title: Isolation and partial identification of eight endogenous G1 inhibitors of JB-1 ascites tumor cell proliferation.
abstract: Eight endogenous G1 inhibitors of the proliferation of JB-1 ascites tumor cells have been isolated and characterized. The activity of the inhibitors has been analyzed on synchronized JB-1 (murine plasmacytoma) and L1A2 (murine sarcoma) cells in vitro using flow cytometry. The purified inhibitors have been tested for in vivo activity on partially synchronized JB-1 and L1A2 ascites tumors in situ. Four of the inhibitors exhibited a high degree of cell specificity (chalone-like inhibitors) and were chemically related, whereas the other four showed no cell specificity. In most extractions, the amount of cell-specific activity is more than 50% of the total G1-inhibitory activity. Most of the inhibitors are low-molecular-weight peptides and glycopeptides.
mesh_terms: D000818:Animals; D002852:Chromatography, Ion Exchange; D004353:Drug Evaluation, Preclinical; D005434:Flow Cytometry; D007399:Interphase; D007700:Kinetics; D051379:Mice; D009374:Neoplasms, Experimental / Q000503:physiopathology; D010455:Peptides / Q000302:isolation & purification* / Q000502:physiology; D010954:Plasmacytoma / Q000503:physiopathology*; D012513:Sarcoma, Experimental / Q000503:physiopathology*
chemical_list: D010455:Peptides