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S Gamulin

Publications and source records attributed to S Gamulin.

33 records · Page 2Linked to original sources

Relationship of cytoplasmic and nuclear estrogen receptors and progesterone receptors in human breast cancer.

The qualitative and quantitative relationships between cytoplasmic estrogen receptors (ERC), total nuclear estrogen receptors (ERN), and cytoplasmic progesterone receptors (PGR) in 74 primary and 23 metastatic human breast cancer tissues were studied. A positive correlation between the age of th patients and the receptor concentration was found only for ERC. Although ERN and PGR were more frequent in tumors with a higher level of ERC, there was no significant correlation between concentrations of either ERN or PGR and ERC. However, PGR were more frequent in ERN-positive than in ERN-negative tumors, irrespective of the presence of ERC. There was also a highly significant correlation between PGR and ERN concentrations. These findings support the assumption that induction of PGR by estrogen in human breast cancer is mediated by a mechanism involving nuclear receptors. Therefore, the ERN assay might increase the validity of steroid receptor determination for prediction of hormonal sensitivity of human breast cancer.

Adult↗

Effects of cadmium on polyribosome sedimentation pattern in mouse liver.

Cadmium injected to mice provokes an acute disaggregation of hepatic polyribosomes. The effect appears within 15 min, it is maximal after 1 h and then gradually disappears. The reaggregation of polyribosomes takes place 6--12 h after injection. The disaggregation of polyribosomes is linear with log doses in a range of 7.25--20 mumol/kg CdCl2. Cycloheximide pretreatment prevents the disaggregation of polyribosomes in the livers of cadmium-treated mice.

Animals↗

Effect of cadmium on polyribosome structure and function in mouse liver.

Cadmium chloride injected to mice (20 micronmoles/kg) provokes in the livers a degradation of polyribosomes and diminishes their protein synthetic ability measured in vitro. CdCl2 added in a final concentrations between 30 and 100 micron to the protein synthetic cell-free system derived from livers of control mice inhibits its activity.

Animals↗

Ribosome function in livers of porphyric mice.

1. A porphyrinogenic drug, 3,5-diethoxycarbonyl-1,4-dihydrocollidine, caused a decrease in the proportion of single ("run off") ribosomes, and an increase in the number of polyribosomes, in the livers of treated animals. 2. No change could be detected in the distribution of amino acid incorporation among hepatic polyribosomes.

Amino Acids↗

The distribution of ribosomes between different functional states in livers of fed and starved mice.

1. To investigate the role of ribosome function in regulating protein synthesis, the activity, distribution and functional states of ribosomal particles were investigated in livers of mice fed ad libitum or starved overnight. 2. The distribution of protein-synthesizing activity between polyribosomes of different sizes was analysed after incorporation of radioactive leucine, and the quantitative distribution of ribosomes as native subunits, monomers and polyribosomes was analysed after incorporation of orotic acid. Precursors labelled with (3)H or (14)C were given separately to fed and starved mice, so that livers from the two groups of animals were processed together. 3. The former experiments showed that starvation has little effect on the distribution of protein-synthesizing activity across polyribosome sedimentation patterns, though the latter experiments showed that the proportion of ribosomes existing as monomers increased from 9.5% to 15.2%, whereas the proportion existing as polyribosomes decreased from 81.4% to 75.6%. Starvation had a negligible effect on the proportion of native subunits, which accounted for 9.1% and 9.2% of the ribosomes in fed and starved mice respectively. 4. The monomeric ribosome fraction was isolated and subjected to ionic conditions which selectively dissociate single ribosomes. Starvation increased the proportion of monomers that dissociated from 59% to 72%, so the monomers that accumulate in livers of starved animals are single ribosomes and not monoribosomes resulting from degradation of polyribosomes. 5. The fate of newly formed ribosomal particles was studied by measuring the specific radioactivity of native subunits, monomers and polyribosomes at different times after injection of radioactively labelled orotic acid. Starvation did not appear to affect equilibration between newly formed particles and polyribosomes, and the radioactivity of polyribosomes in both groups of mice reached about 90% of that in native subunits after 4h. The radioactive labelling of monomers proceeded at a slower rate, especially after starvation. At 4h, the radioactivity of monomers was 64% and 55% that of native subunits in fed and starved mice respectively.

Journal Article↗

Mutual predictive value of c-erbB-2 overexpression and various prognostic factors in ductal invasive breast carcinoma.

AIMS AND BACKGROUND: Breast carcinoma is a heterogeneous disease, the prognosis of which correlates with various prognostic factors. The aim of this study was to assess the prognostic significance of c-erbB-2 overexpression in breast carcinoma patients in association with other known prognostic factors. METHODS & STUDY DESIGN: The relationship between immunohistochemical expression of the c-erbB-2 oncoprotein and various established prognostic factors such as tumor size, axillary node status, estrogen and progesterone receptor status, DNA ploidy, proliferation index, cathepsin D expression and histological grade in invasive ductal breast carcinoma is presented in this study. RESULTS: Of the 93 ductal invasive carcinomas 22 (23.7%) were grade I, 51 (54.8%) grade II, and 20 (21.5%) grade III, and the majority (78: 83.9%) were 2-5 cm in diameter. Tumor metastases were identified in one or more lymph nodes in 55 (59.1%) patients, the remaining 38 (40.9%) patients being lymph node negative. According to the DNA histograms 40 (43.0%) tumors were aneuploid and 53 (57.0%) were diploid, and the majority of tumors had more than 4% of cells in the S phase of the cell cycle (83.9%). Expression of c-erbB-2 as shown by immunohistochemical intense membrane staining was present in 49 (52.7%) tumors. Cathepsin D-positive cytoplasmic granular staining and cathepsin D-positive stromal macrophages were found in 60 (64.5%) and 72 (77.4%) tumors, respectively. Univariate analysis showed that overall survival correlated significantly with axillary lymph node involvement and with estrogen and progesterone receptor status for each of the receptors separately and for their coexpression, and only marginally with c-erbB-2 overexpression. In mulitivariate analysis only axillary lymph node metastases and coexpression of estrogen and progesterone receptors were found to be independent and significant prognostic factors. CONCLUSIONS: When patients were stratified according to c-erbB-2 expression it was shown that those with c-erbB-2 overexpression and grade II tumors, tumor size greater than 2 cm, high content of aneuploid cells and cathepsin D-positive stromal macrophages had a shorter long-term survival than c-erbB-2 negative patients.

Adult↗