Tricuspid annular plane systolic excursion for the evaluation of right ventricular function in functional cardiac CT compared to MRI.

AIM: To compare ejection fraction estimated by tricuspid annular plane systolic excursion (TAPSE) using cardiac computed tomography (CT) and cardiac magnetic resonance imaging (MRI) to the non-invasive reference standard, volumetric quantification of right ventricular ejection fraction (RVEF) by cardiac magnetic resonance imaging (MRI). MATERIALS AND METHODS: Thirty-one patients, who had undergone functional cardiac CT angiogram and cardiac MRI within 12 months, were evaluated retrospectively. Right ventricular (RV) volumes were processed using automated cardiac analysis software for CT, and manually processed by Simpson's method for MRI. MR-TAPSE was defined as the difference in length between two separate reference lines drawn at end diastole and end systole from the lateral tricuspid annulus to the right ventricular apex measured on four-chamber CINE images. CT-TAPSE was determined in an analogous manner on four-chamber reformatted images. RESULTS: MR-TAPSE correlated moderately with MR-RVEF, (r=0.57, p<0.001). CT-TAPSE was found to correlate moderately well with MR-RVEF (r=0.58, p<0.001) and CT-RVEF (r=0.63, p<0.001). Bland-Altman analysis repeated with various multiplication factors for CT-TAPSE and MR-RVEF, determined a multiplication factor of 2.7 resulted in the lowest bias (0.74%). CONCLUSION: CT-TAPSE is an easily obtainable parameter of RV function and is correlated with CT-RVEF and MR-RVEF. It can function as a quick check to rapidly validate CT right volumetry and estimate MR-RVEF.

Aspects of transition cow metabolomics-Part I: Effects of a metaphylactic butaphosphan and cyanocobalamin treatment on the metabolome in liver, blood, and urine in cows with different liver metabotypes.

Dairy cows in modern production systems are at risk to develop metabolic disorders during the transition period. Reasons for individual differences in susceptibility, as well as the underlying pathomechanisms, are still only partially understood. The development of metaphylactic treatment protocols is needed. In this context, an on-farm prospective 3-fold blinded randomized study involving 80 German Holstein cows was performed throughout 1 yr. The trial involved a thorough recording of the production and clinical traits, clinical chemistry, and liver biopsies and blood and urine sampling at d 14 (mean: 12 d, range: 1-26 d) antepartum (AP), and d 7 (7, 4-13) and 28 (28, 23-34) postpartum (PP) for metabolomics analyses. Two groups received a treatment with butaphosphan and cyanocobalamin (BCC) at either the dosage recommended by the manufacturer or the double dosage (5 or 10 mL/100 kg of body weight 10% butaphosphan and 0.005% cyanocobalamin (Catosal, Bayer Animal Health), n = 20 in each group, parity: 4.2 ± 2.0 and 3.4 ± 1.3, respectively (mean ± SD)] and one group a placebo treatment (NaCl 0.9%, n = 40, parity: 4.0 ± 1.9). The animals were treated at 6 time points (7, 6, and 5 d AP, and 1, 2, and 3 d PP) via intravenous injection. Mass spectroscopy-based targeted metabolomics analysis of blood plasma and liver samples were performed using the AbsoluteIDQ p180 kit (Biocrates Life Sciences), whereas the urine samples were analyzed by nuclear magnetic resonance spectroscopy. Statistical analysis was performed using multivariate [partial least squares discriminant analysis (PLS-DA)] and univariate methods (linear mixed model). Multivariate data analysis (PLS-DA plots) of the liver metabolome revealed 3 different metabotypes (A = medium, B = minor, C = large alterations in liver metabolome profile between AP and PP status). Metabotype B animals were characterized by higher PP lipomobilization (stronger PP body condition decrease and higher blood bilirubin, fatty acids, gamma-glutamyltransferase, and triglyceride levels) and a higher occurrence of transition cow diseases, compared with the animals in metabotype C. Analysis of the feeding data showed that the period of metabotype B animals (calving in a distinct time frame) was characterized by a decreased grass silage quality. The PP liver metabolome of the metabotype C animals was characterized by higher concentrations of AA, acylcarnitines, lysoPC and sphingomyelins compared with metabotype B. For the metaphylactic treatment with BCC a dose-dependent effect was confirmed, differing between the metabotypes. In all matrices and metabotypes at various time points significant treatment effects were observed, with different profiles in clinical chemistry and as well in metabolomics data. The most clear-cut treatment effect was observed in metabotype B in the liver at 7 d PP, characterized by an increase in several acylcarnitines and phosphatidylcholines, indicating a more efficient influx and oxidation of fatty acids in mitochondria and thereby an increase in energy supply and more efficient triglyceride export in the liver. The results from the liver metabolomics analysis support the application of an indication-based metaphylactic treatment with BCC.

Aspects of transition cow metabolomics-Part III: Alterations in the metabolome of liver and blood throughout the transition period in cows with different liver metabotypes.

The liver plays a central role in the postpartum (PP) energy metabolism of the transition dairy cow; however, studies describing the liver metabolome during this period were lacking. The aim of the presented study was therefore to compare the alterations in the liver and blood metabolome of transition dairy cows. For this purpose, an on-farm trial with 80 German Holstein cows (mean lactation number: 3.9; range: 2-9) was performed, with thorough documentation of clinical traits and clinical chemistry, as well as production data. Liver biopsies and blood samples were collected at d 14 (mean: 12 d, range: 1-26 d) antepartum (AP), d 7 (7, 4-13) and 28 (28, 23-34; mean, earliest-latest) PP for targeted mass spectroscopy-based metabolomics analysis using the AbsoluteIDQ p180 kit (Biocrates Life Sciences). Statistical analysis was performed using multivariate (partial least squares discriminant analysis) as well as univariate methods (linear mixed model). Multivariate data analysis of the liver metabolome revealed 3 different metabotypes (A = medium, B = minor, C = large alterations in the liver metabolome profile between AP and PP). In metabotype C, an increase of almost all acylcarnitines, lysophosphatidylcholines (lysoPC), sphingomyelins, and some phosphatidylcholines (PC, mainly at 7 d PP) was observed after calving. In contrast to metabotype C, the clinical data of the metabotype B animals indicated a higher PP lipomobilization and occurrence of transition cow diseases. The liver metabolome profile of these animals most likely mirrors a failure of adaptation to the PP state. This strong occurrence of metabotypes was much less pronounced in the blood metabolome. Additionally, differences in metabolic patterns were observed across the transition period when comparing liver and blood matrices (e.g., in different biogenic amines, acylcarnitines and sphingolipids). In summary, the blood samples at 7 d PP showed lower acylcarnitines and PC, with minor alterations and a heterogeneous pattern in AA, biogenic amines, and sphingomyelins compared with 14 d AP. In contrast to 7 d PP, the blood samples at 28 PP revealed an increase in several AA, lysoPC, PC, and sphingomyelins in comparison to the AP state, irrespective of the metabotype. In the liver biopsies metabotype B differed from metabotype C animals ante partum by following metabolites: higher α aminoadipic acid, lower AA, serotonin, taurine, and symmetric dimethylarginine levels, lower or higher concentrations of certain acylcarnitines (higher: C2, C3, C5, C4:1; lower: C12:1, C14:1-OH, C16:2), and lower lysoPC (a C16:0, C18:0, C20:3, C20:4) and hexose levels. In blood samples, fewer differences were observed, with lower serotonin, acylcarnitine C16:2, lysoPC (a C16:0, C17:0, C18:0 and C18:1), PC aa C38:0, and PC ae C42:2. The results show that the use of only the blood metabolome to assess liver metabolism may be hampered by the fact that blood profiles are influenced by the metabolism of many organs, and metabolomics analysis from liver biopsies is a more suitable method to identify distinct metabotypes. Future studies should investigate the stability and reproducibility of the metabotype and phenotypes observed, and the possible predictive value of the metabolites already differing AP between metabotype B and C.

Demonstration of Einstein-Podolsky-Rosen Steering Using Single-Photon Path Entanglement and Displacement-Based Detection.

We demonstrate the violation of an Einstein-Podolsky-Rosen steering inequality developed for single-photon path entanglement with displacement-based detection. We use a high-rate source of heralded single-photon path-entangled states, combined with high-efficiency superconducting-based detectors, in a scheme that is free of any postselection and thus immune to the detection loophole. This result conclusively demonstrates single-photon entanglement in a one-sided device-independent scenario, and opens the way towards implementations of device-independent quantum technologies within the paradigm of path entanglement.

Progesterone receptor isoform analysis by quantitative real-time polymerase chain reaction in formalin-fixed, paraffin-embedded canine mammary dysplasias and tumors.

Cloning and sequencing of the progesterone receptor gene in dogs have revealed 2 isoforms, A and B, transcribed from a single gene. Distribution of isoforms A and B in canine mammary lesions has hitherto been investigated only by Western blot analysis. This study analyzed progesterone receptor and its isoforms in formalin-fixed, paraffin-embedded tissue samples from canine mammary lesions (4 dysplasias, 10 benign tumors, and 46 carcinomas) using 1-step SYBR Green quantitative real-time polymerase chain reaction (RT-qPCR). Progesterone receptor was expressed in 75% of dysplasias, all benign tumors, and 59% of carcinomas. Carcinomas, and particularly simple epithelial-type carcinomas, displayed the lowest levels of expression. A high rate of agreement was recorded between RT-qPCR and immunohistochemical labeling. Isoforms A and B were successfully amplified, with correlation coefficients of 0.99 and amplification efficiencies close to 2, and were expressed in all lesion types analyzed. Predominance of A over B expression was observed in carcinomas and complex adenomas. Low-grade tumors exhibited higher progesterone receptor messenger RNA (mRNA) levels, but no difference was observed in the expression of isoform A versus B. Analysis of progesterone receptor mRNA isoforms by RT-qPCR was successful in routinely formalin-fixed, paraffin-embedded tissue samples and enabled the distribution of isoforms A and B to be identified for the first time in dysplasias, benign tumors, and malignant tumors of the canine mammary gland. These findings will facilitate future research into the role of progesterone receptor isoforms in the progression of canine mammary tumors.

Detection-loophole-free test of quantum nonlocality, and applications.

We present a source of entangled photons that violates a Bell inequality free of the "fair-sampling" assumption, by over 7 standard deviations. This violation is the first reported experiment with photons to close the detection loophole, and we demonstrate enough "efficiency" overhead to eventually perform a fully loophole-free test of local realism. The entanglement quality is verified by maximally violating additional Bell tests, testing the upper limit of quantum correlations. Finally, we use the source to generate "device-independent" private quantum random numbers at rates over 4 orders of magnitude beyond previous experiments.

Plasma TIMP-1 levels and treatment outcome in patients treated with XELOX for metastatic colorectal cancer.

BACKGROUND: The aim was to evaluate the association between plasma tissue inhibitor of metalloproteinase-1 (TIMP-1) and serum carcinoembryonic antigen (CEA) levels and outcome in patients with metastatic colorectal cancer (mCRC) receiving XELOX (combination chemotherapy with capecitabine and oxaliplatin) as first-line treatment. PATIENTS AND METHODS: One hundred and twenty patients were included. Blood samples were collected before treatment and 3 weeks later before the next treatment cycle. Plasma TIMP-1 and serum CEA levels were correlated to treatment outcome. RESULTS: No significant associations between baseline TIMP-1 or CEA levels and best response to treatment or progression-free survival (PFS) could be demonstrated. In contrast, high baseline plasma TIMP-1 levels were associated with poor overall survival (OS), P = 0.008, hazard ratio (HR) = 1.80 [95% confidence interval (CI): 1.17-2.78]. Furthermore, increase in TIMP-1 levels from baseline to immediately before the second cycle of chemotherapy had a significant negative effect on survival (P = 0.03, HR = 1.30, 95% CI: 1.02-1.65) while a decrease in TIMP-1 was significantly associated with a higher objective response rate (P = 0.03). CONCLUSIONS: Both high baseline and subsequent increase in TIMP-1 levels were associated with shorter OS in patients with mCRC receiving XELOX as first-line treatment, whereas baseline TIMP-1 levels were not associated with response or PFS following XELOX treatment.

Absence of host plasminogen activator inhibitor 1 prevents cancer invasion and vascularization.

Acquisition of invasive/metastatic potential through protease expression is an essential event in tumor progression. High levels of components of the plasminogen activation system, including urokinase, but paradoxically also its inhibitor, plasminogen activator inhibitor 1 (PAI1), have been correlated with a poor prognosis for some cancers. We report here that deficient PAI1 expression in host mice prevented local invasion and tumor vascularization of transplanted malignant keratinocytes. When this PAI1 deficiency was circumvented by intravenous injection of a replication-defective adenoviral vector expressing human PAI1, invasion and associated angiogenesis were restored. This experimental evidence demonstrates that host-produced PAI is essential for cancer cell invasion and angiogenesis.

The plasminogen activator inhibitor PAI-1 controls in vivo tumor vascularization by interaction with proteases, not vitronectin. Implications for antiangiogenic strategies.

The plasminogen (Plg)/plasminogen activator (PA) system plays a key role in cancer progression, presumably via mediating extracellular matrix degradation and tumor cell migration. Consequently, urokinase-type PA (uPA)/plasmin antagonists are currently being developed for suppression of tumor growth and angiogenesis. Paradoxically, however, high levels of PA inhibitor 1 (PAI-1) are predictive of a poor prognosis for survival of patients with cancer. We demonstrated previously that PAI-1 promoted tumor angiogenesis, but by an unresolved mechanism. We anticipated that PAI-1 facilitated endothelial cell migration via its known interaction with vitronectin (VN) and integrins. However, using adenoviral gene transfer of PAI-1 mutants, we observed that PAI-1 promoted tumor angiogenesis, not by interacting with VN, but rather by inhibiting proteolytic activity, suggesting that excessive plasmin proteolysis prevents assembly of tumor vessels. Single deficiency of uPA, tissue-type PA (tPA), uPA receptor, or VN, as well as combined deficiencies of uPA and tPA did not impair tumor angiogenesis, whereas lack of Plg reduced it. Overall, these data indicate that plasmin proteolysis, even though essential, must be tightly controlled during tumor angiogenesis, probably to allow vessel stabilization and maturation. These data provide insights into the clinical paradox whereby PAI-1 promotes tumor progression and warrant against the uncontrolled use of uPA/plasmin antagonists as tumor angiogenesis inhibitors.

Changes in plasma TIMP-1 levels after resection for primary colorectal cancer.

BACKGROUND: Increased plasma levels of tissue inhibitor of metalloproteinases (TIMP-1) are associated with poor outcome in colorectal cancer (CRC), however postoperative changes in plasma TIMP-1 levels after resections for CRC have not been thoroughly evaluated. MATERIALS AND METHODS: Plasma samples were collected from 45 patients with primary CRC, preoperatively, 2 hours after surgery, and at days 1, 2, 7, 28, 45, 60, 75 and 90 after surgery. TIMP-1 and CEA levels were determined using the ARCHITECT Immunoanalyzer. RESULTS: Postoperatively, the mean (geometric) TIMP-1 level increased and had a maximum level at day 1 (p < 0.0001). The mean TIMP-1 level then declined to a level at day 90 similar to the mean preoperative level. CONCLUSION: A mean decline in plasma TIMP-1 levels was not observed within 90 days. However, individual significant reductions of plasma TIMP-1 levels did occur within 28-60 days postoperatively.

Assessment of the biological variation of plasma tissue inhibitor of metalloproteinases-1.

BACKGROUND: Tissue inhibitor of metalloproteinases-1 (TIMP-1) measurements in plasma may be useful for the early detection and prognosis of colorectal cancer (CRC). Data on analytical performance and normal intra- and interindividual biological variation are required in order to interpret the utility of TIMP-1 in CRC. The aim of this study was to establish the biological and analytical variation of plasma TIMP-1 in volunteers. MATERIAL AND METHODS: Three separate studies were undertaken. 1: Plasma was collected from 23 volunteers 6 times within a 3-week period, first in September 2004 (round [R] 1), then repeated in May 2005 (R2) and May 2006 (R3) in the same group of individuals. TIMP-1 levels were determined by the MAC15 ELISA assay and with the Abbott ARCHITECT i2000 Immunoanalyzer. 2: Circadian variation was evaluated in plasma collected 7 times within a 24-hour period (n=16). 3: Effects of physical exercise were evaluated in plasma collected before and after bicycling (n=14). In studies 2 and 3 TIMP-1 levels were determined with the MAC15 ELISA assay only. RESULTS: A significant correlation between TIMP-1 MAC15 and ARCHITECT i2000 was shown (rs=0.78, p<0.002), with consistently higher levels being detected by the ARCHITECT i2000. Median levels of TIMP-1 (ARCHITECT) at 8 a.m. in each round were 74.9 ng/mL (range 65.7-89.9) (R1), 87.3 ng/mL (range 72.7-127.9) (R2), and 81.9 ng/mL (range 66.8-113.6) (R3). The within-subject variation was 10.7%, the variation between rounds was 7.4%, and the intraclass correlation was 46.2%. Comparison between the 3 rounds and time of collection showed that TIMP-1 values decreased by 11% after storage for more than 16 months (p=0.0002). A systematic circadian variation in plasma TIMP-1 levels was not observed (p=0.17). No significant variation of plasma TIMP-1 was found in relation to physical exercise (p=0.92 [global test]). CONCLUSION: Levels of plasma TIMP-1 in volunteers show limited circadian, day-to-day, week-to-week and season-to-season variation. In addition, physical exercise has no impact on plasma TIMP-1 levels. Possible storage-dependent decreases in plasma TIMP-1 levels warrant further investigation.

Investigation of tissue inhibitor of metalloproteinases 1 in plasma from colorectal cancer patients and blood donors by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry.

Early detection of colorectal cancer (CRC) improves patient survival. Plasma tissue inhibitor of metalloproteinases 1 (TIMP-1) measurements by enzyme-linked immunosorbent assay (ELISA) have been suggested as a new method for the early detection of CRC. To further investigate the nature of TIMP-1 in plasma, surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI TOF MS) was used. TIMP-1 measurements of plasma from 16 healthy donors and 14 CRC patients were performed using TIMP-1 monoclonal antibody in SELDI TOF MS and ELISA. SELDI TOF MS applying an antibody to TIMP-1 revealed that human plasma TIMP-1 has a mass of 25.1 kDa and exhibits several isoforms. Both methods showed increased plasma TIMP-1 values for cancer patients as compared to healthy individuals. The p values for the separation of the groups were 0.0019 for ELISA and <0.0001 for SELDI TOF MS. CRC did not fundamentally affect the appearance of TIMP-1 as evaluated by SELDI TOF MS.

Mendelian analysis of a metastasis-prone substrain of BALB/c nude mice using a subcutaneously inoculated human tumour.

Most nude mice do not allow the formation of metastases after heterotransplantation of human malignant tumours. Here we describe a substrain of BALB/c nude mice (BALB/c/AnNCr) that reproducibly allows some human cancers to metastasize. By Mendelian analysis of hybrids between this substrain and C57BL/6J +/+ mice we found that the ability to allow a human tumour (MDA-MB-435 BAG) to express its metastatic phenotype is determined by a recessively inheritable trait in the mouse host. We are presently working to identify the genetics responsible for development of metastases. The study also includes immunohistochemical and electron microscopic analysis of the test tumour, originally assumed to be a human mammary carcinoma, but shown to possess characteristics of a malignant melanoma (1). The ultimate aim of our ongoing study is to establish a substrain of nude mice that will allow metastasis in all recipients.

Levels of tissue inhibitor of metalloproteinases 1 in plasma and urine from patients with bladder cancer.

AIM: To assess the potential use of plasma and urine levels of tissue inhibitor of metalloproteinases 1 (TIMP-1) in urothelial cancer. METHODS: TIMP-1 levels were determined in urine and plasma from healthy donors (n=26), patients with bacterial bladder infection (n=24), urothelial bladder adenoma (n=3) or adenocarcinoma (n=7). RESULTS: Free and total TIMP-1 in plasma were weakly but significantly correlated with age; urinary TIMP-1 was not. A strong correlation between free and total TIMP-1 in plasma was observed, with an average ratio of 0.85. No correlation between total TIMP-1 in urine and plasma was found (p=0.55). No significant differences in free or total TIMP-1 in plasma were found between healthy individuals, patients with cystitis or bladder cancer (p=0.4). Urinary TIMP-1 levels were significantly increased in patients with cystitis (p=0.001). No apparent differences in TIMP-1 levels were found in patients with bladder cancer at different stages. CONCLUSION: Our previous observation of a weak but significant correlation between plasma TIMP-1 and age was confirmed. Likewise, an association between free and total TIMP-1 in plasma with a ratio of 0.85 was established. No correlation between plasma and urine TIMP-1 was found. Measurement of TIMP-1 in plasma and/or urine is apparently not useful for the identification of bladder cancer.

Plasma urokinase receptor levels in patients with colorectal cancer: relationship to prognosis.

BACKGROUND: The proteolytic enzyme plasmin, which is generated from the precursor plasminogen by the action of urokinase plasminogen activator, is thought to play a role in tumor cell invasion and metastasis. Urokinase plasminogen activator receptor (uPAR) is functionally involved in the cell surface activation (i.e., cleavage) of plasminogen. Increased tumor tissue levels of uPAR are associated with poor prognosis in several types of cancer. This retrospective study was undertaken to test the relationship between preoperative plasma levels of soluble uPAR (suPAR) and survival in patients with colorectal cancer. METHODS: suPAR levels in preoperative plasma from 591 patients with colorectal cancer were determined by use of a kinetic enzyme-linked immunosorbent assay and analyzed with respect to associations with postoperative survival, Dukes' stage, age, and serum carcinoembryonic antigen level. Plasma suPAR measurements were log transformed for survival analysis, which employed the Kaplan-Meier method and the Cox proportional hazards model. All P values reported are two-sided. RESULTS: Univariate analysis, using the log-transformed suPAR concentrations, demonstrated that there was an increasing risk of mortality with increasing plasma suPAR level (P<.0001). An arbitrary cut point, the median for all patients (1.37 ng/mL), divided patients with Dukes' stage B, C, or D disease into statistically different prognostic groups. In multivariate Cox analysis including Dukes' stage, age, and carcinoembryonic antigen level, the suPAR concentration independently predicted survival (P<.0001). CONCLUSIONS: The preoperative plasma suPAR level independently predicted survival of patients with colorectal cancer. Further studies of plasma suPAR in patients with cancer are needed to evaluate the utility of plasma suPAR measurements and cut points in identifying high-risk patients among those with early stage disease.

Effect of estrogen withdrawal on energy-rich phosphates and prediction of estrogen dependence monitored by in vivo 31P magnetic resonance spectroscopy of four human breast cancer xenografts.

The effect of estrogen withdrawal on energy metabolism was studied in four human breast cancer xenografts: the estrogen-dependent MCF-7 and ZR75-1 and the estrogen-independent ZR75/LCC-3 and MDA-MB-231. The tumors were grown in ovariectomized nude mice with a s.c. implanted estrogen pellet. After Gompertzian growth was verified, the estrogen pellet was removed from half of the animals. In vivo 31P magnetic resonance spectroscopy of the tumors was performed 1 day before and on days 2, 6, and 14 after estrogen removal. Estrogen withdrawal induced a significant increase in the nucleoside triphosphate:Pi ratio in the two estrogen-dependent xenografts, whereas this ratio remained unchanged in the estrogen-independent tumors. In ZR75/LCC-3 tumors a slight decrease in nucleoside triphosphate:Pi was observed following onset of estrogen stimulation after initial growth without estrogen. Extracts of freeze-clamped tumors prepared 14 days after estrogen removal were analyzed for ATP and phosphocreatine content. Our findings suggest a correlation between estrogen withdrawal and the steady-state concentrations of ATP, phosphocreatine, and Pi in human breast cancer xenografts. Discrimination analysis of the pretherapeutic spectra enabled us to identify the tumor line and the estrogen dependence of the tumors in 80-90% of all cases.

Acquisition of hormone-independent growth in MCF-7 cells is accompanied by increased expression of estrogen-regulated genes but without detectable DNA amplifications.

A hormone-independent but hormone-responsive subpopulation (MCF7/MIII) of the hormone-dependent MCF-7 human breast cancer cell line (R. Clarke et al., Proc. Natl. Acad. Sci. USA 86: 3649-3653, 1989) was further passaged in ovariectomized nude mice and re-established in vitro as the continuous cell line MCF7/LCC1. The lag time to the appearance of proliferating tumors in ovariectomized animals is significantly reduced in MCF7/LCC1 when compared with MCF7/MIII cells. In gel denaturation/renaturation analysis of tumor, genomic DNA does not reveal significant differences in the pattern of detectable DNA amplifications between parent MCF-7 cells and MCF7/LCC1 cells. In the absence of estrogen, steady-state levels of phosphoinositol turnover are similar in both MCF-7 and MCF7/LCC1 cells, but turnover is increased by estrogen only in MCF-7 cells. MCF7/MIII and MCF7/LCC1, but not MCF-7 cells, express a high baseline level of the estrogen-regulated pS2 mRNA. The baseline level of expression of progesterone receptor protein, but not mRNA, is higher in MCF7/LCC1 when compared with either MCF-7 or early passage MCF7/MIII cells. However, while the estrogen receptor is also an estrogen-regulated gene, MCF7/MIII and MCF7/LCC1 cells retain estrogen receptor levels equivalent to the parental MCF-7 cells. These data indicate that progression to hormone independence can occur without major gene amplifications or a high constitutive induction of phosphoinositide metabolism. Thus, DNA amplifications may be acquired during the early initiation and/or promotional events of carcinogenesis. Significantly, acquisition of a hormone-independent but responsive phenotype in human breast cancer is associated with perturbations in the expression of specific estrogen-regulated genes.

Receptor for urokinase is present in tumor-associated macrophages in ductal breast carcinoma.

Histological samples from 60 invasive ductal breast carcinomas were investigated for immunoreactivity for the receptor for urokinase-type plasminogen activator (uPAR) with the use of two monoclonal antibodies recognizing different epitopes. In 51 cases, uPAR immunoreactivity was observed, and in 49 of these specimens, a population of periductal tissue macrophages showed pronounced uPAR immunoreactivity in areas with infiltrating and intraductal carcinoma. In the 2 remaining positive specimens no stromal immunoreactivity was seen. The carcinoma cells were found to contain uPAR immunoreactivity in 8 of the 51 positive cases, including the two specimens that did not show stromal immunostaining. Immunoactivity was not found in the epithelial cells of carcinoma in situ components occasionally seen in the specimens, but stromal macrophage-like cells which had invaded such lesions were positive. In most specimens a subpopulation of tissue neutrophils was also positive. Normally appearing epithelium in all specimens investigated was negative, and no other tissue elements were stained in any of the samples. Ten samples of normal female breast tissue were negative. This is the first report on the immunohistochemical distribution of uPAR in human cancer tissue, and the results provide evidence for a role of the urokinase receptor in providing tissue macrophages a means of directing proteolysis at sites of breast cancer invasion. This macrophage-mediated proteolytic activity is suggested to be involved in the invasion and subsequent distant spreading of this malignancy.

Growth inhibition in response to estrogen withdrawal and tamoxifen therapy of human breast cancer xenografts evaluated by in vivo 31P magnetic resonance spectroscopy, creatine kinase activity, and apoptotic index.

Estrogen withdrawal versus tamoxifen (TAM) treatment was compared in two human breast cancer xenografts, the estrogen-dependent ZR75-1 and its estrogen-independent subline ZR75/LCC-3. The following parameters were determined: tumor growth, NTP:P(i) by 31P magnetic resonance spectroscopy, apoptotic index, and creatine kinase (CK) activity. Tumors of each line were grown in ovariectomized nude mice during stimulation from a s.c. 17 beta-estradiol pellet. At a tumor size of approximately 350 mm3, the pellet was removed from one-half of the animals. The remaining one-half served as controls. In parallel experiments, injections of TAM were initiated instead of estrogen withdrawal. Estrogen withdrawal as well as TAM induced growth inhibition of ZR75-1 tumors, whereas ZR75/LCC-3 was resistant to both types of therapy. Growth inhibition of ZR75-1 by estrogen withdrawal, but not by TAM, was accompanied by an 80% increase of the NTP:P(i) ratio (P < 0.01) and a significantly decreased cytosolic CK activity (P < 0.01). No significant change in pH was observed. These changes seemed not to be related to changes in apoptotic index. None of the described changes occurred in ZR75/LCC-3. The present data indicate: (a) ZR75-1 and ZR75/LCC-3 xenografts respond differently to estrogen withdrawal and TAM with regard to growth inhibition, 31P magnetic resonance spectroscopy, and CK activity; (b) estrogen withdrawal, but not TAM, induced a decrease in the CK activity of estrogen-dependent tumor tissue, and (c) increased apoptosis did not explain the growth inhibition and the increase in NTP:P(i) induced by estrogen withdrawal. The results indicate other growth inhibitory mechanisms of TAM in addition to competitive inhibition of the estrogen receptor.

Effect on growth and cell cycle kinetics of estradiol and tamoxifen on MCF-7 human breast cancer cells grown in vitro and in nude mice.

The effects of estradiol and tamoxifen (TAM) on the estrogen-dependent human breast cancer cell line MCF-7 grown in vitro and in nude mice were compared. The effect on growth was determined by cell number in vitro and by tumor growth curves in nude mice. The effects on the cell cycle kinetics were determined by repeated flow cytometric DNA analyses in vitro and in vivo and by the technique of labeled mitosis in nude mouse-grown tumors. Under in vitro conditions, estradiol induced a pronounced increase in S-phase fraction and cell number. TAM inhibited growth of MCF-7 cells with a concomitant increase in the G1 phase from 60% to 75%. In nude mice, MCF-7 only formed tumors in estradiol-supplemented mice. No differences were observed in growth and cell kinetics between 0.1 and 1.0 mg of estradiol. Daily i.p. injections of TAM resulted in tumor growth inhibition with shrinkage of tumors. The flow cytometric DNA analysis and percentage of labeled mitosis investigations revealed no significant differences in the proliferation kinetics of TAM-treated and control tumors. Calculating the cell loss factor demonstrated an increase from 69% in control tumors to 107% in TAM-treated tumors. These experiments have shown that the cell kinetic effect of TAM is different when MCF-7 cells are grown in vitro versus in vivo. In contrast to the in vitro data, the in vivo data indicate that the growth-inhibitory effect of TAM is not mediated through a perturbation of the cell cycle.