A small molecule that can block autophagy - a mechanism that allows cells in our body handle cellular waste and release building blocks for recycling - in cancer cells has been discovered in a new study.
The molecule called microRNA-101 was found to particularly increase the sensitivity of breast cancer cells towards one of the most commonly used treatments for breast cancer.
It is found naturally in human cells.
Many cancer cells increase autophagy, literally means "self-eating," and the increased release of building blocks equip the cancer cells with a growth advantage and can render them resistant towards treatment.
"We have discovered a small molecule that can block autophagy in different cancer cells and specifically, this molecule can increase the sensitivity of breast cancer cells towards one of the most commonly used treatments for breast cancer," said Professor Anders H. Lund, at BRIC, University of Copenhagen.
Lead researcher Lisa Frankel continued, "We have shown that microRNA-101 can turn off specific genes and thereby inhibit autophagy in cancer cells.
"The fact that microRNA molecules can regulate autophagy is quite new and our results disclose a large and interesting field within cancer research," he added
MicroRNA-101 is often lost in liver cancer, prostate cancer and breast cancer.
By controlling the level of microRNA-101 in cells of different cancer types, the researchers from BRIC found that microRNA-101 regulates autophagy.
In addition, the researchers found that breast cancer cells become more sensitive towards treatment with the anti-hormone Tamoxifen, when they via microRNA-101 turn off the autophagy system.
The results have just been published in EMBO Journal.