Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.1.21 (thymidine kinase)
 7,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

With L-15 as the base medium, drug-resistant variants were isolated from two amphibian tissue culture strains: the Xenopus laevis A8 diploid cell line and the ICR 2A cell line of Rana pipiens. Four different classes of variants were obtained: (1) A8 cells resistant to chloramphenicol, an inhibitor of mitochondrial protein synthesis; (2) A8 cells resistant to ouabain, an inhibitor of the Na+/K+-activated ATPase of the plasma membrane;(3) ICR 2A cells resistant to low (20 microgram/ml) and high (300 microgram/ml) levels of bromodeoxyuridine (BUdR), a thymidine analog which interferes with the pyrimidine salvage pathway; and (4) ICR 2A cells resistant to 2,6-diaminopurine (DAP), an adenine analog which interferes with the purine salvage pathway. Unlike the other variants, isolation of BUdR resistant cells is a 2-step process. Resistance to low levels of BUdR is phenotypically expressed by a reduction in thymidine transport activities while resistance to high levels of this compound is evidenced by greatly reduced levels of thymidine kinase activity. DAP-resistant cells, which are characterized by reduced levels of adenine phosphoribosyl transferase (APRT) activity, do not die in AAT (adenine, aminopterin, thymidine) selection medium. This suggests that these cells utilize adenine efficiently. With MEM as the base medium, an asparagine independent clone was isolated from the ICR 2A cell line. When compared with the wild type, this variant exhibited a slightly reduced growth rate in the presence or absence of asparagine.
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PMID:Amphibian cells in culture. II. Isolation of drug-resistant variants and an asparagine-independent variant. 30 57

To explore the diagnostic value, pre-operative serum thymidine kinase 1(TK1), CEA, CA 19-9 and CA 72-4 levels were measured in 106 patients with colorectal carcinoma (53 colon and 53 rectal carcinoma patients) and 53 healthy controls. Sandwich Elisa, biotin-labeled antibody kit was used for TK1, and other tumor markers were measured using electro-chemiluminescence. Serum TK1 levels were significantly higher in CRC than in healthy controls (p <0.05) and showed significant associations with tumor stage, histopathological grade, lymph node status and metastasis (p <0.01). TK1 showed the highest (0.824-0.862) area under receiver operating characteristics curve (AUC) in comparison to other markers, and the AUC of the panel of combination tests performed even better (0.935-0.952). Significant variation was observed between the single biomarker test and their combination (Z test, p <0.01) and the Hosmer-Lemeshow test showed an adequate model of calibration. The algorithm based on combination of TK1, CEA, CA19-9 and CA72-4 can improve the diagnostic efficiency in CRC patients.<br />.
Asian Pac J Cancer Prev 2020 Nov 01
PMID:Clinical Significance and Role of TK1, CEA, CA 19-9 and CA 72-4 levels in Diagnosis of Colorectal Cancers. 3324 67