scholarly journals Evaluation of Isolation Methods for Circulating Tumor Cells (CTCs)

2016 ◽  
Vol 40 (3-4) ◽  
pp. 411-419 ◽  
Author(s):  
Galatea Kallergi ◽  
Eleni Politaki ◽  
Saad Alkahtani ◽  
Christos Stournaras ◽  
Vassilis Georgoulias
Keyword(s):  
Recovery Rate ◽  
Low Frequency ◽  
Immunomagnetic Separation ◽  
Breast Cancer Cell Lines ◽  
Poor Prognostic Factor ◽  
Cell Search ◽  
Isolation Methods ◽  
Cancer Types ◽  
Gradient Separation ◽  
Density Gradient Separation

Background: Detection of CTCs is a poor prognostic factor for many cancer types; however, their very low frequency represents an obstacle for their detection. The objective of the current study was to compare the performance of commonly used methods for CTCs isolation. Methods: The evaluated methods using spiking experiments of MCF7, SKBR3 and MDA MB-231 breast cancer cell lines were (i) ficoll density gradient separation (DGS), (ii) red blood cell lysis (Erythrolysis) isolation, (iii) positive immunomagnetic selection (EpCAM Dynal beads), (iv) two different negative immunomagnetic separation systems (Dynal vs Miltenyi CD45 beads) as well as (v) the Cell Search platform and (vi) the ISET system. Results: The recovery rates of Erythrolysis and DGS were 39% and 24%, respectively. Magnetic isolations are ranked from the worse to the best recovery rate as follows:, Myltenyi-anti-CD45 microbeads (24%); Dynal-anti-EpCAM beads (75%); Dynabeads-anti-CD45 (97%). CTCs isolation from blood samples using the CellSearch and ISET systems revealed that the recovery rate for Cell Search and ISET was 52% and 95%, respectively. Conclusions: Dynal-anti-CD45 beads have the best recovery rate compared to other magnetic methods. Furthermore the recovery rate of ISET was higher compared to Cell Search, especially for the more aggressive MDA-MB 231 cell line.

scholarly journals Down-Regulation of the Proteoglycan Decorin Fills in the Tumor-Promoting Phenotype of Ionizing Radiation-Induced Senescent Human Breast Stromal Fibroblasts

Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1987
Author(s):  
Eleni Mavrogonatou ◽  
Adamantia Papadopoulou ◽  
Asimina Fotopoulou ◽  
Stathis Tsimelis ◽  
Heba Bassiony ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Ionizing Radiation ◽  
Cancer Progression ◽  
Breast Cancer Cell Lines ◽  
Phenotypic Trait ◽  
Mrna Levels ◽  
Human Breast ◽  
Down Regulation ◽  
Stromal Fibroblasts ◽  
Poor Prognostic Factor

Down-regulation of the small leucine-rich proteoglycan decorin in the stroma is considered a poor prognostic factor for breast cancer progression. Ionizing radiation, an established treatment for breast cancer, provokes the premature senescence of the adjacent to the tumor stromal fibroblasts. Here, we showed that senescent human breast stromal fibroblasts are characterized by the down-regulation of decorin at the mRNA and protein level, as well as by its decreased deposition in the pericellular extracellular matrix in vitro. Senescence-associated decorin down-regulation is a long-lasting process rather than an immediate response to γ-irradiation. Growth factors were demonstrated to participate in an autocrine manner in decorin down-regulation, with bFGF and VEGF being the critical mediators of the phenomenon. Autophagy inhibition by chloroquine reduced decorin mRNA levels, while autophagy activation using the mTOR inhibitor rapamycin enhanced decorin transcription. Interestingly, the secretome from a series of both untreated and irradiated human breast cancer cell lines with different molecular profiles inhibited decorin expression in young and senescent stromal fibroblasts, which was annulled by SU5402, a bFGF and VEGF inhibitor. The novel phenotypic trait of senescent human breast stromal fibroblasts revealed here is added to their already described cancer-promoting role via the formation of a tumor-permissive environment.

A modified method for labeling human platelets with indium-111 oxine using albumin density-gradient separation.

Radiology ◽  
1982 ◽  
Vol 145 (1) ◽  
pp. 219-221 ◽  
Author(s):  
R W Bunting ◽  
R J Callahan ◽  
S Finkelstein ◽  
R S Lees ◽  
H W Strauss
Keyword(s):  
Density Gradient ◽  
Human Platelets ◽  
Modified Method ◽  
Indium 111 ◽  
Gradient Separation ◽  
Density Gradient Separation

Correlation of NFE2L2 mutation with higher tumor mutation burden (TMB), microsatellite instability (MSI) and PD-L1 expression in 3,716 cases of Chinese pan-cancer.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e16211-e16211
Author(s):  
Bin Wu ◽  
Aijun Li ◽  
Keji Chen ◽  
Lin Chen ◽  
Qin Zhang ◽  
...  
Keyword(s):  
Leucine Zipper ◽  
Statistical Correlation ◽  
Related Factor ◽  
Chi Square ◽  
Basic Leucine Zipper ◽  
Poor Prognostic Factor ◽  
Cancer Types ◽  
The Difference ◽  
Chi Square Analysis ◽  
Pan Cancer

e16211 Background: Nuclear factor E2-related factor-2 (NFE2L2) gene encodes a transcription factor which is a member of basic leucine zipper (bZIP) proteins family. Overexpression of NFE2L2 lead to cell proliferation and promoted tumor metastasis. Previous report indicated that NFE2L2 mutation (NFE2L2-MT) was an independent poor prognostic factor in esophageal squamous cell carcinoma (ESCC). However, the correlation between NFE2L2 mutation and pan-cancer types of TMB, MSI, and PD-L1 expression is unclear. Methods: TMB analysis was performed in 3,716 Chinese pan-cancer patients who underwent NGS sequencing using a 539 gene panel. The TMB calculation included synonymous and nonsynonymous mutations and InDels. MSI analysis was performed in 3,110 patients. MSI-H was defined as above 10% positive of the 195 tested microsatellites sites. The PD-L1 expression analysis was performed in 3,415 patients with immunohistochemistry staining (IHC) by antibody SP263. PD-L1 positive was defined as greater than or equal to 1%. The statistical correlation was investigated using Chi-square analysis. TMB value was compared using Wilcoxon Rank Sum test. We used TCGA public database to verify the result. Results: The mutation frequency of NFE2L2 mutation was 2.66% (99/3716). The TOP 5 cancer types were liver cancer 3.53% (14/397), lung cancer 2.97% (42/1416), colorectal cancer 2.02% (7/347), gastric cancer 1.36% (3/221), soft tissue sarcoma 0.53% (1/189). NFE2L2-MT had a significant correlation with higher TMB (p = 2.2e-16), compared with NFE2L2 wild-type (NFE2L2-WT). Among 3110 samples with MSI status, the MSI-H percentage of NFE2L2-MT and NFE2L2-WT were 8.60% (8/93) and 1.33% (40/3017), respectively (p = 1.29e-7). In 3,415 patients with PD-L1 protein expression information, the PD-L1 positive percentage of NFE2L2-MT and NFE2L2-WT were 51.52% (51/99) and 61.9% (1,268/2,048), respectively. NFE2L2-WT has higher PD-L1 positive percentage than NFE2L2-MT (p = 0.01). NFE2L2-MT was significantly correlated with higher TMB and MSI when we used TCGA data to verify, p<0.0001. However, the survival analysis of 1661 MSKCC immunotherapy cohort showed that the median OS of NFE2L2-MT vs NFE2L2-WT was 21 months vs 18 months (p=0.858), but the difference was not significant. Conclusions: NFE2L2 mutation has a very significant correlation with higher TMB and MSI, but not related to PD-L1 expression. However, whether NFE2L2-MT is related to the efficacy of immunotherapy was still unclear and more clinical data were needed.

The photosynthetic carbon metabolism of Zea mays and Gomphrena globosa: the location of the CO2 fixation and the carboxyl transfer reactions

1970 ◽  
Vol 48 (4) ◽  
pp. 777-786 ◽  
Author(s):  
J. A. Berry ◽  
W. J. S. Downton ◽  
E. B. Tregunna
Keyword(s):  
Zea Mays ◽  
Bundle Sheath ◽  
Oxidative Decarboxylation ◽  
Gomphrena Globosa ◽  
Phosphorylated Compounds ◽  
Bundle Sheath Cells ◽  
Phosphoglyceric Acid ◽  
Photosynthetic Carbon Metabolism ◽  
Gradient Separation ◽  
Density Gradient Separation

Zea mays and Gomphrena globosa form labeled aspartate and malate (C4-acids) via β-carboxylation of P-enolpyruvate during photosynthesis. Studies of the redistribution of 14C in pulse- and chase-type feedings of 14CO2 indicate that most labeled phosphorylated compounds are formed from the C4-acids. A mechanism involving CO2 as a transitory intermediate is advanced to explain the carboxyl transfer from the C4-acids to 3-phosphoglyceric acid (3-PGA). In this model, CO2 is generated through the oxidative decarboxylation of malic acid by "malic" enzyme, and is refixed by RuDP carboxylase to form 3-PGA. The pattern of labeling of photosynthetic products, the extractable enzyme activities, and the gas exchange properties of these plants appear to be consistent with this proposed sequence of reactions. The location of 14C-labeled compounds was determined by radioautography, and by nonaqueous density gradient separation. Differential grinding was used to study the location of some photosynthetic enzymes. These indicate that CO2 fixation by β-carboxylation occurs in the leaf mesophyll. The carboxyl transfer and the reactions leading to the photosynthesis of starch appear to be confined predominantly to the bundle sheath cells. Rapid transport of C4-acids from the site of CO2 fixation in the mesophyll to the bundle sheath may occur by plasmodesmata.

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