepithelioma that metastasized had an infiltrative growth pattern that increased with successive local recurrences. The four other tumors had only isolated areas of mitotic activity (maximum 1-9/10 HPF) and minimal cytologic atypia. Immunohistochemistry performed on five of six cases confirmed dual epithelial/myoepithelial cell populations in all tumors examined, including the metastasis. Electron microscopic examination of the malignant adenomyoepithelioma that metastasized also confirmed dual epithelial/myoepithelial cell populations in a local recurrence and the lung metastasis. We conclude that there is a spectrum of behavior for breast adenomyoepitheliomas with potential for local recurrence and, rarely, distant metastasis.

Adult↗
PubMed1991

Matrix-assisted UV-laser desorption/ionization mass spectrometric analysis of monoclonal antibodies for the determination of carbohydrate, conjugated chelator, and conjugated drug content.

The chemically averaged molecular weights of a variety of native and conjugated monoclonal antibodies, approximately 150,000, were measured by matrix-assisted UV-laser desorption/ionization mass spectrometry. The average mass of the carbohydrate present in a monoclonal antibody was estimated from the difference between the measured mass of the monoclonal antibody and the mass of the protein present in the monoclonal antibody computed from the amino acid translation of the DNA sequence. The loading of chelators and anticancer drugs conjugated to a monoclonal antibody was quantitated from the difference in the measured masses for the conjugated and untreated monoclonal antibody relative to the expected mass change upon conjugation of 1 mol of chelator or drug. The loading results obtained by mass spectrometry were consistent in most cases with measurements obtained by radioactivity trace assay or UV spectrometry. Similar matrix-assisted UV-laser desorption/ionization mass spectrometric studies were also made after reducing untreated and conjugated monoclonal antibodies with dithiothreitol to determine the distribution of carbohydrate and chelator between the light and heavy chains of the molecules. Matrix-assisted UV-laser desorption/ionization mass spectra were used to compute loading values for covalently bound drugs and proteins, while the loading values obtained by use of gel-filtration HPLC and UV spectrometry cannot distinguish between covalently and noncovalently bound drugs and proteins.

Antibodies, Monoclonal↗
PubMed1987

Plasminogen activators and their potential in therapy.

Plasminogen activators (PAs) are proteases that convert plasminogen to plasmin. Plasmin, in turn, is a protease that can lyse a fibrin clot and, therefore, PAs have a primary role in fibrinolysis. Two PAs, urokinase (UK) and streptokinase (SK), have been available for therapeutic use for years. Unfortunately, both can cause systemic fibrinogenolysis and other side effects which have limited their use. Interest has focused on a different enzyme, tissue plasminogen activator (t-PA), which will cause specific clot lysis without systemic problems. The gene for t-PA has been cloned and many biotechnology firms are preparing to produce t-PA for therapeutic use. The properties and potential for therapy of t-PA are reviewed and compared to new forms of other activators, such as pro-urokinase. How the interactions of PAs and inhibitors may affect the use of PAs is also discussed.

Amino Acid Sequence↗
PubMedDate not supplied

Ectopic hormone production by malignant tumors.

Malignant tumours of nonendocrine tissues may produce ectopic hormones. The most likely mechanism is depression of genes which code for hormones. Ectopic hormones are invariably peptides, and each is identical to some peptide product of an endocrine gland. However, the majority of ectopic hormones occur as biologically inactive precursors or subunits and therefore remain occult unless they are specifically sought. When appropriate assays are made for such inactive forms, it is found that ectopic production of hormone-like peptides occurs frequently. Clinical syndromes result only in the relatively rare patients in whom a biologically active form is synthesized in large quantities. Laboratory research in this area improves our understanding of genetic control mechanisms in neoplasia. Ectopic hormones may be of limited use in diagnosis of cancer, especially when multiple markers are measured simultaneously.

Chorionic Gonadotropin↗