In vitro detection of circulating tumor cells compared by the CytoTrack and CellSearch methods.

Comparison of two methods to detect circulating tumor cells (CTC) CytoTrack and CellSearch through recovery of MCF-7 breast cancer cells, spiked into blood collected from healthy donors. Spiking of a fixed number of EpCAM and pan-cytokeratin positive MCF-7 cells into 7.5 mL donor blood was performed by FACSAria flow sorting. The samples were shipped to either CytoTrack or CellSearch research facilities within 48 h, where evaluation of MCF-7 recovery was performed. CytoTrack and CellSearch analyses were performed simultaneously. Recoveries of MCF-7 single cells, cells in clusters, and clusters were determined. The average numbers of MCF-7 cells/cells in clusters/clusters recovered from blood by the CytoTrack and CellSearch methods were 103 ± 5.9/27 ± 7.9/11 ± 3.5 (95 % CI) and 107 ± 4.4/20 ± 7.1/10 ± 3.5, respectively, with no difference between the two methods (p = 0.37/p = 0.23/p = 0.09). Overall, the recovery of CytoTrack and CellSearch was 68.8 ± 3.9 %/71.1 ± 2.9 %, respectively (p = 0.58). In spite of different methodologies, CytoTrack and CellSearch found similar number of CTCs, when spiking was performed with the EpCAM and pan cytokeratin-positive cell line MCF-7. The results suggest that CytoTrack and CellSearch have similar abilities to identify CTC in vitro.

New Approach for Interpreting Changes in Circulating Tumour Cells (CTC) for Evaluation of Treatment Effect in Metastatic Breast Cancer.

AIM: Attempts have been made to use CTC values for interpretation of treatment response and to guide change of chemotherapy by using a static cut-off of 5 CTC to stratify patients in favourable or unfavourable responders. We propose a new approach to interpret treatment effect using significant changes in CTC values (SCV-limits(1)) as grouping parameter for responders and non-responders to chemotherapy among metastatic breast cancer (mBC) patients. METHOD: CTC were analysed using the CellSearch System in blood from 47 mBC patients before the start of new chemotherapy and before the third cycle of therapy. The new and old approach to interpret changes in CTC values were compared in relation to progression free survival (PFS). RESULTS: The new approach using significant CTC change (P = .032) and the old approach using static cut-off (P > .001) correlated significantly with PFS using a cohort of 47 patients. CONCLUSION: We propose a new approach to interpret significant changes between baseline and follow-up CTC values as a tool for assessing treatment effect in mBC. Our approach stratified patients in new risk groups that were stratified significantly with respect to PFS. More patients are needed to balance the size of the risk groups for better comparison to the existing approach based on a 5 CTC cut-off.

The load of short telomeres, estimated by a new method, Universal STELA, correlates with number of senescent cells.

Short telomeres are thought to trigger senescence, most likely through a single - or a group of few - critically shortened telomeres. Such short telomeres are thought to result from a combination of gradual linear shortening resulting from the end replication problem, reflecting the division history of the cell, superimposed by a more stochastic mechanism, suddenly causing a significant shortening of a single telomere. Previously, studies that have tried to explore the role of critically shortened telomeres have been hampered by methodological problems. With the method presented here, Universal STELA, we have a tool that can directly investigate the relationship between senescence and the load of short telomeres. The method is a variant of the chromosome-specific STELA method but has the advantage that it can demonstrate short telomeres regardless of chromosome. With Universal STELA, we find a strong correlation between the load of short telomeres and cellular senescence. Further we show that the load of short telomeres is higher in senescent cells compared to proliferating cells at the same passage, offering an explanation of premature cell senescence. This new method, Universal STELA, offers some advantages compared to existing methods and can be used to explore many of the unanswered questions in telomere biology including the role that telomeres play in cancer and aging.

[Effect of healthy school meal on selection of blood parameters]. / Effekten af sund skolekost på udvalgte blodparametre.

INTRODUCTION: It was tested if a healthy school meal would result in significant changes in selected blood parameters and if such parameters would lie within generally accepted optimal values. MATERIAL AND METHODS: The study was a block-randomized, controlled trial in which 145 pupils delivered blood before (week 39) and after the intervention (week 49). The intervention group received a healthy meal for two months (25-30% of the daily intake of calories). Blood samples were analyzed for 17 parameters related to carbohydrate, fat and protein metabolism as well as vitamins and minerals. RESULTS: During the intervention period, the intervention group showed a significant change in mean values for thyroid-stimulating hormone (TSH), calcium (CA) haemoglobin (HB), cobalamin (COBA) and creatinine (CREA) compared with the control group (p < 0.025). The optimal value for vitamin D in serum is about 80 nmol/l. In week 49, more than 94% of the pupils were lower than 80 nmol/l, and they generally had low calcium values. CONCLUSION: The intervention group showed significant alterations in TSH, CA, HB, COBA and CREA values from the start to the end of the intervention period compared with the control group. The results should be confirmed in a study with more participants over a longer period of time. The teenagers in the study did not have sufficient vitamin D. Treating adolescents with a daily dose of vitamin D should be considered .

[Vitamin D deficiency]. / Vitamin D-mangel.

The importance of vitamin D for osteoporosis and fractures has been known for more than 40 years. Vitamin D deficiency is diagnosed by measuring 25-hydroxyvitamin D (25-OHD), which should be > 50 nmol/l year round. Recent research suggests that a number of severe diseases could be prevented by increasing 25-OHD to 80 nmol/l. Despite a strong focus on such increase, recommendations for intake of Vitamin D have not been changed and the present recommendations are too low even to ensure > 50 nmol/l. To achieve optimal concentrations > 80 nmol/l, we estimate that 50-70 microgram of vitamin D per day for everyone from the age of 10 years is necessary. Until the safety of this dose has been further documented, we recommend 35-38 micrograms/day.