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Adoptive transfer of murine chronic-relapsing autoimmune encephalomyelitis. Analysis of basic protein-reactive cells in lymphoid organs and nervous system of donor and recipient animals.

Frequency analysis of myelin basic protein (MBP)-reactive lymphocytes was performed in the chronic relapsing murine experimental allergic encephalomyelitis (EAE) model induced by the adoptive transfer of myelin basic protein (MBP)-primed lymphocytes to naive recipients. During the first attack, MBP-reactive cell frequencies were: 1/41,700 in spleen, 1/328,000 in lymph nodes, 1/64,500 in the peripheral blood. After recovery from a second attack, the frequencies were: 1/11,000 in spleen, 1/46,000 in lymph node, and 1/195,000 in the blood. In addition, lymph node cells obtained from animals following a second attack had increased encephalitogenic properties. CNS-derived lymphocytes analyzed during the first attack were 50% Lyt 1.2+ and 16% Lyt 2.2+. After recovery from the second attack, phenotypes were 20% Lyt 1.2+ and 49% Lyt 2.2+. There were only minimal responses to MBP in CNS-derived lymphocytes. Susceptibility to adoptively transferred EAE was in general predicted by whether a proliferative response to MBP occurred following immunization and was not solely H-2 linked. These studies demonstrate an accumulation of autoreactive cells in the spleen and lymph nodes and a shift of the phenotype of cells in the target organ as EAE becomes chronic and suggest there are dynamic immunologic processes, both in the peripheral immune system and target organ associated with relapsing EAE.

Animals↗

Macrophages sequentially change their functional phenotype in response to changes in microenvironmental influences.

Recent studies have described the development of distinct functional subsets of macrophages in association with cancer, autoimmune disease, and chronic infections. Based on the ability of Th1 vs Th2 cytokines to promote opposing activities in macrophages, it has been proposed that macrophages develop into either type 1 inflammatory or type 2 anti-inflammatory subsets. As an alternative to the concept of subset development, we propose that macrophages, in response to changes in their tissue environment, can reversibly and progressively change the pattern of functions that they express. As demonstrated herein, macrophages can reversibly shift their functional phenotype through a multitude of patterns in response to changes in cytokine environment. Macrophages display distinct functional patterns after treatment with IFN-gamma, IL-12, IL-4, or IL-10 and additional functional patterns are displayed depending on whether the cytokine is present alone or with other cytokines and whether the cytokines are added before or concomitantly with the activating stimulus (LPS). Sequential treatment of macrophages with multiple cytokines results in a progression through multiple functional phenotypes. This ability to adapt to changing cytokine environments has significant in vivo relevance, as evidenced by the demonstration that macrophage functional phenotypes established in vivo in aged or tumor-bearing mice can be altered by changing their microenvironment. A concept of functional adaptivity is proposed that has important implications for therapeutic targeting of macrophages in chronic diseases that result in the dominance of particular functional phenotypes of macrophages that play a significant role in disease pathology.

Animals↗

Sensitivity to inhibition by beta-chemokines correlates with biological phenotypes of primary HIV-1 isolates.

Primary HIV-1 isolates were evaluated for their sensitivity to inhibition by beta-chemokines RANTES (regulated upon activation, normal T-cell expressed and secreted), macrophage inflammatory protein 1 alpha (MIP-1 alpha), and MIP-1 beta. Virus isolates of both nonsyncytium-inducing (NSI) and syncytium-inducing (SI) biological phenotypes recovered from patients at various stages of HIV-1 infection were assessed, and the results indicated that only the isolates with the NSI phenotype were substantially inhibited by the beta-chemokines. More important to note, these data demonstrate that resistance to inhibition by beta-chemokines RANTES, MIP-1 alpha, and MIP-1 beta is not restricted to T cell line-adapted SI isolates but is also a consistent property among primary SI isolates. Analysis of isolates obtained sequentially from infected individuals in whom viruses shifted from NSI to SI phenotype during clinical progression exhibited a parallel loss of sensitivity to beta-chemokines. Loss of virus sensitivity to inhibition by beta-chemokines RANTES, MIP-1 alpha, and MIP-1 beta was furthermore associated with changes in the third variable (V3) region amino acid residues previously described to correlate with a shift of virus phenotype from NSI to SI. Of interest, an intermediate V3 genotype correlated with a partial inhibition by the beta-chemokines. In addition, we also identified viruses sensitive to RANTES, MIP-1 alpha, and MIP-1 beta of NSI phenotype that were isolated from individuals with AIDS manifestations, indicating that loss of sensitivity to beta-chemokine inhibition and shift in viral phenotype are not necessarily prerequisites for the pathogenesis of HIV-1 infection.

Acquired Immunodeficiency Syndrome↗

Beyond data and technology: the need for new thinking to enable the era of precision prevention.

BACKGROUND: Global flagship initiatives increasingly advocate for proactive health maintenance to alleviate the growing burden on reactive, disease-focused healthcare systems. Precision prevention is conceived as the targeted modulation of causal pathways across the disease continuum, from latent risk and pre-disease states to clinical manifestation, surpassing conventional public health prevention strategies that prioritise managing population-level risk factors. Traditional discovery and implementation models, however, remain poorly aligned with the pace and breadth of scientific and technological advances. This review outlines key barriers to scaling precision prevention and argues for the integration of conceptual, methodological, and policy perspectives into a single implementation‑oriented framework. MAIN: Individualised risk stratification lies at the core of precision prevention. Genomics serves as a stable substrate for lifetime susceptibility assessment, while meaningful prediction in multifactorial chronic disease requires additional risk monitoring using dynamic intermediate molecular markers and high-resolution exposomic data. Machine learning and other artificial intelligence (AI) methods are increasingly helpful tools for integrating large, heterogeneous and temporally structured real-world data to generate personalised predictions of health trajectories. Trustworthy AI-enabled risk prediction or decision-support systems are expected to provide transparency about model logic, assumptions and performance. In discovery, existing diagnostic classifications and conventional case-control designs can obscure mechanistic heterogeneity. Shifting toward precision phenotyping and biologically grounded disease redefinition could reveal a new layer of molecular understanding. Evidence generation strategies that reflect the temporal change of disease, including high‑risk enrichment, surrogate endpoints, and adaptive, trajectory-based monitoring, are particularly important for common conditions with prolonged latency periods (e.g., cancer, cardiovascular disease). Features often dismissed as "noise", such as stochastic molecular variation and minimal exposures, may in fact encode meaningful individual-level signals and thus merit investigation. CONCLUSION: To shift healthcare from reactive treatment toward proactive health maintenance requires coordinated action from stakeholders to reshape the pillars of discovery, reform outcome assessments and modernise implementation strategies.

Humans↗

P85gag-mos encoded by ts110 Moloney murine sarcoma virus: rapid at the restrictive temperature.

The stability of P85gag-mos, encoded by ts110 Moloney murine sarcoma virus, was studied. P85gag-mos was found to turn over more rapidly at 39 degrees C than 33 degrees C in two different cell lines. One of these is a non-producer cell clone (6m2) which appears only to express P85 at 33 degrees C. The other cell line (206-2IC) produces P85gag-mos at both 33 degrees C and 39 degrees C, although in lower amounts at the higher temperature. Both cell lines exhibit the normal morphological phenotype following a shift to the restrictive temperature. These data suggest that the presence of P85gag-mos alone is insufficient to cause transformation, and that some function(s) associated with the molecule may be heat-labile.

Animals↗

Direct correlation between a negative autoregulatory response element at the cap site of the herpes simplex virus type 1 IE175 (alpha 4) promoter and a specific binding site for the IE175 (ICP4) protein.

In transient-expression assays, the IE175 (alpha 4) promoter region of herpes simple virus is down-regulated after cotransfection with DNA encoding its own protein product (IE175 or ICP4). The inhibition by IE175 proved to be highly specific for its own promoter region and did not act on either the herpes simplex virus type 1 IE110 (alpha 0) or human cytomegalovirus major immediate-early promoters. Furthermore, the inhibition was still exhibited by IE175 effector plasmids driven by strong heterologous promoters and therefore must be a direct autoregulatory response that cannot be explained by promoter competition effects. In gel mobility retardation assays with infected-cell nuclear extracts, a prominent and specific DNA-protein complex was formed with DNA fragments containing sequences from -108 to +30 in the IE175 promoter region. This activity was not present in mock-infected samples. Even stronger binding occurred with a fragment containing sequences from -128 to +120 in the IE110 promoter, but this second locus was not associated with any detectable response phenotype in cotransfection assays. Supershift experiments with an anti-IE175 monoclonal antibody confirmed the presence of the IE175 protein in both DNA-protein complexes. In the IE175 promoter, specific binding correlated closely with the presence of an intact autoregulatory signal near the cap site as judged by the loss of both activities in a 3'-deleted promoter fragment lacking sequences from -7 to +30. Insertion of a cloned 30-mer synthetic oligonucleotide sequence from positions -8 to +18 in IE175 restored both IE175 binding activity and the down-regulation phenotype. Direct shift-up assays with a similar 30-base-pair (bp) oligonucleotide containing 21 bp from positions -75 to -55 of IE110 (which encompasses a consensus ATCGTC motif) also produced a specific DNA-protein complex containing the IE175 protein. This ATCGTC motif proved to be a necessary component of both the IE110 and IE175 binding sites, but was insufficient on its own for complex formation. Finally, deletion of 2 bp from positions -3 and -4 within the ATCGTC sequence in the IE175 cap site region abolished both binding activity and the IE175-dependent autoregulation phenotype.

Animals↗

Polyhomeotic: a gene of Drosophila melanogaster required for correct expression of segmental identity.

A new locus in Drosophila melanogaster that is required for the correct expression of segmental identity has been discovered. The new locus, termed polyhomeotic (ph), is X-linked and maps cytologically to bands 2D2-3. Homozygous ph flies have homeotic transformations similar to those of known dominant gain of function mutants in the Antennapedia and bithorax complexes (ANT-C, BX-C), and in addition show loss of the humerus. ph interacts with three other similar mutations: Polycomb (Pc), Polycomblike (Pcl), and extra sex comb (esc), and acts as a dominant enhancer of Pc. The expression of ph depends on the ANT-C and BX-C dosage. ph has no embryonic phenotype, but temperature shift studies on ph2 show that the ph+ product is required during embryogenesis and larval development. We propose that ph mutants in some way disrupt the normal expression of the ANT-C and BX-C, and, therefore, that ph+ is needed for maintenance of segmental identity.

Animals↗

Use of molecular techniques to distinguish between treatment failure and exogenous reinfection with Mycobacterium tuberculosis.

We investigated the means by which drug resistance emerges among drug-susceptible Mycobacterium tuberculosis strains during antituberculosis therapy. Patients who experienced failure of treatment for active pulmonary tuberculosis, who initially received diagnoses of infection with drug-susceptible M. tuberculosis, and who had had at least 3 isolates tested for drug susceptibility were selected from a 6-year period in the Estonian National Reference Laboratory archive. Eleven patients from whom 35 sequential isolates of M. tuberculosis had been obtained were recruited into the study. Their clinical data and treatment charts were analyzed and correlated with drug-susceptibility patterns and IS6110 restriction fragment-length polymorphism (RFLP) profiles. Six patients excreted isogenic drug-susceptible M. tuberculosis strains, whereas, in the other 5 patients, the isolated strain shifted from a susceptible to a resistant phenotype. In all cases, this shift correlated to a shift in RFLP pattern, which showed reinfection with a new strain. Exogenous reinfection with drug-resistant M. tuberculosis may be misinterpreted as the emergence of drug resistance if molecular testing techniques are not used.

Adult↗

Major age-related changes of mouse hematopoietic stem/progenitor cells.

To study age-related changes of mouse bone marrow (BM) cells and hematopoietic stem cells (HSCs), we isolated rhodamine-123(low) (Rh(low)) Thy1.1(low) Lin(-)Sca-1(+) (TLS) HSCs from the BM of old mice and compared their functional characteristics to cells of the same phenotype isolated from young mice. We observed impaired recovery of B lymphocytes and decreased self-renewal in recipients of old Rh(low) cells compared to young Rh(low) cells. Blockade of Rh efflux using verapamil improved lymphoid reconstitution by enriched HSCs, and isolation of aged HSCs based on efflux of a fluorescent multi-drug resistance (MDR) substrate (Bodipy-verapamil) resulted in enrichment of HSC activity equivalent to that obtained with Rh. These observations suggest a complex relationship between MDR activity and HSC function during aging. To address whether the difference between young and aged donors was intrinsic to the HSC compartment or was due to a shift in HSC phenotype, we co-transplanted normal BM derived from young or old donors and followed repopulation simultaneously in the same recipient animals. In a parallel experiment, we co-transplanted HSCs purified from old donors with BM derived from young donors. In both experiments, transplants were given to both young and old recipients. The results show a clear defect in B-cell engraftment from either BM or HSCs of old donors, irrespective of the age of the recipient. In contrast, myeloid engraftment was predominantly derived from BM or HSCs derived from aged donors, again irrespective of recipient age. These data suggest a stem cell basis for B-cell immuno-senescence and the increased incidence of myelocytic leukemia in elderly people.

Age Factors↗

Surface phenotypes of human hemopoietic progenitor cells defined by monoclonal antibodies.

A panel of ten monoclonal antibodies which react with antigens present on the surface of myeloid leukemic cells was used to investigate the distribution of these antigens on normal hemopoietic stem cells and progenitor cells at various stages of maturity. A population of immature cells, possibly stem cells, that are capable of regenerating CFU-GM in long-term marrow cultures reacts with four antibodies recognizing antigens abundantly expressed in leukemic cells, but does not react with antibodies against Ia-like molecules or against carbohydrate determinants specific for myeloid cells. Progenitor cells that form mixed colonies in semisolid medium (CFU-GEMM), early erythroid (BFU-E) and early myelomonocytic (type 1 CFU-GM) progenitors retain the antigens present on the hypothetical stem cell population and begin to express Ia-like antigens. As they differentiate, myeloid and erythroid progenitors undergo a series of quantitative and qualitative shifts in surface phenotype. They begin to express stage-related, lineage-specific antigens and cease expressing antigens common to early cells of different lineages. The identification of antigens present on very immature normal progenitor cells should be valuable in future studies aimed at the detailed characterization of this relatively little-known hemopoietic cell population.

Animals↗

Dietary cholesterol does not increase biomarkers for chronic disease in a pediatric population from northern Mexico.

BACKGROUND: An increased incidence of coronary artery disease (CAD) is prevalent in northern Mexico. Effects of specific dietary components on risk factors for CAD have not been evaluated in children. OBJECTIVE: The purpose was to evaluate the effects of dietary cholesterol provided by whole eggs on the lipoprotein profile, LDL size, and phenotype in children from this region. DESIGN: Children (29 girls and 25 boys aged 8-12 y) were randomly assigned to either 2 eggs/d (EGG period; 518 additional mg cholesterol) or the equivalent amount of egg whites (SUB period; 0 additional mg cholesterol) for 30 d. After a 3-wk washout period, the children were assigned to the alternate treatment. RESULTS: Subjects were classified as hyporesponders (no increase or </=0.05 mmol/L increase in plasma cholesterol for 100 mg additional cholesterol) or hyperresponders (>/=0.06 mmol/L increase). During the EGG period, the hyperresponders (n = 18) had an elevation in both LDL cholesterol (from 1.54 +/- 0.38 to 1.93 +/- 0.36 mmol/L) and HDL cholesterol (from 1.23 +/- 0.26 to 1.35 +/- 0.29 mmol/L) with no changes in LDL:HDL. In contrast, hyporesponders (n = 36) had no significant alterations in plasma LDL or HDL cholesterol. All subjects had an increase in LDL peak diameter during the EGG period (P < 0.01) and a decrease (P < 0.01) in the smaller LDL subfractions. In addition, 5 of the children having LDL phenotype B (15%) shifted from this high-risk pattern to pattern A after the EGG treatment. CONCLUSIONS: Intake of 2 eggs/d results in the maintenance of LDL:HDL and in the generation of a less atherogenic LDL in this population of Mexican children.

Analysis of Variance↗

Nitric oxide contributes to the development of a post-injury Th2 T-cell phenotype and immune dysfunction.

Severe injury induces immune dysfunction resulting in increased susceptibility to opportunistic infections. Previous studies from our laboratory have demonstrated that post-burn immunosuppression is mediated by nitric oxide (NO) due to the increased expression of macrophage inducible nitric oxide synthase (iNOS). In contrast, others suggest that injury causes a phenotypic imbalance in the regulation of Th1- and Th2 immune responses. It is unclear whether or not these apparently divergent mediators of immunosuppression are interrelated. To study this, C57BL/6 mice were subjected to major burn injury and splenocytes were isolated 7 days later and stimulated with antiCD3. Burn injury induced NO-mediated suppression of proliferative responses that was reversed in the presence of the NOS inhibitor L-monomethyl-L-arginine and subsequently mimicked by the addition of the NO donor, S-nitroso-N-acetyl-penicillamine (SNAP). SNAP also dose-dependently suppressed IFN-gamma and IL-2 (Th1), but not IL-4 and IL-10 (Th2) production. Delaying the addition of SNAP to the cultures by 24 h prevented the suppression of IFN-gamma production. The Th2 shift in immune phenotype was independent of cGMP and apoptosis. The addition of SNAP to cell cultures also induced apoptosis, attenuated mitochondrial oxidative metabolism and induced mitochondrial membrane depolarization. However, these detrimental cellular effects of NO were observed only at supra-physiologic concentrations (>250 microM). In conclusion, these findings support the concept that NO induces suppression of cell-mediated immune responses by selective action on Th1 T cells, thereby promoting a Th2 response.

Animals↗

Effects of 20-week intermittent cold-water-immersion on phenotype and myonuclei in single fibers of rat hindlimb muscles.

The effects of 20 weeks of intermittent cold-water-immersion on myosin heavy chain (MHC) expression,cross-sectional area (CSA), myonuclear number, and myonuclear domain size in isolated single fiber of soleus and extensor digitorum longus (EDL) muscles were studied in male Wistar rats. Cold exposure was accomplished by submerging the rats in shoulder-deep water, maintained at approximately 18 degrees C, for 1 hour/day, 5 days/week and for 20 weeks. Cold exposure resulted in a significant inhibition of body and soleus muscle weight gain. The percent type IIa MHC fibers of EDL muscle was increased, whereas that of type IIa + b MHC fibers was less in cold-exposed group than controls (p < 0.05). The mean CSA and myonuclear number in type I MHC fibers of soleus muscle in cold-exposed group were significantly less than controls. Myonuclear domain in type IIa fibers of EDL in the cold-exposed group was greater than controls (p < 0.05). It is suggested that prolonged cold exposure causes the fiber-type-specific adaptation in rat hindlimb muscles. It is further indicated that cold-exposure-related modulation of myonuclear number was closely related to reduction of fiber CSA, not the shift of fiber phenotype.

Animals↗

Enhanced yolk testosterone influences behavioral phenotype independent of sex in Japanese quail chicks Coturnix japonica.

Studies have demonstrated an effect of yolk testosterone levels on the physiology and behavior of nestling birds. In order to investigate this phenomenon experimentally in a precocial bird, we enhanced yolk testosterone, but within the physiological range, by injecting 50 ng testosterone in ethanol into Japanese quail Coturnix japonica eggs prior to incubation. The chicks hatching from these as well as from control eggs that had received the carrier-only or were left unmanipulated were subject to a number of behavioral tests from hatching to the age of 3 weeks. In addition, fecal samples were taken during a 90-min isolation period to determine a physiological response to a stressor. Experimental chicks performed a detour task faster and approached novel objects sooner than did the controls. Chicks from treated eggs took a longer time to start distress vocalizing and also produced less distress calls during open-field trials, took on average a larger number of trials for them to show tonic immobility and also excreted lower levels of corticosterone metabolites (BM) than did the controls. In response to a stressor, excreted BM was initially higher in the control chicks, as compared to the experimental birds. Induced behavioral effects were independent of sex with no sex treatment interactions found. In sum, experimentally enhanced testosterone levels in the eggs shifted individual behavioral phenotype towards "bold" or "proactive", irrespective of sex. We conclude that testosterone in the yolk influences the coping style of hatchlings and may be a potential means of maternal influence on offspring phenotype.

Androgens↗

Exercise-induced alterations in skeletal muscle myosin heavy chain phenotype: dose-response relationship.

This study investigated the effects of exercise training duration on the myosin heavy chain (MHC) isoform distribution in rat locomotor muscles. Female Sprague-Dawley rats (120 days old) were assigned to either a sedentary control group or to one of three endurance exercise training groups. Trained animals ran on a treadmill at approximately 75% maximal O2 uptake for 10 wk (4-5 days/wk) at one of three different exercise durations (30, 60, or 90 min/day). Training resulted in increases (P < 0.05) in citrate synthase activity in the soleus and extensor digitorum longus in both the 60 and 90 min/day duration groups and in the plantaris (Pla) in all three exercise groups. All durations of training resulted in a reduction (P < 0.05) in the percentage of MHCIIb and an increase (P < 0.05) in the percentage of MHCIIa in the Pla. The magnitude of change in the percentage of MHCIIb in the Pla increased as a function of the training duration. In the extensor digitorum longus, 90 min of daily exercise promoted a decrease (P < 0.05) in percentage of MHCIIb and increases (P < 0.05) in the percentages of MHCI, MHCIIa, and MHCIId/x. Finally, training durations >/=60 min resulted in an increase (P < 0.05) in the percentage of MHCI and a concomitant decrease (P < 0.05) in the percentage of MHCIIa in the soleus. These results demonstrate that increasing the training duration elevates the magnitude of the fast-to-slow shift in MHC phenotype in rat hindlimb muscles.

Animals↗

Diverse origins of waxy foxtail millet crops in East and Southeast Asia mediated by multiple transposable element insertions.

The naturally occurring waxy and low-amylose variants of foxtail millet and other cereals, like rice and barley, originated in East and Southeast Asia under human selection for sticky foods. Mutations in the GBSS1 gene for granule-bound starch synthase 1 are known to be associated with these traits. We have analyzed the gene in foxtail millet, and found that, in this species, these traits were originated by multiple independent insertions of transposable elements and by subsequent secondary insertions into these elements or deletion of parts of the elements. The structural analysis of transposable elements inserted in the GBSS1 gene revealed that the non-waxy was converted to the low-amylose phenotype once, while shifts from non-waxy to waxy occurred three times, from low amylose to waxy once and from waxy to low amylose once. The present results, and the geographical distribution of different waxy molecular types, strongly suggest that these types originated independently and were dispersed into their current distribution areas. The patterns of GBSS1 variation revealed here suggest that foxtail millet may serve as a key to solving the mystery of the origin of waxy-type cereals in Asia. The GBSS1 gene in foxtail millet provides a new example of the evolution of a gene involved in the processes of domestication and its post-domestication fate under the influence of human selection.

Asia, Southeastern↗

The influence of environmental and genetic factors on CYP2D6, CYP1A2 and UDP-glucuronosyltransferases in man using sparteine, caffeine, and paracetamol as probes.

The impact of gender, use of oral contraceptive steroids (OCS), coffee consumption and of smoking on the metabolism of sparteine, caffeine, and paracetamol was studied in 194 randomly selected subjects (98 male and 95 female). Thirty-eight of the male volunteers were cigarette smokers, 40 of the female subjects were smokers and/or users of OCS. The metabolic ratio of sparteine oxidation (MRs) showed a trimodal distribution. 7.7% of the subjects had a MRs > 20 and thus were poor metabolizers (PMs). Within the extensive metabolizer (EM) subjects, a distinct subgroup accounting for 11% was observed with 20 > MRs > 1.2. Six of the 15 phenotypical PMs were heterozygous EMs by genotyping. This indicates the existence of one or several CYP2D6 mutations which cannot be identified by the currently employed genotyping methods. In each subgroup, i.e. smokers/OCS and non-smokers/non-OCS, the cumulative frequency distribution of the heterozygous (wt/B) phenotype caused a shift to higher MRs compared with the wild-type homozygotes (wt/wt). Thus, for the in vivo activity of CYP2D6, genetic determinants prevail over environmental factors. Smoking, use of oral contraceptive steroids, caffeine consumption, or gender had no influence on sparteine metabolism. The distribution of the paracetamol glucuronide/paracetamol metabolic ratio appeared to be unimodal although skewed. Glucuronidation capacity was clearly affected by gender, OCS use and smoking. It was higher in male than in female subjects. Male smokers had the highest, and female non-smokers/non-OCS users the lowest metabolic ratio. CYP1A2 activity, as determined by a caffeine metabolic ratio ((AFMU + 1X + 1U)/1, 7U), was multimodally distributed and was clearly increased in smokers. It was significantly correlated to paracetamol glucoronidation in male heavy smokers (r=0.85), suggesting an element of co-regulation of CYP1A2 and of paracetamol conjugating UDP-glucuronosyltransferase isozymes, including UGTI.6.

Acetaminophen↗

Expression of estrogen, progesterone and epidermal growth factor receptors in primary and metastatic breast cancer.

The prognostic value of epidermal growth factor receptor (EGFR) expression and its biological role in estrogen receptor-positive (ER+) and ER-negative (ER-) primary breast cancer is controversial. In this study, distributions of ER, progesterone receptor and EGFR have been established using immunohistochemistry in both primary breast tumors and their matched axillary lymph node metastases of 26 patients or their matched distant metastases of 2 patients. In addition, 5 patients with bilateral breast cancer were studied. ER+ tumor cells were detected in 22 (69%) and EGFR+ tumor cells were detected in 11 (34%) primary breast carcinomas. Expression of ER and EGFR was inverse regarding the individual tumor cells in both primary tumors and metastases. Relationship of EGFR expression with poorly differentiated and large breast tumors was observed. Furthermore, primary tumors with a predominant lobular component were ER+ and, with one exception, EGFR-. Invasive ductal carcinomas were more frequently EGFR+. No apparent differences in receptor expression were observed between primary tumors and lymph node metastases or chronously or metachronously occurring bilateral breast cancers. Only one ER+ primary tumor showed a switch to EGFR expression in the involved lymph node. Our study shows that a shift in receptor phenotype between primary tumors and lymph node metastases is a rare event and, thus, additional analyses of involved lymph nodes will not likely serve as a better predictor for response to anti-estrogen therapy. We conclude that expression of EGFR is not a prerequisite for development of metastases.

Adult↗