Scientists in Australia believe they have discovered a better way to treat the deadliest and most aggressive form of breast cancer.

Unlike chemotherapy, the new method only kills and slows the growth of cancer cells in breast tissue, not normal, healthy cells.

The oral medication also targets metastatic tumors that have spread to other parts of the body and are resistant to chemotherapy.

Triple-negative breast cancer accounts for up to 15% of all breast cancers and is known to grow and spread relatively quickly, even among young patients.

To date, there is no targeted drug treatment to combat this form of cancer, leaving patients with only a few options: intensive chemotherapy or cutting-edge immunotherapy. Even in this case, the probability of relapse within five years is high.

If the cancer spreads to distant sites beyond the localized breast tissue, the five-year survival rate can drop from 91% to 12%.

New forms of treatment are urgently needed to save lives.

"This is an exciting development in the battle against triple-negative breast cancer," said breast cancer expert Theresa Hickey of the University of Adelaide, who led trials of the new oral drug.

"The results of the current study suggest that this drug may be the key to improving survival."

The drug in question is called CDDD11-8 and was originally developed to treat acute myeloid leukemia (AML).

AML is a cancer that develops in the bone marrow and is difficult to target. Cancer cells survive, grow and spread by increasing the production of proteins, particularly in a pathway called cyclin-dependent kinase 9 (CDK9).

To date, the US Food and Drug Advisory Board has not approved any drug that inhibits CDK9, although one version has shown initial clinical benefits.

In 2022, researchers at the University of South Australia developed CDDD11-8, which selectively inhibits CDK9. When tested in animal models, the oral drug produced "a strong inhibition of tumor growth" that "translated into improved survival of animals" with leukemia.

Now the same drug promises to be used to treat triple-negative breast cancer.

A blood test that detects over 50 types of cancer

"It's still early days, but based on the initial data, we think that inhibiting this protein may lead to a cure for triple-negative breast cancer and that this new drug should be further developed," says Hickey.

She and her team at the University of Adelaide believe that targeting CDK9 may also work in other aggressive cancers that are "transcriptionally addicted".

Transcription is the copying of genetic instructions into RNA molecules, which then help control the production of proteins.

Compared to healthy cells, transcription is often "out of control" in cancer cells. This helps the disease grow and spread quickly, leading to worse patient outcomes.

Triple-negative breast cancer is characterized by a particularly high abundance of transcription factors. Accordingly, which of all scientists should try to stop?

The CDK9 pathway may be a useful target because normal, healthy cells do not rely on it as much for survival as aggressive cancer cells.

Hickey and her colleagues believe that CDDD11-8 should now be evaluated clinically in the most aggressive type of breast cancer, writes Science Alert, cited by "Objects".

In initial experiments when this new drug was applied to cell line models of triple-negative breast cancer, researchers observed a reduction in cancer growth and an increase in cancer cell death with varying degrees of success depending on the dose.

The drug also shows promise in live mouse models of breast cancer. In mice treated with the oral drug, tumors shrank and protein expression was reduced. No adverse effects on vital organs were observed.

CDDD11-8 has the potential to work in humans as well. After testing its effects on tissue obtained from a breast cancer patient and on three-dimensional organoids, the team found encouraging signs of success without toxic side effects on healthy cells.

This is likely due to the fact that healthy cells are not as dependent on CDK9 activity as some cancers, the authors explain.

"Although this drug is promising as a potential treatment for triple-negative breast cancer, it needs further development before moving to human trials," Hickey concluded.

"Hopefully that will happen within the next five years, if not sooner."

Follow the channel of

breast cancer