Differential changes in purine nucleotides after Doxorubicin treatment of human cancer cells in vitro

The present investigation was performed to elucidate the role of purine nucleotides as potential indicators of chemosensitivity of malignant tumors. Drug-sensitive (s) and -resistant (r) tumor cell lines grown as monolayers (s: T47D, MCF-7 wild-type; r: NCI/ADR-RES, MCF-7/MDR) or as multicellular spheroids (T47D; NCI/ADR-RES) were exposed to 0.1, 1.0, and 10.0 microM Doxorubicin for up to 24 h. Purine nucleotides were assayed using HPLC and with some selected spheroids using imaging bioluminescence. The data show that in the time frame of the experiments reproducible and statistically significant changes in the nucleotides only occur at the highest drug concentration investigated. Under these conditions and using monolayer cultures, Doxorubicin caused a significant increase in ATP and GTP in sensitive but not in resistant cancer cells. Consequently, this differential change may be exploited for drug sensitivity testing in vitro. Doxorubicin exposure to spheroids was associated with significant increases in ATP and GTP in both sensitive and resistant variants. However, the kinetic of the changes in GTP was largely different between T47D and NCI/ADR-RES spheroids with a long-lasting, almost 3-fold elevation and a smaller, relatively short transient increase in GTP, respectively. Supplementing experiments with Doxorubicin treatment under inhibition of oxidative phosphorylation with Oligomycin abolished the drug-induced ATP and GTP peaks at persistent increases in ADP and AMP. Assuming that the spheroids may represent the in vivo situation to a better degree than monolayer cultures, experimental in vivo studies should clarify whether kinetic changes in GTP could be used as differential markers for the chemosensitivity of solid tumors. The experiments using Oligomycin support the hypothesis that purine nucleotides may be recycled from DNA fragments that result from the interaction of the drug with the DNA strands.     

Metabolic markers of breast cancer: enhanced choline metabolism and reduced choline-ether-phospholipid synthesis

Specific genetic alterations during malignant transformation may induce the synthesis and breakdown of choline phospholipids, mediating transduction of mitogenic signals. The high level of water-soluble choline metabolites in cancerous breast tumors, relative to benign lesions and normal breast tissue, has been used as a diagnostic marker of malignancy. To unravel the biochemical pathways underlying this phenomenon, we used tracer kinetics and 13C and 31P magnetic resonance spectroscopy to compare choline transport, routing, and metabolism to phospholipids in primary cultures of human mammary epithelial cells and in MCF7 human breast cancer cells. The rate of choline transport under physiological choline concentrations was 2-fold higher in the cancer cells. The phosphorylation of choline to phosphocholine and oxidation of choline to betaine yielded 10-fold higher levels of these metabolites in the cancer cells. However, additional incorporation of choline to phosphatidylcholine was similar in both cell types. Thus, enhanced choline transport and augmented synthesis of phosphocholine and betaine are dominant pathways responsible for the elevated presence of choline metabolites in cancerous breast tumors. Uniquely, reduced levels and synthesis of a choline-ether-phospholipid may also serve as a metabolic marker of breast cancer.     

Obstetricians' opinions regarding patient choice in cesarean delivery

OBJECTIVE: To survey the opinions of Israeli obstetricians regarding their position on patient choice cesarean delivery. METHODS: Short anonymous questionnaires were sent by mail. The questionnaire included basic demographic data followed by three short case presentations of patients requesting cesarean delivery without a medical indication; the respondents were asked if they would consent to the patients' request. Respondents were then asked about their personal preferences on the mode of delivery, their attitude towards women's right to choose cesarean delivery, and whether obstetricians should inform their patients of this right. RESULTS: Of the 650 questionnaires sent, 257 were returned. Most of the respondents were specialists, aged 35 years or older, and worked in hospitals. Seventy-five percent were male, and 27% had a teaching academic degree. The consent rate for patient choice cesarean delivery in the three case presentations ranged from 40% to 79%. Only 9% of the respondents said they would prefer cesarean delivery for themselves (if female) or for their partners. Forty-five percent supported women's right to choose cesarean delivery, and half of them stated that obstetricians should inform their patients of this right. CONCLUSION: Although the vast majority (91%) of the Israeli respondents personally prefer vaginal delivery, almost half of them support women's autonomy to choose cesarean delivery. Consequently, approximately 50% of the respondents were willing to perform cesarean delivery on request because of their support of women's autonomy, despite the fact that they believe that vaginal delivery is a better option.     

Association between standard clinical and pathologic characteristics and the 21-gene recurrence score in breast cancer patients: a population-based study

BACKGROUND: The 21-gene recurrence score (RS) assay has been reported to accurately predict the risk of disease recurrence and chemotherapy benefit in women with estrogen receptor (ER)-positive, lymph node (LN)-negative breast cancer who are treated with tamoxifen. To the authors' knowledge, the association between the RS and clinicopathologic characteristics has been studied in randomized and case-control trials, but not in the general population. METHODS: The authors analyzed the correlation between clinicopathologic breast cancer characteristics and RS among 300 consecutive Israeli patients who were referred to undergo the test between October 2004 and October 2006. RESULTS: Low, intermediate, and high RS were noted in 109 patients (36%), 134 patients (45%), and 57 patients (19%), respectively. The median age of the patients was 54 years and the median tumor size was 1.6 cm. High tumor grade, low progesterone receptor expression, infiltrating ductal histology, and high HER-2 expression were found to be associated with a high RS, whereas patient age, tumor size, ER expression, and lymph node micrometastasis were found to correlate poorly with the RS. The ability of any of these variables, either alone or in combination, to predict the RS was limited. Similarly, neither commonly used guidelines nor the Adjuvant! Online software were found to be able to predict the RS. CONCLUSIONS: The results of the current study suggest that neither standard clinicopathologic features nor commonly used assessment tools can reliably predict the RS among referred breast cancer patients compared with a clinical trial population. These data also may indicate the need for additional studies regarding the role of the RS among certain subsets of breast cancer patients, including those with noninfiltrating ductal carcinoma histology and the presence of lymph node micrometastasis.     

Effect of combining electrocardiographic interpretation results on diagnostic accuracy

In order to test the diagnostic performance of various ECG computer programs a reference library of ECGs is being established and evaluation methods are being developed in an international co-operative project. A pilot study was undertaken in which 250 validated electrocardiograms (ECG) and vectorcardiograms (VCG) comprising seven diagnostic groups i.e., normal, left, right and bi-ventricular hypertrophy, anterior, inferior and combined infarction have been analysed independently by 11 different computer programs as well as by six cardiologists. A coding scheme was applied to assign individual diagnostic statements to a common set and to obtain combined program and cardiologist interpretation results. Preliminary results indicate that the accuracy of classification by different programs varies widely. Total accuracy varied between 57.2% and 75.8% (median 69.4%). The cardiologists had a higher accuracy (median 74.3%) than the majority of programs, at least when using the standard ECG. As it is considered premature to stress individual program results, in view of the current sample size, the enhancement in diagnostic accuracy obtained by combining interpretation results is highlighted. Indeed combined cardiologist and program results demonstrated the highest accuracy i.e., respectively 78.7% and 76.1%, higher than the result of any individual reader or program. The combined result of the five most accurate programs was 78.4%, that of the six least accurate was 71.5%, which is again higher than the respective individual components. These findings demonstrate that the combination of expert knowledge of computer programs can, similar to panel review and group analysis in clinical practice, enhance diagnostic accuracy.     

Placental abruption occurring soon after labor combined spinal-epidural analgesia

We present a case of placental abruption necessitating emergency cesarean section in an otherwise uncomplicated patient soon after initiation of combined spinal-epidural analgesia in labor. Administration of spinal opioids has the potential to cause fetal bradycardia due to uterine hypertonicity following rapid onset of analgesia. In this case, a previously bloody show before placement of combined spinal-epidural analgesia may have been evidence of a small abruption. We hypothesize that uterine hypertonicity following administration of spinal opioids may have hastened the development of an existing placental abruption.     

T-cell phenotypic profiles in the cerebrospinal fluid and peripheral blood of multiple sclerosis patients.

Thirty-nine patients with clinically definite multiple sclerosis (MS) entered the study. Of 28 subjects with a relapsing-remitting course, 19 were classified in acute relapse, 9 in remission; 11 patients had a progressive course without remissions. Furthermore, 6 subjects with inflammatory neurological disease (IND), and 10 with non-inflammatory and non-neoplastic neurological disease (NIND) were investigated. We simultaneously studied cerebrospinal fluid (CSF) and peripheral blood (PB) T-, B- and NK-cell subsets, as defined by following monoclonal antibodies: anti-CD3, -CD4, -CD8, -CD19, -CD16, -HLA-DR and -IL-2-R. We found a significant increase of CD4+ T-cells compared with controls in CSF, with respect to PB, of MS patients, particularly in acute relapse. An increase of HLA-DR+ cell percentages in the CSF than in the PB in all MS groups, especially in attacks of MS but also in remission, was also observed, with a positive correlation between CD4+ T-cell and DR+ cell percentages both in the CSF as well as in the PB of relapsing MS patients. These findings, together with the increase of IL-2-R+ cells in the PB, particularly in relapsing MS, give further support for the presence of a systemic T-cell activation in MS.     

Isometric exercise test for predicting gestational hypertension

One hundred normotensive young primigravidas underwent an isometric handgrip exercise test between 28 and 32 weeks of gestation. The same individual performed the tests and the results were withheld from the physician taking care of the patient. The study demonstrates a sensitivity of 81% and a specificity of 96.5%. These results demonstrate a reliable predictive ability of this simple exercise test for gestational hypertension.     

Studies of the metabolism of human breast cancer spheroids by NMR

Spheroids present a model for tumor behavior in vivo. In NMR studies, a problem of spheroid adhesion occurs. Here, we present a method which overcomes this problem and show the variations in phosphate metabolite concentrations as well as the rate of glucose metabolism as a function of spheroid age.