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J A Holt

Publications and source records attributed to J A Holt.

At least 55 records · Page 3Linked to original sources
PubMed1991

Antigen CA 19-9: presence in mucosa of nondiseased müllerian duct derivatives and marker for differentiation in their carcinomas.

CA 19-9, a side branch of the Lewis blood group system, is a sialylated Lewis A antigen that is highly expressed by many adenocarcinomas of the digestive tract. The müllerian duct-derived mucosa of the uterus and fallopian tubes also synthesizes Lewis blood group antigens. To test whether the expression of CA 19-9 is enhanced in carcinomas of müllerian duct origin, we performed immunohistochemical staining for CA 19-9 in normal tissues from 33 women and in adenocarcinomas from 88 patients. In the normal uterine cervix, CA 19-9 was expressed in the cytoplasm of scattered glandular cells in 26 of 29 specimens. It was observed in the apical regions of mucosal cells in six of 26 normal endometrial samples and two of 13 normal fallopian tube specimens. These results are consistent with the presence of antigen CA 19-9 on a secretory product of the nondiseased mucosa of the müllerian duct. In adenocarcinomas of the endocervix, endometrium, and fallopian tubes, CA 19-9 was found in seven of 11, 57 of 71, and five of six samples, respectively. Progressive loss of differentiation was accompanied by disruption of subcellular localization of CA 19-9 and its secretion toward the glandular lumina. In well-differentiated regions of tumors, the antigen was detected mainly at the luminal surface of cancerous glands, whereas the staining was mostly cytoplasmic or vacuolar in less differentiated areas. The degree of CA 19-9 expression was inversely related to tumor differentiation (P less than .001).

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1990

Quantitative and qualitative tests for urinary luteinizing hormone. Comparison in spontaneous and clomiphene-citrate-treated cycles.

A study was performed to evaluate conditions in which false-positive and -negative predictions of ovulation occur with qualitative urinary luteinizing hormone (LH) tests. Three urine specimens and a serum sample were collected daily for LH determination from five anovulatory women treated with clomiphene citrate and from six spontaneously cycling women. The urinary LH was determined with one quantitative and three qualitative tests, and the serum LH was determined with a quantitative assay. Ovulation was determined with transvaginal ultrasound and a serum progesterone level on day 22 of the menstrual cycle. There were six ovulatory and five anovulatory cycles. In those 11 cycles the qualitative urinary LH tests were falsely positive twice and falsely negative thrice. All the false-positive and -negative tests except for one occurred when the quantitative urinary LH was 24-28 mIU/mL. Two false-positive tests occurred one to two days after clomiphene administration. Two false-negative tests occurred in a cycle in which follicular development appeared suboptimal, and one occurred in a cycle with a brief urinary LH surge.

Clomiphene↗
PubMed1989

Studies of the HER-2/neu proto-oncogene in human breast and ovarian cancer.

Carcinoma of the breast and ovary account for one-third of all cancers occurring in women and together are responsible for approximately one-quarter of cancer-related deaths in females. The HER-2/neu proto-oncogene is amplified in 25 to 30 percent of human primary breast cancers and this alteration is associated with disease behavior. In this report, several similarities were found in the biology of HER-2/neu in breast and ovarian cancer, including a similar incidence of amplification, a direct correlation between amplification and over-expression, evidence of tumors in which overexpression occurs without amplification, and the association between gene alteration and clinical outcome. A comprehensive study of the gene and its products (RNA and protein) was simultaneously performed on a large number of both tumor types. This analysis identified several potential shortcomings of the various methods used to evaluate HER-2/neu in these diseases (Southern, Northern, and Western blots, and immunohistochemistry) and provided information regarding considerations that should be addressed when studying a gene or gene product in human tissue. The data presented further support the concept that the HER-2/neu gene may be involved in the pathogenesis of some human cancers.

Animals↗
PubMed1989

Binding of radiolabeled estrogens by human cells in vitro: implications to the development of a new diagnostic and therapeutic modality in the treatment of malignancies with estrogen receptors.

An in vitro technique was employed to demonstrate the binding of Auger electron-emitting nuclide-labeled estrogenic compounds by a variety of human cell types. Human granulosa cells, endometrium, and MCF-7 breast cancer cells were incubated with either 16 alpha-[I125]-iodoestradiol-17 beta or 16 alpha-[I123]-iodoestradiol-17 beta in vitro. Autoradiographic techniques were subsequently utilized and revealed that binding of these estrogenic compounds by all three types of cells did occur and that this binding was inhibited by excess unlabeled estradiol. Histologic examination was not able to demonstrate nuclear-specific binding in all instances, however. These compounds are potentially useful in both diagnostic and therapeutic settings and this study is the first to provide such data from human tissue.

Autoradiography↗
PubMed1989

Regulation of progesterone production in the rabbit corpus luteum.

Substantial evidence accumulated over six decades has established that estradiol exerts a dominant stimulatory influence on the production of progesterone by luteal tissue in pseudopregnant or pregnant rabbits, beginning approximately five days after ovulation. The direct steroidogenic action of estradiol on the luteal cell is mediated by the estrogen-receptor protein complex at the nuclear level. Major effects of estradiol lie distal to cholesterol ester and the formation of lipid droplets, and proximal to cholesterol availability for translocation into cytochrome P-450 cholesterol side-chain cleavage enzyme (P-450scc). Structure-function studies corroborate this as an estrogen-sensitive segment of the steroidogenic pathway in the rabbit corpus luteum. Estradiol increases the amount of precursor available for pregnenolone production in rabbit luteal mitochondria. Whether this is because of enhanced precursor storage in the mitochondria or because of effects on intramitochondrial movement of precursor, or both, is unclear. There is a void in knowledge between events at the nuclear level in response to the estrogen stimulus and known post-translational effects at the level of cellular and subcellular organelles. Studies to determine estrogen-sensitive transcriptional and translational events associated with steroidogenesis in the rabbit luteal cell model offer a novel perspective for an improved understanding of the regulatory processes governing steroidogenesis.

Animals↗
PubMed1989

IgG and IgA content of vaginal fluid during the menstrual cycle.

Immunoglobulin levels in cervicovaginal secretions during the menstrual cycle have not been well characterized biochemically. We determined the IgG and IgA concentrations in vaginal fluid obtained by patient self-sampling with an Ovu-Trac aspirator. Vaginal fluid IgG levels were less than 1-270 mg/dL. On the average the levels of IgG were relatively high after menstruation, declined during the ovulatory phase and remained relatively low during most of the luteal phase. The IgA levels were less than 10 mg/dL, and many samples contained IgA at our assay's lower limits of detection (microradial immunodiffusion). The preovulatory and luteal phase levels of IgG and IgA in vaginal fluid were generally lower than those reported for cervical mucus, but the ovulatory phase IgG and IgA composition was comparable between vaginal fluid and cervical mucus.

Body Fluids↗
PubMed1989

Multicenter evaluation of TDx test for assessing fetal lung maturity.

"TDx Fetal Lung Maturity," an automated assay that measures the relative concentrations of surfactant and albumin in amniotic fluid, was compared with the lecithin/sphingomyelin (L/S) ratio and phosphatidylglycerol determination at five clinical sites. A total of 695 amniotic fluid samples were analyzed, of which 312 were followed by delivery of the infant within three days of sample collection. Of these 312, 24 developed respiratory distress syndrome and seven developed transient tachypnea. With the cutoff for maturity set at a surfactant/albumin value of 50 mg/g, the assay showed a sensitivity of 0.96 and a specificity of 0.88 for all samples, compared with a sensitivity of 0.96 and a specificity of 0.83 for the L/S ratio. The combination of rapid assay (30 min), accurate results, and uniformity among testing centers makes the TDx assay a very promising method.

Albumins↗
PubMed1989

Assessment of hormone receptors in breast carcinoma by immunocytochemistry and image analysis. I. Progesterone receptors.

Frozen sections of 30 breast carcinomas were stained for progesterone receptors (PRs) using a rat monoclonal primary antibody and an alkaline phosphatase-antialkaline phosphatase technique. The micro-TICAS image analysis system was used for evaluation of the staining, with the results obtained by image analysis compared with the results of biochemical assays for PR. Strong positive/negative concordance (90%) was observed between the immunohistochemical and biochemical assays. However, the numerical values of the positive cases in the two assays did not correlate well, possibly because the biochemical assay does not take tumor cellularity into account. Three PR distribution patterns, designated A, B and C, were identified by image analysis among the breast tumors. In the type A pattern, tumor cell nuclei were diffusely and uniformly labeled. In type B, both clearly negative as well as distinctly positive cells were present. In type C tumors, a broad range of labeling reactions (from negative to intensely positive) was observed. These results imply (1) that the PR content of human breast carcinoma may be accurately and objectively assessed by the image analysis of immunohistochemically stained frozen sections, (2) that image analysis may provide a more accurate estimate of the cellular content of PR than do biochemical assays and (3) that PR distribution patterns obtained through image analysis permit the consistent appraisal of intratumoral heterogeneity of PR expression, which is potentially of prognostic importance.

Breast Neoplasms↗
PubMed1989

Assessment of hormone receptors in breast carcinoma by immunocytochemistry and image analysis. II. Estrogen receptors.

Frozen sections of 30 invasive breast carcinomas were stained for estrogen receptors (ERs) and the tumor cell proliferative rate by an immunoalkaline phosphatase technique. The stained sections were evaluated for ER by the microTICAS image analysis system. Seventeen tumors were ER positive and 13 were ER negative by image analysis. There was 93% concordance between the ER results obtained by image analysis and those obtained by biochemical methods. One case that was ER negative by image analysis was weakly positive by biochemical assay; a second case was ER positive by image analysis but ER negative by biochemical assay. Twelve of the 17 ER-positive tumors were diffusely positive while 5 displayed considerable intratumoral heterogeneity, with tumor cells exhibiting a broad range of intensity of receptor expression. In most cases, the image analysis ER status coincided with the progesterone receptor (PR) status, but in a large minority of cases (41%) the ER status and the PR status differed. Tumors with a high growth fraction (greater than 30%), as measured by Ki-67 immunostaining, were uniformly ER negative. The results of this investigation suggest that immunohistochemical staining of frozen sections for ER aided by automated image analysis (1) reliably detects the receptor in breast carcinoma, (2) allows for the assessment of heterogeneity within tumors and (3) may be used as part of a panel of antibodies to markers of potential prognostic importance in a single small tissue sample.

Breast Neoplasms↗
PubMed1988

Hyperthermia.

Explore the source record for details and available documents.

Humans↗
PubMed1988

Estrogen increases precursor for pregnenolone synthesis with temperature-sensitive occupancy of P-450scc in mitochondria of rabbit corpus luteum.

To examine the mechanism of estrogen's direct stimulation of steroidogenesis in the rabbit corpus luteum, we tested the hypothesis that the effect of estrogen on progestin production occurs at the site of processing of the precursor for pregnenolone (i.e. cholesterol) in the mitochondrion. For this purpose, we manipulated a model of estrogen stimulation by 1) removing sc estradiol-filled polydimethylsiloxane capsules from superovulated rabbits on day 9 of pseudopregnancy or 2) leaving the capsules in place to preserve a chronic estrogen stimulus. In the estrogen-deprived rabbits, the serum progesterone level fell precipitously in vivo within 24 h, but in rabbits with chronic estrogen stimulation, serum progesterone levels remained high. Our results show that the loss in progestin production caused by estrogen deprivation could not be attributed to loss of the mitochondrial cytochrome P-450 side-chain cleavage enzyme (P-450scc), a common rate-limiting step in progestin synthesis in many steroidogenic tissues. In addition, we confirmed that there was no loss in the catalytic activity of this enzyme. Treatment with aminoglutethimide in vivo followed by electron paramagnetic resonance spectroscopic analysis of mitochondria (prepared in aminoglutethimide-free buffers) showed that incubation of isolated mitochondria at 37 C and pH 6.2 caused an increased high spin state (g = 8.2 signal) and a concomitant decreased low spin state. This shift from low to high spin states, which is indicative of cholesterol-P-450scc complex formation, occurred in the luteal mitochondria from both estrogen-deprived and estrogen-stimulated rabbits. In further studies to localize estrogen's regulatory point, we determined that the initial (first minute) rate of production of pregnenolone (per mg protein or per U P-450scc) from endogenous precursor proceeded equally fast in mitochondria from estrogen-deprived and those from estrogen-stimulated rabbits. However, the rapid pregnenolone production in the estrogen-deprived group lasted for a shorter time and, after 30 min, yielded less pregnenolone per mg protein or per U P-450scc than did mitochondria from estrogen-stimulated rabbits. Addition of 25-hydroxycholesterol did not increase the initial rate of pregnenolone formation, indicating that precursor availability is not limiting during the initial period. In aggregate, these observations suggest that the effect of estrogen on progestin production in the rabbit corpus luteum is not regulation of the movement of cholesterol to the catalytic site on the inner mitochondrial membrane, even though this is a step in the regulation of protein hormone-stimulated steroidogenesis.(ABSTRACT TRUNCATED AT 400 WORDS)

Aminoglutethimide↗
PubMed1987

Serum CA 125 and survival of mice inoculated with ovarian carcinoma and treated with antiestrogen, estrogen, or progestin.

The human ovarian carcinoma cell line NIH-OVCAR-3 grown in immunodeficient mice has been reported to be sensitive to estrogen medications and to express progestin receptor. To assess the effects of sex steroids on CA 125 production and survival times in these mice, we administered Tamoxifen, estrogen, and progestin. During the first 28 days after inoculation of mice with 2.3 million tumor cells ip, serum CA 125 rose exponentially, reaching 4308 +/- 776 and 3905 +/- 1013 units/ml (mean +/- SEM, P greater than 0.1) in placebo- and Tamoxifen-treated mice, respectively; median survival times were 41 and 39 days, respectively (P greater than 0.1). Uninoculated mice had nondetectable CA 125, and all outlived the inoculated mice. In tumor-inoculated mice, serum CA 125 levels and survival were similar when estrogen or progestin was injected alone and when both were given in combination. We detected no significant differences in production of CA 125 in vitro by tumor cells harvested from ascites fluid when the mice were treated with placebo, estrogen, or progestin. We conclude that, for our model, serial measurements of serum CA 125 provide excellent estimates of the relationship between tumor burden and survival, and that CA 125 production appears unaffected by estrogen, progestin, or Tamoxifen.

Animals↗
PubMed1986

Cholesterol metabolism in estrogen-sensitive progestin synthesis by rabbit corpus luteum.

To learn whether either reduced de novo cholesterol synthesis and/or altered cholesteryl ester metabolism is responsible for the deficient progestin production induced by estrogen withdrawal from pseudopregnant rabbits, we measured the luteal activity of three enzymes: 1) 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase (the rate-limiting step in de novo cholesterol synthesis), 2) cholesteryl ester hydrolase, and 3) acyl coenzyme A:cholesterol acyltransferase (ACAT) in estrogen-stimulated and estrogen-deprived rabbits. The only change in the activity of these enzymes and of the enzyme NADPH-cytochrome c reductase (a microsomal marker enzyme) after estrogen capsule removal for 12 or 24 h was a 30% decrease in HMG-CoA reductase activity after 24 h. The decrease in HMG-CoA reductase activity was not accompanied by a detectable change in either the content or localization of cellular free cholesterol. Previous data from our laboratory have demonstrated that 24 h of estrogen deprivation has no effect on inner mitochondrial membrane P-450 side-chain cleavage activity (a rate-limiting step in the conversion of cholesterol to steroid hormones). These data, and our earlier finding that estrogen deprivation leads to accumulation of cholesteryl ester in the luteal cells, indicate that estrogen maintains rabbit luteal progestin production by stimulating the transfer of cytoplasmic cholesterol to the active site of P-450 side-chain cleavage on the inner mitochondrial membrane.

Animals↗
PubMed1986

Enzyme-linked immunochemical measurement of estrogen receptor in gynecologic tumors, and an overview of steroid receptors in ovarian carcinoma.

We tested whether a newly available enzyme-linked immunoassay (EIA) validly measures estrogen receptor (ER) in gynecologic tumors. We first documented that ER so measured agreed with results by established radioligand-based assays [dextran-coated charcoal (DCC) and hydroxylapatite (HAP)] for in-house breast carcinomas and for proficiency testing specimens. Then, for gynecologic tumors, we found strong correlations between results for ER as measured by the two methods; e.g., for 27 ovarian carcinomas, r greater than or equal to 0.86. The same was true for ER measured in nine specimens of ovarian carcinoma from women who had undergone chemotherapy: r greater than or equal to 0.94. Radioinert estradiol or serum had no discernible effect on EIA measurements of ER, whereas our DCC assay was rendered uninterpretable. Evidently the EIA validly measures ER in steroidogenic tissues, including ovarian, and also in breast and uterine carcinomas. Clinical management of the latter is now based in part on results of steroid receptor assays. For ovarian carcinomas, ER assay can be helpful for determining the probable primary site of adenocarcinomas of unknown origin, and it is providing a rational basis for development of new diagnostic and therapeutic strategies.

Blood↗