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Biomedical subjects

A Borg

Publications and source records attributed to A Borg.

At least 163 records · Page 9Linked to original sources
PubMed1989

Enzyme immunoassay of progesterone receptor in breast cancer biopsy samples. A comparison with the dextran coated charcoal method.

Progesterone receptor was measured in 97 breast cancer biopsy samples with two methods, the multiple point dextran coated charcoal method with Scatchard analysis and enzyme immunoassay. The measurable amount of progesterone receptor was usually higher with enzyme immunoassay (mean increase 30%). When comparing the two techniques quantitatively a high correlation coefficient was obtained (rs=0.88; p less than 0.001). A concordance in terms of progesterone receptor positivity and negativity was obtained in 81 of the samples (84%) when using 10 fmol/ml as the borderline value. If instead the cut-off value used for clinical evaluations at our laboratory (30 fmol PgR/mg protein) was applied, the concordance increased to 94%. The lack of concordance in the remaining samples may be due to difficulties in the interpretation of the Scatchard plots, especially at low receptor concentration levels and to differences in specificity between the two methods in certain samples. One obvious advantage with enzyme immunoassay compared to the dextran coated charcoal method is that significantly less tissue is needed.

Aged↗
PubMed1989

Estrogen receptor enzyme immunoassay in fine-needle aspirates from human breast cancer.

An enzyme immunoassay was compared with a radioligand assay (isoelectric focusing) for estrogen receptor (ER) determination in 100 preoperative fine-needle aspirates from human breast cancer. A strong correlation (rs = 0.85) between the two estimates was found. However, ER estimates by enzyme immunoassay were 6 times higher than with isoelectric focusing, mainly due to an underestimation of ER content with the latter method in highly blood-contaminated or diluted samples. Enzyme immunoassay provided adequate ER measurement even at very high (50%) blood admixture. To study the reliability of ER measurement with enzyme immunoassay in fine-needle aspirates, a comparison was made with estimates in the corresponding surgical biopsies (65 cases). With DNA as reference parameter a significant correlation (rs = 0.68) was obtained. Excluding aspirates with low cellularity (less than 50,000 cells/ml), only one ER negative fine-needle aspirate was found among 47 ER positive surgical biopsies. A few ER positive aspirates corresponded to ER negative surgical biopsies possibly due to tumour heterogeneity or the fact that fine-needle aspiration sometimes may represent a better sampling technique than surgical biopsy.

Biopsy, Needle↗
PubMed1988

Prognostic significance of estrogen and progesterone receptors in stage II breast cancer.

Estrogen (ER) and progesterone receptors (PgR) were evaluated in samples from primary tumors in 539 patients with stage II breast cancer participating in a randomized multicenter controlled clinical trial on adjuvant therapy. At the cut-off points of 10 fmol ER/mg protein and 30 fmol PgR/mg protein, no significant difference in recurrence-free survival (RFS) existed between premenopausal patients with receptor-positive and negative tumors, respectively. After recurrence, premenopausal patients with receptor-positive tumors had a significant longer survival than patients with receptor-negative tumors. In postmenopausal patients not treated with adjuvant tamoxifen, no correlations between RFS and receptor status were found. Patients with ER+ tumors survived longer than patients with ER-tumors. In postmenopausal patients treated with adjuvant tamoxifen, highly significant differences in RFS and in survival were observed when receptor-positive patients were compared with receptor-negative patients. No differences in survival after recurrence were registered among these patients.

Breast Neoplasms↗
PubMed1988

Secretion of glucose in human parotid saliva after carbohydrate intake.

The aims of the present investigation were, first, to follow the secretion of free glucose in parotid saliva in various subjects after a single oral intake of different carbohydrates, and second, to compare the salivary glucose concentration with the concentration in blood. Twenty healthy subjects, three women and 17 men, 20-35 yr of age, participated. They were asked not to eat or drink anything from 10 p.m. the night before the examination. 75 g of carbohydrate (glucose, fructose, or sucrose) dissolved in 300 ml water was ingested the next morning at 8 a.m. One experimental series with glucose was performed in triplicate in 10 of the subjects. Approximately 1.5 ml of citric acid-stimulated parotid saliva was collected before (0 min) and 15, 30, 45, 60, and 120 min after the intake. Salivary concentration of glucose was analyzed enzymatically. Most of the 0-min samples showed a variation in glucose concentration from 5 to 25 mumol/l. After the glucose, fructose, and sucrose intakes, the salivary glucose level increased about 2-4 times, especially in the 30-min samples. A large inter- as well as intra-individual variation was found both in the 0-min samples and in the samples collected after the different intakes. The correlation between the glucose concentration in saliva and blood was higher after than before the carbohydrate intakes.

Adult↗
PubMed1987

Estramustine binding site in human breast cancer biopsy samples. Its relation to estrogen and progesterone receptor levels, age and menopausal status.

Estramustine is a cytotoxic metabolite of estramustine phosphate (Estracyt), which is used in the treatment of prostatic carcinoma. An estramustine binding site (EMBS) at pH 4.8-4.9 was demonstrated in 74 of 306 (24%) breast cancer biopsy samples using isoelectric focusing in polyacrylamide gels. The presence of EMBS was significantly (P less than 0.001) correlated with negative or low estrogen and progesterone receptor values. EMBS positivity was found in 31% of the samples from pre- and perimenopausal patients and in 22% of the samples from postmenopausals. If patients were instead divided into different age groups, EMBS positivity was most frequent in samples from patients between 50 and 59 years of age (42%). With increasing age the percentage of EMBS positivity fell successively. For patients under 50 years, no difference with respect to EMBS positivity between age groups could be demonstrated. The possible value of EMBS determinations in breast cancer tissue specimens for the selection of those patients that will respond to Estracyt therapy should be evaluated.

Adult↗
PubMed1986

A biological marker, strongly associated with early oral contraceptive use, for the selection of a high risk group for premenopausal breast cancer.

In a population-based group of women, consecutively diagnosed, with premenopausal breast cancer there was a significant correlation between tumour size and plasma prolactin (r = 0.30; P less than 0.004). The concentration of estrogen receptor was negatively correlated to tumour size (r = 0.17; P less than 0.09). There were no substantial correlations between tumour size and progesterone receptor, plasma progesterone or estradiol. Adjustments for menstrual cycle day and age did not alter the above findings. The ratio of plasma prolactin and estrogen receptor was significantly greater (P less than 0.037) for the group of the patients that had started using oral contraceptives before the age of 20 as compared with the other patients. Consequently, the tumour size was significantly greater in the group of early users (P less than 0.003). The findings indicate that breast tumours developing in previous early users of oral contraceptives have a low estrogen receptor concentration, while these patients have higher plasma prolactin. The tumour size is greater in early users indicating a poorer prognosis than other women with breast cancer. As early use of oral contraceptives increases breast cancer risk and a high ratio of plasma prolactin and estrogen receptor concentration of the primary tumour characterize early oral contraceptive users the ratio may be a valuable marker for the breast cancer risk.

Adult↗
PubMedDate not supplied

TP53 protein expression analysis by luminometric immunoassay in comparison with gene mutation status and prognostic factors in early stage endometrial cancer.

Mutations in the TP53 tumor suppressor gene have been shown to significantly correlate with poor prognosis in endometrial cancer. In the present study we have evaluated a luminometric immunoassay (LIA) for quantitative estimation of TP53 protein expression in 65 cytosol preparations from endometrial cancer, previously analyzed for mutations in TP53 exons 4-10. LIA showed high (> or = 0.6 ng/mg protein) expression of TP53 protein in all eight tumors with missense mutation, but high protein levels were also detected in 15 tumors with normal TP53 sequence. All four tumors with nonsense or frameshift mutations had low or no TP53 protein expression. LIA was further evaluated in a retrospective study of 201 cytosol samples from endometrial cancer. TP53 overexpression (> = 0.6 ng/mg protein) was observed in 22% of the tumors and correlated with nonendometrioid histology types (P = 0.005), poorly differentiated tumors (P = 0.001), higher FIGO grade (P = 0.001), DNA nondiploidy (P = 0.002), and high S-phase fraction (P = 0.03). After a median follow-up time of 6.8 years (range 0.7-9.9 years), 22 (13%) progressions were observed in the 175 patients with early stage (I-II) disease. TP53 overexpression (P = 0.04), FIGO grade 3 vs. 1 + 2 (P = 0.01), higher age (P = 0.02), and DNA nondiploidy (P < 0.001) showed significant correlation to shorter progression-free survival in these patients. We conclude that TP53 protein analysis by LIA provides an incomplete correlation to mutation status and cannot substitute for mutation analysis in assessment of prognosis in endometrial carcinoma. In comparison to TP53 overexpression and higher FIGO grades, DNA nonploidy status seems to be a better prognostic indicator to define a subset of early stage endometrial cancer patients who may benefit by adjuvant chemotherapy/radiotherapy.

Aged↗
PubMedDate not supplied

Enzyme immuno assay of the estrogen receptor in breast cancer biopsy samples. A comparison with isoelectric focusing.

The estrogen receptor (ER) was measured by isoelectric focusing (IF) and enzyme immuno assay (EIA) in 127 breast cancer samples. When comparing the two techniques quantitatively, a very high correlation coefficient was obtained (rs = 0.98; p less than 0.001). ER recovery increased, however, by a mean factor of 2.5 when EIA was used instead of IF. This increase seemed to be influenced by the ER concentration level, being lower at higher levels. The difference between IF and EIA did not seem to be due to menopausal status. A possible field of application for EIA might be measurement of ER in samples from patients on tamoxifen therapy. In five out of nine such samples, a considerably higher measurable amount of ER was found with EIA than with IF. EIA was also found to be a simpler and less time-consuming method than IF. These advantages should, however, be weighed against the present higher costs.

Biopsy↗
PubMedDate not supplied

Expression and partial characterization of estramustine-binding protein (EMBP) in human breast cancer and malignant melanoma.

The expression of the estramustine/estromustine-binding protein (EMBP) in human mammary cancer and malignant melanoma was examined by immunochemical methods and compared with that in endometrial and ovarian cancers. By RIA measurements, EMBP was detected in 6/17 mammary cancers (range 11.3-2,660 ng/g tissue) and 2/3 malignant melanomas (618 and 1,240 ng/g), whereas endometrial (n = 6) and ovarian (n = 3) cancers exhibited non-detectable levels. In breast cancer, EMBP-expressing tumours were all estrogen receptor-negative, suggesting an inverse correlation between EMBP and hormone responsiveness of the tumour. Biochemical characterization revealed properties of EMBP in mammary tumours and melanomas almost identical to those for EMBP purified from rat ventral prostate: i.e. surface-charge distribution by Mono Q/FPLC ion-exchange chromatography, a molecular weight of 50,000 by gel filtration, and a subunit composition by Western blot analysis under denaturing conditions. Finally, the EMBP immunoreactivity was confined to the cytoplasm of malignant cells in breast cancer and melanoma sections by immunohistochemical examination. This is the first study that demonstrates EMBP in mammary cancer and malignant melanoma. Our findings suggest that a mechanism for selective uptake of cytotoxic estramustine and estromustine is prevailing in these malignancies and that monitoring of EMBP in biopsy samples will be of value in defining patients who may benefit from Estracyt treatment.

Breast Neoplasms↗