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

Search MEDLINE/PubMed


  • Title: Potentiation of cytotoxicity by 3-aminobenzamide in DNA repair-deficient human tumor cell lines following exposure to methylating agents or anti-neoplastic drugs.
    Author: Babich MA, Day RS.
    Journal: Carcinogenesis; 1988 Apr; 9(4):541-6. PubMed ID: 3356063.
    Abstract:
    We studied the potentiation by 3-aminobenzamide (3AB) of killing of nine human cell lines exposed to alkylating agents. Cell lines included normal, transformed and DNA repair-proficient and -deficient phenotypes. 3AB potentiated cell killing by the methylating agents methylmethanesulfonate (MMS) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in all lines tested. The degree of potentiation ranged from 1.7- to 3.8-fold, based on the LD99. The average potentiation observed with MMS (2.7-fold) was greater than with MNNG (2.2-fold). On average the potentiation of MMS and MNNG killing of repair-deficient Mer- lines (2.4-fold) was similar to that of repair-proficient Mer+ lines. The degree of 3AB potentiation of MNNG killing (2.0-fold) was similar in Mer+ Rem- lines and in Mer+ Rem+ lines. Mer+ Rem+, Mer+ Rem-, Mer- Rem+, and Mer- Rem- strains all appeared proficient in a 3AB-sensitive DNA repair pathway. Within experimental error, 20 mM 3AB did not inhibit the removal of the MNNG-induced methylpurines 7-methylguanine, O6-methylguanine and 3-methyladenine from the DNA of repair-proficient Mer+ Rem+ HT29 cells, consistent with evidence that 3AB inhibits the ligation step of excision repair. 3AB potentiated cell killing by the bifunctional alkylating agents 1-(2-chlorethyl)-1-nitrosourea or busulfan, two anti-neoplastic drugs, by only 0.9- to 1.5-fold. These drugs therefore produce DNA damage which is not efficiently repaired by the pathways that repair methylated bases.
    [Abstract] [Full Text] [Related] [New Search]