How chemotherapy may trigger breast cancer recurrence

Credit: Unsplash+

A recent study led by Ramya Ganesan of Emory University and published in the open-access journal PLoS Biology reveals that a standard chemotherapy drug can inadvertently awaken dormant cancer cells, potentially promoting cancer growth and recurrence.

This finding has critical implications for the understanding and treatment of cancer recurrence, especially in breast cancer.

While chemotherapy has been effective in reducing mortality rates in many types of cancer, up to 23% of breast cancer patients experience a recurrence within five years.

This recurrence often results from dormant cells that become reactivated. Previous research suggested that chemotherapy might trigger this reactivation, but the mechanism remained unclear.

The researchers utilized both cell and mouse models of breast cancer for this study. In the cell model, they incorporated not only cancer cells but also non-cancer stromal cells—connective tissue cells commonly found in breast tissue.

When exposed to the chemotherapy drug docetaxel, the team discovered that even at low doses, the stromal cells were injured while the cancer cells were not. The treatment also induced a re-entry of the cancer cells into the cell cycle.

The study identifies the release of two cell-signaling molecules, granulocyte colony-stimulating factor (G-CSF) and interleukin-6 (IL-6), as the catalyst for the reawakening of dormant cells.

These molecules were released by the injured stromal cells and acted on the dormant cells to promote their growth both in vitro and in vivo.

Implications for Treatment

These findings have three major implications:

They emphasize the role of the surrounding stromal cells, in addition to the cancer cells, in determining the response to chemotherapy.

They strengthen the case for using IL-6 serum levels as a biomarker for early recurrence in breast cancer patients undergoing chemotherapy.

They introduce G-CSF and IL-6 as potential new targets for preventing recurrence.

Looking Ahead

Dr. Ganesan and Dr. Sukhatme stated, “Transient blockade of cytokine signaling during chemotherapy administration may prevent tumor recurrence.”

By identifying the role of IL-6 and G-CSF, this research presents new avenues for the development of targeted therapies that could prevent the reawakening of dormant cancer cells, thereby potentially reducing rates of cancer recurrence.


The study offers groundbreaking insights into the unintended consequences of chemotherapy in awakening dormant cancer cells, thus providing new targets and strategies for preventing cancer recurrence.

Further studies are needed to validate these findings in humans and to develop effective therapeutic interventions based on these new targets.

If you care about breast cancer, please read studies about a major cause of deadly breast cancer, and common blood pressure drugs may increase death risk in breast cancer.

For more information about cancer, please see recent studies that new cancer treatment could reawaken the immune system, and results showing vitamin D can cut cancer death risk.

The research findings can be found in PLoS Biology.

Follow us on Twitter for more articles about this topic.

Copyright © 2023 Knowridge Science Report. All rights reserved.