A new study showed that anthracycline proved to be very effective in survival in the case of HER2-positive breast cancer that was previously operated, but turned out to be ineffective in cases of HER2-negative tumors.
HER2-positive cancers test positive for a protein called human epidermal growth factor receptor 2 (HER2) and tend to grow quickly.
Anthracyclines are a class of chemotherapeutic agents based upon samine and tetra-hydro-naphthacene-dione, used to treat a wide range of cancers, including (but not limited to) leukemias, lymphomas, and breast, uterine, ovarian, and lung cancers.
Anthracyclines inhibit DNA and RNA synthesis by intercalating between base pairs of the DNA/RNA strand, thus preventing the replication of rapidly-growing cancer cells.
They also create iron-mediated free oxygen radicals that damage the DNA and cell membranes.
Anthracyclines are also capable if inhibiting topoisomerase II enzymes, preventing DNA from relieving torsional stress during replication.
As well as many of the expected adverse reactions of chemotherapeutic agents, anthracyclines are notorious for causing cardiotoxicity. There exists evidence that the affect of cardiotoxicity increases in long term survivors, from 2% after 2 years to 5% after 15 years.
Anthracyclines-based regimens have been long used in the vast majority of early breast cancer patients. But taking individual trials, the absolute benefit is not consistent across studies.
The most interesting is that the effect of the drug may not based just on HER2 status. Another gene called topoisomerase II alpha (or topo2) may also play a role in how well anthracyclines work.