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Published on: January 18, 2017
Phenformin as prophylaxis and therapy in breast cancer xenografts
M V C L Appleyard1, K E Murray, P J Coates
1Centre for Oncology and Molecular Medicine, University of Dundee, Dundee DD1 9SY, UK. m.v.c.l.appleyard@dundee.ac.uk
Background:
Observations that diabetics treated with biguanide drugs have a reduced risk of developing cancer have prompted an enthusiasm for these agents as anti-cancer therapies. We sought to determine the efficacy of the biguanide phenformin in the chemoprophylaxis and in the treatment of oestrogen receptor (ER)-positive MCF7 and receptor triple-negative MDAMB231 xenografts in immunocompromised mice. We also compared the efficacy of phenformin and metformin in the treatment of MDAMB231.
Methods:
Immunocompromised mice were divided into groups: (1) phenformin administered for 2 weeks prior to cell injection; (2) established tumours treated with phenformin; (3) established tumours treated with metformin (only for MDAMB231 tumours); (4) untreated controls. Post-treatment tumours, liver and spleen were harvested for further analysis.
Results:
Phenformin significantly inhibited both the development and growth of MCF7 and MDAMB231 tumours, and for MDAMB231 at greater efficacy than metformin without murine toxicity. The number of mitotic figures was significantly fewer in xenografts treated with phenformin compared with controls. Results suggested that the mechanism of action of phenformin in vivo is consistent with AMPK activation.
Conclusion:
Phenformin has clinical potential as an antineoplastic agent and should be considered for clinical trials both in ER-positive and triple-negative breast cancer.
Insights
Biguanide drug phenformin shows promise in reducing cancer risk. Studies indicate phenformin effectively inhibits breast cancer tumor development and growth in mice, suggesting potential as an anti-cancer therapy.
Area of Science:
- Oncology
- Pharmacology
Background:
- Biguanide drugs, like phenformin, are being investigated for anti-cancer properties due to observed reduced cancer risk in diabetic patients.
- Estrogen receptor (ER)-positive (MCF7) and triple-negative (MDAMB231) breast cancer models were utilized.
Purpose of the Study:
- To evaluate phenformin's efficacy in preventing and treating ER-positive and triple-negative breast cancer xenografts.
- To compare phenformin and metformin in treating MDAMB231 tumors.
Main Methods:
- Immunocompromised mice received phenformin pre-injection or post-tumor establishment.
- Established MDAMB231 tumors were treated with either phenformin or metformin.
- Control groups received no treatment.
Main Results:
- Phenformin significantly inhibited the development and growth of both MCF7 and MDAMB231 tumors.
- Phenformin demonstrated greater efficacy than metformin in treating MDAMB231 tumors without causing toxicity.
- Reduced mitotic figures in phenformin-treated xenografts suggest a mechanism involving AMPK activation.
Conclusions:
- Phenformin exhibits significant anti-cancer effects in preclinical models.
- Phenformin warrants consideration for clinical trials in both ER-positive and triple-negative breast cancer.
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