WISE 2005: Aerobic and resistive countermeasures prevent paraspinal muscle deconditioning during 60-day bed rest in women

Microgravity-induced lumbar paraspinal muscle deconditioning may contribute to back pain commonly experienced by astronauts and may increase the risk of postflight injury. We hypothesized that a combined resistive and aerobic exercise countermeasure protocol that included spinal loading would mitigate lumbar paraspinal muscle deconditioning during 60 days of bed rest in women. Sixteen women underwent 60-day, 6° head-down-tilt bed rest (BR) and were randomized into control and exercise groups. During bed rest the control group performed no exercise. The exercise group performed supine treadmill exercise within lower body negative pressure (LBNP) for 3-4 days/wk and flywheel resistive exercise for 2–3 days/wk. Paraspinal muscle cross-sectional area (CSA) was measured using a lumbar spine MRI sequence before and after BR. In addition, isokinetic spinal flexion and extension strengths were measured before and after BR. Data are presented as means ± SD. Total lumbar paraspinal muscle CSA decreased significantly more in controls (10.9 ± 3.4%) than in exercisers (4.3 ± 3.4%; P < 0.05). The erector spinae was the primary contributor (76%) to total lumbar paraspinal muscle loss. Moreover, exercise attenuated isokinetic spinal extension loss (−4.3 ± 4.5%), compared with controls (−16.6 ± 11.2%; P < 0.05). In conclusion, LBNP treadmill and flywheel resistive exercises during simulated microgravity mitigate decrements in lumbar paraspinal muscle structure and spine function. Therefore spaceflight exercise countermeasures that attempt to reproduce spinal loads experienced on Earth may mitigate spinal deconditioning during long-duration space travel.

Yoga as a treatment for chronic low back pain: A systematic review of the literature

OBJECTIVES

Chronic low back pain (CLBP) affects millions of people worldwide, and appears to be increasing in prevalence. It is associated not only with pain, but also with increased disability, psychological symptoms, and reduced quality of life. There are various treatment options for CLBP, but no single therapy stands out as being the most effective. In the past 10 years, yoga interventions have been studied as a CLBP treatment approach. The objective of this paper is to review the current literature supporting the efficacy of yoga for CLBP.

METHODS

A literature search through the beginning of 2015 was conducted in Pub Med for randomized control trials addressing treatment of CLBP with yoga.

RESULTS

In this review we evaluate the use of yoga as a treatment for CLBP. Specifically we evaluate how yoga impacts physical functioning and disability, pain, and associated psychological symptoms. We also evaluate possible mediators of the effect of yoga and the safety of yoga.

DISCUSSION

With few exceptions, previous studies and the recent randomized control trials (RCTs) indicate that yoga can reduce pain and disability, can be practiced safely, and is well received by participants. Some studies also indicate that yoga may improve psychological symptoms, but these effects are currently not as well established.

An angled insertion technique using 6-mm needles markedly reduces the risk of intramuscular injections in children and adolescents

AIMS

The aims of this study were (i) to establish which children with Type 1 diabetes are at risk of intramuscular or intradermal insulin injections and (ii) to determine a needle length and technique that reliably administers insulin into subcutaneous fat.

METHODS

Seventy-two healthy diabetic children (age 6.3-14.3 years, body mass index standard deviation score 1.0 +/- 1.4) were recruited for study 1 and 37 of this cohort participated in study 2. In study 1, 200 microl air was injected into the abdomen and anterior thigh by a pinched skin-fold technique using either a perpendicular insertion of NovoFine(R) 31G 6-mm or an angled insertion of NovoFine(R) 30G 8-mm needles. In study 2, subjects received injections into abdomen and anterior thigh via angled 6-mm needles with either an unpinched or pinched technique. The site of air injection was visualized by ultrasound scan and measurements taken of subcutaneous fat thickness.

RESULTS

In study 1, intramuscular injections were detected in 32% of subjects, and in a further 22% air was visualized at the muscle fascia. In study 2, intramuscular injections occurred in 3% of subjects and a further 11% had muscle fascia air detected. No intramuscular injections occurred in subjects injecting with a 6-mm needle and an angled pinched skin-fold technique. Pinching abdomen and thigh skin folds increased the subcutaneous fat thickness by 192 +/- 16% and 22 +/- 6%, respectively. In very lean subjects, pinching thighs actually reduced subcutaneous fat thickness.

CONCLUSIONS

While intramuscular injections were observed frequently using standard injection protocols, an angled 6-mm needle technique reliably injects into the subcutaneous fat.

Molecular determinants underlying the formation of stable intracellular G protein-coupled receptor-beta-arrestin complexes after receptor endocytosis*

beta-Arrestins bind agonist-activated G protein-coupled receptors (GPCRs) and mediate their desensitization and internalization. Although beta-arrestins dissociate from some receptors at the plasma membrane, such as the beta2 adrenergic receptor, they remain associated with other GPCRs and internalize with them into endocytic vesicles. Formation of stable receptor-beta-arrestin complexes that persist inside the cell impedes receptor resensitization, and the aberrant formation of these complexes may play a role in GPCR-based diseases (Barak, L. S., Oakley, R. H., Laporte, S. A., and Caron, M. G. (2001) Proc. Natl. Acad. Sci. U. S. A. 98, 93-98). Here, we investigate the molecular determinants responsible for sustained receptor/beta-arrestin interactions. We show in real time and in live human embryonic kidney (HEK-293) cells that a beta-arrestin-2-green fluorescent protein conjugate internalizes into endocytic vesicles with agonist-activated neurotensin-1 receptor, oxytocin receptor, angiotensin II type 1A receptor, and substance P receptor. Using receptor mutagenesis, we demonstrate that the ability of beta-arrestin to remain associated with these receptors is mediated by specific clusters of serine and threonine residues located in the receptor carboxyl-terminal tail. These clusters are remarkably conserved in their position within the carboxyl-terminal domain and serve as primary sites of agonist-dependent receptor phosphorylation. In addition, we identify a beta-arrestin mutant with enhanced affinity for the agonist-activated beta2-adrenergic receptor that traffics into endocytic vesicles with receptors that lack serine/threonine clusters and normally dissociate from wild-type beta-arrestin at the plasma membrane. By identifying receptor and beta-arrestin residues critical for the formation of stable receptor-beta-arrestin complexes, these studies provide novel targets for regulating GPCR responsiveness and treating diseases resulting from abnormal GPCR/beta-arrestin interactions.

Addition of casein or whey protein to colostrum or a colostrum supplement product on absorption of IgG in neonatal calves

The effects of the addition of nonimmunoglobulin protein on absorption of immunoglobulin G (IgG) from colostrum or colostrum supplement products were determined in two experiments. In experiment 1, 48 Holstein calves were fed 4 L of pooled maternal colostrum or 4 L of reconstituted colostrum supplement with 0, 200, or 400 g of added whey protein concentrate or casein. In experiment 2, 38 Jersey calves were fed 2 L of pooled maternal colostrum with 100 or 200 g of whey protein concentrate or casein added immediately before feeding. Blood was collected at 24 h of age and plasma IgG concentration, total protein, hematocrit (experiment 1 only), and plasma urea N were determined. In experiment 1, blood samples were also collected at 4, 8, 12, 16, and 20 h to evaluate absorption of IgG and protein and urea N concentrations. The addition of 400 g of casein to colostrum supplement in experiment 1 reduced plasma IgG from 5.66 g/L (0 g of casein addition) to 3.88 g/L, increased plasma urea N at 24 h, and reduced the change in plasma total protein from 0 to 24 h. Hourly plasma IgG concentrations increased with the consumption of colostrum or supplements but increased more rapidly in calves fed whey protein concentrate and more slowly in calves fed casein. The addition of 200 g of casein or whey protein concentrate to colostrum supplements had no effect on plasma IgG concentration at 24 h of age. The addition of 100 or 200 g of casein or whey protein concentrate to maternal colostrum had no effect on plasma urea N, total protein, or plasma IgG in experiment 2. The addition of nonimmunoglobulin protein to colostrum supplements or maternal colostrum did not affect IgG absorption from the intestine of newborn calves unless the amount of total protein exceeded 500 g of protein.

The interaction of beta-arrestin with the AP-2 adaptor is required for the clustering of beta 2-adrenergic receptor into clathrin-coated pits

Beta-arrestins are cytosolic proteins that regulate the signaling and the internalization of G protein-coupled receptors (GPCRs). Although termination of receptor coupling requires beta-arrestin binding to agonist-activated receptors, GPCR endocytosis involves the coordinate interactions between receptor-beta-arrestin complexes and other endocytic proteins such as adaptor protein 2 (AP-2) and clathrin. Clathrin interacts with a conserved motif in the beta-arrestin C-terminal tail; however, the specific molecular determinants in beta-arrestin that bind AP-2 have not been identified. Moreover, the respective contributions of the interactions of beta-arrestin with AP-2 and clathrin toward the targeting of GPCRs to clathrin-coated vesicles have not been established. Here, we identify specific arginine residues (Arg(394) and Arg(396)) in the beta-arrestin 2 C terminus that mediate beta-arrestin binding to AP-2 and show, in vitro, that these domains in beta-arrestin 1 and 2 interact equally well with AP-2 independently of clathrin binding. We demonstrate in HEK 293 cells by fluorescence microscopy that beta(2)-adrenergic receptor-beta-arrestin complexes lacking the beta-arrestin-clathrin binding motif are still targeted to clathrin-coated pits. In marked contrast, receptor-beta-arrestin complexes lacking the beta-arrestin/AP-2 interactions are not effectively compartmentalized in punctated areas of the plasma membrane. These results reveal that the binding of a receptor-beta-arrestin complex to AP-2, not to clathrin, is necessary for the initial targeting of beta(2)-adrenergic receptor to clathrin-coated pits.

Differential affinities of visual arrestin, beta arrestin1, and beta arrestin2 for G protein-coupled receptors delineate two major classes of receptors

Visual arrestin, betaarrestin1, and betaarrestin2 comprise a family of intracellular proteins that desensitize G protein-coupled receptors (GPCRs). In addition, betaarrestin1 and betaarrestin2 target desensitized receptors to clathrin-coated pits for endocytosis. Whether arrestins differ in their ability to interact with GPCRs in cells is not known. In this study, we visualize the interaction of arrestin family members with GPCRs in real time and in live cells using green fluorescent protein-tagged arrestins. In the absence of agonist, visual arrestin and betaarrestin1 were found in both the cytoplasm and nucleus of HEK-293 cells, whereas betaarrestin2 was found only in the cytoplasm. Analysis of agonist-mediated arrestin translocation to multiple GPCRs identified two major classes of receptors. Class A receptors (beta2 adrenergic receptor, mu opioid receptor, endothelin type A receptor, dopamine D1A receptor, and alpha1b adrenergic receptor) bound betaarrestin2 with higher affinity than betaarrestin1 and did not interact with visual arrestin. In contrast, class B receptors (angiotensin II type 1A receptor, neurotensin receptor 1, vasopressin V2 receptor, thyrotropin-releasing hormone receptor, and substance P receptor) bound both betaarrestin isoforms with similar high affinities and also interacted with visual arrestin. Switching the carboxyl-terminal tails of class A and class B receptors completely reversed the affinity of each receptor for the visual and non-visual arrestins. In addition, exchanging the betaarrestin1 and betaarrestin2 carboxyl termini reversed their extent of binding to class A receptors as well as their subcellular distribution. These results reveal for the first time marked differences in the ability of arrestin family members to bind GPCRs at the plasma membrane. Moreover, they show that visual arrestin can interact in cells with GPCRs other than rhodopsin. These findings suggest that GPCR signaling may be differentially regulated depending on the cellular complement of arrestin isoforms and the ability of arrestins to interact with other cellular proteins.

Association of beta-arrestin with G protein-coupled receptors during clathrin-mediated endocytosis dictates the profile of receptor resensitization

Resensitization of G protein-coupled receptors (GPCRs) following agonist-mediated desensitization is a necessary step for maintaining physiological responsiveness. However, the molecular mechanisms governing the nature of GPCR resensitization are poorly understood. Here, we examine the role of beta-arrestin in the resensitization of the beta(2) adrenergic receptor (beta(2)AR), known to recycle and resensitize rapidly, and the vasopressin V2 receptor (V2R), known to recycle and resensitize slowly. Upon agonist activation, both receptors recruit beta-arrestin to the plasma membrane and internalize in a beta-arrestin- and clathrin-dependent manner. However, whereas beta-arrestin dissociates from the beta(2)AR at the plasma membrane, it internalizes with the V2R into endosomes. The differential trafficking of beta-arrestin and the ability of these two receptors to dephosphorylate, recycle, and resensitize is completely reversed when the carboxyl-terminal tails of these two receptors are switched. Moreover, the ability of beta-arrestin to remain associated with desensitized GPCRs during clathrin-mediated endocytosis is mediated by a specific cluster of phosphorylated serine residues in the receptor carboxyl-terminal tail. These results demonstrate that the interaction of beta-arrestin with a specific motif in the GPCR carboxyl-terminal tail dictates the rate of receptor dephosphorylation, recycling, and resensitization, and thus provide direct evidence for a novel mechanism by which beta-arrestins regulate the reestablishment of GPCR responsiveness.

The beta2-adrenergic receptor/betaarrestin complex recruits the clathrin adaptor AP-2 during endocytosis

betaarrestins mediate the desensitization of the beta2-adrenergic receptor (beta2AR) and many other G protein-coupled receptors (GPCRs). Additionally, betaarrestins initiate the endocytosis of these receptors via clathrin coated-pits and interact directly with clathrin. Consequently, it has been proposed that betaarrestins serve as clathrin adaptors for the GPCR family by linking these receptors to clathrin lattices. AP-2, the heterotetrameric clathrin adaptor protein, has been demonstrated to mediate the internalization of many types of plasma membrane proteins other than GPCRs. AP-2 interacts with the clathrin heavy chain and cytoplasmic domains of receptors such as those for epidermal growth factor and transferrin. In the present study we demonstrate the formation of an agonist-induced multimeric complex containing a GPCR, betaarrestin 2, and the beta2-adaptin subunit of AP-2. beta2-Adaptin binds betaarrestin 2 in a yeast two-hybrid assay and coimmunoprecipitates with betaarrestins and beta2AR in an agonist-dependent manner in HEK-293 cells. Moreover, beta2-adaptin translocates from the cytosol to the plasma membrane in response to the beta2AR agonist isoproterenol and colocalizes with beta2AR in clathrin-coated pits. Finally, expression of betaarrestin 2 minigene constructs containing the beta2-adaptin interacting region inhibits beta2AR endocytosis. These findings point to a role for AP-2 in GPCR endocytosis, and they suggest that AP-2 functions as a clathrin adaptor for the endocytosis of diverse classes of membrane receptors.

Transmembrane protein insertion orientation in yeast depends on the charge difference across transmembrane segments, their total hydrophobicity, and its distribution

The determinants of transmembrane protein insertion orientation at the endoplasmic reticulum have been investigated in Saccharomyces cerevisiae using variants of a Type III (naturally exofacial N terminus (Nexo)) transmembrane fusion protein derived from the N terminus of Ste2p, the alpha-factor receptor. Small positive and negative charges adjacent to the transmembrane segment had equal and opposite effects on orientation, and this effect was independent of N- or C-terminal location, consistent with a purely electrostatic interaction with response mechanisms. A 3:1 bias toward Nexo insertion, observed in the absence of a charge difference, was shown to reflect the Nexo bias conferred by longer transmembrane segments. Orientation correlated best with total hydrophobicity rather than length, but it was also strongly affected by the distribution of hydrophobicity within the transmembrane segment. The most hydrophobic terminus was preferentially translocated. Insertion orientation thus depends on integration of responses to at least three parameters: charge difference across a transmembrane segment, its total hydrophobicity, and its hydrophobicity gradient. Relative signal strengths were estimated, and consequences for topology prediction are discussed. Responses to transmembrane sequence may depend on protein-translocon interactions, but responses to charge difference may be mediated by the electrostatic field provided by anionic phospholipids.

Estrogen-mediated mitochondrial cholesterol transport and metabolism to pregnenolone in the rabbit luteinized ovary

We investigated the mechanisms of luteotropic actions of estradiol on steroidogenesis. To this end, we examined, in vitro, the metabolism of cholesterol from endogenous or exogenous sources for pregnenolone production in rabbit luteinized ovarian cell mitochondria isolated from pseudopregnant animals in various states of stimulation by estradiol. We found that estradiol-mediated regulation of mitochondrial cholesterol metabolism for pregnenolone production differs from the mechanisms of regulation reported for steroidogenic protein/polypeptide hormones in the following respects: 1) in the estradiol-sensitive, luteinized-ovary, rabbit model, temporary blockage of cytochrome P-450 cholesterol side-chain cleavage enzyme by aminoglutethimide treatment in vivo has no effect on mitochondrial pregnenolone production in vitro after the aminoglutethimide is removed, indicating no additional capacity for upstream cholesterol storage; 2) preincubating mitochondria at 37 degrees C fails to increase subsequent pregnenolone synthesis in response to the addition of isocitrate; and 3) exogenously added cholesterol does not readily enter the steroidogenic pool of cholesterol unless the endogenous cholesterol pool is first depleted. These new observations indicate that estradiol increases the usable steroidogenic cholesterol pool in rabbit ovarian mitochondria. Also, 1) they are consistent with a putative requirement for the participation of one or more estrogen-sensitive protein factors to enhance cholesterol trafficking to the inner mitochondrial membrane, and 2) they complement the observation of estrogen-dependent expression of steroidogenic acute regulatory protein in rabbit luteal tissue.

Regulation of expression of the steroidogenic acute regulatory protein (StAR) gene: a central role for steroidogenic factor 1

Steroidogenic acute regulatory protein (StAR) plays a critical role in regulating the rate-limiting step in steroid hormone synthesis, cholesterol side-chain cleavage. StAR gene expression is transcriptionally controlled in the gonads by gonadotropic hormones via a cAMP second message. We have begun to analyze factors responsible for the transcriptional activation of the StAR gene. The human StAR gene promoter has at least two cis elements that govern basal and cAMP-regulated gene expression. One of these elements (the distal element) is a consensus binding sequence for the orphan nuclear receptor transcription factor, steroidogenic factor 1 (SF-1); the other (the proximal element) is a related motif. The human StAR promoter is not active in BeWo choriocarcinoma cells, but is functional and cAMP-responsive in murine Y1 adrenal cortical tumor cells. Cotransfection of a plasmid expressing SF-1 allows a StAR promoter construct to function in BeWo cells. Other orphan nuclear transcription factors do not support StAR promoter function in BeWo cell hosts. Deletion or mutation of the distal and proximal cis elements individually substantially reduces SF-1-supported StAR promoter activity. The distal site binds SF-1 with high affinity, whereas the proximal site binds SF-1 with lower affinities. These findings demonstrate a requirement for SF-1 for human StAR gene expression.

Steroidogenic acute regulatory protein (StAR) retains activity in the absence of its mitochondrial import sequence: implications for the mechanism of StAR action

Steroidogenic acute regulatory protein (StAR) plays a critical role in steroid hormone biosynthesis, presumably by facilitating the delivery of cholesterol to P450scc in the inner mitochondrial membranes. StAR is synthesized as a 37-kDa preprotein that is processed to a 30-kDa mature form by cleavage of an N-terminal mitochondrial import sequence. To identify structural features required for StAR biological activity, we mutated the human StAR cDNA, including the deletion of N- and C-terminal sequences, and examined the ability of the mutants to promote steroidogenesis and enter the mitochondria of transfected COS-1 cells. Deletion of up to 62 residues from the N terminus (N-62) did not significantly affect steroidogenesis-enhancing activity. The N-terminal deletion mutants were associated with mitochondria-enriched fractions, but import and processing were progressively impaired with increasing length of the deletion. Immunogold electron microscopy and in vitro import assays showed that the active N-62 mutant was not imported into the mitochondria. Removal of the 28 C-terminal amino acids (C-28) inactivated StAR. Deletion of the C-terminal 10 amino acids (C-10) reduced steroidogenic activity by 53%, while truncation of the last 4 amino acids had no effect. The C-28 mutant StAR was not efficiently imported into mitochondria or processed, whereas some of the C-10 mutant was processed, indicating that import had occurred. We conclude that in the COS-1 cell system used, StAR does not need to enter into mitochondria to stimulate steroidogenesis and that residues in the C terminus are essential for steroidogenesis-enhancing activity. These findings imply that StAR acts via C-terminal domains on the outside of the mitochondria.

Steroidogenic factor 1-dependent promoter activity of the human steroidogenic acute regulatory protein (StAR) gene

Steroidogenic acute regulatory protein (StAR) is required for efficient adrenal cortical and gonadal but not trophoblast steroid hormone synthesis. StAR gene expression in gonadal cells is stimulated by tropic hormones acting through the intermediacy of cAMP. DNA sequence analysis of the human StAR gene promoter revealed two motifs resembling binding sites for steroidogenic factor 1 (SF-1), a member of the orphan nuclear receptor transcription factor family that controls expression of steroidogenic hydroxylases. The 5'-most sequence (distal site) is a consensus SF-1 binding site. The proximal site is a consensus estrogen receptor binding half-site. The StAR gene promoter is not active in BeWo choriocarcinoma cells, COS-1 cells, HeLa cells, or SK-OV-3 ovarian adenocarcinoma cells, all of which do not express significant levels of SF-1 mRNA. Introduction of SF-1 into these cells stimulated StAR promoter activity, particularly in response to cAMP. Two orphan nuclear transcription factors that bind to sequences similar to SF-1 sites, NGFI-B/Nur77 and RNR-1, did not support cAMP-stimulated StAR promoter activity in BeWo cells. Mutation of the distal putative SF-1 binding site reduced basal and cAMP-stimulated promoter activity in BeWo cells by 82% and 71%, respectively. Mutation of the proximal putative SF-1 binding site reduced basal and cAMP-stimulated promoter activity by 89% and 96%, respectively. Mutations in both sites reduced basal promoter activity to 7% of wild type promoter activity and cAMP-stimulated promoter activity to less than 5% of the wild type. Deletion analyses of promoter activity were consistent with the mutation studies. Electrophoretic mobility shift assays (EMSAs) demonstrated that the distal site binds to SF-1 expressed in COS-1 cells and to an SF-1-GST fusion protein with high affinity, but that the mutated distal sequence does not. An anti-SF-1 antibody ablated the characteristic SF-1-DNA complex with the distal sequence. The proximal site formed a number of protein-DNA complexes with COS-1 cell extracts, but appeared to have at best only very modest affinity for SF-1. Collectively, our findings demonstrate that SF-1 plays a key role in controlling the basal and cAMP-stimulated expression of the StAR gene. SF-1 can function at two distinct sites in the human StAR gene promoter, apparently by two different types of interaction, to control transcription.

Accelerated fetal lung maturity profiles and maternal cocaine exposure

OBJECTIVE

To determine the effect of maternal cocaine exposure on fetal lung maturity as measured by surfactant-albumin ratios determined by the TDx-FLM test.

METHODS

A case-control study design was used to compare fetal lung maturity as assessed by a surfactant-albumin ratio assay (TDx-FLM) in amniotic fluid (AF) obtained from women who were known to use cocaine and those who were not known to use cocaine during the study pregnancy. Multiple logistic regression procedures were used to control for gestational age and possible confounders, such as obstetric and nonobstetric complications, other substance abuse, race, infant sex, and payer status.

RESULTS

Maternal cocaine use during pregnancy was associated with an accelerated fetal lung maturity profile (adjusted odds ratio [OR] 2.04, 95% confidence interval [CI] 1.04-4.00) as determined by the TDx-FLM test. Other variables found to be statistically significant predictors of a mature fetal lung profile were cigarette smoking during the current pregnancy (OR 1.61, 95% CI 1.02-2.56). Preterm labor, preterm rupture of membranes, nonobstetric illness during pregnancy, and exposure to other abused substances were not associated with accelerated fetal lung maturity.

CONCLUSION

Maternal cocaine use during pregnancy is associated with a doubling of the probability of a mature fetal lung profile as determined by TDx-FLM analysis of AF. Tobacco use is also a predictor of accelerated fetal lung maturity profiles.

T-->A transversion 11 bp from a splice acceptor site in the human gene for steroidogenic acute regulatory protein causes congenital lipoid adrenal hyperplasia

Congenial lipoid adrenal hyperplasia (lipoid CAH) is the most severe form of CAH. Affected individuals can make no adrenal or gonadal steroids. All affected individuals are phenotypic females irrespective of gonadal sex, and frequently die in infancy if mineralocorticoid and glucocorticoid replacements are not instituted. Recent data implicate the steroidogenic acute regulatory (StAR) protein in this disorder. We now describe a 46,XY patient of Vietnamese ancestry with lipoid CAH who had a somewhat milder form of the disease. Diagnosis was at 10 weeks of age, and low levels of plasma progesterone, corticosterone, 180H-corticosterone and androstenedione were detectable. Testicular RNA for StAR was reverse transcribed, amplified, cloned and sequenced, revealing a 185 bp deletion corresponding to all of exon 5. The corresponding mRNA did not encode active protein in transfected cells. Cloned genomic DNA from the patient revealed only a T-->A transversion in intron 4,11 bp from the splice acceptor site of exon 5. This transversion destroys an NcoI site; digestion of PCR-amplified genomic DNA from the patient and both parents confirmed that the patient was homozygous and the parents were heterozygous. Expression vectors for StAR minigenes were constructed containing all StAR exons plus introns 4, 5 and 6 either with or without the T-->A mutation in intron 4. RNase protection assays showed that expression of the vector with normal intron 4 yielded correctly spliced StAR mRNA in transfected COS-1 cells, while most, but not all StAR mRNA from the vector with the T-->A transversion in intron 4 was abnormally spliced. RNase protection of the patient's testicular RNA confirmed that most, but not all StAR mRNA was similarly spliced abnormally. Splicing errors appear to be a rare cause of genetic diseases, but subtle intronic mutations may be missed when genomic DNA is the only material available for study. The low level of normal StAR mRNA produced may account for the later clinical presentation and low levels of steroid hormones detected in this patient.

Structure of the human steroidogenic acute regulatory protein (StAR) gene: StAR stimulates mitochondrial cholesterol 27-hydroxylase activity

Steroidogenic acute regulatory protein (StAR) plays a key role in steroid hormone synthesis by enhancing the metabolism of cholesterol into pregnenolone. We determined the organization of the StAR structural gene, mapped to 8p11.2. The gene spans 8 kb and consists of seven exons interrupted by six introns. The 1.3 kb of DNA upstream from the transcription start site directed expression of a luciferase reporter gene in mouse Y-1 adrenal cortical tumor cells but not in BeWo choriocarcinoma cells. Reporter gene expression in the Y-1 cells was increased more than 2-fold by 8-Br-cAMP, indicating that the 1.3 kb DNA fragment contains sequences that confer tissue-specific expression and cAMP regulation. The sequence of a related StAR pseudogene, mapped to chromosome 13, lacks introns and has an insertion, numerous substitutions, and deletions. Expression of StAR in COS-1 cells cotransfected with cholesterol 27-hydroxylase (P450c27) and adrenodoxin resulted in a 6-fold increase in formation of 3 beta-hydroxy-5-cholestenoic acid, demonstrating that StAR's actions are not specific to steroidogenesis but extend to other mitochondrial cholesterol-metabolizing enzymes.

Some characteristics of the glutathione cycle revealed by ionising and non-ionising electromagnetic radiation

The cyclic reaction of GSH-->GSSG-->GSH (designated R(exp) or R(e)) obeys the three specific features of life by producing energy in exponential quantities relative to time, is in effect irreversible and is inherited from generation to generation. In multicellular life, this reaction produces the energy for mitosis and is kept in controlled inactivity until needed to maintain perfection of form and function by energising mitosis. The immediate control of Re appears to be feedback process-dependent on the concentration of GSSG. Ultra high-frequency electromagnetic radiation of 434 MHz (UHF) will change Re from inactive to active and, in so doing, it causes resonance and/or fluorescence of the glutathione cycle which changes its radiosensitivity. Re is the primary direct target of ionising radiation and produces the energy for mitosis. Clinical observations suggest that, in the normal cell, Re is inactive and is not killed by 3 x 2700 rads or 6 x 1650 rads yet, when active, its sensitivity value (DO) is approximately 160 rads. Using the standard radiobiological equation of response to ionising radiation, it can be deduced that radiosensitive cancers have two or three Re units active per cell and radioresistance increases in proportion to the number of potentially active Re units per cell. Re appears to be the main cause of cancers' increased conductivity of electricity compared with normal tissue. In cancer therapy, UHF is the best radiosensitiser ever discovered (up to two or more decades). Re is also intelligent compared with non-exponential reactions but cannot be the basis of intellectual brain functions which must be based on non-electrical chemical processes.

Human sterol carrier protein x/sterol carrier protein 2 gene has two promoters

The human sterol carrier protein x (SCPx)/sterol carrier protein 2 (SCP2) gene gives rise to two mRNAs: a 2.8 kb mRNA encoding SCPx, a peroxisome-associated thiolase, and a 1.5 kb mRNA encoding SCP2, which is thought to be an intracellular lipid transfer protein. The SCPx/SCP2 gene is highly expressed in organs involved in lipid metabolism, but the relative abundance of SCPx and SCP2 mRNAs varies. Here we report that the two transcripts are produced under the direction of two independent promoters. We determined the DNA sequence of 3.4 kb of the proximal promoter governing the transcription of SCPx sequences. The promoter governing the transcription of SCP2 sequences was identified 45 kb downstream from the SCPx promoter in intron XI. This promoter initiates transcription within exon XII. Both the SCPx and SCP2 promoters lack TATA boxes and initiate transcription at multiple sites. They share features that are found in the promoters of genes encoding other peroxisomal proteins. The basal activities of the two promoters were tested as fusion gene constructs in selected host cells, including BeWo choriocarcinoma cells, HepG2 hepatoblastoma cells, murine Y1 adrenocortical tumor cells, and Balb 3T3 fibroblasts. Cell host-specific patterns of promoter activity were observed. In addition, 8-Br-cAMP and phorbol myristate acetate were found to increase SCPx promoter activity in a host cell-specific manner. The SCP2 promoter was not significantly influenced by these agents.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical detection of epidermal growth factor receptor lacks prognostic significance for breast carcinoma

OBJECTIVE

We sought to determine whether the immunohistochemical detection of epidermal growth factor receptor (EGF-R) in primary cancer tissues is of prognostic significance in patients with breast carcinoma.

METHODS

Paraffin-embedded tissues from 244 study subjects with primary breast carcinomas were tested immunohistochemically for the presence of EGF-R and were compared in a retrospective study with clinical outcome.

RESULTS

Epidermal growth factor receptor was detected in the tumors of 49 (20.1%) of the 244 study subjects. The incidence of EGF-R detection was comparable in subjects with disease-free lymph nodes (T1-4, N0, M0, n = 111; EGF-R present 22.5%) or those whose nodes contained carcinoma (T1-4, N+, M0, n = 133; EGF-R present 18.9%). No reliable correlation was found in either group between EGF-R detection and clinical, functional, or morphologic prognostic indicators that included age, menopausal status, tumor size, tumor grade, nodal status, and hormone receptor status. Relapse-free survival and overall survival (median observation time 62.5 months) did not differ between patients with EGF-R-positive or EGF-R-negative breast carcinoma specimens.

CONCLUSIONS

In our experience, the immunohistochemical determination of EGF-R in routine formalin-fixed, paraffin-embedded tumor specimens fails to provide useful information concerning the prognosis of patients with primary breast carcinoma.

Human steroidogenic acute regulatory protein: functional activity in COS-1 cells, tissue-specific expression, and mapping of the structural gene to 8p11.2 and a pseudogene to chromosome 13

Steroidogenic acute regulatory protein (StAR) appears to mediate the rapid increase in pregnenolone synthesis stimulated by tropic hormones. cDNAs encoding StAR were isolated from a human adrenal cortex library. Human StAR, coexpressed in COS-1 cells with cytochrome P450scc and adrenodoxin, increased pregnenolone synthesis > 4-fold. A major StAR transcript of 1.6 kb and less abundant transcripts of 4.4 and 7.5 kb were detected in ovary and testis. Kidney had a lower amount of the 1.6-kb message. StAR mRNA was not detected in other tissues including placenta. Treatment of granulosa cells with 8-bromo-adenosine 3',5'-cyclic monophosphate for 24 hr increased StAR mRNA 3-fold or more. The structural gene encoding StAR was mapped using somatic cell hybrid mapping panels to chromosome 8p. Fluorescence in situ hybridization placed the StAR locus in the region 8p11.2. A StAR pseudogene was mapped to chromosome 13. We conclude that StAR expression is restricted to tissues that carry out mitochondrial sterol oxidations subject to acute regulation by cAMP and that StAR mRNA levels are regulated by cAMP.

Comparisons of radioiodoestradiol blood-tissue exchange after intravenous or intraarterial injection

PURPOSE

Our study determines and compares how the major organs of large animals handle exogenous halogenated bioactive sex steroids within the first minutes after their i.v. or i.a. injection. The rationale is that an understanding is needed of the acute physiological events because they affect decisions for how to optimize delivery of radiohalogenated sex steroid receptor ligands for purposes of medical imaging and modes of radiotherapy.

METHODS AND MATERIALS

We used an indicator dilution technique that allows monitoring of blood-tissue exchange of radioactivity in a continuous manner in anesthetized surgically prepared swine.

RESULTS

In swine, with by-passed liver circulation, the lungs allow the vast majority of [I-125]-16 alpha-iodo-17 beta-estradiol ([I-125]E) to be extracted from the blood perfusing the lung in the initial transit after i.v. injection in vivo. Similar outcome was observed for most major organs, including the CNS, intestines, spleen, peripheral appendages, and kidneys after i.a. injection of [I-125]E in vivo. However, within minutes the organs released the [I-125]E in its original chemical form back into the vascular system, with the exception of estrogen receptor (ER) rich tissues and the kidneys that retained the [I-125]E in its original form, although in the kidneys a nonpolar metabolite also accumulated.

CONCLUSION

Our experiments confirm in a large animal model that radioiodoestradiol can be sequestered or concentrated in ER-rich sites. The liver and sex steroid receptor-rich organs modify considerably, by metabolism and sequestration, respectively, the acute distribution of bioactive steroids. Our data indicate potential for detection of ER in vivo in hormone-sensitive tumors, that is, in breast and endometrial cancers, and offer improved understanding of the recent studies in subjects with breast cancer that demonstrated that receptor imaging in vivo of steroid receptors with high-affinity radiolabeled ligands is possible in a clinical setting.

Efficiency of screening procedures for assigning levels of the Stanford Achievement Test (eighth edition) to students who are deaf or hard of hearing

Assignment to an appropriate test level is crucial to the validity of standardized test scores. The present study examined the efficiency of the Reading Screening Tests and Mathematics Screening Tests developed by the Center for Assessment and Demographic Studies (CADS) of Gallaudet University for assigning levels of the Stanford Achievement Test, 8th edition (SAT-8), to deaf and hard-of-hearing students. Data were collected from programs participating in the 1990 test standardization with this population. It was found that while the screening procedures provide a credible means of assigning test levels, they are more effective for the SAT-8's Reading Comprehension, Total Language, Mathematics Computation, and Mathematics Applications subtests than for the Spelling and Concepts of Number subtests. This article concludes with recommendations in regard to individual subtest assignments.

The structure of the human sterol carrier protein X/sterol carrier protein 2 gene (SCP2)

Sterol carrier protein X (SCPx) is a 58-kDa protein that is localized to peroxisomes. The amino acid sequence of the protein suggests that SCPx may function as a thiolase. The gene encoding SCPx also codes for a 15.3-kDa protein called sterol carrier protein 2 (SCP2). Here we report the structure of this gene (SCP2), which spans approximately 80 kb and consists of 16 exons and 15 introns. Multiple transcription start sites were identified. The 5' flanking region has characteristics of other peroxisomal protein promoters, which include the absence of a TATA box and a G+C-enriched region containing several reverse GC boxes.

CA-125 in peritoneal fluid from patients with nonmalignant gynecologic disorders

To assess the diagnostic value of measuring CA-125 levels in peritoneal fluid from women with nonmalignant gynecologic disorders, we determined CA-125 levels in peritoneal fluid and in serum collected simultaneously from 46 women undergoing gynecologic surgery. Patients with benign ovarian disease, non-ovarian gynecologic pathology and severe endometriosis had, on average, higher CA-125 levels in peritoneal fluid than did patients with a normal pelvis and those with mild endometriosis. There was no obvious correlation between peritoneal fluid and serum levels of CA-125. Our data show that (1) measurement of serum CA-125 levels is not useful for distinguishing between different benign gynecologic disorders, and (2) levels of CA-125 in peritoneal fluid in benign gynecologic disorders are comparable to the reported lower range of levels observed in women with intraperitoneal malignancies.

Rapid vascular escape of arterially injected 16 alpha-radioiodo,17 beta-estradiol

PURPOSE

We undertook this study because confirmation of a rapid vascular escape and slow release back into the circulatory system suggests that arterial injection of radiohalogenated steroid receptor ligands might provide an efficacious route of administration for imaging or treatment of receptor-rich malignant tumors in peripheral tissues.

METHODS AND MATERIALS

We injected radiolabeled 16 alpha-iodo,17 beta-estradiol ([I]-E), an estrogen receptor ligand, into the femoral artery of swine in a solution that contained [125I]-E in a known ratio to [99mTc]-labeled red blood cells. Fractions of femoral venous blood were collected at short intervals during 10 min. We looked for changes in the ratio of the radiolabels. [99mTc]-labeled red blood cells are known to remain in the vascular system for an hour or more.

RESULTS

After passage of the injectate through the capillary bed of the swine leg, a dramatic decrease of the initial 125I:99mTc ratio to only 10% was observed in the femoral venous blood. This ratio increased gradually during the next 10 min to approximately 30% of that in the injectate, indicating that a significant portion (approximately 90%) of the [125I]-E was initially trapped in the limb and then slowly re-entered the vascular system. To obtain visual confirmation of the rapid vascular escape of iodo-estrogen, we injected either an imageable form of [I]-E (123I]-E) or [99mTc]-labeled red blood cells into the dorsal aorta of superovulated rabbits, whose smaller size allowed whole-body imaging. The biodistributions of these radiopharmaceuticals were surveyed continuously by real-time planar gamma imaging. Within 2 min after the injection of [123I]-E, the outlines of the circulatory system were entirely lost; however, some estrogen receptor-rich tissues (the ovaries) as well as some non-target tissues, for example, the lower leg extremities, yielded well-defined images. In contrast, after intra-arterial injection of [99mTc]-labeled red blood cells, the circulatory system remained sharply defined for the duration of the study (40 min).

CONCLUSION

A large fraction of [I]-E escapes from the vascular system during the first pass through an organ or limb, without regard to the estrogen receptor content of the tissue.

The glutathione cycle is the creative reaction of life and cancer. Cancer causes oncogenes and not vice versa

Life is definable as a chemical reaction which obeys exponential growth and dies if reversed. Such a reaction must be the commencement of all life so that every evolved form of it inherits these characteristics. As no single reaction known has these two features, life must be a combination of two or more reactions which whilst obeying all the classical laws of physics and chemistry assume an exponential form and effectively act as being irreversible. The reactions of glutathione--oxidation and reduction--when combined in sequence as a cyclical process fulfill these criteria. The cyclic changes of glutathione from reduced to oxidised to reduced forms must therefore be the reaction which creates life and is responsible for cancer's growth. 434 mHz electromagnetic radiation stimulates cancer growth rate by forcing this cycle into activity. Proof of this hypothesis is the long-term control of cancer in 11 patients treated with oxidised glutathione and 434 mHz radiation. Genetic material does not contain any energy system with exponential form, neither is it self-replicating. Genetic material will only reproduce if placed within an immortal cell in which all controls of the glutathione system have been lost, as in a cancer cell. Oncogenes must be the product of cancer and not the reverse.

Breaks in DNA accompany estrogen-receptor-mediated cytotoxicity from 16 alpha[125I]iodo-17 beta-estradiol

Strategies for diagnosis and therapy in which sex steroid receptor ligands serve as carriers for radionuclides are attractive because a high incidence of carcinomas of the female genital tract and the breast that are seen clinically have an abundant expression of one or more of the receptor proteins. A radiohalogenated estrogen receptor (ER) ligand, 16 alpha-[123I]iodo-17 beta-estradiol [123I]E, has met clinical criteria for receptor-mediated diagnostic imaging. Its [125]I-labeled sister nuclide derivative [125I]E decays by orbital electron capture with emission of very-low-energy (Auger) electrons, which gives this latter radiohalogen the potential to serve in pharmaceuticals for radiotherapy; as examples, [125I]deoxyuridine, when incorporated into the DNA molecule, or [125I]E, when bound to the receptor within ER-rich tumor cells, are both cytotoxic in vitro. Whereas the mechanisms and subcellular changes that accompany the cytotoxicity from [125I]deoxyuridine are well documented in the form of aberrations and breaks in the cellular DNA, the effects at the subcellular level causing the cytotoxicity of the sex steroid receptor ligand [125I]E have not been characterized and are the focus of our study. We found that in a standard colony-forming assay the addition of [125I]E to the cultures decreased the survival rate of ER-positive MCF-7 cells in a dose-dependent manner. The decreased survival rate was prevented by the addition of competing excess radioinert ER ligand (diethylstilbestrol); [125I]E did not reduce survival in ER-negative MCF-7 cells. The [125I]E-induced and ER-mediated cytotoxicity was accompanied by aberrations in the DNA components of the nuclei of the cells. These included chromatid and chromosome breaks, gaps, and tri-radial chromosome formation. Our findings add plausibility and credence to the notion that the cytotoxicity imparted by Auger-electron-emitting radioligands for sex steroid receptors is in part attributable to radiodecay that causes double-stranded breakage of DNA.

Detection of the HER-2/neu proto-oncogene protein p185erbB2 by a novel monoclonal antibody (MAB-145ww) in breast cancer membranes from oestrogen and progesterone receptor assays

Amplification of the proto-oncogene HER-2/neu and/or overexpression of the transmembrane protein p185erbB2 that it encodes occur in approximately 30% of human breast and gynaecological cancers seen clinically and are strongly associated with an unfavourable outcome. We report on the use of a new monoclonal antibody (Mab-145ww) together with immunoblotting for detection of p185erbB2 in membranes that remain after routine processing of breast cancer tissue for steroid receptor assays. Human breast cancer cell lines SKBR3 and MCF-7 were used as high and low controls, respectively, for p185erbB2 expression. Mab-145ww was detected p185erbB2 in more than half of the breast cancer specimens; the expression was intense in SKBR3 cells, but only faint in MCF-7 cells. These results demonstrate that routine processing of cancer tissue for steroid receptor status can include providing a preparation with which to assess p185erbB2 expression and, thus, can provide information potentially useful for the clinical management of individual cancer patients.

Correlation of cervicovaginal fluid volume with serum estradiol levels and total follicular volume during human gonadotropin stimulation

During the normal menstrual cycle the volume of cervicovaginal fluid (CVF), as determined by the patient at home using a simple volumetric aspirating pipette, increases significantly over several days prior to the luteinizing hormone (LH) surge and decreases characteristically shortly after ovulation. The present study was undertaken to test the hypothesis that self-determined measurements of CVF volume would correlate positively with serum estradiol (E2) levels and with total follicular volume (TFV) in cycles stimulated with exogenous gonadotropins. Consequently, 20 infertility patients, undergoing human menopausal gonadotropin (hMG)-stimulated cycles, were asked to measure daily CVF. Routine serum E2 determinations and vaginal follicular ultrasound studies were performed up to and including the day of human chorionic gonadotropin (hCG) administration (designated day 0). The mean daily CVF volume (+/- SD) increased from 0.1 +/- 0.01 ml on day -6 to 0.7 +/- 0.40 ml on day -1 and then decreased to 0.6 +/- 0.40 ml on day 0. On day 0, 7 of 20 cycles (35%) demonstrated a decrease in CVF, which ranged from 0.1 to 1.0 ml (mean, 0.42 ml). The mean daily CVF correlated positively (correlation coefficient = r) with the mean daily serum E2 (r = 0.89) and with the mean daily TFV (r = 0.88). The mean daily correlation of TFV for E2 was r = 0.98. The correlation between CVF and E2 of individuals ranged from r = 0.38 to r = 0.99 and the correlation between CVF and TFV ranged from r = 0.12 to r = 1.0, while the individual correlations of E2 to TFV ranged from r = 0.60 to r = 0.99.(ABSTRACT TRUNCATED AT 250 WORDS)

Intracellular actions of steroid hormones and their therapeutic value, including the potential of radiohalosteroids against ovarian cancer

The biological activities of steroid hormones are effected via intracellular receptors. The receptors are part of a ligand-activated family of transcription regulator proteins that are critical for steroid-regulated cell differentiation. With recombinant cDNA technology, yeast and cultured animal cells can be made to express mammalian cDNA steroid receptors from cDNA clones that contain deletions and substitutions. Among the leading problems addressed in these models is the characterization of sequences that promote association or interaction with other transcription regulating molecules, including oncogene products. Recently it has been found that heat shock proteins may serve not only to stabilize the receptor proteins but also to precondition the activation imparted by ligand binding. Aberrant receptor proteins can be found in ovarian cancer. Whether aberrant receptor proteins are associated with transformation in general or with a variable clinical response to steroidal or anti-steroidal therapy is not known. Even after chemotherapy, steroid receptors are expressed in the metastases of ovarian cancers seen clinically, and they may have potential uses for localization and treatment of receptor-rich cancers. Radioligand pharmaceuticals appropriate for imaging or for site-directed radiocytotoxicity can be sequestered to the nuclei of receptor-rich cancers. Initial clinical imaging and therapy trials with such pharmaceuticals have been approved and begun. In the use of halogenated estrogen radiopharmaceuticals, liver metabolism and enterohepatic recirculation are important considerations. Ascites prolongs retention of a radiohalogenated estrogen in the abdominal cavity. Distant metastases have been localized with [123I]-estrogen in breast cancer patients in pre-operative procedures. Receptor-mediated cytotoxicity occurs when estrogen receptor radioligand pharmaceuticals that are Auger electron emitters are used in vitro.

[Regulation of sterol carrier protein-2 in human luteal cells by LH and LH-RH]

Conversion of cholesterol to pregnenolone is the most important and, at the same time, the rate-limiting step of steroidogenesis. Sterol carrier protein-2 (SCP2) or nonspecific lipid transfer protein (nsL-TP) is an intracellular protein, which plays an important role in the pre- and transmitochondrial transport of cholesterol and for the mitochondrial synthesis of pregnenolone. Synthesis of pregnenolone in rat Leydig cells can be increased by LH and LH-RH; however, only LH leads to characteristic changes in intracellular concentrations of SCP2. This means that synthesis of pregnenolone is regulated in two different ways. In this study we aimed to find out whether such a 'second way' of steroidogenesis is also demonstrable for the human corpus luteum (i.e. human luteal cells). Human luteal cells were collected during follicle punctures and were cultured as described previously. We demonstrate that (human) LH/hCG are able to enhance pregnenolone synthesis; this process is accompagnied by typical changes of SCP2 and an increase in activity of 7-dehydrocholesterol reductase, which is a marker enzyme for SCP2. LH-RH was shown to exert no effect. Thus, we conclude that a second way of steroidogenesis (i.e. synthesis of pregnenolone) cannot be proved for the human corpus luteum.

Prolonged clearance of intraperitoneal 16 alpha-[125I]iodo-17 beta-estradiol in presence of ascites

Radioestrogens have potential as adjunct therapeutic agents against ovarian carcinoma, because selected radionuclides can deposit lethal doses of radiation to tumor cells and many ovarian carcinomas and their metastases express estrogen receptors. Because intraperitoneal administration is a possible approach, we investigated absorption from the peritoneal cavity of a radioiodoestradiol after intraperitoneal application in rats with and without ovarian tumors and ascites and compared the distribution of the radioactivity with that obtained after intravenous injection. In the absence of ascites, 70% of the intraperitoneal dose was cleared into the intestine within 2 hours after injection, indicating fast absorption from the peritoneal cavity. In the presence of ascites, clearance of intraperitoneal radioiodoestradiol was considerably slower; at 2 hours after injection, 50% of the injected dose remained in the ascites, mostly as radioiodoestradiol. Uptake of radioactivity in estrogen receptor-rich tissues, e.g., uterus, after intraperitoneal injection was high (about 20:1 over blood), regardless of the presence of ascites, but moderately lower than that observed after intravenous injection of radioiodoestradiol.

Rapid liver metabolism, urinary and biliary excretion, and enterohepatic circulation of 16 alpha-radioiodo-17 beta-estradiol

The radiohalogenated estrogen 16 alpha-[123I]iodo-17 beta-estradiol ([123I]E2) is emerging as a diagnostic tool for imaging of ER-rich malignant tumors, with potential application for site-directed radiotherapy. Clinical use requires an accurate accounting for the biodistribution of the radioactivity, including an assessment of its enterohepatic circulation. We investigated the metabolism and circulation of [125I]E2 in the enterohepatic system in swine, a pharmacokinetic model that resembles humans. With indicator dilution methods, we found that, after its injection into the portal vein, more than 99% of [125I]E2 was cleared from the blood by the liver during the first pass. Water-soluble metabolites were then partly released into the blood and partly excreted into bile. After injection of [125I]E2 into the external jugular vein, one-third of the radioactivity was excreted in bile and two-thirds in the urine. More than 90% of the radioactivity in urine and bile was that of [125I]E2-glucuronide or [125I]E2-sulfate; only a very small fraction of the excreted radioactivity was from free 125I. Radioactivity in bile collected from one swine after i.v. injection of [125I]E2, and then infused into the proximal duodenum of a second swine, was almost totally absorbed during passage through the intestine at 5-7 hr after infusion. The reabsorbed radioactivity was cleared in the urine.

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).

Biodistribution, with high uptake by the reproductive tract, of an intraperitoneally infused radiohalogenated steroidal estrogen-receptor ligand

We infused [123I]16 alpha-(123I)-iodo-estradiol ([123I]E2) intraperitoneally (i.p.) into swine to study its biodistribution and to explore the i.p. use of radiohalogenated steroid estrogen-receptor (ER) ligands as a potential option for diagnosing and treating intra-abdominal, retroperitoneal, and distant sites of advanced ER-rich malignancies. Fifty to 80% of the radiolabel was absorbed from the peritoneal cavity within 30 minutes, and 30 to 50% of the infused radiolabel was excreted in the urine within 2 hr. The rate of biliary clearance was maximal within 25 minutes. At 3 hr, the ER-rich reproductive tract had greater than 63 times the concentration of radiolabel in blood; the former was blocked by non-labeled competitors for ER. Uptake by non-ER-rich tissues, compared to blood, ranged from 0.7:1 (heart and lungs) to 16:1 (spleen); the omentum, however, exhibited a concentration as high as 64:1, which was not blocked by non-labeled ER ligands. Uptake by ER-rich target tissue remained high when charcoal was used to prevent reabsorption of radiolabel from the digestive tract after its biliary excretion, and when the products of biliary excretion were removed by catheterization of the common bile duct. Neither charcoal nor exteriorization of bile appeared to affect urinary clearance of the radiolabel over the time course of the experiments. Taken together with the recent development of syntheses that yield radiohalogenated sex steroid receptor ligands of high specific activity, our findings are encouraging for the potential application of radiolabeled ligands as i.p. administered pharmaceuticals. The advantage of the i.p. route is that it provides direct uptake of the pharmaceutical by free-floating clusters and individual cancer cells in ascitic fluid, as well as delivery via the circulation to vascularized intra- and/or extraperitoneal metastases.

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.

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.

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.

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.