title: Cell cycle phases of two human lung tumor cell lines derived from squamous cell carcinoma and pulmonary metastasis of a rhabdomyosarcoma (HS 24 and HS 57) and N-acetylalanine aminopeptidase activity.
abstract: The cell cycle phase distribution of two human lung cancer cell lines (HS 24 and HS 57) grown both to half-confluency and confluency was determined. Both cell lines were then synchronized by applying a thymidine block forcing them to stay in the S-phase. After removal of the thymidine block, which allows the cells to go then through their cell cycle phases, N-acylamino acylpeptide hydrolase (EC 3.4.19.1) activity was measured using N-acetylalanine-p-nitroanilide as substrate (N-acetylalanine aminopeptidase). At the same times that the enzymatic activity was measured, the cell cycle phase distribution was analyzed, in order to determine the cell cycle phase of N-acetylalanine aminopeptidase synthesis. However, the cell cycle phase of N-acetylalanine aminopeptidase synthesis could not be determined. This result was caused by the fact that the cells remained synchronous only for a short period of time.
authors.affiliation: Krankenhaus Rohrbach, Heidelberg, West Germany.
authors.forename: O L
authors.initials: OL
authors.lastname: Schoenberger
authors.forename: S
authors.initials: S
authors.lastname: Beikirch
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000201:enzymology / Q000473:pathology*; D002453:Cell Cycle; D004790:Enzyme Induction; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology / Q000473:pathology* / Q000556:secondary; D009363:Neoplasm Proteins / Q000032:analysis*; D010447:Peptide Hydrolases / Q000032:analysis*; D012208:Rhabdomyosarcoma / Q000201:enzymology / Q000473:pathology / Q000556:secondary*; D014407:Tumor Cells, Cultured / Q000201:enzymology / Q000473:pathology*
chemical_list: D009363:Neoplasm Proteins; D010447:Peptide Hydrolases; C038220:acylaminoacyl-peptidase