Camptothecin analogs with enhanced activity against human breast cancer cells. II. Impact of the tumor pH gradient

@article{Adams2005CamptothecinAW,
  title={Camptothecin analogs with enhanced activity against human breast cancer cells. II. Impact of the tumor pH gradient},
  author={David J Adams and Miriam L. Wahl and James L. Flowers and Banalata Sen and Michael O Colvin and Mark W. Dewhirst and Govindarajan Manikumar and Mansukh C. Wani},
  journal={Cancer Chemotherapy and Pharmacology},
  year={2005},
  volume={57},
  pages={145-154}
}
Human breast tumors often exist in an acidic and hypoxic microenvironment, which can promote resistance to radiation and chemotherapies. A tumor-selective pH gradient arises in these tumors which favors uptake and retention of drugs like camptothecin that are weak acids. We evaluated the effect of alkyl substitutions at the 7 position in seven CPTs with varying groups at the 10 position on modulation by acidic extracellular pH in three human breast cancer cell lines. Growth inhibition was… 

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