These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Potent cytotoxic action of the immunotoxin SWA11-ricin A chain against human small cell lung cancer cell lines.
    Author: Derbyshire EJ, Henry RV, Stahel RA, Wawrzynczak EJ.
    Journal: Br J Cancer; 1992 Sep; 66(3):444-51. PubMed ID: 1325825.
    Abstract:
    The cytotoxic activity profile of an immunotoxin, SWA11-ricin A chain, recognising a cell-surface antigen associated with human small cell lung cancer (SCLC), was examined in detail using a panel of SCLC, non-SCLC and non lung tumour cell lines in tissue culture. SWA11-ricin A chain was potently and selectively active against three SCLC cell lines of both classic and variant morphologies, inhibiting the incorporation of 3H-leucine with an IC50 of 5 x 10(-11) M. At a concentration of 1 x 10(-8) M, the SWA11 immunotoxin could selectively eliminate in excess of 99.9% of clonogenic tumour cells. Intoxication proceeded rapidly following a 4 h lag phase; the initial rate of protein synthesis inhibition occurred with a t50 of 2 h and a t10 of 7 h. The cytotoxic activity of SWA11-ricin A chain was potentiated by 100-fold in the presence of the carboxylic ionophore monensin at 1 x 10(-7) M. Kinetic studies revealed that monensin enhanced the rate of protein synthesis inhibition by two-fold and eliminated the lag phase suggesting a rapid effect on either the rate or route of internalisation. Studies with SWA11 could detect no influence of monensin on the rate of antibody internalisation and a transient delay in the delivery of internalised antibody to lysosomes was observed by immunoelectron microscopy.
    [Abstract] [Full Text] [Related] [New Search]