Colony formation

N-ras, H-ras, K-ras Signal transduction pathway Inhibition of cell proliferation and colony formation change in morphology, enhanced melanin synthesis decrease of in vivo tumorigenicity... 

RET Receptor tyrosine kinase Inhibition of colony formation... 

Pleiotrophin Growth factor Inhibition of colony formation decrease of in vivo tumor growth, tumor angiogenesis, and metastatic ability... 

Human papilloma virus (HPV) Cervical cancer, oral cancer E6, E7 Inhibition of cell proliferation and colony formation... 

Altered cell morphology Increased growth rate Increased saturation density Formation of multilayers Reduced adhesion to substratum Colony formation in soft agar Reduced serum requirement Altered growth factor requirement Tumor formation in athymic nude mice... 

Sporicidal activity can be determined against spores in liquid suspension or against spores dried on carriers. In principle, techniques are similar to those described for bactericidal tests. However, it should be realized that spores must germinate and outgrow before colony formation is observed. For this reason, incubation of recovery media should be continued for several days. 

Broxmeyer HE, Sherry B, Lu L, et al. Myelopoietic enhancing effects of murine macrophage inflammatory proteins 1 and 2 on colony formation in vitro by murine and human bone marrow granulocyte/macrophage progenitor cells. J Exp Med... 

As the first step, the toxicity of PFOA and PFNA was assessed using the colony formation assay (Fig. 6) cells at the density of 250 cells/plate were seeded in... 

Fig. 6 BALB/c 3T3 cell transformation assay Colony formation assay...

The effects of Li+ upon hematopoiesis have been proposed to be due to two different systems modification of the activity of the membrane Na+/K+-ATPase, and the inhibition of adenylate cyclase. Monovalent cation flux, in particular Na+ transport, is known to influence the differentiation and proliferation of hematopoietic stem cells. For instance, ouabain, an effective inhibitor of the membrane Na+/K+-ATPase, blocks the proliferation of lymphocytes and has been shown to attenuate the Li+-induced proliferation of granulocyte precursors [208]. Conversely, Li+ can reverse the actions of amphotericin and monensin, which mediate Na+ transport and which inhibit CFU-GM, CFU-E, and CFU-MK colony formation in the absence of Li+ [209]. Therefore, the influence of Li+ upon normal physiological cation transport—for example, its influence upon Na+/K+-ATPase activity—may be partly responsible for the observed interference in hematopoiesis. 

Arlett, C.E, Smith, D.M., Clark, G.M., Green, J.H.L., Cole, J., McGregor, D.B. and Asquith, J.C. (1989). Mammalian cell assays based upon colony formation. In UKEMS Subcommittee on Guidelines for Mutagenicity Testing. Report Part III Statistical Evaluation of Mutagenicity Test Data, (Kirkland, D.J., Ed.). Cambridge University Press, pp. 66-101. 

Other cytokines synthesised by activated neutrophils (but not bloodstream neutrophils) include interferon-a G-CSF and M-CSF. Interferon-a expression is stimulated by exposure of blood neutrophils to G-CSF (incubation times >3 h are required), but expression of this cytokine is not activated by exposure to either LPS or fMet-Leu-Phe. G-CSF induces 0.95- and 1.2-kb mRNA molecules, the latter transcript containing the message plus a 3 noncoding region. Synthesis of interferon-a protein (as determined by a radioimmunoassay) requires incubation times in excess of 6 h, and the functions of this cytokine include inhibition of neutrophil-colony formation and platelet formation in vitro. 

A final interesting aspect of the growth phenotype of the H801 strain is that it is much slower in forming colonies on agar plates, especially when hydrogen serves as the electron donor for sulfate reduction. Assuming that colony formation involves reduction of the redox potential of the environ-... 

To investigate the cloning efficiency of the progenitor cells in these cocultures we analyzed their colony formation ability in methylcellulose supplemented with recombinant growth factors. The results indicate that within the first two weeks mb SCF as well as SI SCF or S1+MS5 stroma induced... 

H. Wu, U. Klingmuller, A. Acurio, J. G. Hsiao, and H. F. Lodish, Functional interaction of erythropoietin and stem cell factor receptors is essential for erythroid colony formation,... 

McCulloch, E.A., Siminovitch, L., and Till, J.E. (1964) Spleen-colony formation in anemic mice... 

Wiktor-JedrzeJczak, W., Szczylik, C., Gornas, P., Sharkis, S.J., Ahmed, A. (1979) Different Marrow Cell Nnmbers Requirements for the Haematopoietic Colony Formation and the Cure of the W/W Anemia. Experientia 35, 546-547. 

Granting that precise mechanisms responsible for the characteristic anticancer activity and mammalian toxicity of vinblastine, vincristine, and related compounds have not been rigorously established, it nevertheless is important to describe representative biological and biochemical actions of the drugs that may have mechanistic pertinence. The susceptibility to mitotic spindle dissolution of cell lines with 100-fold differences in sensitivity to vinblastine has been investigated 14). There was an excellent correlation between drug concentrations required to produce inhibition of cell colony formation and those required to dissolve mitotic spindles. It is noteworthy that effects on the mitotic spindle of vinblastine occur very rapidly and can be detected within 30 sec. 

Moved] Cranberry fruit of Early Black cultivar was fractionated chromatographically and fractions were analyzed for flavonoid content. The effects of the flavonoid fractions and ursolic acid, an abundant triterpenoid in cranberry peel, were assessed in two models of colon cancer and one model of breast cancer. Clonogenic soft agar assays were used to determine the effect of these compounds on tumor colony formation in HCT-116, HT-29 and MCF-7 cells. MTT and trypan blue assays were performed to assess their ability to inhibit tumor cell proliferation. TUNEL assays were performed to assess apop-totic response to the cranberry compounds. The proanthocyanidins inhibited tumor colony formation in HCT-116 and HT-29 cells in a dose-dependent manner, with greater effect on the HCT-116 cell line. Ursolic acid strongly inhibited tumor colony formation in both colon cell lines. These compounds also decreased proliferation in all three tumor cell lines with the HCT-116 cell line most strongly affected. (150 words)... 

Liberty, A. M. Hart, P. E. Neto, G. G. Ursolic Acid and Proanthocyanidins from Cranberry (Vaccinium macrocarpon) Inhibit Colony Formation and Proliferation in HCT-116 and HT-29 Colon and MCF-7 Breast Tumor Cells. Proceedings of the 233rd American Chemical Society National Meeting, Chicago, IL, March 25-29, 2007. 

The synthetic lethal effect between PARP inhibition and BRCAl/2 deficiency was first described in 2005 by Farmer et al and Bryant et al in preclinical studies (17, 18). BRCAl/2 deficient cell lines are more sensitive to PARP inhibition than BRCAl/2 proficient cell lines in colony formation assays and in xenograft models (17, 18). BER and HR are DNA repair pathways that carry out the repair of SSB and DSB, respectively. Inhibition of either pathway alone is not lethal, but loss of both pathways causes cell death (Fig. 2). Mechanistically, PARP inhibition blocks the activity of BER and leads to DNA SSB accumulation inside cells. When cells enter the next round of DNA replication, these DNA SSBs are converted to DNA DSBs which can be efficiently repaired through... 

Figure 3. Summary of the selection procedure for cutinase-defective mutant. The T-8 strain of F. solani was mutagenized by ultraviolet irradiation, grown for 3 days, and plated on medium containing 0.5% acetate and agarose for 5-7 days to permit colony formation. Subsequently, the colonies were overlaid with an agarose solution containing 1.26 mM PNB. The parental colonies hydrolyzed the substrate and turned yellow while the presumptive mutant colonies remained white and were selected for analysis. Further details are given in Ref. 13.

HV163 Jeong H. ]., Y. Lam, and B. O. de Lumen. Barley lunasin suppresses ras-induced colony formation and inhibits core histone acetylation in mammalian cells. J Agric Food Chem 2002 50(21) 5903-5908. 

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