A common diabetes drug – metformin - and another drug used to treat a group of inherited and acquired disorders may have a role in fighting against resistant breast cancers that currently have no targeted therapy, suggests a study. The study, led by the University of Chicago, revealed that the two existing drugs, named metformin and haemin, suppress tumor growth in mice.

Marsha Rosner, Professor at the varsity, said that this is the first joint use of these two drugs. They seem to have decoded a new mechanism and found ways to use it.

Investigators noted that the primary anti-cancer target for haemin is a transcription factor BACH1 (BTB and CNC homology1). This protein is highly expressed in triple negative breast cancers and has a role in metastasis. BACH1 targets mitochondrial metabolism and inhibits a vital source of cellular energy. When BACH1 is high, the energy source is shut down. However, when cancer cells were treated with haemin, BACH1 was reduced, thereby making BACH1-depleted cancer cells change metabolic pathways. This caused cancers vulnerable to metformin to suppress mitochondrial respiration. This novel combination of haemin plus metformin was thus found to suppress tumor growth, and this was confirmed in mouse tumor models.

These findings can extend beyond breast cancer. BACH1 expression is enriched not only in triple negative breast cancers, but is also evident in many other cancers including lung, kidney, uterus, prostate and acute myeloid leukemia. (IANS)