The dichloromethane extract of the flowers of Helianthus angustifolius L. (Asteraceae, Heliantheae) was investigated in vitro for its cytotoxic activity using human cancer cell lines: CCRF-CEM leukemia, MDA-MB-231 breast cancer, U251 glioblastoma, HCT 116 colon cancer cells, and the human lung fibroblast cell line MRC-5. Cytotoxicity-guided fractionation led to the isolation of four related hel...

Malignant cells have enhanced sensitivity to inhibition of growth by thymidine. Cell growth of the permanent lymphoid cell line CCRF-CEM, originating from a patient with acute lymphoblastic leukemia, is inhibited by 3 x 10(-5) M thymidine, compared to 1 to 5 x 10(-3) M thymidine required to inhibit growth of normal lymphoid lines. Thymidine-resistant cells were isolated at a frequency of approx...

Today, quantitative real-time PCR is the method of choice for rapid and reliable quantification of mRNA transcription. However, for an exact comparison of mRNA transcription in different samples or tissues it is crucial to choose the appropriate reference gene. Recently glyceraldehyde 3-phosphate dehydrogenase and beta-actin have been used for that purpose. However, it has been reported that th...

abstract background: high temperatures have destructive effects on cancer cells by damaging proteins and structures within cells. gold nanoparticles (aunps) can act as drug delivery vehicles, especially for cancer therapy. due to the selective intake of asparagine molecules into malignant cells, aunps were coated with asparagine; and ccrf-cem human t-cell leukemia cells were treated with the ne...

Tumor cell-derived exosomes are considered a potential source of cancer biomarkers. Here, we developed an electrochemical sensing platform for the rapid and simple detection exosomes, using CCRF-CEM exosome as model. The utilizes cyclic nicking enzyme cleavage hybridization chain reaction (HCR) dual-signal amplification. A hairpin aptamer probe (HAP) containing was designed assay. specific bind...

This study reports the isolation and characterization of a variant of the human CCRF-CEM leukemia cell line that overproduces the carrier protein responsible for the uptake of reduced folates and the folate analogue methotrexate. The variant was obtained by adapting CCRF-CEM cells for prolonged times to stepwise decreasing concentrations of 5-formyltetrahydrofolate as the sole folate source in ...

A numerical model was used to investigate the effect of acetylene concentration in feed gas on molecular growth and solid particle nucleation argon-acetylene CCRF discharges. Results showed that for large conversion yields small concentrations discharge, ionization kinetic is driven by Penning process governed neutral polyynes. The cluster size distribution predicted shows unlikely this situati...

Six novel antifolates with 2,4-diaminopyrimidine-fused five-membered rings containing either pyrrole or cyclopentene rings were characterized at the cellular and biochemical level. Five of these antifolates were more growth inhibitory to the CCRF-CEM human leukemia cell line than methotrexate [MTX; drug concentration effective at inhibiting cell growth by 50% relative to untreated control (EC50...

Lymphoblasts obtained directly from the peripheral blood buffy coat of a child with acute lymphoblastic leukemia partially or completely repopulated the depleted bone marrow spaces of 2 hamsters i.v. infused shortly after whole body irradiation in the supralethal dose range. A more extensive series of experiments with lymphoblasts (CCRF-CEM) isolated directly in continuous suspension cultures f...